Wucher, Andreas, Tian, Hua and Winograd, Nicholas (2014) A Mixed Cluster Ion Beam to Enhance the Ionization Efficiency in Molecular Secondary Ion Mass Spectrometry. Rapid Communications in Mass Spectrometry, 28 (4). pp. 396-400. ISSN 1097-0231

Abstract

Chemical modification of a 20 keV Ar gas cluster ion source with 1-2% CH4 is shown to increase the intensity of desorbed molecular ions in secondary ion mass spectrometry experiments by a factor of ~4 relative to the pure Ar cluster. From depth profiling experiments, the results are shown to arise from an increase in the ionization efficiency of the sputtered molecules rather than any change in the sputtering yield of neutral species. Tuning of the chemistry of mixed clusters is suggested as a general approach to maximizing the ionization probability by up to 2 orders of magnitude.

Item Type:	Article
Date Deposited:	28 Apr 2016 23:45
Last Modified:	28 Apr 2016 23:45
URI:	https://oak.novartis.com/id/eprint/11148