Wavelength selective uncooled infrared sensor using triangular-lattice plasmonic absorbers

A wavelength selective uncooled infrared (IR) sensor was developed using triangular-lattice plasmonic absorbers (PLA). The triangular-lattice PLA has a Au-based two-dimensional periodic dimple-array with a triangular lattice, where photons can be manipulated using the spoof surface plasmon. A microelectromechanical system (MEMS)-based uncooled IR sensor with triangular-lattice PLA was fabricated using complementary metal oxide semiconductor (CMOS) and micromachining techniques. Measurement of the spectral responsivity demonstrated that selective enhancement of the responsivity can be achieved and that the detection wavelength of the triangular-lattice PLA was shorter than that of the square-lattice PLA due to the differences in lattice structure.