Semiconductor laser device and method of fabricating the same

Abstract

A monolithic two-wavelength semiconductor laser device includes a front end face film 19 on a resonator front end face 18, and a high-reflectivity end face film 22 as a multilayered film on a resonator rear end face 21. The front end face film 19 is formed using a low-refractive-index material, and the film thickness is so set that the reflectivity is 20%. The high-reflectivity end face film 22 is formed by alternately stacking thin films of low- and high-refractive-index materials, and the film thickness is so set that the reflectivity is 80%. The film thickness of each of these two end face films is calculated by an optical length d=(¼+j)×λm by using a mean value λm=(λ1+λ2)/2 of the oscillation wavelengths of the two semiconductor laser diodes. This makes it possible to obtain an end face film having a desired reflectivity and capable of being formed at once, and to fabricate a two-wavelength semiconductor laser device having high reliability, meeting the required performance, and also having high productivity.

Dependencies are inferred from the claim text.