Effect of Growth Temperature on Structural and Magneto-Transport Properties of Co-Doped In₂O₃ Diluted Magnetic Semiconductors

Abstract

Recently, Diluted magnetic semiconductors (DMS) based on transition metal oxides have attracted considerable attention due to their potential applications in spintronic devices. In₂O₃ is a wideband gap semiconductor with unique optical and electrical properties. The high conductivity of In₂O₃ is due to presence of interstitial oxygen vacancy. By doping with the transition metal such as cobalt, the possibility of room temperature ferromagnetism is expected. Thin films of Co-doped In₂O₃ diluted magnetic semiconductor have been grown on c-plane sapphire single crystals using pulsed laser deposition technique. Different characterizations such as x-ray diffraction, atomic force microscopy, and magneto-transport have been carried out to study the effect of growth temperature on the structural, electrical, and magnetic properties of these films. The films grown at high temperature have preferred orientation along (222) direction, while films grown at low temperature show amorphous nature. It is observed that electrical properties of the films strongly depend on growth temperature. The resistivity of the films decreases with increase in growth temperature. On the other hand, mobility of the films increases with increase in growth temperature. This could be due to improvement in crystallinity of the films.