| 摘要 |
787,573. Semi-conductor devices. MULLARD RADIO VALVE CO., Ltd. Jan. 4, 1955 [Oct. 7, 1953], No. 27540/53. Class 37. A PN junction for a diode or transistor is produced by evaporating P-type semi-conductor material on to a N-type single crystal of the same basic material, to form a polycrystalline layer. The semi-conductor material may consist of germanium or silicon. A tantalum, molybdenum or pure carbon boat may be used to hold P-type germanium for evaporation, or a silica boat to hold P-type silicon. The surface of the N-type single crystal upon which deposition takes place, may be heated to 200- 400 ‹ C. by means of a winding on a copper slug. The process may be applied to both sides of the crystal to provide a PNP transistor. Specification 692,250 is referred to. Reference has been directed by the Comptroller to Specification 757,805. |
