Photoconductivity of gamma-irradiated Znse (Te)/ZnO:O and ZnSe(Te)/ZnO:O,Zn nanogeterojuctions

Abstract

Possibility of enhancing the photoconductivity of ZnSe (0.2%Те)/ZnO:O nanoheterojunction was investigated under effect of thermo-treatment in zinc vapor followed by 60Сo gamma-irradiation in air to the dose of 106 Gy by means of generation of impurity-defect complexes. The obtained ZnSe (0.2%Te)/ZnO:O,Zn nanoheterojunction had an electron conductivity with the activation energy 0.33 eV that is caused by thermo-stimulated transfer of charge carriers on the stable resonance level Γ6v= 5.76 eV in the conducting band. The significant photoconductivity growth from 10-10 to 10-5 Ω-1 was achieved at 300 K, and also a broad band (480-1100 nm) light scattering at free carriers occurred due to formation of additional stable associates (OSe0TeSe0VZn-), (OSe0VZn-)- or (OSe0VZnMeZnIIIZni) at the interface between the matrix crystal p-ZnSe(0.2%Te):O,Zn and nanocrystallite n-ZnO of 40 nm size, where amorphous phase layer of 1.2 nm was also grown.