AVS 50th International Symposium
    Semiconductors Wednesday Sessions
       Session SC+EM-WeP

Paper SC+EM-WeP6
Ferromagnetic Co-Implanted Rutile TiO@sub 2@(110) for Spintronics Applications

Wednesday, November 5, 2003, 11:00 am, Room Hall A-C

Session: Poster Session
Presenter: V. Shutthanandan, Pacific Northwest National Laboratory
Authors: V. Shutthanandan, Pacific Northwest National Laboratory
S. Thevuthasan, Pacific Northwest National Laboratory
T. Droubay, Pacific Northwest National Laboratory
S.M. Heald, Pacific Northwest National Laboratory
M.H. Englehard, Pacific Northwest National Laboratory
L.V. Saraf, Pacific Northwest National Laboratory
S.A. Chambers, Pacific Northwest National Laboratory
B.S. Mun, Lawrence Berkeley National Laboratory
R.P. Sears, University of Connecticut
B. Taylor, University of Connecticut
B.S. Sinkovic, University of Connecticut
Correspondent: Click to Email
There is a growing interest in diluted magnetic semiconductor materials due to their potential applications in spintronics area. The ability to efficiently inject spins into multi-layer semiconductor device structures for room temperature operations creates new and exciting possibilities for utilizing DMS materials in semiconductor applications. Some of the dilute magnetic semiconductors with the potential for room temperature spintronics applications include Co-doped ZnO, Mn-doped GaN and Co-doped TiO@sub 2@. Although there are still some issues associated with the growth of single crystal Co-doped anatase TiO@sub 2@, recent experiments show that this material is the most promising candidate because of its room temperature ferromagnetism.@footnote 1,2@ Recently, we have investigated the Co doping in rutile TiO@sub 2@ using ion implantation as a function of implantation temperature and subsequent annealing. Co implantation at room temperature shows that the implanted Co stays as mostly Co metal in TiO@sub 2@(110). Subsequent annealing around 875 K in air promotes Co diffusion towards the surface. During this process Co gets oxidized in the near surface region. Although a portion of the implanted Co appears to be oxidized as a function of implantation temperature up to 875 K, the Co implantation at 1075 K indicates that the implanted Co is mostly oxidized. Some of the implanted Co at 1075 K appears to be substituting for Ti. These samples were characterized using several surface and bulk sensitive techniques including x-ray photoelectron spectroscopy (XPS), Co K and L edge x-ray absorption near edge structure (XANES), and Rutherford backscattering spectrometry (RBS)/channeling. These results with the room temperature vibrating sample magnetometer (VSM) and magneto-optical Kerr effect (MOKE) measurements from these samples will be discussed. @FootnoteText@@footnote 1@ M. Matsumoto et al., Science, 291, (2001) 854.@footnote 2@ S.A. Chambers et al., Appl. Phys. Lett. 79 (2001) 3467.