Mesoscale trumps nanoscale: metallic mesoscale contact morphology for improved light trapping, optical absorption and grid conductance in silicon solar cells
Abstract
Here, we report on a computational study exploring the design of mesoscale metallic front contacts for solar cells. We investigated silver contact structures with circle, triangle and square cross-sections for various length scales and surface coverages. We found that for ‘nanoscale’ contacts with widths between 10 nm and 1000 nm, resonant coupling actually impairs light absorption in the semiconductor. Conversely, for ‘mesoscale’ contact widths > 1000 nm, the light interaction is determined by the geometric shadowing. We find that mesoscale silver contacts with triangular cross-section outperform other nanostructure morphologies in reducing shadow losses and yield contact transparency of >99% percent with sheet resistance <0.2 Ω/sq. Surprisingly, very densely spaced mesoscale silver triangular cross-section contacts can enhance the absorption of thin silicon/silver structures by up to 15% at a front contact coverage of 83%, due to light trapping by the front contact. Such structures can also maintain up to 100% absorption within the silicon, at a front contact coverage of 50%, relative to the same structure without metal.
- Authors:
- Publication Date:
- Research Org.:
- The Leland Stanford Junior Univ., Palo Alto, CA (United States)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- OSTI Identifier:
- 1423923
- Alternate Identifier(s):
- OSTI ID: 1503310
- Grant/Contract Number:
- EE0004946; EEC-1041895
- Resource Type:
- Published Article
- Journal Name:
- Optics Express
- Additional Journal Information:
- Journal Name: Optics Express Journal Volume: 26 Journal Issue: 6; Journal ID: ISSN 1094-4087
- Publisher:
- Optical Society of America
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; Solar energy; Micro-optics; Nanophotonics and photonic crystals
Citation Formats
Saive, Rebecca, and Atwater, Harry A. Mesoscale trumps nanoscale: metallic mesoscale contact morphology for improved light trapping, optical absorption and grid conductance in silicon solar cells. United States: N. p., 2018.
Web. doi:10.1364/OE.26.00A275.
Saive, Rebecca, & Atwater, Harry A. Mesoscale trumps nanoscale: metallic mesoscale contact morphology for improved light trapping, optical absorption and grid conductance in silicon solar cells. United States. https://doi.org/10.1364/OE.26.00A275
Saive, Rebecca, and Atwater, Harry A. Tue .
"Mesoscale trumps nanoscale: metallic mesoscale contact morphology for improved light trapping, optical absorption and grid conductance in silicon solar cells". United States. https://doi.org/10.1364/OE.26.00A275.
@article{osti_1423923,
title = {Mesoscale trumps nanoscale: metallic mesoscale contact morphology for improved light trapping, optical absorption and grid conductance in silicon solar cells},
author = {Saive, Rebecca and Atwater, Harry A.},
abstractNote = {Here, we report on a computational study exploring the design of mesoscale metallic front contacts for solar cells. We investigated silver contact structures with circle, triangle and square cross-sections for various length scales and surface coverages. We found that for ‘nanoscale’ contacts with widths between 10 nm and 1000 nm, resonant coupling actually impairs light absorption in the semiconductor. Conversely, for ‘mesoscale’ contact widths > 1000 nm, the light interaction is determined by the geometric shadowing. We find that mesoscale silver contacts with triangular cross-section outperform other nanostructure morphologies in reducing shadow losses and yield contact transparency of >99% percent with sheet resistance <0.2 Ω/sq. Surprisingly, very densely spaced mesoscale silver triangular cross-section contacts can enhance the absorption of thin silicon/silver structures by up to 15% at a front contact coverage of 83%, due to light trapping by the front contact. Such structures can also maintain up to 100% absorption within the silicon, at a front contact coverage of 50%, relative to the same structure without metal.},
doi = {10.1364/OE.26.00A275},
journal = {Optics Express},
number = 6,
volume = 26,
place = {United States},
year = {2018},
month = {3}
}
https://doi.org/10.1364/OE.26.00A275
Web of Science
Figures / Tables:

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Works referencing / citing this record:
Light trapping structures and plasmons synergistically enhance the photovoltaic performance of full-spectrum solar cells
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Figures / Tables found in this record: