Imaging the Reaction of H2O Molecules on Isolated Surface Dangling Bond Pairs
張展源1*, 林登松1
1物理學系, 國立清華大學, 新竹市, Taiwan
* Presenter:張展源,
It is known that dissociative adsorption pathways of gas molecules on semiconductor surfaces depends not only on the numbers of neighboring dangling bonds available, but also on their configurations. A clean surface is full of dangling bonds in all kinds of reactive site configurations. It is thus desirable to visualize the adsorption with atomic resolution on the surfaces where dangling bonds are few and isolated. Herein we prepare isolated dangling bond pairs on the Si(100) surface as well-defined chemically-reactive sites for chemisorption of water molecules. Each of the dangling bond pairs acts as a designed reactant configuration that are surrounded by passivated chlorine-termination. Scanning tunneling microscopy reveals four major surface reaction pathways upon H2O gas exposure.
The reaction product, H-Si-O-Si-H species is observed with the highest probability.

Keywords: water, dangling bond