Magneto-transport Properties of Cobalt doped Indium Oxide Dilute Magnetic Semiconductors
- PDF / 788,775 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 45 Downloads / 206 Views
1032-I10-01
Magneto-transport Properties of Cobalt doped Indium Oxide Dilute Magnetic Semiconductors N. Mamidi1, R. K. Gupta1, K. Ghosh1, S. R. Mishra2, and P. K. Kahol1 1 Department of Physics, Astronomy, and Materials Science, Missouri State University, Springfield, MO, 65897 2 Department of Physics, The University of Memphis, Memphis, TN, 38152 ABSTRACT Recently, oxide-based dilute magnetic semiconductors (DMS) have attracted an immense research interest to the scientists due to the possibility of inducing room temperature ferromagnetism and potential uses in novel spintronic devices. Indium oxide (In2O3), a transparent opto-electronic material, is an interesting prospect for spintronics due to its unique combination of magnetic, electrical, and optical properties. High quality thin films of Co-doped In2O3 DMS were grown on quartz substrates using pulsed laser deposition technique. All the films have been characterized using different techniques such as x-ray diffraction, Raman spectroscopy, optical transmission spectroscopy, electrical resistivity, and Hall Effect measurement. The effect of growth temperature and oxygen pressure on the electrical, magnetic, and optical properties of these films have been studied in detail. The optical transparency in all the films is high. It has been observed that the optical transparency depends on growth temperature and oxygen pressure. The electrical parameters such as resistivity, carrier concentration, and mobility strongly depend on both oxygen pressure and growth temperature. The temperature dependence resistivity measurements shows transition form semiconductor to metallic behavior for these films. INTRODUCTION Transition metal doped dilute magnetic semiconductors (DMS) have attracted much attention not only due to their applicability in spintronic devices but also for development of transparent ferromagnetic material [1]. Indium oxide, a transparent opto-electronic material, having a wide band gap (energy band gap Eg ~ 3.70 eV), is an interesting prospect for spintronics due to its unique combination of magnetic, electrical, and optical properties [2]. The effect of doping on the electrical conductivity, optical transparency and magnetic properties of In2O3 has been studied [3, 4]. Hong et al have observed room temperature ferromagnetism in cobalt doped In2O3 [5]. In this work, we are reporting on the fabrication and characterization of cobalt doped indium oxide thin films by pulsed laser deposition. In particular, we have studied the effect of substrate temperature and oxygen pressure on the optical, electrical and structural properties of these films. EXPERIMENT A cobalt doped In2O3 (ICO) target for the pulsed laser deposition (PLD) was prepared by standard solid-state reaction method using high purity In2O3 (99.999 %) and Co3O4 (99.999 %).
Required amounts of In2O3 and Co3O4 were taken by molecular weight and mixed thoroughly. The well-ground mixture was heated in air at 850 ûC for 12 hours. The powder mixture was cold pressed using hydraulic press at 15 tons loa
Data Loading...