Room-Temperature Fabricated Zncoo Diluted Magnetic Semiconductors

(0002) textured and epitaxial ZnCo(0.07)O films were fabricated at room temperature by ion beam deposition on Si substrates. Hall measurement revealed that ZnCo(0.07)O films were n-type semiconductors with carrier concentrations higher than 10(19)/cm(3). The carrier concentration of ZnCo(0.07)O can be manipulated by controlling the oxygen flow rate during deposition or by postannealing. The saturation magnetization and magnetoresistance ratios strongly depended on the carrier concentration. In addition, epitaxial (0002) ZnCo(0.07)O films, grown on Cu underlayers, showed room-temperature ferromagnetism, which may be potentially used for spintronic devices. (c) 2007 American Institute of Physics.