Patent ID: 6768760
Filing Date: 2004-07-27
Classification: H01S

Abstract:
A ridge-waveguide semiconductor laser device comprising:a p-type semiconductor substrate; a p-type cladding layer formed on the p-type semiconductor substrate; a quantum well active layer formed on the p-type cladding layer; an n-type first cladding layer on the quantum well active layer; an n-type second cladding layer on the first cladding layer, being thicker than and of a different semiconductor materials from the n-type first cladding layer; and two trenches in the n-type second cladding layer, defining a ridge-waveguide between the two trenches; wherein each of the trenches reaches at least proximate the surface of the n-type first cladding layer and the n-type first cladding layer includes high-resistance regions, within portions of the n-type first cladding layer, directly opposite the trenches, the high-resistance regions having an higher resistivity than other regions of the n-type first cladding layer.