Title :
pH Sensing Characteristics of Extended-Gate Field-Effect Transistor Based on Al-Doped ZnO Nanostructures Hydrothermally Synthesized at Low Temperatures
Author :
Yang, Po-Yu ; Wang, Jyh-Liang ; Chiu, Po-Chun ; Chou, Jung-Chuan ; Chen, Cheng-Wei ; Li, Hung-Hsien ; Cheng, Huang-Chung
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
The pH sensing properties of an extended-gate field-effect transistor (EGFET) with Al-doped ZnO (AZO) nanostructures are investigated. The AZO nanostructures with different Al dosages were synthesized on AZO/glass substrate via a simple hydrothermal growth method at 85°C . The pH sensing characteristics of pH-EGFET sensors with an Al dosage of 1.98 at% can exhibit a higher voltage sensitivity of 57.95 mV/pH, a larger linearity of 0.9998, and a wide sensing range of pH 1-13, attributed to the well-aligned nanowire (NW) array, superior crystallinity, less structural defects, and better conductivity. Consequently, the hydrothermally grown AZO NWs demonstrate superior pH sensing characteristics and reveal the potentials for flexible and disposable biosensors.
Keywords :
II-VI semiconductors; aluminium; chemical sensors; crystal defects; electrical conductivity; field effect transistors; nanoelectronics; nanowires; pH measurement; wide band gap semiconductors; zinc compounds; EGFET; ZnO:Al; conductivity; crystallinity; disposable biosensors; doped nanostructures; extended-gate field-effect transistor; flexible biosensors; glass substrate; hydrothermal growth; nanowire array; pH sensing; structural defects; temperature 85 degC; Conductivity; Electrodes; Nanostructures; Sensitivity; Sensors; Substrates; Zinc oxide; Al-doped zinc oxide (AZO); extended-gate field-effect transistor (EGFET); hydrothermal method; low temperature;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2011.2164230
