The External Electric Field-Induced Tunability of the Schottky Barrier Height in Graphene/AlN Interface: A Study by First-Principles

Abstract

Graphene-based van der Waals (vdW) heterojunction plays an important role in next-generation optoelectronics, nanoelectronics, and spintronics devices. The tunability of the Schottky barrier height (SBH) is beneficial for improving device performance, especially for the contact resistance. Herein, we investigated the electronic structure and interfacial characteristics of the graphene/AlN interface based on density functional theory. The results show that the intrinsic electronic properties of graphene changed slightly after contact. In contrast, the valence band maximum of AlN changed significantly due to the hybridization of Cp and Np orbital electrons. The Bader charge analysis showed that the electrons would transfer from AlN to graphene, implying that graphene would induce acceptor states. Additionally, the Schottky contact nature can be effectively tuned by the external electric field, and it will be tuned from the p-type into n-type once the electric field is larger than about 0.5 V/Å. Furthermore, the optical absorption of graphene/AlN is enhanced after contact. Our findings imply that the SBH is controllable, which is highly desirable in nano-electronic devices.

Highly Sensitive Band Alignment of the Graphene/MoSi2N4 Heterojunction via an External Electric Field

“…Note that the larger electric field has been realized in experiments by the pulsed alternating current field technology (0.60 V·Å –1 ) − and in situ surface doping technique (0.72 V·Å –1 ); − we suggest that similar methods can also be performed to generate 0.4 V·Å –1 electric field here. Noteworthily, with a 0.1 V·Å –1 increase of the external electric field, the SBH of the heterojunction apparently varies about 0.2–0.3 eV, greatly larger than that of GR/MoS 2 and GR/AlN heterostructures. , Generally, the external electric field could effectively engineer the barrier heights and types of the GR/MoSi 2 N 4 heterojunction, decreasing the contact resistance and improving the performance of electronic devices. , …”

Influence of N‐vacancy on the electronic and optical properties of bulk GaN from first‐principles investigations

“…There is no doubt that the first‐principle is an effective tool to study the natural properties of a solid at the atomic or electronic level 42‐46 . To study the vacancy effect, all calculations of GaN with the N‐vacancy were calculated by the first‐principles calculation, as implemented in the CASTEP code 47,48 .…”

Gate-voltage-induced reversible electrical phase transitions in Mo0.67W0.33Se2 devices

“…[1][2][3][4] For example, it has been theoretically predicted that the bandgaps of various 2D materials can be tuned by applying a vertical electric field. [5][6][7][8][9] For TMDC materials, both the structural phase and transition metal element group mainly determine the electrical phase such as the semiconductor, superconductivity and charge density wave. 10,11 Various phase transitions in structures or quantum states for 2D TMDCs of general formula MX 2 , where M is a group-6 transition metal (Mo or W) and X is a chalcogenide (S, Se, or Te), have been explored for both electrical engineering and quantum electronics applications.…”