TY - JOUR
T1 - Temperature Dependence of Sensing Characteristics for OTFT-Based Hydrogen Sensor
AU - Li, Bochang
AU - Lai, P. T.
AU - Tang, W. M.
N1 - Funding Information:
Manuscript received January 9, 2020; accepted February 7, 2020. Date of publication February 28, 2020; date of current version March 24, 2020. This work was supported in part by the Research Grants Council (RGC) of the Hong Kong Special Administrative Region (HKSAR), China under Project PolyU 252013/14E, in part by the Seed Fund for Basic Research under Project 201611159275, and in part by the University Development Fund Nanotechnology Research Institute, University of Hong Kong, under Grant 00600009. The review of this article was arranged by Editor I. Kymissis. (Corresponding authors: P. T. Lai; W. M. Tang.) Bochang Li and P. T. Lai are with the Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong (e-mail: [email protected]; [email protected]).
Publisher Copyright:
© 1963-2012 IEEE.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - An organic thin-film transistor (OTFT)-based hydrogen sensor with palladium (Pd) source/drain (S/D) electrodes as the sensing medium is fabricated, and the effects of operating temperature on its sensing performance are investigated. The sensor exhibits a current decrease upon exposure to hydrogen, and a rapid and reversible H2 response upon the introduction and removal of hydrogen is observed. Heating the sensor changes its electrical characteristics and thus its hydrogen sensitivity. It is found that the effects of temperature on the hydrogen solubility and sticking coefficient of the Pd electrodes are important factors determining the sensitivity at a high temperature of 90 °C, but the temperature dependences of carrier mobility and threshold voltage of the OTFT become dominant at lower temperatures of 60 °C and 30 °C. Moreover, shorter response time is realized at higher operating temperature because higher temperature accelerates the diffusion of H atoms in the Pd electrode. However, the recovery time does not show the same trend due to a reconstruction of the pentacene layer at high operating temperature.
AB - An organic thin-film transistor (OTFT)-based hydrogen sensor with palladium (Pd) source/drain (S/D) electrodes as the sensing medium is fabricated, and the effects of operating temperature on its sensing performance are investigated. The sensor exhibits a current decrease upon exposure to hydrogen, and a rapid and reversible H2 response upon the introduction and removal of hydrogen is observed. Heating the sensor changes its electrical characteristics and thus its hydrogen sensitivity. It is found that the effects of temperature on the hydrogen solubility and sticking coefficient of the Pd electrodes are important factors determining the sensitivity at a high temperature of 90 °C, but the temperature dependences of carrier mobility and threshold voltage of the OTFT become dominant at lower temperatures of 60 °C and 30 °C. Moreover, shorter response time is realized at higher operating temperature because higher temperature accelerates the diffusion of H atoms in the Pd electrode. However, the recovery time does not show the same trend due to a reconstruction of the pentacene layer at high operating temperature.
KW - High temperature
KW - hydrogen sensor
KW - organic thin-film transistor (OTFT)
UR - http://www.scopus.com/inward/record.url?scp=85082847139&partnerID=8YFLogxK
U2 - 10.1109/TED.2020.2973288
DO - 10.1109/TED.2020.2973288
M3 - Journal article
AN - SCOPUS:85082847139
SN - 0018-9383
VL - 67
SP - 1776
EP - 1780
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
IS - 4
M1 - 9018105
ER -