Room Temperature Silicon Detector for IR Range Coated with Ag2S Quantum Dots

• Published in: Physica status solidi. PSS-RRL. Rapid research letters 2019-09, Vol.13 (9), p.n/a
• Main Authors: Tretyakov, Ivan, Shurakov, Alexander, Perepelitsa, Alexey, Kaurova, Natalya, Svyatodukh, Sergey, Zilberley, Tatyana, Ryabchun, Sergey, Smirnov, Mikhail, Ovchinnikov, Oleg, Goltsman, Gregory
• Format: Article
• Language: English
• Subjects: Energy gap; Impurities; infrared detectors; Optoelectronic devices; Organic chemistry; Photon absorption; Photons; Quantum dots; Room temperature; room-temperature detection, short-wavelength infrared, Si-based devices; Silicon; surface states
• ISSN: 1862-6254; 1862-6270
• DOI: 10.1002/pssr.201900187

For decades, silicon has been the chief technological semiconducting material of modern microelectronics and has a strong influence on all aspects of the society. Applications of Si‐based optoelectronic devices are limited to the visible and near infrared (IR) ranges. For photons with an energy less than 1.12 eV, silicon is almost transparent. The expansion of the Si absorption to shorter wavelengths of the IR range is of considerable interest for optoelectronic applications. By creating impurity states in Si, it is possible to cause sub‐bandgap photon absorption. Herein, an elegant and effective technology of extending the photo‐response of Si toward the IR range is presented. This approach is based on the use of Ag2S quantum dots (QDs) planted on the surface of Si to create impurity states in the Si bandgap. The specific sensitivity of the room temperature zero‐bias Si_Ag2S detector is 1011 cm √Hz W−1 at 1.55 μm. Given the variety of available QDs and the ease of extending the photo‐response of Si toward the IR range, these findings open a path toward future studies and development of Si detectors for technological applications. The current research at the interface of physics and chemistry is also of fundamental importance to the development of Si optoelectronics. The expansion of the silicon absorption to shorter wavelengths of the infrared range is of considerable interest for optoelectronic applications. It is possible by creating impurity states in Si by Ag2S quantum dot coating for sub‐bandgap IR photon absorption. The specific sensitivity of the room temperature Si_Ag2S detector is 1011 cm √Hz W−1 at 1.55 μm.