| 摘要 |
PROBLEM TO BE SOLVED: To reduce the threshold value of a semiconductor laser, to raise the reliability of the laser by providing a layer on a GaAs substrate for adding at least either of phosphorus and nitrogen to a specified compound so that the GaAs substrate and a lattice constant agree with each other. SOLUTION: A blocking layer 115 is etched off in a stripe shape and a P-type Ga1-uAluAs1-vPv clad layer 116, a P-type Ga1-uAluAs1-vPv intermediate composition layer 117, and a P-type GaAs contact layer 118 are formed. A P-side electrode 119 is formed on the layer 118 and an N-side electrode 120 is formed on the rear of a substrate 111. In order to lattice-match the layer 116 to the GaAs substrate 111, the composition (v) of P is selected so as to satisfy v=0.0090u/(0.2020+0.0092u) to the component (u) of aluminium. Thereby, the generation of a lattice strain in the substrate is dissolved, a stress in an active layer 113 is significantly reduced to improve the initial characteristics, such as the luminous efficient, of an element and at the same time, the long-run reliability of the element can be also improved. |
