INDIUM DOPING OF CDTE GROWN BY MOLECULAR-BEAM EPITAXY

We report on n-type indium doping of CdTe films grown by molecular bea m epitaxy on (001) GaAs substrates. By adjusting the flux of In atoms we can precisely control the carrier concentration over three orders o f magnitude - from 8 x 10(14) up to 1.3 x 10(18) cm(-3). In agreement with earlier reports we confirmed that Cd overpressure plays an import ant role in the doping process. The doping appears to be most effectiv e for Cd/Te pressure ratio of 1.5. For this value of Cd/Te pressure ra tio essentially 100% efficiency of doping is achieved at low In concen trations (< 10(18) cm(-3)). At higher In concentrations acceptor impur ities compensate shallow donors limiting the concentration of free car riers.