About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
Journal of Applied Physics
Paper
Low-frequency noise in self-aligned bipolar transistors
Abstract
We report the first study of the low-frequency noise in self-aligned npn bipolar transistors, which use the polysilicon emitter. Some of these devices showed excess noise spectra different from the 1/f law generally observed in diffused junction transistors, and the spectral shape S(f) was found to vary from sample to sample. For instance, we have observed two different characteristics, S(f)∼1/f and S(f)∼1/[1+(f/f0)2], in two adjacent transistors on the same chip. We attribute the latter to carrier trapping in the oxide barrier at the poly-/monosilicon boundary, whose inhomogeneity could explain the wide variation of the noise spectra.