IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Thursday Sessions
       Session SS4-ThP

Paper SS4-ThP8
Surface Structures of SiC(0001) Surfaces and Oxygen Adsorption Effects

Thursday, November 1, 2001, 5:30 pm, Room 134/135

Session: Semiconductor Morphology Poster Session
Presenter: T. Aoyama, Nagoya University, Japan
Authors: T. Aoyama, Nagoya University, Japan
A. Ichimiya, Nagoya University, Japan
Y. Hisada, Denso Corporation, Japan
S. Mukainakano, Denso Corporation, Japan
Correspondent: Click to Email
Surface structures of SiC(0001) @sr@3x@sr@3 R30° and 3x3 surfaces have been studied by rocking curves of reflection high energy electron diffraction (RHEED) intensities and auger electron spectroscopy (AES). The @sr@3x@sr@3 reconstruction is observed by annealing the Si pre-deposited specimen in a Si flux at 1000°C for 5 min. The 3x3 reconstruction is observed by successive annealing the @sr@3x@sr@3 surface in a Si flux at 940°C for 5 min. It is obserbed on the auger spectrums of @sr@3x@sr@3 and 3x3 surfaces that Si LVV peak of the @sr@3x@sr@3 is located at kinetic energy of 87 eV and that of the 3x3 surface is located at 91 eV. From the peak to peak ratio of Si LVV to C KLL of these surfaces, it is considered that the 3x3 is Si-rich surface (the ratio: 3) and the @sr@3x@sr@3 surface is Si-poor (the ratio: 0.6). From the structural analysis with RHEED dynamical calculations, it is concluded that the @sr@3x@sr@3 surface is terminated with C trimers on T@sub 4@ or H@sub 3@ sites and the 3x3 surface is terminated with Si pyramidal clusters. Oxygen adsorption effects on the 3x3 surface have been also studied by RHEED and AES. After 10@super 5@ L (1.5x10@super -4@ Torr, 15 min) oxygen exposure at 1000°C on the 3x3 surface, the RHEED pattern changes to 1x1 periodicity and the peak to peak ratio of Si LVV to C KLL and Si LVV to O KLL becomes 0.5 and 0.8, respectively. It is estimated that about 1/3 ML of oxygen atoms are adsorbed on the surface. From the AES results, it is considered that the oxygen atoms are located on embedded sites.