Emitter Profile Tailoring by Gas Flux Variation in Tube Furnace POCl3–Diffusion and Analysis of the Phosphosilicate Glass

摘要: We analyze possibilities and difficulties of forming POCl3-diffused emitters for industrial application with low recombination by reducing the maximum phosphorus concentration in emitter. For this purpose we vary reactants process tube furnace. Both life time samples solar cells are processed reference proposed variation. During processing take special care a detailed characterisation phosphosilicate glass assess its basic properties. observe gain cell efficiency 0.2% absolute on standard screen-printed silicon fabricated improved emitters. Diffusions provide higher open circuit voltages efficiencies. The fill factor level is maintained, since contact resistance does not increase although peak doping reduces from ~8 to ~5x10 20 cm -3 . A correlation between saturation current observed. Increasing deposition expense drive-in allows mitigating negative impact sheet homogeneity along boat (suitable 200 Wafers).