DESIGN AND SIMULATION OF DRIFT-DIFFUSION AND HYDRODYNAMIC MODELS FOR AlGaN/GaN HEMTs

Gallium Nitride based HEMTs because of their peculiar material properties are widely used to realize high power, high frequency communication device and very much suitable for bio-sensing application. But to realize AlGaN/GaN HEMTs for these application many issues are remain to investigate for further improvement in the device technology like design optimization and other performance limiting factor. In this work we proposed two electron transportation models these are drift-diffusion and hydrodynamic models both having their own feasibility to be used in particular application. Now a day’s hydrodynamic model is becoming more popular as this model is suitable for deep submicron technology where conventional drift-diffusion model fails to deliver accurate results in case of deep submicron technology the reason is that drift diffusion model neglects some phenomenal effects like velocity overshoot and diffusion associated with the carrier. As drift-diffusion model require little parameterization so this model require less time to simulate the device on the other hand Hydrodynamic model require more parameterization so the time require for its simulation is more. These transportation models are design and simulated using commercially available software silvaco-ATLAS and the results obtained after the simulation of drift-diffusion and hydrodynamic models are compared and analyzed to better understand the device characteristic for further improvement in device technology.