The application of electron spectroscopy to surface studies

Abstract

The application of three branches of electron spectroscopy to surface studies, with particular emphasis on submonolayer chemisorption systems, is reviewed. The three branches are x-ray photoelectron spectroscopy (XPS), vacuum uv photoelectron spectroscopy (UPS), and Auger electron spectroscopy (AES). Each technique is considered from the standpoints of (i) the depth of material probes, (ii) signal strength, (iii) quantitative aspects, (iv) chemical information obtainable, and (v) induced surface effects. Since UPS does not provide an atomic identification, it is best used in conjunction with either of the other two techniques. In general, XPS will provide more chemical information, more quantitatively, than AES, though analysis times are slower. However, since the three techniques have advantages and disadvantages which may depend on the system studied and the object of the study, a combination of the three is usually preferable and can be experimentally achieved using only one electron energy analyzer.