Title :
An alpha-alumina moisture sensor for relative and absolute humidity measurement
Author :
Chen, Zhi ; Jin, Mao-Chang
Author_Institution :
Dept. of Mater. Sci. & Eng., Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
A novel humidity sensor using an alpha -alumina porous film has been developed for moisture analysis as well as relative humidity measurement. The humidity sensing dielectric used for the sensor mainly consists of a cylindrical-pore-like alpha -alumina film formed by anodic spark deposition, with a dense amorphous alumina thin barrier layer at the pore base formed by reanodization. The performance characteristics of the sensor, e.g., humidity sensitivity, humidity hysteresis, temperature dependence, response time, reproducibility, and long-term calibration stability, were studied in detail. It was found that the sensor can be used for absolute humidity detection in the range from -80 degrees C to -10 degrees C frost point as well as for relative humidity (RH) measurement from 10% to 100% RH with very stable performance.<>
Keywords :
alumina; electric sensing devices; humidity measurement; -80 to -10 degC; Al/sub 2/O/sub 3/; absolute humidity; anodic spark deposition; barrier layer; calibration stability; dielectric; hysteresis; measurement; moisture sensor; performance characteristics; reanodization; relative humidity; reproducibility; response time; sensitivity; temperature dependence; Amorphous materials; Dielectric thin films; Humidity measurement; Hysteresis; Moisture; Sensor phenomena and characterization; Sparks; Temperature dependence; Temperature sensors; Thin film sensors;
Conference_Titel :
Industry Applications Society Annual Meeting, 1992., Conference Record of the 1992 IEEE
Conference_Location :
Houston, TX, USA
Print_ISBN :
0-7803-0635-X
DOI :
10.1109/IAS.1992.244236