AVS 45th International Symposium
    Surface Science Division Wednesday Sessions
       Session SS2-WeA

Paper SS2-WeA5
Direct Observation of Synchrotron-Radiation-Stimulated Decomposition of SiO@sub 2@ Thin Films on Si(111) Surfaces using Scanning Tunneling Microscopy

Wednesday, November 4, 1998, 3:20 pm, Room 309

Session: Photochemistry and Deposition
Presenter: T. Urisu, Institute for Molecular Science, Japan
Authors: T. Miyamae, Institute for Molecular Science, Japan
T. Urisu, Institute for Molecular Science, Japan
S. Hirano, Institute for Molecular Science, Japan
H. Uchida, Toyohashi University of Technology, Japan
T. Yagi, Toyohashi University of Technology, Japan
I. Munro, Institute for Molecular Science, Japan
Correspondent: Click to Email
Synchrotron radiation (SR) stimulated decomposition of silicon dioxide thin films on Si(111) surfaces were observed by using a ultrahigh vacuum scanning tunneling microscopy (UHV-STM) and Low energy electron diffraction (LEED). SiO@sub 2@ films were shown to be almost removable by SR irradiation. Si(111)-(7 by 7) reconstructed structure were observed by LEED after two hours SR irradiation at surface temperatures as low as 650 C°. In spite of the observation of clear 7 by 7 LEED pattern, the STM images did not show clean and flat surface at this temperature. The clean (7 by 7) reconstructed surface was generated after two hours irradiation at a surface temperature of 700 C°. Analysis of the evolution in the clean region suggests that the desorption mechanism may be different between thermal and SR stimulated desorption processes. The results show that the feasibility of this technique for low-temperature cleaning of silicone surface is demonstrated.