Semiconductor laser with improved oscillation wavelength reproducibility

Abstract

A lateral mode control type of semiconductor laser has a high-yield structure having a long life and improved oscillation wavelength reproducibility. A diffusion limit layer formed of an undoped Ga.sub.0.5 In.sub.0.5 P layer and an undoped (Al.sub.0.6 Ga.sub.0.4).sub.0.5 In.sub.0.5 P layer is provided between a p-(Al.sub.0.6 Ga.sub.0.4).sub.0.5 In.sub.0.5 P clad layer and an undoped Ga.sub.0.5 In.sub.0.5 P active layer. The diffusion limit layer has a diffusion coefficient smaller than that of the clad layer. Impurity Zn diffused from the p-(Al.sub.0.6 Ga.sub.0.4).sub.0.5 In.sub.0.5 P clad layer during crystal growth or working is trapped in the undoped Ga.sub.0.5 In.sub.0.5 P layer almost entirely. A part of the impurity Zn diffuses in the undoped (Al.sub.0.6 Ga.sub.0.4).sub.0.5 In.sub.0.5 P layer thereunder but does not reach the undoped Ga.sub.0.5 In.sub.0.5 P active layer.

Dependencies are inferred from the claim text.