Methyl radical beam sources for ultra high vacuum applications

Abstract

AbstractMethyl radical beam sources for ultra high vacuum applications have been characterised using ionisation threshold mass spectrometry. Methane, ethane and acetone have been dissociated in a resistively heated carbon gas cracker cell. The effect of pressure on the methyl radicals formation has been studied independently of the precursor gas flow by changing the cell conductance. Methyl radical fluxes heavily depend on the pressure and the nature of precursor, ranging from 1 × 1015 cm–2 s–1 for a methane flow of 1 sccm up to 2 × 1016 cm–2 s–1 when acetone is used. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)