| 摘要 |
PROBLEM TO BE SOLVED: To actualize a projection beam of good quality which can be oscillated continuously in basic lateral mode and has no astigmatism suitable for the light source of an optical disk system, etc. SOLUTION: The semiconductor laser is constituted by forming an n type GaAlN clad layer 13, an active layer 16 of MQW(multiquantum well), and a p type GaAlN clad layer 19 on an n type GaN buffer layer 11 on a sapphire substrate 10 and the clad layer 19 is equipped with a double heterostructure part with striped ridges and a light confinement layer formed in an area other than the ridge part of the clad layer 19 on the double heterostructure part. In this case, the refractive index of the light confinement layer is made larger than the refractive index of the p type GaAlN clad layer. Consequently, threshold current density is reduced by controlling a lateral mode by forming a waveguide structure with a refractive index distribution, and in the lateral mode, an InGaAlBN-based semiconductor laser can continuously be oscillated. |
