Superior Performance of 5-nm Gate Length GaN Nanowire nFET for Digital Logic Applications

We investigate the performance of 5-nm gate length GaN nMOS nanowire field effect transistor (GaN-NWnFET) of various geometrical shapes, around the limits of cross-sectional scalability, using atomistic quantum transport simulations. For square cross-sections, the benchmarking results with the simulated Si-NW-nFET reveal over 30% enhancement in GaN drive current in both low standby power (LP - I
_OFF
= 1 nA/μm) and high performance (HP - I
_OFF
= 100 nA/μm) applications. Further performance enhancement is observed with the use of non-square geometries that are akin to GaN's wurtzite crystal structure. Particularly, for T
_nw
= 2.4 mn, triangular cross-section GaN-NW-nFETs exhibit the smallest subthreshold swing, down to 62 mv/decade, excellent drive current, I
_DSAT
> 2 × 10
⁶
μA/μm
²
and superior energy-delay product compared to simulated Si-NW-nFET.