METHOD FOR MANUFACTURING A SEMICONDUCTOR DEVICE

摘要

A method for manufacturing a semiconductor device is provided to improve productivity of a large-sized SOI layer by preventing an etching state of a Si layer in contact with a cavity part. A SiGe layer is formed on a substrate(1). A Si layer(13) is formed on the SiGe layer. A groove for exposing a lateral surface of the SiGe layer is formed by etching partially the Si layer and the SiGe layer. A cavity part(25) is formed between the substrate and the Si layer by etching the SiGe layer through the groove. In the process for forming the cavity part, the cavity part is formed partially by supplying a fluorinated nitric acid solution to the substrate and etching the SiGe layer. The fluorinated nitric acid solution is removed from the cavity part. The SiGe layer is etched by supplying the fluorinated nitric acid solution to the cavity part.