High‐Performance Solution‐Processed 2D P‐Type WSe2 Transistors and Circuits through Molecular Doping

• Published in: Advanced materials (Weinheim) Vol. 35; no. 7; pp. e2208934 - n/a
• Main Authors: Zou, Taoyu, Kim, Hyun‐Jun, Kim, Soonhyo, Liu, Ao, Choi, Min‐Yeong, Jung, Haksoon, Zhu, Huihui, You, Insang, Reo, Youjin, Lee, Woo‐Ju, Kim, Yong‐Sung, Kim, Cheol‐Joo, Noh, Yong‐Young
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01-02-2023
• Subjects: chalcogenide layered p‐type semiconductors; Circuits; Doping; Free surfaces; High gain; Hole mobility; Inks; Integrated circuits; Layered materials; Materials science; molecular doping; Semiconductor devices; solution process; Substrates; thin film transistors; Transistors; Van der Waals film; WSe 2 nanosheets
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202208934

Semiconducting ink based on 2D single‐crystal flakes with dangling‐bond‐free surfaces enables the implementation of high‐performance devices on form‐free substrates by cost‐effective and scalable printing processes. However, the lack of solution‐processed p‐type 2D semiconducting inks with high mobility is an obstacle to the development of complementary integrated circuits. Here, a versatile strategy of doping with Br2 is reported to enhance the hole mobility by orders of magnitude for p‐type transistors with 2D layered materials. Br2‐doped WSe2 transistors show a field‐effect hole mobility of more than 27 cm2 V−1 s−1, and a high on/off current ratio of ≈107, and exhibits excellent operational stability during the on‐off switching, cycling, and bias stressing testing. Moreover, complementary inverters composed of patterned p‐type WSe2 and n‐type MoS2 layered films are demonstrated with an ultra‐high gain of 1280 under a driving voltage (VDD) of 7 V. This work unveils the high potential of solution‐processed 2D semiconductors with low‐temperature processability for flexible devices and monolithic circuitry.
Solution‐processed high‐performance p‐type WSe2 thin‐film transistor is successfully fabricated by Br2‐doping with a field‐effect hole mobility of more than 27 cm2 V−1 s−1, and a high on/off current ratio of ≈107. The resulting complementary inverters with patterned p‐type WSe2 and n‐type MoS2 layered films reaches an ultra‐high gain of 1280 under a driving voltage (VDD) of 7 V.