Shozo Mizumoto

Preparation and Electrical Resistance Characteristics of Electroless Copper-Nickel Alloy Deposits

SummaryStudies have been made of an electroless copper-nickel-phosphorus alloy from a citrate complex bath using hypophosphite as reducing agent and electroless copper-nickel binary alloy from a triethanolamine complex bath using formaldehyde as reducing agent. With an increase in copper content of alloy, the specific resistance of deposit decreased. The TCR of copper-nickel-phosphorus alloy increased remarkably because of the crystallization of Ni3P after heat treatment. But the increase in TCR of copper-nickel binary alloy was moderate and not so striking as for the phosphorus containing alloy.

Photochemical formation of palladium patterns on surface-modified polyimide resin

A simplified method for forming a palladium circuit pattern on polyimide resin substrate was proposed. The carboxyl group, as a cation exchange group, was formed on the polyimide resin surface by a potassium hydroxide treatment. Palladium(II) ion was then adsorbed onto the surface modified polyimide resin by ion exchange. Ultraviolet irradiation of this palladium(II) ion absorbed resin with sodium formate coated on its surface resulted in the formation of a palladium thin film. Irradiation through a metal-on-quartz mask onto the modified polyimide resin surface photoreduced the palladium ion into metallic palladium circuit patterns easily without using a plating resist.

Electroless palladium plating from an ethylenediamine complex bath using phosphite as a reducing agent

SUMMARYElectroless palladium plating was investigated from palladium-ethylenediamine complex solutions containing sodium phosphite as a reducing agent.The deposition process proceeded autocatalytically as with hypophosphite, but the phosphorus content in the deposits was much lower.From the experimental results on solderability and electric contact resistance, it was suggested that electroless palladium plating could be utilized as an alternative to gold plating on electrical contacts and to solder or the preflux coat for ensuring good solderability.

Preparation of Cu-Ni Film Resistors with Low Resistivity and Low TCR

SUMMARY Thin film resistors with low TCR and low electric resistivity were prepared from phosphorus free Cu-Ni alloy obtained by electroless and electrolytic deposition with heat treatment at low temperature.

Physico-chemical analysis on chemical bonding at adhesion interface between rubber and Pd alloy

Abstract Some spectroscopic analyses were carried out on the adhesive interface layers formed by cure-adhesion of natural rubber to electroless Pd and/or Pd–P alloys. The transmission electron microscopy revealed some clear images of the adhesion layer just at the interface between rubber and electroless-plating films of Pd and/or Pd–P alloys. The content ratio of Pd/S analyzed by energy dispersive X-ray spectroscopy changed gradually along the depth at the rubber–metal interface layer for Pd alloy, but was kept almost constant irrespective of depth for Pd–P alloy.

Direct patterning of silver circuit using surface-modification and UV irradiation on polyimide resin

SUMMARY A simplified method is proposed for the formation of a silver circuit pattern on a polyimide resin substrate through modification of the resin surface followed by adsorption of silver(l) ion and UV photoreduction to form patterns. The amide bond and carboxyl group, as a cation exchange group, were formed on the polyimide resin surface by a potassium hydroxide treatment. UV irradiation of the adsorbed silver(I) ion results in the formation of a silver thin film. Silver circuit patterns are easily formed on the modified polyimide resin substrates without using a plating resist by use of a metal-on-quart: mask

Electroplating by Jet Flow Method of Electrolyte

Copper or nickel was electroplated by using a jet flow device, in which the electrolyte flowed through a nozzle in high speed jet dashing perpendicularly against the cathode specimen, and then flowed away. As the results of experiments, it was found that the maximum available current density was 100amp./dm2 or more at a jet flow rate of 200cm/sec.. The flow of electrolyte and other factors in practice were discussed.