Reconfigurable Two-Dimensional Air-Gap Barristors

Abstract

Reconfigurable logic circuits implemented by two-dimensional (2D) ambipolar semiconductors provide a prospective solution for the post-Moore era. It is still a challenge for ambipolar nanomaterials to realize reconfigurable polarity control and rectification with a simplified device structure. Here, an air-gap barristor based on an asymmetric stacking sequence of the electrode contacts was developed to resolve these issues. For the 2D ambipolar channel of WSe 2 , the barristor can not only be reconfigured as an n-or p-type unipolar transistor but also work as a switchable diode. The air gap around the bottom electrode dominates the reconfigurable behaviors by widening the Schottky barrier here, thus blocking the injection of both electrons and holes. The electrical performances can be improved by optimizing the electrode materials, which achieve an on/off ratio of 10 4 for the transistor and a rectifying ratio of 10 5 for the diode. A complementary inverter and a switchable AND/OR logic gate were constructed by using the air-gap barristors as building blocks. This work provides an efficient approach with great potential for low-dimensional reconfigurable electronics.

Modulation of Contact Resistance of Dual‐Gated MoS2 FETs Using Fermi‐Level Pinning‐Free Antimony Semi‐Metal Contacts

“…In this sense, Zhang et al have reported that 2D semiconductors can be electrostatically doped by applying gate-voltages despite the existence of air gap at the metal-2D semiconductor junction. [33] Therefore, although the existence of the air gap at metal-MoS 2 junction may affect the top-gate performance, the electrostatic modulation of R C and R jun by V TG is still possible. S5 (Supporting Information).…”

“…To investigate the impact of V TG on R C , we fabricated DG MoS 2 FETs with Sb (and DG MoS 2 FETs with Ti as a reference) electrodes on a global bottom‐gate (BG) silicon substrate capped with 285 nm SiO 2 (To ensure the screening effect of metal electrode against V TG , total thickness of ≈25 nm is used). [ 33 ] The TG of the device is formed by an exfoliated hBN flake (≈50 nm) with a TG electrode of Ti/Au (5/70 nm). The detailed fabrication process is described in the Experimental Section.…”

Nanomaterials for light-mediated therapeutics in deep tissue

“…The identical nanosystem was also applied for a photothermal/NO-based combined therapy. 259 The NIR afterglow produced under ultrasound irradiation activated PDA layers to liberate NO and induces a photothermal effect. The liberation of NO and the temperature gradient on the NPs caused them to self-propel, enhancing endocytosis into tumour cells by 2 fold.…”

Electric Tuning of Vortex Ratchet Effect in NbSe2

“…33 The Schottky barrier can also form when there exists an air gap around the interface between the flake and bottom electrodes. 34 The Schottky barrier may vary from contact to contact, giving rise to a moderate rectification effect of the AC current from source to drain. As a result, the net current passing through the sample consists of both DC and AC components, as illustrated in Figure 4(g).…”

“…An effective DC bias might be induced by passing the AC current through nonideal contacts with Schottky barriers. − Such barriers occur at source and drain electrodes contacting NbSe 2 , as a result of charge transfer between them due to a difference in work functions of Au (4.7 eV) and NbSe 2 (5.9 eV) . The Schottky barrier can also form when there exists an air gap around the interface between the flake and bottom electrodes . The Schottky barrier may vary from contact to contact, giving rise to a moderate rectification effect of the AC current from source to drain.…”