Local volume inversion and corner effects in triangular gate-all-around MOSFETs

We report on the fabrication and measurement of triangular gate-all-around (GAA) and tri-gate devices. On the small triangular cross-section devices we observe a significant enhancement of the extracted carrier mobility (up to ~1000cm²/Vs). We assign this effect to enhanced conduction in the sharp corners of our device, and local volume inversion. The new concept of local volume inversion is supported by a boosting of experimental g_m in the subthreshold region. Furthermore, we have carried out 3D numerical simulations, which support these findings