PURPOSE: To prevent the production of roughness of an electrode mirror surface due to heat treatment by isolating a reflection mirror surface from an electrode.
CONSTITUTION: A disc mirror surface region 7c at the center of a ring-formed junction region 7b contacts P-InP layer 5 via an insulation layer 6. When a drive current flows into the electrode 8 from its ring-formed junction region 7b, an active region 10 is formed in a CaInAsP layer 4 by a stricture current. But, a Fabry-Perot resonator is formed between the disc mirror surface region 7c at the center of the ring-formed junction region 7b and the mirror surface of a Au film 9, and accordingly a laser oscillation 11 generates there. The light by this laser oscillation is emitted to the vertical direction as shown by the arrow 12 in the same manner as convention. Since the disc mirror surface region 7c of Au/Zn is isolated from the P-InP layer 5 by the insulation layer 6 of SiO2, etc., the fusion of Au/Zn with In generated at the ring-formed junction region at the time of annealing treatment is prevented by the SiO2 layer on the mirror surface 7c, and accordingly an excellent state of mirror surface of high reflectance can be maintained.
SOUDA HARUHISA
TERAKADO TOMOJI
