Optimization Strategy Aided by an Interplay Between Plasmonic Material and Nanoarray Geometry for Light Trapping Application in Thin-Film Photovoltaics

• Published in: Plasmonics (Norwell, Mass.) Mass.), 2016-12, Vol.11 (6), p.1467-1473
• Main Authors: Venkataramanababu, Sruthi, Shah, Manav, Vasudevan, Harikrishnan, Ramaswamy, Kannan
• Format: Article
• Language: English
• Subjects: Biochemistry; Biological and Medical Physics; Biophysics; Biotechnology; Chemistry; Chemistry and Materials Science; Nanospheres; Nanotechnology; Optical trapping; Photoelectric emission; Photovoltaic cells; Plasmonics; Thick films; Thin films
• ISSN: 1557-1955; 1557-1963
• DOI: 10.1007/s11468-016-0198-1

In this article, we have developed an optimization strategy taking into consideration the interplay between the choice of plasmonic material and geometrical parameters that lead to enhanced photocurrent density. We have demonstrated this by computing the optical absorption, using finite difference time domain technique, due to front-end placed aluminum and silver nanosphere arrays on 1- μm-thick film of silicon. Results from this optimization procedure indicate that over a broad wavelength range (∼600 nm onwards), absorption enhancement is primarily due to waveguiding effects and is independent of the plasmonic material. However, the significance of the plasmonic material becomes noticeable at lower wavelengths. The optimization yielded an inter-particle distance of 325 nm and nanosphere radius of 75 nm that corresponds to maximum photocurrent density for both aluminum and silver. Furthermore, it was noticed that the presence of a native oxide layer on aluminum does not deteriorate the enhancement significantly. In fact, the photocurrent density enhancement due to partially oxidized aluminum nanospheres is found to be better than using silver nanospheres.