MERCURY-SENSITIZED HYDROGEN RADICAL PHOTOETCHING OF HYDROGENATED AMORPHOUS-SILICON

A study of the etching of hydrogenated amorphous silicon films has bee n carried out by using hydrogen radical produced by mercury-photosensi tization of hydrogen gas. There was found it be an incubation period b efore etching began, and the incubation period depended on surface pre treatment conditions. It can be explained that the variation in incuba tion period strongly depend on unevenness of the a-Si:H surface. It ha s also been found that the actual etching rate of undoped a-Si:H incre ases with decreasing the substrate temperature. The authors consider t hat surface reaction, that is, adsorption of hydrogen radical, is domi nant in this etching process.