Semiconductor device contact layers

Abstract

Abstract 1,177,414. Semi-conductor devices. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 14 Feb., 1967 [16 Feb., 1966], No. 6931/67. Heading H1K. [Also in Division C7] A contact layer for a semi-conductor device is made by depositing on a substrate a coherent metal layer with semi-conductor inclusions capable of alloying with the metal from a fluid containing semi-conductor particles in suspension at a temperature below that at which said alloying occurs. The substrate may be of tungsten, molybdenum, nickel, nickel-iron or nickel-iron-cobalt alloy, ceramics such as alumina, or a semi-conductor body. Where self supporting layers are required use is made of a temporary substrate, e.g. of stainless steel or metallized glass, from which the layer can be peeled. The layer metal may be aluminium, gold, silver, cobalt or nickel or combinations thereof while the particles may consist of one or more of germanium, silicon, and gallium arsenide. Deposition of the metal may be effected by electroplating or electroless deposition from specified solutions. In a typical example boron doped silicon particles are incorporated in gold deposited on a gold plated boron-diffused area of an oxide coated N-type silicon body while antimony doped particles are incorporated in a similar fashion in a coating on the opposite face of the body. The assembly is completed by heating to above the eutectic temperature of gold and silicon. In another embodiment a nickel header to which a silicon diode, transistor or integrated circuit element is to be attached is electroplated in a gold potassium cyanide bath containing in suspension silicon particles of less than 5 Á diameter. Alternatively the header is electroless plated with nickel from a bath containing silicon particles.

Inventors

• 👤 Rodolphe Lacal

Bibliographic Details