6 inch High efficiency back contact crystalline Si solar cell applying heterojunction and thinfilm technology

Abstract

We have developed a 6 inch heterojunction interdigitated back contact (HJBC) solar crystalline Si cell by applying our heterojunction technology and thinfilm technology. To form rear junction and front side passivation, we applied our heterojunction technology that allows efficiency of 24.5% with top/rear contact heterojunction solar cell. To secure this high quality passivation during the HJBC solar cell fabrication process, we have developed deposition technology of insulator layer originally used in thinfilm silicon solar cells. Furthermore, new structure has been designed to drastically suppress the rear electrode resistance. By adapting all these technologies, our HJBC solar cell has reached conversion efficiency of 24.91% independently confirmed at AIST (V OC =737 mV, I SC =10.07 A, FF=80.2 %, P MAX =5.95 W) under 1 sun illumination by total area measurement (239.0 cm2).