High-Performance TiO2-Based Electron-Selective Contacts for Crystalline Silicon Solar Cells

Xinbo Yang; Qunyu Bi; Haider Ali; Kristopher Davis; Winston V. Schoenfeld; Klaus Weber

doi:10.1002/adma.201600926

High-Performance TiO₂-Based Electron-Selective Contacts for Crystalline Silicon Solar Cells

Xinbo Yang^*, Qunyu Bi, Haider Ali, Kristopher Davis, Winston V. Schoenfeld, Klaus Weber

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

315 Scopus citations

Abstract

A high-quality, low-cost TiO₂ -based electron-selective contact for silicon solar cells was developed. Thin TiO₂ films were deposited by ALD with the titanium chloride titanium precursor and H₂O oxidant at a low temperature of 75°C, and N₂ was used as the purge gas. To investigate the surface passivation quality of thin TiO₂ on silicon surfaces, symmetrical test structures were fabricated on (100)-oriented n-type and p-type silicon wafers to allow injection-dependent lifetime measurement utilizing the quasi-steady state Photoconductance (QSSPC) technique. The wafers were chemical-polished and RCA cleaned followed by a short dip in diluted HF before TiO₂ film deposition. TiO₂ film thicknesses were determined from ellipsometry measurement by fitting polarized reflectance data of single side polished silicon wafers. The implementation of the TiO₂ -based contacts reduces the surface recombination and contact resistivity at the silicon and metal interface simultaneously, resulting in a higher V oc and FF for silicon solar cells. The champion efficiency of 21.6% has been achieved on the n-type silicon solar cell featuring a full-area TiO₂ -based contact.

Original language	English (US)
Pages (from-to)	5891-5897
Number of pages	7
Journal	Advanced Materials
Volume	28
Issue number	28
DOIs	https://doi.org/10.1002/adma.201600926
State	Published - Jul 2016
Externally published	Yes

Bibliographical note

Funding Information:
The authors acknowledge financial support from the Australian Renewable Energy Agency (ARENA) under the Postdoctoral Fellowship and the Australian-US institute for Advanced Photovoltaics (AUSIAPV) under the collaboration grant. The authors would like to thank James Bullock (ANU) for the helpful discussion and suggestions. The authors would also like to acknowledge support for this work by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, in the Solar Energy Technologies Program, under Award No. DE-EE0004947. The Materials Characterization Facility (MCF) at University of Central Florida (UCF) is acknowledged for usage of its facilities.

Keywords

carrier-selective contacts
heterojunctions
solar cells
titanium dioxide

ASJC Scopus subject areas

General Materials Science
Mechanics of Materials
Mechanical Engineering

Access to Document

10.1002/adma.201600926

Cite this

@article{8b70327d093c47cd8cdf47894c4ec684,

title = "High-Performance TiO2-Based Electron-Selective Contacts for Crystalline Silicon Solar Cells",

abstract = "A high-quality, low-cost TiO2 -based electron-selective contact for silicon solar cells was developed. Thin TiO2 films were deposited by ALD with the titanium chloride titanium precursor and H2O oxidant at a low temperature of 75°C, and N2 was used as the purge gas. To investigate the surface passivation quality of thin TiO2 on silicon surfaces, symmetrical test structures were fabricated on (100)-oriented n-type and p-type silicon wafers to allow injection-dependent lifetime measurement utilizing the quasi-steady state Photoconductance (QSSPC) technique. The wafers were chemical-polished and RCA cleaned followed by a short dip in diluted HF before TiO2 film deposition. TiO2 film thicknesses were determined from ellipsometry measurement by fitting polarized reflectance data of single side polished silicon wafers. The implementation of the TiO2 -based contacts reduces the surface recombination and contact resistivity at the silicon and metal interface simultaneously, resulting in a higher V oc and FF for silicon solar cells. The champion efficiency of 21.6% has been achieved on the n-type silicon solar cell featuring a full-area TiO2 -based contact.",

keywords = "carrier-selective contacts, heterojunctions, solar cells, titanium dioxide",

author = "Xinbo Yang and Qunyu Bi and Haider Ali and Kristopher Davis and Schoenfeld, {Winston V.} and Klaus Weber",

note = "Funding Information: The authors acknowledge financial support from the Australian Renewable Energy Agency (ARENA) under the Postdoctoral Fellowship and the Australian-US institute for Advanced Photovoltaics (AUSIAPV) under the collaboration grant. The authors would like to thank James Bullock (ANU) for the helpful discussion and suggestions. The authors would also like to acknowledge support for this work by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, in the Solar Energy Technologies Program, under Award No. DE-EE0004947. The Materials Characterization Facility (MCF) at University of Central Florida (UCF) is acknowledged for usage of its facilities.",

year = "2016",

month = jul,

doi = "10.1002/adma.201600926",

language = "English (US)",

volume = "28",

pages = "5891--5897",

journal = "Advanced Materials",

issn = "0935-9648",

publisher = "WILEY-V C H VERLAG GMBH",

number = "28",

}

TY - JOUR

T1 - High-Performance TiO2-Based Electron-Selective Contacts for Crystalline Silicon Solar Cells

AU - Yang, Xinbo

AU - Bi, Qunyu

AU - Ali, Haider

AU - Davis, Kristopher

AU - Schoenfeld, Winston V.

AU - Weber, Klaus

N1 - Funding Information: The authors acknowledge financial support from the Australian Renewable Energy Agency (ARENA) under the Postdoctoral Fellowship and the Australian-US institute for Advanced Photovoltaics (AUSIAPV) under the collaboration grant. The authors would like to thank James Bullock (ANU) for the helpful discussion and suggestions. The authors would also like to acknowledge support for this work by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, in the Solar Energy Technologies Program, under Award No. DE-EE0004947. The Materials Characterization Facility (MCF) at University of Central Florida (UCF) is acknowledged for usage of its facilities.

PY - 2016/7

Y1 - 2016/7

N2 - A high-quality, low-cost TiO2 -based electron-selective contact for silicon solar cells was developed. Thin TiO2 films were deposited by ALD with the titanium chloride titanium precursor and H2O oxidant at a low temperature of 75°C, and N2 was used as the purge gas. To investigate the surface passivation quality of thin TiO2 on silicon surfaces, symmetrical test structures were fabricated on (100)-oriented n-type and p-type silicon wafers to allow injection-dependent lifetime measurement utilizing the quasi-steady state Photoconductance (QSSPC) technique. The wafers were chemical-polished and RCA cleaned followed by a short dip in diluted HF before TiO2 film deposition. TiO2 film thicknesses were determined from ellipsometry measurement by fitting polarized reflectance data of single side polished silicon wafers. The implementation of the TiO2 -based contacts reduces the surface recombination and contact resistivity at the silicon and metal interface simultaneously, resulting in a higher V oc and FF for silicon solar cells. The champion efficiency of 21.6% has been achieved on the n-type silicon solar cell featuring a full-area TiO2 -based contact.

AB - A high-quality, low-cost TiO2 -based electron-selective contact for silicon solar cells was developed. Thin TiO2 films were deposited by ALD with the titanium chloride titanium precursor and H2O oxidant at a low temperature of 75°C, and N2 was used as the purge gas. To investigate the surface passivation quality of thin TiO2 on silicon surfaces, symmetrical test structures were fabricated on (100)-oriented n-type and p-type silicon wafers to allow injection-dependent lifetime measurement utilizing the quasi-steady state Photoconductance (QSSPC) technique. The wafers were chemical-polished and RCA cleaned followed by a short dip in diluted HF before TiO2 film deposition. TiO2 film thicknesses were determined from ellipsometry measurement by fitting polarized reflectance data of single side polished silicon wafers. The implementation of the TiO2 -based contacts reduces the surface recombination and contact resistivity at the silicon and metal interface simultaneously, resulting in a higher V oc and FF for silicon solar cells. The champion efficiency of 21.6% has been achieved on the n-type silicon solar cell featuring a full-area TiO2 -based contact.

KW - carrier-selective contacts

KW - heterojunctions

KW - solar cells

KW - titanium dioxide

UR - http://www.scopus.com/inward/record.url?scp=84979020966&partnerID=8YFLogxK

U2 - 10.1002/adma.201600926

DO - 10.1002/adma.201600926

M3 - Article

C2 - 27159874

AN - SCOPUS:84979020966

SN - 0935-9648

VL - 28

SP - 5891

EP - 5897

JO - Advanced Materials

JF - Advanced Materials

IS - 28

ER -