Preparation and magnetoresistance of submicron CrO2 thin film on poly-crystal SnO2 film

AbtractThe submicron chromium dioxide (CrO2) thin films have been fabricated on poly-crystal stannic oxide (SnO2) films by atmospheric pressure chemical vapor deposition method. At low temperature, the CrO2 thin film has sharp increase in the MR at low fields. This should be mainly attributed to spin-dependent tunneling through grain boundaries between adjacent CrO2 grains. At high temperature, the magnetoresistance (MR) of CrO2 thin film has small value and shows linear dependence on applied magnetic field. The resistivity of CrO2 thin film decreases significantly as temperature increases, which can be best described by the fluctuation-induced tunneling model below 220 K. The MR for the CrO2 thin film on SnO2 film also decreases rapidly with increasing temperature.