Electron, Ion, and Electromagnetic Radiation Spectroscopies

These techniques are generally able to provide quantitative as well as qualitative analysis of the specimen surface, and a number of them may be used in combination to maximize the amount of information obtained. 

X-ray photoelectron spectroscopy is frequently applied in the fields of catalysis and polymer technology. It has poor spatial resolution, and is generally limited to homogenous samples. Radiation sensitive materials are more appropriate for XPS analysis, as the X-ray beam is less damaging to the specimen surface than the electron beam used in AES, partly due to the lower flux densities that are used. 

Depth profiling may be conducted on insulating materials, and XPS can perform thickness measurements on organic films such a lubricants on magnetic media. It is capable of measuring surface contamination by both inorganic and organic materials on a wide variety of substrates. 

Auger electron spectroscopy is preferred over XPS where high spatial resolution is required, although the samples need to be conducting and tolerant to damage from the electron beam. Many oxides readily decompose under electron radiation, and this may give rise to difficulty in spectral interpretation, and this has restricted the application of AES in the field of catalysis. 

In its basic form, a broad-focussed electron beam probe provides compositional information on a relatively large area (— 1 mm2), to a depth of the order of 1 nm. To obtain information about the variation of composition with depth, controlled 

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