Beneficial effect of post-deposition treatment in high-efficiency Cu(In,Ga)Se2 solar cells through reduced potential fluctuations
Abstract
World-record power conversion efficiencies for Cu(In,Ga)Se2 (CIGS) solar cells have been achieved via a post-deposition treatment with alkaline metals, which increases the open-circuit voltage and fill factor. We explore the role of the potassium fluoride (KF) post-deposition treatment in CIGS by employing energy- and time-resolved photoluminescence spectroscopy and electrical characterization combined with numerical modeling. The bulk carrier lifetime is found to increase with post-deposition treatment from 255 ns to 388 ns, which is the longest charge carrier lifetime reported for CIGS, and within ~40% of the radiative limit. We find evidence that the post-deposition treatment causes a decrease in the electronic potential fluctuations. These potential fluctuations have previously been shown to reduce the open-circuit voltage and the device efficiency in CIGS. Additionally, numerical simulations based on the measured carrier lifetimes and mobilities show a diffusion length of ~10 um, which is ~4 times larger than the film thickness. Furthermore, carrier collection in the bulk is not a limiting factor for device efficiency. By considering differences in doping, bandgap, and potential fluctuations, we present a possible explanation for the voltage difference between KF-treated and untreated samples.
- Authors:
-
[1];
[1]
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- National Renewable Energy Lab. (NREL), Golden, CO (United States); Texas State Univ., San Marcos, TX (United States)
- 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:
- 1310173
- Alternate Identifier(s):
- OSTI ID: 1294677
- Report Number(s):
- NREL/JA-5J00-65144
Journal ID: ISSN 0021-8979; JAPIAU
- Grant/Contract Number:
- AC36-08GO28308
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Applied Physics
- Additional Journal Information:
- Journal Volume: 120; Journal Issue: 6; Journal ID: ISSN 0021-8979
- Publisher:
- American Institute of Physics (AIP)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 14 SOLAR ENERGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CIGS; PDT; KF; TRPL; potential fluctuations; numerical methods; converters; chemical elements; polycrystalline material; electrical characterization; transition metal chalcogenides; band gap; time-resolved photoluminescence spectroscopy; thin films; electrical properties and parameters
Citation Formats
Jensen, Soren A., Glynn, Stephen, Kanevce, Ana, Dippo, Pat, Li, Jian V., Levi, Dean H., and Kuciauskas, Darius. Beneficial effect of post-deposition treatment in high-efficiency Cu(In,Ga)Se2 solar cells through reduced potential fluctuations. United States: N. p., 2016.
Web. doi:10.1063/1.4960344.
Jensen, Soren A., Glynn, Stephen, Kanevce, Ana, Dippo, Pat, Li, Jian V., Levi, Dean H., & Kuciauskas, Darius. Beneficial effect of post-deposition treatment in high-efficiency Cu(In,Ga)Se2 solar cells through reduced potential fluctuations. United States. https://doi.org/10.1063/1.4960344
Jensen, Soren A., Glynn, Stephen, Kanevce, Ana, Dippo, Pat, Li, Jian V., Levi, Dean H., and Kuciauskas, Darius. Fri .
"Beneficial effect of post-deposition treatment in high-efficiency Cu(In,Ga)Se2 solar cells through reduced potential fluctuations". United States. https://doi.org/10.1063/1.4960344. https://www.osti.gov/servlets/purl/1310173.
@article{osti_1310173,
title = {Beneficial effect of post-deposition treatment in high-efficiency Cu(In,Ga)Se2 solar cells through reduced potential fluctuations},
author = {Jensen, Soren A. and Glynn, Stephen and Kanevce, Ana and Dippo, Pat and Li, Jian V. and Levi, Dean H. and Kuciauskas, Darius},
abstractNote = {World-record power conversion efficiencies for Cu(In,Ga)Se2 (CIGS) solar cells have been achieved via a post-deposition treatment with alkaline metals, which increases the open-circuit voltage and fill factor. We explore the role of the potassium fluoride (KF) post-deposition treatment in CIGS by employing energy- and time-resolved photoluminescence spectroscopy and electrical characterization combined with numerical modeling. The bulk carrier lifetime is found to increase with post-deposition treatment from 255 ns to 388 ns, which is the longest charge carrier lifetime reported for CIGS, and within ~40% of the radiative limit. We find evidence that the post-deposition treatment causes a decrease in the electronic potential fluctuations. These potential fluctuations have previously been shown to reduce the open-circuit voltage and the device efficiency in CIGS. Additionally, numerical simulations based on the measured carrier lifetimes and mobilities show a diffusion length of ~10 um, which is ~4 times larger than the film thickness. Furthermore, carrier collection in the bulk is not a limiting factor for device efficiency. By considering differences in doping, bandgap, and potential fluctuations, we present a possible explanation for the voltage difference between KF-treated and untreated samples.},
doi = {10.1063/1.4960344},
journal = {Journal of Applied Physics},
number = 6,
volume = 120,
place = {United States},
year = {Fri Aug 12 00:00:00 EDT 2016},
month = {Fri Aug 12 00:00:00 EDT 2016}
}
Free Publicly Available Full Text
Publisher's Version of Record
Other availability
Search WorldCat to find libraries that may hold this journal
Cited by: 68 works
Citation information provided by
Web of Science
Web of Science
Save to My Library
You must Sign In or Create an Account in order to save documents to your library.
Works referenced in this record:
Comparative study of the luminescence and intrinsic point defects in the kesterite CuZnSnS and chalcopyrite Cu(In,Ga)Se thin films used in photovoltaic applications
journal, October 2011
- Romero, Manuel J.; Du, Hui; Teeter, Glenn
- Physical Review B, Vol. 84, Issue 16, Article No. 165324
Band tailing and efficiency limitation in kesterite solar cells
journal, September 2013
- Gokmen, Tayfun; Gunawan, Oki; Todorov, Teodor K.
- Applied Physics Letters, Vol. 103, Issue 10
Characterization of CuIn(Ga)Se2 Thin Films
journal, July 1998
- Dirnstorfer, I.; Wagner, Mt.; Hofmann, D. M.
- physica status solidi (a), Vol. 168, Issue 1
Radiative transitions in highly doped and compensated chalcopyrites and kesterites: The case of
journal, December 2014
- Teixeira, J. P.; Sousa, R. A.; Sousa, M. G.
- Physical Review B, Vol. 90, Issue 23
What limits the efficiency of chalcopyrite solar cells?
journal, June 2011
- Siebentritt, Susanne
- Solar Energy Materials and Solar Cells, Vol. 95, Issue 6
Radiative efficiency limits of solar cells with lateral band-gap fluctuations
journal, May 2004
- Rau, U.; Werner, J. H.
- Applied Physics Letters, Vol. 84, Issue 19
Efficiency limitations of polycrystalline thin film solar cells: case of Cu(In,Ga)Se2
journal, June 2005
- Werner, Jürgen H.; Mattheis, Julian; Rau, Uwe
- Thin Solid Films, Vol. 480-481
Efficiency enhancement of Cu(In,Ga)Se2 solar cells due to post-deposition Na incorporation
journal, February 2004
- Rudmann, D.; da Cunha, A. F.; Kaelin, M.
- Applied Physics Letters, Vol. 84, Issue 7
Na incorporation into Cu(In,Ga)Se2 for high-efficiency flexible solar cells on polymer foils
journal, April 2005
- Rudmann, D.; Brémaud, D.; Zogg, H.
- Journal of Applied Physics, Vol. 97, Issue 8
Potassium-induced surface modification of Cu(In,Ga)Se2 thin films for high-efficiency solar cells
journal, November 2013
- Chirilă, Adrian; Reinhard, Patrick; Pianezzi, Fabian
- Nature Materials, Vol. 12, Issue 12
Unveiling the effects of post-deposition treatment with different alkaline elements on the electronic properties of CIGS thin film solar cells
journal, January 2014
- Pianezzi, Fabian; Reinhard, Patrick; Chirilă, Adrian
- Physical Chemistry Chemical Physics, Vol. 16, Issue 19
Compositional investigation of potassium doped Cu(In,Ga)Se 2 solar cells with efficiencies up to 20.8% : Compositional investigation of potassium doped Cu(In,Ga)Se
journal, February 2014
- Jackson, Philip; Hariskos, Dimitrios; Wuerz, Roland
- physica status solidi (RRL) - Rapid Research Letters, Vol. 8, Issue 3
Properties of Cu(In,Ga)Se 2 solar cells with new record efficiencies up to 21.7% : Properties of Cu(In,Ga)Se
journal, December 2014
- Jackson, Philip; Hariskos, Dimitrios; Wuerz, Roland
- physica status solidi (RRL) - Rapid Research Letters, Vol. 9, Issue 1
High‐efficiency CuIn x Ga 1− x Se 2 solar cells made from (In x ,Ga 1− x ) 2 Se 3 precursor films
journal, July 1994
- Gabor, Andrew M.; Tuttle, John R.; Albin, David S.
- Applied Physics Letters, Vol. 65, Issue 2
19·9%-efficient ZnO/CdS/CuInGaSe 2 solar cell with 81·2% fill factor
journal, May 2008
- Repins, Ingrid; Contreras, Miguel A.; Egaas, Brian
- Progress in Photovoltaics: Research and Applications, Vol. 16, Issue 3
Long lifetimes in high-efficiency Cu(In,Ga)Se2 solar cells
journal, July 2008
- Metzger, Wyatt K.; Repins, Ingrid L.; Contreras, Miguel A.
- Applied Physics Letters, Vol. 93, Issue 2
Recombination kinetics and stability in polycrystalline Cu(In,Ga)Se2 solar cells
journal, February 2009
- Metzger, W. K.; Repins, I. L.; Romero, M.
- Thin Solid Films, Vol. 517, Issue 7, p. 2360-2364
Fiber-fed time-resolved photoluminescence for reduced process feedback time on thin-film photovoltaics
journal, January 2015
- Repins, I. L.; Egaas, B.; Mansfield, L. M.
- Review of Scientific Instruments, Vol. 86, Issue 1
Thin-film solar cells: device measurements and analysis
journal, March 2004
- Hegedus, Steven S.; Shafarman, William N.
- Progress in Photovoltaics: Research and Applications, Vol. 12, Issue 23
Optical functions of chalcopyrite CuGaxIn1-xSe2 alloys
journal, May 2002
- Alonso, M. I.; Garriga, M.; Durante Rincón, C. A.
- Applied Physics A: Materials Science & Processing, Vol. 74, Issue 5, p. 659-664
Photoluminescence and electrical study of fluctuating potentials in Cu ZnSnS -based thin films
journal, July 2011
- Leitão, J. P.; Santos, N. M.; Fernandes, P. A.
- Physical Review B, Vol. 84, Issue 2
Reducing interface recombination for Cu(In,Ga)Se 2 by atomic layer deposited buffer layers
journal, July 2015
- Hultqvist, Adam; Li, Jian V.; Kuciauskas, Darius
- Applied Physics Letters, Vol. 107, Issue 3
Time-Resolved Microphotoluminescence Study of Cu(In,Ga)Se 2
journal, May 2011
- Sakurai, Takeaki; Taguchi, Keiki; Islam, Muhammad Monirul
- Japanese Journal of Applied Physics, Vol. 50, Issue 5S2
Effects of Ga addition to CuInSe2 on its electronic, structural, and defect properties
journal, June 1998
- Wei, Su-Huai; Zhang, S. B.; Zunger, Alex
- Applied Physics Letters, Vol. 72, Issue 24
Correlation Between Measured Minority-Carrier Lifetime and $\hbox{Cu}( \hbox{In}, \hbox{Ga})\hbox{Se}_{2}$ Device Performance
journal, November 2010
- Repins, Ingrid L.; Metzger, Wyatt K.; Perkins, Craig L.
- IEEE Transactions on Electron Devices, Vol. 57, Issue 11
Charge carrier dynamics and recombination in graded band gap CuIn 1−x Ga x Se 2 polycrystalline thin-film photovoltaic solar cell absorbers
journal, October 2013
- Kuciauskas, Darius; Li, Jian V.; Contreras, Miguel A.
- Journal of Applied Physics, Vol. 114, Issue 15
A recombination analysis of Cu(In,Ga)Se2 solar cells with low and high Ga compositions
journal, May 2014
- Li, Jian V.; Grover, Sachit; Contreras, Miguel A.
- Solar Energy Materials and Solar Cells, Vol. 124, p. 143-149
Theoretical study of time-resolved luminescence in semiconductors. III. Trap states in the band gap
journal, September 2015
- Maiberg, Matthias; Hölscher, Torsten; Zahedi-Azad, Setareh
- Journal of Applied Physics, Vol. 118, Issue 10
Investigation of long lifetimes in Cu(In,Ga)Se 2 by time-resolved photoluminescence
journal, September 2015
- Maiberg, Matthias; Hölscher, Torsten; Zahedi-Azad, Setareh
- Applied Physics Letters, Vol. 107, Issue 12
CdTe Solar Cells at the Threshold to 20% Efficiency
journal, October 2013
- Gloeckler, M.; Sankin, I.; Zhao, Z.
- IEEE Journal of Photovoltaics, Vol. 3, Issue 4
Radiative and interfacial recombination in CdTe heterostructures
journal, December 2014
- Swartz, C. H.; Edirisooriya, M.; LeBlanc, E. G.
- Applied Physics Letters, Vol. 105, Issue 22
Charge-carrier dynamics in polycrystalline thin-film CuIn1−xGaxSe2 photovoltaic devices after pulsed laser excitation: Interface and space-charge region analysis
journal, May 2015
- Kuciauskas, Darius; Li, Jian V.; Kanevce, Ana
- Journal of Applied Physics, Vol. 117, Issue 18
Technology advances needed for photovoltaics to achieve widespread grid price parity: Widespread grid price parity for photovoltaics
journal, April 2016
- Jones-Albertus, Rebecca; Feldman, David; Fu, Ran
- Progress in Photovoltaics: Research and Applications, Vol. 24, Issue 9
CdTe solar cells with open-circuit voltage breaking the 1 V barrier
journal, February 2016
- Burst, J. M.; Duenow, J. N.; Albin, D. S.
- Nature Energy, Vol. 1, Issue 3
Hybrid organic—inorganic perovskites: low-cost semiconductors with intriguing charge-transport properties
journal, January 2016
- Brenner, Thomas M.; Egger, David A.; Kronik, Leeor
- Nature Reviews Materials, Vol. 1, Issue 1
Physics of Semiconductor Devices
journal, October 1990
- Shur, Michael; Singh, Jasprit
- Physics Today, Vol. 43, Issue 10
Utility-scale solar PV performance enhancements through system-level modifications
journal, June 2020
- Glick, Andrew; Ali, Naseem; Bossuyt, Juliaan
- Scientific Reports, Vol. 10, Issue 1
Characterization of CuIn(Ga)Se2 Thin Films
journal, July 1998
- Wagner, Mt.; Hofmann, D. M.; Dirnstorfer, I.
- physica status solidi (a), Vol. 168, Issue 1
Physics of Semiconductor Devices
journal, June 1970
- Sze, S. M.; Mattis, Daniel C.
- Physics Today, Vol. 23, Issue 6
Works referencing / citing this record:
Heavy Alkali Treatment of Cu(In,Ga)Se 2 Solar Cells: Surface versus Bulk Effects
journal, January 2020
- Siebentritt, Susanne; Avancini, Enrico; Bär, Marcus
- Advanced Energy Materials, Vol. 10, Issue 8
Impact of heat-light soaking on potassium fluoride treated CIGS solar cells with CdS buffer layer
journal, November 2017
- Khatri, Ishwor; Shudo, Kosuke; Matsuura, Junpei
- Progress in Photovoltaics: Research and Applications, Vol. 26, Issue 3
Revealing the beneficial role of K in grain interiors, grain boundaries, and at the buffer interface for highly efficient CuInSe 2 solar cells
journal, June 2018
- Muzzillo, Christopher P.; Poplawsky, Jonathan D.; Tong, Ho Ming
- Progress in Photovoltaics: Research and Applications, Vol. 26, Issue 10
Impact of heat‐light soaking and heat‐bias soaking on NaF‐treated CIGS thin film solar cells
journal, April 2019
- Matsuura, Junpei; Khatri, Ishwor; Lin, Tzu‐Ying
- Progress in Photovoltaics: Research and Applications
Tunable Carrier Concentration of NaF-Treated CIGS Solar Cells Using Heat-Light Soaking and Subsequent Heating
journal, March 2018
- Matsuura, Junpei; Shudo, Kosuke; Khatri, Ishwor
- physica status solidi (RRL) - Rapid Research Letters, Vol. 12, Issue 5
The Effect of Electron Irradiation on Cesium Fluoride‐Free and Cesium Fluoride‐Treated Cu(In 1− x ,Ga x )Se 2 Solar Cells
journal, May 2019
- Khatri, Ishwor; Lin, Tzu-Ying; Nakada, Tokio
- physica status solidi (RRL) – Rapid Research Letters, Vol. 13, Issue 11
CIGS Thin Film Photovoltaic—Approaches and Challenges
book, November 2019
- Kessler, F.; Hariskos, D.; Spiering, S.
- High-Efficient Low-Cost Photovoltaics: Recent Developments, p. 175-218
Direct evidence for grain boundary passivation in Cu(In,Ga)Se2 solar cells through alkali-fluoride post-deposition treatments
journal, September 2019
- Nicoara, Nicoleta; Manaligod, Roby; Jackson, Philip
- Nature Communications, Vol. 10, Issue 1
Exceeding 20% efficiency with in situ group V doping in polycrystalline CdTe solar cells
journal, August 2019
- Metzger, W. K.; Grover, S.; Lu, D.
- Nature Energy, Vol. 4, Issue 10
Numerical simulations of two-photon absorption time-resolved photoluminescence to extract the bulk lifetime of semiconductors under varying surface recombination velocities
journal, March 2019
- Chin, Robert Lee; Pollard, Michael; Trupke, Thorsten
- Journal of Applied Physics, Vol. 125, Issue 10