PNNL

Abstract

This paper is an update detailing further progress on research that was presented at the Joint Propulsion Conference in 2003. Low-energy sputtering yields of xenon-molybdenum (Xe+-Mo) systems were studied using both experimental techniques and models. The experimental measurements were obtained through Rutherford backscattering spectrometry (RBS) and mass-loss techniques. Both techniques produced similar data when they were applied simultaneously. Di_erential sputtering yields measured in each of the RBS experiments revealed an under-cosine angular distribution of sputtered atoms. The experimental results were surprising because the total sputtering yield was found to increase with decreasing ion energy between 80 and 60 eV. Modeling studies were performed using TRIM (The TRansport of Ions in Matter) computer simulations and semi-empirical models. Experimental and modeling results are compared with the sputtering yield data from other researchers. The comparison shows a lack of agreement among the experimental data and the models.