Low-voltage failures in multilayer ceramic capacitors: a new accelerated stress screen

A method of screening out all potential low-voltage failures in manufactured lots of multilayer ceramic capacitors (MLCC) is presented. The method eliminates all the potential failures in capacitor lots. This test uses the technique of highly accelerated life-testing (HALT) previously developed by the authors (ibid., vol.37, p.129-34, 1987). In this technique, 50-V rated capacitors are subjected to accelerated testing at 140 degrees C and 400 V DC, instead of the standard 125 degrees C and 100 V DC environment. The approach is based on the concept that low-voltage failures are caused by extrinsic defects in MLCCs and that these defects can be eliminated in a very short using high voltage and temperature acceleration. It is shown that the HALT test can eliminate the 85/85 test, since a single short HALT test can completely characterize the quality and reliability of ceramic capacitors, both for rated voltage and low-voltage applications.<>