Adsorption geometry of furan on Si(100)-2 x 1

Abstract

We have investigated adsorption of furan on Si(100) at room temperature using high resolution photoemission spectroscopy (PES) and near edge X-ray absorption fine structure (NEXAFS) in the partial electron yield (PEY) mode. The Si 2p, C 1s, O 1s spectra of furan on Si(100) show that furan is chemisorbed on Si(100)-2 x 1 through [4 + 2] cycloaddition. NEXAFS has been conducted to characterize the adsorption geometry of furan on Si(100). Since the pi(*) orbital of C = C bond showed a good angle dependence in carbon K-edge NEXAFS spectra, the angle 28 +/- 2 degrees determined from NEXAFS spectra appears to deviate from a theoretical value of 19 degrees for the [4 + 2] cycloaddition by 9 degrees, mostly due to the intrinsic defects on the Si(100)-2 x 1 substrate surface. (C) 2007 Elsevier B.V. All rights reserved.