| 摘要 |
901,064. Semi-conductor devices. BUSH & RANK CINTEL Ltd. Oct. 10, 1960 [Oct. 9, 1959], No. 34262/59. Class 37. During the manufacture of a semi-conductive element powdered cadmium sulphide including as significant impurities indium and copper, the concentrations of each of which is 1 to 10,000 of cadmium sulphide is formed into a tablet and heated in sulphur vapour to render it photo-sensitive. In the particular -process described 1.15 milligrams of indium sulphide are mixed with 8 grams of cadmium sulphide and ground until grain size is of the order of 10 Á. The powder is made into a paste with 1 millilitre of a solution formed by dissolving 32 milligrams of copper sulphate in 10 millilitres of distilled water. The paste is then dried in air in an oven raised to 130‹ C. and then moulded into tablet form. The tablets 13 are loaded into one end of a split quartz tube 14 shown in Fig. 2. Next, 0.25 grams of sulphur 13 are placed in the other end and the two parts sealed at 17. The tube is outgassed at 18 and sealed off and then heated to produce a sulphur vapour pressure of 4 atmospheres and is placed in an oven where the sulphur is maintained at 500‹ C. and the tablets at 900‹ C. The quartz tube is quenched in water and the tablets removed and heated on a mica sheet at 25‹ C. per minute to 375‹ C. The mica sheet is placed on a metal block which cools the tablets in 5 seconds. Conductive material is applied to form the electrodes, the material described in Specification 888,907 being suitable. The heating to 375‹ C. and cooling are repeated until the sensitivity is correct. The tablets are provided with metal clips 22, 23 which engage the surface electrodes 24, 25 and with connecting wires 26, 27. The tablet with connections is placed in a recess in a transparent block of polystyrene. The recess is enlarged at 34 to take a sealing compound of unset resin loaded with glass frit or powdered mica after flushing the cavity with argon. The device may also be encapsulated in the block with an epoxy resin. Specification 861,048 also is referred to.
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