Enhanced optical absorption in nanopatterned silicon thin films with a nano-cone-hole structure for photovoltaic applications.

School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798, Singapore.
Optics Letters (Impact Factor: 3.18). 05/2011; 36(9):1713-5. DOI: 10.1364/OL.36.001713
Source: PubMed

ABSTRACT In this paper, the optical properties of the silicon nano-cone-hole (NCH) structure array are studied. The ultimate efficiency of the optimized NCH array is enhanced by 23.11% compared to an optimized nanohole array of the same thickness. The absorptance enhancement of the NCH arrays is attributed to its lowered reflectance, more supported resonant modes, and enhanced mode interaction. The angular dependence of ultimate efficiency is also investigated.

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