Double-tilt in situ TEM holder with multiple electrical contacts and its application in MEMS-based mechanical testing of nanomaterials

Abstract

MEMS and other lab-on-a-chip systems are emerging as attractive alternatives to carry out experiments in situ the electron microscope. However, several electrical connections are usually required for operating these setups. Such connectivity is challenging inside the limited space of the TEM side-entry holder. Here, we design, implement and demonstrate a double-tilt TEM holder with capabilities for up to 9 electrical connections, operating in a high-resolution TEM. We describe the operating principle of the tilting and connection mechanisms and the physical implementation of the holder. To demonstrate the holder capabilities, we calibrate the tilting action, which has limits of ±15°, and establish the insulation resistance of the electronics to be 36GΩ, appropriate for measurements of currents down to the nano-amp (nA) regime. Furthermore, we demonstrate tensile testing of silver nanowires using a previously developed MEMS device for mechanical testing, using the implemented holder as the platform for electronic operation and sensing. The implemented holder can potentially have broad application to other areas where MEMS or electrically-actuated setups are used to carry out in situ TEM experiments.

Methods for Calibration of Specimen Temperature During In Situ Transmission Electron Microscopy Experiments

“…1b) or a heat-conductive thin membrane. Several other MEMS chip designs are available (Hattar et al, 2004; Bernal et al, 2015; Yang et al, 2019).…”

“…There are also commercially available chip-based heating-biasing holders using the concept of a heater spiral (Figure 1b) or a heat conductive thin membrane. Several other MEMS chip designs are available (Hattar et al, 2004, Bernal et al, 2015, Yang et al, 2019.…”

Atomistic perspective on in situ nanomechanics

“…The recent advance in TEM characterization techniques, such as the aberrationcorrected TEM 141 and ultrafast camera for electron detection and data recording 142 , are expected to further push the limit of the in situ experimental mechanics down to the subangstrom and millisecond scales in the near future, thereby providing new opportunities of studying the ultrafast defect dynamics. Double-tilt straining holder needs to be developed for enabling the flexible atomic-scale imaging 143 . Moreover, the development of MEMS device and environmental TEM enables us to conduct the nanomechanical testing at controlled temperatures 144,145 and environmental conditions 146,147 .…”

In situ TEM studies of micron‐sized all‐solid‐state fluoride ion batteries: Preparation, prospects, and challenges

“…In situ TEM studies require complex sample geometries to, on one hand, fulfill the stringent requirements for reliable TEM analysis and, on the other hand, to provide the right environment for reliable observation of chemical reactions to correlate the structural changes with the actual operating conditions. A variety of TEM sample holders have been developed over the last couple years to approach an environment closely mimicking the actual operation conditions of batteries (Bernal et al, ; Eswara Moorthy et al, ; Miller et al, ; Uhlig et al, ) inside a TEM. Despite this, the preparation of an actual battery system and developing or employing the right imaging conditions, to prevent preparation and beam induced artifacts still remains a challenge.…”