Reliability Prediction of Silicon Bipolar Transistors by Means of Noise Measurements

The results of theoretical and experimental investigations on flicker-and burst noise are used in order to point out the relation between excess noise and the internal properties of the transistors. Noise is show to be a good means of characterization of the surface parameters. A HTRB step stress test and a complementary long time storage are described. It emerges from the results that previous excess noisemeasurements give a good prediction of the failures and that noisiness is a very sensitive degradation parameter, the increase of which can be, sometimes, the only indicator of an imminent failure. A screening method is deduced.