Rapid Photothermal Processing for Silicon Solar Cells Fabrication

In our report we demonstrated the advantage of the rapid photothermal processing (RPP) technology compare to conventional furnace technology for solar cells fabrication: short time, low thermal budget and low temperature processing, high heating-cooling rates. The n⁺ -p-Si junctions were obtained from electrochemical deposited P source by rapid photothermal processing enhanced diffusion for 16 s at 900 degC and 1000 degC. The emitter sheet resistivity decreased from 1100 Omega/sq, RPP duration 60 s to 340 Omega/sq, RPP duration 200s at 999 degC. The concentration profiles of P in Si after RPP enhanced diffusion were analyzed. The regime of emitter ohmic contact formation is RPP at 310 degC for 8-10s. The photoelectrical parameters of the obtained n⁺-p and p⁺-n-Si photovoltaic cell are respective FF=33%, =4.1% and FF=40%, =1.1%. The obtained results demonstrated that all steps of the n⁺-p and p⁺-n Si solar cells fabrication can be realized by the rapid photothermal processing technology