JPS6490579A - Manufacture of semiconductor laser device - Google Patents

Abstract

PURPOSE:To prevent the decomposition of a crystal in a current block layer by equalizing a crystal material exposed from the surface of a wafer both in the bottom of a grooved opening section and the surface of the current block layer. CONSTITUTION:When positive voltage is applied to an As side electrode 9 and negative one to an N side electrode 10, currents flow through a second clad layer 5, an active layer 4, a first clad layer 3, a buffer layer 2 and a substrate 1 through a contact layer 8a and a Zn diffusion region 7, to which a trench is formed through solid-phase diffusion from the bottom of an opening section 60. Holes from the second clad layer 5 having forbidden band width larger than the layer 4 and a refractive index smaller than the layer 4 and electrons from the first clad layer 3 are injected respectively to the active layer 4 having forbidden band width smaller than the layer 3 and a refractive index larger than the layer 3, and emission by the recombination of electrons and holes is generated. Consequently, stimulated emission starts when a current level is increased sufficiently, and reaches to laser oscillation. That is, not only a transition layer by the changeover of a gas is not formed in a current path but also the surface of the first conductivity type current block layer 6 is not brought to an irregular state, thus stably acquiring a current constriction effect and excellent laser characteristics.