X-ray Photoelectron Spectroscopy
X-ray photoelectron spectroscopy allows the analysis of the atomic composition and of chemical bonding states of a sample in the immediate vicinity of the surface.
The image shows the XPS setup of the division Plasma Edge and Wall at IPP Garching. A look through the window of the ultra high vacuum device shows a tungsten sample being analysed. According to its naming – XPS is the acronym for X-ray photoelectron spectroscopy – the device is equipped with several X-ray sources (in the left part of the image) and an electron detector. The analysis method of X-ray photoelectron spectroscopy allows the determination of the chemical composition of the topmost atomic layers. It is therefore optimally suited to investigate surface modifications caused by contact of the surface with a hot plasma. The top right part of the images shows one of the ion sources. They create beams of charged particles which allow to simulate the contact of the sample surface with a plasma under well-defined conditions.