Optimization of ARXPS for various applications

Motivation and results

In modern technology thin films are shrinking more and more to a few nanometer thickness. Analytical investigations of such thin films using the traditional sputter depth profiling have restrictions due to physical effects especially for very thin films. Angle-resolved X-ray photoelectron spectroscopy (ARXPS) is widely accepted as a useful tool for non-destructive in-depth analysis of near surface regions. We made a series of ARXPS investigation at different materials systems and discussed which kind of qualitative and quantitative information can be derived from ARXPS measurements in conjunction with appropriate mathematical modelling. For that purpose we have developed a flexible computer algorithm for data interpretation. We also discussed the limitations from contamination, roughness or preparation-induced damage and the generally strongly limited information content of ARXPS.

Outlook

The ARXPS data interpretation procedures will be refined applying better minimum search strategies for approximation of measurement and modeling. In combination with results from computer simulation we look for limitations arising from complicated surface structures and measuring inaccuracies.

References

M. Kozlowska, R. Reiche, S. Oswald, H. Vinzelberg, R.Hübner, K. Wetzig: Quantitative ARXPS investigation of systems at ultrathin aluminium oxide layers, Surf. Interface Anal. 36 [13] (2004) 1600-1608. (doi:10.1002/sia.1988)

S. Oswald, R. Reiche, M. Zier, S. Baunack, K. Wetzig: Depth profile and interface analysis in the nm-range, Appl. Surf. Sci. 252 [1] (2005) 3-10. (doi:10.1016/j.apsusc.2005.01.102)

S. Oswald, M. Zier, R. Reiche, K. Wetzig: Angle-resolved XPS: A critical evaluation for various applications, Surf. Interface Anal. 38 [4] (2006) 590-594. (doi:10.1002/sia.2216)

M. Zier S. Oswald, R. Reiche, K. Wetzig: Non-destructive depth profile analysis using synchrotron radiation excited XPS, Microchimica Acta 156 [1-2] (2007) 99-101. (doi:10.1007/s00604-006-0615-9)