| 摘要 |
PURPOSE:To eliminate cavities generating in the filling insulator by making V-grooves as element-isolating grooves by a method wherein a resist adhered on a substrate is opened in taper form, and a V-groove is formed in the substrate by anisotropic etching with the resist as the mask. CONSTITUTION:A GaAs layer 2, a P-GaAs layer 3, an N-AlGaAs layer 4, and an N<+>-GaAs layer 5 are epitaxially grown on the GaAs substrate 1 of the title device; thereafter, the whole substrate is coated with a resist 9, and a V-groove 10 forming region is opened by the process of photolithography. At this time, the aperture edge of the resist 9 is tapered by selecting the conditions of exposure. Next, the V-groove 10 reaching the substrate 1 is formed by ion milling with the resist 9 as the mask. After removal of this resist 9, the whole substrate is coated with an insulation film 7 by chemical vapor phase growth by filling the V-groove 10. Further, the V-groove 10 coated with the film 7 is used as the element-isolating groove by etching the film 7 and the resist 11 coating thereon until the layer 5 is exposed. |
