Electron-impact-induced image contrast in FIM with organic image gases

Field-ion images of clean metal surfaces obtained by using organic image gases show bright spots rather than bright areas from surface regions of constant field strength. The origin of these spots has been investigated for cyclohexane and n-heptane as image gases and Pt/Ir tips prepared by field eva...

Full description

Saved in:
Bibliographic Details
Published in:Applied surface science 1994-03, Vol.76 (1-4), p.303-306
Main Authors: Schmidt, U., Röllgen, F.W.
Format: Article
Language:English
Subjects:
Electron, positron and ion microscopes, electron diffractometers and related techniques
Exact sciences and technology
Instruments, apparatus, components and techniques common to several branches of physics and astronomy
Physics
Scanning probe microscopes, components, and techniques
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Field-ion images of clean metal surfaces obtained by using organic image gases show bright spots rather than bright areas from surface regions of constant field strength. The origin of these spots has been investigated for cyclohexane and n-heptane as image gases and Pt/Ir tips prepared by field evaporation. It is shown that the spots arise from field ionization (FI) of molecules on surface deposits formed by electron-impact-induced fragmentation of adsorbed image-gas molecules. The impinging electrons are provided by FI of the image-gas molecules remote from the surface even at field strengths below those required for FI of the molecules adsorbed on the metal surface.
ISSN:0169-4332
1873-5584
DOI:10.1016/0169-4332(94)90359-X