A high temperature vapor phase conformal coating for improving reliability of harsh environment electronics

This work describes the suitability of vapor phase polymerized Parylene HT ®on a variety of electronic components and devices through characterization of its thermal, electrical and other physical and chemical properties. Components of electronics, including integrated circuits, sensors, batteries, semiconductor devices, and other passive devices, are being packaged into smaller sizes with better performance and minimal weight. Overall system reliability and efficiency of the electronics depend on the quality of materials, packaging and how these devices are used. Parylenes, both as a coating and as a structural material, are known for their inertness, gas phase deposition, pinhole free application, adherence to metals, composites, plastics, elastomers, ceramics and excellent barrier properties. Parylenes commonly available to the market have been found to be useful up to 130^oC. The demand, however, is growing for a Parylene that is more stable at higher temperatures with excellent electrical properties. The data and evidence provided in this paper indicate that Parylene HT is suitable and capable of meeting the growing requirements of protection and reliability of advanced electronics up to 350^oC long-term and up to 450^oC for short-term exposures.