Acquisition of object and temperature series in medium resolution off-axis electron holography with live drift correction

Abstract

Collecting and averaging large datasets is a common practice in transmission electron microscopy to improve the signal-to-noise ratio. Averaging data in off-axis electron holography requires automated tools capable of correcting both the drift of the interference fringes and the drift of the specimen. This can be achieved either off-line, by post-processing hologram series, or on-line, through real-time microscope control. For on-line correction, a previously suggested method involves independently adjusting the position of the intereference fringes and the sample by controlling the beam tilt coils and the stage during hologram acquisition. In this study, we have implemented this on-line correction method in a Thermo Fisher Scientific Titan transmission electron microscope. The microscope is equipped with a piezo-enhanced CompuStage for positioning the sample with high precision. However, the control of the piezo stage via direct scripting is not supported. We first describe a workaround to enable automated sample position correction. We then demonstrate the benefits of live, program-controlled acquisitions for serial experiments in medium resolution off-axis electron holography. Application examples include the automatic acquisition of an object series such as a transistor array and an in-situ temperature series of magnetic skyrmions.