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Transmission electron microscopy (TEM) characterization of nickel contacts to bulk bismuth tellurium selenide [Bi 2 (Te,Se) 3 ] is reported. Samples were prepared in a dual column focused ion beam/scanning electron microscope (FIB/SEM) system using a lift-out technique, with ion beam energy and exposure times carefully optimized to minimize sample damage. Diffusion of Ni into Bi 2 (Te,Se) 3 was observed and the formation of a nickel telluride (NiTe) interfacial region confirmed after heat treatment at 200• C. Selected area diffraction patterns provided evidence of a modified bismuth telluride-like structure at the interface, identified by analytical electron microscopy to be composed of Ni and Bi 2 (Te,Se) 3 .

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In this work a characterization system for high energy-density capacitors is described and demonstrated. Capacitors are being designed using thin-film technology in an attempt to achieve higher energy-density levels by operating the devices at a high voltage. These devices are fabricated from layers of 100 nm aluminum and a layer of polyvinylidene fluoride-hexafluoropropylene on a polyethylene naphthalate plastic substrate. The devices have been designed to store electrical charge at up to 200 V. Characterizations of these devices focus on the measurement of capacitance vs bias voltage and temperature, equivalent series resistance, and charge/discharge cycles. For the purpose of the characterization of these capacitors, an electronic charge/discharge interface was designed and tested.