Innovative through-Si 3D lithography for ultimate self-aligned planar Double-Gate and Gate-All-Around nanowire transistors

This paper reports the first electrical results of self-aligned multigate devices based on an innovative 3D-lithography process. HSQ resist exposition through the Silicon channel allows the formation of self-aligned trenches in a single step. Planar Double-Gate (DG) and Gate-All-Around Silicon Nanowire (GAA Si NW) transistors are fabricated with conformal SiO₂/Poly-Si:P gate stack and the first electrical results obtained with this technique are presented. The good nMOS performances (I_ON=1mA/μm at V_G=V_T+0.7V) with excellent electrostatics (SS down to 62mV/dec and DIBL below 10mV/V at L_G=80nm) are paving the way to the ultimate CMOS architecture. To meet all requirements of low-power SoCs, we also demonstrate the feasibility of fabricating such devices with High-K Metal-Gate (HK-MG) stack and their possible co-integration with FDSOI structures.