The effect of oxygen incorporation in ela poly-Si films and its relation to poly-Si TFT device performance

摘要

In this work we have systematically investigated excimer-laser-pannealing of amorphous silicon in vacuum, air and inert gases (argon, notrogen and helium). We found that control of xoygen contamination is a key process for improving the FTF performance. We shoed that vacuum is not necessary for the realization of high performance TFTs and that inert gas ambient could be implemented equally well. The deleterious effects of ELA in air ambient were identified to be the increased density for both grain boundary and inter-grain efects. The former could be compensated, to a sertain extent, by hydrogen passivation, but the latter could not. An oxygen conentration of about 0.5at