To obtain basic information on lithographic printing using aluminum plate etching, investigations have been made of the relationship between copper content in the aluminum and the pit morphologies that are electrolytically etched using nitric acid solutions. It was found that etched pit diameter decreased with increases in copper content up to maximun 0.1% Cu.
Aluminum thin films are widely used as conductors for integrated circuits, and with the need for finer paterning, it has become necessary to improve the reliability of aluminum thin films in the face of atmospheric humidity. This paper reports the properties of aluminum anodized in phosphate solutions with oxine Anodized films formed on aluminum were investigated by means of polarization behavior, impedance, electron microscopy, and infared and ICP plasma emission spectroscpoy Those films that were anodized in a solution of 0.1mol/L phosphate with 0.01mol/L oxine at a pH of around 3∼4 were most effective as corrosion inhibitors. These anodized films were found to consist of hydrated oxide films containing oxine
Using electrodialysis, ion permeation through porous alumina membranes wes examined below and above the isoelectric point, pH6. The pH-dependence of the amount of permeable anions (acidic dye and Cr2O72- ions) was found to agree with that of the ζ-potential. Since a porous alumina membranes in acidic solutions below pH6 have a positive charge, they will adsorbe such anions, which then migrate through the pores toward the anode. Both ζ-potential and permeability were observed to reach maxima at pH4. On the contrary, the behavior of basic dye cations was inverse to that of ζ-potential. Since at pH4, the membrane has the maximum positive charge basic dye cations cannot permeate due to electrostatic repulsion. At pH2 or 9, however, where the positive charge is less, slight permeation is possible.
The capacity of the etched aluminum foil used in electrolytic condensers is determined by its surface area A study was conducted on the initiation and growth of pits in high-purity aluminum foils during DC etching in hot hydrochloric acid, and pit structures after etching were observed by SEM images of resin replicas (1) The electrode potential during DC etching moved from a period of high potential to one of stability with a transition period of up to 50ms. Pits were initiated during the high-potential period, and pits with facets grew during the stability period (2) The high-potential and stability periods were reproduced by potentiostatic electrolysis, and the structures of the pits were examined It was found that pits were initiated at an electrode potential of about -400mV vs S.C.E, and pits with facets grew at an electrode potential of about -670mV vs. S C E An attempt was also made to represent the direction of pit growth using fractal dimensions
It was found that silvery-white, smooth electrodeposits were obtained by adding N-(3-Hydroxy-1-buthylidene)-p-sulfanilic acid (HBPSA) to silver methane sulfonate-potassium iodide baths. The bath composition and operating conditions most conductive to obtaining a smooth surface on the electroplated silver were 0.27mol/L of CH3SO3Ag, 3mol/L of KI, 2.06×10-2mol/L of HBPSA, with a pH of 5, bath temperature of 50°C, and current density of 0.5∼3A/dm2. Cathode current efficiency was over 95% at current densities between 1 and 3A/dm2, and throwing power was 30% at HBPSA 2.06×10-2mol/L The solderability and contact electric resistance of these silver deposits were approximately Similar to those from cyanide baths
The degradation of electrochromism in amorphous WO3-TiO2 films prepared by electron-beam deposition have been studied and the lifetime of the WO3-TiO2 films was found to be five times greater than that of the WO3 films. X-ray diffraction revealed that the crystal structure of the WO3-TiO2 films was still amorphous after the coloring and bleaching cycles, while a crystalline peak was observed in the amorphous WO3 films SIMS analysis revealed that lithium accumulated in the WO3 films, but not in the WO3-TiO2 films. The X-ray diffraction and XPS analysis revealed that the as-deposited WO3-TiO2 films were of an amorphous network structure based on the WO3 which has slightly shorter bonds length and that the WO3-TiO2 films are stable against the crystallization by annealing. From these results, the WO3-TiO2 films have a small number of defect bonds that act as trapping sites for lithium. We conclude that the prolonged lifetime of electrochromism in WO3-TiO2 films is the result of reduced accumulation of lithium in the films.
To accelerate the reduction rate of Fe3+ ion emitted from an insoluble anode in continuous iron plating, a new process which uses an anion exchange membrane inserted between catholyte and anolyte, and batch-type rotary drum reduction reactor has been developed. The superiority of the proposed process has been ascertained by laboratoryscale experiments. In the proposed process, Fe3+ concentration in anolyte exceeding 10g/L could be allowed without any plating problem for total iron ion concentration below 160g/L and cathode current density up to 100A/dm2 Under a high Fe3+ concentration in anolyte, it has been demonstrated that the reduction of Fe3+ to Fe2+ by metallic iron particles in the reactor is quite effective. The employed membrane electroplating made it possible to decrease the quantity of Fe3+-concentrated anolyte The maximum Fe3+ reduction rate of 32g/L Fe3+ anolyte was 4.6g/L/min, which was 46 times that obtained with 2g/L Fe3+ anolyte.