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: 3.29). 05/2011; 36(9):1713-5. DOI: 10.1364/OL.36.001713
Source: PubMed


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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    • "We therefore examine the absorption spectra of SNHs under two configurations, i.e., 1) large holes (d/a = 1) and 2) small holes (d/a = 0.5), as depicted in Figure 2b where the planar case (thickness = 2.33 μm) is also attached for comparison. It is observed that the absorption resonances exhibit obvious red shifts as d/a reduces [14]. This implies that SNHs with large holes show higher (weaker) light absorption in the short-wavelength (long-wavelength) region, while SNHs with smaller holes behave in a contrary way. "
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