High temperature DC and RF performance of p-type diamond MESFET: comparison with n-type GaAs MESFET

The DC and RF performance of a p-type diamond MESFET is simulated and compared with the simulated performance of an n-type GaAs MESFET over the operating temperature range, 300-923 K. Power performance of a diamond MESFET is shown to improve with increasing temperature and to exceed that of a GaAs MESFET when operated at temperatures higher than 550 and At 923 K the simulated diamond MESFET produces about 0.8 W/mm of output power for an operating frequency of 5 GHz. Small signal current gain for a diamond MESFET is also found to increase with temperature. The cut-off frequency, f/sub T/, of a diamond MESFET at 923 K is comparable with that of a GaAs MESFET at room temperature. It is concluded that there are microwave power applications of MESFET's in p-type diamond but otherwise conventional design is limited to high temperature.>