Performance enhancement of bimaterial cantilever focal plane array by metamaterial absorber

This paper presents a novel infrared (IR) focal plane array (FPA) with metamaterial absorber (MMA) integrated to enhance its performance. The FPA consists of bimaterial cantilevers fabricated on a glass substrate by a polyimide (PI) sacrificial layer process, thus allowing the optical readout from back side. This reverse configuration of the incident IR radiation and visible light readout avoids the IR energy loss caused by the silicon substrate compared with previous works. In order to further enhance the IR absorption, MMA was conveniently integrated into the FPA pixels with the gold mirror functioning as the ground plane and SiN_x structural layer as the spacer for MMA at the same time. Performance improvement was verified through a comparative tests of FPAs with and without MMA.