In this paper, electrostatically configurable 2D tungsten diselenide (WSe2) electronic devices are demonstrated. Utilizing a novel triple‐gate design, a WSe2device is able to operate as a tunneling field‐effect transistor (TFET), a metal–oxide–semiconductor field‐effect transistor (MOSFET) as well as a diode, by electrostatically tuning the channel doping to the desired profile. The implementation of scaled gate dielectric and gate electrode spacing enables higher band‐to‐band tunneling transmission with the best observed subthreshold swing (SS) among all reported homojunction TFETs on 2D materials. Self‐consistent full‐band atomistic quantum transport simulations quantitatively agree with electrical measurements of both the MOSFET and TFET and suggest that scaling gate oxide below 3 nm is necessary to achieve sub‐60 mV dec−1SS, while further improvement can be obtained by optimizing the spacers. Diode operation is also demonstrated with the best ideality factor of 1.5, owing to the enhanced electrostatic control compared to previous reports. This research sheds light on the potential of utilizing electrostatic doping scheme for low‐power electronics and opens a path toward novel designs of field programmable mixed analog/digital circuitry for reconfigurable computing.
The minimization of the subthreshold swing (SS) in transistors is essential for low‐voltage operation and lower power consumption, both critical for mobile devices and internet of things (IoT) devices. The conventional metal‐oxide‐semiconductor field‐effect transistor requires sophisticated dielectric engineering to achieve nearly ideal SS (60 mV dec−1at room temperature). However, another type of transistor, the junction field‐effect transistor (JFET) is free of dielectric layer and can reach the theoretical SS limit without complicated dielectric engineering. The construction of a 2D SnSe/MoS2van der Waals (vdW) heterostructure‐based JFET with nearly ideal SS is reported. It is shown that the SnSe/MoS2vdW heterostructure exhibits excellent p–n diode rectifying characteristics with low saturate current. Using the SnSe as the gate and MoS2as the channel, the SnSe/MoS2vdW heterostructure exhibit well‐behavioured n‐channel JFET characteristics with a small pinch‐off voltage
- NSF-PAR ID:
- 10459795
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 31
- Issue:
- 49
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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