Modeling of lightly-doped drain and source contact with boron and nitrogen in graphene nanoribbon

• Main Authors: Wong, Kien Liong, Tan, Beng Rui, Chuan, Mu Wen, Hamzah, Afiq, Rusli, Shahrizal, Alias, Nurul Ezaila, Mohamed Sultan, Suhana, Lim, Cheng Siong, Tan, Michael Loong Peng
• Format: Article
• Published: Physical Society of the Republic of China 2019
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utm.my/id/eprint/88407/; http://dx.doi.org/10.1016/j.cjph.2019.09.026
• Institution: Universiti Teknologi Malaysia

Graphene, a monolayer carbon atoms arranged in hexagonal honeycomb lattice possesses impressive electronic properties. It is utilized as channel, source and drain contact in graphene nanoribbon field-effect transistor (GNRFET). Zigzag graphene nanoribbon (ZGNR) is used as semi-metallic drain and source terminal to a pristine armchair graphene nanoribbon (AGNR) that acts as a semiconducting channel. In addition, a single dopant, either nitrogen or boron is added to create lightly-doped drain and source contact. The electronic properties of graphene nanoribbon (GNR) with lightly-doped drain and source contacts are obtained from tight-binding approach. With self-energy matrices, the lightly-doped contacts Hamiltonian matrices are combined with the pristine channel Hamiltonian matrix. The density of states (DOS) are simulated based on the non-equilibrium Green's Function (NEGF) formalism. Our findings are then compared with published research work. Furthermore, it is demonstrated that the DOS of the overall GNR structure still retain a small band gap and possess semiconducting properties when the channel is connected to semi-metallic contact at the drain and source terminal.