Environmental stress testing

Environmental stress testing (EST) is a means of systematically improving the reliability of electronic systems. In this paper, we discuss: — The background and rationale for EST; — The utility of accelerated testing to achieve robust design margins, high component quality, and well-controlled manufacturing processes; — Various issues that must be addressed to make EST a safe and effective process, including the principal modes of implementation, the application of various kinds of stress stimuli and the associated faults that are precipitated, and the classification of failure types; — Implementation issues, including methodology issues related to the stimulation and detection of failures, and the use of baseline experiments to determine the operational and destruct limits of a product, so as to arrive at a safe and effective EST regimen; and — Economic issues, including the importance of failure mode analysis and corrective action to achieve a cost-effective EST methodology.