NEAR ATMOSPHERIC PRESSURE X-RAY PHOTOELECTRON SPECTROSCOPY(NAP-XPS)

The NAP-XPS represents a revolution in the field, allowing for XPS characterization of a sample in   a gaseous environment. This is achieved by containing the sample in a high pressure cell which is   only open to the analyzer via a small aperture. A series of pumping stages after this aperture quickly   reduce the pressure back down to high vacuum and limits the distance the electrons have to travel   through a high pressure of gas. By placing the surface of the sample very close to this aperture, the   area under analysis can be in a high pressure of gas whilst also allowing a useable fraction of the   emitted photoelectrons to escape and reach the detector.