Patent ID: 7595508
Filing Date: 2009-09-29
Classification: B82Y,H01L,H01S

Abstract:
1. An optical semiconductor device comprising: a first clad layer of a first conduction type; an active layer fanned over the first clad layer, including a plurality of quantum dot stacks each of which is formed of a plurality of quantum dot layers and a plurality of first barrier layers alternately stacked, and a plurality of second barrier layers thicker than the first barrier layers stacked alternately with the quantum dot stacks; and a second clad layer of a second conduction-type formed over the active layer, the quantum clot layer being lattice mismatched with the first barrier layer, a film thickness of the first barrier layer being above a film thickness required to prevent an interaction between the quantum dot layers, a film thickness of the second barrier layer being above a film thickness required to mitigate a lattice strain due to a lattice mismatching between the first barrier layer and the quantum dot layer, all of the quantum dot layers of all of the plurality of quantum dot sacks having the same composition.