Here is the abstract you requested from the HITEN_2017 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Development of a High Temperature Protective Coating to Enable Organic Printed Circuit Boards to Operate at Higher Temperatures|
|Keywords: Reliability, Substrates, Coatings|
|Reliable operation of electronics at higher temperatures requires a combination of performance improvements in components, interconnects and substrates. Ceramic based substrate options can be costly, heavy and prone to mechanical damage. Printed circuit board (PCB) options are restricted to lower working temperatures of the organic resins and degradation of their conductive tracks. A collaborative research programme between project partners Microsemi (MSL), the National Physical Laboratory (NPL) and Gwent Electronic Materials (GEM), has successfully developed innovative materials specifically designed to offer protection to organic PCBs and interconnect allowing them to operate at higher temperatures or for longer durations. Currently, the operation of electronic assemblies at higher temperatures is limited by the ability of copper clad printed circuit boards (PCBs) to maintain circuit integrity. The Tamessa project has developed a coating material which when applied to printed circuit assemblies (PCAs) makes them more suitable for operating at temperatures above 200 oC. This paper summarises the work undertaken by the authors to develop and better understand the performance enhancements produced by these materials. The project brought together a materials supplier (GEM), an end-user (MSL) and a technology research organisation (NPL) to jointly develop, test and implement the solution based on silicone coating materials. This paper focuses on the testing and materials evaluation undertaken at the NPL to determine the long term performance of these alternative materials in harsh environments. Details of the electrical performance of component and PCB interconnects between the substrates and components during the test regimes are given as well as the degradation mechanisms experienced in unprotected PCAs. The manufacturing process is outlined including details of the test vehicles utilised. Details of test methodology used and comparable results for coated and uncoated systems will be given. The results show a significant improvement of mean-time-to failure (MTBF) for coated PCAs and PCBs compared to uncoated samples. The primary performance improvement is shown to be reduction in the oxidation rate of copper in both the inner and outer layers of copper tracking in the multilayer structures.|
|MArtin Wickham, Senior Research Scientist
National Physical Laboratory