| 摘要 |
PROBLEM TO BE SOLVED: To obtain a semiconductor laser having in which self-excited oscillation is effected well by having increasing the dopant concentration of a p-type saturable absorption layer in an AlGaInP based semiconductor laser. SOLUTION: A saturable absorption layer 7 comprises not a GaInP based semiconductor layer, but an AlGaAs based semiconductor layer and it is doped heavily with C. Consequently, the AlGaAs based semiconductor layer can be doped with C at a concentration higher than the GaInP based semiconductor layer being doped with Zn. Since the diffusion of C in the AlGaAs based semiconductor layer is significantly low as compared with diffusion of Zn in the GaInP based semiconductor layer, high concentration doping causes no deterioration of laser characteristics due to diffusion of dopant into an active layer 4. |
