Si-Materials workshop, Rome, October 7-8, 2013


Challenges for Photovoltaic Silicon Materials

The aim of this workshop is to exchange results, views and opinions between people from universities, R&D institutes and industries on the new challenges for PV Si materials and to discuss a common Si roadmap for the PV industry.
In particular we would like to discuss the following questions:

  • What are the new materials requirements for innovative solar cell concepts?
  • How can Si materials contribute to the technological development of Photovoltaic (PV) and support the PV industry?
  • What are the current challenges PV Si materials face?

These and other questions will be addressed in a two days workshop. Participants are invited to submit a contribution and to play an active role during the discussions.

This workshop is a follow-up of the successful Si-Materials workshop, organized in 2008 in Amsterdam, focused on solar-grade feedstock specifications. In the last 5 years, PV technology and economics have changed considerably and it’s now time to define a roadmap for Si PV materials challenges.

Special section of the Silicon Materials workshop published in Solar Energy Materials and Solar Cells

The results of the workshop on Silicon Materials have been published in a special section of Solar Energy Materials and Solar Cells. The contributions with highest ranking have been given the opportunities to write a peer review paper published in this section. The section starts with an editorial for the journal written by the chairman and the organizing committee, titled: “Challenges for photovoltaic silicon materials”.


Solar Energy Materials and Solar Cells, Volume 130, November 2014, from page 629.




08:30 - 09:30



09:30 – 09:40

Welcome and introduction (Gianluca Coletti, Giampiero de Cesare)


09:40 – 11:00

Session 1: Status and future prospects for Si Materials
(Chairmen: Ivan Gordon, Bruno Ceccaroli)


Solar grade silicon: technology status and industrial trends

Gøran Bye (Advanced Materials Management Solutions, LLC)


Prospects and challenging of kerfless silicon

Tonio Buonassisi (MIT)

ITRPV - perspective for PV Si materials

Stephan Raithel (Director PV Europe, SEMI Europe)

Wrap up

11:00 – 11:30

Coffee break


11:30 – 12:50

Session 2: Material requirements
(Chairmen: Gabriella Tranell, Carlos del Cañizo)


First results from a simplified Elkem Solar route – input to tolerance limits

Anne-Karin Søiland (Elkem Solar)


Resistivity and lifetime requirements and light induced enhancement in n-type silicon solar cells

Ajeet Rohatgi (Georgia Institute of Technology)


Low cost interdigitated back-contact solar cells for high yield cell production: choosing the material quality for high energy conversion efficiency.

Giuseppe Galbiati (ISC Konstanz)


Wrap up


12:50 – 14:10



14:10 – 15:40

(Chairmen: Gianluca Coletti, Ivan Gordon)

Discussion online survey

Panel discussion with experts

15:40 – 17:00

Poster session and coffee break


17:00 – 18:40

Session 3: Characterization and control techniques

(Chairmen: Wilhelm Warta, Marisa Di Sabatino)


Toward a fast and accurate determination of dopants concentrations in solar grade silicon

Benoit Martel (CEA-INES)


Feedstock trace element load vs. cell efficiency

Sylke Meyer (Fraunhofer CSP)


Photoluminescence and infrared spectroscopy for the identification of defects in silicon for photovoltaic applications

Simona Binetti (Department of Materials Science and Mibsolar center University of Milano Bicocca)


The sub-surface damage of mc- and cz-Si wafers sawn with diamond-coated wire

Rajko Buchwald (Fraunhofer THM)


Wrap up


18:40 – 19:00

Short summary, day wrap up


19:15 – 20:00

Visit of Basilica of San Pietro in Vincoli (


20:15 – 22:30

Dinner event Roof Garden Hotel Forum
(Address: Via Tor Dei Conti, 31, 00184 Rome)





09:00 – 09:30



09:30 – 12:00

Session 4: Challenges for p-type wafers
(Chairmen: Anis Jouini, Fabrizio Dughiero)


Analysis of the dislocation density in crystalline silicon for solar cells by the casting process

Satoshi Nakano (Research Institute for Applied Mechanics, Kyushu University)


Study of evolution of dislocation clusters in high performance multicrystalline silicon

Gaute Stokkan (Sintef)


Results on performance and ageing of solar modules based on Elkem Solar Silicon (ESS™) from installations at various locations

Jan Ove Odden (Elkem AS Solar)


Coffee break (10:30 - 11:00)


Directional crystalline growth based on seeds in critical state

Quanzhi Wang (Yingli)


Characterization of a 75 kg mc-Si ingot grown in a KRISTMAG ®-type G2 DS-furnace

Dieter Linke (IKZ)


Wrap up


12:00 – 13:30



13:30 – 15:10

Session 5: Challenges for n-type wafers
(Chairman: Gianluca Coletti, Valentin Mihailetchi)


The production of ideal substrates for n-type solar cells with a continuous Czochralski growth process

Bayard Johnson (GT Advanced Technologies)


Removing the effect of striations on n-type silicon solar cells

Petra Manshanden (ECN)


Advanced process for monolike silicon: a-Si:H/c-Si heterojunction solar cells with 21.5% efficiency

Frédéric Jay (CEA-INES)


Formation of oxygen precipitates in CZ-silicon during thermal annealing

Mari Juel (Sintef)


Wrap up


15:10 – 15:40

Workshop wrap up (Organizing Committee)


15:40 – 16:10

Coffee break and closing