Virtual-Source Modeling of N-polar GaN MISHEMTS

Nitrogen-polar (N-polar) Gallium Nitride (GaN) deep-recess high-electron mobility transistors (HEMTs) have demonstrated exceptional power density (8 W/mm) and high efficiency at 30 and 94 GHz. Unlike the conventional Galliumpolar GaN which have typical Silicon Nitride passivation, the Npolar deep-recess structure has a GaN cap layer added in the access region of the transistor to enhance the conductivity while reducing the DC-to-RF dispersion. Previously, the MIT virtual source (VS) model has been proposed as a physics-based approach to modeling Ga-polar devices. This work investigates the application of the VS model to N-polar GaN HEMTs. We present a comparison of DC-IV between the developed model and a fabricated device to demonstrate good agreement.