| 摘要 |
PURPOSE:To suppress a laser oscillation by increasing a gain with a carrier shut in and decreasing a gain at a part excluding recessed parts by a method wherein a large substance is buried in a band gap on a substrate having the band-shaped recess. CONSTITUTION:The band-shaped recess is formed on the N type GaAs substrate 1, a GaAlAs layer 2 having the band gap Eg1 being buried in the recess and then, a GaAlAs layer 3 having the band gap Eg2, a GaAlAs layer or GaAs layer 4 having the band gap Eg3, a GaAlAs layer 5 having the band gap Eg4 and a GaAs layer 6 having the band gap Eg0 are laminated in sequence over the whole surface. Then, electrodes 8, 9 are formed after oxide stripes 7 are formed so as to permit only the substrate recess to be conductive |
