Flicker Noise in GaN/Al Ga N Doped Channel Heterostructure Field Effect Transistors

We have investigated noise characteristics of novel GaN/Al0:15Ga0:85N doped channel heterostructure field effect transistors designed for high-power density applications. The measurements were carried out for various gate bias VGS and the drain voltage VDS varying from the linear to the saturation regions of operation VDS > 5 V. Our results show that flicker, e.g., 1=f noise, is the dominant limiting noise of these devices; and the Hooge parameter is on the order of 10 5 10 . The gate voltage dependence of 1=f noise was observed in the linear region for all examined VGS and in the saturation region for VGS > 0. These results indicating low values of the Hooge parameter are important for microwave applications.