USE OF PARALLEL IMAGING XPS TO PERFORM RAPID ANALYSIS OF POLYMER SURFACES WITH SPATIAL-RESOLUTION LESS-THAN-5-MU

X-ray photoelectron spectroscopy (XPS or ESCA) is one of the most common surface analytical techniques available. It has proved over many years to be invaluable in the analysis of elemental and chemical species on surfaces. The recent developments of this technique towards spatially resolved XPS information has made it possible to use XPS for analysis of very small features on insulating materials such as polymer surfaces, on which other high spatial resolution techniques such as Auger electron spectroscopy (AES) suffer difficulties generated by, for example severe sample charging effects. The new VG ESCALAB 220iXL from VG Scientific (Fisons Instruments) uses parallel imaging together with a magnetic objective lens to provide chemical images of better than 5 mum spatial resolution in just a few minutes. Subsequent point analysis using selected small-area XPS can be performed on any feature in the images down to 7 mum resolution. In combination with this unique parallel imaging facility, a new high-intensity x-ray monochromator source makes fast chemical state imaging at high spatial resolution relatively routine. Several examples of the analysis of polymer surfaces will be shown, including chemical state imaging of the C 1s, C-C, and C-O bonding states from 15 mum features.