Patent ID: 6741630
Filing Date: 2004-05-25
Classification: H01S

Abstract:
A ridge waveguide distributed feedback laser comprising:an n-type semiconductor substrate on which a plurality of semiconductor layers are sequentially arranged, including an n-type cladding layer, an active layer, and a p-type cladding layer; a ridge waveguide disposed on the p-type cladding layer, the ridge waveguide including p-type first and second InP layers sandwiching a p-type InGaAsP grating layer, the second p-type InP layer being more remote from the p-type cladding layer than the first p-type InP layer and containing zinc, the p-type InGaAsP grating layer having a carrier density ranging from 1.5Ã—1018 cmâˆ’3 to 4.0Ã—1018 cmâˆ’3 for retarding diffusion of zinc from the second p-type InP layer into the p-type InGaAsP grating layer; and first and second electrodes respectively in electrical communication with the substrate and the ridge waveguide.