Short‐Wave Infrared Photodetectors and Imaging Sensors Based on Lead Chalcogenide Colloidal Quantum Dots

Abstract

Lead chalcogenide quantum dots (QDs) are one of the next generations of ideal narrow bandgap infrared semiconductors, due to their succinct solution processing, low‐cost fabrication, size‐tunable infrared bandgap, and excellent optoelectronic properties. Tremendous efforts including synthesis methods, surface ligand engineering, and device architecture engineering, drastically contribute to the significant improvement of the performance of the photodetectors based on QDs. In recent years, with the rapid development of consumer electronics, short‐wave infrared (SWIR) imaging sensors are in urgent demand. Thanks to the flexible manipulation of the QD thin film deposition process, a variety of QD‐based imaging technologies have been studied, including single‐pixel imaging sensors, integrated imaging sensors with readout circuit, and upconversion imaging sensors, which can effectively reduce the cost of SWIR imaging sensors and promote the commercial application in the consumer electronics. Herein, recent advances of QD‐based photodetectors and imaging sensors are summarized, emphatically focusing on the synthesis of QDs, surface ligand engineering, device architecture engineering, and imaging technology.

Scaling of Hybrid QDs-Graphene Photodetectors to Subwavelength Dimensions

“…In contrast to printing, the entire sample was covered with one cQD thickness (inset). The LbL spin coating has been proven to yield dense and crack-free conductive films, optimally suited for solar cells and photodetectors. − …”

In Situ Room-Temperature Synthesis of All-Colloidal Quantum Dot CsPbBr3–PbS Heterostructures

“…The successful construction of all-CQD heterostructures and their efficient carrier transfer have enhanced the optical response of PbS QDs in the ultraviolet–visible (UV–vis) range and the fluorescence in the NIR region, opening up possibilities for their application in high-performance short-wavelength infrared (SWIR) imaging. The SWIR technology based on chalcogenide QDs has been already reported. ,− In general, this technology primarily relies on expensive infrared lasers as light sources . Here, we made the first attempt to explore SWIR imaging using low-cost processing all-CQD CsPbBr 3 –PbS heterostructures with UV light source.…”

Recent Advances and Challenges of Colloidal Quantum Dot Light‐Emitting Diodes for Display Applications

“…Over the past decades, colloidal quantum dot (QD) has become one of the most attractive technologies in optoelectronics, [1,2] such as photovoltaics, [3] photodetectors, [4] lasers, [5] lightings, [6,7] and primarily displays. [8,9] QDs are nanometer-sized spherical semiconductor clusters in which the quantum confinement regime specifies the wave function of the electrons and holes.…”