Author: Prabjit Singh Company: IBM Corporation Date Published: 9/27/2015
Abstract: The power consumption by information technology equipment keeps rising as data center proliferation continues unabated. In order to contain the rising computing costs, data center administrators are resorting to cost cutting measures such as not tightly controlling the temperature and humidity levels and in many cases resorting to air side economizers with the associated risk of introducing particulate and gaseous contaminations into their data centers. Conformal coating is a proven means of protecting electronics from polluted and high humidity environments. Conformal coatings find wide use in military and commercial applications. This paper will report on details of testing conformal coatings by applying the coatings on thin silver films and measuring the corrosion rates of the underlying silver films in a flowers of sulfur chamber. The corrosion rates of the silver thin films were determined by measuring the resistance changes of the silver thin films by the 4-point probe method. It was confirmed that silicone conformal coatings increases the rate of corrosive attack by sulfur-bearing gases leading to reduced corrosion protection of the underlying metallization. Silicone coatings were found to act as a “sponges” that increased the rate of corrosion of the underlying silver. The characterization results of commercially available alternatives to silicone coatings, such as fluoropolymer based coatings, will be presented.