MBE growth and properties of Cr-doped ZnTe on GaAs(001)

Cr-doped ZnTe diluted magnetic semiconductor thin films were grown on semi-insulating GaAs [001] substrates at low temperature by solid-source molecular-beam epitaxy. Zn1−xCrxTe samples with Cr concentrations x=0.026 and x=0.141 were prepared. The magnetization versus magnetic field (M–H) measurement showed a clear hysteresis loop at low temperature for these samples. For higher Cr doping with nominal Cr concentration of x>0.18, we obtained a Curie temperature of 365 K; the highest reported so far for thin film sample. However, this strong ferromagnetic momentum could possibly be due to Cr1−δTe precipitate in the Cr-doped ZnTe system.