Improved Gettering Efficiency of Ni from Nickel-Mediated Crystallization Silicon Using Phosphorus-Doped Amorphous Silicon

Abstract

Ni-metal-induced lateral crystallization (NILC) has been utilized to fabricate polycrystalline silicon thin-film transistors. However, the NILC process often leads to Ni and NiSi 2 precipitates being trapped. In this study, two kinds of films were used as gettering layers: (1) amorphous Si and (2) phosphorusdoped amorphous Si. After annealing at 550°C for 12 h, it was found that phosphorous dopant did improve the gettering efficiency of amorphous Si.

Simultaneous gettering and emitter formation in multicrystalline-Si wafers by annealing phosphorus doped amorphous silicon compounds

“…Gettering of metal impurities from deposited amorphous silicon ͑a-Si͒ was already reported in patents 2-4 and in a publication. 5 Emitter diffusion from phosphorus doped amorphous layers was demonstrated 6 without analyzing the gettering performance. Our process provides the simultaneous formation of an emitter and getters metallic impurities and will eventually also provide antireflection properties.…”