PAES

Positron annihilation induced Auger electron spectroscopy (PAES) is a newly developed
application for surface studies with high elemental selectivity and exceptional surface sensitivity. The instrument is operated by the Technische Universität München and is located at NEPOMUC.

In PAES, the emission of Auger electrons is initiated by positron-electron annihilation that leads to several major advantages compared with conventional electron induced AES. The main features are:

• topmost layer sensitivity
• no secpndary electron background at the Auger peaks
• non-destructive technique

PAES is part of the surface spectrometer (SuSpect) which also enables sample preparation in UHV conditions, conventaional AES and XPS. Examples for PAES studies are surfaces with sub-monolayers of foreign atoms, high resolution determination of Auger line shapes, element selective surface studies.