Ambient temperature effects on DC behaviour of GaAs MESFET devices

DC measurements at different temperatures on a wide range of different-sized MESFET devices show that temperature effects change the behaviour of the device. The results indicate that, as the drain current is reduced, the behaviour of the device becomes more susceptible to temperature effects. In the main, this is due to the temperature dependency of the pinchoff point. The data presented show that the dependency of the pinchoff point on temperature does not follow a straight-line law, but has three regions of operation, each with a different temperature coefficient. The data also show that, as the temperature is reduced, the dependency of the pinchoff point on the drain-source voltage increases.