| 摘要 |
PURPOSE:To obtain a semiconductor device having desired electrical and optical properties, by making the Miller indice deviation in the direction parallel to the ridge direction of an uneven part such as a stepped part and a groove in a crystal layer formed on a substrate, larger than that in the direction perpendicular to the ridge direction. CONSTITUTION:With a (100) plane employed as a substrate surface, a stepped part is formed on the surface of a substrate 12 so as to have an inverted mesa-shaped cross- section. It is assumed that the Miller indice deviation from the (100) plane in the ridge direction of the stepped part is theta2 and the Miller indice deviation from the (100) plane in the direction perpendicular to the ridge direction of the stepped part is theta1. A surface 10 has the stepped part, while a surface 11 has the Miller indice deviations theta1 and theta2. In a semiconductor laser element formed by providing, on a GaAs single crytal substrate 12 having a stepped part, an N type GaxAl1-xAs clad layer 17, a GayAl1-yAs active layer 18, a P type GaxAl1-xAs clad layer 19, an N type GaAs layer 20 and an N type GazAl1-zAs layer 21, for example, by selecting values of Miller indice deviations so as to satisfy the relationship, theta1<theta2, it is possible to improve the controllability and reproducibility of the semiconductor layer configuration as seen at a distance 22d. |
