Title :
A Novel pH Sensor of Extended-Gate Field-Effect Transistors With Laser-Irradiated Carbon-Nanotube Network
Author :
Chien, Yun-Shan ; Tsai, Wan-Lin ; Lee, I-Che ; Chou, Jung-Chuan ; Cheng, Huang-Chung
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
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 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.
Keywords :
carbon nanotubes; chemical lasers; chemical sensors; electrochemical electrodes; field effect transistors; pH measurement; thin films; CNT thin film; carbon-nanotube thin film; chemically modified multiwalled CNT; contact electrode; continuous-wave laser; extended-gate field-effect transistors; graphite slices; laser-irradiated MWCNT network; laser-irradiated carbon-nanotube network; pH sensor; superior pH sensing characteristics; transparent pH-EGFET; Carbon nanotubes; Chemical lasers; FETs; Sensors; pH measurement; Carbon-nanotube (CNT) network; extended-gate field-effect transistor (EGFET); modified multiwalled carbon nanotube (MWCNT); pH sensor;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2012.2213794
