Patent ID: 7830937

Claim:
A surface emitting type optical semiconductor device comprising: a substrate; a first reflecting mirror layer provided on the substrate and having a first semiconductor multilayer film; a semiconductor active layer provided above the first reflecting mirror and having a light emitting region; a second reflecting mirror layer provided above the semiconductor active layer and having a second semiconductor multilayer film, the first and second reflecting mirror layers forming an optical cavity in a direction perpendicular to the substrate; a plurality of current confinement regions provided in the second reflecting mirror layer so as to be separated by an impurity region having impurities, each of the current confinement regions having a current confining path; a semiconductor current diffusion layer provided on the second reflecting mirror layer so as to cover the current confinement regions; and an electrode portion which injects a current into the semiconductor active layer, the electrode portion comprising a first electrode provided on the semiconductor current diffusion layer so as to surround the current confinement regions and a second electrode provided on an opposite side of the substrate from the semiconductor active layer, wherein the semiconductor current diffusion layer has a stacked structure of a plurality of semiconductor current diffusion films, and the current diffusion film located nearer the semiconductor active layer is formed so as to have higher resistance in a peripheral part located far from a center of the region surrounding the current confinement regions as compared with a central part located near the center of the region surrounding the current confinement regions and so as to have higher resistance in the peripheral part as compared with the semiconductor current diffusion film located farther from the semiconductor active layer.