1/f noise and RTS in advanced bipolar technologies

The low-frequency noise observed on advanced junction bipolar transistors consist of 1/f noise as well as Random telegraph Signals (RTS). In relatively small emitter-base junction areas, RTS is seen in the spectra which can be differentiated from the typical generation-recombination (gr) noise through time domain analysis. For most cases, the 1/f noise can be modeled primarily with a current noise source in the base SIB. There are cases, however, the noise originates primarily in the collector side due to SIC, which has been neglected in modeling equations. We have designed two different measurement and analysis systems where the effect of SIC and SIB can be differentiated and separately modeled through correlated noise measurements that are performed at the collector and base or collector and emitter. Cross-power spectral density, as well as coherence is used to extract different noise components. Variable temperature low-frequency noise measurements to extract the different components of SIB revealed that the diffusion noise due to mobility fluctuation, fluctuations in the recombination at the surface of the emitter/base depletion region, and fluctuations in the interfacial oxide tunneling barrier height, (and thus the tunneling probability of the carrier) are the components that need to be modeled. The results of the experimental data as well as modeling equations and techniques will be discussed.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.