Laser dehydrogenation/crystallization of plasma-enhanced chemical vapor deposited amorphous silicon for hybrid thin film transistors

Abstract

A low temperature process for laser dehydrogenation and crystallization of hydrogenated amorphous silicon (a-Si:H) has been developed. This process removes hydrogen by laser irradiations at three energy steps. Studies of hydrogen out-diffusion and microstructure show that hydrogen out-diffusion depends strongly on film structure and the laser energy density. Both high quality and low leakage bottom gate polycrystalline silicon and a-Si:H thin film transistors were monolithically fabricated on the same Corning 7059 glass substrate with a maximum process temperature of only 350 °C.