The CPP (combined polymerization and pyrolysis) preparation route, in its enhanced liquid-precursor-based version, was combined with consecutive soft milling. For studies of temperature- and size-dependent structural changes occurring in ferroelectric lead titanate, this combined route yields a nanopowder series covering the relevant particle-size region at target quality. This material basis enables consistent SEM, TEM, XRD, Raman, EPR and dielectric measurements, which furnish a comprehensive picture of the cooperation between temperature rise and size reduction to eliminate tetragonality and concomitant ferroelectricity. Our previous original EPR studies on nanosized barium titanate are now extended to the lead titanate case. Furthermore, as compared to the pertinent literature standard, the materials basis is extended to powder samples of smaller mean particle sizes, comprising the critical size at which a PbTiO3 particle undergoes a transition into cubic paraelectric phase. Thus, the size-driven phase transition can be observed in a direct way (at 7 nm, which compares to 40 nm for BaTiO3), and the EPR data suggest a much less spacious gradient shell at the particle surfaces (thickness ≈ 2 nm) than in previous analogous investigations on BaTiO3 (15 nm).

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Shape memory alloy (SMA) thin films are used as actuator materials in MEMS due to their unique properties. Binary thin films with a composition close to Ni50Ti50 are well-established materials, whereas ternaries like NiTiCu, NiTiPd, NiTiHf are less studied. Furthermore, new alloys are being developed which show a magnetic shape memory effect, e.g. Ni2MnGa. For the optimization of known, and the development of new, SMA thin films, a fast and reliable characterization technology is needed, which rapidly identifies the transformation temperatures (i.e. martensite and austenite start and finish temperatures) for a range of material compositions deposited on a whole wafer. In this paper, automated temperature-dependent resistance measurements are discussed as a means which yields the thermal hysteresis of the investigated thin films. Results of monitoring the uniformity of shape memory film depositions on the wafer level, as well as results on the use of this method as a tool for screening for new SMA films by characterization of materials libraries are reported.

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