| 摘要 |
1,225,105. Coating with Rare Earth Alloys. INTERNATIONAL BUSINESS MACHINES CORP. Aug. 27, 1969 [Sept. 19, 1968], No. 42563/69. Headings C7A and C7F. [Also in Division H1] An alloy contact is provided on a rare-earth semi-conductor body by depositing the alloy on the semi-conductor body, heating the alloy and the body in an inert atmosphere to the melting point of the alloy to cause the alloy to melt, and continuing the heating to cause the alloy to partially diffuse into the body, the alloy comprising a rare earth metal such as cerium, praseodymium, neodymium, lanthanum, gadolinium, terbium, dysprosium, halmium, erbium, thulium, ytterbium or lutetium, and a metal of good electrical conductivity such as gold, silver, copper, zinc, nickel, cobalt, palladium or platinum. In one embodiment a mixture of powdered lanthanum and silver is placed in a crucible in an inductively heated furnace in an argon atmosphere and fused to form an eutectic alloy. In a second embodiment rods of lanthanum are placed with gold foil on the hearth plate of a conventional D.C. furnace and the arc struck to form an ingot of alloy which is inverted and remelted at least three times to ensure homogeneity. A table of various alloy compositions is given. The semi-conductor material is an alloy of the equation Eu x RE 1- x A where Eu is the rare earth europium, RE is a rare earth element, A is a chalcogen and 0<x< 1. |
