Admittance parameter and unilateral power-gain evaluation of GaN MESFET for microwave circuit applications

The admittance parameters and unilateral power gain of a nonself-aligned GaN MESFET incorporating the parasitic elements along with gate-length modulation are evaluated analytically in the present model. The cutoff frequency of the maximum available gain and the maximum frequency of oscillation are also determined in the model. For a GaN MESFET (4 μm×100 μm), the maximum frequency of oscillation is obtained to be about 2 GHz at zero gate bias. Using the present model, a unilateral power gain of 18 dB is predicted for the device. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 387–393, 2001.