Patent GB-1093402-A (GB)
Title: Improvements in and relating to semiconductor recombination radiation sources
IPC: H05B33/14
Filed: 1965-02-18
Abstract: A recombination radiation source comprises zinc-doped aluminium arsenide.  A metal-semi-conductor contact or a PN junction can be used to produce the radiation.  Such a source may be made by cooling a melt of aluminium, zinc and arsenic to give the required compound. The melt may contain 0.1 to 50 atom per cent Zn, but may additionally contain Sn or Pb as donors and even added oxide or an oxygen containing atmosphere to give oxygen doping.  A melt of Al-Zn may be formed and solid or gaseous As added thereto, alternatively an Sn-Zn melt preferably containing Al may have AlAs added thereto.  In another embodiment, Zn3As2 may be added to an Al alloy preferably containing Zn.  The excess of metal in the final product, generally Al, may be removed using a bromo or iodo-hydrocarbon, e.g. 1,2-dibromoethane.  The melt may be cooled to crystallize out the desired compound alternatively, a mono-crystal may be drawn from the melt.  GaAs or InAs may also be used as sources of As and may even produce one or more PN junctions in situ.  In specific embodiments transparent crystals of Zn-doped A1As are produced using sealed tubes or crucibles in a hydrogen atmosphere, heated to specified temperature ranges and cooled at specified rates.  The crystals may be used at -190 DEG  C. at 15 V and 3-4 mA, when they give red radiation with a maximum at 1.9 eV. Silver paste electrodes may be attached to the crystal. The source may be used as a lamp in signal transmission systems having electroluminescent cells and in image intensifiers comprising photo-electric and electroluminescent layers.ALSO:A recombination radiation source comprises zinc-doped aluminium arsenide.  Such a source may be made by cooling a melt of aluminium, zinc and arsenic to give the required compound. The melt may contain 0.1 to 50 atom % Zn, and additionally contain Sn or Pb as donors and even added oxide or an oxygen containing atmosphere to give oxygen doping.  A melt of Al-Zn may be formed and solid or gaseous As added thereto, alternatively an Sn-Zn melt preferably containing Al may have AlAs added thereto.  In another embodiment, Zn3As2 may be added to an Al alloy preferably containing Zn.  The excess of metal in the final product, generally Al, may be removed using a bromo or iodo-hydrocarbon e.g. 1, 2-dibromoethane. The melt may be cooled to crystallize out the desired compound alternatively, a mono-crystal may be drawn from the melt.  GaAs or InAs may also be used as sources of As and may even produce one or more pn junctions in situ.  In specific embodiments transparent crystals of Zn-doped AlAs are produced using sealed tubes or crucibles in a hydrogen atmosphere, heated to specified temperature ranges and cooled at specified rates.ALSO:A recombination radiation source comprises zinc-doped aluminium arsenide.  Such a source may be made by cooling a melt of aluminium, zinc and arsenic to give the required compound. The melt may contain 0.1 to 50 atom per cent Zn, and may additionally contain Sn or Pb as donors and even added oxide or an oxygen-containing atmosphere to give oxygen doping. A melt of Al-Zn may be formed and solid or gaseous As added thereto, alternatively an Sn-Zn melt preferably containing Al may have AlAs added thereto.  In another embodiment, Zn3As2 may be added to an Al alloy preferably containing Zn.  The excess of metal in the final product, generally Al, may be removed using a bromo or iodo-hydrocarbon, e.g. 1,2-dibromoethane. The melt may be cooled to crystallize out the desired compound; alternatively, a mono-crystal may be drawn from the melt. GaAs or InAs may also be used as sources of As and may even produce one or more PN junctions in situ.  In specific embodiments transparent crystals of Zn-doped AlAs are produced using sealed tubes or crucibles in a hydrogen atmosphere, heated to specified temperature ranges and cooled at specified rates. missing page 194