A Novel pH Sensor of Extended-Gate Field-Effect Transistors With Laser-Irradiated Carbon-Nanotube Network

Yun-Shan Chien, Wan-Lin Tsai, I-Che Lee, Jung-Chuan Chou, Huang-Chung Cheng
2012 IEEE Electron Device Letters  
The extended-gate field-effect transistors (EGFETs) with only the carbon-nanotube (CNT) thin film as both the sensing membrane and the contact electrode have been demonstrated for the first time to exhibit superior pH sensing characteristics. The continuous-wave laser was necessary to improve the pH sensitivity to be 50.9 mV/pH and the linearity values to be 0.9978 for pH = 3 to pH = 13 wide sensing range, respectively. It implied that the laser energy would unzip the chemically modified
more » ... lly modified multiwalled CNTs (MWCNTs) into numerous graphite slices, resulting in the elevated sensing sites and the improved electrical and sensing properties. Therefore, the laser-irradiated MWCNT network is promising for the applications in the flexible and transparent pH-EGFETs. Index Terms-Carbon-nanotube (CNT) network, extendedgate field-effect transistor (EGFET), modified multiwalled carbon nanotube (MWCNT), pH sensor.
doi:10.1109/led.2012.2213794 fatcat:4g6jefhqhvd4pebydcl7zcij2u