摘要 |
1,193,373. Semi-conductor devices. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 23 Jan., 1968 [26 Jan., 1967], No. 3516/68. Heading H1K. [Also in Division C7] Electrical contact to an electronic device such as a diode, transistor, or integrated circuit is made by evaporating a layer of aluminium on to the surface of the device, by forming a layer of elementary nickel on at least parts of the aluminium layer (by evaporation, by atomizing techniques, or by vapour deposition), and by electrodepositing metal on to at least part of the nickel layer. In the embodiment, aluminium is deposited over a silicon oxide or silicon oxide-boron oxide film, aluminium is etched away except from the vicinity of holes exposing the emitter and base region of a transistor, and the remaining aluminium is alloyed into the semi-conductor. An overall coating of aluminium is then applied followed by an overall evaporated nickel coating (obtained by passing a heating current through a nickel filament). The nickel layer is selectively etched to form a desired contact pattern and copper then electroplated on to selected parts of the nickel pattern to form raised areas for flip-chip bonding. The structure is completed by etching away that part of the aluminium layer which is not covered by nickel. Etchant compositions are disclosed for selective removal of one or both of aluminium and nickel from silicon oxide. |