Investigation and Development of Industrial Feasible Cleaning Sequences Prior to Silicon Nitride Deposition Enhancing Multicrystalline Silicon Solar Cell Efficiency

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 1914-1918
This paper gives an insight into the effects of different wet chemical cleaning procedures prior to the silicon nitride deposition. The investigation of different emitters (with respect to sheet resistances and diffusion methods) showed the same cell parameter trends concerning different cleaning treatments. It was also found that cleanings with a strong influence on the cell parameters lead to pronounced changes in the emitter sheet resistance as well. This makes emitter material abrasion a likely candidate for an explanation of the observed effects on cell level. Combining cell results with internal quantum efficiencies, sheet resistance measurements and spreading resistance analyses allow for a first estimation concerning valuable combinations of emitters and cleanings.