WORKSHOP PAPER
Detailed Characterization of SWIR-sensitive Colloidal Quantum Dot Image Sensors
Abstract
Due to the weak responsivity of silicon imagers to photons with lower energy than 1.12 eV, thin-film image sensors are increasingly considered as potential alternatives. This study emphasizes the notable performance of lead sulfide (PbS) Colloidal Quantum Dot (CQD) photodetectors, highlighting their absorption wavelength tunability up to 2.6 µm and compatibility with CMOS processes. It presents detailed analyses of PbS CQD imagers, focusing on their exceptional shot-noise-limited behavior and Short-Wavelength-Infrared (SWIR) sensitivity, achieving an External Quantum Efficiency (EQE) of up to 40% at 1450 nm wavelength. The paper also discusses operation speed through image lag characterization, blooming suppression techniques, and the statistical analysis of activation energy for quantum dots using dark current spectroscopy.Keywords
Thin-film imager, PbS Colloidal Quantum Dot photodiode, SWIR-sensitive,References
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