| 摘要 |
886,291. Semi-conductor devices. PHILIPS ELECTRICAL INDUSTRIES Ltd. April 3, 1958 [April 5, 1957], No. 10856/58. Class 37. A semi - conductor device is mounted in a gas-tight envelope in an atmosphere comprising an amount of water vapour beneficial to the electrical properties of the device, the envelope also containing a store of water in a loosely bound state which is large compared with the amount involved in any reactions or adsorption within the envelope. The water store may be a hydrate, e.g. of potassium aluminium sulphate, barium chloride, zinc ammonium sulphate, potassium nickel sulphate, potassium cobalt sulphate or sodium bromide, which may be mixed with a filler such as sand, or with a binder such as a silicon vacuum grease or oil. If the store material is reactive with the semi-conductor material the latter is embedded in a binder and separated from the store by a porous wall, e.g. of glass wool or asbestos. Other suitable stores are a mixture of thallium oxide and hydroxide, a mixture of magnesium oxide and hydroxide, aqueous solutions of calcium chloride, manganese chloride, and phosphoric acid, and silica gel or silicon vacuum grease or oil containing absorbed water. In the embodiment a transistor 1 (Fig. 1) comprising indium emitter and collector electrodes alloyed to an N-type germanium wafer provided with a nickel base tab attached by a tin-antimony solder, is mounted in a two-part glass envelope 2, 3. Before the final assembly the cup-shaped part 3 of the envelope is filled with a mixture of a silicon vacuum grease and hydrated zinc ammonium sulphate. Vacuum sealed transistors embodying the above-mentioned water stores possess the highα-characteristic of a transistor mounted in humid air with the stability of a transistor which has been baked to remove moisture before sealing. |
