Subcircuit Compact Model for Dopant-Segregated Schottky Gate-All-Around Si-Nanowire MOSFETs

In this paper, we demonstrate analytical device models and a unique subcircuit approach to physically and accurately model the dopant-segregated Schottky (DSS) gate-all-around (GAA) Si-nanowire (SiNW) MOSFETs. The direct current characteristics of the DSS GAA SiNW MOSFETs are investigated through numerical simulations and fabricated devices. Transport mechanisms are studied and explained with numerical devices from ambipolar thermionic tunneling to unipolar drift-diffusion and a combination of both as the dopant segregation doping and thickness are varied. The convex curvature in the I_ds- V_ds characteristics is accurately reproduced by the subcircuit compact model, and it is shown for the first time that such a unique g_ds-V_ds characteristic in DSS devices is only feasible to be modeled by the subcircuit approach.