| 摘要 |
1,178,180. Coated semi-conductors. WESTERN ELECTRIC CO. Inc. 21 March, 1967 [8 April, 1966], No. 13095/67. Heading H1K. Silicon nitride, alumina, or aluminum silicate is deposited to form a layer on the surface of a semi-conductor substrate, for example on to a silicon body or on to a silicon oxide layer on such a body. The deposited layer is shaped by covering it with a masking layer of silicon oxide, molybdenum, or platinum and etching with a hot phosphoric acid solution. The masking layer itself may be formed from a uniform layer by using conventional photoresist techniques in conjunction with etchants such as buffered hydrofluoric acid (for silicon oxide), nitric acid (for molybdenum), or aqua regia (for platinum). Silicon nitride may be deposited on to a heated substrate from a gas mixture of silane, ammonia, and hydrogen. Alumina may be deposited by mixing a stream of hydrogen/aluminum chloride with one of carbon dioxide, silicon oxide by mixing a stream of hydrogen/silicon tetrachloride with one of carbon dioxide, and aluminum silicate by mixing all these components. |
