Diluted Magnetic Semiconducting Ti1 − xCox O 2 Thin Films Grown onto SiO2 ( 200 nm ) / Si Substrates by Liquid-Delivery MOCVD

Abstract

Anatase thin films onto substrates at 400°C using liquid-delivery metallorganic chemical vapor deposition (MOCVD) were successfully prepared and the ferromagnetic properties investigated through microstructural analysis by transmission electron microscopy and high-resolution scanning Auger microscopy as a function of Co-doping concentration. Ferromagnetic behaviors of polycrystalline films were observed at room temperature and the magnetic and structural properties depend critically on the Co distribution, which varies widely with Co-doping concentration. Annealed thin films with showed a homogeneous structure without any clusters, and pure ferromagnetic properties of thin films are attributed only to the phases. In the case of thin films above Co-rich clusters are formed in homogeneous phases. The solid solubility of Co was approximately 5 atom % in polycrystalline thin films. clusters with a c axis preferred orientation decrease the value of (coercive field) and increase the saturation magnetic field. The polycrystalline anatase thin films prepared by liquid-delivery MOCVD have an advantage for high-density device application in ferromagnetic semiconductor fields. © 2004 The Electrochemical Society. All rights reserved.