Rutile Ti1-xCoxO2-delta-based p-type Diluted Magnetic Semiconductor Thin Films

An attempting to produce a p-type diluted magnetic semiconductor (DMS) using Ti1-xCoxO2-delta thin films was made by suitable control of the deposition parameters including deposition temperature, deposition pressure, and doping level using a pulsed laser deposition method. The Ti1-xCoxO2-delta (TCO) films deposited at 500 degrees C at a pressure of 5 x 10(-6) Torr showed an anomalous Hall effect with p-type characteristics. On the other hand, films deposited at 700 degrees C at 5 x 10(-6) Ton showed n-type behaviors by a decreased solubility of cobalt. The charge carrier concentration in the p-type TCO films was approximately 7.9 x 10(22) /cm(3) at 300 K and the anomalous Hall effect in the p-type TCO films was controlled by a side jump scattering mechanism. The magnetoresistance (MR), measured at 5 K in p-type TCO films showed a positive behavior in an applied magnetic field and the MR ratio was approximately 3.5 %. The successful preparation of p-type DMS using the TCO films has the potential for use in magnetic tunneling junction devices.