Broadband antireflection and absorption enhancement of ultrathin silicon solar microcells enabled with density-graded surface nanostructures

Journal Article · Mon Jun 02 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4881260· OSTI ID:22300109

Chan, Lesley; Kang, Dongseok; Lee, Sung-Min; Li, Weigu; Hunter, Hajirah ^[1]; Yoon, Jongseung ^[1]

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1. Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089 (United States)

Density-graded surface nanostructures are implemented on ultrathin silicon solar microcells by silver-nanoparticle-catalyzed wet chemical etching to enable near-zero surface reflection over a broad wavelength range of incident solar spectrum as well as non-zeroth order diffraction and light trapping for longer wavelength photons, thereby achieving augmented photon absorption for ultrathin silicon microcells in a simple, cost-effective manner. The increase of absorbed photon flux through the “black silicon (b-Si)” surface translates directly into the corresponding enhancement of photovoltaic performance, where 5.7-μm b-Si microcells with the rational design of device configuration exhibit improved energy conversion efficiency by 148% and 50% with and without a diffuse backside reflector, respectively, compared to devices from the bare silicon without b-Si implementation. Systematic studies on nanostructured morphology, optical and electrical properties of b-Si microcells, together with semi-empirical numerical modeling of photon absorption, provide key aspects of underlying materials science and physics.

• OSTI ID: 22300109
• Journal Information: Applied Physics Letters, Vol. 104, Issue 22; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
DENSITY
DIFFRACTION
EFFICIENCY
ELECTRICAL PROPERTIES
ENERGY CONVERSION
NANOSTRUCTURES
OPTICAL PROPERTIES
PHOTONS
PHOTOVOLTAIC EFFECT
REFLECTION
SILICON
SILICON SOLAR CELLS
SILVER
SPECTRA
SURFACES
THIN FILMS
TRAPPING
WAVELENGTHS