Fabrication of phosphorus-doped ZnO quantum dots by metal organic chemical vapor deposition

Phosphorus doped ZnO quantum dots (QDs) have been fabricated on Si substrates by metal organic chemical vapor deposition method without using additional thermal activation processes. Single-crystal phosphorus doped ZnO quantum dots (QDs) have the average diameter of 20 nm and show preferred orientation with (001) direction. The incorporation of phosphorus in ZnO QDs was identified by x-ray photoelectron spectroscopy (XPS). The acceptor doping was confirmed by the valence band XPS, which demonstrated the tuned Fermi level of the ZnO QDs resulting from the acceptor doping. Quantum confinement effect for the phosphorus doped ZnO QDs is clearly observed from their room temperature photoluminescence spectra.