| 摘要 |
1289598 Gallium compounds; gallium arsenide; glalium phosphide CONSORTIUM FUR ELEKTROCHEMISCHE INDUSTRIE GmbH 6 Nov 1970 [6 Nov 1969] 52953/70 Heading C1A Epitaxial layers of gallium-containing III-V semi-conductor compounds are prepared by a process in which Gallium (I) chloride is produced by heating a stream of Gallium (III) chloride and hydrogen to a temp. of 700‹ to 900‹ C. in the presence of an element selected from Groups Va, VIa or VIII of the Periodic System according to Mendeleev, the gallium (I) chloride so formed then being reacted at a temp. of 600-700‹ C. with an element of Group Vb of the Periodic System, this element being produced by the decomposition of at least one compound of the element which has been added in gaseous form to the gas stream before or after the gallium (III) chloride reduction step, the resulting III-V compound being deposited on an adjacent substrate. Preferred catalysts are Nb, Ta, Ni, Pd, Pt, W or Mo, alloys or mixtures thereof. The amount of gallium (III) chloride in the initial gas stream is preferably 0À05 to 1% by volume, and this stream may also contain up to 90% by volume argon. There may be a temp. difference of at least 100‹ C. in the temp. at which the two stages of the reaction are carried out. The Vb element involved may be P or As and they may be utilized as their halides or hydrides, e.g. AsH 3 , AsCl 3 , PH 3 or PCl 3 . Doping materials, e.g. Cd, Zn, Se or Te may be added to the second stage of the reaction, as their organic compounds, e.g. diethyl zinc or as hydrogen selenide or telluride. Chromium may also be added as a doping agent, e.g. as chromyl chloride or Cr(CO) 6 . The substrate may be a monocrystalline semi-conductor, e.g. GaAs, GaP or Si, or it may be a monocrystalline insulator, e.g. sapphire or Mg Al spinel. |
