Transmission enhancement in plasmonic nanohole array for colour imaging applications

Plasmonic colour filters are promising candidate for making colour filters in image sensors. Hexagonally arranged hole array based plasmonic colour filters in aluminium has several advantages for image sensor applications such as polarization insensitivity, CMOS compatibility and fine tuning of colours using a nanometer thick film. However, the hole array based filters are limited by their transmission efficiency (transmittance). This paper presents a new filling scheme of adding optimized extra coaxial holes in hole array to increase the transmittance. The results will have potential applications in CMOS and CCD image sensors, filter wheels, and submicron pixels development.