Imagers that operate in the near-infrared region (wavelengths of 0.7–1.4 µm) are of use in applications such as material sorting, machine vision and autonomous driving. However, such imagers typically use the flip-chip method to connect infrared photodiodes with silicon-based readout integrated circuits, as the need for high-temperature processing and single-crystalline substrates prevents direct integration. This increases processing complexity and cost. Here we report high-resolution imagers that monolithically integrate near-infrared colloidal quantum dot photodiodes with complementary metal–oxide–semiconductor readout integrated circuits. The colloidal quantum dot photodetector is designed with a structure compatible with complementary metal–oxide–semiconductors and exhibits a spectral range of 400–1,300 nm, room-temperature detectivity of 2.1 × 1012 Jones, −3 dB bandwidth of 140 kHz and linear dynamic range of over 100 dB. With this approach, we create a large (640 × 512 pixels) imager that exhibits a spatial resolution of 40 line pairs per millimetre at a modulation transfer function of 50%, and we show that it can be used for vein imaging and matter identification.
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Source data are provided with this paper. The data that support the findings of this study are available from the corresponding authors upon reasonable request.
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This work was financially supported by the National Key Research and Development Program of China (2021YFA0715500; J.T.), National Natural Science Foundation of China (61725401; J.T. and 61904065; L.G.) and Fund for Innovative Research Groups of the Natural Science Foundation of Hubei Province (2020CFA034; J.T.). We thank the Analytical and Testing Center of HUST and the facility support of the Center for Nanoscale Characterization and Devices (CHCB), WNLO-HUST. We appreciate helpful discussions from Hao Li and Prof. Dongsheng Liu.
The authors declare no competing interests.
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Liu, J., Liu, P., Chen, D. et al. A near-infrared colloidal quantum dot imager with monolithically integrated readout circuitry. Nat Electron 5, 443–451 (2022). https://doi.org/10.1038/s41928-022-00779-x