Direct evaporation of single-crystal metal contacts for 2D semiconductors

• 成果类型: Article
• 署名作者: Zhang, Ying; Liu, Chang; Wang, Huiting; Teng, Guichen; Qin, Yilu; Niu, Wencheng; Ding, Shuimei; Wu, Binmin; Wu, Shuaiqin; Chen, Yan; Yang, Ni; Lin, Tie; Shen, Hong; Meng, Xiangjian; Liu, Yuan; Zou, Xuming; Wang, Xudong; Liao, Lei; Chu, Junhao; Li, Lain-Jong; Wang, Jianlu
• 署名单位: Chinese Academy of Sciences; Shanghai Institute of Technical Physics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Hunan University; Fudan University; National University of Singapore; Fudan University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-8075; 1095-9203
• DOI: 10.1126/science.aee3132
• 发表日期: 2026-08-27
• 页码: 938-943
• 关键词: 2-dimensional materials; monolayer; transistors; resistance; graphene

摘要

Metal contacts remain one of the key bottlenecks in two-dimensional (2D) semiconductor electronics. We developed an atomic-scale step-by-step evaporation method to directly grow single-crystal metals on monolayer semiconductors with clean interfaces. This method accesses a distinct growth-kinetic window that suppresses secondary nucleation and promotes lateral coalescence, enabling van der Waals epitaxy of diverse metals-including bismuth, silver, indium, gold, and palladium-on molybdenum disulfide (MoS2) and tungsten diselenide (WSe2). The single-crystal metals support ultrathin conduction, provide spatially uniform work functions, and exhibit improved thermal robustness. As contacts, they show minimal Fermi-level pinning, approaching the Schottky-Mott limit. With bismuth and palladium contacts, monolayer MoS2 and WSe2 transistors achieved ultralow n- and p-type contact resistances of 36 and 145 ohm-micrometers, respectively, and short-channel currents both above 1.1 milliampere per micrometer.