Verfahren zur Herstellung von Halbleitervorrichtungen

摘要

1,225,277. Semi-conductor devices. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 11 March, 1968 [14 March, 1967], No. 11730/68. Heading H1K. In a method of manufacturing a semiconductor device of the kind in which granules of a semi-conductor compound are embedded in an insulating foil and are contacted by electrode layers, granules of a component of the compound are converted into granules of the compound by a chemical reaction and are then incorporated into the foil. The invention allows the production of uniform spherical granules of compounds which are either too hard or too soft to form into granules by grinding. Carbon granules formed by carbonizing pellets produced by spraying plastics material may be reacted with silicon to form silicon carbide granules. Silicon granules formed by spraying silicon in an argon plasma may be reacted with carbon to form silicon carbide granules. Granules of indium or cadmium formed by spraying molten metal in a viscous liquid, e.g. silicone oil, or of iron formed by spraying in an argon plasma may be reacted with phosphorus, sulphur or oxygen to form granules of the compound. In addition to the above methods of forming spherical granules of the starting component, rough granules produced by grinding may be heat treated, for example, in an arc plasma to round-off their surfaces. Acceptor or donor dopants may be incorporated in the compound either during or after the chemical reaction. Alternatively, the dopants may be incorporated in the granules of the starting component of the compound. The granules may be only partially reacted so that a surface layer of the compound is formed on a core of the component material. Such granules may be incorporated into an insulating film and then processed, e.g. by etching or grinding, to expose the cores of the granules on one side of the film. In an embodiment, granules of silicon carbide are incorporated in a foil, and the opposite faces are provided with ohmic and non-ohmic contacts by vapour depositing gold in a vacuum of 10-8 and 10-1 mm. of mercury respectively. Pieces of the foil may be used as voltage dependent resistors. In a second embodiment, granules of silicon carbide doped with aluminium are incorporated in a foil, and provided with ohmic contacts on both faces by vapour depositing gold alloy containing tantallum and aluminium. Pieces of the foil may be used as resistors with a negative temperature coefficient. Granules of silicon carbide containing phosphorus may be used to form resistors with a positive temperature coefficient above room temperature. The invention may also be utilized to produce diodes, photodiodes, photoelectric resistors, photovoltaic cells, and PN light sources.