Symmetric Metamaterial Antenna to Improve Responsivity of CMOS-MEMS Thermoelectric Infrared Sensors

This study extends the surface metal-insulator-metal (MIM) absorber design in [1] to propose an the MIM absorber embedded in SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> for a CMOS-MEMS thermoelectric (TE) infrared (IR) sensor (Fig.1), implemented using the TSMC 0.35μm 2P4M standard CMOS process. The sensor features an array of metamaterial structures, formed by the symmetric metallic antenna and metallic reflector which embedded inside the SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> absorption layers. The TE IR sensor developed in this study is designed to enhance the absorption in the long-wavelength infrared region (8-14μm), making it suitable for human detection applications. The FTIR spectral absorption analysis demonstrates that the absorption layer incorporating metamaterials significantly enhances absorption in the target wavelength range. Furthermore, measurement results reveal that the symmetric (proposed) design shows an improvement in responsivity of 6.3% compared to the SiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> design.