Fabrication of wiregrid micropolarizers for imaging from visible to infrared wavelengths

There has been growing interest in adding real-time polarimetric imaging functionality to existing infrared focal plane arrays and CMOS/CCD imagers
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. One approach is to fabricate the micropolarizers using wiregrids. Other approaches using bulk polarizers have also been tried
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. The most challenging aspect is the fabrication of the wiregrid micropolarizer array, which requires patterning at the nanoscale. In this work, we examine a novel approach based on a well known process in CMOS technology. We have utilized the Damascene process for metallization to avoid some of the difficulties in patterning high-aspect ratio metal grids.