Generation–recombination noise in bipolar transistors

Abstract

The generation–recombination (g–r) noise in bipolar junction transistors (BJTs) is due to the deep-level impurities in the p–n junctions. The larger the amplitude of g–r noise, the worse the quality of BJTs, so that measuring the amplitude of the g–r noise is way of estimating the reliability of BJTs. In some papers, it is assumed that the amplitude of g–r noise is proportional to the square of base current ( I b 2), but in a few papers it has been reported that this relation is more complex. In this paper the amplitude of g–r noise versus base current is discussed, the theoretical and experiment results demonstrate that the g–r noise and burst noise signal may be observed only in a certain range of base current, and the law S( f)∝ I b 2 is not valid. It means that we must measure g–r noise and observe burst noise signal over a wide range of base current to estimate the concentration of deep-level impurities in p–n junction and hence the reliability of BJTs.