IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Magnetic Interfaces and Nanostructures Tuesday Sessions
       Session MI+EL-TuA

Paper MI+EL-TuA9
Structural and Optical Characterization during Growth of Co on Ga@sub 1-x@In@sub x@As(001)

Tuesday, October 30, 2001, 4:40 pm, Room 110

Session: Spintronics II: Spin Injection & Transport
Presenter: K. L@um u@dge, Technische Universität Berlin, Germany & University of Minnesota
Authors: K. L@um u@dge, Technische Universität Berlin, Germany & University of Minnesota
P. Vogt, Technische Universität Berlin, Germany
B.D. Schultz, University of Minnesota
C.J. Palmstrom, University of Minnesota, United States
W. Braun, BESSY
N. Esser, Technische Universität Berlin, Germany
W. Richter, Technische Universität Berlin, Germany
Correspondent: Click to Email
The growth of magnetic overlayers on semiconductors has received considerable interest due to their potential use in spintronic devices. The interface between the ferromagnet and semiconductor is critical to spin polarized transport across the interface. Thus, it is important to determine dependence of the interfacial structure and the crystalline quality of the ferromagnetic film on the substrate temperature and surface reconstruction. The initial growth of Co on GaAs(001) has been studied using STM, PES and reflectance anisotropy spectroscopy (RAS). The Co tends to be disordered when grown at room temperature. However, crystalline islands are observed at a substrate temperature of 430 K. STM-images taken during Co deposition show, that the substrate surface morphology does not change during deposition despite the change in surface reconstruction. The initial growth on the As-rich c(4x4) surface is different from the growth on the c(8x2) Ga-rich reconstruction. For growth on the c(8x2) surface two different growth modes can be distinguished. At first Co-atoms are adsorbed into rows to form one-dimensional chains. Further deposition results in epitaxial cubic islands. The PES data indicate two metallic components in the Ga3d core level. One is interpreted as resulting from CoxGay and the other from metallic Ga. The As3d core level contains two different components leading to the conclusion of As-Co bonds at the interface and access As on top. The influence of lattice mismatch on the structural and magnetic properties of the epitaxial Co-layer will be studied by Co growth on Ga@sub 1-x@In@sub x@As(001).