Seed wafer, porosified wafer and epitaxially grown Si layer (from left to right).

Feedstock, Crystallization and Wafering

R&D Services

Our R&D services comprise:

Feedstock Analysis and Qualification

Technology and Characterization

Advancements in silicon materials for photovoltaics are most efficient when achieved throughout the entire production chain. The opportunities afforded by the silicon materials platform established by our team at Fraunhofer ISE in 2011, allow us to model all process steps from mono- and multicrystalline ingot crystallization to block shaping, polishing and wafering. We are thus able to offer skilled, comprehensive characterization of all the different process steps involved from the feedstock through to the finished solar cell under one roof.

Our research aims to develop silicon crystals and silicon wafers for solar cells that are of the highest quality and the lowest cost. In order to achieve this, innovative approaches are adopted in the crystallization process to minimize the introduction of impurities and defects, and processes and equipment are developed for increased throughput. In relation to wafering, we research diamond wire and slurry-based sawing processes for outstanding cutting performance, minimum kerf losses and optimum wafer surfaces.

The high levels of expertise that we employ for the benefit of our clients are demonstrated by multicrystalline wafers manufactured in block casting processes that exhibit solar cell efficiencies of up to 20%, and wafer thicknesses of under 70 µm.

Crystallisation facility to produce multicrystalline silicon ingots.
© Fraunhofer ISE

Crystallisation facility to produce multicrystalline silicon ingots.

    Silicon Material TEChnology research center

Selected Research Projects



Unlimited, Resource-saving Solar Cells Based on Metallurgical-grade Silicon



Silicon Wafer Production with Diamond-coated Sawing Wire



Basic Examination of Diamond-coated Sawing Wire Processes and Wafer Qualities


Current publications of the research topic Feedstock, Crystallization and Wafering:

YearTitle/AuthorDocument Type
2017Approaching 22% efficiency with multicrystalline n-type silicon solar cells
Benick, J.; Müller, R.; Schindler, F.; Richter, A.; Hauser, H.; Feldmann, F.; Krenckel, P.; Riepe, S.; Schubert, M.C.; Hermle, M.; Glunz, S.W.
Conference Paper
2017Characterization of the diamond wire sawing process for monocrystalline silicon by raman spectroscopy and SIREX polarimetry
Würzner, S.; Herms, M.; Kaden, T.; Möller, H.J.; Wagner, M.
Journal Article
2017Determination of impurity distributions in ingots of solar grade silicon by neutron activation analysis
Karches, B.; Schön, J.; Gerstenberg, H.; Hampel, G.; Krenckel, P.; Plonka, C.; Ponsard, B.; Riepe, S.; Stieghorst, C.; Wiehl, N.
Journal Article
2017Feeding of liquid silicon for high performance multicrystalline silicon with increased ingot height and homogenized resistivity
Krenckel, P.; Riepe, S.; Schindler, F.; Strauch, T.
Journal Article
2017Growth of large scale silicon crystals by the rf-heated float zone technique
Zobel, F.; Mosel, F.; Störensen, J.; Dold, P.
Conference Paper
2017High-Efficiency n-Type HP MC Silicon Solar Cells
Benick, J.; Richter, A.; Müller, R.; Hauser, H.; Feldmann, F.; Krenckel, P.; Riepe, S.; Schindler, F.; Schubert, M.C.; Hermle, M.; Bett, A.W.; Glunz, S.W.
Journal Article
2017How to achieve efficiencies exceeding 22% with multicrystalline n-type silicon solar cells
Schindler, F.; Michl, B.; Krenckel, P.; Riepe, S.; Benick, J.; Müller, R.; Richter, A.; Glunz, S.W.; Schubert, M.C.
Journal Article
2017The influence of material properties on the wire sawing process of multicrystalline silicon
Kaden, T.; Ershova, E.; Lottspeich, L.; Fuchs, M.
Conference Paper
2017Instrumental determination of phosphorus in silicon for photovoltaics by β spectroscopy: A new approach
Karches, B.; Welter, K.; Stieghorst, C.; Wiehl, N.; Reich, T.; Riepe, S.; Krenckel, P.; Gerstenberg, H.; Plonka, C.
Journal Article
2017A novel approach to determine the diamond occupancy of diamond wires for optimized cutting processes for crystalline silicon
Lottspeich, L.; Theophil, L.; Fuchs, M.; Kaden, T.
Conference Paper
2017Optimized multicrystalline silicon for solar cells enabling conversion efficiencies of 22%
Schindler, F.; Michl, B.; Krenckel, P.; Riepe, S.; Benick, J.; Müller, R.; Richter, A.; Glunz, S.W.; Schubert, M.C.
Journal Article
2017Rapid vapor-phase direct diffused emitter for solar cell applications
Kühnhold-Pospischil, S.; Gust, E.; Amiri, D.; Richter, A.; Steinhauser, B.; Drießen, M.; Michl, B.; Greulich, J.; Benick, J.; Lindekugel, S.; Janz, S.
Conference Paper
2016Changes of solar cell parameters during damp-heat exposure
Zhu, J.; Koehl, M.; Hoffmann, S.; Berger, K.A.; Zamini, S.; Bennett, I.; Gerritsen, E.; Malbranche, P.; Pugliatti, P.; Di Stefano, A.; Aleo, F.; Bertani, D.; Paletta, F.; Roca, F.; Graditi, G.; Pellegrino, M.; Zubillaga, O.; Iranzo, F.J.C.; Pozza, A.; Sample, T.; Gottschalg, R.
Journal Article
2016Cost Effective Growth of Silicon Mono Ingots by the Application of a Mobile Recharge System in CZ-Puller
Mosel, F.; Denisov, A.V.; Klipp, B.; Spill, B.; Sharma, R.; Kunert, R.; Dold, P.
Conference Paper
2016Effect of thermal insulation of the back side of PV modules in the module temperature
Koehl, M.; Hamperl, S.; Heck, M.
Journal Article
2016Impact of rain and soiling on potential induced degradation
Köhl, M.; Hoffmann, S.
Journal Article
2016Improving the material quality of silicon ingots by aluminum gettering during crystal growth
Schön, J.; Krenckel, P.; Karches, B.; Schindler, F.; Giesecke, J.; Stieghorst, C.; Wiehl, N.; Schubert, M.C.; Riepe, S.
Journal Article
2016Insights into metastability of photovoltaic materials at the mesoscale through massive I-V analytics
Peshek, T.J.; Fada, J.S.; Hu, Y.; Xu, Y.; Elsaeiti, M.A.; Schnabel, E.; Köhl, M.; French, R.H.
Journal Article
2016N-type multicrystalline silion for high efficiency solar cells
Riepe, S.; Krenckel, P.; Schindler, F.; Schubert, M.; Benick, J.
Journal Article
2015Manufacturing 100-µm-thick silicon solar cells with efficiencies greater than 20% in a pilot production line
Terheiden, B.; Ballmann, T.; Horbelt, R.; Schiele, Y.; Seren, S.; Ebser, J.; Hahn, G.; Mertens, V.; Koentopp, M.B.; Scherff, M.; Müller, J.W.; Holman, Z.C.; Descoeudres, A.; Wolf, S. de; Nicolas, S.M. de; Geissbuehler, J.; Ballif, C.; Weber, B.; Saint-Cast, P.; Rauer, M.; Schmiga, C.; Glunz, S.W.; Morrison, D.J.; Devenport, S.; Antonelli, D.; Busto, C.; Grasso, F.; Ferrazza, F.; Tonelli, E.; Oswald, W.
Journal Article
2015Resistivity, doping concentrations, and carrier mobilities in compensated N- and P-type Czochralski silicon: Comparison of measurements and simulations and consistent description of material parameters
Broisch, J.; Schindler, F.; Schubert, M.C.; Fertig, F.; Soiland, A.-K.; Rein, S.
Journal Article
2015Solarenergie zur Stromerzeugung
Kiefer, K.
Book Article
2014Challenges for photovoltaic silicon materials
Coletti, G.; Gordon, I.; Schubert, M.C.; Warta, W.; Ovrelid, E.J.; Jouini, A.; Tucci, M.; Cesare, G. de
Journal Article
2014Imaging as-grown interstitial iron concentration on boron-doped silicon bricks via spectral photoluminescence
Mitchell, B.; Macdonald, D.; Schön, J.; Weber, J.; Wagner, H.; Trupke, T.
Journal Article
2014Influence of high aluminium content on the mechanical properties of directionally solidified multicrystalline silicon
Orellana, T.; Tejado, E.M.; Funke, C.; Riepe, S.; Pastor, J.Y.; Möller, H.J.
Journal Article
This publication list has been generated from the publication database Fraunhofer-Publica.