IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Semiconductors Tuesday Sessions
       Session SC-TuA

Paper SC-TuA3
Indium Segregation and its Effect on Interfacial Bonding at the GaSb-on-InAs Heterojunction: A Cross-Sectional Scanning Tunneling Microscopy Study@footnote 1@

Tuesday, October 30, 2001, 2:40 pm, Room 124

Session: Semiconductor Heterojunctions
Presenter: J. Steinshnider, Texas A&M University
Authors: J. Steinshnider, Texas A&M University
M. Weimer, Texas A&M University
E.M. Shaw, University of Iowa
Z. Mi, University of Iowa
T.C. Hasenberg, University of Iowa
R. Kaspi, Air Force Research Laboratory
Correspondent: Click to Email
We describe how scanning tunneling microscopy (STM) may be used to determine the chemical composition across the nearly-lattice-matched, non-common-atom GaSb-on-InAs heterojunction with atomic-scale precision. An ideal, compositionally-abrupt GaSb-on-InAs interface is composed of either InSb-like or GaAs-like bonds whose character is easily distinguished with STM.@footnote 2@ Indium segregation, on the other hand, leads to compositional grading within the subsequent GaSb layers that compromises interfacial abruptness. We have quantified the indium fraction in successive gallium planes and find this compositional grading is described by the same microscopic model previously applied to antimony segregation at the InAs-on-GaSb interface.@footnote 3@ We discuss how indium segregation at the GaSb-on-InAs heterojunction is linked with the surface reconstruction of the underlying InAs template and consider the effect of this segregation on the interfacial bonding. @FootnoteText@ @footnote 1@Work supported by the National Science Foundation (Division of Materials Research) and Air Force Research Laboratory @footnote 2@J. Steinshnider, M. Weimer, R. Kaspi, and G.W. Turner, Phys. Rev. Lett., 85, 2953 (2000). @footnote 3@J. Steinshnider, J. Harper, M. Weimer, C.-H. Lin, S.S. Pei, and D.H. Chow, Phys. Rev. Lett., 85, 4562 (2000).