| 摘要 |
A process for electroforming a bump circuit and a lead circuit on a tape to be used for making contact with integrated circuit chips and the like. By means of the process, an inverse bump pattern is produced. To this end, a first metal plate is coated with a photoresist on one surface and suitable apertures are made in the photoresist in a conventional manner. Now indentations are chemically etched, partly through the uncovered metal surface to form a bump circuit. Next the photoresist is completely removed and the metal plate is again covered with a layer of photoresist. After the photoresist is developed again to form a lead circuit, the metal is chemically etched partly through the uncovered metal to form a lead circuit while at the same time further etching the bump circuit indentations. These indentations are now covered with metal by various plating steps. For example, the indentations may be covered successively with layers of gold, nickel, copper, and an additional layer of gold. The original metal is then removed by chemical etching. Either the remaining photoresist may remain or else the remaining photoresist is completely removed and a new layer of photoresist is applied over the entire structure before the original metal is removed by chemical etching. The final product is an electroformed lead and bump circuit on a tape to provide a flexible carrier.
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