| 摘要 |
1,192,144. Semi-conductor devices. HITACHI Ltd. 1 Oct., 1968 [2 Oct., 1967], No. 46532/68. Heading H1K. An insulating coating on the surface of a semi-conductor substrate comprises a silicon nitride film and an inorganic insulating layer containing silicon oxide and phosphorus oxide formed on the surface of the silicon nitride film. The silicon nitride film may be directly in contact with the semi-conductor substrate or may be separated therefrom by a layer, e.g. of silicon dioxide. Preferably a silicon substrate is exposed to an atmosphere containing nitrogen, ammonia and monosilane at an elevated temperature (875‹ C.) to form the silicon nitride film and then exposed to an atmosphere of oxygen and phosphorus oxychloride (POCl 3 ) at between 800‹ and 1200‹ C., preferably between 1000‹ and 1100‹ C., to form the silicon oxide-phosphorus oxide layer. The invention may be applied to a Metal- Insulator-Semi-conductor diode comprising an N-type silicon substrate and gold and aluminium electrodes, the aluminium electrode being separated from the substrate by the silicon nitride and silicon oxide-phosphorus oxide layers. A plurality of diodes is made on a silicon substrate which is subsequently divided to form the individual diodes. It is stated that the provision of the insulating layer of the invention improves the stability of the capacitance-voltage characteristics. Other applications described include a planar junction transistor having diffused emitter and base regions and an insulated-gate field-effect transistor. In both cases, selected portions of the insulating layers are removed by etching first with hydrofluoric acid and then with phosphoric acid to permit the introduction of the electrodes to the appropriate regions of the semi-conductor devices. A plurality of fieldeffect transistors may be formed in a single substrate and interconnected by metal layers applied over the surface of the insulating layers. |
