DX-CENTERS AND OTHER DEEP LEVELS IN IN0.13GA0.82AS0.28P0.72

Deep donor levels in group VI impurity-doped In0.18Ga0.82As0.28P0.72 g rown on GaAs0.61P0.39 substrates by liquid phase epitaxy are studied b y deep level transient spectroscopy and thermally stimulated capacitan ce measurements. The activation energies of deep donor levels are foun d to be 0.26, 0.23, and 0.14 eV for S-, Se-, and Te-doped In0.18Ga0.82 As0.28P0.72, respectively, and all of the samples show persistent phot oconductivity. It is suggested that group VI impurities in In0.18Ga0.8 2As0.28P0.72 form DX centers. Two deep levels with the activation ener gies of 0.15 and 0.48 eV are detected in undoped sample.