Etude et realisation de structures a base d' oxyde de Zinc

Abstract

Transparent conducting oxides (TCO) continue to attract considerable attention in terms fundamental and application, mainly because of their highly exploited properties. Special consideration was given to ZnO which is an n-type semiconductor with excellent optoelectronic properties that give it the potential to be exploited in many areas. In this perspective, we studied in the first part of this work, the influence of the mass concentration of the three elements (Zn, Sn and In) in ZnO- SnO2-In2O3 system on the crystal phase and optoelectronic properties of film elaborated by ultrasonic spray method. No new phase corresponds to the binary or a ternary alloy was observed. Only the phases of pure oxides coexist simultaneously in the deposited films were detected. In the light of this work, we identified the best figure of merit (~ 5.6×10-4 Ω-1 at RZI = 1/8) obtained in the elaborated films of ZnO-SnO2-In2O3 system. In the second part, we studied effects of indium doping and substrate temperature on n-ZnO/p-Si hetero-structures. All elaborated hetero-structures behave as diodes described by the classical equation of the Anderson model, in which it may be necessary to take into account the presence of an oxide layer (SiO 2), interface states and trapping levels located side rather ZnO responsible for a tunnel current. All elaborated hetero-structures exhibit good electrical parameters comparable to those reported in literature.