Properties of ZnO influenced by P concentration

Abstract

The properties of ZnO were found to be influenced by P concentration. Upon increasing P concentration in ZnO, up to small values of less than 0.1 at. %, the as-deposited ZnO is found to undergo a change from n-type to p-type character. The change is accompanied by a redshift of the optical band gap energy and an increase in the lattice constants of ZnO, which can be attributed to substitution of O by P. A further increase in P concentration, up to 0.4 at. %, leads to a decrease in both lattice constants and energy band gaps of the samples, compared to those of undoped ZnO. Additionally, the electrical conductivity of samples stopped increasing for high P concentrations and became an insulator at P=0.4 at. %. Possible mechanisms for these effects were investigated and discussed. © 2009 American Institute of Physics.