Widest Temperature Range Cooling, Heating and Electrical Biasing In-Situ TEM Sample Holder

Cryogenic S/TEM sample holders have enabled the atomic resolution in-situ imaging of various quantum interfaces, topological insulators, and phase interactions in two-dimensional (2D) and one-dimensional (1D) materials. Quantum materials must be studied at cryogenic temperatures because many relevant properties in these quantum materials only manifest at specific low temperatures, necessitating low temperature ranges and precise control. Investigation of such quantum properties at the fundamental level has historically been challenging due to inadequate spatial and temporal resolution of characterization techniques as well as inadequate sample stability, while lack of biasing capability has limited the study of electrical responses in these materials systems.<br/><br/>Because battery materials are highly sensitive to electron beam damage at room temperature, cryogenic holders have also enabled imaging of battery interfaces and mapping of their complex chemical evolutions. With increasing demand for high temperature battery performance and battery material phase information across a wide range of temperatures from cryogenic to high temperature, temperature-controlled in-situ electrical biasing systems benefit from an expanded temperature range that meets microscope specifications for resolution and drift. The combination of cryogenic cooling and the chip-based experimental platform has enabled combined in-situ sample cooling, heating, and biasing experiments.<br/><br/>The core functionalities of an in-situ electrical biasing S/TEM holder that simultaneously allows electrical stimulus and high-resolution imaging of a sample in-situ across the full temperature range, from cryogenic up to high temperatures, are presented. The exceptionally stable holder experiences drift performance across the entire temperature range comparable to standard holders at room temperature.<br/><br/>Biasing was performed on a single nanowire system bridging the electrodes on a biasing chip at near-liquid nitrogen temperature (&lt;-170°C) to prevent electron beam damage. While applying constant current at cold temperature the voltage dropped with the growth of a dendrite layer on the nanowire's surface. With the modular heating controller, software, and chips, such experiments are extended to &gt;1000°C alongside electrical biasing of the sample. This enables studying the temperature dependence of chemical and microstructural evolution under electrical bias.<br/><br/>Between liquid nitrogen and room temperature, where on-chip resistance-calibrated temperature measurements become increasingly inaccurate, precise temperature control is enabled using a conventional resistance heater and miniature thermocouple at the sample in the TEM holder tip. The combination of temperature regimes allows batteries to be electrochemically cycled even beyond their full operational temperature range of of -40°C to 80°C and then returned to cryogenic temperature for imaging, without fear of electron beam damage or the need to change holders.<br/><br/>At intermediately cold temperatures, the two heating and temperature sensing methods can be combined for precisely controlled rapid heating experiments. This enables in-situ study of quantum nanomaterial synthesis, processing, and electrical response across a range of different temperatures in the low temperature regime.<br/><br/>The cryo-biasing TEM holder enables investigation of structure-property relationships in materials, specifically electronic properties, across the widest available temperature range, facilitating the development of the next generation of electronic, quantum, and energy storage materials devices.