Measuring scattering distributions in scanning helium microscopy

C J Hatchwell; M Bergin; B Carr; M G Barr; A Fahy; P C Dastoor

doi:10.1016/j.ultramic.2024.113951

Measuring scattering distributions in scanning helium microscopy

Ultramicroscopy. 2024 Jun:260:113951. doi: 10.1016/j.ultramic.2024.113951. Epub 2024 Mar 7.

Authors

C J Hatchwell¹, M Bergin², B Carr³, M G Barr¹, A Fahy¹, P C Dastoor¹

Affiliations

¹ Centre for Organic Electronics, University of Newcastle, Callaghan, NSW 2308, Australia.
² Centre for Organic Electronics, University of Newcastle, Callaghan, NSW 2308, Australia. Electronic address: matthew.bergin@newcastle.edu.au.
³ Department of Physics, Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK.

PMID: 38471412
DOI: 10.1016/j.ultramic.2024.113951

Abstract

A scanning helium microscope typically utilises a thermal energy helium atom beam, with an energy and wavelength (¡100meV, ∼0.05 nm) particularly sensitive to surface structure. An angular detector stage for a scanning helium microscope is presented that facilitates the in-situ measurement of scattering distributions from a sample. We begin by demonstrating typical elastic and inelastic scattering from ordered surfaces. We then go on to show the role of topography in diffuse scattering from disordered surfaces, observing deviations from simple cosine scattering. In total, these studies demonstrate the wealth of information that is encoded into the scattering distributions obtained with the technique.

Keywords: Atom scattering; Scanning helium microscopy; Scattering distribution.