
174 Semiconductor Device-Based Sensors for Gas, Chemical, and Biomedical Applications
© 2011 by Taylor & Francis Group, LLC
ferromagnetism. At 10 K, the coercive eld in the 3 at% Mn-doped sample is 250 Oe. It must be
noted that other possible explanations for hysteretic M versus H behavior that are remotely possible
include superparamagnetism and spin-glass effects.
153–156
Magnetization measurements were also
performed on Sn:ZnO crystals that were not subjected to the Mn implant. This was done to elimi-
nate the possibility that spurious transition metal impurities might be responsible for the magnetic
response. The Sn-doped ZnO crystals exh ...