Realizing a future of 2D semiconductor-based devices requires new approaches to channel passivation and nondestructive contact engineering. Here, a facile one-step technique is shown that simultaneously utilizes monolayer fluorinated graphene (FG) as the passivation layer and contact buffer layer to 2D semiconductor transistors. Monolayer graphene is transferred onto the MoS2, followed by fluorination by XeF2 gas exposure. Metal electrodes for source and drain are fabricated on top of FG-covered MoS2 regions. The MoS2 transistor is perfectly passivated by insulating FG layer and, in the contacts, FG layer also acts as an efficient charge injection layer, leading to the formation of Ohmic contacts and high carrier mobility of up to 64 cm2 V−1 s−1 at room temperature. This work shows a novel strategy for simultaneous fabrication of passivation layer and low-resistance contacts by using ultrathin functionalized graphene, which has applications for high performance 2D semiconductor integrated electronics.
H.R. and D.\u2010H.K. contributed equally to this work. This work was supported by the National Research Foundation of Korea (NRF\u20102021R1A2C3014316 and NRF\u20102018M3D1A1058793), the Creative\u2010Pioneering Researchers Program through Seoul National University (SNU), the National Research Council of Science & Technology (NST) grant by the Korea government (MSIT) (No. CRC\u201020\u201001\u2010NFRI), the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (NRF\u20102021M3H4A1A01079358), and the National Science Foundation MRSEC program under NSF Award Number DMR\u20101720633. This work was carried out in the Material Research Laboratory Central Facilities, the Micro and Nano Technology Laboratory, and the iMRSEC shared facilities DMR\u20101720633.
