Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites
A novel capacitive humidity sensor based on carbon black/polyimide composites is presented in this paper. The details of the fabrication, sensor characteristics, and effect of the carbon black additive are described. It was confirmed that the polyimide composite filled with a tiny amount of carbon b...
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| Format: | Article |
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MDPI AG
2021-03-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/21/6/1974 |
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| author | Jihong Kim Jang-Hoon Cho Hyung-Man Lee Sung-Min Hong |
| author_facet | Jihong Kim Jang-Hoon Cho Hyung-Man Lee Sung-Min Hong |
| author_sort | Jihong Kim |
| collection | DOAJ |
| description | A novel capacitive humidity sensor based on carbon black/polyimide composites is presented in this paper. The details of the fabrication, sensor characteristics, and effect of the carbon black additive are described. It was confirmed that the polyimide composite filled with a tiny amount of carbon black was suitable for a humidity sensing dielectric. The humidity sensors with three different dielectrics, which were pure polyimide, 0.01 wt% carbon black/polyimide, and 0.05 wt% carbon black/polyimide, were fabricated by a micro-electro-mechanical-system (MEMS) process. As the amount of the carbon black additive increased, the sensitivity of the humidity sensor increased. The humidity sensor with 0.05 wt% of carbon black had a much higher sensitivity of 15.21% (20–80% RH, 0.2535%/% RH) than that of the sensor with pure polyimide, which was 9.73% (0.1622%/% RH). The addition of carbon black also led to an enhancement in the hysteresis and response speed. The hysteresis of the humidity sensor decreased from 2.17 to 1.80% when increasing the amount of the carbon black additive. The response speed of the humidity sensor with 0.05 wt% of carbon black was measured to be ~10% faster than that of the sensor with pure polyimide. The long-term stability of the humidity sensors was demonstrated as well. |
| first_indexed | 2024-03-10T13:20:17Z |
| format | Article |
| id | doaj.art-5fb8a89225be4ffea7a30f52538ef213 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-10T13:20:17Z |
| publishDate | 2021-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-5fb8a89225be4ffea7a30f52538ef2132023-11-21T10:06:15ZengMDPI AGSensors1424-82202021-03-01216197410.3390/s21061974Capacitive Humidity Sensor Based on Carbon Black/Polyimide CompositesJihong Kim0Jang-Hoon Cho1Hyung-Man Lee2Sung-Min Hong3Department of Electrical Engineering, Yeungnam University, Gyeongsan 38541, KoreaSmart Sensor Research Center, Korea Electronics Technology Institute, Seongnam 13509, KoreaSmart Sensor Research Center, Korea Electronics Technology Institute, Seongnam 13509, KoreaSmart Sensor Research Center, Korea Electronics Technology Institute, Seongnam 13509, KoreaA novel capacitive humidity sensor based on carbon black/polyimide composites is presented in this paper. The details of the fabrication, sensor characteristics, and effect of the carbon black additive are described. It was confirmed that the polyimide composite filled with a tiny amount of carbon black was suitable for a humidity sensing dielectric. The humidity sensors with three different dielectrics, which were pure polyimide, 0.01 wt% carbon black/polyimide, and 0.05 wt% carbon black/polyimide, were fabricated by a micro-electro-mechanical-system (MEMS) process. As the amount of the carbon black additive increased, the sensitivity of the humidity sensor increased. The humidity sensor with 0.05 wt% of carbon black had a much higher sensitivity of 15.21% (20–80% RH, 0.2535%/% RH) than that of the sensor with pure polyimide, which was 9.73% (0.1622%/% RH). The addition of carbon black also led to an enhancement in the hysteresis and response speed. The hysteresis of the humidity sensor decreased from 2.17 to 1.80% when increasing the amount of the carbon black additive. The response speed of the humidity sensor with 0.05 wt% of carbon black was measured to be ~10% faster than that of the sensor with pure polyimide. The long-term stability of the humidity sensors was demonstrated as well.https://www.mdpi.com/1424-8220/21/6/1974humidity sensorcapacitive humidity sensorpolyimidecarbon black |
| spellingShingle | Jihong Kim Jang-Hoon Cho Hyung-Man Lee Sung-Min Hong Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites Sensors humidity sensor capacitive humidity sensor polyimide carbon black |
| title | Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites |
| title_full | Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites |
| title_fullStr | Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites |
| title_full_unstemmed | Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites |
| title_short | Capacitive Humidity Sensor Based on Carbon Black/Polyimide Composites |
| title_sort | capacitive humidity sensor based on carbon black polyimide composites |
| topic | humidity sensor capacitive humidity sensor polyimide carbon black |
| url | https://www.mdpi.com/1424-8220/21/6/1974 |
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