Development of a MEMS hotplate-based photoacoustic CO₂ sensor

Instead of the conventional use micro-electro-mechanical system (MEMS) hotplate for metal oxide semiconductor (MOS) or nondispersive infrared (NDIR) gas sensing, it was used photoacoustic (PA) sensing. A low-cost MEMS microphone development this PA carbon dioxide (CO 2 ) sensor. To knowledge authors, is first time that a and are combined in sensing with high modulation frequency. NDIR sensors much more expensive photodetectors compared to work. The have desired characteristics low power consumption, small size cost. as blackbody good emitter which suitable CO detection around 4.26 µm absorption band. Despite significant radiation loss due frequency, remaining/reduced still sufficient excite molecules signal generation. Temperature analysis on sensor showed decreases an increase temperature, implies compensation must be provided such temperature effects. This work provides alternative optical comparatively inexpensive by using components can easily mass-produced, thereby making valuable contribution fight against air pollution global warming.