Patent ID: 6618420
Filing Date: 2003-09-09
Classification: H01S

Abstract:
A semiconductor laser unit comprising:a substrate; a first laser emitting a light of a first wavelength, disposed on said substrate, having: a bulk active layer having a thickness larger than the quantum-mechanical-maximum thickness, configured such that electrons in the bulk active layer can be treated by classical theories, but not larger than 0.1 &mgr;m, the quantum-mechanical-maximum thickness being so defined that only under the maximum thickness the electrons are allowed to be treated by quantum-mechanical analysis; a first cladding layer of a first conductivity type, directly contacting a lower portion of said bulk active layer; a first cladding layer of a second conductivity type opposite to the first conductivity type directly contacting an upper portion of said bulk active layer; and a second laser disposed on said substrate and isolated from said first laser, having a multi quantum well active layer in which the electrons are treated by the quantum-mechanical analysis, comprising a plurality of potential well structure composed of a quantum well layer and barrier layer adjacent to the quantum well layer, the second laser emitting a light of a second wavelength different from said first wavelength.