Trapping of hot electron behavior by trap centres located in buffer layer of a wurtzite phase GaN MESFET has been simulated using an ensemble Monte Carlo simulation.The simulated results show the trap centres are responsible for current collapse in GaN MESFET at low temperatures.These electrical traps degrade the performance of the device at low temperature.On the opposite,a light-induced increase in the trap-limited drain current results from the photoionization of trapped carriers and their return to the channel under the influence of the built in electric field associated with the trapped charge distribution.The simulated device geometries and doping are matched to the nominal parameters described for the experimental structures as closely as possible,and the predicted drain current and other electrical characteristics for the simulated device including trapping centre effects show close agreement with the available experimantal data.
展开▼
