300 keVTransmission electron microscope (TEM)

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We apply for a state-of-the-art analytical high-resolution scanning / transmission electron microscope, for the nanoscale structural and chemical characterization of beam sensitive and high-performance materials. It is required for the investigation of elementary mechanisms which govern the formation and evolution of nano and microstructures in functional and structural materials. A sound understanding of these processes characterizes materials research in different fields including chemistry, physics, nano technology and engineering materials science. The different research communities focus on different materials with specific properties. But all research efforts have in common that atomic scale features (position, chemical nature and electronic properties of atoms) govern the formation and evolution of nano- and microstructure which in turn define the material properties on the macro scale. In crystalline materials point defects (vacancies and impurities), linear defects (dislocations), planar defects (internal and external interfaces) and 3D defects (such as pores, inclusions and nanoparticles) are important. These defects are viewed as the critical elements of nano- and microstructures. The new instrument will give a scientific boost to KIT material projects (running, approved and planned), in particular to collaborative research activities (clusters of excellence, collaborative research centers, graduate school) where there is a need to apply high level analytical electron microscopy. The new AHR-S/TEM is needed to analyze nano- and microstructures. In its high-resolution mode, it will allow to access atomic level information (atom positions, electronic structure of atoms) as well as local chemistry on the nano scale. The new microscope will be able to characterize all materials, also beam sensitive ones. State of the art AHR-S/TEMs are equipped with a field emission gun (which provides high energy electrons with little scatter in electron energy) and a monochromator (which allows to filter electron energies). They possess corrector devices (which allow to overcome spherical aberrations ) and analytical spectrometers (which allow for efficient local chemical and electronic property assessment). They feature a sensitive and fast detection hardware which allows to monitor high-speed material evolution processes upon applying external stimuli in structural engineering materials, chemical catalysts and in all kinds of electron beam sensitive materials. Today’s AHR-S/TEMs represent integrated systems which allow to directly observe dynamic processes on the nanoscale (in situ methods) and to determine crystallographic textures (nano and micro scale). Most importantly, the AHR-S/TEMs must run with a software environment, which allows to effectively combine sequences of analysis steps, to digitally organize procedures and document data and metadata and to operate the instrument under remote control.