WERKWIJZE VOOR HET OP EEN MONOKRISTALLIJN SUBSTRAAT AAN- BRENGEN VAN EEN EPITAXIALE MONOKRISTALLIJNE LAAG HALFGE- LEIDEND MATERIAAL VANUIT EEN SMELT.

摘要

1299610 Semi-conductor processing PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 30 Dec 1969 [31 Dec 1968] 63247/69 Heading H1K [Also in Division B1] In the formation on a monocrystalline substrate of a semi-conductor layer by liquid phase epitaxy the material for the liquid phase is melted and only then brought into contact with the substrate, contact being effected by the use of a slide forming part of the growth crucible. As shown in Fig. 1 the substrate 2 lies on the floor of the crucible and the melt 10 is formed above the slide 3 which is spaced slightly from the substrate. At the desired melt temperature the slide is pulled back to deposit the melt on the substrate. The entire solute may be crystallized or the slide (the upper side of the leading edge of which may be tapered) may be introduced at a particular lower temperature to separate off the bulk of the melt. As shown in Fig. 4 the substrate 27 is instead carried in a recess 28 in the slide 24, the slide being inserted when the desired melt temperature is reached. (It need not then be a consequence that the substrate is heated during fusing of the melt). The crucible shown has two compartments the melts of which may contain the same semiconductor with different impurity concentrations and/or impurities of different conductivity type or the two melts may contain different semi-conductors. The substrate may be placed successively or alternately in the two molts to grow two or more superimposed layers. The substrate may be semi-conductor or monocrystalline alumina. Boron nitride or quartz may be used for the crucible. A typical melt may be made by saturating gallium with arsenic or with gallium arsenide at 900� C. Deposition from the melt may be started at about this temperature and, for example, stopped when the melt temperature has fallen to 500� C.