Loughborough University
Browse

Optical optimization of high resistance transparent layers in thin film cadmium telluride solar cells

Download (583.12 kB)
journal contribution
posted on 2016-12-19, 14:54 authored by Gerald Womack, Piotr Kaminski, Michael WallsMichael Walls
Thin film photovoltaic devices are multilayer opto-electrical structures in which light interference occurs. Light reflection at the interfaces and absorption within the window layers reduces transmission and, ultimately, the conversion efficiency of photovoltaic devices. Optical reflection losses can be reduced by adjusting the layer thicknesses to achieve destructive interference within the structure of the cell. The light transmission to the CdTe absorber of a CdS/CdTe cell on a fluorine doped tin oxide transparent conductor has been modeled using the transfer matrix method. The interference effect in the CdS layer and high resistance transparent buffer layers (SnO2 and ZnO) has been investigated. The modeling shows that due to relatively high absorption within the SnO2 layer, there are modest benefits to engineering anti-reflection interference in the stack. However, a ZnO buffer layer has limited absorption and interference can be exploited to provide useful anti-reflection effects. Optical modeling and optimization shows that for a 50 nm CdS layer, a maximum transmission of 78.5% is possible using ZnO as a buffer layer at 58 nm thickness, and 78.0% for a SnO2 buffer layer at a thickness of 48 nm.

Funding

The authors are grateful to UKERC for funding this work through the EPSRC Supergen SuperSolar Hub, grant number: EP/J017361/1. One of the authors (GW) is grateful to Loughborough University Graduate School and NSIRC Ltd for supporting a CASE studentship.

History

School

  • Mechanical, Electrical and Manufacturing Engineering

Research Unit

  • Centre for Renewable Energy Systems Technology (CREST)

Published in

Vacuum

Citation

WOMACK, G., KAMINSKI, P.M. and WALLS, J.M., 2016. Optical optimization of high resistance transparent layers in thin film cadmium telluride solar cells. Vacuum, 139, pp. 196–201.

Publisher

© Elsevier

Version

  • AM (Accepted Manuscript)

Publisher statement

This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/

Acceptance date

2016-11-25

Publication date

2016

Notes

This paper was accepted for publication in the journal Vacuum and the definitive published version is available at http://dx.doi.org/10.1016/j.vacuum.2016.11.031.

ISSN

0042-207X

Language

  • en

Usage metrics

    Loughborough Publications

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC