Low-frequency noise in GaAs MESFETs related to backgating effects

The influence of the backgating effect on low-frequency noise in GaAs MESFETs grown by molecular beam epitaxy is investigated. The low-frequency noise is of the 1/f type superimposed on generation-recombination noise. We show that the backgating effect, although it reduces the current, increases current fluctuations and, hence, noise. Furthermore, it is shown that the incorporation of a low-temperature grown GaAs buffer, by MBE, significantly reduces the sensitivity of the noise level of the device to backgate bias.