Ag₂S QDs/Si Heterostructure-Based Ultrasensitive SWIR Range Detector

• Main Authors: Ivan Tretyakov, Sergey Svyatodukh, Aleksey Perepelitsa, Sergey Ryabchun, Natalya Kaurova, Alexander Shurakov, Mikhail Smirnov, Oleg Ovchinnikov, Gregory Goltsman
• Format: Article
• Language: English
• Published: MDPI AG 2020-04-01
• Series: Nanomaterials
• Subjects: short-wave infrared range; silicon; quantum dots; detector
• Online Access: https://www.mdpi.com/2079-4991/10/5/861

<b> </b>In the 20^th century, microelectronics was revolutionized by silicon—its semiconducting properties finally made it possible to reduce the size of electronic components to a few nanometers. The ability to control the semiconducting properties of Si on the nanometer scale promises a breakthrough in the development of Si-based technologies. In this paper, we present the results of our experimental studies of the photovoltaic effect in Ag₂S QD/Si heterostructures in the short-wave infrared range. At room temperature, the Ag₂S/Si heterostructures offer a noise-equivalent power of 1.1 × 10⁻¹⁰ W/√Hz. The spectral analysis of the photoresponse of the Ag₂S/Si heterostructures has made it possible to identify two main mechanisms behind it: the absorption of IR radiation by defects in the crystalline structure of the Ag₂S QDs or by quantum QD-induced surface states in Si. This study has demonstrated an effective and low-cost way to create a sensitive room temperature SWIR photodetector which would be compatible with the Si complementary metal oxide semiconductor technology.