Testing of quasi-ballistic field-effect transistors with Schottky gate by 1/f noise measurements

We perform measurements of the 1/f voltage fluctuations in the channels of quasi-ballistic field-effect transistors with a V-shaped Schottky gate for the first time. Along with dependences typical of this class of devices, we reveal two new characteristics, namely, a specific current dependence of the noise spectrum due to the leakage current through the buffer layer and an unusual dependence of the spectrum shape on the gate voltage, which turns out to be related to the low-quality (or insufficient) training of samples. The obtained results show a high sensitivity of the noise-analysis method to the occurrence of leakage currents and can be used for nondestructive device-quality testing aimed at revealing unstable samples. © 2005 Springer Science + Business Media, Inc.