The results of deep-level transient spectroscopy investigations in n-type CdTe layers grown by the molecular-beam epitaxy technique on lattice-mismatched GaAs substrates were described. Three electron traps and one hole trap, at rather low concentrations of the order of 1013/cm3, were revealed in the deep-level transient spectra measured under various bias conditions of Schottky diodes prepared on the as-grown CdTe layers. One of the electron traps was attributed to electron states of dislocations on the ground of the logarithmic capture kinetics for capture of electrons into the trap states. The other three traps, displaying exponential capture kinetics, were attributed to native point defects produced during the epitaxial growth of CdTe. The microscopic nature of the defects responsible for the traps was considered, taking into account recent results of first-principles calculations of the properties of dominant native defects in CdTe.

Capture Kinetics at Deep-Level Defects in MBE-Grown CdTe Layers. K.Olender, T.Wosinski, A.Makosa, S.Kret, V.Kolkovsky, G.Karczewski: Semiconductor Science and Technology, 2011, 26[4], 045008