Scalable Fabrication of Infrared Detectors with Multispectral Photoresponse Based on Patterned Colloidal Quantum Dot Films

Abstract

Colloidal quantum dots (CQDs) are promising materials for developing infrared (IR) detectors. Absorption spectra and spectral photoresponse can be continuously tuned by controlling the size, shape, and composition of CQDs. However, the incapability to achieve site-selective patterning of CQDs by conventional methods (i.e., drop casting, spin coating, and spray coating) greatly hinders the realization of CQD-based multipixel or multispectral detectors. In this paper, we demonstrate a simple and highly efficient poly­(methyl methacrylate)-assisted transfer technique for the scalable fabrication of CQD-based photodetectors with multiple pixels, which respond to different spectral ranges of IR, by using patterned HgTe CQD films. Large arrays of three-pixel photodetectors were produced on both flat and curved substrates with a high fabrication success rate of over 95%. The maximum room-temperature responsivity of up to 0.1 A/W under low operation voltage (<10 V) was achieved. Furthermore, a spectral photodetector was fabricated, and an IR spectrum ranging from 2 to 10 μm was successfully reconstructed. The proposed fabrication method acted as a reliable approach for manufacturing high-performance photodetector arrays for applications in multicolor focal plane cameras and microspectrometers.

HgTe Nanocrystal Inks for Extended Short‐Wave Infrared Detection

“…Later, it was proposed to add a unipolar barrier which had the purpose to selectively decrease the electron dark current. Room temperature detectivity up to 3 × 10 8 Jones has been demonstrated . In this device, the performance remains clearly limited by the low responsivity (100 µA W −1 at 0 V) rather than by the signal/noise ratio.…”

“…On the other hand, efforts dedicated to the integration of HgTe nanocrystals into photodiodes are much fewer than those reported for PbS. As a result, most devices based on HgTe nanocrystals with long wavelength absorption are based on planar geometries …”

High-Performance Ultraviolet Photodetector Based on Graphene Quantum Dots Decorated ZnO Nanorods/GaN Film Isotype Heterojunctions

“…Accordingly, the maximum detectivity up to 10 12 Jones has been achieved, which is higher than that of the photodetectors based on most ZnO photodetectors [38, 39]. The employment of GQDs as the light absorbers and electron donors could attribute to enhancement of carrier concentration in heterogeneous junction, thus greatly improving the responsivity and detectivity of the UV photodetectors.…”

Designing Photovoltaic Devices Using HgTe Nanocrystals for Short and Mid‐Wave Infrared Detection

“…Recent device developments include the demonstration of HgTe‐based field‐effect transistor and phototransistor, introduction of resonators to enhance the device light absorption, achieve pixel‐level spectral filtering or to achieve polarization‐sensitive detector . Devices with multicolor detection have been demonstrated either in the visible and in the IR, or in different IR fields such as SWIR/MWIR and MWIR/LWIR . Thanks to the narrow bandgap nature of the material, the use of multi exciton generation becomes possible at relatively low photon energy .…”

“…[39] Devices with multicolor detection have been demonstrated either in the visible and in the IR, [40] or in different IR fields such as SWIR/MWIR [41] and MWIR/LWIR. [42] Thanks to the narrow bandgap nature of the material, the use of multi exciton generation becomes possible at relatively low photon energy. [43][44][45] Integration of the material is no longer limited to a single pixel in planar geometry.…”