Deep level transient spectroscopy of hole traps in Zn-annealed ZnTe

Hole traps in Schottky barrier diodes of p-ZnTe that had previously been annealed in liquid Zn have been investigated using Deep Level Transient Spectroscopy (DLTS). Three traps have been investigated in 3etail and have activation energies of between E_v = 0.28 eV and E_v + 0.59 eV. All traps are assigned to acceptor defects because of their large capture cross sections for holes and one of these is tentatively assigned to a V_Zn native acceptor. From capacitance-temperature plots we deduce that Cu_Zn is the dominant shallow acceptor in as-grown material but after annealing the Cu_Zn concentration is reduced and a yet shallower acceptor, probably Li_Zn, predominates.