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Title: Microscopic Distributions of Defect Luminescence From Subgrain Boundaries in Multicrystalline Silicon Wafers

Abstract

We investigate the microscopic distributions of sub-band-gap luminescence emission (the so-called D-lines D1/D2/D3/D4) and the band-to-band luminescence intensity, near recombination-active sub-grain boundaries in multicrystalline silicon wafers for solar cells. We find that the sub-band-gap luminescence from decorating defects/impurities (D1/D2) and from intrinsic dislocations (D3/D4) have distinctly different spatial distributions, and are asymmetric across the sub-grain boundaries. The presence of D1/D2 is correlated with a strong reduction in the band-to-band luminescence, indicating a higher recombination activity. In contrast, D3/D4 emissions are not strongly correlated with the band-to-band intensity. Based on spatially-resolved, synchrotron-based micro-X-ray fluorescence measurements of metal impurities, we confirm that high densities of metal impurities are present at locations with strong D1/D2 emission but low D3/D4 emission. Finally, we show that the observed asymmetry of the sub-band-gap luminescence across the sub-grain boundaries is due to their inclination below the wafer surface. Based on the luminescence asymmetries, the sub-grain boundaries are shown to share a common inclination locally, rather than be orientated randomly.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
Australian Research Council; National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1377895
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Journal of Photovoltaics; Journal Volume: 7; Journal Issue: 3
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; crystalline silicon; dislocations; grain boundaries; photoluminescence; photovoltaic cells

Citation Formats

Nguyen, Hieu T., Jensen, Mallory A., Li, Li, Samundsett, Christian, Sio, Hang C., Lai, Barry, Buonassisi, Tonio, and Macdonald, Daniel. Microscopic Distributions of Defect Luminescence From Subgrain Boundaries in Multicrystalline Silicon Wafers. United States: N. p., 2017. Web. doi:10.1109/JPHOTOV.2017.2684904.
Nguyen, Hieu T., Jensen, Mallory A., Li, Li, Samundsett, Christian, Sio, Hang C., Lai, Barry, Buonassisi, Tonio, & Macdonald, Daniel. Microscopic Distributions of Defect Luminescence From Subgrain Boundaries in Multicrystalline Silicon Wafers. United States. doi:10.1109/JPHOTOV.2017.2684904.
Nguyen, Hieu T., Jensen, Mallory A., Li, Li, Samundsett, Christian, Sio, Hang C., Lai, Barry, Buonassisi, Tonio, and Macdonald, Daniel. Mon . "Microscopic Distributions of Defect Luminescence From Subgrain Boundaries in Multicrystalline Silicon Wafers". United States. doi:10.1109/JPHOTOV.2017.2684904.
@article{osti_1377895,
title = {Microscopic Distributions of Defect Luminescence From Subgrain Boundaries in Multicrystalline Silicon Wafers},
author = {Nguyen, Hieu T. and Jensen, Mallory A. and Li, Li and Samundsett, Christian and Sio, Hang C. and Lai, Barry and Buonassisi, Tonio and Macdonald, Daniel},
abstractNote = {We investigate the microscopic distributions of sub-band-gap luminescence emission (the so-called D-lines D1/D2/D3/D4) and the band-to-band luminescence intensity, near recombination-active sub-grain boundaries in multicrystalline silicon wafers for solar cells. We find that the sub-band-gap luminescence from decorating defects/impurities (D1/D2) and from intrinsic dislocations (D3/D4) have distinctly different spatial distributions, and are asymmetric across the sub-grain boundaries. The presence of D1/D2 is correlated with a strong reduction in the band-to-band luminescence, indicating a higher recombination activity. In contrast, D3/D4 emissions are not strongly correlated with the band-to-band intensity. Based on spatially-resolved, synchrotron-based micro-X-ray fluorescence measurements of metal impurities, we confirm that high densities of metal impurities are present at locations with strong D1/D2 emission but low D3/D4 emission. Finally, we show that the observed asymmetry of the sub-band-gap luminescence across the sub-grain boundaries is due to their inclination below the wafer surface. Based on the luminescence asymmetries, the sub-grain boundaries are shown to share a common inclination locally, rather than be orientated randomly.},
doi = {10.1109/JPHOTOV.2017.2684904},
journal = {IEEE Journal of Photovoltaics},
number = 3,
volume = 7,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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