| 摘要 |
789,931. Semi-conductor materials. MULLARD RADIO VALVE CO., Ltd. April 25, 1956, No. 12697/56. Class 37. An electrode is formed on a semi-conductor by heating the semi-conductor and a wire held thereon in a jig to a temperature above the eutectic point of the alloy of the semi-conductor and the wire but below their individual melting-points so that, on cooling, an alloy containing the semi-conductor in excess of the eutectic proportion solidifies first. As shown, Fig. 1, through a vertical aperture 3 in a carbon jig 1 placed on the surface of a slice of N-type monocrystalline germanium 2, is disposed a gold wire 4 whose lower end touches the germanium 2. When the arrangement is heated to between 356‹ and 936‹ C. the gold 4 alloys with the surface germanium, moving downwards until stopped by the engagement of a bent-over portion 5 on the jig 1, when the alloy electrode 6 (Fig. 2) detaches itself from the wire 4 and the heating is stopped. On cooling, gold-saturated germanium recrystallizes on the undissolved N-type germanium forming a P-N junction, further solidification presumably being of the gold-germanium eutectic. A connecting wire is soldered to the electrode 6 and a connection is provided to crystal 2, which is etched, e.g. in hydrogen peroxide. |
