Nano-porous aluminum oxide membrane as filtration interface for optical gas sensor packaging

Packaging and filtration is critical for photonic gas sensors as they are vulnerable to contaminations of dust and moisture in the ambient air. In this work, we present a prototype of packaging using nano-porous anodized aluminum oxide (AAO) as filtration interface for an optical CO2 gas sensor based on evanescent fields of silicon waveguides. An acrylate-type package housing for the AAO membrane was designed, manufactured and assembled via implementing additive manufacturing technologies including 3D-printing and inkjet printing. Simulation and experimental results for the corresponding package shows a minimal influence of response time while providing a significant filtration performance.