Abstract of the Disclosure

Epitaxial gallium arsenide bulk-effect diodes are made by the following process: an n-conductivity layer is grown on a slice of n⁺ gallium arsenide; an n⁺⁺ layer is grown on the n layer; a silver-germanium mixture, or other high temperature alloy or metal, is evaporated on the n⁺⁺ layer and alloyed at about 600 degrees centigrade; the alloy layer is covered with evaporated or electroplated gold or silver; the thickness of the n⁺ slice is reduced by chemical polishing; an indium-gold, or other lower temperature alloy, layer is evaporated on the n⁺ slice and alloyed at about 500 degrees centigrade; the indium-gold layer is electroplated with gold or silver; the entire structure is cut by etching into individual elements; and each element is bonded between opposite conductive studs.

• Figure 1 is a flow chart of a process for making epitaxial semiconductor devices in accordance with one embodiment of the invention.
• Figure 3 is a schematic illustration of part of the semiconductor structure of a partially fabricated semiconductor structure in accordance with the process of Figure 1.
• Figure 5 is a flow chart indicating steps of an alternative embodiment of the invention which differ from corresponding steps of the chart of Figure 1.

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