Complex Thermal Chemistry of Vinyltrimethylsilane on Si(100)-2×1

• Published in: The journal of physical chemistry. B Vol. 109; no. 17; pp. 8462 - 8468
• Main Authors: Pirolli, Laurent, Teplyakov, Andrew V
• Format: Journal Article
• Language: English
• Published: American Chemical Society 05.05.2005
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp0467853

The surface chemistry of vinyltrimethylsilane (VTMS) on Si(100)-2×1 has been investigated using multiple internal reflection−Fourier transform infrared spectroscopy, Auger electron spectroscopy, and thermal desorption mass spectrometry. Molecular adsorption of VTMS at submonolayer coverages is dominating at cryogenic temperatures (100 K). Upon adsorption at room temperature, chemical reaction involving rehybridization of the double bond in VTMS occurs. Further annealing induces several reactions:  molecular desorption from a monolayer by 400 K, formation and desorption of propylene by 500 K, decomposition leading to the release of silicon-containing products around 800 K, and, finally, surface decomposition leading to the production of silicon carbide and the release of hydrogen as H2 at 800 K. This chemistry is markedly different from the previously reported behavior of VTMS on Si(111)-7×7 surfaces resulting in 100% conversion to silicon carbide. Thus, some information about the surface intermediates of the VTMS reaction with silicon surfaces can be deduced.