Gate-width scaling modulates electron velocity in AlGaN/GaN HEMTs

Key Points

• This research investigates how scaling the gate width affects electron transport and electrical characteristics in GaN HEMTs.
• Utilized a coupled drift-diffusion and Monte Carlo framework validated by experiments.
• Analyzed devices with a fixed gate length of 0.2 μm and varying gate widths from 200 μm to 80 μm.
• Measured parameters including peak electron velocity, normalized transconductance, drain current, and cutoff frequency.
• Peak electron velocity (ve) increased by 10% with reduced gate width.
• Higher normalized transconductance (gm) and drain current (Id) observed due to lower lattice temperature and reduced polarization Coulomb field scattering.
• Maximum cutoff frequency (fT,max) experienced a slight degradation due to increased extrinsic delay.