SPECTROMICROSCOPY AND CHEMICAL IMAGING BY LATERALLY-RESOLVED ESCA

Brief details of the operation of the ESCA200 instrument are presented as an example of the Scienta/Seiko family of laterally-resolved spect roscopes. This is followed by an investigation of charging on such ins ulators as single crystal sodium chloride (NaCl) or oxide and nitride thin layers on silicon, In addition local charging effects on conducti ve samples of carbon nanotubes and quasi-monodimensional (TaSe4)(2)I c ompounds are presented, It is shown that charging (causing an apparent shift in core level energies) can be area dependent, that it can be t ime variant and that the charging can alter the signal to noise charac teristics of certain photoelectron peaks, Furthermore it is shown that some of the large area photoelectron spectroscopy results may have to be reconsidered in the light of the small area results. A discussion of the origin of the charging is included. The power of our laterally- resolved spectroscope is shown in practical results obtained from such technologically based samples as CsI photosensitive surfaces and the reactions occurring on the surface of semiconducting gas sensors. In a ddition tribochemical effects between Cu and Ni with alumina have been studied and results are presented. (C) 1997 Elsevier Science B.V.