Dependence of ferromagnetic properties on conductivity for As-doped p-type (Zn0.93Mn0.07)O layers

The As-doped p-type (Zn0.93Mn0.07)O layers show a strong dependence of their ferromagnetic properties on the hole conductivity that were controlled through the modification of negative background-charge density by changing the oxygen partial pressure during the initial growth stage before As doping. Curie temperature and spontaneous magnetization were observed to be increased as the hole conductivity increases. This result was confirmed to originate from stabilizations of incorporated Mn2+ ions and doped As acceptors, which can give rise to long-range ferromagnetic coupling. (C) 2008 American Institute of Physics.