HARSH ENVIRONMENT IMPACT ON RESISTOR RELIABILITY

The electronics industry has observed an increase in the incidents of corrosion failures in data centers located in harsh industrial environments and in geographies with atmospheres high in sulfur-bearing gaseous contamination. Several failing signatures have been observed, including creep corrosion of copper plating on printed circuit boards and the corrosion of resistor terminals. Resistor terminal corrosion results in electrical opens as the corrosion product, silver sulfide, builds up and consumes the terminal metallurgy. The reaction to these corrosion failures has included three key efforts. The first has been to investigate the source of the sulfur-bearing gases and to take actions to reduce the exposure of the electronics to these corrosive gases. The second has been to increase the robustness of the components to sulfur-bearing gases either through a change in the construction of the component or applying gas-impervious barriers. And the third has been to develop a laboratory accelerated corrosion technique to predict and compare the life of the components in harsh field conditions. This paper will discuss work in each of these three areas. Significant efforts have been undertaken to assess the environmental conditions in numerous data centers and recommend steps to improve the air quality. Manufacturers of components have developed alternative materials and/or constructions to improve the robustness of components when exposed to high sulfur environments. Mitigation techniques to apply a barrier such as a conformal coating have been developed and evaluated for effectiveness. And laboratory evaluation techniques have been explored to assess and rank component robustness for use in high sulfur environments