Patent ID: 8472495

Claim:
A laser device having first and second opposed end faces, the laser device comprising: a substrate; a laminated semiconductor structure on said substrate, said laminated semiconductor structure comprising a plurality of semiconductor layers including a lower cladding layer, an active layer having a first disordered portion spaced from said first end face of said laser device and first and second non-disordered portions adjacent and sandwiching said first disordered portion, and an upper cladding layer located on said active layer; and a diffraction grating located in a portion of a layer of said laminated semiconductor structure, above or below said active layer, with respect to said substrate, said diffraction grating defining a diffraction grating section of said laser device, wherein said laser device includes a bulk section, free of any diffraction grating, adjacent said diffraction grating section at a boundary, said laser device includes a disordering impurity region, including a disordering impurity, extending through parts of said upper cladding layer, said active layer, and said lower cladding layer, and said disordering impurity region contains said first disordered portion of said active layer and the boundary between said diffraction grating section and said bulk section.