Contact Us

Dr Debbie Hammond d.hammond@sheffield.ac.uk

Prof. Graham Leggett
graham.leggett@shef.ac.uk

Chemistry Department
University of Sheffield
Dainton Building
Brook Hill
Sheffield
S3 7HF

XPS Instrument Chamber

Axis Ultra DLD X-ray photoelectron spectroscopy provides quantitative chemical state information on the upper 1-10 nm of a surface.

Our Axis Ultra DLD is equipped with a monochromated Al-kα X-ray source, a Minibeam III allowing in situ sample cleaning and a spherical mirror analyser capable of mapping with a spatial resolution below 3 µm.

XPS: X-ray photoelectron spectroscopy

Basic Principle: An X-ray beam is focussed onto a surface resulting in the ejection of electrons with kinetic energies characteristic of the atoms and bonding environments they originate from.

Survey spectrum of a self assembled monolayer

Survey Spectra

The number of electrons is plotted as a function of binding energy to produce survey spectra.

These spectra show the elemental composition of a surface.

C 1s spectrum of a self assembled monolayer

High Resolution Spectra

The binding energy of a photoelectron reflects the bonding environment it was emitted from.

Accurate measurement of peak positions after deconvolution of high resolution spectra provides quantitative chemical state information.

Plasma polymer patterned onto a silicon substrateMetabolites spotted onto a silicon substrate

Species Mapping can be performed on 200 - 800 µm2 areas with a spatial resolution below 3 µm. Small spot analysis can be carried out on areas as small as 15 µm to determine the elemental composition at specific regions of the surface.

LEFT: A 400 µm2 image of a plasma polymer patterned onto a silicon substrate (Si 2p red, C-O green).
RIGHT: An 800 µm2 image of metabolites spotted onto a silicon substrate (Si 2p green, N 1s red).