School of Mechanical Engineering, Yonsei University, 262 Seongsanno, Seodaemun-gu, Seoul 120-749, Republic of Korea.
Nanotechnology. 2010 Mar 12;21(10):105502. doi: 10.1088/0957-4484/21/10/105502. Epub 2010 Feb 15.
A pressure and flow sensor based on the electrothermal-thermistor effect of a batch-processed carbon nanotube wall (CNT wall) is presented. The negative temperature coefficient of resistance (TCR) of CNTs and the temperature dependent tunneling rate through the CNT/silicon junction enable vacuum pressure and flow velocity sensing because the heat transfer rate between CNTs and the surrounding gas molecules differs depending on pressure and flow rate. The CNT walls are synthesized by thermal chemical vapor deposition (CVD) on an array of microelectrodes fabricated on a silicon-on-insulator (SOI) wafer. The CNTs are self-assembled between the microelectrodes and substrate across the thickness of a buried oxide layer during the synthesis process, and the simple batch fabrication results in high throughput and yield. A wide pressure range, down to 3 x 10(-3) from 10(5) Pa, and a nitrogen flow velocity range between 1 and 52.4 mm s(-1), are sensed. Further experimental characterizations of the bias voltage dependent response of the sensor as a vacuum pressure gauge are presented.
提出了一种基于批量处理碳纳米管壁（CNT 壁）电热-热敏电阻效应的压力和流量传感器。由于 CNT 与周围气体分子之间的传热速率取决于压力和流速，因此 CNT 的负电阻温度系数（TCR）和通过 CNT/硅结的温度相关隧穿速率使真空压力和流速感测成为可能。CNT 壁通过在绝缘体上硅（SOI）晶片上制造的微电极阵列上的热化学气相沉积（CVD）合成。在合成过程中，CNTs 在电极和衬底之间自组装，跨越埋氧层的厚度，简单的批量制造可实现高产量和高良率。该传感器可检测到宽的压力范围，从 3 x 10(-3) 到 10(5) Pa，以及氮气流速范围在 1 到 52.4 mm s(-1) 之间。进一步展示了作为真空压力表的传感器的偏置电压相关响应的实验特性。
