Chemical sputtering by impact of excited molecules

¹  Physics Division, Oak Ridge National Laboratory - P.O. Box 2008, Oak Ridge, TN 37831-6372, USA
²  Department of Chemistry, Clemson University - Clemson, SC 29634, USA

Corresponding author: krsticp@ornl.gov

Received: 17 August 2006
Accepted: 6 December 2006

Abstract

We study chemical sputtering of deuterated amorphous carbon surfaces by atoms, vibrationally excited , and dissociating molecules, in a range of impact energies, . We analyze the role of the internal state, i.e. the vibrationally excited and dissociating states of the neutral molecules resulting from above-surface neutralization of impacting molecular ions in typical sputtering experiments. The sputtering yields are shown to considerably increase with the internal vibrational energy at the lowest impact energies. By comparison of calculated and measured yields we draw conclusions regarding the possible mechanisms for neutralization.