An Analytical Drain Current Model for AlGaN/GaN Metal Insulator Semiconductor Heterostructure Field Effect Transistor (MISHFET): A Comparative Study with Conventional HFETs for High Power Microwave Applications

An analytical drain current model of a novel device architecture- AlGaN/GaN Metal Insulator Semiconductor Heterostructure Field Effect Transistor (MISHFET) has been presented to assess the microwave performance of the device for sub micron gate lengths. The model has a broad utility as it is equally applicable to HFETs as well. Both the structures have been extensively studied and a comparison is made between them. The proposed model is capable of modeling electrical characteristics like sheet carrier density, threshold voltage, drain current, cut-off frequency, etc. The MISHFET shows a considerable 36% increase in drain saturation current. The results obtained are compared with experimental data & show excellent agreement.