Sputter-Induced Cross-Contaminations in Analytical AES and XPS Instrumentation: Utilization of the effect for the In-situ Deposition of Ultrathin Functional Layers

TL;DR

This paper investigates how sputter-induced cross-contaminations in AES and XPS instruments can be exploited to deposit ultrathin functional layers in situ, improving measurement accuracy and enabling new sample modifications.

Contribution

It reveals the mechanism of reflective sputtering and demonstrates its use for in-situ ultrathin layer deposition in AES and XPS analysis.

Findings

Cross contaminations occur during sputter depth profiling.

Reflective sputtering can deposit ultrathin layers on samples.

Utilization of this effect improves measurement techniques.

Abstract

Cross contaminations are observed on sample surfaces by AES and XPS, if multiple samples are mounted on one sample holder and a neighbouring sample was sputter depth profiled. During sputter depth profiling sputtered material is deposited on inner surfaces of the instrument. In a secondary sputter process, which is due to species leaving the primary sputter target with higher kinetic energy, the previously deposited material is transported from the inner surfaces to the other samples mounted on the sample holder. This Reflective Sputtering is utilized to deposit ultra-thin layers on sample surfaces for XPS binding energy referencing purpose and to build up ultra-thin conductive layers to enable AES measurements on insulating samples.