Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors
Carbon nanotubes (CNTs) are promising materials for gas sensing because of their large specific area and high sensitivity to charge differentiation. In CNT-based field-effect transistors (FETs) for gas sensing, both CNT potential modulation in the channels and Schottky barrier height modulation at t...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2022-12-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/5.0124891 |
| _version_ | 1828058395082489856 |
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| author | Shota Nakahara Takahiro Morita Haruka Omachi Masafumi Inaba Michihiko Nakano Junya Suehiro |
| author_facet | Shota Nakahara Takahiro Morita Haruka Omachi Masafumi Inaba Michihiko Nakano Junya Suehiro |
| author_sort | Shota Nakahara |
| collection | DOAJ |
| description | Carbon nanotubes (CNTs) are promising materials for gas sensing because of their large specific area and high sensitivity to charge differentiation. In CNT-based field-effect transistors (FETs) for gas sensing, both CNT potential modulation in the channels and Schottky barrier height modulation at the CNT/metal electrode contact influence the current properties. However, researchers have not used Schottky barrier height modulation for gas detection. To investigate and compare the effects of Schottky barrier height modulation and CNT channel potential modulation on NO2 gas exposure, we fabricated ambipolar CNT FETs by the dielectrophoretic assembly. We exposed CNT FET gas sensors to N2 gas containing 100-ppb NO2 and observed two different responses in the electric properties: a steady current shift in the positive direction in the hole-conduction region because of the channel potential modulation, and an abrupt decrease in transconductance in the electron-conduction region because of the Schottky barrier modulation. The CNT channels and CNT/metal contact both contributed to the sensor response, and the modulation rate of the Schottky barrier was higher than that of the CNT potential shift in the channel. |
| first_indexed | 2024-04-10T21:26:32Z |
| format | Article |
| id | doaj.art-d4d62171da8248b6a04d52a92d629a10 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-04-10T21:26:32Z |
| publishDate | 2022-12-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-d4d62171da8248b6a04d52a92d629a102023-01-19T16:47:10ZengAIP Publishing LLCAIP Advances2158-32262022-12-011212125302125302-610.1063/5.0124891Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistorsShota Nakahara0Takahiro Morita1Haruka Omachi2Masafumi Inaba3Michihiko Nakano4Junya Suehiro5Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, JapanGraduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, JapanIntegrated Research Consortium on Chemical Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, JapanFaculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, JapanFaculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, JapanFaculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, JapanCarbon nanotubes (CNTs) are promising materials for gas sensing because of their large specific area and high sensitivity to charge differentiation. In CNT-based field-effect transistors (FETs) for gas sensing, both CNT potential modulation in the channels and Schottky barrier height modulation at the CNT/metal electrode contact influence the current properties. However, researchers have not used Schottky barrier height modulation for gas detection. To investigate and compare the effects of Schottky barrier height modulation and CNT channel potential modulation on NO2 gas exposure, we fabricated ambipolar CNT FETs by the dielectrophoretic assembly. We exposed CNT FET gas sensors to N2 gas containing 100-ppb NO2 and observed two different responses in the electric properties: a steady current shift in the positive direction in the hole-conduction region because of the channel potential modulation, and an abrupt decrease in transconductance in the electron-conduction region because of the Schottky barrier modulation. The CNT channels and CNT/metal contact both contributed to the sensor response, and the modulation rate of the Schottky barrier was higher than that of the CNT potential shift in the channel.http://dx.doi.org/10.1063/5.0124891 |
| spellingShingle | Shota Nakahara Takahiro Morita Haruka Omachi Masafumi Inaba Michihiko Nakano Junya Suehiro Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors AIP Advances |
| title | Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors |
| title_full | Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors |
| title_fullStr | Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors |
| title_full_unstemmed | Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors |
| title_short | Comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field-effect transistors |
| title_sort | comparison between modulations of contact and channel potential in nitrogen dioxide gas response of ambipolar carbon nanotube field effect transistors |
| url | http://dx.doi.org/10.1063/5.0124891 |
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