摘要 |
Disclosed is an improved method for forming corrosion resistant beam lead connectors on semiconductor devices such as integrated circuits. A barrier layer of a titanium and tungsten alloy is deposited over the surface of the integrated circuit. A layer of gold is then deposited over the barrier layer. The layer of gold is patterned to define interconnection paths between the various devices of the integrated circuit and beam lead connection geometries, using photoresist and a gold etchant. The titanium-tungsten barrier layer is left intact during this step. The photoresist pattern is removed and a second pattern is applied to cover all areas of the integrated circuit except those areas where beam leads are desired. An additional layer of gold is plated to the appropriate thickness to form the beam leads, the photoresist pattern effecting a plating stop-off and the titanium-tungsten layer providing electrical continuity across the slice. Electrical separation between beam lead connectors and device interconnection paths is effected by etching the titanium-tungsten alloy with an etchant that attacks only the alloy, leaving the gold geometries intact.
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