AVS 47th International Symposium
    Semiconductors Monday Sessions
       Session SC+EL+SS-MoA

Paper SC+EL+SS-MoA3
Scanning Tunneling Microscopy of Impurity Dimers on Hydrogen-Terminated Si(100)-2x1 Surface

Monday, October 2, 2000, 2:40 pm, Room 306

Session: Reactions on Semiconductors
Presenter: S. Matsuura, University of Tokyo, Japan
Authors: S. Matsuura, University of Tokyo, Japan
M. Fujimori, Hitachi, Ltd., Japan
S. Heike, Hitachi, Ltd., Japan
Y. Suwa, Hitachi, Ltd., Japan
H. Kajiyama, Hitachi, Ltd., Japan
T. Onogi, Hitachi, Ltd., Japan
K. Kitazawa, University of Tokyo, Japan
T. Hashizume, Hitachi, Ltd., Japan
Correspondent: Click to Email
We report a new dimer structure on a hydrogen-terminated n-type Si(100)-2x1-H surface found by a scanning tunneling microscopy (STM). The dimer structure is observed almost same as regular surface Si dimers at filled state, at empty state, however, is observed as different structure showing spatial variation of electronic density of states. Similar results were obtained in the case of As-doped surface. The surface density of the structures derived from measurement of the samples with different dopant concentrations was found to be proportional to the dopant density. Electronic structures calculated by first-principles calculations for a phosphorous dimer or an arsenic dimer on the Si(100)-2x1-H surface are in good agreement with the bias dependent STM images of the newly-found structure on the P-doped or As-doped Si(100) surface, respectively. We concluded that the dimer structure represents dopant atoms incorporated on the Si surface and forming a dimer. The calculation also revealed that the surface phosphorous and arsenic atoms are more stable forming dimers than being isolated on the hydrogen-terminated Si surface.