| 摘要 |
1,173,939. Semi-conductor devices. INTERNATIONAL BUSINESS MACHINES CORP. 5 Oct., 1967 [13 Jan., 1967], No. 45427/67. Heading H1K. [Also in Division C7] A II-V, III-V and II-VI semi-conductor compound formed by a metal selected from Zn, Cd, Hg, Al, Ga, In and an element selected from P, As, Sb, S, Se, Te are prepared by cathodic deposition from a fused salt solution including ions of the chosen metal and element, the applied potential being sufficient to cause simultaneous deposition of the metal and element to form the desired compound. Preferably the constituent which is deposited in excess of its stoichiometric ratio in the compound is volatile at the temperature of the fused salt bath and is one of the Group V or Group VI elements. Typically the semi-conductor compound has the zinc blende structure and if desired it may be epitaxially deposited on a cathode formed by a single crystal of silicon. As described the fused bath includes alkali metal halides as diluent. The cell may comprise a tantalum crucible or quartz coated with graphite and serves also as anode while a graphite rod may serve as cathode. Germanium may also be used as a cathode. An inert cell atmosphere-argon, helium or nitrogen-is provided. The bath may also include compounds of dopants for the semiconductor which are codeposited with it. Examples are given of depositing crystals of GaP from baths containing Ga 2 O 3 and NaPO 3 ; A1P from baths containing Al 2 O 3 and NaPO 3 ; 8. of growing epitaxially on a Si crystal ZnSe from a bath containing ZnCl 2 and SeCl 4 . GaP doped with Zn is produced from a bath consisting of NaF, NaPO 3 , Ga 2 O 3 and ZnO and is deposited on a crystal of Si. Similarly by including also Na 2 SeO 4 in the bath, a photoluminescent GaP doped with both Zn and Se is obtained. By depositing first P-type GaP doped with Zn and then coating this with N-type GaP doped with Se, a PN junction is formed suitable for an electroluminescent diode which emits red light on the passage of current. |
