Investigation of optical absorption in thin-film Si/Ge solar cells

Fariborz Jahanshah, M. Khizar, D. Modisette, Ron Manginell, Nowshad Amin, Kamaruzzaman Sopian, Saleem H. Zaidi

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Citations (Scopus)

Abstract

Thin-film, high efficiency crystalline Si solar cells promise significant cost savings in contrast with conventional substrate solar cells. These savings are achieved through reduced Si usage assuming highly (∼ 20-30%) efficient thin film Si solar cells can be manufactured. A necessary condition for high efficiency solar cells in thin-film configurations is complete optical absorption of sunlight. However, due to its indirect bandgap, Si has inherently weak absorption in near IR region so thicker films are required to accommodate longer path lengths. Even incorporation of scattering mechanisms (geometrical, diffractive, and physical) is not enough to achieve complete absorption in Si thin-films . We propose thin-film crystalline Si/Ge solar cell configuration in which the top surface comprises of thin Si film and the bottom surface of thin Ge film. This heterojunction solar cell combines the best attributes of both materials with strong Si absorption in the visible followed by absorption in Ge through most of the near IR region. The absorption spectrum ranges from 300 nm to 1600 nm in this solar cell with only two thin film layers. This approach has not been investigated extensively in past due to technical challenges associated with growth of high-quality Ge layers on Si. We have demonstrated growth of very high quality Si xGe 1-x and Ge films on nanostructured Si substrates, thus, identifying a promising pathway in addressing the fundamental problem of pseudomorphic growth of Ge on Si, a necessary condition for high efficiency heterojunction Si/Ge thin-film solar cells. Preliminary optical measurements on Si/Ge films exhibit strong absorption dependence on growth quality.

Original languageEnglish
Title of host publicationConference Record of the IEEE Photovoltaic Specialists Conference
Pages608-611
Number of pages4
DOIs
Publication statusPublished - 2009
Event2009 34th IEEE Photovoltaic Specialists Conference, PVSC 2009 - Philadelphia, PA
Duration: 7 Jun 200912 Jun 2009

Other

Other2009 34th IEEE Photovoltaic Specialists Conference, PVSC 2009
CityPhiladelphia, PA
Period7/6/0912/6/09

Fingerprint

Light absorption
Solar cells
Thin films
Heterojunctions
Crystalline materials
Substrates
Thick films
Absorption spectra
Energy gap
Scattering
Costs

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Control and Systems Engineering
  • Industrial and Manufacturing Engineering

Cite this

Jahanshah, F., Khizar, M., Modisette, D., Manginell, R., Amin, N., Sopian, K., & Zaidi, S. H. (2009). Investigation of optical absorption in thin-film Si/Ge solar cells. In Conference Record of the IEEE Photovoltaic Specialists Conference (pp. 608-611). [5411608] https://doi.org/10.1109/PVSC.2009.5411608

Investigation of optical absorption in thin-film Si/Ge solar cells. / Jahanshah, Fariborz; Khizar, M.; Modisette, D.; Manginell, Ron; Amin, Nowshad; Sopian, Kamaruzzaman; Zaidi, Saleem H.

Conference Record of the IEEE Photovoltaic Specialists Conference. 2009. p. 608-611 5411608.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Jahanshah, F, Khizar, M, Modisette, D, Manginell, R, Amin, N, Sopian, K & Zaidi, SH 2009, Investigation of optical absorption in thin-film Si/Ge solar cells. in Conference Record of the IEEE Photovoltaic Specialists Conference., 5411608, pp. 608-611, 2009 34th IEEE Photovoltaic Specialists Conference, PVSC 2009, Philadelphia, PA, 7/6/09. https://doi.org/10.1109/PVSC.2009.5411608
Jahanshah F, Khizar M, Modisette D, Manginell R, Amin N, Sopian K et al. Investigation of optical absorption in thin-film Si/Ge solar cells. In Conference Record of the IEEE Photovoltaic Specialists Conference. 2009. p. 608-611. 5411608 https://doi.org/10.1109/PVSC.2009.5411608
Jahanshah, Fariborz ; Khizar, M. ; Modisette, D. ; Manginell, Ron ; Amin, Nowshad ; Sopian, Kamaruzzaman ; Zaidi, Saleem H. / Investigation of optical absorption in thin-film Si/Ge solar cells. Conference Record of the IEEE Photovoltaic Specialists Conference. 2009. pp. 608-611
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