SELECTIVE ETCHING OF COMPOUND SEMICONDUCTOR, SELECTIVE ETCHING OF NITRIDE COMPOUND SEMICONDUCTOR, AND SEMICONDUCTOR DEVICE AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To etch a nitride compound semiconductor or a compound semiconductor selectively with respect to a base by oxidizing the surface of the nitride compound semiconductor which includes aluminum or the compound semiconductor including aluminum at or prior to etching and then etching the nitride compound semiconductor or the semiconductor in vapor phase thermochemically.;SOLUTION: With the use of etching gas which is a mixture of a first gas comprising halogen gas and halogen compound gas, a second gas comprising at least one of hydrogen gas and inactive gas, and an oxidizing gas, etching is conducted thermochemically with a compound semiconductor which includes aluminum as a base layer. For example, after a SiO2 film 8 in a gate electrode formation region is removed, thermochemically etching is conducted, using an etching gas which is a mixed gas of HC1 and N2 including O2. When an n+-type GaN layer 7 is etched and thereby an n-type AlGaN layer 6 in a lower layer is exposed, the layer 6 is oxidized with O2, thereby an oxide film 11 is formed and etching is formed stopper completely.;COPYRIGHT: (C)2000,JPO