Surface Decomposition Kinetics of Organosilane Precursors to Silicon Carbide

Abstract

ABSTRACTReactive molecular beam scattering techniques with mass spectrometric detection have been used to characterize the kinetics and mechanism of the decomposition of two 1,3-disilacyclobutane precursors to SiC on the Si(100) surface to yield SiC and gas-phase byproducts. Both compounds adsorb and desorb without dissociation at ambient temperature. Reaction probability increases with increasing surface temperature to a maximum exceeding 0.8 at 1100 K. Both compounds yield large quantities of gas-phase intermediates, while only one produces a significant yield of SiC in the initial collision. In situ and ex situ analysis of the SiC film indicate that it is stoichiometric SiC. A combination of mass spectrometric detection with time of flight analysis of surface reaction products permits formulation of a reaction scheme involving a multistep surface decomposition sequence.