Horizon 2020 projects:

Backing the European PV Industry

September 27, 2018, Brussels, Belgium

Wolfram Witte

Zentrum für Sonnenenergie- und Wasserstoff-Forschung

Baden-Württemberg (ZSW), Germany

Sharc25: Super high efficiency Cu(In,Ga)Se2

thin-film solar cells approaching 25%

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1 ZSW, Stuttgart, Germany 2 Empa, Dübendorf, Switzerland 3 University of Luxembourg, Belvaux, Luxembourg 4 Groupe de Physique des Matériaux, Saint Etienne du Rouvray, France 5 University of Parma, Parma, Italy 6 Interuniversity Microelectronics Centrum (IMEC), Leuven, Belgium 7 Renewable Energy, HZB, Berlin, Germany 8 Energy Materials In-Situ Laboratory Berlin (EMIL), HZB, Berlin, Germany 9 INL - International Iberian Nanotechnology Laboratory, Braga, Portugal 10 Aalto University, Department of Applied Physics, Aalto, Finland 11 Flisom AG, Dübendorf, Switzerland 12 NICE Solar Energy GmbH, Schwäbisch Hall, Germany

W. Witte1, P. Jackson1, D. Hariskos1, F. Kessler1, M. Powalla1, S. Buecheler2,

R. Carron2, E. Avancini2, B. Bissig2, T. P. Weiss2, J. Löckinger2,

S. Siebentritt3, F. Werner3, M. H. Wolter3, P. Pareige4, S. Duguay4, E. Cadel4,

C. Castro4, A. Vilalta-Clemente4, R. Menozzi5, G. Sozzi5, S. Di Napoli5,

E. Bourgeois6, G. Degutis6, R. Gehlhaar6, M. Bär7,8, R. G. Wilks7,8, T. Kunze7,

E. Handick7, J. Bombsch7, S. Sadewasser9, N. Nicoara9, M. Puska10,

M. Malitckaya10, H.-P. Komsa10, V. Havu10, P. Reinhard11, B. Dimmler12,

R. Wächter12, and A. N. Tiwari2

Sharc25 facts and objective Sharc25 facts and objective

• GA number 641004

• Call: H2020-LCE-2014-1

• Topic: LCE-02

• Type of action: RIA

• Total Costs: € 6.15 Mio

• EU Grant Amount: € 4.56 Mio

• Start Date: 2015-05-01

• End Date: 2018-10-31

• TRL: 3-4 to 4-5

Thin-film PV: Cu(In,Ga)Se2 (CIGS)

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(CIGS)

→ Identification of loss mechanisms

Goal of Sharc25 project:

Push CIGS thin-film solar cell efficiency towards 25%

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2006 2008 2010 2012 2014 2016 2018 202012

14

16

18

20

22

24

26

28

30

32

34

>20% sub-module eff.towards 25% cell eff.

16.8% at ZSW

16.9% at Empa

21.7% at ZSW

20.4% at Empa

Project goal

Project goal

Record

effic

iency v

alu

es [%

]

Year

Low temperature

process

High temperature

process

Shockley-Queisser limit

+ 1% by advanced light management

+ 2% by introducing novel concepts for

surfaces and interfaces

+ 1% by highly efficient CIGS absorber material

Start of project

© Sharc25

Sharc25 consortium

• Partners: 11

• Countries: 8

• Coordinator: ZSW

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• 5 R&D partners

• 4 universities

• 1 company

• 1 SME

NICE

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Bulk properties of CIGS with alkali metal post-deposition treatment (PDT)

Results of the Sharc25 project

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Alkali post-deposition treatment (PDT) of CIGS absorber

• PDT process under selenium atmosphere before buffer deposition

• Typically with alkali metal salts like KF (alternatively: RbF or CsF)

Na

- A. Chirila et al., Nat. Mater. 12 (2013) 1107

- A. Laemmle et al., Phys. Stat. Sol. (RRL) 9

(2013) 631

- P. Reinhard et al., Chem. Mater. 27 (2015) 5755

Review articles:

- P. M. P. Salomé et al., Sol. Energy Mater.

Sol. Cells 143 (2015) 9

- O. Kiowski et al., PV International 29 (2015) 76

KF PDT Na from substrate

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Alkali post-deposition treatment (PDT) of CIGS absorber

• PDT process under selenium atmosphere before buffer deposition

• Typically with alkali metal salts like KF (alternatively: RbF or CsF)

→ Boost in efficiency h due to increase in open-circuit voltage VOC

- A. Chirila et al., Nat. Mater. 12 (2013) 1107

- A. Laemmle et al., Phys. Stat. Sol. (RRL) 9

(2013) 631

- P. Reinhard et al., Chem. Mater. 27 (2015) 5755

Review articles:

- P. M. P. Salomé et al., Sol. Energy Mater.

Sol. Cells 143 (2015) 9

- O. Kiowski et al., PV International 29 (2015) 76

h VOC

50 cells 50 cells

Improvement in CIGS cell efficiency: h = 22.6%

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P. Jackson et al., Phys. Stat. Sol. (RRL) 10 (2016) 583

• CIGS with RbF-PDT

• Thin solution-grown CdS

• (Zn,Mg)O/ZnO:Al

with ARC

2006 2008 2010 2012 2014 2016 2018 202012

14

16

18

20

22

24

26

28

30

32

34

>20% sub-module eff.towards 25% cell eff.

16.8% at ZSW

16.9% at Empa

21.7% at ZSW

20.4% at Empa

Project goal

Project goal

Record

effic

iency v

alu

es [%

]

Year

Low temperature

process

High temperature

process

Shockley-Queisser limit

+ 1% by advanced light management

+ 2% by introducing novel concepts for

surfaces and interfaces

+ 1% by highly efficient CIGS absorber material

Start of project

© Sharc25

Goal of Sharc25 project:

Push CIGS thin-film solar cell efficiency towards 25%

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22.0% 22.6%

Benefit for industrial Sharc25 partners: NICE and Flisom

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Full-size CIGS module fabricated at

NICE Solar Energy on glass substrate

• Deposition processes: evaporation, sputtering, and

solution growth are feasible in industrial environment

• Deep insights into highly efficient CIGS solar cells:

- advanced characterization methods

- density functional modeling and device simulation

Benefit for industrial Sharc25 partners: NICE and Flisom

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Full-size CIGS module fabricated at

NICE Solar Energy on glass substrate

• Deposition processes: evaporation, sputtering, and

solution growth are feasible in industrial environment

• Deep insights into highly efficient CIGS solar cells:

- advanced characterization methods

- density functional modeling and device simulation

→ Knowledge-driven development and improvement

of CIGS absorber and important interfaces

• Cross-checks of lab-scale processes onto industrially

produced material, assessment of new processes and

materials → transferability to industrial applications

• Non-successful approaches can be omitted

Potential for cost reduction due to

increased module efficiencies

Benefit for industrial Sharc25 partners: NICE and Flisom

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R2R

Full-size CIGS module fabricated

at Flisom on flexible substrate

Example: Post-deposition treatment (PDT)

• Beneficial effect of alkali PDT worldwide

- on cell and module level

- for different absorbers:

Cu(In,Ga)Se2 and Cu(In,Ga)(S,Se)2

- for both process routes: co-evaporation

(Sharc25) and sequential process

• Transfer of alkali metal PDT

to industrial environment

→ TRL 8 - 9

Potential for cost reduction due to

increased module efficiencies

Summary

• Post-deposition treatment (PDT) with KF, RbF or CsF enhances h

• Deep insights by complementary approaches

• Knowledge-driven development and improvement of CIGS solar cells

• CIGS thin-film solar cell: 22.6% efficiency with RbF-PDT

Benefit for industrial partners

• Detailed assessment of new process and material developments

for potential industrial application

• Implementation and positive impact of alkali metal PDT process at

industrial partners Flisom and NICE Solar Energy demonstrated

• Potential for cost reduction due to higher module efficiencies

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Papers published by Sharc25 consortium (www.sharc25.eu)

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2018

• M. H. Wolter et al., IEEE J. Photovolt. 8 (2018) 1320

• F. Werner et al., accepted in Prog. Photovolt. Res. Appl. (2018), DOI: 10.1002/pip.3032

• B. Bissig et al., accepted in Prog. Photovolt. Res. Appl. (2018), DOI: 10.1002/pip.3029

• R. Carron et al., Sci. Technol. Adv. Mater. 19 (2018) 396

• A. Vilalta-Clemente et al., Appl. Phys. Lett. 112 (2018) 103105

• J. Löckinger et al., Sol. Energy Mater. Sol. Cells 174 (2018) 397

• T. P. Weiss et al., Adv. Mater. Interfaces 5 (2017) 1701007

2017

• N. Nicoara et al., ACS Appl. Mater. Interfaces 9 (2017) 44173

• W. Witte et al., Phys. Stat. Sol. A 214 (2017) 1700688

• T. P. Weiss et al., Phys. Chem. Chem. Phys. 19 (2017) 30410

• M. Malitckaya et al., J. Phys. Chem. C 121 (2017) 15516

• M. Malitckaya et al., Adv. Electron. Mater. 3 (2017) 1600353

• G. Sozzi et al., Solar Energy Mater. Sol. Cells 165 (2017) 94

• M. H. Wolter et al., Phys. Stat. Sol. C 14 (2017) 1600189

• E. Handick et al., ACS Appl. Mater. Interfaces 9 (2017) 3581

• E. Avancini et al., Prog. Photovolt. Res. Appl. 25 (2017) 233

2016

• P. Jackson et al. Phys. Stat. Sol. (RRL) 10 (2016) 583

• G. Sozzi et al., Proc. 43rd IEEE PVSC, Portland, OR, USA, 2016, p. 2283

• G. Sozzi et al., Proc. 43rd IEEE PVSC, Portland, OR, USA, 2016, p. 2279

• E. Handick et al., Proc. 43rd IEEE PVSC, Portland, OR, USA, 2016, p. 0017

Sharc25 sponsored workshop

CIGS solar cells - advanced characterization and novel concepts

Date: October 29, 2018

Aim & Scope: Learn about the advancements made through the Sharc25 project

Listen to possible approaches for achieving efficiencies towards 25%

Learn about advance characterization methods for industrial benefits

Discuss with experts from the consortium and with external speakers

Interaction of academia and industry to identify topical research themes

Venue: Empa Dübendorf, Switzerland (close to Zurich airport)

Costs: free but online registration required until October 12, 2018

Contact: stephan.buecheler@empa.ch

More info: www.empa-akademie.ch/sharc25

Acknowledgement

• This project has received funding from the European Union’s Horizon

2020 research and innovation program under grant agreement

No 641004 (Sharc25).

• This work was supported by the Swiss State Secretariat for Education,

Research and Innovation (SERI) under contract number 15.0158.

The opinions expressed and arguments employed herein do not

necessarily reflect the official views of the Swiss Government.

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Thank you for your attention

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Info: Wolfram Witte

Website: www.sharc25.eu

Email: wolfram.witte@zsw-bw.de

Public Sharc25 workshop at Empa, Dübendorf (CH) on October 29, 2018

www.empa-akademie.ch/sharc25