Effect of high temperature steam annealing for SiO2 passivation

We introduced high-temperature steam annealing (HSA) as a low-cost acid eff ective postannealing method for c-Si solar cell processing. The annealing e ffects were analyzed by measuring effective lifetime and C-V characteristic s and were compared with the effects of forming gas annealing (FGA) and hyd rogen-radical annealing (I-IRA). By using this method, effective lifetime o f a SiO2-coated wafer was increased in a very short annealing time compared to the conventional FGA. It was determined that the improvement of lifetim e by HSA can be attributed to the decrease of interface state density. (C) 2001 Elsevier Science B.V. All rights reserved.