Adsorption of halogenated organic molecules and photo-induced construction of a covalently bonded second organic layer on silicon surfaces

Abstract

HREELS, XPS and the DFT calculations were applied to study the adsorption of halogenated organic molecules, as well as the photo-induced construction of a covalently bonded secondary organic layer on silicon surfaces.

The results demonstrate that molecular templates on silicon surfaces with unique structures and properties can be manipulated in the controllable reaction pathways upon chemisorption of halogenated molecules on silicon surfaces. Fluoroacetonitrile adsorbs on Si(100)-2?1 via a C=N [2+2]-like cycloaddition, while bromoacetonitrile undergoes the ene-like reaction on Si(100)-2?1. Chloroacetonitrile reacts with Si(100)-2?1 via the combination of C=N [2+2]-like cycloaddition and ene-like reaction. 3-chloro-1-propanol binds onto the Si(100)-2?1 and Si(111)-7?7 surfaces via the O-H group dissociation.

Based on the understanding the surface chemistry of halogenated molecules on silicon surfaces, the photochemistry of 3-chloro-1-propanol and photo-induced secondary bonded 3-chloro-1-propanol layer on Si(100)-2?1 were investigated. In addition, the photo-reactions of d3-acetonitrile and benzonitrile with 3-chloro-1-propanol modified Si(111)-7?7 surface were systematically studied.