| 摘要 |
PROBLEM TO BE SOLVED: To provide a multi-wavelength semiconductor laser that eliminates the need for high-precision mechanical mounting for aligning optical axes of individual LDs emitting laser light beams differing in wavelength.SOLUTION: On a part of a substrate 10 made of n-type GaAs, a composition modulation buffer layer 20 made of n-type GaAsN(0≤x≤1) mixed crystal is formed. On the composition modulation buffer layer 20, first semiconductor layer 40 is formed which includes an active layer made of a nitride semiconductor. A second semiconductor layer 50 which includes an active layer made of AlGaAs is formed on the substrate 10 so as to be arranged in parallel with the composition modulation buffer layer 20. A third semiconductor layer 60 which includes an active layer made of AlGaInP or GaInP is formed on the substrate 10 so as to be arranged in parallel with the second semiconductor layer 50. The composition modulation buffer layer 20 is formed having an inclined composition increasing in N atom content from the substrate 10 toward the first semiconductor layer 40. |
