MODAL-ANALYSIS OF NOISE IN SIGNAL-PROCESSING-IN-THE-ELEMENT DETECTORS

Detector noise limits the performance of signal-processing-in-the-elem ent detectors. For detectors to be optimized, an expression for the si gnal and noise must be found. The results of the eigenmode solution to the charge transport problem are used to derive the power spectral de nsity of the noise in analytic form. This result is then coordinated w ith a similarly obtained modulation transfer function to yield a frequ ency-dependent signal-to-noise ratio (SNR). The SNR is used to reveal performance trends over several ranges of detector parameters. The mos t important result is that the contact boundary velocity strongly cont rols the SNR. The optimum SNR condition occurs when the contacts are n ot perfectly ohmic but exhibit a partially blocking behavior. (C) 1996 Optical Society of America