Аccelerated Tests of the Storageability of Tantalum Capacitors Using the Thermal Method

Abstract

By means of the accelerated valuation method of storageability of capacitors on the basis of influence of the increased environment temperature without application of electrical loading researches at a production stage are conducted. When carrying out accelerated tests at a temperature of 398 K (125ºC) at the capacitor without application of voltage to it there is an aging of an oxide layer on the tantalum anode of the capacitor. The method of calculation of duration of accelerated tests which comprised 28.18 hours is given. 5 different nominals by 45 pieces in each of 3 selections tantalum oxide-coated and semiconductor the chip capacitors and 2 selections of tantalum volume and porous capacitors for detection of low-quality production are tested. In the course of the tests corresponding to annual cycles up to 30 years measurement of parameters criteria of the conformance were taken: capacitance, tangent of angle of losses, leakage current, the equivalent series resistance of capacitors. From the given dependences it is set that in the course of storage some parameters undergo changes to the termination of storage life imitating the period of more than 25 years. Deviations from the monotonic dependence for all selections are related to the critical moments of the influence of heat. It is marked that the greatest changes are undergone by the leakage current parameter; other parameters are in normal limits.