SEMICONDUCTOR LASER DEVICE AND ITS MANUFACTURING METHOD

摘要

A semiconductor laser device has a semiconductor layer formed over a substrate and including an active layer interposed between an n−type layer and a p−type layer. The semiconductor layer has a resonator face formed by etching and a projection projecting from the resonator face in the direction of the emission of the laser beam. A protective film is so formed as to extend from the resonator face to the end face of the projection. The semiconductor laser device is characterized in that the emission half−angle of the emission distribution in the vertical direction of the laser beam emitted from the resonator face is larger than the emission critical angle.