Differential charging in x-ray photoelectron spectroscopy: a nuisance or a useful tool?

Date
2003
Editor(s)
Advisor
Supervisor
Co-Advisor
Co-Supervisor
Instructor
Source Title
Analytical Chemistry
Print ISSN
0003-2700
Electronic ISSN
Publisher
American Chemical Society
Volume
75
Issue
24
Pages
7026 - 7029
Language
English
Journal Title
Journal ISSN
Volume Title
Series
Abstract

We apply a negative bias to the sample while recording an XPS spectrum to enhance differential (positive) charging. The enhanced differential charging is due to the repulsion of stray electrons from the sample, which normally cause partial neutralization of the poorly conducting samples or regions accumulating positive charging, as a consequence of the photoelectron emission. This enhanced differential charging (obtained by negative biasing) is shown to have the ability to separate otherwise overlapping peaks of PDMS layer from that of the SiO2/Si substrate. Each layer experiences different charging that can be used to derive information related to dielectric properties of the layers, proximity of the atoms within composite multilayers, or both. Hence, differential charging in XPS, which is usually considered as a nuisance, is turned into a useful tool for extracting additional information from nanometer-size surface structures.

Course
Other identifiers
Book Title
Citation
Published Version (Please cite this version)