A Fast and Implantation-Free Sample Production Method for Large Scale Electron-Transparent Metallic Samples Destined for MEMS-Based In Situ S/TEM Experiments

Abstract

Microelectromechanical systems (MEMS) are currently supporting ground-breaking basic research in materials science and metallurgy as they allow in situ experiments on materials at the nanoscale within electron microscopes in a wide variety of different conditions such as extreme materials dynamics under ultrafast heating and quenching rates as well as in complex electro-chemical environments. Electron-transparent sample preparation for MEMS e-chips remains a challenge for this technology as the existing methodologies can introduce contaminants, thus disrupting the experiments and the analysis of results. Herein we introduce a methodology for simple and fast electron-transparent sample preparation for MEMS e-chips without significant contamination. The quality of the samples as well as their performance during a MEMS e-chip experiment in situ within an electron microscope are evaluated during a heat treatment of a crossover AlMgZn(Cu) alloy.

In situ transmission electron microscopy as a toolbox for the emerging science of nanometallurgy

“…The drawing illustrates the sequence of steps necessary to obtain a viable sample. The first step is based on the methodology presented by Tunes et al , 27 in which a jet-electropolished electron-transparent sample can be sectioned and transferred onto a MEMS chip. For later alloying, a nanomaterial-diluted solution is pipetted upon the latter, which is the substrate and will act as a matrix material.…”

“…The sample is then transferred to the MEMS chip sensor membrane with the help of a fine electrostatic bristle used as a manipulator. 27 SiN-coated e-chips from Protochips for vacuum applications were used as MEMS chips. Two solutions supplied by Sigma-Aldrich, one containing Cu nanowires, serial number MKCL4540, and the other containing Au nanoparticles, serial number MKCK9621, were used as the carrier substance to be used as alloying elements.…”

“…25,26 The current study aims to introduce a new nanometallurgical method for exploring alloying and phase transformations using nanomaterials in transmission electron microscopy (TEM). This lab-on-a-chip approach, which uses the TEM as a chemical reactor for metals, is based on a previously described method by Tunes et al 27 where a material can be deposited on a micro-electromechanical systems (MEMS) chip without the need for focused ion beam (FIB) preparation. The experiments focus on the Al-Cu and Al-Au systems since both have well-established literature on their thermodynamic properties and precipitation sequences.…”

Radiation-resistant aluminium alloy for space missions in the extreme environment of the solar system

“…In situ TEM annealing and ion irradiation In situ TEM annealing was carried out to investigate the microstructural response and stability of the UFG Al-based alloy in addition to evaluate its precipitation behavior. For these experiments, a Protochips FUSION MEMS chip-based holder in a Thermo Fisher Talos F200X S/TEM was used followed by a sample preparation procedure described in the literature (47).…”

Focused Ion Beam Sample Preparation for In Situ Thermal and Electrical Transmission Electron Microscopy

“…Lastly, the procedure should be applicable to a wide range of materials. There exist some procedures on how to create similar samples, but we wish to expand the range of possible approaches (Duchamp et al, 2014; Vijayan et al, 2017; Tunes et al, 2021).…”