Effect of electrodes on the characteristics of copper-nickel alloy resistors covered with a zinc protective layer and sintered in air

Effect of electrodes on the characteristics of copper-nickel alloy resistors covered with a zinc protective layer and sintered in air | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effect of electrodes on the characteristics of copper-nickel alloy resistors covered with a zinc protective layer and sintered in air Wen Hsi Lee, Ching Feng Chien, Zihao Lin This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7872541/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study mainly aims to solve the issue of selecting suitable electrode materials for Cu–Ni alloy resistors that are sintered at high temperatures in air, enabled by a zinc protective layer covering the Cu–Ni paste to replace the reducing atmosphere. Because the electrodes connecting the Cu–Ni alloy resistors are directly exposed to high temperatures in air during sintering, three types of electrode materials were selected: thick-film printed aluminum electrodes, sputtered thin-film aluminum electrodes, and thick-film printed silver electrodes. In addition, three variations in the length of the zinc protective layer covering the Cu–Ni paste were examined—equal to, longer than, or shorter than the Cu–Ni resistive layer. For both thick-film printed aluminum electrodes and sputtered thin-film aluminum electrodes co-fired with zinc-protected Cu–Ni resistor paste at 850°C for 10 minutes, the portions of the aluminum electrodes not in contact with the Cu–Ni paste were partially oxidized, resulting in increased electrode resistance. leading to a larger temperature coefficient of resistance (TCR) for the Cu–Ni alloy chip resistor (1390 ppm/℃). When thick-film printed silver electrodes were co-fired with zinc-protected Cu–Ni resistor paste at 850°C for 10 minutes, the portions of the silver electrodes in contact with the Cu–Ni resistor paste were protected from oxidation due to the higher oxide formation enthalpy of Cu–Ni compared to silver. Because the silver electrode combined with the zinc-protected, air-sintered Cu–Ni alloy resistor exhibited extremely low electrode and contact resistances, the resulting resistor showed an excellent TCR of about 224 ppm/℃。 This study successfully fabricated zinc-protected Cu–Ni alloy resistors sinterable in air at 850°C using silver electrodes, achieving superior resistance characteristics. Furthermore, by adjusting the relative lengths of the zinc protective layer and the Cu–Ni resistive layer, the oxidation degree of the Cu–Ni resistive layer could be tuned to adjust its resistance from hundreds of micro-ohms to several ohms. Air sintering Cu-Ni alloy Termination TCR The equivalent circuit Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 1. Introduction Currently, chip resistors are still predominantly fabricated using precious-metal alloys for both the resistive body and the terminal electrodes. In passive chip resistors, silver, palladium, and ruthenium remain the mainstream materials, produced by thick-film screen printing followed by sintering in air[1]. For this reason, to avoid using precious metals, the industry has begun to adopt thick-film printed Cu–Ni base-metal pastes[2]. Yet these base-metal alloy resistor processes must undergo heat treatment in a reducing atmosphere, which is costlier and less efficient than today’s thick-film sintering processes[3]. Thus, while replacing precious-metal alloys with base-metal alloys in chip resistors can reduce material costs, it contributes little to lowering the overall device manufacturing cost. Only through innovative technology—integrating thick-film printing with Cu–Ni base-metal resistor pastes that can be sintered in air—can full base-metal implementation and a substantial reduction of chip resistor costs be achieved4]. Earlier studies employed a zinc paste as a protective layer, coating it over the surface of the Cu–Ni resistor paste[5]. In this approach, the zinc protective layer played a crucial role as the outermost protective material. Zinc was chosen because of its tendency to oxidize readily when exposed to air. The overall strategy uses zinc’s oxidizability to shield the Cu–Ni alloy from direct contact with air during sintering. The zinc oxide layer formed on the surface prevents further air penetration into the Cu–Ni alloy and protects the underlying Cu–Ni layer, thereby creating a dual protection mechanism [6]. The terminal electrode material for this air-sinterable Cu–Ni system must (i) resist oxidation during high-temperature sintering at 850 °C in air and (ii) undergo co-firing with the Cu–Ni resistor layer or zinc protective layer without severe diffusion or redox reactions caused by differences in the metals’ oxidation enthalpies—reactions that could degrade the final resistor characteristics. Materials that can meet these requirements are mainly silver electrodes or aluminum electrodes, both of which are commonly used for thick-film printed electrodes sintered in air, such as the front and back electrodes of solar cells[8]. However, in the present Cu–Ni resistor system with a zinc protective layer, aluminum has the highest oxide formation enthalpy among the five metals considered, while silver has the lowest, as shown in Table 1[9]. In addition to thick-film printed aluminum and silver electrodes, this study also introduces high-density sputtered aluminum thin-film electrodes to address the relatively low density of thick-film printed aluminum. This enables comparison of how different terminal electrode materials and processes influence the characteristics of zinc-protected Cu–Ni base-metal resistors that can be sintered in air. II Experimental Preparation of pastes for thick-film printing included zinc protective paste, aluminum and silver electrode pastes, and mixed Cu–Ni (55/45 wt%) paste. Zinc, aluminum, silver, and Cu–Ni metal powders were weighed and combined with an organic solvent at 70 wt% solids loading as a vehicle, together with a resin-containing binder, to prepare the mixtures. After pre-mixing, the pastes were subjected to centrifugation for separation and washing to remove impurities and concentrate the metal powders. The pastes were then homogenized using a three-roll mill to uniformly disperse the metal powders in the organic medium, effectively eliminating bubbles and improving the stability and dispersion quality of the pastes for subsequent thick-film printing processes. After preparing the metal pastes, the corresponding process was selected according to the required structure. For thick-film structures, the following three pastes were sequentially printed: C1 terminal electrode paste, Cu–Ni resistor paste, and zinc protective paste (Fig. 1-a). Each layer was printed through a screen mask patterned according to the design and immediately dried in an oven at 150 °C for 15 minutes to remove organic solvents and volatiles from the paste, partially harden the pattern, enhance adhesion and resolution, and prevent deformation or delamination during multilayer printing or high-temperature sintering. After completing all three layers, the samples were subjected to the sintering heat treatment. For thin-film structures, the C1 aluminum terminal electrode was first deposited using a sputtering system (Fig. 1-b). The sputtering conditions were set to a DC power of 100 W under 30 sccm argon, with the substrate heated to 100 °C during deposition to promote aluminum atom migration and alignment on the surface, improving film density and crystalline quality and thus enhancing conductivity and adhesion. After sputtering, the samples were ultrasonically cleaned with isopropanol to remove the intermediate ink layer attached to the top of the aluminum, forming the aluminum electrode structure according to the design. After forming the aluminum electrodes, the Cu–Ni resistive layer and zinc protective layer were printed and subsequently heat-treated. Once the chip resistor structures were fabricated, they underwent sintering at 850 °C for 10 minutes. The sintered samples were first electrically characterized using an impedance analyzer to measure resistance values and temperature coefficients of resistance. For cross-sectional observation, an optical microscope (OM) was used to examine the surface morphology and verify the completeness of sintering. A scanning electron microscope (SEM) provided detailed imaging of the surface and cross-sectional microstructures of the thick films after sintering. Combined with energy-dispersive X-ray spectroscopy (EDS), elemental analyses of aluminum, copper, nickel, and zinc were performed on the sintered samples to reveal the elemental distributions and to assess whether diffusion or oxidation reactions had occurred. III. Results and Discussion In this study, thick-film printed or sputtered thin-film terminal electrodes were applied to Cu–Ni resistors with a zinc protective layer, sintered at high temperature in air. The terminal electrode metals used were aluminum or silver, the resistive layer consisted of copper and nickel, and the protective layer was zinc. The enthalpies of oxide formation of these metals, from highest to lowest, are: Al (−1675.7 kJ/mol), Zn (−363.6 kJ/mol), Ni (−239.7 kJ/mol), Cu (−156.1 kJ/mol), and Ag (−31.05 kJ/mol). This means aluminum most readily forms oxides during high-temperature air sintering, whereas silver is least prone to oxidation. We investigated the microstructure, equivalent circuit, and resistive characteristics of three different terminal electrodes—thick-film printed aluminum electrodes, sputtered thin-film aluminum electrodes, and thick-film printed silver electrodes—and three zinc protective layer lengths relative to the Cu–Ni resistive layer length. 1. Thick-film printed aluminum electrodes on Cu–Ni resistors with a zinc protective layer sintered in air (1) Protective zinc layer longer than the Cu–Ni resistive layer Figures 2a and 2b show cross-sectional microstructures of (a) the aluminum electrode–Cu–Ni resistive layer–zinc protective layer, and (b) the Cu–Ni resistive layer–zinc protective layer, after thick-film printed aluminum electrodes and long zinc protective layers were co-sintered at 850 °C for 10 min in air. As seen in Fig. 2b, the upper zinc protective layer oxidized to ZnO while the lower Cu–Ni alloy layer formed as intended. However, significant diffusion of zinc into the Cu–Ni alloy resistive layer occurred. In Fig. 2a, in addition to the formation of ZnO, minor diffusion of copper and nickel into the aluminum electrode and oxidation within the aluminum were observed. Notably, at the interface between the aluminum electrode and the Cu–Ni resistive layer, no aluminum oxidation was evident—likely due to zinc diffusion into the Cu–Ni layer—affecting the contact resistance between the aluminum electrode and the Cu–Ni resistive layer. After removing the ZnO protective layer, the resistance of the aluminum electrode and the Cu–Ni resistive layer were measured separately. Subtracting these from the total measured resistance yielded the contact resistance between the aluminum electrode and the Cu–Ni resistive layer, enabling construction of the equivalent circuit of the resistor. In this structure, the total resistance was 105 mΩ, the Cu–Ni resistive layer was 35.6 mΩ, each aluminum electrode was 32 mΩ (comparable to the Cu–Ni layer), and the contact resistance between the Cu–Ni resistive layer and the aluminum electrode was 2.2 mΩ. Thus, this thick-film printed aluminum electrode structure with a long zinc protective layer in air consists mainly of the resistances of the two aluminum electrodes plus the middle Cu–Ni alloy resistive layer. Because the Cu–Ni layer is sandwiched between the upper zinc protective layer and the lower aluminum electrode—both of which have higher oxide formation enthalpies than Cu and Ni, especially aluminum—the Cu–Ni resistive layer (32 mΩ) is comparable to that obtained by nitrogen-atmosphere sintering. This indicates that in the “zinc–Cu–Ni–aluminum sandwich” structure sintered in air, the Cu–Ni layer behaves as if it were sintered in a reducing nitrogen atmosphere. On the other hand, aluminum electrodes sintered at 850 °C in air exceed aluminum’s melting point (660 °C), resulting in increased oxidation. The Al/Al₂O₃ “core–shell” oxide layer thickens, raising the aluminum electrode resistance to 35.6 mΩ—higher than the Cu–Ni resistive layer. Because the resistor has two aluminum electrodes, the temperature coefficient of resistance (TCR) is dominated by the aluminum electrodes. Given the high TCR of metallic aluminum (≈3900 ppm/°C)[10], this thick-film printed aluminum electrode structure with a long zinc protective layer shows a TCR as high as 1390 ppm/°C, far exceeding the <300 ppm/°C requirement for conventional alloy resistors. (2) Protective zinc layer equal in length to the Cu–Ni resistive layer Figures 3a and 3b show cross-sections of (a) aluminum electrode–Cu–Ni resistive layer–zinc protective layer and (b) Cu–Ni resistive layer–zinc protective layer after co-sintering with a zinc protective layer equal in length to the Cu–Ni resistive layer. As seen in Fig. 3b, the upper zinc protective layer oxidized to ZnO and the Cu–Ni alloy formed; however, zinc diffusion into the Cu–Ni resistive layer was reduced compared to Fig. 2b. Because the zinc protective layer was shortened to match the Cu–Ni layer length, its ability to protect the Cu–Ni alloy from oxidation during air sintering was slightly diminished, and the oxygen content in the Cu–Ni layer increased compared to Fig. 2b. As seen in Fig. 3a, compared to Fig. 2b, copper and nickel diffusion into the aluminum electrode decreased, but oxidation of the aluminum electrode remained severe[11]. Furthermore, at the aluminum electrode–Cu–Ni interface, the higher oxygen content—due to reduced zinc diffusion—directly affected the contact resistance. After removing ZnO, the equivalent circuit of the thick-film printed aluminum electrode with an equal-length zinc protective layer was constructed. The total resistance increased slightly to 126 mΩ; the Cu–Ni resistive layer rose to 43 mΩ (due to higher oxygen content); each aluminum electrode rose slightly to 35 mΩ; and the contact resistance increased to 6.5 mΩ because of greater aluminum electrode oxidation. Thus, shortening the zinc protective layer to match the Cu–Ni layer increased oxidation of both the aluminum electrodes and the Cu–Ni resistive layer, slightly raising all resistances. The main resistance components of this structure are: two aluminum electrodes (35 mΩ each), aluminum–Cu–Ni contact resistance (6.5 mΩ), and the Cu–Ni alloy resistive layer (43 mΩ). The TCR remains dominated by the aluminum electrodes. Because the Cu–Ni resistive layer’s resistance is slightly higher than in the long zinc protective layer structure, the TCR decreased slightly to 1222 ppm/°C, but still far exceeds the <300 ppm/°C requirement. (3) Protective zinc layer shorter than the Cu–Ni resistive layer Figures 4a and 4b show cross-sections of (a) aluminum electrode–Cu–Ni resistive layer–zinc protective layer and (b) Cu–Ni resistive layer–zinc protective layer after co-sintering with a zinc protective layer shorter than the Cu–Ni resistive layer. As seen in Fig. 4b, zinc diffusion into the Cu–Ni resistive layer was further reduced compared to Fig. 2b; however, because the zinc protective layer was shorter than the Cu–Ni layer, its ability to protect the Cu–Ni alloy from oxidation during air sintering was even weaker, and the oxygen content in the Cu–Ni layer increased compared to both the long (Fig. 2b) and equal-length (Fig. 3b) zinc protective layer cases. As seen in Fig. 4a, compared to Fig. 3b, the Cu–Ni resistive layer above the aluminum electrode was almost fully oxidized where the zinc protective layer was absent. Some copper still diffused into the aluminum electrode, and oxidation of the aluminum electrode remained severe. As with Fig. 3a, reduced zinc diffusion resulted in an oxidized aluminum–Cu–Ni interface, directly affecting contact resistance. After removing ZnO, the equivalent circuit of the thick-film printed aluminum electrode with a short zinc protective layer was constructed. The total resistance rose slightly to 134 mΩ; the Cu–Ni resistive layer increased to 44.2 mΩ; and each aluminum electrode rose slightly to 38 mΩ. Clearly, shortening the zinc protective layer below the Cu–Ni layer length slightly increased both oxidation and resistance of the aluminum electrodes and the Cu–Ni layer. Nevertheless, even though part of the Cu–Ni layer was exposed during high-temperature air sintering, the oxygen content and resistivity of the Cu–Ni resistive layer increased only slightly. This outcome is attributed to the lower aluminum electrode’s high oxide formation enthalpy, which consumed oxygen and helped protect the Cu–Ni layer from heavy oxidation during air sintering[12]. The main resistance components of this structure are: two aluminum electrodes (38 mΩ each), aluminum–Cu–Ni contact resistance (6.9 mΩ), and the Cu–Ni alloy resistive layer (44.2 mΩ). The TCR remains primarily governed by the aluminum electrodes, and is comparable to that of the equal-length zinc protective layer resistor (≈1204 ppm/°C), still far exceeding the <300 ppm/°C requirement for conventional alloy resistors. 2. Sputtered Aluminum Thin-Film Electrodes with a Zinc Protective Layer for Air-Fired Cu–Ni Resistors (1) Zinc protective layer longer than the Cu–Ni resistor layer Figures 5a and 5b show microstructural analyses of the aluminum end-electrode layer/Cu–Ni resistor layer/zinc protective layer and the Cu–Ni resistor layer/zinc protective layer of Cu–Ni resistors fabricated by air sintering at 850 °C for 10 minutes using sputtered aluminum thin-film electrodes with an extended zinc protective layer. As seen clearly in Fig. 5b, besides the upper zinc protective layer oxidizing to form ZnO and the formation of the underlying Cu–Ni alloy layer—as in the thick-film printed aluminum electrode sample of Fig. 2b—the zinc in the upper protective layer still diffuses partially into the underlying Cu–Ni alloy resistor layer. Figures 5a and 2a respectively show the cross-sections of sputtered aluminum thin-film electrodes and thick-film printed aluminum electrodes with a long zinc protective layer: a sandwich structure consisting of the upper zinc protective layer, middle Cu–Ni resistor layer, and lower aluminum end electrode. It is obvious that the sputtered aluminum thin-film electrode thickness of about 2–3 μm differs significantly from the thick-film printed aluminum electrode thickness of about 10–15 μm. It is also noteworthy that, regardless of whether sputtered thin-film or thick-film printed aluminum end electrodes are used, both show clear evidence of aluminum diffusing into the zinc protective layer. Furthermore, after co-firing at 850 °C in air with the Cu–Ni resistor layer, the sputtered aluminum thin-film electrode exhibits obvious oxidation. This affects the contact resistance between the sputtered aluminum thin-film end electrode and the Cu–Ni resistor layer. After removing the upper ZnO protective layer, the resistance of the sputtered thin-film aluminum electrode and the Cu–Ni resistor layer was measured. Subtracting the resistances of the sputtered aluminum thin-film end electrode and the Cu–Ni resistor layer from the total resistance measured across both sputtered aluminum thin-film electrodes yields the contact resistance between the sputtered thin-film end electrode and the Cu–Ni resistor layer, enabling construction of the equivalent circuit of the entire resistor. For this Cu–Ni resistor, the total resistance was 128 mΩ; the Cu–Ni resistor layer resistance was 39.2 mΩ; the resistance of both sputtered aluminum thin-film end electrodes was 37.2 mΩ, close to that of the Cu–Ni resistor layer; and the contact resistance between the Cu–Ni resistor layer and the aluminum end electrode was 6.9 mΩ. Thus, the main resistance of this structure consists of the two sputtered thin-film aluminum end electrodes, the middle Cu–Ni alloy resistor layer, and the contact resistance between them. Because the Cu–Ni alloy resistor layer is sandwiched between the upper zinc protective layer and the lower sputtered aluminum electrode layer—and the oxidation enthalpy of zinc and aluminum is higher than that of copper and nickel—the Cu–Ni alloy resistor layer retains a resistance of 39.2 mΩ comparable to Cu–Ni alloy resistors fired in nitrogen. The sputtered aluminum thin-film end electrode initially measured about 10 mΩ[13] ut after fabrication of the Cu–Ni resistor with a long zinc protective layer and air firing at 850 °C (above the aluminum melting point of 660 °C), its resistance increased to 37.2 mΩ. This is due to the increased oxidation of the sputtered aluminum thin-film electrode during high-temperature air firing, as well as the reaction and diffusion of the sputtered aluminum thin-film electrode into the zinc protective layer, which reduces the thickness of the sputtered aluminum thin-film electrode. Overall, the temperature coefficient of resistance (TCR) of this structure is mainly influenced by the two sputtered aluminum thin-film end electrodes. As a result, the TCR of this resistor structure reaches 900 ppm/°C—far exceeding the low-TCR requirement (<300 ppm/°C) typical of alloy resistors. (2) Zinc protective layer equal in length to the Cu–Ni resistor layer Figures 6a and 6b show microstructural analyses of the aluminum end-electrode layer/Cu–Ni resistor layer/zinc protective layer and the Cu–Ni resistor layer/zinc protective layer of Cu–Ni resistors fabricated by air sintering at 850 °C for 10 minutes using sputtered aluminum thin-film electrodes with a zinc protective layer of the same length as the Cu–Ni resistor layer. Compared with Fig. 5b, where the zinc protective layer is longer than the Cu–Ni resistor layer, in Fig. 6b the zinc protective layer is shortened to match the Cu–Ni resistor layer length. Therefore, the ability to protect the Cu–Ni alloy resistor layer from oxidation during sintering is slightly reduced. In addition, although the lower layer is still a sputtered aluminum thin-film end electrode, its thickness is nearly an order of magnitude less than that of thick-film printed aluminum electrodes. This means that using a lower sputtered aluminum thin-film end electrode and an upper zinc protective layer to protect the middle Cu–Ni resistor layer at 850 °C in air results in a weaker oxidation resistance. Consequently, the oxidation of the middle Cu–Ni resistor layer increases and its resistance rises. After removing the upper ZnO protective layer, the equivalent circuit of the entire resistor was constructed. For the Cu–Ni resistor fabricated by air sintering at 850 °C with sputtered aluminum thin-film electrodes and a zinc protective layer of equal length, the total resistance increased slightly to 132 mΩ; the Cu–Ni resistor layer resistance increased slightly to 50.8 mΩ. Compared with Fig. 5a, where the sputtered aluminum thin-film end electrode with a long zinc protective layer had a resistance of 37.2 mΩ, in Fig. 6a, where the zinc protective layer is of equal length, the sputtered aluminum thin-film end electrode resistance decreased slightly to 32.1 mΩ. This is mainly because shortening the zinc protective layer reduces its contact area with the sputtered aluminum thin-film end electrode; thus, during co-firing the diffusion of the sputtered aluminum thin-film end electrode into the zinc protective layer is reduced, lowering its resistance. This structure’s resistance is composed of the aluminum end electrodes (32.1 mΩ), the aluminum–Cu–Ni contact resistance (8.5 mΩ), and the middle Cu–Ni alloy resistor (50.8 mΩ). Its TCR (795 ppm/°C) is improved compared to the TCR (900 ppm/°C) of the previous long zinc protective layer sample. (3) Zinc protective layer shorter than the Cu–Ni resistor layer Figures 7a and 7b show microstructural analyses of the aluminum end-electrode layer/Cu–Ni resistor layer/zinc protective layer and the Cu–Ni resistor layer/zinc protective layer of Cu–Ni resistors fabricated by air sintering at 850 °C for 10 minutes using sputtered aluminum thin-film electrodes with a shortened zinc protective layer. As shown in Fig. 7b, the upper zinc protective layer is shorter than the Cu–Ni resistor layer, providing even poorer protection against oxidation during sintering. The combined effect of the short protective layer and the thin aluminum end electrode further weakens the oxidation protection, leading to increased oxidation of the middle Cu–Ni resistor layer and a higher resistance. According to Fig. 7a, compared with Fig. 6a (equal-length zinc protective layer), the upper Cu–Ni resistor layer of the aluminum end electrode in the short zinc protective layer sample is almost completely oxidized due to the lack of coverage. Meanwhile, the contact area between the sputtered aluminum thin-film end electrode and the short zinc protective layer decreases, reducing the diffusion of the sputtered aluminum thin-film electrode into the zinc protective layer[14]is means that after co-firing with the short zinc protective layer, the sputtered aluminum thin-film end electrode remains relatively intact, and its resistance decreases. After removing the upper ZnO protective layer, the equivalent circuit of the Cu–Ni resistor fabricated by air sintering at 850 °C with sputtered aluminum thin-film electrodes and a short zinc protective layer was constructed. The total resistance increased to 146.4 mΩ; the Cu–Ni resistor layer resistance increased to 78.4 mΩ; and the resistance of the two aluminum end electrodes decreased to 25.9 mΩ. The resistance of this structure consists of the aluminum end electrodes (25.9 mΩ), the aluminum–Cu–Ni contact resistance (8.1 mΩ), and the middle Cu–Ni alloy resistor (78.4 mΩ). Its TCR dropped to 615 ppm/°C, approaching the low-TCR characteristic (<300 ppm/°C) typical of alloy resistors. This TCR result is mainly influenced by the middle Cu–Ni resistor layer (Cu–Ni TCR: 100 ppm/°C) with its high 78.4 mΩ resistance, while the influence of the sputtered aluminum thin-film end electrode (Al TCR: 3900 ppm/°C) with its lower 25.9 mΩ resistance is relatively small. 3. Thick-Film Printed Silver Electrodes with Zinc Protective Layers for Air Firing of Cu–Ni Resistors (1) Protective Zinc Layer Longer than Cu–Ni Resistive Layer Figures 8a and 8b respectively show microstructural analyses of the silver terminal electrode layer–Cu–Ni resistive layer–zinc protective layer and of the intermediate Cu–Ni resistive layer–zinc protective layer of a thick-film printed silver electrode Cu–Ni resistor with a long zinc protective layer after air co-firing at 850 °C for 10 min. According to Figure 8b, it is evident that, in addition to the top zinc protective layer being oxidized to a ZnO layer, a Cu–Ni alloy layer forms underneath but with an oxygen content higher than that of the thick-film printed aluminum electrode Cu–Ni resistor with a zinc protective layer fired in air shown in Figure 2b. The main difference is that the enthalpy of formation of oxidation of the lower silver terminal electrode differs from that of the aluminum terminal electrode in Figure 2b: it is lower than that of copper and nickel oxides. In this zinc–Cu–Ni–silver sandwich structure under high-temperature air firing, the intermediate Cu–Ni resistive layer is sandwiched between the top zinc protective layer and the lower silver terminal electrode. In practice, only the top zinc protective layer can protect the Cu–Ni layer from oxidation during high-temperature firing. The lower silver electrode not only fails to protect the Cu–Ni layer from oxidation but, because silver has a lower enthalpy of oxide formation than Cu and Ni, the Cu–Ni resistive layer must partially oxidize to protect the silver electrode from oxidation results in a slightly higher degree of Cu–Ni oxidation after co-firing at 850 °C[15]. According to Figure 8a, in addition to ZnO formation in the protective layer, the shape of the silver terminal electrode is well retained and its oxygen content is very low, indicating that no interdiffusion occurs among the silver terminal electrode, the zinc protective layer, and the Cu–Ni resistive layer, and that the silver electrode does not oxidize. The absence of oxidation in the silver terminal electrode is reflected in the contact resistance between the silver terminal electrode and the Cu–Ni resistive layer. After removing the surface ZnO layer, the resistance of the silver terminal electrode and of the Cu–Ni resistive layer were measured. By subtracting the resistance of the silver electrodes and of the Cu–Ni resistive layer from the total resistance measured across both silver electrodes, the contact resistance between the silver terminal electrodes and the Cu–Ni resistive layer can be obtained, thus enabling construction of an equivalent circuit for the whole resistor. For this structure, the total resistance of the Cu–Ni resistor is 94 mΩ, the resistance of the Cu–Ni resistive layer is 85.05 mΩ, the two silver terminal electrodes show very low resistance at 3.47 mΩ, and the contact resistance between the Cu–Ni resistive layer and the silver terminal electrodes is only 1 mΩ. Because the Cu–Ni alloy resistive layer is sandwiched between the top zinc protective layer and the lower silver electrode to form a zinc–Cu–Ni–silver sandwich structure under high-temperature air firing, where the enthalpy of oxide formation of zinc is higher than that of Cu and Ni but that of silver is lower than that of Cu and Ni, the Cu–Ni alloy resistance of 85.05 mΩ is more than twice that of aluminum-electrode Cu–Ni alloy resistors fired in air or nitrogen (35.6 mΩ). In addition, since the 850 °C firing temperature is below the melting point of silver (961 °C), the thick-film silver electrode resistance (3.47 mΩ) is about ten times lower than that of thick-film aluminum electrodes (32 mΩ) or thin-film sputtered aluminum electrodes (25.9 mΩ). Therefore, for this structure the temperature coefficient of resistance (TCR) is mainly determined by the slightly higher oxygen content of the intermediate Cu–Ni resistive layer. Given that the TCR of Cu–Ni is about 100 ppm/°C[16], this resistor exhibits a TCR of 224 ppm/°C, which meets the requirement of low-TCR alloy resistors (< 300 ppm/°C). (2) Protective Zinc Layer Equal in Length to Cu–Ni Resistive Layer Figures 9a and 9b respectively show microstructural analyses of the silver terminal electrode layer–Cu–Ni resistive layer–zinc protective layer and of the intermediate Cu–Ni resistive layer–zinc protective layer of a thick-film printed silver electrode Cu–Ni resistor with a zinc protective layer equal in length to the Cu–Ni resistive layer after air co-firing at 850 °C for 10 min. According to Figure 9b, in addition to the top zinc protective layer being oxidized to ZnO and the formation of a Cu–Ni alloy layer underneath, the oxygen content of the Cu–Ni alloy resistive layer is more severe than in Figure 8b, especially near both electrode ends. This results mainly from the shortened zinc protective layer having the same length as the Cu–Ni resistive layer, which slightly reduces the ability to protect the Cu–Ni alloy resistive layer from oxidation during high-temperature air firing. At the same time, co-firing of the Cu–Ni resistive layer with silver electrodes having lower enthalpy of oxide formation increases the oxygen content of the Cu–Ni resistive layer. According to Figure 9a, no interdiffusion occurs among the silver electrode, the zinc protective layer, and the Cu–Ni resistive layer, and under co-firing the silver terminal electrode is protected by the higher oxide formation enthalpy of Cu–Ni. Thus, as in Figure 8b, the silver terminal electrode maintains its shape and shows no oxidation. After removing the ZnO layer, an equivalent circuit was constructed. The total resistance of the Cu–Ni resistor slightly increases to 178 mΩ, with the Cu–Ni resistive layer resistance slightly increasing to 167 mΩ, the two silver terminal electrodes still showing very low resistance at 3.42 mΩ, and the contact resistance between the Cu–Ni resistive layer and the silver terminal electrodes slightly increasing to 2.07 mΩ. This increase in contact resistance is mainly due to the slightly higher oxidation of the Cu–Ni resistive layer near the silver terminal electrodes caused by shortening the zinc protective layer. This resistor consists of the two silver terminal electrode resistances (3.42 mΩ), the silver–Cu–Ni contact resistances (2.07 mΩ), and the intermediate Cu–Ni alloy resistance (167 mΩ). Its TCR is mainly influenced by the slightly higher oxygen content of the Cu–Ni resistive layer. Given that the TCR of Cu–Ni is about 100 ppm/°C, the thick-film printed silver-electrode Cu–Ni resistor with an equal-length zinc protective layer exhibits a TCR of 266 ppm/°C, which meets the low-TCR alloy resistor specification (< 300 ppm/°C). (3) Protective Zinc Layer Shorter than Cu–Ni Resistive Layer Figures 10a and 10b respectively show microstructural analyses of the silver terminal electrode layer–Cu–Ni resistive layer–zinc protective layer and of the intermediate Cu–Ni resistive layer–zinc protective layer of a thick-film printed silver electrode Cu–Ni resistor with a short zinc protective layer after air co-firing at 850 °C for 10 min. As shown in Figure 10b, because the zinc protective layer is shorter than the Cu–Ni resistive layer, its ability to protect the Cu–Ni resistive layer from oxidation during high-temperature air firing is further diminished. The oxygen content of the Cu–Ni alloy resistive layer is significantly higher than that of the long or equal-length zinc protective layers in Figures 8b and 9b. According to Figure 10a, compared with Figure 9a, the Cu–Ni resistive layer above the silver terminal electrode is almost completely oxidized due to the lack of zinc protective layer coverage. Furthermore, because the lower silver electrode has a lower enthalpy of oxide formation than the Cu–Ni resistive layer, it further worsens the oxidation of Cu–Ni near the silver terminal electrode, especially nickel oxidation[17]. The increased oxidation of the Cu–Ni resistive layer near the silver terminal electrodes directly leads to increased contact resistance between the silver terminal electrodes and the Cu–Ni resistive layer. It is clear that for a thick-film printed silver electrode Cu–Ni resistor with a short zinc protective layer, the shortened zinc protective layer results in much greater oxidation of the Cu–Ni resistive layer. Unlike thick-film printed aluminum electrodes, where the high oxide formation enthalpy of aluminum can still protect the intermediate Cu–Ni layer even when the zinc protective layer is short, the lower silver electrode not only fails to protect the intermediate Cu–Ni layer but actually aggravates oxidation of the Cu–Ni resistive layer near the silver terminal electrode. After removing the ZnO layer, an equivalent circuit was constructed. The total resistance of the Cu–Ni resistor dramatically increases to 3 Ω. Because the Cu–Ni resistive layer is much more oxidized, especially near the two silver terminal electrodes compared to the middle Cu–Ni resistive layer, unlike the previous long and equal-length zinc protective layer cases where the Cu–Ni alloy layer could be treated as a single resistor, here the Cu–Ni resistive layer can be divided into three resistors: a slightly oxidized middle Cu–Ni resistive layer and two highly oxidized Cu–Ni resistive layers near the silver terminal electrodes. Unlike the previous equivalent circuits, which consisted of five resistors (two terminal electrode resistances, two contact resistances, and the middle Cu–Ni resistance), this structure with a short zinc protective layer consists of seven resistors: two terminal electrode resistances, two contact resistances, two highly oxidized Cu–Ni resistances near the silver electrodes, and the slightly oxidized middle Cu–Ni resistance. The resistor is composed of the two silver terminal electrode resistances (3.53 mΩ), the silver–highly oxidized Cu–Ni contact resistances (4 mΩ), the highly oxidized Cu–Ni alloy resistances (1.36 Ω), and the slightly oxidized middle Cu–Ni alloy resistance (265 mΩ). Its TCR is mainly determined by both the highly oxidized Cu–Ni alloy resistances near the two silver terminal electrodes and the slightly oxidized middle Cu–Ni alloy resistance. This structure shows a TCR of 251 ppm/°C, satisfying the low-TCR alloy resistor specification (< 300 ppm/°C). Merely changing the zinc protective layer length to be shorter than the Cu–Ni resistive layer length can raise the resistor value from several hundred milliohms to several ohms while still maintaining a low TCR, which represents a major technological breakthrough for fabricating high-resistance Cu–Ni alloy resistors with low TCR. IV. Conclusions Whether using thick-film printed aluminum electrodes or thin-film sputtered aluminum electrodes with zinc protective layers for air firing of Cu–Ni resistors, the intermediate Cu–Ni resistive layer is sandwiched between the top zinc protective layer and the lower aluminum electrode. Because the oxide formation enthalpies of zinc and aluminum are higher than those of the Cu–Ni resistive layer, the Cu–Ni alloy resistance (32 mΩ) is comparable to that of Cu–Ni alloy resistors fired in nitrogen. This shows that in this zinc protective layer–Cu–Ni resistive layer–aluminum electrode sandwich structure under high-temperature air firing, regardless of whether the zinc protective layer is longer or shorter than the intermediate Cu–Ni resistive layer, the intermediate Cu–Ni resistive layer is essentially sintered in a reducing atmosphere due to the protection of the top zinc protective layer and the aluminum electrode. On the other hand, in the zinc–Cu–Ni–aluminum sandwich structure fired in air at 850 °C, because this exceeds the melting point of aluminum (660 °C), the oxidation degree of the aluminum terminal electrode increases, and aluminum diffuses into the zinc protective layer at the interface. Both factors lead to an increase in the aluminum terminal electrode resistance comparable to that of the Cu–Ni resistive layer. The TCR of the aluminum terminal electrode (3900 ppm/°C) dominates the overall TCR, so the aluminum-electrode Cu–Ni resistor fired in air with a zinc protective layer exceeds the low-TCR specification (< 300 ppm/°C). For thick-film printed silver electrodes with zinc protective layers fired in air, when the top zinc protective layer is longer than or equal in length to the Cu–Ni resistive layer, in the zinc–Cu–Ni–silver sandwich structure under high-temperature air firing only the top zinc protective layer can protect the Cu–Ni from oxidation; the lower silver electrode not only cannot protect Cu–Ni from oxidation but, because its oxide formation enthalpy is lower than that of Cu–Ni, causes the Cu–Ni resistive layer to partially oxidize to protect the silver electrode. In addition, since the 850 °C firing temperature is below the melting point of silver (961 °C), the thick-film silver terminal electrode maintains a very low resistance of 3.47 mΩ. Thus, the TCR of the overall resistor is mainly influenced by the slightly higher oxygen content of the intermediate Cu–Ni resistive layer (100 ppm/°C). The thick-film printed silver electrode Cu–Ni resistor with a zinc protective layer fired in air can achieve a TCR of 224 ppm/°C, satisfying the low-TCR specification (< 300 ppm/°C). For thick-film printed silver electrodes with zinc protective layers fired in air, when the top zinc protective layer is shorter than the Cu–Ni resistive layer, the Cu–Ni resistive layer above the silver terminal electrode is almost completely oxidized due to lack of zinc coverage, and because the lower silver electrode has a lower oxide formation enthalpy than the intermediate Cu–Ni resistive layer, it further aggravates oxidation of Cu–Ni near the silver terminal electrode, especially nickel oxidation. This leads to a dramatic increase in total resistance to 3 Ω. This resistor is composed of the two silver terminal electrode resistances (3.53 mΩ), the silver–highly oxidized Cu–Ni contact resistances (4 mΩ), the highly oxidized Cu–Ni alloy resistances (1.36 Ω), and the slightly oxidized middle Cu–Ni alloy resistance (265 mΩ). Its TCR (251 ppm/°C) is mainly influenced by both the highly oxidized Cu–Ni alloy resistances near the two silver terminal electrodes and the slightly oxidized middle Cu–Ni alloy resistance, satisfying the low-TCR specification (< 300 ppm/°C). Merely shortening the zinc protective layer relative to the Cu–Ni resistive layer can raise the resistor value from several hundred milliohms to several ohms while still maintaining a low TCR, representing a major technological breakthrough for producing high-resistance Cu–Ni alloy resistors with low TCR. Declarations Conflict of Interest Statement The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Funding Statement The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by National Science and Technology Council [NSTC112-2221-E-006-064] Author Contribution Ching Feng Chien, . Zihao Lin and Wen Hsi Lee conceived the study. Zihao Lin developed the theoretical framework. Ching Feng Chien performed the experiments, analyzed the data, and wrote the manuscript. Wen Hsi Lee contributed to the final version of the manuscript and supervised the project. Data availability The authors confirm that the data supporting the findings of this study are available within the article. References T. Sumida, "Recent Advances in Thick-Film Resistors and Target Applications," in IEEE Power Electronics Magazine, vol. 9, no. 1, pp. 70-72, Mar. (2022). Hrovat, M., & Jan, “An Investigation of Thick Film Resistor Materials' Properties During the Firing Process” Microelectronics International, 4(3), 25-29.(1987) Wen-His Lee,” Investigation of a copper–nickel alloy resistor using co-electrodeposition”,Journal of Applied Electrochemistry 50(12), May (2020) C. R. Kuo; Tzu-Chiang Kuo Wen-Hsi Lee＂A Novel Fabricating a Thick Film Cu-Ni Alloy Resistor by Screen Printing an Al Electrode and Galvanic Replacement Reaction＂IEEE Transactions on Components, Packaging and Manufacturing Technology 11, (11), Nov. (2021) Jiri Hlina＂Study of Copper-Nickel Nanoparticle Resistive Ink Compatible with Printed Copper Films for Power Electronics Applications＂Materials. 20;14(22):7039. Nov.(2021) Ajay D. Pingale＂Recent researches on Cu-Ni alloy matrix composites through electrodeposition and powder metallurgy methods: A review＂Materialstoday Proceedings,47, (11), 3301-3308, (2021) Wen-Hsi Lee, S. W. Chang, Narendra Gharini Puteri＂Air-sintered copper-nickel resistor with aluminum layer for oxidation prevention, MRS Communications,(6]), 1301-1306, (2024) Nwaeju, C.C., et al., Structural and properties evolution of copper–nickel (Cu–Ni) alloys: a review of the effects of alloying materials. Matériaux & Techniques, 2021. 109 (2): p. 204. Ren, J., et al., Effect of Different Heat Treatment Processes on the Microstructure and Properties of Cu-15Ni-3Al Alloys. Materials, 2025. 18 (12): p. 2678. Pola, A., M. Tocci, and F.E. Goodwin, Review of microstructures and properties of zinc alloys. Metals, 2020. 10 (2): p. 253. Schaffer, G. and B. Hall, The influence of the atmosphere on the sintering of aluminum. Metallurgical and Materials Transactions A, 2002. 33 (10): p. 3279-3284. Li, D., et al., Study on ultrathin silver film transparent electrodes based on aluminum seed layers with different structures. Nanomaterials, 2022. 12 (19): p. 3540. Czerwinski, F., Aluminum alloys for electrical engineering: a review. Journal of Materials Science, 2024. 59 (32): p. 14847-14892. Yarborough, B., Temperature coefficient of resistance for current sensing. Vishay Dale., Los Angeles, CT, USA, Tech. Rep, 2020. 30405 . Banks, C.E., et al., Fundamentals of screen-printing electrochemical architectures. Screen-printing electrochemical architectures, 2016: p. 13-23. Stegmann, T., et al., Interfacial Effects of Surface Roughness and Topography on the Bond Strength of Silver-Sintered Joints on Copper Substrates. Journal of Electronic Materials, 2025. 54 (5): p. 4143-4153. Zhang, W., et al., Experimental study on the thermal volatilization and condensation of zinc at 10 Pa and 200 Pa. Journal of Materials Research and Technology, 2020. 9 (3): p. 3590-3597. Tables Table1 Compariosn of dielectric properties of multilayer PZT device cofired with inner electrode of the noble metal Ag/Pd and the base metal Cu/Al ( 40/60wt%) Table (I) Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7872541","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":538861986,"identity":"5ce0148f-e727-4fe3-b736-e312bcec6c29","order_by":0,"name":"Wen Hsi 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15:45:18","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":217595,"visible":true,"origin":"","legend":"\u003cp\u003e\u0026nbsp;a,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with a longer zinc protective layer and the thick-film printed Al electrodes sintered in air\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/dfb76ca5646e26ff4ead57f7.png"},{"id":95229119,"identity":"9d3c1849-74bc-4681-9cbd-e7b75660e752","added_by":"auto","created_at":"2025-11-05 16:34:28","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":214909,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with the same length zinc protective layer and the thick-film printed Al electrodes sintered in air\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/262b4d6a4b7aa4e5df8fac97.png"},{"id":95219435,"identity":"4146b11d-486e-494f-a7e7-0f3b78cb116b","added_by":"auto","created_at":"2025-11-05 15:45:18","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":227654,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with a shorter zinc protective layer and the thick-film printed Al electrodes sintered in air\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/da3aa87d8bead29ca63d88a6.png"},{"id":95219434,"identity":"5220c280-8fc8-44d6-9e06-e2162c61eb39","added_by":"auto","created_at":"2025-11-05 15:45:18","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":226724,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with a longer zinc protective layer and the thin-film sputtered Al electrodes sintered in air\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/6718e646a53329d557866951.png"},{"id":95219442,"identity":"bfdbaaf6-54fe-4384-88d7-8fa2fe9c0615","added_by":"auto","created_at":"2025-11-05 15:45:18","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":230646,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with the same length zinc protective layer and the thin-film sputtered Al electrodes sintered in air\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/4926545cfd4a0f614b2c42c7.png"},{"id":95228590,"identity":"2ae3ace3-e8c7-4fce-8879-99525eb552f9","added_by":"auto","created_at":"2025-11-05 16:33:57","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":221298,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with a shorter zinc protective layer and the thin-film sputtered Al electrodes sintered in air\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/ef1dd8a0a5aa7cf1755c05df.png"},{"id":95229136,"identity":"65196d37-17e5-4145-b2e3-4fa56a3cdfd2","added_by":"auto","created_at":"2025-11-05 16:34:29","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":253295,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with a longer zinc protective layer and the thick-film printed Ag electrodes sintered in air\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/3abfdf9c03f371250bc935a9.png"},{"id":95219437,"identity":"f2fd9a49-4721-42ef-b558-0d74c34a2de8","added_by":"auto","created_at":"2025-11-05 15:45:18","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":235453,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with the same length zinc protective layer and the thick-film printed Ag electrodes sintered in air\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/243076c099ef597e8a4eb44a.png"},{"id":95219444,"identity":"779480c4-5c2b-4e21-bacf-568a18ffc04b","added_by":"auto","created_at":"2025-11-05 15:45:18","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":281775,"visible":true,"origin":"","legend":"\u003cp\u003ea,-b.Microstrustrure analysis and EDS mapping on the termination and the center of Cu–Ni resistors with a shorter zinc protective layer and the thick-film printed Ag electrodes sintered in air\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/000faa8af38b8f2a613cfd96.png"},{"id":95312091,"identity":"ee8992ad-230d-4635-b287-bf270e86500f","added_by":"auto","created_at":"2025-11-06 15:46:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2625920,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7872541/v1/16d3f891-7e16-40c8-bb82-93b79ce85b0f.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect of electrodes on the characteristics of copper-nickel alloy resistors covered with a zinc protective layer and sintered in air","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eCurrently, chip resistors are still predominantly fabricated using precious-metal alloys for both the resistive body and the terminal electrodes. In passive chip resistors, silver, palladium, and ruthenium remain the mainstream materials, produced by thick-film screen printing followed by sintering in air[1]. \u0026nbsp;For this reason, to avoid using precious metals, the industry has begun to adopt thick-film printed Cu–Ni base-metal pastes[2]. Yet these base-metal alloy resistor processes must undergo heat treatment in a reducing atmosphere, which is costlier and less efficient than today’s thick-film sintering processes[3]. Thus, while replacing precious-metal alloys with base-metal alloys in chip resistors can reduce material costs, it contributes little to lowering the overall device manufacturing cost. Only through innovative technology—integrating thick-film printing with Cu–Ni base-metal resistor pastes that can be sintered in air—can full base-metal implementation and a substantial reduction of chip resistor costs be achieved4].\u003c/p\u003e\n\u003cp\u003eEarlier studies employed a zinc paste as a protective layer, coating it over the surface of the Cu–Ni resistor paste[5]. In this approach, the zinc protective layer played a crucial role as the outermost protective material. Zinc was chosen because of its tendency to oxidize readily when exposed to air. The overall strategy uses zinc’s oxidizability to shield the Cu–Ni alloy from direct contact with air during sintering. The zinc oxide layer formed on the surface prevents further air penetration into the Cu–Ni alloy and protects the underlying Cu–Ni layer, thereby creating a dual protection mechanism [6].\u003c/p\u003e\n\u003cp\u003eThe terminal electrode material for this air-sinterable Cu–Ni system must (i) resist oxidation during high-temperature sintering at 850 °C in air and (ii) undergo co-firing with the Cu–Ni resistor layer or zinc protective layer without severe diffusion or redox reactions caused by differences in the metals’ oxidation enthalpies—reactions that could degrade the final resistor characteristics. Materials that can meet these requirements are mainly silver electrodes or aluminum electrodes, both of which are commonly used for thick-film printed electrodes sintered in air, such as the front and back electrodes of solar cells[8]. However, in the present Cu–Ni resistor system with a zinc protective layer, aluminum has the highest oxide formation enthalpy among the five metals considered, while silver has the lowest, as shown in Table 1[9].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn addition to thick-film printed aluminum and silver electrodes, this study also introduces high-density sputtered aluminum thin-film electrodes to address the relatively low density of thick-film printed aluminum. This enables comparison of how different terminal electrode materials and processes influence the characteristics of zinc-protected Cu–Ni base-metal resistors that can be sintered in air.\u003c/p\u003e"},{"header":"II Experimental","content":"\u003cp\u003ePreparation of pastes for thick-film printing included zinc protective paste, aluminum and silver electrode pastes, and mixed Cu–Ni (55/45 wt%) paste. Zinc, aluminum, silver, and Cu–Ni metal powders were weighed and combined with an organic solvent at 70 wt% solids loading as a vehicle, together with a resin-containing binder, to prepare the mixtures. After pre-mixing, the pastes were subjected to centrifugation for separation and washing to remove impurities and concentrate the metal powders. The pastes were then homogenized using a three-roll mill to uniformly disperse the metal powders in the organic medium, effectively eliminating bubbles and improving the stability and dispersion quality of the pastes for subsequent thick-film printing processes.\u003c/p\u003e\n\u003cp\u003eAfter preparing the metal pastes, the corresponding process was selected according to the required structure. For thick-film structures, the following three pastes were sequentially printed: C1 terminal electrode paste, Cu–Ni resistor paste, and zinc protective paste (Fig. 1-a). Each layer was printed through a screen mask patterned according to the design and immediately dried in an oven at 150 °C for 15 minutes to remove organic solvents and volatiles from the paste, partially harden the pattern, enhance adhesion and resolution, and prevent deformation or delamination during multilayer printing or high-temperature sintering. After completing all three layers, the samples were subjected to the sintering heat treatment.\u003c/p\u003e\n\u003cp\u003eFor thin-film structures, the C1 aluminum terminal electrode was first deposited using a sputtering system (Fig. 1-b). The sputtering conditions were set to a DC power of 100 W under 30 sccm argon, with the substrate heated to 100 °C during deposition to promote aluminum atom migration and alignment on the surface, improving film density and crystalline quality and thus enhancing conductivity and adhesion. After sputtering, the samples were ultrasonically cleaned with isopropanol to remove the intermediate ink layer attached to the top of the aluminum, forming the aluminum electrode structure according to the design. After forming the aluminum electrodes, the Cu–Ni resistive layer and zinc protective layer were printed and subsequently heat-treated.\u003c/p\u003e\n\u003cp\u003eOnce the chip resistor structures were fabricated, they underwent sintering at 850 °C for 10 minutes. The sintered samples were first electrically characterized using an impedance analyzer to measure resistance values and temperature coefficients of resistance. For cross-sectional observation, an optical microscope (OM) was used to examine the surface morphology and verify the completeness of sintering. A scanning electron microscope (SEM) provided detailed imaging of the surface and cross-sectional microstructures of the thick films after sintering. Combined with energy-dispersive X-ray spectroscopy (EDS), elemental analyses of aluminum, copper, nickel, and zinc were performed on the sintered samples to reveal the elemental distributions and to assess whether diffusion or oxidation reactions had occurred.\u003c/p\u003e"},{"header":"III. Results and Discussion","content":"\u003cp\u003eIn this study, thick-film printed or sputtered thin-film terminal electrodes were applied to Cu–Ni resistors with a zinc protective layer, sintered at high temperature in air. The terminal electrode metals used were aluminum or silver, the resistive layer consisted of copper and nickel, and the protective layer was zinc. The enthalpies of oxide formation of these metals, from highest to lowest, are: Al (−1675.7 kJ/mol), Zn (−363.6 kJ/mol), Ni (−239.7 kJ/mol), Cu (−156.1 kJ/mol), and Ag (−31.05 kJ/mol). This means aluminum most readily forms oxides during high-temperature air sintering, whereas silver is least prone to oxidation.\u003c/p\u003e\n\u003cp\u003eWe investigated the microstructure, equivalent circuit, and resistive characteristics of three different terminal electrodes—thick-film printed aluminum electrodes, sputtered thin-film aluminum electrodes, and thick-film printed silver electrodes—and three zinc protective layer lengths relative to the Cu–Ni resistive layer length.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e1. Thick-film printed aluminum electrodes on Cu–Ni resistors with a zinc protective layer sintered in air\u003c/u\u003e\u003c/p\u003e\n\u003cp\u003e(1) Protective zinc layer longer than the Cu–Ni resistive layer\u003c/p\u003e\n\u003cp\u003eFigures 2a and 2b show cross-sectional microstructures of (a) the aluminum electrode–Cu–Ni resistive layer–zinc protective layer, and (b) the Cu–Ni resistive layer–zinc protective layer, after thick-film printed aluminum electrodes and long zinc protective layers were co-sintered at 850 °C for 10 min in air.\u003c/p\u003e\n\u003cp\u003eAs seen in Fig. 2b, the upper zinc protective layer oxidized to ZnO while the lower Cu–Ni alloy layer formed as intended. However, significant diffusion of zinc into the Cu–Ni alloy resistive layer occurred. In Fig. 2a, in addition to the formation of ZnO, minor diffusion of copper and nickel into the aluminum electrode and oxidation within the aluminum were observed. Notably, at the interface between the aluminum electrode and the Cu–Ni resistive layer, no aluminum oxidation was evident—likely due to zinc diffusion into the Cu–Ni layer—affecting the contact resistance between the aluminum electrode and the Cu–Ni resistive layer.\u003c/p\u003e\n\u003cp\u003eAfter removing the ZnO protective layer, the resistance of the aluminum electrode and the Cu–Ni resistive layer were measured separately. Subtracting these from the total measured resistance yielded the contact resistance between the aluminum electrode and the Cu–Ni resistive layer, enabling construction of the equivalent circuit of the resistor. In this structure, the total resistance was 105 mΩ, the Cu–Ni resistive layer was 35.6 mΩ, each aluminum electrode was 32 mΩ (comparable to the Cu–Ni layer), and the contact resistance between the Cu–Ni resistive layer and the aluminum electrode was 2.2 mΩ.\u003c/p\u003e\n\u003cp\u003eThus, this thick-film printed aluminum electrode structure with a long zinc protective layer in air consists mainly of the resistances of the two aluminum electrodes plus the middle Cu–Ni alloy resistive layer. Because the Cu–Ni layer is sandwiched between the upper zinc protective layer and the lower aluminum electrode—both of which have higher oxide formation enthalpies than Cu and Ni, especially aluminum—the Cu–Ni resistive layer (32 mΩ) is comparable to that obtained by nitrogen-atmosphere sintering. This indicates that in the “zinc–Cu–Ni–aluminum sandwich” structure sintered in air, the Cu–Ni layer behaves as if it were sintered in a reducing nitrogen atmosphere.\u003c/p\u003e\n\u003cp\u003eOn the other hand, aluminum electrodes sintered at 850 °C in air exceed aluminum’s melting point (660 °C), resulting in increased oxidation. The Al/Al₂O₃ “core–shell” oxide layer thickens, raising the aluminum electrode resistance to 35.6 mΩ—higher than the Cu–Ni resistive layer. Because the resistor has two aluminum electrodes, the temperature coefficient of resistance (TCR) is dominated by the aluminum electrodes. Given the high TCR of metallic aluminum (≈3900 ppm/°C)[10], this thick-film printed aluminum electrode structure with a long zinc protective layer shows a TCR as high as 1390 ppm/°C, far exceeding the \u0026lt;300 ppm/°C requirement for conventional alloy resistors.\u003c/p\u003e\n\u003cp\u003e(2) Protective zinc layer equal in length to the Cu–Ni resistive layer\u003c/p\u003e\n\u003cp\u003eFigures 3a and 3b show cross-sections of (a) aluminum electrode–Cu–Ni resistive layer–zinc protective layer and (b) Cu–Ni resistive layer–zinc protective layer after co-sintering with a zinc protective layer equal in length to the Cu–Ni resistive layer.\u003c/p\u003e\n\u003cp\u003eAs seen in Fig. 3b, the upper zinc protective layer oxidized to ZnO and the Cu–Ni alloy formed; however, zinc diffusion into the Cu–Ni resistive layer was reduced compared to Fig. 2b. Because the zinc protective layer was shortened to match the Cu–Ni layer length, its ability to protect the Cu–Ni alloy from oxidation during air sintering was slightly diminished, and the oxygen content in the Cu–Ni layer increased compared to Fig. 2b.\u003c/p\u003e\n\u003cp\u003eAs seen in Fig. 3a, compared to Fig. 2b, copper and nickel diffusion into the aluminum electrode decreased, but oxidation of the aluminum electrode remained severe[11]. Furthermore, at the aluminum electrode–Cu–Ni interface, the higher oxygen content—due to reduced zinc diffusion—directly affected the contact resistance.\u003c/p\u003e\n\u003cp\u003eAfter removing ZnO, the equivalent circuit of the thick-film printed aluminum electrode with an equal-length zinc protective layer was constructed. The total resistance increased slightly to 126 mΩ; the Cu–Ni resistive layer rose to 43 mΩ (due to higher oxygen content); each aluminum electrode rose slightly to 35 mΩ; and the contact resistance increased to 6.5 mΩ because of greater aluminum electrode oxidation.\u003c/p\u003e\n\u003cp\u003eThus, shortening the zinc protective layer to match the Cu–Ni layer increased oxidation of both the aluminum electrodes and the Cu–Ni resistive layer, slightly raising all resistances. The main resistance components of this structure are: two aluminum electrodes (35 mΩ each), aluminum–Cu–Ni contact resistance (6.5 mΩ), and the Cu–Ni alloy resistive layer (43 mΩ). The TCR remains dominated by the aluminum electrodes. Because the Cu–Ni resistive layer’s resistance is slightly higher than in the long zinc protective layer structure, the TCR decreased slightly to 1222 ppm/°C, but still far exceeds the \u0026lt;300 ppm/°C requirement.\u003c/p\u003e\n\u003cp\u003e(3) Protective zinc layer shorter than the Cu–Ni resistive layer\u003c/p\u003e\n\u003cp\u003eFigures 4a and 4b show cross-sections of (a) aluminum electrode–Cu–Ni resistive layer–zinc protective layer and (b) Cu–Ni resistive layer–zinc protective layer after co-sintering with a zinc protective layer shorter than the Cu–Ni resistive layer.\u003c/p\u003e\n\u003cp\u003eAs seen in Fig. 4b, zinc diffusion into the Cu–Ni resistive layer was further reduced compared to Fig. 2b; however, because the zinc protective layer was shorter than the Cu–Ni layer, its ability to protect the Cu–Ni alloy from oxidation during air sintering was even weaker, and the oxygen content in the Cu–Ni layer increased compared to both the long (Fig. 2b) and equal-length (Fig. 3b) zinc protective layer cases.\u003c/p\u003e\n\u003cp\u003eAs seen in Fig. 4a, compared to Fig. 3b, the Cu–Ni resistive layer above the aluminum electrode was almost fully oxidized where the zinc protective layer was absent. Some copper still diffused into the aluminum electrode, and oxidation of the aluminum electrode remained severe. As with Fig. 3a, reduced zinc diffusion resulted in an oxidized aluminum–Cu–Ni interface, directly affecting contact resistance.\u003c/p\u003e\n\u003cp\u003eAfter removing ZnO, the equivalent circuit of the thick-film printed aluminum electrode with a short zinc protective layer was constructed. The total resistance rose slightly to 134 mΩ; the Cu–Ni resistive layer increased to 44.2 mΩ; and each aluminum electrode rose slightly to 38 mΩ. Clearly, shortening the zinc protective layer below the Cu–Ni layer length slightly increased both oxidation and resistance of the aluminum electrodes and the Cu–Ni layer. Nevertheless, even though part of the Cu–Ni layer was exposed during high-temperature air sintering, the oxygen content and resistivity of the Cu–Ni resistive layer increased only slightly. This outcome is attributed to the lower aluminum electrode’s high oxide formation enthalpy, which consumed oxygen and helped protect the Cu–Ni layer from heavy oxidation during air sintering[12].\u003c/p\u003e\n\u003cp\u003eThe main resistance components of this structure are: two aluminum electrodes (38 mΩ each), aluminum–Cu–Ni contact resistance (6.9 mΩ), and the Cu–Ni alloy resistive layer (44.2 mΩ). The TCR remains primarily governed by the aluminum electrodes, and is comparable to that of the equal-length zinc protective layer resistor (≈1204 ppm/°C), still far exceeding the \u0026lt;300 ppm/°C requirement for conventional alloy resistors.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e2. Sputtered Aluminum Thin-Film Electrodes with a Zinc Protective Layer for Air-Fired Cu–Ni Resistors\u003c/u\u003e\u003c/p\u003e\n\u003cp\u003e(1) Zinc protective layer longer than the Cu–Ni resistor layer\u003c/p\u003e\n\u003cp\u003eFigures 5a and 5b show microstructural analyses of the aluminum end-electrode layer/Cu–Ni resistor layer/zinc protective layer and the Cu–Ni resistor layer/zinc protective layer of Cu–Ni resistors fabricated by air sintering at 850 °C for 10 minutes using sputtered aluminum thin-film electrodes with an extended zinc protective layer.\u003c/p\u003e\n\u003cp\u003eAs seen clearly in Fig. 5b, besides the upper zinc protective layer oxidizing to form ZnO and the formation of the underlying Cu–Ni alloy layer—as in the thick-film printed aluminum electrode sample of Fig. 2b—the zinc in the upper protective layer still diffuses partially into the underlying Cu–Ni alloy resistor layer. Figures 5a and 2a respectively show the cross-sections of sputtered aluminum thin-film electrodes and thick-film printed aluminum electrodes with a long zinc protective layer: a sandwich structure consisting of the upper zinc protective layer, middle Cu–Ni resistor layer, and lower aluminum end electrode. It is obvious that the sputtered aluminum thin-film electrode thickness of about 2–3 μm differs significantly from the thick-film printed aluminum electrode thickness of about 10–15 μm.\u003c/p\u003e\n\u003cp\u003eIt is also noteworthy that, regardless of whether sputtered thin-film or thick-film printed aluminum end electrodes are used, both show clear evidence of aluminum diffusing into the zinc protective layer. Furthermore, after co-firing at 850 °C in air with the Cu–Ni resistor layer, the sputtered aluminum thin-film electrode exhibits obvious oxidation. This affects the contact resistance between the sputtered aluminum thin-film end electrode and the Cu–Ni resistor layer.\u003c/p\u003e\n\u003cp\u003eAfter removing the upper ZnO protective layer, the resistance of the sputtered thin-film aluminum electrode and the Cu–Ni resistor layer was measured. Subtracting the resistances of the sputtered aluminum thin-film end electrode and the Cu–Ni resistor layer from the total resistance measured across both sputtered aluminum thin-film electrodes yields the contact resistance between the sputtered thin-film end electrode and the Cu–Ni resistor layer, enabling construction of the equivalent circuit of the entire resistor.\u003c/p\u003e\n\u003cp\u003eFor this Cu–Ni resistor, the total resistance was 128 mΩ; the Cu–Ni resistor layer resistance was 39.2 mΩ; the resistance of both sputtered aluminum thin-film end electrodes was 37.2 mΩ, close to that of the Cu–Ni resistor layer; and the contact resistance between the Cu–Ni resistor layer and the aluminum end electrode was 6.9 mΩ.\u003c/p\u003e\n\u003cp\u003eThus, the main resistance of this structure consists of the two sputtered thin-film aluminum end electrodes, the middle Cu–Ni alloy resistor layer, and the contact resistance between them. Because the Cu–Ni alloy resistor layer is sandwiched between the upper zinc protective layer and the lower sputtered aluminum electrode layer—and the oxidation enthalpy of zinc and aluminum is higher than that of copper and nickel—the Cu–Ni alloy resistor layer retains a resistance of 39.2 mΩ comparable to Cu–Ni alloy resistors fired in nitrogen.\u003c/p\u003e\n\u003cp\u003eThe sputtered aluminum thin-film end electrode initially measured about 10 mΩ[13] ut after fabrication of the Cu–Ni resistor with a long zinc protective layer and air firing at 850 °C (above the aluminum melting point of 660 °C), its resistance increased to 37.2 mΩ. This is due to the increased oxidation of the sputtered aluminum thin-film electrode during high-temperature air firing, as well as the reaction and diffusion of the sputtered aluminum thin-film electrode into the zinc protective layer, which reduces the thickness of the sputtered aluminum thin-film electrode.\u003c/p\u003e\n\u003cp\u003eOverall, the temperature coefficient of resistance (TCR) of this structure is mainly influenced by the two sputtered aluminum thin-film end electrodes. As a result, the TCR of this resistor structure reaches 900 ppm/°C—far exceeding the low-TCR requirement (\u0026lt;300 ppm/°C) typical of alloy resistors.\u003c/p\u003e\n\u003cp\u003e(2) Zinc protective layer equal in length to the Cu–Ni resistor layer\u003c/p\u003e\n\u003cp\u003eFigures 6a and 6b show microstructural analyses of the aluminum end-electrode layer/Cu–Ni resistor layer/zinc protective layer and the Cu–Ni resistor layer/zinc protective layer of Cu–Ni resistors fabricated by air sintering at 850 °C for 10 minutes using sputtered aluminum thin-film electrodes with a zinc protective layer of the same length as the Cu–Ni resistor layer.\u003c/p\u003e\n\u003cp\u003eCompared with Fig. 5b, where the zinc protective layer is longer than the Cu–Ni resistor layer, in Fig. 6b the zinc protective layer is shortened to match the Cu–Ni resistor layer length. Therefore, the ability to protect the Cu–Ni alloy resistor layer from oxidation during sintering is slightly reduced. In addition, although the lower layer is still a sputtered aluminum thin-film end electrode, its thickness is nearly an order of magnitude less than that of thick-film printed aluminum electrodes. This means that using a lower sputtered aluminum thin-film end electrode and an upper zinc protective layer to protect the middle Cu–Ni resistor layer at 850 °C in air results in a weaker oxidation resistance. Consequently, the oxidation of the middle Cu–Ni resistor layer increases and its resistance rises.\u003c/p\u003e\n\u003cp\u003eAfter removing the upper ZnO protective layer, the equivalent circuit of the entire resistor was constructed. For the Cu–Ni resistor fabricated by air sintering at 850 °C with sputtered aluminum thin-film electrodes and a zinc protective layer of equal length, the total resistance increased slightly to 132 mΩ; the Cu–Ni resistor layer resistance increased slightly to 50.8 mΩ. Compared with Fig. 5a, where the sputtered aluminum thin-film end electrode with a long zinc protective layer had a resistance of 37.2 mΩ, in Fig. 6a, where the zinc protective layer is of equal length, the sputtered aluminum thin-film end electrode resistance decreased slightly to 32.1 mΩ. This is mainly because shortening the zinc protective layer reduces its contact area with the sputtered aluminum thin-film end electrode; thus, during co-firing the diffusion of the sputtered aluminum thin-film end electrode into the zinc protective layer is reduced, lowering its resistance.\u003c/p\u003e\n\u003cp\u003eThis structure’s resistance is composed of the aluminum end electrodes (32.1 mΩ), the aluminum–Cu–Ni contact resistance (8.5 mΩ), and the middle Cu–Ni alloy resistor (50.8 mΩ). Its TCR (795 ppm/°C) is improved compared to the TCR (900 ppm/°C) of the previous long zinc protective layer sample.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e(3) Zinc protective layer shorter than the Cu–Ni resistor layer\u003c/p\u003e\n\u003cp\u003eFigures 7a and 7b show microstructural analyses of the aluminum end-electrode layer/Cu–Ni resistor layer/zinc protective layer and the Cu–Ni resistor layer/zinc protective layer of Cu–Ni resistors fabricated by air sintering at 850 °C for 10 minutes using sputtered aluminum thin-film electrodes with a shortened zinc protective layer.\u003c/p\u003e\n\u003cp\u003eAs shown in Fig. 7b, the upper zinc protective layer is shorter than the Cu–Ni resistor layer, providing even poorer protection against oxidation during sintering. The combined effect of the short protective layer and the thin aluminum end electrode further weakens the oxidation protection, leading to increased oxidation of the middle Cu–Ni resistor layer and a higher resistance.\u003c/p\u003e\n\u003cp\u003eAccording to Fig. 7a, compared with Fig. 6a (equal-length zinc protective layer), the upper Cu–Ni resistor layer of the aluminum end electrode in the short zinc protective layer sample is almost completely oxidized due to the lack of coverage. Meanwhile, the contact area between the sputtered aluminum thin-film end electrode and the short zinc protective layer decreases, reducing the diffusion of the sputtered aluminum thin-film electrode into the zinc protective layer[14]is means that after co-firing with the short zinc protective layer, the sputtered aluminum thin-film end electrode remains relatively intact, and its resistance decreases.\u003c/p\u003e\n\u003cp\u003eAfter removing the upper ZnO protective layer, the equivalent circuit of the Cu–Ni resistor fabricated by air sintering at 850 °C with sputtered aluminum thin-film electrodes and a short zinc protective layer was constructed. The total resistance increased to 146.4 mΩ; the Cu–Ni resistor layer resistance increased to 78.4 mΩ; and the resistance of the two aluminum end electrodes decreased to 25.9 mΩ.\u003c/p\u003e\n\u003cp\u003eThe resistance of this structure consists of the aluminum end electrodes (25.9 mΩ), the aluminum–Cu–Ni contact resistance (8.1 mΩ), and the middle Cu–Ni alloy resistor (78.4 mΩ). Its TCR dropped to 615 ppm/°C, approaching the low-TCR characteristic (\u0026lt;300 ppm/°C) typical of alloy resistors. This TCR result is mainly influenced by the middle Cu–Ni resistor layer (Cu–Ni TCR: 100 ppm/°C) with its high 78.4 mΩ resistance, while the influence of the sputtered aluminum thin-film end electrode (Al TCR: 3900 ppm/°C) with its lower 25.9 mΩ resistance is relatively small.\u003c/p\u003e\n\u003cp\u003e\u003cu\u003e3. Thick-Film Printed Silver Electrodes with Zinc Protective Layers for Air Firing of Cu–Ni Resistors\u003c/u\u003e\u003c/p\u003e\n\u003cp\u003e(1) Protective Zinc Layer Longer than Cu–Ni Resistive Layer\u003c/p\u003e\n\u003cp\u003eFigures 8a and 8b respectively show microstructural analyses of the silver terminal electrode layer–Cu–Ni resistive layer–zinc protective layer and of the intermediate Cu–Ni resistive layer–zinc protective layer of a thick-film printed silver electrode Cu–Ni resistor with a long zinc protective layer after air co-firing at 850 °C for 10 min.\u003c/p\u003e\n\u003cp\u003eAccording to Figure 8b, it is evident that, in addition to the top zinc protective layer being oxidized to a ZnO layer, a Cu–Ni alloy layer forms underneath but with an oxygen content higher than that of the thick-film printed aluminum electrode Cu–Ni resistor with a zinc protective layer fired in air shown in Figure 2b. The main difference is that the enthalpy of formation of oxidation of the lower silver terminal electrode differs from that of the aluminum terminal electrode in Figure 2b: it is lower than that of copper and nickel oxides. In this zinc–Cu–Ni–silver sandwich structure under high-temperature air firing, the intermediate Cu–Ni resistive layer is sandwiched between the top zinc protective layer and the lower silver terminal electrode. In practice, only the top zinc protective layer can protect the Cu–Ni layer from oxidation during high-temperature firing. The lower silver electrode not only fails to protect the Cu–Ni layer from oxidation but, because silver has a lower enthalpy of oxide formation than Cu and Ni, the Cu–Ni resistive layer must partially oxidize to protect the silver electrode from oxidation results in a slightly higher degree of Cu–Ni oxidation after co-firing at 850 °C[15].\u003c/p\u003e\n\u003cp\u003eAccording to Figure 8a, in addition to ZnO formation in the protective layer, the shape of the silver terminal electrode is well retained and its oxygen content is very low, indicating that no interdiffusion occurs among the silver terminal electrode, the zinc protective layer, and the Cu–Ni resistive layer, and that the silver electrode does not oxidize. The absence of oxidation in the silver terminal electrode is reflected in the contact resistance between the silver terminal electrode and the Cu–Ni resistive layer.\u003c/p\u003e\n\u003cp\u003eAfter removing the surface ZnO layer, the resistance of the silver terminal electrode and of the Cu–Ni resistive layer were measured. By subtracting the resistance of the silver electrodes and of the Cu–Ni resistive layer from the total resistance measured across both silver electrodes, the contact resistance between the silver terminal electrodes and the Cu–Ni resistive layer can be obtained, thus enabling construction of an equivalent circuit for the whole resistor. For this structure, the total resistance of the Cu–Ni resistor is 94 mΩ, the resistance of the Cu–Ni resistive layer is 85.05 mΩ, the two silver terminal electrodes show very low resistance at 3.47 mΩ, and the contact resistance between the Cu–Ni resistive layer and the silver terminal electrodes is only 1 mΩ. Because the Cu–Ni alloy resistive layer is sandwiched between the top zinc protective layer and the lower silver electrode to form a zinc–Cu–Ni–silver sandwich structure under high-temperature air firing, where the enthalpy of oxide formation of zinc is higher than that of Cu and Ni but that of silver is lower than that of Cu and Ni, the Cu–Ni alloy resistance of 85.05 mΩ is more than twice that of aluminum-electrode Cu–Ni alloy resistors fired in air or nitrogen (35.6 mΩ). In addition, since the 850 °C firing temperature is below the melting point of silver (961 °C), the thick-film silver electrode resistance (3.47 mΩ) is about ten times lower than that of thick-film aluminum electrodes (32 mΩ) or thin-film sputtered aluminum electrodes (25.9 mΩ). Therefore, for this structure the temperature coefficient of resistance (TCR) is mainly determined by the slightly higher oxygen content of the intermediate Cu–Ni resistive layer. Given that the TCR of Cu–Ni is about 100 ppm/°C[16], this resistor exhibits a TCR of 224 ppm/°C, which meets the requirement of low-TCR alloy resistors (\u0026lt; 300 ppm/°C).\u003c/p\u003e\n\u003cp\u003e(2) Protective Zinc Layer Equal in Length to Cu–Ni Resistive Layer\u003c/p\u003e\n\u003cp\u003eFigures 9a and 9b respectively show microstructural analyses of the silver terminal electrode layer–Cu–Ni resistive layer–zinc protective layer and of the intermediate Cu–Ni resistive layer–zinc protective layer of a thick-film printed silver electrode Cu–Ni resistor with a zinc protective layer equal in length to the Cu–Ni resistive layer after air co-firing at 850 °C for 10 min.\u003c/p\u003e\n\u003cp\u003eAccording to Figure 9b, in addition to the top zinc protective layer being oxidized to ZnO and the formation of a Cu–Ni alloy layer underneath, the oxygen content of the Cu–Ni alloy resistive layer is more severe than in Figure 8b, especially near both electrode ends. This results mainly from the shortened zinc protective layer having the same length as the Cu–Ni resistive layer, which slightly reduces the ability to protect the Cu–Ni alloy resistive layer from oxidation during high-temperature air firing. At the same time, co-firing of the Cu–Ni resistive layer with silver electrodes having lower enthalpy of oxide formation increases the oxygen content of the Cu–Ni resistive layer.\u003c/p\u003e\n\u003cp\u003eAccording to Figure 9a, no interdiffusion occurs among the silver electrode, the zinc protective layer, and the Cu–Ni resistive layer, and under co-firing the silver terminal electrode is protected by the higher oxide formation enthalpy of Cu–Ni. Thus, as in Figure 8b, the silver terminal electrode maintains its shape and shows no oxidation.\u003c/p\u003e\n\u003cp\u003eAfter removing the ZnO layer, an equivalent circuit was constructed. The total resistance of the Cu–Ni resistor slightly increases to 178 mΩ, with the Cu–Ni resistive layer resistance slightly increasing to 167 mΩ, the two silver terminal electrodes still showing very low resistance at 3.42 mΩ, and the contact resistance between the Cu–Ni resistive layer and the silver terminal electrodes slightly increasing to 2.07 mΩ. This increase in contact resistance is mainly due to the slightly higher oxidation of the Cu–Ni resistive layer near the silver terminal electrodes caused by shortening the zinc protective layer.\u003c/p\u003e\n\u003cp\u003eThis resistor consists of the two silver terminal electrode resistances (3.42 mΩ), the silver–Cu–Ni contact resistances (2.07 mΩ), and the intermediate Cu–Ni alloy resistance (167 mΩ). Its TCR is mainly influenced by the slightly higher oxygen content of the Cu–Ni resistive layer. Given that the TCR of Cu–Ni is about 100 ppm/°C, the thick-film printed silver-electrode Cu–Ni resistor with an equal-length zinc protective layer exhibits a TCR of 266 ppm/°C, which meets the low-TCR alloy resistor specification (\u0026lt; 300 ppm/°C).\u003c/p\u003e\n\u003cp\u003e(3) Protective Zinc Layer Shorter than Cu–Ni Resistive Layer\u003c/p\u003e\n\u003cp\u003eFigures 10a and 10b respectively show microstructural analyses of the silver terminal electrode layer–Cu–Ni resistive layer–zinc protective layer and of the intermediate Cu–Ni resistive layer–zinc protective layer of a thick-film printed silver electrode Cu–Ni resistor with a short zinc protective layer after air co-firing at 850 °C for 10 min.\u003c/p\u003e\n\u003cp\u003eAs shown in Figure 10b, because the zinc protective layer is shorter than the Cu–Ni resistive layer, its ability to protect the Cu–Ni resistive layer from oxidation during high-temperature air firing is further diminished. The oxygen content of the Cu–Ni alloy resistive layer is significantly higher than that of the long or equal-length zinc protective layers in Figures 8b and 9b.\u003c/p\u003e\n\u003cp\u003eAccording to Figure 10a, compared with Figure 9a, the Cu–Ni resistive layer above the silver terminal electrode is almost completely oxidized due to the lack of zinc protective layer coverage. Furthermore, because the lower silver electrode has a lower enthalpy of oxide formation than the Cu–Ni resistive layer, it further worsens the oxidation of Cu–Ni near the silver terminal electrode, especially nickel oxidation[17]. The increased oxidation of the Cu–Ni resistive layer near the silver terminal electrodes directly leads to increased contact resistance between the silver terminal electrodes and the Cu–Ni resistive layer.\u003c/p\u003e\n\u003cp\u003eIt is clear that for a thick-film printed silver electrode Cu–Ni resistor with a short zinc protective layer, the shortened zinc protective layer results in much greater oxidation of the Cu–Ni resistive layer. Unlike thick-film printed aluminum electrodes, where the high oxide formation enthalpy of aluminum can still protect the intermediate Cu–Ni layer even when the zinc protective layer is short, the lower silver electrode not only fails to protect the intermediate Cu–Ni layer but actually aggravates oxidation of the Cu–Ni resistive layer near the silver terminal electrode.\u003c/p\u003e\n\u003cp\u003eAfter removing the ZnO layer, an equivalent circuit was constructed. The total resistance of the Cu–Ni resistor dramatically increases to 3 Ω. Because the Cu–Ni resistive layer is much more oxidized, especially near the two silver terminal electrodes compared to the middle Cu–Ni resistive layer, unlike the previous long and equal-length zinc protective layer cases where the Cu–Ni alloy layer could be treated as a single resistor, here the Cu–Ni resistive layer can be divided into three resistors: a slightly oxidized middle Cu–Ni resistive layer and two highly oxidized Cu–Ni resistive layers near the silver terminal electrodes.\u003c/p\u003e\n\u003cp\u003eUnlike the previous equivalent circuits, which consisted of five resistors (two terminal electrode resistances, two contact resistances, and the middle Cu–Ni resistance), this structure with a short zinc protective layer consists of seven resistors: two terminal electrode resistances, two contact resistances, two highly oxidized Cu–Ni resistances near the silver electrodes, and the slightly oxidized middle Cu–Ni resistance. The resistor is composed of the two silver terminal electrode resistances (3.53 mΩ), the silver–highly oxidized Cu–Ni contact resistances (4 mΩ), the highly oxidized Cu–Ni alloy resistances (1.36 Ω), and the slightly oxidized middle Cu–Ni alloy resistance (265 mΩ). Its TCR is mainly determined by both the highly oxidized Cu–Ni alloy resistances near the two silver terminal electrodes and the slightly oxidized middle Cu–Ni alloy resistance. This structure shows a TCR of 251 ppm/°C, satisfying the low-TCR alloy resistor specification (\u0026lt; 300 ppm/°C). Merely changing the zinc protective layer length to be shorter than the Cu–Ni resistive layer length can raise the resistor value from several hundred milliohms to several ohms while still maintaining a low TCR, which represents a major technological breakthrough for fabricating high-resistance Cu–Ni alloy resistors with low TCR.\u003c/p\u003e"},{"header":"IV. Conclusions","content":"\u003col\u003e\n \u003cli\u003eWhether using thick-film printed aluminum electrodes or thin-film sputtered aluminum electrodes with zinc protective layers for air firing of Cu–Ni resistors, the intermediate Cu–Ni resistive layer is sandwiched between the top zinc protective layer and the lower aluminum electrode. Because the oxide formation enthalpies of zinc and aluminum are higher than those of the Cu–Ni resistive layer, the Cu–Ni alloy resistance (32 mΩ) is comparable to that of Cu–Ni alloy resistors fired in nitrogen. This shows that in this zinc protective layer–Cu–Ni resistive layer–aluminum electrode sandwich structure under high-temperature air firing, regardless of whether the zinc protective layer is longer or shorter than the intermediate Cu–Ni resistive layer, the intermediate Cu–Ni resistive layer is essentially sintered in a reducing atmosphere due to the protection of the top zinc protective layer and the aluminum electrode. On the other hand, in the zinc–Cu–Ni–aluminum sandwich structure fired in air at 850 °C, because this exceeds the melting point of aluminum (660 °C), the oxidation degree of the aluminum terminal electrode increases, and aluminum diffuses into the zinc protective layer at the interface. Both factors lead to an increase in the aluminum terminal electrode resistance comparable to that of the Cu–Ni resistive layer. The TCR of the aluminum terminal electrode (3900 ppm/°C) dominates the overall TCR, so the aluminum-electrode Cu–Ni resistor fired in air with a zinc protective layer exceeds the low-TCR specification (\u0026lt; 300 ppm/°C).\u003c/li\u003e\n\u003c/ol\u003e\n\u003col start=\"2\"\u003e\n \u003cli\u003eFor thick-film printed silver electrodes with zinc protective layers fired in air, when the top zinc protective layer is longer than or equal in length to the Cu–Ni resistive layer, in the zinc–Cu–Ni–silver sandwich structure under high-temperature air firing only the top zinc protective layer can protect the Cu–Ni from oxidation; the lower silver electrode not only cannot protect Cu–Ni from oxidation but, because its oxide formation enthalpy is lower than that of Cu–Ni, causes the Cu–Ni resistive layer to partially oxidize to protect the silver electrode. In addition, since the 850 °C firing temperature is below the melting point of silver (961 °C), the thick-film silver terminal electrode maintains a very low resistance of 3.47 mΩ. Thus, the TCR of the overall resistor is mainly influenced by the slightly higher oxygen content of the intermediate Cu–Ni resistive layer (100 ppm/°C). The thick-film printed silver electrode Cu–Ni resistor with a zinc protective layer fired in air can achieve a TCR of 224 ppm/°C, satisfying the low-TCR specification (\u0026lt; 300 ppm/°C).\u003c/li\u003e\n\u003c/ol\u003e\n\u003col start=\"3\"\u003e\n \u003cli\u003eFor thick-film printed silver electrodes with zinc protective layers fired in air, when the top zinc protective layer is shorter than the Cu–Ni resistive layer, the Cu–Ni resistive layer above the silver terminal electrode is almost completely oxidized due to lack of zinc coverage, and because the lower silver electrode has a lower oxide formation enthalpy than the intermediate Cu–Ni resistive layer, it further aggravates oxidation of Cu–Ni near the silver terminal electrode, especially nickel oxidation. This leads to a dramatic increase in total resistance to 3 Ω. This resistor is composed of the two silver terminal electrode resistances (3.53 mΩ), the silver–highly oxidized Cu–Ni contact resistances (4 mΩ), the highly oxidized Cu–Ni alloy resistances (1.36 Ω), and the slightly oxidized middle Cu–Ni alloy resistance (265 mΩ). Its TCR (251 ppm/°C) is mainly influenced by both the highly oxidized Cu–Ni alloy resistances near the two silver terminal electrodes and the slightly oxidized middle Cu–Ni alloy resistance, satisfying the low-TCR specification (\u0026lt; 300 ppm/°C). Merely shortening the zinc protective layer relative to the Cu–Ni resistive layer can raise the resistor value from several hundred milliohms to several ohms while still maintaining a low TCR, representing a major technological breakthrough for producing high-resistance Cu–Ni alloy resistors with low TCR.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eConflict of Interest Statement\u003c/h2\u003e\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding Statement\u003c/h2\u003e\u003cp\u003eThe author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by National Science and Technology Council [NSTC112-2221-E-006-064]\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eChing Feng Chien, . Zihao Lin and Wen Hsi Lee conceived the study. Zihao Lin developed the theoretical framework. Ching Feng Chien performed the experiments, analyzed the data, and wrote the manuscript. Wen Hsi Lee contributed to the final version of the manuscript and supervised the project.\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e\u003cp\u003eThe authors confirm that the data supporting the findings of this study are available within the article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eT. Sumida, \"Recent Advances in Thick-Film Resistors and Target Applications,\" in IEEE Power Electronics Magazine, vol. 9, no. 1, pp. 70-72, Mar. (2022).\u003c/li\u003e\n\u003cli\u003eHrovat, M., \u0026amp; Jan, \u0026ldquo;An Investigation of Thick Film Resistor Materials' Properties During the Firing Process\u0026rdquo; Microelectronics International, 4(3), 25-29.(1987)\u003c/li\u003e\n\u003cli\u003eWen-His Lee,\u0026rdquo; Investigation of a copper\u0026ndash;nickel alloy resistor using co-electrodeposition\u0026rdquo;,Journal of Applied Electrochemistry 50(12), May (2020)\u003c/li\u003e\n\u003cli\u003eC. R. Kuo; Tzu-Chiang Kuo Wen-Hsi Lee＂A Novel Fabricating a Thick Film Cu-Ni Alloy Resistor by Screen Printing an Al Electrode and Galvanic Replacement Reaction＂IEEE Transactions on Components, Packaging and Manufacturing Technology 11, (11), Nov. (2021)\u003c/li\u003e\n\u003cli\u003eJiri Hlina＂Study of Copper-Nickel Nanoparticle Resistive Ink Compatible with Printed Copper Films for Power Electronics Applications＂Materials. 20;14(22):7039. Nov.(2021)\u003c/li\u003e\n\u003cli\u003eAjay D. Pingale＂Recent researches on Cu-Ni alloy matrix composites through electrodeposition and powder metallurgy methods: A review＂Materialstoday Proceedings,47, (11), 3301-3308, (2021)\u003c/li\u003e\n\u003cli\u003eWen-Hsi Lee, S. W. Chang, Narendra Gharini Puteri＂Air-sintered copper-nickel resistor with aluminum layer for oxidation prevention, MRS Communications,(6]), 1301-1306, (2024)\u003c/li\u003e\n\u003cli\u003eNwaeju, C.C., et al., Structural and properties evolution of copper\u0026ndash;nickel (Cu\u0026ndash;Ni) alloys: a review of the effects of alloying materials. Mat\u0026eacute;riaux \u0026amp; Techniques, 2021. \u003cstrong\u003e109\u003c/strong\u003e(2): p. 204.\u003c/li\u003e\n\u003cli\u003eRen, J., et al., Effect of Different Heat Treatment Processes on the Microstructure and Properties of Cu-15Ni-3Al Alloys. Materials, 2025. \u003cstrong\u003e18\u003c/strong\u003e(12): p. 2678.\u003c/li\u003e\n\u003c/ol\u003e\n\u003col start=\"10\"\u003e\n\u003cli\u003ePola, A., M. Tocci, and F.E. Goodwin, Review of microstructures and properties of zinc alloys. Metals, 2020. \u003cstrong\u003e10\u003c/strong\u003e(2): p. 253.\u003c/li\u003e\n\u003cli\u003eSchaffer, G. and B. Hall, The influence of the atmosphere on the sintering of aluminum. Metallurgical and Materials Transactions A, 2002. \u003cstrong\u003e33\u003c/strong\u003e(10): p. 3279-3284.\u003c/li\u003e\n\u003cli\u003eLi, D., et al., Study on ultrathin silver film transparent electrodes based on aluminum seed layers with different structures. Nanomaterials, 2022. \u003cstrong\u003e12\u003c/strong\u003e(19): p. 3540.\u003c/li\u003e\n\u003cli\u003eCzerwinski, F., Aluminum alloys for electrical engineering: a review. Journal of Materials Science, 2024. \u003cstrong\u003e59\u003c/strong\u003e(32): p. 14847-14892.\u003c/li\u003e\n\u003cli\u003eYarborough, B., Temperature coefficient of resistance for current sensing. Vishay Dale., Los Angeles, CT, USA, Tech. Rep, 2020. \u003cstrong\u003e30405\u003c/strong\u003e.\u003c/li\u003e\n\u003cli\u003eBanks, C.E., et al., Fundamentals of screen-printing electrochemical architectures. Screen-printing electrochemical architectures, 2016: p. 13-23.\u003c/li\u003e\n\u003cli\u003eStegmann, T., et al., Interfacial Effects of Surface Roughness and Topography on the Bond Strength of Silver-Sintered Joints on Copper Substrates. Journal of Electronic Materials, 2025. \u003cstrong\u003e54\u003c/strong\u003e(5): p. 4143-4153.\u003c/li\u003e\n\u003cli\u003eZhang, W., et al., Experimental study on the thermal volatilization and condensation of zinc at 10 Pa and 200 Pa. Journal of Materials Research and Technology, 2020. \u003cstrong\u003e9\u003c/strong\u003e(3): p. 3590-3597.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable1 Compariosn of dielectric properties of multilayer PZT device cofired with \u0026nbsp;inner electrode of the noble metal Ag/Pd and the base metal Cu/Al ( 40/60wt%)\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;Table (I) \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cimg width=\"424\" height=\"183\" 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\" 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circuit","lastPublishedDoi":"10.21203/rs.3.rs-7872541/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7872541/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study mainly aims to solve the issue of selecting suitable electrode materials for Cu\u0026ndash;Ni alloy resistors that are sintered at high temperatures in air, enabled by a zinc protective layer covering the Cu\u0026ndash;Ni paste to replace the reducing atmosphere. Because the electrodes connecting the Cu\u0026ndash;Ni alloy resistors are directly exposed to high temperatures in air during sintering, three types of electrode materials were selected: thick-film printed aluminum electrodes, sputtered thin-film aluminum electrodes, and thick-film printed silver electrodes. In addition, three variations in the length of the zinc protective layer covering the Cu\u0026ndash;Ni paste were examined\u0026mdash;equal to, longer than, or shorter than the Cu\u0026ndash;Ni resistive layer.\u003c/p\u003e\u003cp\u003eFor both thick-film printed aluminum electrodes and sputtered thin-film aluminum electrodes co-fired with zinc-protected Cu\u0026ndash;Ni resistor paste at 850\u0026deg;C for 10 minutes, the portions of the aluminum electrodes not in contact with the Cu\u0026ndash;Ni paste were partially oxidized, resulting in increased electrode resistance. leading to a larger temperature coefficient of resistance (TCR) for the Cu\u0026ndash;Ni alloy chip resistor (1390 ppm/℃).\u003c/p\u003e\u003cp\u003eWhen thick-film printed silver electrodes were co-fired with zinc-protected Cu\u0026ndash;Ni resistor paste at 850\u0026deg;C for 10 minutes, the portions of the silver electrodes in contact with the Cu\u0026ndash;Ni resistor paste were protected from oxidation due to the higher oxide formation enthalpy of Cu\u0026ndash;Ni compared to silver. Because the silver electrode combined with the zinc-protected, air-sintered Cu\u0026ndash;Ni alloy resistor exhibited extremely low electrode and contact resistances, the resulting resistor showed an excellent TCR of about 224 ppm/℃。\u003c/p\u003e\u003cp\u003eThis study successfully fabricated zinc-protected Cu\u0026ndash;Ni alloy resistors sinterable in air at 850\u0026deg;C using silver electrodes, achieving superior resistance characteristics. Furthermore, by adjusting the relative lengths of the zinc protective layer and the Cu\u0026ndash;Ni resistive layer, the oxidation degree of the Cu\u0026ndash;Ni resistive layer could be tuned to adjust its resistance from hundreds of micro-ohms to several ohms.\u003c/p\u003e","manuscriptTitle":"Effect of electrodes on the characteristics of copper-nickel alloy resistors covered with a zinc protective layer and sintered in air","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-05 15:45:13","doi":"10.21203/rs.3.rs-7872541/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f60d11ed-510f-4b7e-91b8-7c558f680568","owner":[],"postedDate":"November 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-12-29T02:08:48+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-05 15:45:13","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7872541","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7872541","identity":"rs-7872541","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}