With the excited light which radiation is done from the excitation light source and

摘要

PROBLEM TO BE SOLVED: To produce a low noise stabilized output by employing titanium as a material being arranged at the interface between a semiconductor layer and an electrode located closely to an active layer emitting light. ;SOLUTION: The semiconductor laser 2 is a refractive index waveguide type semiconductor laser having a wide oscillation region comprising an n-GaAs butter layer 22, an n-AlGaAs clad layer 23, an undoped active layer 24, and a partially mesa type p-AlGaAs clad layer 25 formed sequentially on an n-GaAs substrate 21. A p-GaAs cap layer 26 is formed on the upper surface of the mesa part and an insulation layer, i.e., an SiO₂ layer 27 is formed on the opposite sides the mesa part. Furthermore, a p-side electrode 28 of Ti/Pi/Au is arranged on the cap layer 26 and an n-side electrode 29 of AuGe/Ni/Au is arranged on the backside of the n-GaAs substrate 21. The p-side electrode 28 is formed by depositing Ti, Pt and Au sequentially from the side touching a semiconductor layer (cap layer 26).;COPYRIGHT: (C)1999,JPO