| 摘要 |
1,203,086. Semi-conductor devices. TEXAS INSTRUMENTS Inc. 15 Sept., 1967 [30 Dec., 1966], No. 42214/67. Heading H1K. [Also in Division C7] An electrical lead in ohmic contact with a region of an insulation coated semi-conductor body includes a gold layer overlying a layer of molybdenum, with a further layer of molybdenum on top of the gold layer. In constructing a typical silicon integrated circuit comprising a number of sub-circuits, only part of which is shown in Fig. 7, after formation of the device zone configurations by epitaxy and diffusion a surface oxide film is apertured by photoetching at desired contact points and successive layers of molybdenum, gold, molybdenum applied by sputtering, evaporation or sublimation. These are form-etched to provide the requisite first level of interconnections, which extend to contact pads at the periphery of each subcircuit section. After optionally heating in oxygen to form a genetic molybdenum oxide film on the interconnections the entire surface is coated with silicon nitride, silica, alumina, tantalum oxide or an organic insulant by evaporation or sputtering. This layer, together with the underlying molybdenum oxide and molybdenum is etched away over the contact pads and then further layers of molybdenum and gold deposited and form-etched to form a second layer of interconnections between the sub-circuits, and gold wires are thermocompression bonded to the terminal areas of this second layer. To improve the quality of the contacts to the silicon a thin film of aluminium or platinum silicide and/or a heavily doped diffused region may be provided at the molybdenum-silicon interface, and traces of platinum can be added to the gold to make it adhere more readily to the molybdenum. |
