| 摘要 |
Plates for use in semi-conductor devices (see Group XXXVI) are formed by sintering a mixture containing 80-99% by weight tungsten, 0-10% gold and 0.2-10% nickel, or a mixture of 70-99% molybdenum, 0-10% gold and 0.2-20% nickel. A typical plate consisting of 98 parts by weight tungsten, 1 part gold and 1 part nickel is formed by compressing together powders of the individual metals and sintering at 1400 DEG C. for an hour in hydrogen. Coatings of nickel, gold or silver may be formed on one face of the plate by applying nickel carbonyl powder or silver or gold powder in a binder at some stage before sintering. Alternatively the materials are applied after sintering and bonded to the plates by reheating in hydrogen. In an alternative method the mixture of metal powders is prepared by precipitating compounds of the metal from a common solution and reducing the powdered compounds to metal. |
