| 摘要 |
PURPOSE:To obtain an integrated-type semiconductor laser, for high-output use, where laser beams excited from each active region are coupled at a low threshold value, at high efficiency and easily by a method wherein a current- blocking layer is constructed by three layers composed of respective specific AlGaAs so that SBA lasers can be integrated. CONSTITUTION:A first AlyGa1-yAs clad layer 2 of a first conductivity type is formed on a compound semiconductor substrate 1 of the first conductivity type; three layers consisting of an AlzGa1-zAs current-blocking and light- confining layer 3 of a second conductivity type, an AlalphaGa1-alphaAs light-guide layer 4 of the second conductivity type and an AlbetaGa1-betaAs current-blocking and light-confining layer 5 are formed on the first clad layer 2. Then, more than one stripe-like groove 12 whose cross section is shaped to be an inverted trapezoid is formed on the three layers 3-5; on the three layers 3-5 and on the stripe-like grooves 12 the following are formed in succession: a second AlyGa1-yAs clad layer 6; an AlxGa1-xAs active layer 7 which is situated in such a way that the distance to the substrate face inside the stripe-like grooves 12 is almost the same as that to the AlalphaGa1-alphaAs light-guide layer 4; an AlgammaGa1-gammaAs clad layer 8 of the second conductivity type. |
