Protective treatments for gold flashed finishes with a nickel substrate

Abstract

While precious metals such as gold or gold flashed palladium are preferred contact materials for connectors, cost considerations dictate the actual thickness used and hence the corrosion resistance. A method of preventing corrosion on contacts and providing connectors with uniform performance at a minimal cost is desirable. The authors were successful in developing a post-plating surface treatment that provides 0.1- mu m-thick gold contact finishes sufficient protection against 24-hr exposure to a standard mixed gas accelerated test. After the exposure, the contact resistance of 0.1- mu m gold on a nickel substrate is below 50 m Omega , while the same over a matte-finish nickel phosphorus alloy is below 5 m Omega .<>