122297-32-9Relevant academic research and scientific papers
Direct writing of copper film patterns by laser-induced decomposition of copper acetate
Harish,Kumar,Prabhakar
, p. 2903 - 2904 (1988)
Direct writing of patterns is being widely attempted in the field of microelectronic circuit/device manufacture. In this communication we report a technique for both single line and large area deposition of copper through decomposition of copper acetate, (CH3COO)2Cu, on alumina substrates. Nd:YAG laser known for its reliability and low maintenance cost as compared to excimer and other gas lasers is used. This technique offers an attractive and economical alternative for manufacture of thin film microcircuits.
Systematic investigation of current efficiency during brass deposition from a pyrophosphate electrolyte using RDE, RCE, and QCM
Johannsen,Page,Roy
, p. 3691 - 3702 (2000)
The pyrophosphate electrolyte has been used for brass deposition as a replacement for cyanide electrolytes. However, there is considerable confusion about the current efficiency of brass deposition from this electrolyte. This study uses a rotating disc electrode (RDE), a rotating cylinder electrode (RCE) and a quartz crystal microbalance (QCM) to systematically determine the current efficiency of copper, zinc, and brass deposition from a pyrophosphate electrolyte. Electrodeposition of brass on RCE and QCM show that the current efficiency for copper, zinc as well as brass is well below 100%. Simultaneous measurement of current and frequency at a QCM showed that pyrophosphate is adsorbed at the electrode surface during copper reduction. However, when zinc is present in the solution, pyrophosphate adsorption is blocked.
Salt-Free Reduction of Nonprecious Transition-Metal Compounds: Generation of Amorphous Ni Nanoparticles for Catalytic C-C Bond Formation
Yurino, Taiga,Ueda, Yohei,Shimizu, Yoshiki,Tanaka, Shinji,Nishiyama, Haruka,Tsurugi, Hayato,Sato, Kazuhiko,Mashima, Kazushi
, p. 14437 - 14441 (2015)
A salt-free procedure for the generation of a wide variety of metal(0) particles, including Fe, Co, Ni, and Cu, was achieved using 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (1), which reduced the corresponding metal precursors under mild conditions. Notably, Ni particles formed in situ from the treatment of Ni(acac)2 (acac=acetylacetonate) with 1 in toluene exhibited significant catalytic activity for reductive C-C bond-forming reactions of aryl halides in the presence of excess amounts of 1. By examination of high-magnification transmission electron microscopy images and electron diffraction patterns, we concluded that amorphous Ni nanoparticles (Ni aNPs) were essential for the high catalytic activity.
Oxygen non-stoichiometry in Ru-1212 and Ru-1222 magnetosuperconductors
Matvejeff,Awana,Jang,Liu,Yamauchi,Karppinen
, p. 87 - 92 (2003)
We report here the results of thermogravimetric (TG) analysis on the oxygen non-stoichiometry of RuSr2GdCu2O 8-δ (Ru-1212) and RuSr2(Gd0.75Ce 0.25)2Cu2O10-δ (Ru-1222) samples. With TG measurements carried out in O2 and Ar atmospheres it is found that the oxygen content in Ru-1212 remains less affected upon various annealings, while for Ru-1222 the wider-range oxygen-content tuning is possible. When heated in H2/Ar atmosphere the both phases release oxygen upon breaking down to mixtures of metals (Ru and Cu) and simple oxides (CeO2, Gd2O3, and SrO) in two distinct steps around 300 and 450 °C. This reductive decomposition reaction carried out in a thermobalance is utilized in precise oxygen content determination for these phases. It is found that the 100-atm O2-annealed Ru-1212 sample is nearly stoichiometric, while the similarly treated Ru-1222 sample is clearly oxygen deficient. X-ray absorption near-edge structure (XANES) spectroscopy is applied to estimate the valence of Ru in the samples. In spite of the fact that the Ru-1212 phase was shown to possess less oxygen-deficient RuO 2-δ layer, the valence of Ru as probed with XANES is found to be lower in Ru-1212 than in Ru-1222.
INFLUENCE OF THE ANION ON COPPER ELECTROCRYSTALLIZATION.
Carneval,de Cusminsky
, p. 1215 - 1221 (1981)
Structural studies of copper electrodepositions from pyrophosphate, chloride, cyanide, and citrate solutions were carried out on highly polished (001) copper surfaces at a wide range of current densities under galvanostatic conditions. The study was performed by means of x-ray diffraction. The deposition morphology was observed with a scanning electron microscope. Correlation among internal structure, surface morphology, solution composition, and plating conditions were examined. The results were compared with previous studies from sulfate solutions. Expitaxial growth was observed in the early stage of deposition. The effect of the anion on the change from single crystalline to polycrystalline growth at further stage is analyzed.
Hydrazine reduction of metal ions to porous submicro-structures of Ag, Pd, Cu, Ni, and Bi
Wang, Yue,Shi, Yong-Fang,Chen, Yu-Biao,Wu, Li-Ming
, p. 19 - 26 (2012)
Porous submicro-structures of Ag, Pd, Cu, Ni, and Bi with high surface area have been prepared by the reduction of hydrazine in glycerol-ethanol solution at room temperature or 120-180 °C. Phase purity, morphology, and specific surface area have been characterized. The reactions probably undergo three different mechanisms: simple reduction for Ag and Pd, coordination-then- reduction for Cu and Ni, and hydrolysis-then-reduction for Bi. The reductant hydrazine also plays an important role to the formation of the porous submicro-structure. The reaction temperature influences the size of the constituent particles and the overall architecture of the submicro-structure so as to influence the surface area value. The as-prepared porous metals have shown the second largest surface area ever reported, which are smaller than those made by the reduction of NaBH4, but larger than those made by hard or soft template methods.
Electrodeposition and photoelectrochemistry of Cu2O in aqueous solutions
De Jongh,Vanmaekelbergh,Kelly
, p. 187 - 200 (1999)
Well-defined crystalline Cu2O was electrodeposited on TFO from basic Cu(II)-lactate solutions. Experimental conditions, especially the temperature and pH of the deposition solution, had a strong influence on the deposition kinetics and the morphology of the formed layers. The photo-electrochemical properties of the Cu2O were investigated. A composite material was made by electrodepositing the p-type Cu2O inside a nanoporous n-type TiO2 electrode. by Oldenbourg Wissenschaftsverlag, Muenchen.
New developments in the field of energy transfer by means of monomode microwaves for various oxides and hydroxides
Gasgnier, M.,Loupy, A.,Petit, A.,Jullien, H.
, p. 165 - 172 (1994)
By means of a 'focused' microwave oven (monomode system) it is possible to carry out chemical syntheses within very short times. The use of a new magnetron with higher performance experimental conditions has allowed us to observe phenomena which have not previously been recorded. For instance, it is possible within very short treatment times to form copper metal from Cu2O, TiO2 rutile from TiO2 anatase, PbO from Pb3O4 and the V6O13 and V2O5 higher oxides from V2O3. Finally, it is possible to turn white powders such as SnO2, TiO2 and η-Al2O3 and green powders such as Cr2O3 incandescent red. Several hypotheses will be put forward to try to explain this phenomenon. The temperature measurement is also discussed as a function of the dielectric constant of the materials.
Properties of Cu-Ni ferrite nanopowders prepared by coprecipitation method with ultrasound irradiation
Doh,Kim,Lee,Oh
, p. 1889 - 1892 (2004)
Cu-Ni ferrite(Cu1-xNixFe2O4) nanopowders were synthesized by coprecipitation method with ultrasound irradiation. They were composed of a spinel phase having a spherical shape with the grain size of 20 - 40 nm. The specific surface area of the nanopowders showed a tendency of decreasing with increasing Ni content (x). The maximum value of saturation magnetization was 73.5 emu/g at x = 0.5. The reflection loss was higher than 10 dB in the frequency range from 2.5 GHz to 5.5 GHz. The maximum reflection loss of 25 dB was observed at x = 0.5. Thermogravimetric analysis of the Cu1-xNixFe2O4) nanopowders for both H2 reduction and CO2 decomposition reaction was carried out with Cahn vacuum electrobalance system. The maximum CO2 decomposition occurred in the Cu0.5Ni 0.5Fe2O4) nanopowder.
The effect of the Cu2+/Cu+ step on copper electrocrystallization in acid noncomplexing electrolytes
Vazquez-Arenas, Jorge,Vazquez, Gerardo,Melndez, Angel M.,Gonzalez, Ignacio
, p. D473-D481 (2007)
The effect of different electrolytes (ClO4-, NO3-, and SO4 2- at 1 M) at pH 3 on the kinetics, growth type, and morphology of copper electrodeposition on glassy carbon was studied. The concentration was 0.1 M Cu2+ in all of the solutions employed. In cyclic voltammetry, a larger reduction peak was obtained in the nitrate electrolyte, in comparison with the other two media. This higher current has been associated with the catalytic reduction of nitrate ions on recently deposited metallic copper. This effect was confirmed in the potential-step analysis. Despite the fact that Cu+ is not thermodynamically stable in these three solutions, the reduction step Cu2+ Cu+ has been considered as an electron-transfer reaction. The anion type has a direct effect on this electron-transfer reaction and consequently, on the electrocrystallization process; sulfates provoke the most important current decrease associated with the Cu2+ Cu+ step and also strongly influence the nuclei formation, while the nitrate ions accelerate the Cu2+ Cu+ step. The scanning electron microscopy images obtained for copper deposits after different deposition times corroborate the type of copper nucleation predicted by the electrochemical techniques.
