First Demonstration of Junctionless Accumulation-Mode Bulk FinFETs With Robust Junction Isolation

A junctionless-accumulation-mode (JAM) p-channel MOSFET is successfully implemented based on a junction-isolated bulk FinFET for the first time. The JAM devices with a fin width of 16 nm show outstanding transfer characteristics: 1) subthreshold swing (SS_min) = 68 mV/dec; 2) drain-induced-barrier-lowering is 9 mV/V; and 3) I_ON/I_OFF ratio >1 × 10⁶. The JAM devices with smaller fin widths or longer gate lengths give superior short-channel characteristics and higher threshold voltages (V_th) due to their enhanced gate electrostatic controllability. The reverse back bias modulates V_th and SS favorably by virtue of a body-tied device, maintaining the substrate current due to junction leakage of <;1 × 10^-11 A.