Carrier-Type Modulation and Mobility Improvement of Thin MoTe2
© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
| Veröffentlicht in: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 29(2017), 39 vom: 07. Okt. |
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| Weitere Verfasser: | , , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2017
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| Zugriff auf das übergeordnete Werk: | Advanced materials (Deerfield Beach, Fla.) |
| Schlagworte: | Journal Article MoTe2 controllable doping mobility improvement unipolar transistors |
| Zusammenfassung: | © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. A systematic modulation of the carrier type in molybdenum ditelluride (MoTe2 ) field-effect transistors (FETs) is described, through rapid thermal annealing (RTA) under a controlled O2 environment (p-type modulation) and benzyl viologen (BV) doping (n-type modulation). Al2 O3 capping is then introduced to improve the carrier mobilities and device stability. MoTe2 is found to be ultrasensitive to O2 at elevated temperatures (250 °C). Charge carriers of MoTe2 flakes annealed via RTA at various vacuum levels are tuned between predominantly pristine n-type ambipolar, symmetric ambipolar, unipolar p-type, and degenerate-like p-type. Changes in the MoTe2 -transistor performance are confirmed to originate from the physical and chemical absorption and dissociation of O2 , especially at tellurium vacancy sites. The electron branch is modulated by varying the BV dopant concentrations and annealing conditions. Unipolar n-type MoTe2 FETs with a high on-off ratio exceeding 106 are achieved under optimized doping conditions. By introducing Al2 O3 capping, carrier field effect mobilities (41 for holes and 80 cm2 V-1 s-1 for electrons) and device stability are improved due to the reduced trap densities and isolation from ambient air. Lateral MoTe2 p-n diodes with an ideality factor of 1.2 are fabricated using the p- and n-type doping technique to test the superb potential of the doping method in functional electronic device applications |
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| Beschreibung: | Date Completed 18.07.2018 Date Revised 30.09.2020 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1521-4095 |
| DOI: | 10.1002/adma.201606433 |