Electromigration and Polarization in Schottky Contacts CdTe Based Compounds

Abstract

In this work, studies of major transient phenomena, electromigration and polarization, are presented. Electromigration measurements have been carried out at different temperatures on low resistivity ptype CdTe sample with two Au Schottky contacts. Comparative measurements at different temperatures succeeded by etching the anode contact and a thin later below after each measurement and making a new contact. Temporal conductance of the depletion layer was measured and mobility, acceptor concentrations, diffusion coefficients of the mobile ions and the activation energy of the electromigration process were extracted. Pockels effect technique has been used to study the polarization effect in high resistivity CdZnTe with Au Schottky contacts. Time dependence of Pockels effect measurements was assessed at different temperatures. The analysis of these data revealed that the energy of the deep donor level responsible for the polarization effect in the studied sample is Ec-0.8771eV, with capture cross section 8.71x10 -13 cm 2 .