Copper Plating

Characterization of Thick Film of Copper Electrodeposited for Cryogenic Applications

“…Compared to other metals, copper is one of the most used in the deposition processes. 2 Copper is an excellent substrate, when is mechanically polished, and its electrical conductivity, being second only to silver, makes it an excellent and inexpensive coating for printed circuit boards. 2 Furthermore it is suitable for covering surface defects like holes or splinters and it is used as an excellent buffer layer between the substrates and the subsequent deposits.…”

“…2 Copper is an excellent substrate, when is mechanically polished, and its electrical conductivity, being second only to silver, makes it an excellent and inexpensive coating for printed circuit boards. 2 Furthermore it is suitable for covering surface defects like holes or splinters and it is used as an excellent buffer layer between the substrates and the subsequent deposits. The large use of Cu in electrical industry is mainly due to the possibility to deposit this material with different techniques.…”

“…A thick film of copper on a brass support is often used for obtaining special current leads, with selected balancing at cryogenic temperatures between electrical resistance and total thermal conductivity between room temperature and cryogenic bath. 1,2,3 In this way it is possible to supply the required high currents, also minimizing the heat absorbed by the external environment and by the instrumentation from the cryogenic line. The use of brass, as internal support of a copper conductor, offers a series of advantages such as: a good mechanical strength, the opportunity to realize the interface brass-copper without an intermediate material (no surfactant is required), a good workability, a good electrical conductivity at room temperature, as well as a limited heat transfer at cryogenic temperatures.…”

“…moderately alkaz E-mail: davoli@roma2.infn.it line copper plating (solutions based pyrophosphate). 2,6 Specifically, the acid baths of copper are simple solutions containing copper ions, sulfate ions and fluoroborate with the corresponding acids and others additives. The acid baths of copper are, therefore, easier to control and stabilize with the time and at the contrary of the chemical baths based on alkali cyanide and non-cyanide, the composition of chemical baths acids are not very critical.…”

“…The acid baths of copper are, therefore, easier to control and stabilize with the time and at the contrary of the chemical baths based on alkali cyanide and non-cyanide, the composition of chemical baths acids are not very critical. 2,7 Last, but not least the cost is relatively low. The efficiencies of their cathodes and anodes are high (close or equal to 100%), and can tolerate high current densities.…”