High-Performance Contact-Doped WSe<sub>2</sub> Transistors Using TaSe<sub>2</sub> Electrodes
Bingjie Liu, Xiaofei Yue, Chenxu Sheng, Jiajun Chen, Chengjie Tang, Yabing Shan, Jinkun Han, Shuwen Shen, Wenxuan Wu, Lijia Li, Ye Lü, Laigui Hu, Ran Liu, Zhi‐Jun Qiu, Chunxiao Cong
Abstract
Two-dimensional (2D) transitional metal dichalcogenides (TMDs) have garnered significant attention due to their potential for next-generation electronics, which require device scaling. However, the performance of TMD-based field-effect transistors (FETs) is greatly limited by the contact resistance. This study develops an effective strategy to optimize the contact resistance of WSe 2 FETs by combining contact doping and 2D metallic electrode materials. The contact regions were doped using a laser, and the metallic TaSe 2 flakes were stacked on doped WSe 2 as electrodes. Doping the contact areas decreases the depletion width, while introducing the TaSe 2 contact results in a lower Schottky barrier. This method significantly improves the electrical performance of the WSe 2 FETs. The doped WSe 2 /TaSe 2 contact exhibits an ultralow Schottky barrier height of 65 meV and a contact resistance of 11 kΩ·μm, which is a 50-fold reduction compared to the conventional Cr/Au contact. Our method offers a way on fabricating high-performance 2D FETs.