Searching for appropriate humidity accelerated migration reliability tests methods

摘要

Lifetime estimation is one of today's frequently used reliability testing tool. There are standardized test methods, mathematical apparatus and failure acceleration models for predicting failure rate of electronic components, circuit modules or equipment. Do the widespread used models give a precise description for all kind of failure mechanisms? Can they define the acceleration factor of any test, and the accelerated lifetime of any test vehicles? In connection with open surface migration tests (when the test circuit samples are not covered by any protective or packaging material) two climatic test methods (Thermal Humidity Bias--THB test methods with different parameter settings) have been compared: 40℃/95/100RH suggested by "a well known IEC standard" and 85 ℃/85/100RH required by the newer JEDEC standard.