Low thermal stress Mo-AIN-Mo platform for metamaterial based Mid-IR absorber

摘要

We demonstrate a new CMOS compatible metal-dielectric-metal (Mo-AlN-Mo) platform of metamaterial absorber for refractory and narrowband applications at Mid IR. Comparison with the recently reported CMOS compatible plasmonic TiN shows superior reflectivity of Mo thin film at mid IR wavelengths (3-8 μm) while AlN provides large thermal stability and thermal conductivity, mid-to-far IR transparency and both second and third order nonlinear effect and satisfies the matching condition of thermal expansion coefficient with Mo toward minimizing the thermal stress. We demonstrate the proof-of-concept of reducing the thermal stress upto 400 deg. by considering a high stress, CMOS platform of SiO₂. We further report temporal measurement of the resonance intensity and wavelength-shift of the absorber structures and confirm the robust performance of the platform over prolonged heating.