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Title: Tabula Rasa for n -Cz silicon-based photovoltaics

Abstract

Abstract High‐temperature annealing, known as Tabula Rasa (TR), proves to be an effective method for dissolving oxygen precipitate nuclei in n‐ Cz silicon and makes this material resistant to temperature‐induced and process‐induced lifetime degradation. Tabula Rasa is especially effective in n ‐Cz wafers with oxygen concentration >15 ppma. Vacancies, self‐interstitials, and their aggregates result from TR as a metastable side effect. Temperature‐dependent lifetime spectroscopy reveals that these metastable defects have shallow energy levels ~0.12 eV. Their concentrations strongly depend on the ambient gases during TR because of an offset of the thermal equilibrium between vacancies and self‐interstitials. However, these metastable defects anneal out at typical cell processing temperatures ≥850°C and have little effect on the bulk lifetime of the processed cell structures. Without dissolving built‐in oxygen precipitate nuclei, high‐temperature solar cell processing severely degrades the minority carrier lifetimes to below 0.1 millisecond, while TR‐treated n ‐Cz wafers after the cell processing steps exhibit carrier lifetimes above 2.2 milliseconds.

Authors:
ORCiD logo [1];  [2];  [2];  [2];  [1];  [1];  [3];  [2];  [1]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  3. Woongjin Energy Co. Ltd., Daejoen (Korea, Republic of)
Publication Date:
Research Org.:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
OSTI Identifier:
1471291
Alternate Identifier(s):
OSTI ID: 1464649
Report Number(s):
NREL/JA-5900-71883
Journal ID: ISSN 1062-7995
Grant/Contract Number:  
AC36-08GO28308
Resource Type:
Accepted Manuscript
Journal Name:
Progress in Photovoltaics
Additional Journal Information:
Journal Volume: 27; Journal Issue: 2; Journal ID: ISSN 1062-7995
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; PV; solar; Tabula Rasa

Citation Formats

LaSalvia, Vincenzo, Youssef, Amanda, Jensen, Mallory A., Looney, Erin E., Nemeth, William, Page, Matthew, Nam, Wooseok, Buonassisi, Tonio, and Stradins, Paul. Tabula Rasa for n -Cz silicon-based photovoltaics. United States: N. p., 2018. Web. doi:10.1002/pip.3068.
LaSalvia, Vincenzo, Youssef, Amanda, Jensen, Mallory A., Looney, Erin E., Nemeth, William, Page, Matthew, Nam, Wooseok, Buonassisi, Tonio, & Stradins, Paul. Tabula Rasa for n -Cz silicon-based photovoltaics. United States. https://doi.org/10.1002/pip.3068
LaSalvia, Vincenzo, Youssef, Amanda, Jensen, Mallory A., Looney, Erin E., Nemeth, William, Page, Matthew, Nam, Wooseok, Buonassisi, Tonio, and Stradins, Paul. Tue . "Tabula Rasa for n -Cz silicon-based photovoltaics". United States. https://doi.org/10.1002/pip.3068. https://www.osti.gov/servlets/purl/1471291.
@article{osti_1471291,
title = {Tabula Rasa for n -Cz silicon-based photovoltaics},
author = {LaSalvia, Vincenzo and Youssef, Amanda and Jensen, Mallory A. and Looney, Erin E. and Nemeth, William and Page, Matthew and Nam, Wooseok and Buonassisi, Tonio and Stradins, Paul},
abstractNote = {Abstract High‐temperature annealing, known as Tabula Rasa (TR), proves to be an effective method for dissolving oxygen precipitate nuclei in n‐ Cz silicon and makes this material resistant to temperature‐induced and process‐induced lifetime degradation. Tabula Rasa is especially effective in n ‐Cz wafers with oxygen concentration >15 ppma. Vacancies, self‐interstitials, and their aggregates result from TR as a metastable side effect. Temperature‐dependent lifetime spectroscopy reveals that these metastable defects have shallow energy levels ~0.12 eV. Their concentrations strongly depend on the ambient gases during TR because of an offset of the thermal equilibrium between vacancies and self‐interstitials. However, these metastable defects anneal out at typical cell processing temperatures ≥850°C and have little effect on the bulk lifetime of the processed cell structures. Without dissolving built‐in oxygen precipitate nuclei, high‐temperature solar cell processing severely degrades the minority carrier lifetimes to below 0.1 millisecond, while TR‐treated n ‐Cz wafers after the cell processing steps exhibit carrier lifetimes above 2.2 milliseconds.},
doi = {10.1002/pip.3068},
journal = {Progress in Photovoltaics},
number = 2,
volume = 27,
place = {United States},
year = {2018},
month = {8}
}

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Works referencing / citing this record:

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