Diluted Magnetic Semiconductor Nanomaterials Fabrication by a Chemical Vapor Deposition Method
Well-aligned DMS Zn1-xMnxO nanowires and nanorods were successfully synthesized in-situ using a chemical vapor deposition method. Low-dimensional nanostructures such as bowls and cages were deposited on a silicon surface downstream of the tube furnace. Variation of reaction temperature and Mn doping level were investigated on structure and properties of the as-grown nanomaterials. The as-grown nanowires and naorods are single crystalline wurtzite structure and possess a growth direction along the c axis. At 850 ºC, the most optimistic condition for ZnO crystal growth was obtained. At high reaction temperature 950ºC, Mn2+ were substitutionally doped into ZnO lattice, resulting in room-temperature ferromagnetic coupling with a saturated magnetization of 0.25emu/g. The ferromagnetic interaction is weakened, however, by larger concentration of Mn, due to the antiferromagnetic coupling of direct superexchange interaction between Mn2+. The well-aligned DMS 1-dimensional Mn doped ZnO nanostructures have great potential for application in spintronic nanodevices.
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