Sb-doping of ZnO: Phase segregation and its impact on p-type doping

The incorporation of antimony (Sb) in pulsed-laser deposited ZnO thin-films was investigated employing scanning electron microscopy, Raman spectroscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction (XRD) measurements. It is shown that an increase in the Sb concentration in the target leads to a significant deterioration of the sample structure which is accompanied by a decrease in the deposition rate. Furthermore, the dopant transfer factor depends strongly on the deposition temperature and exhibits a steplike behavior above 600 degrees C. XRD measurements clearly show that significant Sb-O phase precipitations occur. The implications of our data on p-type doping of ZnO are discussed. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3570691]