High-frequency time-domain modeling of GaAs FETs using hydrodynamic model coupled with Maxwell´s equations

A high frequency full wave model for microwave and millimeter wave GaAs Field Transistors (FET) is presented. The consists of two coupled models for the solid-state and electromagnetic parts of the problem. In the solid-state part, a hydrodynamic model consisting of the conservation equations for carrier density, energy, and momentum is utilized. All the conservation equations are solved with minimum simplifications. On the electromagnetic side, a 3D model consisting of Maxwell´s equations is used. The time domain simulation of the device is performed using finite difference method. Numerical results of the presented model for a 0.5 /spl mu/m MESFET show that wave effect plays a crucial role in modulating fields and electron velocities inside the active device. The wave propagation is detected and found to cause considerable variations in field distribution and electron velocities.<>