Low-frequency noise and interface states in GaAs homojunction far-infrareddetectors

Low-frequency noise characteristics of p-GaAs homojunction interfacial work -function internal photoemission (HIWIP) far-infrared (FTR) detectors are r eported. The noise was found to exhibit lif behavior related to interface s tates at frequencies below 1 kHz and frequency independent shot noise at hi gher frequencies. The noise expressions correctly predict the dark; current noise behavior, and provide a means of estimating both the gain and energy distribution of the interface states. The interface state density is estim ated to be in the order of 10(11) cm(-2) It has been shown that the estimat ed gain and noise equivalent power are in good agreement with the previous results obtained via optical measurements.