A process for the preparation of a body with a transition between two different materials, in particular semiconductor materials and prepared by this process body

摘要

1,051,397. Jointing. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. Nov. 16, 1965 [Nov. 19, 1964], No. 48621/65. Heading B3V. [Also in Division H1] Two parts are joined by the action of a beam of radiation all or most of the energy of which is chosen to be in a frequency range such that the radiation will be selectively absorbed by one of the parts. The beam is directed through that part which does not absorb the radiation and is absorbed by the second part substantially at the interface between the two parts to weld them together. The process may be carried out in air, in vacuo, in a protective atmosphere, in an etching gas or liquid, in an atmosphere repressing evaporation of volatile components, or, to bond materials such as cubic tin which are unstable to heat, in a liquid coolant. Uses suggested are the formation of hetero junctions between different semi-conductors, of metal to semi-conductor bonds, and of bonds between two pieces of the same basic semi-conductor having widely different dopant concentrations. In an example a germanium body (#E = 0À9eV) is joined to a cadmium sulphide body (#E = 2À4eV) using a ruby laser (6900 Š- 1À8 eV). Bonds may be made at spaced locations on the bodies and several wafers split from the composite body e.g. by sawing between the bonds. During bonding, carried out in air or in vacuo, the bodies may be held together under pressure and/or preheated to vary the conditions of bonding. Radiation of wavelengths 9000 Š- 18,600 Š may be used to bond germanium to gallium arsenide (#E = 1À4 eV).