摘要 |
The junctions of a plurality of semiconductor devices are formed in a common wafer. The upper surface of the common wafer is metallized for each of the individual devices by a nickel, chromium, nickel, silver metallizing system. Individual wafer elements are thereafter separated from the main wafer and their bottom surfaces are vacuum-alloyed to a molybdenum expansion plate. Thereafter, the outer periphery of the devices is tapered by grinding and the periphery is etched by hot potassium hydroxide without need to protect the upper metallizing from the etch. The caustic etch is washed with citric acid. Thereafter, the periphery is passivated by a passivation coating.
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