The EBSD spatial resolution of a Timepix-based detector in a tilt-free geometry

•A Timepix-based EBSD detection system with a small form factor and zero readout noise is shown to collect high quality EBSPs in a tilt-free geometry.•The horizontal sample and parallel detector sensor setup enables safer specimen movements for large area analyses and significant improvements in the longitudinal spatial resolution of the technique.•The measured physical spatial resolution is consistently higher using a pattern quality method as compared to a normalised cross correlation method.•The best resolution for molybdenum is measured as 22 nm and 31 nm for the pattern quality and normalised cross correlation methods, respectively. Performing EBSD with a horizontal sample and a parallel EBSD detector sensor, enables safer specimen movements for data collection of large specimen areas and improves the longitudinal spatial resolution. The collection of electron backscattering patterns (EBSPs) at normal incidence to the electron beam has been revisited via the use of a direct electron detection (DED) sensor. In this article we present a fully operational DED EBSD detection system in this geometry, referred to as the tilt-free geometry. A well-defined Σ=3[101]{121} twin boundary in a Molybdenum bicrystal was used to measure the physical spatial resolution of the EBSD detector in this tilt-free geometry. In this study, two separate methods for estimating the spatial resolution of EBSD, one based on a pattern quality metric and the other on a normalised cross correlation coefficient were used. The spatial resolution was determined at accelerating voltages of 8 kV, 10 kV, 12 kV, 15 kV and 20 kV ranging from ~22−38 nm using the pattern quality method and ~31−46 nm using the normalised cross correlation method.