Low Resistance Contact to P-Type Monolayer WSe2

• DOI: 10.1021/acs.nanolett.3c04195
• Publication Date: 2024-05-07T12:18:20Z
• Authors: Jingxu Xie; Zuocheng Zhang; Haodong Zhang; Vikram Nagarajan; Wenyu Zhao; Ha-Leem Kim; Collin Sanborn; Ruishi Qi; Sudi Chen; Salman Kahn; Kenji Watanabe; Takashi Taniguchi; Alex Zettl; Michael F. Crommie; James Analytis; Feng Wang
• Keywords: ohmic contacts; charge transfer; 621; alpha-RuCl3; Condensed Matter Physics; 530; p-type monolayer WSe2 FET; MSD-VdW Heterostructures; Engineering; MSD-General; α-RuCl3; Physical Sciences; Nanotechnology; type-III band alignment; Nanoscience & Nanotechnology

Advanced microelectronics in the future may require semiconducting channel materials beyond silicon. Two-dimensional (2D) semiconductors, with their atomically thin thickness, hold great promise for future electronic devices. One challenge to achieving high-performance 2D semiconductor field effect transistors (FET) is the high contact resistance at the metal-semiconductor interface. In this study, we develop a charge-transfer doping strategy with WSe2/α-RuCl3 heterostructures to achieve low-resistance ohmic contact for p-type monolayer WSe2 transistors. We show that hole doping as high as 3 × 1013 cm-2 can be achieved in the WSe2/α-RuCl3 heterostructure due to its type-III band alignment, resulting in an ohmic contact with resistance of 4 kΩ μm. Based on that, we demonstrate p-type WSe2 transistors with an on-current of 35 μA·μm-1 and an ION/IOFF ratio exceeding 109 at room temperature.