Patent ID: 9647425
Date: 2017-05-09
CPC Classifications: H01L,H01S

Claim:
1. A method of manufacturing an optical semiconductor device comprising: successively laying a first cladding layer, an active layer and a second cladding layer on a semiconductor substrate to form an optical semiconductor element; obtaining a refractive index of the active layer by a photoluminescence inspection and computing an equivalent refractive index of the optical semiconductor element; successively laying a third cladding layer, an optical waveguide layer jointed to the active layer and having a refractive index smaller than that of the active layer, and a refractive index adjustment layer on the semiconductor substrate to form an optical waveguide; obtaining a refractive index of the optical waveguide layer by a photoluminescence inspection and computing an equivalent refractive index of the optical waveguide; adjusting a film thickness of the refractive index adjustment layer by etching the refractive index adjustment layer so that the equivalent refractive index of the optical semiconductor element and the equivalent refractive index of the optical waveguide are matched to each other; and after adjusting the film thickness of the refractive index adjustment layer, forming a contact layer on the second cladding layer and the refractive index adjustment layer, wherein the optical waveguide is a passive waveguide to which no electrical field is applied and no current is injected.