Title :
Silicon bolometer and micro variable infrared filter for CO2 measurement
Author :
Hara, Hitoshi ; Kishi, Naoki ; Iwaoka, Hideto
Author_Institution :
Yokogawa Electr. Corp., Musashino, Japan
Abstract :
We have developed silicon bolometers fabricated on an SOI wafer by bulk micromachining and a micro variable infrared filter, and have investigated CO2 measurement using these elements as an NDIR system. The bolometer has a measured D* (1100 K, 10 Hz, 1 Hz) of 1.1×108 cmHz1/2/W. Two bolometers were combined with a micro variable infrared filter tuned to two different wavelengths: the CO2 absorption band and the reference band. The two-wavelength NDIR system for combining these elements with the conventional infrared source was able to measure the concentration of CO 2 with the measurement reproducibility 3 σ of ±3.6% of the measured value or less between the concentrations of 0 ppm and 5000 ppm
Keywords :
air pollution measurement; bolometers; carbon compounds; gas sensors; micro-optics; micromachining; microsensors; optical fabrication; optical filters; silicon-on-insulator; spectrochemical analysis; CO2; IR gas sensor; SOI wafer; Si; absorption band; bulk micromachining; measurement reproducibility; micro variable infrared filter; microbolometers; multiple layer membrane; nondispersive IR system; reference band; two-wavelength system; Bolometers; Boron; Electric variables measurement; Electromagnetic wave absorption; Gas detectors; Optical films; Optical filters; Silicon; Thermal conductivity; Wavelength measurement;
Conference_Titel :
Optical MEMS, 2000 IEEE/LEOS International Conference on
Conference_Location :
Kauai, HI
Print_ISBN :
0-7803-6257-8
DOI :
10.1109/OMEMS.2000.879664
