| 摘要 |
PURPOSE:To control active region width in excellent accuracy by a mechanism wherein a mask is formed on a surface of a semiconductor substrate, the surface thereof has a surface vertical to a cleavage surface, etched by an alcohol solution containing halogen, and worked so as to form inverse-mesa structure. CONSTITUTION:An active layer 2 is formed on a semiconductor substrate 1, a surface thereof has a {100} surface vertical to a {110} surface of a cleavage surface of InP crystals, and a clad layer 3 is made up on the layer 2. A cap layer 4 is built up on the layer 3, an oxide film is coated on the cap layer 4 by means of a CVD method, a stripe layer 7 is formed, and the layers are etched up to the substrate 1 by a bromine-methanol mixed solution using the stripe layer 7 as a mask, thus forming a mesa section. A buried region 5 is made up on the substrate 1 exposed by the etching, a buried region 6 is built up on the region 5, and the oxide film 7 is formed on the whole surface of the buried region 6 and the cap layer 4. |
