| 摘要 |
PURPOSE:To realize a longitudinal single mode which is stable in wave length by covering the end face to emit the light with amorphous material, and making the thickness enough larger than the wave length of the light in the material, and being near the refractive index of the material to the refraction of a semiconductor. CONSTITUTION:A diffraction grating 2 in which only the central member is shifted for phase is formed on an n-type InP substrate 1, and thereon a light guide layer 3, an active layer 4, a clad layer 5, a cap layer are grown in order by a liquid phase growth method. Hereafter, these grown layers are removed partially by chemical etching, and amorphous Si7 containing hydrogen is attached by CVD. Next, a p side electrode 8 and an n side electrode 9 are deposited and the element is cut off. Hereafter, an SiN film 10 is formed at the end face on the left by sputtering so as to reduce the reflection factor. For the thickness of amorphous Si, it is more than 2mum at least, desirably more than 4mum. Hereby, the low reflection factor end face excellent in reproducibility can be realized without recourse to crystal growth. |
