Influence of GaAs buffer thickness on low-frequency and microwave noise in GaAs MESFETs grown on InP substrates

The dependence on the GaAs buffer layer thickness of the low and high frequency noise performance of GaAs MESFETs grown on InP substrates has been investigated. The 1/f noise magnitude at f=1 kHz and the minimum noise figure F_min in the 2-12 GHz frequency range, measured for a buffer layer thickness increases. The results obtained for a buffer thickness of 3 mu m or more are close to those observed on the bulk GaAs and are consistent with the GaAs layer crystalline improvement observed by X-ray diffraction measurements.