Paper AS-ThP1
Wide-Range Parallel XPS Imaging for Feature Identification

Thursday, October 31, 2013, 6:00 pm, Room Hall B

X-ray Photoelectron Spectroscopy (XPS) is a well-established technique for surface-sensitive measurements of the elemental and chemical-state composition of a material. Naturally, there has been a drive to allow imaging methods with XPS, so that chemical distributions can be obtained with high spatial resolution.

One such method, parallel XPS imaging, allows for the simultaneous acquisition of the entire image at a single energy, with high spatial resolution. Conventionally, acquiring such images in small energy steps across a photoelectron peak of interest yields a spectroscopic image, where each pixel contains a spectrum.

Typically, such spectroscopic images are acquired across a single peak region, such as C1s. This minimizes acquisition time, and generates more manageable data sets that are conceptually similar to region spectra in conventional XPS. On a modern XPS instrument, it is possible to acquire a full-range spectroscopic image, where each pixel contains a survey spectrum. This is rarely done, mainly due to acquisition times, and the fact that a point survey spectrum from the imaged area will usually give the elemental composition without need for survey images. However, there are advantages to the method, namely the ability to retrospectively generate spectra from arbitrary parts of the imaged area, to identify composition at any location.

In this presentation, the extension of the parallel XPS imaging technique to wider energy ranges will be discussed, showing how in some situations the use of wide-range spectroscopic imaging can provide information that is difficult or impossible to gain using single-point spectroscopy or region spectroscopic imaging analyses.