Interdigitated front contact solar cells fabricated by CMOS process technologies

We have fabricated novel interdigitated front contact structure silicon solar cells by using CMOS process technologies. Shallow emitter junction process using ion implantations and low leakage front contact process using barrier metals were developed. Front local base contact employed self-aligned spacer isolation technologies between emitter and base contacts. And we adjusted these with fine-pattern interdigitated grids to increase energy conversion efficiency. Inverted pyramid texturing, double anti-reflection coating, and trapezoidal metal etch technologies were integrated to increase photo-generated currents. Advanced module fabrication was developed for our cell structure. Integrating these new technologies, we have recorded maximum module efficiency of 20.1% in our laboratory.