Visible electroluminescence from nanostructured silicon-based Schottky junction LED: role of metal contacts

• Published in: Journal of luminescence Vol. 282; p. 121249
• Main Authors: Chowdhury, Subhajit Roy, Santra, Suman, Ghosh, Koushik, Chakrabarty, Sudipta, Mandal, Jyoti, Giri, Pravat Kumar, Hossain, Syed Minhaz
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2025
• ISSN: 0022-2313
• DOI: 10.1016/j.jlumin.2025.121249

This work investigates the electroluminescent properties of Schottky junction LEDs based on nanostructured silicon. Despite the challenges with low efficiency, silicon-based light sources are gaining attention due to their compatibility with optoelectronic integrated circuits. This study explores the effect of metal contacts (Silver, Gold, Copper) that play an influencing role in the electroluminescence properties of these devices, by the key parameters such as the optical transparency, work function and solid solubility of the metals in the silicon oxide matrix. These factors affect injection and extraction efficiencies, as well as the emission spectrum, which is characterized by bias-dependent multiple peaks owing to the radiative transitions between the quantum-confined Bloch states and oxide-related interface trap states within the band gap of the nanostructured silicon. Among the metal contacts studied, Silver provides the highest external quantum efficiency integrated over a broad emission spectrum, demonstrating its potential as a source in photonic devices. [Display omitted] •Comparison of Au, Ag and Cu as semi-transparent contact for Nano-Si Schottky LED.•Metals' Solid solubility in SiOx matrix and transparency determine the performance.•Ag shows brightest visible EL with peaks distributed throughout the visible region.•Intensity and position of the observed peaks are voltage-tuneable.