| 摘要 |
PURPOSE:To enable to obtain a semiconductor laser element, whose threshold-value current is low and luminous efficiency is high, at a higher yield by a method wherein the optical waveguide region is made to coincide with the current region in a self- matching way. CONSTITUTION:An N type GaAs layer 9 with a flat surface is laminated on a P type GaAs layer 8, a quarangular cylinder-shaped diffusion source 10, wherein the cross section vertical to the long axis is trapezoidal and the lower bottom of the trapezoid is facing the side of the layer 8, is provided on the layer 9, and a substrate is constituted. A P type first clad layer 2, an active layer 1 and an N type second clad layer 3 are successively laminated on the substrate. In this constitution, when impurities are diffused in the range indicated by dotted lines from the diffusion source 10, only the part of the layer 9, where is included in the range, is turned into a P type and the other parts of the layer 9 remain to be an N type. Accordingly, in case bias voltage is impressed in the forward direction between the layer 8 and an electrode layer 13, current concentrates in the vicinity of the protruded tip face of the diffusion source 10 and only the part of the layer 1, where is opposed to the protruded tip face, becomes a luminous region. That is, the optical waveguide region and the current region are made to mutually coincide in a self-matching way. |
