Silver Nanoparticles in Epoxy Resin Deposited on Silicon Substrates for Light Trapping

• Published in: Plasmonics (Norwell, Mass.) Vol. 11; no. 4; pp. 971 - 979
• Main Authors: Molina, Yehoshua Aguilar, Tapia, Víctor Rentería, Calva, Enrique Barrera
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.08.2016
• Subjects: Biochemistry; Biological and Medical Physics; Biophysics; Biotechnology; Chemistry; Chemistry and Materials Science; Nanotechnology; Epoxy resin; Antireflective coatings; Broadband plasmons; Optical properties; Silver nanoparticles
• ISSN: 1557-1955; 1557-1963
• DOI: 10.1007/s11468-015-0131-z

Metallic silver nanoparticles were prepared in epoxy resin using N , N -dimethylformamide (DMF) as reducing agent of silver ions at room temperature. They were characterized by UV–Vis spectroscopy, atomic force microscopy (AFM), transmission electronic microscopy (TEM), and high-resolution transmission electronic microscopy (HRTEM). The silver nanoparticles showed broadband absorption spectra attributed to high-order plasmonic resonances. The morphology of the metallic particles corresponds to elongated particles and their aggregates with a size above 30 nm. These silver nanoparticles were deposited by the spin-coating process on crystalline silicon at room temperature. Then, the antireflective properties of these samples were measured. According to the observed results, it is inferred that the films of coalesced silver nanoparticles decrease the reflectance of crystalline silicon better than particles separated by large distances. These results are discussed in terms of forward scattering of large metallic nanoparticles where higher order multipolar modes are dominant and the retardation effects are very important.