Photo Dirk Mahler, © Fraunhofer ISE


  • H-Index(Google Scholar): 54
  • Patents: 27
  • citations Google Scholar: 12.620
  • 360 scientific publications
  • 130 peer review journal articles
  • 8 book chapters
  • 27 patent families

Professional Experience

Since 2007      Head of department “III-V Photovoltaics and Concentrator Technology” at Fraunhofer ISE, Freiburg, Germany

Since 2001      Scientist at Fraunhofer ISE working on tandem-photovoltaics, space solar cells, concentrating photovoltaics, solar hydrogen

2000 – 2001     PostDoc in the group of Prof. G. Stringfellow, Univ. of Utah, Salt Lake City, U.S.A. supported by the German Science Foundation 

1996 – 2000     Dissertation “Metal organic vapour phase epitaxy for the fabrication of high efficiency solar cells from III-V semiconductors” at

                      Fraunhofer ISE and Univ. Konstanz.

1995                Internship at Paul-Scherrer Institute in Zurich: "Capacitance measurement of the open circuit voltage decay in solar cells"

1990 – 1996     Studies of physics, mathematics and philosophy at the University of Zurich, Switzerland

Honors and Awards

2021                Board member of the Wiley open access journal Applied Research

2018                GreenTec Award Finalist in the category Energy

2015                World Technology Award

2013-2022        Editor, IEEE Journal of Photovoltaics in the area of III-V, Concentrator and Space PV

2011                French-German Economy Award

2010                Grand Prix Scientifique, Foundation Louis D (highest endowed French science award by the Institut de France, Paris)

2010                Fraunhofer Award

2005                Co-founder of the company Concentrix Solar, later Soitec Solar with manufacturing of CPV modules in Freiburg and San Diego

Selected Publications

P. Schygulla, R. Müller, D. Lackner, O. Höhn, H. Hauser, B. Bläsi, F. Predan, J. Benick, M. Hermle, S. W. Glunz, and F. Dimroth, “Two‐terminal III–V//Si triple‐junction solar cell with power conversion efficiency of 35.9 % at AM1.5g,” Prog Photovolt Res Appl., vol. 30, no. 8, pp. 869–879, 2022. This paper summarizes results of the currently most efficient III-V/Si tandem solar cell in the world.

R. Cariou, J. Benick, F. Feldmann, O. Höhn, H. Hauser, P. Beutel, N. Razek, M. Wimplinger, B. Bläsi, D. Lackner, M. Hermle, G. Siefer, S. W. Glunz, A. W. Bett, and F. Dimroth, “III–V-on-silicon solar cells reaching 33% photoconversion efficiency in two-terminal configuration” Nature Energy, vol. 3, no. 4, pp. 326–333, (2018). This is an earlier publication on the same topic.

M. Feifel, D. Lackner, J. Schön, J. Ohlmann, J. Benick, G. Siefer, F. Predan, M. Hermle, and F. Dimroth, “Epitaxial GaInP/GaAs/Si Triple‐Junction Solar Cell with 25.9% AM1.5g Efficiency Enabled by Transparent Metamorphic AlxGa1− xAsyP1− y Step‐Graded Buffer Structures,” Sol. RRL, vol. 5, no. 5, p. 2000763, (2021). In this paper,  all the III-V layers were grown directly onto the silicon bottom solar cell which is also a world record for such a device.

W.-H. Cheng, M. H. Richter, M. M. May, J. Ohlmann, D. Lackner, F. Dimroth, T. Hannappel, H. A. Atwater, and H.-J. Lewerenz, “Monolithic Photoelectrochemical Device for Direct Water Splitting with 19% Efficiency” ACS Energy Lett., (2018). This paper shows efficient splitting of water into hydrogen and oxygen by using a III-V tandem solar cells which is directly exposed to the electrolyte.

F. Dimroth, III-V solar cells – materials, multi-junction cells – cell design and performance (Ch 8.1), in Photovoltaic Solar Energy: From Fundamentals to Applications, Willey, ISBN: 978-1-118-92746-5 Editors: Angèle Reinders, Alexandre Freundlich & Pierre Verlinden, (2017).

M. Steiner, G. Siefer, T. Schmidt, M. Wiesenfarth, F. Dimroth, and A. W. Bett, “43% Sunlight to Electricity Conversion Efficiency Using CPV” IEEE J. Photovolt., vol. 6, no. 4, pp. 1020–1024, (2016). This paper presents world record performance for a small concentrating photovoltaic module.

R. M. France, F. Dimroth, T. J. Grassman, and R. R. King, “Metamorphic epitaxy for multijunction solar cells” MRS Bulletin, vol. 41, no. 03, pp. 202–209, (2016).

F. Dimroth, T. N. D. Tibbits, M. Niemeyer, F. Predan, P. Beutel, C. Karcher, E. Oliva, G. Siefer, D. Lackner, P. Fus-Kailuweit, A. W. Bett, R. Krause, C. Drazek, E. Guiot, J. Wasselin, A. Tauzin, and T. Signamarcheix, “Four-Junction Wafer-Bonded Concentrator Solar Cells,” IEEE J. Photovolt., vol. 6, no. 1, pp. 343–349, (2016). World record performance concentratrator solar cell with 46.1% efficiency.

J. Wallentin, N. Anttu, D. Asoli, M. Huffman, I. Aberg, M.H. Magnusson, G. Siefer, P. Fuss-Kailuweit, F. Dimroth, B. Witzigmann, H.Q. Xu, L. Samuelson, K. Deppert and M.T. Borgström, InP Nanowire Array Solar Cells Achieving 13.8% Efficiency by Exceeding the Ray Optics Limit, Science, 2013. 339(6123): p. 1057-1060. World record performance for a nano-wire solar cell.


Fraunhofer ISE

Department III-V Epitaxy and Solar Cells