The Characterization of Amorphous AZO-n/Si-p Hetrojunction Diode for Solar Cell Application

Abstract The aim of the present study is to verify the effect of annealing temperature variation on zinc oxide doped with aluminum (AZO) thin films deposited on p-type silicon (Si) substrates. Here, AZO/p-Si heterojunction was annealed in nitrogen environment and its structural, electrical, and optical characterizations were investigated. The results of XRD patterns showed the amorphous structure of AZO thin films. FE-SEM images illustrated the increase of grain size by increasing annealing temperature up to 500oC. The reflectance analysis showed that for this annealing temperature, that the energy band gap of AZO thin film was moved to higher energy level. The electrical properties were investigated by I–V measurement carried out in the light at room temperatures. The short circuit current (ISC), ideality factor, saturation current, and open circuit voltage (VOC) of the AZO/p-Si heterojunction strongly depended on annealing conditions due to charge carrier trapping and density of defect on interface. By considering IR and IF as reverse and forward current, the ration of IF/IR had the maximum value at 1 V which was belonged to n-AZO/p-Si heterojunction at 500oC annealing temperature.