The Determination and Analysis of Aging Mechanisms in Accelerated Testing of Selected Semiconductors, Capacitors and Resistors

THREE principal categories of problems confront the parts reliability engineer. Initially, it is desired to assign failure rate or reliability numbers to a parts performance under a specific set of application conditions. If there is limited or no data upon which to make a prediction having the desired confidence level, testing may be required. This leads to the problem of establishing a set of test conditions that will supply useful and valid information within a limited time and money budget. The time restrictions enforce some form of accelerated testing. Then the validity of the accelerated test conditions and the mathematical relationship of these results to those results that would have been obtained under some standard set of conditions must be justified. This paper will discuss the progress made in applying physics of failure data, experiments and concepts to establishing accelerated test conditions and to evaluating the acceleration factor to be applied in relating the results to some standard test condition. The parts to be discussed are examples of high volume production, high volume usage and consist of a lead-alumino-silicate glass capacitor, silicon passivated planar transistors, silicon alloy-junction diodes and film resistors. Specific subjects to be discussed are: 1. The development of physical models to predict the parts reaction to stress. 2. Use of the model to predict failure mechanisms and failure modes to be encountered under various stresses. 3. Selection of stresses for accelerated testing. 4. Results of accelerated testing; failure mechanisms and modes encountered and analytical techniques.