Rutile Ti1-xCoxO2-δ-based p-type Diluted MagneticSemiconductor Thin Films

다국어 초록 (Multilingual Abstract)

An attempting to produce a p-type diluted magnetic semiconductor (DMS) using Ti1-xCoxO2-δ 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 Ti0.97Co0.03O2-δ (TCO) films deposited at 500 oC 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 oC at 5 x 10-6 Torr 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 1022 /cm3 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.

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