Toward the Lambertian Limit of Light Trapping in Thin Nanostructured Silicon Solar Cells

Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Nano Letters (Impact Factor: 12.94). 10/2010; 10(11):4692-6. DOI: 10.1021/nl1029804
Source: PubMed

ABSTRACT We examine light trapping in thin silicon nanostructures for solar cell applications. Using group theory, we design surface nanostructures with an absorptance exceeding the Lambertian limit over a broad band at normal incidence. Further, we demonstrate that the absorptance of nanorod arrays closely follows the Lambertian limit for isotropic incident radiation. These effects correspond to a reduction in silicon mass by 2 orders of magnitude, pointing to the promising future of thin crystalline silicon solar cells.

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