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

Abstract

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.

Design of a Silicon Photocatalyst for High-Efficiency Photocatalytic Water Splitting

“…As shown in Figure , a heterojunction was formed between Ag 2 S and silicon. The injection of photogenerated carriers into silicon would significantly improve the durability of the photocatalyst . During four cycle experiments, the heterojunction sample almost remains constant photocatalytic H 2 evolution (Figure ).…”

Ultranarrow Band UV Detection in GaN with Simple Device Architecture

“…Wavelength-selective ultraviolet (UV) photodetectors (PDs) with high spectral selectivity and narrow full-width at half-maxima (FWHM) are highly desired for wide applications, including flame sensors, selected-wavelength imaging, military, fluorescence detection, UV phototherapy, etc. [1][2][3] Here, light with a specific range of wavelength needs to be detected while the background or environmental radiation needs to be suppressed. [4] For instance, in biophotonics, narrow band detectors are crucial for laser-induced fluorescence detection of hazardous airborne pathogens and discriminating between biological and nonbiological particles in real time.…”

High-responsivity hybrid α-Ag2S/Si photodetector prepared by pulsed laser ablation in liquid

“…Recently, Kang et al synthesized monodisperse Ag 2 S NPs by using a sonochemical method and fabricated photodetector devices by integrating Ag 2 S NPs on a graphene sheet [ 17 ]. Tretyakov et al [ 18 ] reported the characterization of a Ag 2 SQD (quantum dots)/Si heterojunction photodetector used for short-wave infrared radiation fabricated by a chemical method. They show that the Ag 2 S quantum dots (QDs) planted on the surface of Si create impurity states in the Si bandgap.…”