Effect of Annealing time on structural, morphological, linear and nonlinear optical properties of spin-coated CuInS 2 (CIS) thin film for opto-electronic applications

Effect of Annealing time on structural, morphological, linear and nonlinear optical properties of spin-coated CuInS 2 (CIS) thin film for opto-electronic applications | 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 Annealing time on structural, morphological, linear and nonlinear optical properties of spin-coated CuInS 2 (CIS) thin film for opto-electronic applications Hervé Joël Tchognia Nkuissi, Bouchaib Hartiti, Mondjou Georges Constant Beh, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9359978/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 P-type CuInS 2 (CIS) thin films are promising candidates for use as absorber layers in thin film photovoltaics. They have attracted considerable interest due to their high photovoltaic conversion efficiency and ease of synthesis using simple and low-cost techniques. In this study, CIS was synthesized and deposited on glass substrates by sol gel spin coating method. Thin films were annealed at 350°C for 10min, 15 min, and 20 min without sulfurization. The synthesized films were characterized using various techniques such X-Ray Diffraction (XRD), Raman Spectroscopy (RS), Scanning Electron Microscope (SEM), UV-visible spectrophotometry (UV-Vis) and Four-Point Probe technique (FPP) to investigate the effect of annealing time on their structural, morphological, linear and nonlinear optical properties. XRD spectra showed that the intensity of the (112) peak increases with annealing time, revealing good crystallinity of the films. Raman analysis revealed a unique peak located at 298.12 position, thus confirming a good formation of CIS. SEM micrographs revealed densely packed grains uniformly distributed over the entire surface of the substrate for the film annealed during 20 min. Various optical parameters including static refractive index (n 0 ), oscillation energy (E 0 ), dispersion energy (E d ), and bandgap energy (E g ) were calculated. The bandgap energy of CIS decreases from 1.53 eV to 1.47 eV as the annealing time increases. In addition, we analyzed the third-order nonlinear susceptibilities (χ (3) ) and the nonlinear refractive index (n 2 ). Finally, Four-Point Probe technique confirmed the other results by revealing that the best annealing time for a suitable electrical conductivity is 20 min. CuInS2 Sol-gel annealing time sulfur-free linear/nonlinear optical properties Full Text 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-9359978","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":621566231,"identity":"e0fa3c84-993f-49c7-a632-8b4ed3dcd085","order_by":0,"name":"Hervé Joël Tchognia 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properties","lastPublishedDoi":"10.21203/rs.3.rs-9359978/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9359978/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eP-type CuInS\u003csub\u003e2\u003c/sub\u003e (CIS) thin films are promising candidates for use as absorber layers in thin film photovoltaics. They have attracted considerable interest due to their high photovoltaic conversion efficiency and ease of synthesis using simple and low-cost techniques. In this study, CIS was synthesized and deposited on glass substrates by sol gel spin coating method. Thin films were annealed at 350\u0026deg;C for 10min, 15 min, and 20 min without sulfurization. The synthesized films were characterized using various techniques such X-Ray Diffraction (XRD), Raman Spectroscopy (RS), Scanning Electron Microscope (SEM), UV-visible spectrophotometry (UV-Vis) and Four-Point Probe technique (FPP) to investigate the effect of annealing time on their structural, morphological, linear and nonlinear optical properties. XRD spectra showed that the intensity of the (112) peak increases with annealing time, revealing good crystallinity of the films. Raman analysis revealed a unique peak located at 298.12 position, thus confirming a good formation of CIS. SEM micrographs revealed densely packed grains uniformly distributed over the entire surface of the substrate for the film annealed during 20 min. Various optical parameters including static refractive index (n\u003csub\u003e0\u003c/sub\u003e), oscillation energy (E\u003csub\u003e0\u003c/sub\u003e), dispersion energy (E\u003csub\u003ed\u003c/sub\u003e), and bandgap energy (E\u003csub\u003eg\u003c/sub\u003e) were calculated. The bandgap energy of CIS decreases from 1.53 eV to 1.47 eV as the annealing time increases. In addition, we analyzed the third-order nonlinear susceptibilities (χ\u003csup\u003e(3)\u003c/sup\u003e) and the nonlinear refractive index (n\u003csub\u003e2\u003c/sub\u003e). 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