A novel phosphorus diffusion process for front-side P–N junction fabrication in PERC solar cells

Abstract

P–N junction technology underlies photovoltaic conversion in passive emitter and rear cell (PERC) solar cells. Although the front-side phosphorus diffusion method for creating P-type PERC cells is well researched, avenues for innovation persist. We introduce a P–N junction fabrication technique for PERC solar cells via precisely controlling the surface doping concentration and junction depth. Through pressure modulation and carefully selected annealing duration at a defined temperature, the technique yields a P–N junction with a surface doping concentration of 2.37 × 1020 cm−3 and a junction depth of 0.29 μm on the front surface of PERC cells. Compared to conventional diffusion processes, our approach results in an average increase of 1.3 mV in open-circuit voltage, 20 mA in short-circuit current, and an efficiency gain of 0.05 %. The maximum efficiency achieved is 23.68 %, representing an improvement of 0.16 %.