29 Sep 2026
Dr Robin Scales visits Switzerland for Synchrotron Experiment
PXCT Technique at cSAXS Beamline on 4H-SiC Superjunctions
Photograph of Carys Davies, Robin Scales, and Huaiyu Chen, from left to right.
Dr Robin Scales visited the Swiss Light Source's cSAXS beamline (link) and successfully performed Ptychographic X-ray Computed Tomography (PXCT) on micro-pillars of 4H-SiC superjunctions (proposal 20260342).
PXCT is a powerful synchrotron-based technique that allows one to surpass the resolution limits of X-ray lenses by utilising and reconstructing the sample from diffraction patterns. In addition to higher spatial-resolution (~4 nm record doi) it extracts out the components of phase and amplitude for a sample in 3D, where the former is related to electron density.
Extracting the electron density is 3D is very helpful to analyse the nano-scale voids that can form within 4H-SiC superjunctions for high power semiconductor devices, due to their weak scattering and their small size.
Dr Scales has already began a draft from these results and anticipates one or more papers to be generated from this work!
Acknowledgements:
Carys Davies (Dept. of Materials, University of Oxford) who travelled with Robin to Switzerland to help with the experiment alongside beamline scientist Dr Huaiyu Chen (link). The experiment and proposal was aided by senior scientists Dr Mirko Holler (link) and Dr Ana Diaz (link).
Dr Gareth Hughes (DCCEM, University of Oxford), Prof Patrick Salter (University of Oxford), and Dr Armin Wagner (Diamond Light Source) who all greatly aided in the development and execution of the sample manufacturing.
Prof Dong (Lilly) Liu (link) and REWIRE-IKC for the funding and support.
Dr Vishal Shah (link) and Dr Gerard Colston at the University of Warwick for the 4H-SiC sample we extracted the micro-pillars from and for their continued support.
Images
Photograph of the PSI West containing the Swiss Light Source.
False-colour SEM image of a finalised micro-pillar that was analysed with PXCT.
Photograph at the cSAXS beamline of Carys Davies, Robin Scales, and Huaiyu Chen, from left to right.
Photograph of Dr Robin Scales outside the cSAXS beamline.
