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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 20, Iss. 4 — Feb. 13, 2012
  • pp: 3479–3489

Use of two-dimensional nanorod arrays with slanted ITO film to enhance optical absorption for photovoltaic applications

Yung-Chi Yao, Meng-Tsan Tsai, Hsu-Cheng Hsu, Li-Wei She, Chun-Mao Cheng, Yi-Ching Chen, Chien-Jang Wu, and Ya-Ju Lee  »View Author Affiliations

Optics Express, Vol. 20, Issue 4, pp. 3479-3489 (2012)

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Two-dimensional (2D) Si-nanorod arrays offer a promising architecture that has been widely recognized as attractive devices for photovoltaic applications. To further reduce the Fresnel reflection that occurs at the interface between the air and the 2D Si-nanorod array because of the large difference in their effective refractive indices, we propose and adopt a slanted ITO film as an intermediate layer by using oblique-angle sputtering deposition. The nearly continuous surface of the slanted ITO film is lossless and has high electrical conductivity; therefore, it could serve as an electrode layer for solar cells. As a result, the combination of the above-mentioned nanostructures exhibits high optical absorption over a broad range of wavelengths and incident angles, along with a calculated short-circuit current density of JSC = 32.81 mA/cm2 and a power generation efficiency of η = 22.70%, which corresponds to an improvement of approximately 42% over that of its bare single-crystalline Si counterpart.

© 2012 OSA

OCIS Codes
(040.5350) Detectors : Photovoltaic
(310.1210) Thin films : Antireflection coatings
(220.4241) Optical design and fabrication : Nanostructure fabrication
(310.7005) Thin films : Transparent conductive coatings

ToC Category:

Original Manuscript: November 15, 2011
Revised Manuscript: January 13, 2012
Manuscript Accepted: January 20, 2012
Published: January 30, 2012

Yung-Chi Yao, Meng-Tsan Tsai, Hsu-Cheng Hsu, Li-Wei She, Chun-Mao Cheng, Yi-Ching Chen, Chien-Jang Wu, and Ya-Ju Lee, "Use of two-dimensional nanorod arrays with slanted ITO film to enhance optical absorption for photovoltaic applications," Opt. Express 20, 3479-3489 (2012)

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