Patent ID: 8741670
Filing Date: 2014-06-03
Classification: B82Y,H01L,H01S

Abstract:
1. A method for producing an integrated optical device, comprising the steps of: preparing a substrate including a main surface including first and second regions arranged in a predetermined direction; growing, on the first and second regions of the substrate, a first stacked semiconductor layer including a first optical waveguiding layer, a first cladding layer positioned on the first optical waveguiding layer, and a side-etching layer positioned on the first cladding layer, the side-etching layer having a composition different from a composition of the first cladding layer; etching the first stacked semiconductor layer through a first etching mask formed on the first region until the first optical waveguiding layer is exposed; selectively growing, on the second region through the first etching mask, a second stacked semiconductor layer including a second optical waveguiding layer coupled to the first optical waveguiding layer and a second cladding layer positioned on the second optical waveguiding layer; and forming a reverse-mesa ridge structure by etching the first and second cladding layers through a second etching mask formed on the first and second stacked semiconductor layers, the second etching mask longitudinally extending in the predetermined direction, wherein the step of etching the first stacked semiconductor layer includes a step of forming an overhang between the first etching mask and the first cladding layer by selectively etching the side-etching layer by wet etching with an etchant having a higher etching rate for the side-etching layer than for the first cladding layer, and in the step of selectively growing the second stacked semiconductor layer, the second cladding layer is grown at a growth temperature lower than a growth temperature of the second optical waveguiding layer and a V/III ratio higher than a V/III ratio in the growth of the second optical waveguiding layer.