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Register a new userThe annealing induced extraordinary properties of SI based ZNO film grown by RF sputtering
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Publication date
2007
fields
Informatics Engineering
and research's language is
English
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Pb(Zr0.52Ti0.48)O3 (PZT) thin films were in situ deposited by pulsed laser deposition (PLD) on Pt/Ti/SiO2/Si substrates using a template layer derived by sol-gel method. A 0.1-$mu$m-thick PZT layer with (111) or (100)-preferred orientation was first deposited onto Pt/Ti/SiO2/Si substrates using the sol-gel method, and than a PZT layer with thickness of 1$mu$m was in situ deposited by PLD on the above-mentioned PZT layer. The crystalline phases and the preferred orientations of the PZT films were investigated by X-ray diffraction analysis. Surface and cross-sectional morphologies were observed by scanning electron microscopy and transmission electron microscopy. The electrical properties of the films were evaluated by measuring their P-E hysteresis loops and dielectric constants. The preferred orientation of the films can be controlled using the template layer derived by the sol-gel method. The deposition temperature required to obtain the perovskite phase in this process is approximately 460 degrees C, and is significantly lower than that in the case of direct film deposition by PLD on the Pt/Ti/SiO2/Si substrates. Keywords: lead zirconate titanate (PZT), thin film, sol-gel method, laser ablation, electrical properties
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We have investigated the correlation between structural and transport properties in sputtered $beta$-FeSe films grown onto SrTiO$_3$ (100). The growth parameters, such as substrate temperature and thickness, have been varied in order to explore different regimes. In the limit of textured thick films, we found promising features like an enhanced $T_{rm c}sim12,$K, a relatively high $H_{rm c2}$ and a low anisotropy. By performing magnetoresistance and Hall coefficient measurements, we investigate the influence of the disorder associated with the textured morphology on some features attributed to subtle details of the multi-band electronic structure of $beta$-FeSe. Regarding the superconductor-insulator transition (SIT) induced by reducing the thickness, we found a non-trivial evolution of the structural properties and morphology associated with a strained initial growth and the coalescence of grains. Finally, we discuss the origin of the insulating behavior in high-quality stressed epitaxial thin films. We found that a lattice distortion, described by the Poissons coefficient associated with the lattice parameters textit{a} and textit{c}, may play a key role.
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