Patent ID: 7678594

Claim:
A fabrication method for an integrated optical device having a first semiconductor optical element that is provided on a first region of a main face of a substrate and a second semiconductor optical element that is provided on a second region of the main face of the substrate and that is optically coupled to the first semiconductor optical element, comprising the steps of: forming a first III-V compound semiconductor layer containing an Al element on the main face of the substrate; forming a second III-V compound semiconductor layer for forming the first semiconductor optical element on the first III-V compound semiconductor layer; forming an etching mask on the first region after forming the second III-V compound semiconductor layer; forming the first semiconductor optical element by using the etching mask to dry-etch the second III-V compound semiconductor layer; and forming the second semiconductor optical element on the second region after forming the first semiconductor optical element, wherein, in the step of forming the first semiconductor optical element, an end point of dry etching is detected by performing dry etching while detecting the Al element.