Paper EW-TuL5
State of the Art in XPS

Tuesday, November 10, 2009, 1:20 pm, Room Exhibit Hall 1

Modern XPS instruments such as the Axis range from Kratos Analytical offer a variety of analytical capabilities extending beyond simple chemical characterisation of the upmost layers of a material surface. Advances in ion gun technology, chemical imaging resolution, instrument spectroscopic performance and data processing have made analysis faster, data more accurate and the previously impossible possible. XPS is becoming more wide spread with new users from fields such as photovoltaics, biocompatibility, pharmaceuticals and nano-science enjoying the benefits of surface analysis.

More specifically; improvements in ion gun technology have meant low energy monatomic sources can give better interface quality for multi-layer inorganic materials. The development of polyatomic ion sources has made XPS depth profiling of organic materials feasible. XPS imaging has developed into a technique to quantitatively characterise surface inhomogeneity and the application of multivariate data analysis techniques has reduced acquisition times while improving information content. Angle resolved XPS has benefited from new interpretation routines via the application of maximum entropy analysis methods to extract meaningful, non destructive, concentration profiles over the first few nanometres.

This presentation aspires to give an overview of the state of the art in XPS driven surface analysis by presenting examples and case studies from a number of important application areas ranging from thin film photovoltaics to bio-compatibility. Examples where hardware and software advances have helped the analyst will be given for techniques such as auto quantification, XPS depth profiling, angle resolved XPS, chemical state imaging, work function determination and electronic structure characterisation.