Gate-Induced Source Tunneling FET (GISTFET)

Abstract

We propose a device, the gate-induced source tunneling FET (GISTFET), that uses two gate work functions to modulate lateral tunneling. The performance of the device is largely independent of the details of the chemical doping profile, potentially freeing device design from issues related to solid solubility, junction abruptness, and dopant variability. We demonstrate the advantages of the device over conventional TFETs using ballistic quantum transport simulations and discuss the possible role of scattering. The proposed device can be used to make all types of tunneling devices, but is particularly important for enabling steep swing, high current p-type transistors.

Electrostatic Doping in Semiconductor Devices

“…Other recently proposed ED TFET designs [34], [72] also offer distinct advantages. Ilatikhameneh et al [34] proposed to enhance the lateral field in a lateral ED tunnel junction using low-k dielectric spacers in between high-k gate dielectrics of the gated regions.…”

“…Pan and Chui ( [72] and references therein) discussed an ED-TFET design where the gate electrodes consisting of two different workfunction metals are physically and electrically shorted. This design addresses the limitation of minimizing the tunnel width of previous ED-TFET designs, which is limited by the lithography resolution of the intergate spacing.…”

“…This becomes more critical in the case of wide bandgap materials as the highly resistive intrinsic gap between the two ED regions may lead to a reduced ON-current and very high turn-ON voltages. Recently, Pan and Chui ( [72] and references therein) discussed to overcome this limitation in their new ED-TFET design. Such ideas can be explored for other ED devices as well.…”

Towards electrostatic doping approaches in ultra-thin body semiconductor materials and devices

“…[70,71,73,102,103] III-V materials GaN n-type SB-MOSFET (exp.) [51] GaAs Tunnel diode [96], GaN n-MOSFET [52], InAs TFET [118] GaAs EH Bilayer (exp.) [119], InAs EH bilayer LED [57,82] Polycrystalline materials CP based poly-Si TFT [120], IGZO TFT (exp.)…”

“…This becomes more critical in case of wide bandgap materials as the highly resistive intrinsic gap between the two ED regions may lead to a reduced on-current and very high turn-on voltages. Recently, Pan and Chui [118] proposed to overcome this limitation in their new ED-TFET design. Such ideas can be explored for other ED devices as well.…”