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Title: Flexible micromorph tandem a-Si/{mu}c-Si solar cells

Abstract

The deposition of a stack of amorphous (a-Si:H) and microcrystalline ({mu}c-Si:H) tandem thin film silicon solar cells (micromorph) requires at least twice the time used for a single junction a-Si:H cell. However, micromorph devices have a higher potential efficiency, thanks to the broader absorption spectrum of {mu}c-Si:H material. High efficiencies can only be achieved by mitigating the nanocracks in the {mu}c-Si:H cell and the light-induced degradation of the a-Si:H cell. As a result, {mu}c-Si:H cell has to grow on a smooth substrate with large periodicity (>1 {mu}m) and the a-Si:H cell on sharp pyramids with smaller feature size ({approx}350 nm) to strongly scatter the light in the weak absorption spectra of a-Si:H material. The asymmetric intermediate reflector introduced in this work uncouples the growth and light scattering issues of the tandem micromorph solar cells. The stabilized efficiency of the tandem n-i-p/n-i-p micromorph is increased by a relative 15% compared to a cell without AIR and 32% in relative compared to an a-Si:H single junction solar cells. The overall process (T<200 deg. C) is kept compatible with low cost plastic substrates. The best stabilized efficiency of a cell deposited on polyethylene-naphthalate plastic substrate is 9.8% after 1000 h of light soakingmore » at V{sub oc}, 1 sun, and 50 deg. C.« less

Authors:
; ; ;  [1]
  1. Photovoltaics and Thin Film Electronics Laboratory, Institute of Microengineering (IMT), Ecole Polytechnique Federale de Lausanne (EPFL), Rue A.-L. Breguet 2, CH-2000 Neuchatel (Switzerland)
Publication Date:
OSTI Identifier:
21476088
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 107; Journal Issue: 1; Other Information: DOI: 10.1063/1.3275860; (c) 2010 American Institute of Physics; Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION SPECTRA; AMORPHOUS STATE; CHEMICAL VAPOR DEPOSITION; CRYSTAL GROWTH; CRYSTALS; EFFICIENCY; HYDROGEN; LIGHT SCATTERING; POLYETHYLENES; SEMICONDUCTOR JUNCTIONS; SEMICONDUCTOR MATERIALS; SILICON SOLAR CELLS; SUBSTRATES; THIN FILMS; CHEMICAL COATING; DEPOSITION; DIRECT ENERGY CONVERTERS; ELEMENTS; EQUIPMENT; FILMS; MATERIALS; NONMETALS; ORGANIC COMPOUNDS; ORGANIC POLYMERS; PHOTOELECTRIC CELLS; PHOTOVOLTAIC CELLS; POLYMERS; POLYOLEFINS; SCATTERING; SOLAR CELLS; SOLAR EQUIPMENT; SPECTRA; SURFACE COATING

Citation Formats

Soederstroem, T, Haug, F -J, Terrazzoni-Daudrix, V, and Ballif, C. Flexible micromorph tandem a-Si/{mu}c-Si solar cells. United States: N. p., 2010. Web. doi:10.1063/1.3275860.
Soederstroem, T, Haug, F -J, Terrazzoni-Daudrix, V, & Ballif, C. Flexible micromorph tandem a-Si/{mu}c-Si solar cells. United States. https://doi.org/10.1063/1.3275860
Soederstroem, T, Haug, F -J, Terrazzoni-Daudrix, V, and Ballif, C. 2010. "Flexible micromorph tandem a-Si/{mu}c-Si solar cells". United States. https://doi.org/10.1063/1.3275860.
@article{osti_21476088,
title = {Flexible micromorph tandem a-Si/{mu}c-Si solar cells},
author = {Soederstroem, T and Haug, F -J and Terrazzoni-Daudrix, V and Ballif, C},
abstractNote = {The deposition of a stack of amorphous (a-Si:H) and microcrystalline ({mu}c-Si:H) tandem thin film silicon solar cells (micromorph) requires at least twice the time used for a single junction a-Si:H cell. However, micromorph devices have a higher potential efficiency, thanks to the broader absorption spectrum of {mu}c-Si:H material. High efficiencies can only be achieved by mitigating the nanocracks in the {mu}c-Si:H cell and the light-induced degradation of the a-Si:H cell. As a result, {mu}c-Si:H cell has to grow on a smooth substrate with large periodicity (>1 {mu}m) and the a-Si:H cell on sharp pyramids with smaller feature size ({approx}350 nm) to strongly scatter the light in the weak absorption spectra of a-Si:H material. The asymmetric intermediate reflector introduced in this work uncouples the growth and light scattering issues of the tandem micromorph solar cells. The stabilized efficiency of the tandem n-i-p/n-i-p micromorph is increased by a relative 15% compared to a cell without AIR and 32% in relative compared to an a-Si:H single junction solar cells. The overall process (T<200 deg. C) is kept compatible with low cost plastic substrates. The best stabilized efficiency of a cell deposited on polyethylene-naphthalate plastic substrate is 9.8% after 1000 h of light soaking at V{sub oc}, 1 sun, and 50 deg. C.},
doi = {10.1063/1.3275860},
url = {https://www.osti.gov/biblio/21476088}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 1,
volume = 107,
place = {United States},
year = {Fri Jan 15 00:00:00 EST 2010},
month = {Fri Jan 15 00:00:00 EST 2010}
}