| 摘要 |
PURPOSE:To improve characteristics and the yield of manufacture, by using a substrate having a groove along a portion to be a waveguide. CONSTITUTION:A groove 32 is provided on an N type GaAs substrate 11. At least two continuous semiconductor layers are made on the surface of the substrate 11 having the groove 32, thereby changing the groove into a flat surface. Both the semiconductor layers on the band groove 32 are then removed by mesa etching so that at least a part of the semiconductor layers is left. After both continuous semiconductor layers exposed to at least mesa-etched sides are covered with a new semiconductor layer, the substrate is cleft perpendicularly to the longitudinal direction of wide part 322 of the groove 32. |
