Semiconductor device having a ridge or groove

摘要

The invention provides a semiconductor device having a structure wherein a layer comprising at least AlWGa1-WAs is formed on a substrate and a second etching stop layer, a first etching stop layer and a layer comprising AlYGa1-YAs are deposited on the layer comprising AlWGa1-WAs in the described order, with a portion of the layer comprising AlYG1-YAs and a portion of the first etching stop layer being removed. This structure enables a desired ridge shape to be fabricated with good quality and allows for free selection of the Al mixed crystal ratio of the layer to be etched, and makes it possible to form the re-growth interface of GaAs. Thus, the qualty of crystal of the re-grown portion can be improved.