A Study on Cu(In,Ga)Se₂ Thin-Film Characteristics During Three-Stage Process Using Real-Time Substrate Monitoring

摘要

In this study, to analyze the effect of the second stage (Cu-Se) deposition time on CIGS property, the experiment of controlling the time of the second stage was conducted. Especially, very low values were found for device properties when it was 3300s and 3500s in the second stage. It was observed that excess Cu_2-xSe diffused excessively on the surface of the thin film, causing a lot of pores and voids on the surface. With the same evaporation ratio for each source of Cu, In, Ga, and Se, it is very important to apply the 2700s process time for the second stage in order to produce high-efficiency device. The efficiency property of device was checked through solar-simulator (AM1.5G, 100 mW/cm2 at 25°C). In case the process time of the second stage was 2700s, efficiency was as following: 10.1%, V_oc: 0.53V, J_sc: 33.5 mA/cm3, fill-factor: 57.2%. The analysis results obtained in this study are expected to be useful for various domestic and overseas research which aim to make high-efficiency solar cells based on proper variation of the second-stage processing time.