MEMS红外微辐射源的研制及应用

micro thermal emitter based on electrically heated thin film has been studied for non-dispersive infrared gas sensor as a infrared source The IR source, with effectively emitting area of 2.0*2.0 mm2, is obtained from heated platinum thin film resistors that deposit on a Si3N4/SiO2 suspended membrane. IR radiation power of the emitter is up to 60mW and the energy efficiency ratio reaches 10.9% with the effective blackbody temperature ranged from 300 to 850K. Moreover, it shows very good dynamic parameters with a modulation frequency as high as 100Hz and response time 18.3ms, which make it suitable for fast NDIR measurements of concentration. It has been proven that the emitter can sever as a stable IR source in Non-dispersive infrared (NDIR) gas sensor. The NDIR used the microemitter has acceptable sensitivity and rapid response time with detection limits of 20ppm and 50ppm level for CO2 and SO2 respectively.