Ridge guide distributed feedback laser and method of making same

Abstract From the Canadian patent

A distributed feedback laser which generates light of a specific wavelength comprises a body of semiconductor material having a cavity region positioned between first and second cladding layers of opposite conductivity. The cavity region is a ridge which extends in the longitudinal direction. The cavity region periodically varies in thickness in the longitudinal direction which is in the form of corrugations in a major surface thereof. The second cladding layer overlies the cavity region and the first cladding layer. This laser is fabricated by forming a first cladding layer overlying a substrate. A cavity layer is then formed over the first, cladding layer and corrugations are formed in a …