Nanoscale Order in ZnTe:(Cd, O)

Abstract

Self-assembling of 1O4Cd identical tetrahedral clusters resulting to nanoscale order in ZnTe:(Cd, O) is presented. Such co-doping transforms ZnTe into CdxZn1-xOyTe1-yalloy. The decrease of the strain energy is a cause of this phenomenon. The self-assembling conditions are obtained by the minimum condition of the free energy of ZnTe:(Cd, O) at the Cd and oxygen in the dilute and ultra dilute limits, respectively. An occurrence of 1O4Cd clusters and completion of self-assembling (all oxygen atoms are in clusters) are results of the continuous phase transitions. The temperature of the occurrence of self-assembling does not depend on the oxygen content and it is a function of Cd concentration only. CdxZn1-xOyTe1-ywith all oxygen atoms in clusters may be obtained in temperature ranges fromT= 270 °C (x= 0.002,y= 1×10-4) toT= 620 °C (x= 0.02,y= 1×10-4) and fromT= 240 °C (x= 0.005,y= 0.001) toT= 580 °C (x= 0.02,y= 0.001).