Patent ID: 6573116
Filing Date: 2003-06-03
Classification: H01S

Abstract:
A method of manufacturing a ridge type semiconductor laser of laterally-coupled distributed feedback having an active layer made of semiconductor; a cladding layer formed on said active layer; a ridge stripe formed to protrude from said cladding layer; and a grating having a periodic structure in the direction in which the ridge stripe extends and formed on the side walls of the ridge stripe and on flat portions on both sides thereof, comprising the steps of:forming a stripe mask having a predetermined width over a cladding layer made of a material for a ridge stripe formed on an active layer made of semiconductor formed on a laser substrate, to form two lateral flat portions from said cladding layer, by a selective wet etching, so as to form a ridge stripe protruding therefrom and having a flat top portion at which the stripe mask capped; forming a grating mask on said two lateral flat portions, side walls of said ridge stripe and said stripe mask, said grating mask having a periodic structure in the direction in which the ridge stripe extends; and dry-etching through said grating mask said two lateral flat portions and said side walls of the ridge stripe and then wet-etching said two lateral flat portions and said side walls of the ridge stripe to form a grating made of said material for the ridge stripe on said two lateral flat portions, said side walls of the ridge stripe and said active layer, so as to define a bracket grating portion adjacent to the ridge stripe.