Inherently EMI Shielding Conformal Coatings

Smart munitions, unmanned vehicles, and the total integration of air, ground, and sea forces has generated a significant need for advanced electronics. The drive for compact electrical systems, reduced weight, and increased heat dissipation has taxed theElectrical Engineer. A prominent area requiring technology advancement is treatment of Printed Wire Boards (PWB) to provide environmental and EMI protection. Traditionally, polymer based conformal coatings are used to seal and protect PWB's fromenvironmental exposure with metallic enclosures added to provide EMI shielding. An industry target is to enable the conformal coating to provide the EMI protection as well. The maturation of carbon nanotube technology is enabling such a multifunctionalcoating. In Phase I, Eikos demonstrated the use of carbon nanotube additives to achieve EMI shielding of 40dB in a standard conformal coating resin. The resulting multifunctional coating is entitled Nanoshield¿. The small amounts of carbon nanotubesrequired for Nanoshield¿ have minimal effects on base coating properties and cost. Nanoshield¿ has demonstrated compatibility with commercially available conformal coatings and application equipment. Eikos with Northrop Grumman support proposes a phase IIprogram to demonstrate a multifunctional coating and implementation plan to reduce mass, volume, and cost of advanced electronic systems. Imparting EMI shielding to conformal coating eliminates the need for metallic enclosures integrated into PWB. Thiswill significantly reduce the size and weight of electronic systems. Achieving this goal will result in smaller computer envelopes, more payload capability of aircraft, and more effective cooling of densely packed electronic systems.