CO2Gas Sensing By Cmos-Mems Scaln-Based Pyroelectric Detector Based on MID-IR Absorption

Abstract

CO2 gas sensing responses are measured using our in-house fabricated CMOS-MEMS ScAlN-based pyroelectric detector with 12% Sc doped concentration. Leveraging on mid-IR absorption behavior of CO2 gas caused by interaction of CO2 with light at 4.26 µm wavelength, our ScAlN-based pyroelectric detector successfully detect CO2 gas response ranging from CO2 concentrations of 5000 ppm down to 200 ppm. Gas channel lengths are varied from 6 cm to 10 cm and their respective CO2 responses are measured. Finally, with N2 as the reference gas, we calculate the gas response percentage change of CO2 gas at different gas channel lengths and concentration.