Temperature change of the conductivity type in semi-insulating InP double doped with Zn and Fe

Abstract
Semi-insulating InP single crystals double doped with Zn and Fe and single doped with Fe were grown by the Czochralski technique. Resistivity and Hall coefficient were measured at temperatures between 230 K and 420 K. The Hall coefficient shows an extremum at about 250 K and a change of sign to positive below about 235 K in InP:(Zn+Fe). The effect is discussed in terms of the strength of electron and hole mixed conductance at various temperatures on account of a shift of the Fe deep level with temperature.