| 摘要 |
PURPOSE:To provide a semiconductor laser device, which can be manufactured easily and from which low noises are generated. CONSTITUTION:An alumina film 1a having a refractive index lower than a substrate crystal and a silicon film 1b having a refractive index higher than alumina are laminated and formed on the ray outgoing section 3 of the ray outgoing side end face of a semiconductor substrate 4 and other regions except a section in the vicinity of the ray outgoing section 3. An alumina film 1c is further arranged selectively on at least the ray outgoing section 3. The film thickness of the alumina film 1a and the silicon film 1b is set so that refractive indices to laser beams reach 3% or less. When the alumina film 1a and the silicon film 1b are controlled within a range of approximately + or -1nm to specified film thickness, yield differs from the time when the film thickness of the dielectric film of a single layer is controlled, and high yield is acquired, and the generation of noises due to re-incidence to an optical pickup of the reflected rays of returned rays on a crystal surface can be inhibited. |
