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Ronny Kleinhempel Gunar Kaune Matthias Herrmann Hartmut Kupfer Walter Hoyer Frank Richter 《Mikrochimica acta》2006,156(1-2):61-67
Indium tin oxide (ITO) thin films were deposited by mid frequency pulsed dual magnetron sputtering using a metallic alloy
target with 10 wt.% tin in an atmosphere of argon and oxygen. The aim of the work was to study the interdependence of structural,
electrical and optical properties of ITO films deposited in the reactive and transition target mode, respectively. The deposition
rate in the transition mode exceeds the deposition rate in the reactive mode by a factor of six, a maximum value of 100 nm·m min−1 could be achieved. This corresponds to a static deposition rate of 200 nm min−1. The lowest electrical resistivity of 1.1·10−3 Ω cm was measured at samples deposited in the high oxygen flow range in the transition mode. The samples show a good transparency
in the visible range corresponding to extinction coefficients being below 10−2. X-ray diffraction was used to characterise crystalline structure as well as film stress. ITO films prepared in the transition
mode show a slightly preferred orientation in (211) direction, whereas films deposited in the reactive mode are strongly (222)
oriented. Compared to undoped In2O3 all samples have an enlarged lattice. The lattice strain perpendicular to the surface is about 0.8% and 2.0% for films grown
in the transition and the reactive mode, respectively. Deposition in the transition mode introduces a biaxial film stress
in the range of −300 MPa, while stress in reactive mode samples is −1500 MPa. 相似文献
10.
Rearrangement of Tertiary Allyl Alcohols Induced by Bromination: The Effect of a Fluorine Substituent on the Rate and the Outcome of the Reaction The allyl alcohol bearing a methyl and a t-butyl group at the hydroxylated position was found to undergo a rearrangement when treated with bromine (or N-bromosuccinimide) in an aqueous medium and to afford a product mixture containing two regioisomeric ketones and one oxirane. Introduction of an additional methyl group or a fluorine atom at the non-terminal olefinic center led to a more selective discrimination between potential migratory groups. As the result of an exclusive t-butyl shift only one product, a ketone, was formed in both cases. Whereas the reaction rate was only slightly affected by the additional methyl group, it was substantially decreased by the fluorine atom. 相似文献