Reliability of Low-Voltage Tantalum Polymer Capacitors

This paper briefly reviews earlier work which first assessed the reliability of 6V tantalum polymer capacitors. A physics-based acceleration formula that better models the interaction of voltage and temperature stress is presented and discussed. New observations are made about the original test data in light of the physics-based acceleration model as well as new testing done on 6V capacitors since the original paper was presented. Then the focus is shifted to accelerated lifetesting of 4V and 2.5V tantalum polymer capacitors. Accelerated lifetest data for 4V and 2.5V capacitors are presented and are compared and contrasted with the 6V data. Similarities and differences in the behavior of the lower-voltage devices with respect to each other and the 6V devices are discussed. The physical bases of these similarities and differences are explored, and conclusions are reached regarding the expected long-term reliability of low-voltage tantalum polymer capacitors.