Paper AS-TuM9
XPS for Characterisation of Optical and Electronic Devices under Operation

Tuesday, October 29, 2013, 10:40 am, Room 204

A noncontact chemical and electrical measurement technique of XPS is performed to investigate a number of optical and electronic devices under operation. The main objective of the technique is to trace chemical and location specified surface potential variations as shifts of the XPS peak positions under operating conditions. Devices consisting of single and multi p-n junctions made out of Si. GaN and Graphene have been investigated under light illumination and/or under forward as well as reverse bias. The main advantage of the technique is its ability to assess element-specific surface electrical potentials of devices under operation based on the energy deviation of core level peaks in surface domains/structures. Detection of the variations in electrical potentials and especially their responses to the energy of the illuminating source under operation is also shown to be capable of detecting, locating, and identifying the chemical nature of structural and other types of defects.