The Effects of Cu on Field Aided Lateral Crystallization (FALC) of Amorphous Silicon (a-Si) Films

Abstract

ABSTRACTA novel concept of field aided lateral crystallization (FALC) and the effects of Cu on FALC of amorphous silicon (a-Si) were investigated. Cu was found to induce the lateral crystallization toward a metal-free region as well as the crystallization of a-Si in contact with Cu. In particular, the lateral crystallization caused by Cu was noticeably accelerated at the negative electrode side in every pattern with an aid of electric field, while it was retarded at the positive electrode side. The occurrence of Cu-FALC phenomenon was interpreted in terms of dominant diffusing species (DDS) in the reaction between metal and Si. The FALC velocity increased with the applied field intensity and the annealing temperature. The crystallization of a-Si was achieved at temperatures as low as 375°C when the annealing time increased in the presence of high electric field, above 30V/cm. Therefore, we could demonstrate the possibility of low temperature (<500°C) polycrystalline silicon (poly-Si) crystallization using Cu as a mediator in FALC technology.