TY - JOUR
T1 - Sensitivity evolution and enhancement mechanism of porous anodic aluminum oxide humidity sensor using magnetic field
AU - Chen, S. W.
AU - Khor, O. K.
AU - Liao, M. W.
AU - Chung, C. K.
N1 - Funding Information:
This work is partially sponsored by National Science Council under contract Nos NSC99-2221-E-006-032-MY3 and NSC101-2628-E-006-012-MY3. We also would like to thank the Center for Micro/Nano Science and Technology in National Cheng Kung University for analysis instrument support.
PY - 2014/8
Y1 - 2014/8
N2 - Capacitive sensors based on anodic oxide aluminum (AAO) film provide a fast and reliable means of sensing humidity. Moreover, the water molecules under a magnetic field preferentially form water clusters in which the dipole moments of the water molecules have a more orderly arrangement. In this article, we have investigated the sensitivity enhancement and its mechanism of the AAO humidity sensor by performing the sensing operation in the presence of an NbFeB magnet. The results show that the application of a magnetic field with a strength of 0.058 T yields a linear-like relationship between the capacitance and the relative humidity (RH) even under low RH of 25-45%. The sensitivity performance at low-to-high RH conditions arises because the magnetic field leads to a more orderly arrangement of the water molecules in the pores of the AAO film so as to increase the dielectric constant. Thus, the proposed method and mechanism suggest significant potential for enhancing the sensitivity and linearity of the capacitive AAO sensor from low-to-high RH.
AB - Capacitive sensors based on anodic oxide aluminum (AAO) film provide a fast and reliable means of sensing humidity. Moreover, the water molecules under a magnetic field preferentially form water clusters in which the dipole moments of the water molecules have a more orderly arrangement. In this article, we have investigated the sensitivity enhancement and its mechanism of the AAO humidity sensor by performing the sensing operation in the presence of an NbFeB magnet. The results show that the application of a magnetic field with a strength of 0.058 T yields a linear-like relationship between the capacitance and the relative humidity (RH) even under low RH of 25-45%. The sensitivity performance at low-to-high RH conditions arises because the magnetic field leads to a more orderly arrangement of the water molecules in the pores of the AAO film so as to increase the dielectric constant. Thus, the proposed method and mechanism suggest significant potential for enhancing the sensitivity and linearity of the capacitive AAO sensor from low-to-high RH.
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U2 - 10.1016/j.snb.2014.03.057
DO - 10.1016/j.snb.2014.03.057
M3 - Article
AN - SCOPUS:84899623917
SN - 0925-4005
VL - 199
SP - 384
EP - 388
JO - Sensors and Actuators, B: Chemical
JF - Sensors and Actuators, B: Chemical
ER -