The utilisation of higher excitation energies facilitating an increase in the electron information depth.
HarwellXPS is pleased to faciliate access to the world’s first high-throughput lab-based HAXPES spectrometer (Scienta Omicron) at the Sir Henry Royce Institute for Advanced Materials at the University of Manchester.
Using a high energy X-ray source (gallium metal jet, Ga Kα hν = 9250 eV, Excillum) bespoke monochromator and high KE electron energy analyser (EW4000), HAXPES is finally available outside of a synchrotron.
Sampling depths are extended from 3-10 nm for XPS up to 30-60 nm for HAXPES (element and core level dependent). The EW4000 analyser operates in an angle-resolved mode, meaning that angle-resolved XPS, reducing the sampling depth towards the surface, is captured in one measurement, enabling non-destructive depth profiling from the surface into the bulk. Inelastic background modelling (Tougaard analysis using QUASES software, www.quases.com) enables detection of deeply buried layers up to 100s nm below the surface, extending sampling depths up to potentially twenty times the inelastic mean free path of electrons.
The HAXPES instrument includes heating/cooling facilities, there is a linked preparation chamber, and standard XPS using Al Kα is also available on the instrument. A vacuum suitcase can also be used to transport samples under vacuum for prevention of oxidation
Access higher energy orbitals
With excitation sources of up to 9 keV, we are able to access deeper lying core orbitals.
Understand deep buried structure
Increased electron escape depths permit access to buried interfaces and layers.
bulk-sensitive photoemission spectroscopy
non-destructive depth-profile of device stacks
angle-resolved measurements at same time
non-destructive depth-profiling of thin layer interfaceos
oxide or overlayer thickness measurements
layer-ordering of layers on a flat substrate.
This dedicated HAXPES facility is located at the University of Manchester. Applications can be made via HarwellXPS.
The Harwell hub also has access to monochromatic Ag La radation, offering approximately double the information depth of Al radiation