Storing Matter: A new quantitative and sensitive analytical technique based on sputtering and collection of sample material

Abstract

The Storing Matter technique, which is a new analytical technique for both organic and inorganic materials, consists in decoupling the sputtering of the specimen from the subsequent analysis step. The surface of the specimen to be analysed is sputtered by means of an ion beam. The particles emitted under the impact of these primary ions are deposited at a sub-monolayer level on a dedicated collector under UHV conditions. It is only in a second step that the deposited matter is analysed in analytical instruments (mainly dynamic and static SIMS). Depositing the matter sputtered from different samples or from different layers of a sample on a same collector makes Storing Matter a powerful tool to circumvent the well-known matrix effect in SIMS. Moreover, enhanced secondary ion emission can be obtained in the different SIMS analysis modes as the collector surface and thus the matrix is chosen with respect to the elements to be analysed and the analysis mode (M +, M −, cationisation for organic information, etc.). In order to allow for the different steps of the Storing Matter technique to be performed under optimized conditions, a dedicated prototype instrument has been developed at SAM. This paper presents the Storing Matter technique and the dedicated prototype instrument with a special focus on the sputter-deposition process used in this new technique.