Jun S. Lee, Plastics Engineering; Carol M.F. Barry, Plastics Engineering and Joey Mead, Plastics Engineering
Electrical devices operate under harsh conditions and high temperatures, requiring coatings or hermetically sealed packaging to protect them. Hermetic packaging is not ideal due to their high cost and weight as well as low dielectric performance and poor reliability. Replacement of this hermetic packaging with environmental coatings, however, requires development of a new accelerated aging test. These tests are performed on electronic devices, with mathematical models used to calculate the product reliability and life span from the test data. For this work, failure sites and failure mechanisms of epoxy and polyimide IPC B-24 test coupons will be investigated with temperature-humidity-bias (THB) tests and highly accelerated stress tests (HAST). Peck's model will be used to fit the experimental data. In addition, saturated salt solutions at various humidities will be used to evaluate the effect of ionic contamination on the test coupons. Nanotechnology-based environmental coatings will be evaluated using the new test protocol.