Imaging XPS

Useful for identifying small features, understanding the distribution surface chemistry or examining the thickness variation of ultra-thin coatings.

Types of imaging

Parallel acquisition

Parallel acquisition simultaneously images the entire field of view without scanning voltages applied to any spectrometer component. Parallel imaging provides  a set of quantitative images that can be acquired within minutes. This method is faster than the mapping method, typically achieving an image resolution of <3 μm. Subsequent data processing produces a relative atomic concentration image that can be used to define the elemental and chemical composition as a function of position.

Serial acquisition (mapping)

Serial acquisition of images is based on a two-dimensional, rectangular array of small-area XPS analyses. This method enables measurements of the distribution of elements or chemical states. Serial acquisition is generally slower than parallel acquisition but can collect a range of energies at each pixel compared with collecting only a single energy for parallel acquisition. Using this method, the analysis position is fixed and the specimen surface is moved with respect to this position.



XPS imaging is useful in understanding:

  • elemental and chemical distribution over a surface
  • examination of thickness variations on ultra-thin coatings
  • determination of contamination limits.

All systems at Harwell, Cardiff and UCL are capable of performing XPS imaging.