nAnalysis of subwavelength metal hole array structure for the enhancement of back-illuminated quantum dot infrared photodetectors

Abstract

This paper is focused on analyzing the impact of a two-dimensional metal hole array structure integrated to the back-illuminated quantum dots-in-a-well (DWELL) infrared photodetectors. The metal hole array consisting of subwavelength-circular holes penetrating gold layer (2D-Au-CHA) provides the enhanced responsivity of DWELL infrared photodetector at certain wavelengths. The performance of 2D-Au-CHA is investigated by calculating the absorption of active layer in the DWELL structure using a finite integration technique. Simulation results show that the performance of the DWELL focal plane array (FPA) is improved by enhancing the coupling to active layer via local field engineering resulting from a surface plasmon polariton mode and a guided Fabry-Perot mode. Simulation method accomplished in this paper provides a generalized approach to optimize the design of any type of couplers integrated to infrared photodetectors. Experimental results demonstrate the enhanced signal-to-noise ratio by the 2D-Au-CHA integrated FPA as compared to the DWELL FPA. A comparison between the experiment and the simulation shows a good agreement.

Plasmonic Superpixel Sensor for Compressive Spectral Sensing

“…As reported in our earlier work [7], [8], employing plasmonic structures results in significant near-field enhancement of electric fields, which enables increased photon absorption at the active layer of focal plane array (FPA). In addition, the structural tuning of the plasmonic architecture (i.e., geometry of plasmonic pattern) that is integrated with IR FPA (which is one of the backside-illumination devices) allows for the spectral responsivity of the detector to be modified (e.g., bandwidth and peak wavelength).…”

“…The sensing system is comprised of a single focal plane to acquire informationrich data to extract and discriminate targets from a single data set. To realize such a sensor, we intend to develop a superpixel array incorporating plasmonic modification [7]- [11] and compressive spectral sensing (CSS) [6], [12]- [15]. The concept is described as follows.…”

Simulation and analysis of grating-integrated quantum dot infrared detectors for spectral response control and performance enhancement

“…In our simulation, we model this active layer as an 1120 nm thick effective absorber whose anisotropic dielectric constants are taken from the literature. 28,29 We use the anisotropic dielectric constants to account for the different absorption efficiencies of QDs into x (or y) and z directions. The QD absorption covers the mid-IR range of 4-8 lm.…”

Design principle of Au grating couplers for quantum-well infrared photodetectors

“…Inspired by the research of extraordinary optical transmission [8], planar plasmonic structures have recently been applied to improve the performance of infrared photodetectors [9][10][11][12][13][14]. By placing a metallic grating on the surface of detector, the efficiency of detection can be enhanced at plasmonic resonant wavelengths.…”

“…Such a structure is much easier to fabricate compared with those of double metallic layers [15][16][17]. However, these studies are focused mainly on QDIPs and only a few studies have been done for QWIPs [9][10][11][12][13][14].…”