JPS6468995A - Semiconductor laser device and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a semiconductor laser device which has a large output without making an active layer thinner by a method wherein an n-type GaAs substrate is made to be doped with a p-type impurity and its surface is subjected to etching. CONSTITUTION:When a bias is impressed between a p-type electrode 10 and an n-type electrode 11 so as to make the p-type electrode 10 positive, a current does not flow through a region where a current blocking layer 7 is intervened, as the region is provided with a pnpn junction but a current flows through only a ridge section 8. But a current does not flow through a region even of the ridge section 8 where a p-type GaAs layer 2 is provided, as a pnpn junction composed of an n-type GaAs substrate 1, a p-type GaAs layer 2, a first clad layer 3, an active layer 4, and a second clad layer 5 is provided to the region. Therefore, the generation of heat due to a current does not take place at an end face. So, temperature of the end face does not rise, and even if a spot of laser rays is the same in size at the part where laser rays are guided, a COD level is made to be higher to enable laser rays to become larger in output.