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Nitrogenated tetrahedral amorphous carbon (N:ta-C) films prepared by the filtered cathodic vacuum arc technique were studied by x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, spectroscopic ellipsometry, ultraviolet photoelectron spectroscopy and temperature dependent resistance measurement. As the nitrogen flow rate varies from 0 to 20 sccm, the nitrogen content in the deposited film increases from 0 to 4.6 at. %. Curve fitting of the C 1s and N 1s XPS spectra shows that the C–C sp3 fraction decreases with an increase in nitrogen content and that the nitrogen atoms are mainly bonded in sp2 C–N bonds. The pure ta-C film has a work function of 4.35 eV and the N:ta-C films have a value around 4.55 eV. With an increase in nitrogen flow rate, the intensity ratio of the D peak to the G peak, ID/IG increases monotonously from 0.44 to 1.25 and the G peak width decreases from 220 to 199 cm−1. The Tauc optical band gap decreases from 2.2 to 1.8 eV.

Early stages of Sn-doped In 2 O 3 (ITO) "lm deposition on room temperature (RT) acrylic-coated polycarbonate (PC) substrates using dc magnetron sputtering were investigated, by comparing them with those on RT soda-lime glasses. The microstructure and electrical properties of the "lms were analyzed as they grew from 1 to 330 nm. The ITO/glass had conductivity when the thickness was larger than 4 nm, whereas the ITO/PC had conductivity at a thickness larger than 14 nm, and became constant at about 21 nm. According to a result obtained by AFM, average roughness (R ! ) of the ITO/glass surface showed remarkable change with increasing thickness re#ecting initial nucleation, coalescence and continuous "lm growth processes, i.e. Volmer}Weber-type initial growth. Whereas, in the case of ITO/PC, R ! was almost constant, except for the peak caused by substrate damage at a thickness smaller than 4 nm. ( 2000 Elsevier Science Ltd. All rights reserved.

We have been developing polymer actuators that have high performance and also have high productivity. The production process of this actuator is simple and employing common instrument. The displacement at 30seconds after applying voltage 2.0V was about 5mm for 15mm sample. The displacement is in proportion to the period of applying constant current. The output force is over 4mN at 2.0V. We also clarify a bending mechanism of our polymer actuator include bend back motion. The differences in size and in moving speed between cations and anions play a major role in bending mechanism. We also estimate the size and moving speed of each type of ions. These values are consistent with the measured displacement result.