Scaling of Trigate nanowire (NW) MOSFETs to sub-7 nm width: 300 K transition to Single Electron Transistor

In this paper we show that on scaling nanowire width from 20 nm down to sub-7 nm regime, together with achieving excellent short channel effect control (DIBL = 12 mV/V for LG = 20 nm), we hit a dramatic transition in transport mechanism from monotonously increasing ID–VG of a FET to oscillating ID–VG of a Single Electron Transistor. This transition in transport mechanism is brought about by process induced channel potential variability. It poses a challenge to further scaling of nanowire MOSFETs. However, we show that it provides an exciting opportunity to cointegrate Single Electron Transistors with high-k/metal gate operating at room temperature (at VD = ±0.9 V) with the state-of-the-art nanowire MOSFETs enabling large scale manufacturing of Beyond Moore devices.

► We fabricated Trigate nanowire (NW) - MOSFETs with width down to 5 nm. ► We demonstrated excellent electrostatic control in sub-7 nm width NWMOSFETs featuring 20 nm gate length (DIBL = 12 mV/V, SS = 62 mV/dec). ► Transition in transport mechanism from FET to that of Single Electron Transistor (SET) at 300 K is observed. ► Surface roughness in nanowires leading to disordered potential is shown to be the cause of the transition. ► 300 K operating SETs with very high VD ( = 0.9 V) featuring high-k/metal gate are demonstrated for the first time.