Donor-related deep levels in In1-xGaxAsyP1-y

Donor-related deep levels in In1-xGaxP and In1-xGaxAsyP1-y grown on the lattice-matched substrates are reviewed. The S-, Se-, and Te-doped samples show the characteristic deep levels corresponding to the donor species. They are revealed to have the same properties as the well-known DX center in AlGaAs - persistent photoconductivity, variation of thermally stimulated capacitance, constancy of activation energy with alloying, bandstructure-dependent deep level density. It is concluded that the S, Se, and Te donors form DX centers in In1-xGaxP and In1-xGaxAsyP1-y. Furthermore: the origin and the peculiar property of deep levels observed in undoped In0.5Ga0.5P and In1-xGaxAsyP1-y, respectively, are also reviewed.