| 摘要 |
PURPOSE:To make it possible to form, with excellent yield, a semiconductor laser which is free from optical damage, of large output, of low threshold value and of high efficiency, by making an active layer absorbing oscillation light not present in the vicinity of a reflection end surface, and introducing a layer of low Al composition at the time of buried growth in a window region. CONSTITUTION:An n-type clad layer 2, n-type light waveguide layer 3, active layer 4, p-type intermediate layers 5 and 6, p-type clad layer 7 and p-type electrode layer 8 are formed in order on an n-type sbstrate 1 by epitaxial growth. Mesa etching is performed in the form of an inverse mesa leaving a light emitting part only, and the width of a window region is made narrower than the light emitting part. An intermediate layer 5 and the active layer in the window region, and the active layer in a construction part 14 are eliminated by etching, and an n-type buried layer 9 and a p-type buried layer 10 are formed. Thus, an n-p inverse bias junction is formed in the vicinity of a p-n forward direction bias junction in the light emitting part, and current constriction is enabled. In the window region, the light waveguide layer 3 is surrounded by the layers of low refraction index, 9 and 10, and the n-type clad layer 2, and so acts as an excellent light waveguide mechanism. At the time of forming the layer 10, the p-type layer 6 of low Al composition is exposed, and then it is easy to bury the layer 10 by making the super-saturation degree of a solution high, because an oxidation scarcely ever occurs.
|
