| 摘要 |
PURPOSE:To prevent wire breaking on the Al layer, by forming selectively anodization film on the Al layer on the semiconductor wafer and by making the cross- section of the end part of the Al layer tapered when the films of that part are removed. CONSTITUTION:With resist mask on the Al layer 2 on the GaAs substrate 1, anodization is performed in the oxalic or sulphuric acid solution. The growth speed of the Al oxide film 5 thus anodized is so fast that its volume becomes greater than Al. Therefore the end part 4 of the mask 3 turns up forming Al pattern with cross-section of a very mild inclination. The Al anodization film 5 thus formed is removed in a solution which etches it faster than it etches Al2, and the mask 3 is taken off. No wire breaking take place when Ti-Pt-Au electrodes are stacked on the Al layer 3 with mildly tapered inclination thus obtained. Moreover, better coverage can be obtained when insulation film is formed. |
