Wavelength selective wideband uncooled infrared sensor using a two-dimensional plasmonic absorber

Abstract

Abstract. A wavelength selective wideband uncooled infrared (IR) sensor that detects middle-wavelength and long-wavelength IR (MWIR and LWIR) regions has been developed using a two-dimensional plasmonic absorber (2-D PLA). The 2-D PLA has a Au-based 2-D periodic dimple-array structure, where photons can be manipulated using a spoof surface plasmon. Numerical investigations demonstrate that the absorption wavelength can be designed according to the surface period of dimples over a wide wavelength range (MWIR and LWIR regions). A microelectromechanical system-based uncooled IR sensor with a 2-D PLA was fabricated using complementary metal oxide semiconductor and micromachining techniques. Measurement of the spectral responsivity shows that the selective enhancement of responsivity is achieved over both MWIR and LWIR regions, where the wavelength of the responsivity peak coincides with the dimple period of the 2-D PLA. The results provide direct evidence that a wideband wavelength selective IR sensor can be realized simply by design of the 2-D PLA surface structure without the need for vertical control in terms of gap or thickness. A pixel array where each pixel has a different detection wavelength could be developed for multicolor IR imaging.

Wavelength- or Polarization-Selective Thermal Infrared Detectors for Multi-Color or Polarimetric Imaging Using Plasmonics and Metamaterials

“…The periodic lattice structures define the absorption wavelength that controls the propagating surface plasmon resonance [41,42,43,44,45,46,47]. Such two-dimensional plasmonic absorbers (2D-PAs) have the advantages of simple fabrication and robustness of structural fluctuations, such as the dimple size and depth.…”

“…Figure 3a,b show the concept of pixel integration in an array format with wavelength or polarization selectivity using PMAs for multi-color [42] and polarimetric imaging [44], respectively. Figure 3a shows the concept of PMAs with various surface pixel array structures, where three different PMAs with different absorption wavelengths (λ1, λ2, and λ3) are employed.…”

“…We have developed wavelength-selective uncooled IR sensors using Au-based 2D-PAs [41,42,43,45]. A thermopile was used for the uncooled IR sensor.…”

“…A thermopile was used for the uncooled IR sensor. Figure 4a,b show a schematic diagram and a scanning electron microscopy (SEM) image, respectively [41,42], of our developed wavelength-selective uncooled IR sensors using 2D-PAs with a square lattice. The fabrication procedure employed the conventional complimentary-metal-oxide-semiconductor (CMOS) process and a bulk micromachining technique.…”

Enhancing the Responsivity of Uncooled Infrared Detectors Using Plasmonics for High-Performance Infrared Spectroscopy

“…Although the significant losses associated with their propagation hindered their wide use for many applications [18,19], they can be exploited to enhance the performance of IR detectors by enhancing the absorption of IR radiation. Thus, SPPs have been recently employed to enhance the responsivity of IR detectors [3,20,21,22]. …”