AVS 49th International Symposium
    Surface Science Monday Sessions
       Session SS1-MoM

Paper SS1-MoM1
STM Studies of the Role of Copper in Chlorosilane Desorption Mechanisms from Cl-exposed Cu/Si(111) Surfaces

Monday, November 4, 2002, 8:20 am, Room C-108

Session: Adsorption and Chirality
Presenter: D.V. Potapenko, Rutgers University
Authors: D.V. Potapenko, Rutgers University
S.E. Sysoev, Rutgers University
A.V. Ermakov, Rutgers University
D. Maithil, Rutgers University
B.J. Hinch, Rutgers University
Correspondent: Click to Email
TPD experiments show that the presence of copper on a Si(111) surface significantly influences the desorption kinetics of chlorosilanes from chlorine-exposed Si(111) surfaces. The major desorption peak (of SiCl@sub 2@) occurs at ~600@degree@C from Cl-covered Cu/Si(111) surfaces, and complex desorption kinetics are exhibited that indicate an active role of chlorine-free sites in the SiCl@sub 2@ desorption process. In contrast, SiCl@sub 2@ desorption from Si(111) 7x7 surfaces is observed at ~650@degree@C and this follows comparatively simple second-order kinetics. Here we report on STM studies of the Cl-covered Cu/Si(111) surfaces, following low temperature ( ~450@degree@C ) restructuring and at the onset of chlorosilane desorption at 600@degree@C. We will display evidence for the direct role of copper in the aggregation of Cl in compact Cl-containing regions during the high temperature chlorosilane desorption process. We will also discuss possible mechanisms of Cu-catalyzed desorption of chlorosilanes from the Si(111) surface.