| 摘要 |
1300187 Epitaxial growth INTERNATIONAL BUSINESS MACHINES CORP 30 June 1971 [17 Aug 1970] 30610/71 Heading B1S A method of growing a crystalline layer on a substrate 34 consists in establishing two regions, 25a and 25b each having a different multicomponent melt, M A and M B , the two regions being in thermal equilibrium with each other and transferring a portion of one melt along with the substrate 34 to the other. The melts M A and M B are both saturated, this being by the dissolving of the materials 44a and 44b in the melts, and the phase diagram of the components of the melts (which comprise the same components, only in different ratios) are such that by mixing melts M A and M B a supersaturated solution is formed, and the substrate receives a coating which is primarily of the composition of the portion of melt transferred when the substrate is (by rotation of substrate holder 16) transferred from one melt to the other. Successive layers can be applied by successive rotations of the holder 16. The process is, in the described embodiments, carried out in a hydrogen atmosphere with the apparatus shown in Fig. 1B within a quartz tube in a furnace. Dopants can be added to the melts through tubes. A further embodiment having three such chambers containing melts, and a substrate in a recession in a disc is also described. The substrate can be of gallium arsenide, with the melts each comprising gallium, aluminium and arsenic, to deposit layers of Ga 1-x Al x A s . |
