Fabrication of a high sensitivity and fast response self-powered photosensor based on a core-shell silicon nanowire homojunction. (April 2018)

• Record Type: Journal Article
• Authors: Abdul-Hameed, Assel A.; Mahdi, M.A.; Ali, Basil; Selman, Abbas M.; Al-Taay, H.F.; Jennings, P.; Lee, Wen-Jen
• Is Part Of: Superlattices and microstructures. Volume 116(2018)
• Page Start: 27
• Page End: 35
• Publication Date: 2018-04
• Subjects: SiNWs -- Core-shell -- Photosensor -- Self-powered -- Homojunction; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2018.02.003
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: Core-shell self-powered SiNWs homojunction photosensors have been fabricated. SiNWs are prepared by a metal assisted chemical etching method using different HF/H2 O2 ratios and etching times. The length of the p-SiNWs increased as the H2 O2 concentration and etching time increased. All the grown SiNWs show very low (∼0.7%) optical reflectance for the wavelength range of 200–1100 nm. Photoluminescence spectra of all prepared SiNWs show sharp and broad emission bands located in the red region of the light spectrum. Core-shell homojunction photosensors were fabricated by spin coating P2 O2 onto the surface of the prepared p-SiNWs and annealed at 900 °C for 1 h. The fabricated devices exhibited photovoltaic behavior and high photosensitivity with fast response speed to the visible light. However, the sample that was fabricated using HF/H2 O2 ratio of 1:1 showed the highest photosensitivity value of 3578% while the photosensor prepared using 2:1 ratio of HF/H2 O2 gave the faster rise and decay time. Highlights: Core-shell Silicon nanowires are prepared. Core-shell homojunction photosensors were fabricated. Devices exhibited photovoltaic behaviour. Fast response speed to the visible light is obtained.