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

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.