Low-temperature crystallization of amorphous silicon using Cu field-aided lateral crystallization at 350°C

Abstract

The crystallization of amorphous silicon (a-Si) was achieved by field-aided lateral crystallization (FALC). Under the influence of an electric field, Cu is found to drastically enhance the lateral crystallization velocity of a-Si. When an electric field of 30 V/cm was applied to selectively Cu-deposited a-Si films during heat treatment at 350°C, dendrite-shaped crystallization of a-Si progressed toward the Cu-free region, and the crystallization from the negative electrode side toward the positive electrode side was accelerated. The Cu-FALC polycrystalline-silicon (poly-Si) film has a crystalline volume fraction of 58% with 300-nm-long, rod-shaped grains. Low-temperature crystallization of a-Si in an electric field appears to be caused by enhanced migration of the Cu ions in the a-Si region.