Patent ID: 7037743

Claim:
A method for producing a semiconductor laser device comprising the steps of: forming a semiconductor multilayer structure on a semiconductor substrate of a first conductivity type, the semiconductor multilayer structure including: a cladding layer of the first conductivity type; an active layer having a super-lattice structure; a first cladding layer of a second conductivity type; an etching stop layer of the second conductivity type; a second cladding layer of the second conductivity type; a band graded layer of the second conductivity type; and an impurity supply control layer; disordering the active layer by diffusing an impurity at least through the impurity supply control layer at least in a predetermined region within the semiconductor multilayer structure; and patterning the second cladding layer into a ridge structure by wet etching, wherein a concentration of the impurity diffused in the etching stop layer within the predetermined region is greater than a concentration of the impurity outside the predetermined region and equal to or smaller than about 2×10 18 cm −3 .