TY - JOUR
T1 - Distinctive Field-Effect Transistors and Ternary Inverters Using Cross-Type WSe2/MoS2Heterojunctions Treated with Polymer Acid
AU - Kim, Jun Young
AU - Park, Hyeon Jung
AU - Lee, Sang Hun
AU - Seo, Changwon
AU - Kim, Jeongyong
AU - Joo, Jinsoo
N1 - Funding Information:
This research was supported by a National Research Foundation of Korea (NRF) grant, funded by the Korean Government (No. 2018R1A2B2006369). Prof. J.K. also acknowledges the financial support by the NRF, funded by the Korean Government (No. 2019R1A2C1006586). We thank Professor Jaekwang Lee at Pusan National University for fruitful discussions regarding the logic circuit.
Publisher Copyright:
© 2020 American Chemical Society.
PY - 2020/8/12
Y1 - 2020/8/12
N2 - The electrical and optical characteristics of two-dimensional (2D) transition-metal dichalcogenides (TMDCs) can be improved by surface modification. In this study, distinctive field-effect transistors (FETs) were realized by forming cross-type 2D WSe2/MoS2 p-n heterojunctions through surface treatment using poly(methyl methacrylate-co-methacrylic acid) (PMMA-co-PMAA). The FETs were applied to new ternary inverters as multivalued logic circuits (MVLCs). Laser confocal microscope photoluminescence spectroscopy indicated the generation of trions in the WSe2 and MoS2 layers, and the intensity decreased after PMMA-co-PMAA treatment. For the cross-type WSe2/MoS2 p-n heterojunction FETs subjected to PMMA-co-PMAA treatment, the channel current and the region of anti-ambipolar transistor characteristics increased considerably, and ternary inverter characteristics with three stable logic states, "1", "1/2", and "0", were realized. Interestingly, the intermediate logic state 1/2, which results from the negative differential transconductance characteristics, was realized by the turn-on of all component FETs, as the current of the FETs increased after PMMA-co-PMAA treatment. The electron-rich carboxyl acid moieties in PMMA-co-PMAA can undergo coordination with the metal Mo or W atoms present in the Se or S vacancies, respectively, resulting in the modulation of charge density. These features yielded distinctive FETs and ternary inverters for MVLCs using cross-type WSe2/MoS2 heterojunctions.
AB - The electrical and optical characteristics of two-dimensional (2D) transition-metal dichalcogenides (TMDCs) can be improved by surface modification. In this study, distinctive field-effect transistors (FETs) were realized by forming cross-type 2D WSe2/MoS2 p-n heterojunctions through surface treatment using poly(methyl methacrylate-co-methacrylic acid) (PMMA-co-PMAA). The FETs were applied to new ternary inverters as multivalued logic circuits (MVLCs). Laser confocal microscope photoluminescence spectroscopy indicated the generation of trions in the WSe2 and MoS2 layers, and the intensity decreased after PMMA-co-PMAA treatment. For the cross-type WSe2/MoS2 p-n heterojunction FETs subjected to PMMA-co-PMAA treatment, the channel current and the region of anti-ambipolar transistor characteristics increased considerably, and ternary inverter characteristics with three stable logic states, "1", "1/2", and "0", were realized. Interestingly, the intermediate logic state 1/2, which results from the negative differential transconductance characteristics, was realized by the turn-on of all component FETs, as the current of the FETs increased after PMMA-co-PMAA treatment. The electron-rich carboxyl acid moieties in PMMA-co-PMAA can undergo coordination with the metal Mo or W atoms present in the Se or S vacancies, respectively, resulting in the modulation of charge density. These features yielded distinctive FETs and ternary inverters for MVLCs using cross-type WSe2/MoS2 heterojunctions.
KW - field-effect transistor
KW - heterojunction
KW - surface treatment
KW - ternary inverter
KW - transition-metal dichalcogenide
UR - http://www.scopus.com/inward/record.url?scp=85089712135&partnerID=8YFLogxK
U2 - 10.1021/acsami.0c09706
DO - 10.1021/acsami.0c09706
M3 - Article
C2 - 32672032
AN - SCOPUS:85089712135
VL - 12
SP - 36530
EP - 36539
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 32
ER -