Development of an Ultra Low Expansion Transmission Electron Microscopy in Situ Heating Holder

The primary experimental method used to determine the local internal structure of materials is that of transmission electron microscopy (TEM). If one also subjects the sample to an excursion in temperature during imaging at high resolution, one can watch the material processes involved in structural transformations. This allows direct and dynamic determination of the effects of materials processing on structure, and thus can provide critical insights to designing new materials with improved properties and performance. This approach not only permits deeper understanding of the basic physical processes involved, but also allows rapid exploration of a matrix of conditions and effects. However, current TEM heating holder designs that can accommodate a wide variety of specimens relies on substantially out-dated technologies, yielding significant problems with respect to drift / stability issues, expensive and time consuming maintenance and lack of precise and simple temperature control. Our motivation with this SBIR funded project is to develop a dramatically improved heating holder that is capable of delivering high-temperatures (1000C) to a sample, which is robust and as its most important feature has virtually no sample drift when the temperature of the sample is changed. In Phase I we build a prototype as proof of concept of the low drift mechanism. In Phase II we will optimize this prototype into a commercial product and make a double tilt version of the holder suited for all types of TEMs. This ultra-low drift TEM heating holder is expected to greatly aid researchers in exploiting hot-stage TEM, particularly during experiments that require imaging while increasing the temperature of the specimen, and are expected to lead to scientific advancements across multiple areas of research relevant to the DOE BES mission.