The passivation of Fe-related hole traps in p-type material was investigated by using deep-level transient spectroscopy and recombination lifetime measurements. After H ion implantation, all of the deep-level transient spectroscopy peaks which were related to Fe impurities had disappeared. This indicated that implanted H passivated the Fe-B pair as well as other Fe-related hole traps which were not passivated by a H plasma treatment. On the other hand, 2 types of hole trap were produced at Ev + 0.23eV and Ev + 0.38eV by H ion implantation. The recombination lifetime increased from 3 to 18s (about 45% of that in non-contaminated samples) as a function of implantation dose. It peaked at a dose of 1015/cm2. A decrease in recombination lifetime beyond this dose was attributed to hole traps which were created by ion implantation.

M.Kouketsu, K.Watanabe, S.Isomae: Materials Science Forum, 1995, 196-201, 861-6