Metal particulate-containing conformal coatings for improved IT hardware reliability in harsh environments

Abstract

A method to overcome IT hardware corrosion-related failures in geographies with highly concentrated atmospheric pollution is presented. Metal particulate was incorporated into a standard silicone conformal coating to form composite materials in which the metal particulate acts as a sacrificial material to react with elemental sulfur. Metal particulates (copper and silver) were chosen based on their strong propensity to corrode in sulfur-rich environments. Through absorption of sulfur into silicone composites, the metal particulate is able to react to form either copper sulfide or silver sulfide before reaching the underlying metallic architectures, thus preventing failures. This approach resulted in up to a ~123% life improvement of the coated component over that of a standard silicone conformal coating. In addition, this approach has shown that the sacrificial material can slow the rate of metal sulfide formation at the metallic interface of thick-film surface mount resistors. The metal particulate-containing conformal coatings developed here overcome many limitations brought about by the use of non-silicone conformal coatings, potentially leading to its incorporation into IT hardware to prevent metallic corrosion of components in harsh environments.