Spatial correlations of In-donor charges in CdTe layers

Abstract

We present experimental evidence that indium donors in CdTe localize electrons in a spatially correlated manner. We have studied the Hall mobility, μH, as a function of the electron concentration, nH, at T = 77 K. Three methods leading to changes of nH have been used (i) high pressure freeze-out of electrons onto localized states of In-donors, (ii) the persistent photoconductivity effect, and (iii) a subsequent annealing of the sample. Each method causes a related modification in a degree of spatial correlations in the arrangement of donor charges. As a consequence, different values of μH correspond to the same value of nH.