JPS5635484A - Semiconductor laser - Google Patents

Abstract

PURPOSE:To obtain a stable basic mode oscillation by forming the one side central part of a light and carrier enclosing layer in streak-like recessed cup shape, burying it in a light guide layer, selectively superimposing an active layer thereon and burying the periphery with an epitaxial layer. CONSTITUTION:An N type Al0.1Ga0.9As light guide layer 13 of a groove 19 part formed on an N type GaAs layer 11 makes contact with an N type Al0.3Ga0.7 As light enclosing layer 12 bent toward the substrate 11 side, a GaAs active layer 14 exists only in a part of a flat projected guide layer, and the periphery is surrounded by a P type Al0.3Ga0.7As layer 15 and an N type A0.3Ga0.7As buried layer 16 of a light and carrier enclosing layer 15 on the periphery thereof. Since the lateral refractive index of the layer 13 becomes larger at the center than the outside, light is enclosed, and a stable basic mode can be oscillated. Inasmuch as the active layer is surrounded by the buried layer 16, most of the injected carrier can be contributed to the oscillation, the oscillation threshold can be reduced, and differentiated quantum efficiency can be increased, and a high power can be obtained.