Business card

Dr. Christian Kaufmann

Dr. Christian Kaufmann

Principal Scientist CIGS @ PVcomB
Institute Competence Centre Photovoltaics Berlin (PVcomB)

Tel (030) 8062 - 18143, (030) 8062 - 42737 Fax (030) 8062 - 15677 mail

Selected Publications


Heinemann, M.D.; Ruske, F.; Greiner, D.; Jeong, A.R.; Rusu, M.; Rech, B.; Schlatmann, R.; Kaufmann, C.A.: Advantageous light management in Cu(In,Ga)Se2 superstrate solar cells. Solar Energy Materials and Solar Cells 150 (2016), p. 76-81


Harndt, S.; Kaufmann, C.A.; Lux-Steiner, M.C.; Klenk, R.; Nürnberg, R.: Grain boundary assisted photocurrent collection in thin film solar cells. EPJ Photovoltaics 6 (2015), p. 60101-60105

Heinemann, M.D.; Efimova, V.; Klenk, R.; Hoepfner, B.; Wollgarten, M.; Unold, T.; Schock, H.-W.; Kaufmann, C.: Cu(In,Ga)Se2 Superstrate Solar Cells: Prospects and Limitations. Progress in Photovoltaics 23 (2015), p. 1228–1237

Mainz, R.; Rodriguez Alvarez, H.; Klaus, M.; Thomas, D.; Lauche, J.; Weber, A.; Heinemann, M.D.; Brunken, S.; Greiner, D.; Kaufmann, C.A.; Unold, T.; Schock, H.-W.; Genzel, C.: Sudden stress relaxation in compound semiconductor thin films triggered by secondary phase segregation. Physical Review B 92 (2015), p. 155310/1-8

Merdes, S.; Steigert, A.; Ziem, F.; Lauermann, I.; Klenk, R.; Hergert, F.; Kaufmann, C.A.; Schlatmann, R.: Influence of Cu(In,Ga)(Se,S)2 surface treatments on the properties of 30 x 30 cm2 large area modules with atomic layer deposited Zn(O,S) buffers. Thin Solid Films 574 (2015), p. 28-31

Ohm, W.; Riedel, W.; Askünger, Ü.; Heinemann, M.D.; Kaufmann, C.; Lopez Garzia, J.; Izqierdo, V.; Fontane, X.; Goislard, T.; Lux-Steiner, M.Ch.; Gledhill, S.: An overview of technological aspects of Cu(In,Ga)Se2 solar cell architectures incorporating ZnO nanorod arrays. Physica Status Solidi A 212 (2015), p. 76–87

Schnohr, C.S.; Kämmer, H.; Steinbach, T.; Gnauck, M.; Rissom, T.; Kaufmann, C.A.; Stephan, C.; Schorr, S.: Composition-dependent nanostructure of Cu(In,Ga)Se2 powders and thin films. Thin Solid Films 582 (2015), p. 356-360

Wakefield, G.; Adair, M.; Gardener, M.; Greiner, D.; Kaufmann, C.A.; Moghal, J.: Mesoporous silica nanocomposite antireflective coating for Cu(In,Ga)Se2 thin film solar cells. Solar Energy Materials and Solar Cells 134 (2015), p. 359–363

Ümsür, B.; Calvet, W.; Höpfner, B.; Steigert, A.; Lauermann, I.; Gorgoi, M.; Prietzel, K.; Navirian, H.; Kaufmann, C.; Unold, T.; Lux-Steiner, M.: Investigation of Cu-poor and Cu-rich Cu(In,Ga)Se2/CdS interfaces using hard X-ray photoelectron spectroscopy. Thin Solid Films 582 (2015), p. 366-370


Caballero, R.; Nichterwitz, M.; Steigert, A.; Eicke, A.; Lauermann, I.; Schock, H.W.; Kaufmann, C.A.: Impact of Na on MoSe2 formation at the CIGSe/Mo interface in thin-film solar cells on polyimide foil at low process temperatures. Acta Materialia 63 (2014), p. 54-62

Kaufmann, C.A.; Greiner, D.; Harndt, S.; Klenk, R.; Brunken, S.; Schlatmann, R.; Nichterwitz, M.; Schock, H.-W.; Unold, T.; Zajac, K.; Brunner, S.; Daume, F.; Scheit, C.; Puttnins, S.; Braun, A.; Rahm, A.; Wuerz, R.; Kessler, F.; Guenthner, M.; Pscherer, M.; Ihlow, S.; Motz, G.; Morgner, H.; G., R.; Lambrecht, A.; T., J.; Spietz, P.; Schülke, P.: FLEXIBLE Cu(In,Ga)Se2 THIN FILM SOLAR CELLS FOR SPACE APPLICATIONS - RECENT RESULTS FROM A GERMAN JOINT PROJECT (PIPV2). In: T. P. Bokhoven ... [Ed.] : 29th European PV Solar Energy Conference and Exhibition : proceedings of the international conference held in Amsterdam, The Netherlands, 22 - 26 September 2014. München: WIP, 2014. - ISBN 3-936338-34-5, p. 1439 - 1443

Klenk, R.; Steigert, A.; Rissom, T.; Greiner, D.; Kaufmann, C.A.; Unold, T.; Lux-Steiner, M.Ch.: Junction formation by Zn(O,S) sputtering yields CIGSe-based cells with efficiencies exceeding 18%. Progress in Photovoltaics 22 (2014), p. 161-165


Caballero, R.; Kaufmann, C.A.; Efimova, V.; Rissom, T.; Hoffmann, V.; Schock, H.W.: Investigation of Cu(In,Ga)Se2 thin-film formation during the multi-stage co-evaporation process. Progress in Photovoltaics 21 (2013), p. 30-46

Nichterwitz, M.; Caballero, R.; Kaufmann, C.A.; Schock, H.-W.; Unold, T.: Generation-dependent charge carrier transport in Cu(In,Ga)Se2/CdS/ZnO thin-film solar-cells. Journal of Applied Physics 113 (2013), p. 044515/1 -16

Rodriguez-Alvarez, H.; Barreau, N.; Kaufmann, C.A.; Weber, A.; Klaus, M.; Painchaud, T.; Schock, H.-W.; Mainz, R.: Recrystallization of Cu(In,Ga)Se2 thin films studied by X-ray diffraction. Acta Materialia 61 (2013), p. 4347-4353

Rodriguez-Alvarez, H.; Mainz, R.; Caballero, R.; Abou-Ras, D.; Klaus, M.; Gledhill, S.; Weber, A.; Kaufmann, C.A.; Schock, H.-W.: Real-time study of Ga diffusion processes during the formation of Cu(In,Ga)Se2: The role of Cu and Na content. Solar Energy Materials and Solar Cells 116 (2013), p. 102-109

Rodriguez-Alvarez, H.; Weber, A.; Lauche, J.; Kaufmann, Ch.A.; Rissom, T.; Greiner, D.; Klaus, M.; Unold, Th.; Genzel, C.; Schock, H.-W.; Mainz, R.: Formation of CuInSe2 and CuGaSe2 thin films deposited by three-stage thermal co-evaporation: a real-time x-ray diffraction and fluorescence study. Advanced Energy Materials 3 (2013), p. 1381-1387


Eisenbarth, T.; Caballero, R.; Kaufmann, C.A.; Eicke, A.; Unold, T.: Influence of iron on defect concentrations and device performance for Cu(In,Ga)Se2 solar cells on stainless steel substrates. Progress in Photovoltaics 20 (2012), p. 568-574

Stephan, C.; Scherb, T.; Kaufmann, C.A.; Schorr, S.; Schock, H.-W.: Cationic point defects in CuGaSe2 from a structural perspective. Applied Physics Letters 101 (2012), p. 101907/1-4


Abou-Ras, D.; Caballero, R.; Fischer, C.-H.; Kaufmann, C.A.; Lauermann, I.; Mainz, R.; Mönig, H.; Schöpke, A.; Stephan, C.; Streeck, C.; Schorr, S.; Eicke, A.; Döbeli, M.; Gade, B.; Hinrichs, J.; Nunney, T.; Dijkstra, H.; Hoffmann, V.; Klemm, D.; Efimova, V.; Bergmaier, A.; Dollinger, G.; Wirth, T.; Unger, W.; Rockett, A.A.; Perez-Rodriguez, A.; Alvarez-Garcia, J.; Izquierdo-Roca, V.; Schmid, T.; Choi, P.-P.; Müller, M.; Bertram, F.; Christen, J.; Khatri, H.; Collins, R. W.; Marsillac, S.; Kötschau, I.: Comprehensive Comparison of Various Techniques for the Analysis of Elemental Distributions in Thin Films. Microscopy and Microanalysis 17 (2011), p. 728-751

Caballero, R.; Kaufmann, Ch. A.; Eisenbarth, T.; Unold, Th.; Klenk, R.; Schock, H.-W.: High efficiency low temperature grown Cu(In,Ga)Se2 thin film solar cells on flexible substrates using NaF precursor layers. Progress in Photovoltaics 19 (2011), p. 547-551

Eisenbarth, T.; Caballero, R.; Nichterwitz, M.; Kaufmann, C.A.; Schock, H.W.; Unold, T.: Characterization of metastabilities in Cu(In,Ga)Se2] thin-film solar cells by capacitance and current-voltage spectroscopy. Journal of Applied Physics 110 (2011), p. 094506/1-13

Haarstrich, J.; Metzner, H.; Oertel, M.; Ronning, C.; Rissom, T.; Kaufmann, C.A.; Unold, T.; Schock, H.W.; Windeln, J.; Mannstadt, W.; Rudigier-Voigt, E.: Increased homogeneity and open-circuit voltage of Cu(In,Ga)Se2 solar cells due to higher deposition temperature. Solar Energy Materials and Solar Cells 96 (2011), p. 1028-1030

Hoffmann, V.; Klemm, D.; Efimova, V.; Venzago, C.; Rockett, A.A.; Wirth, T.; Nunney, T.; Kaufmann, C.A.: Elemental Distribution Profiling of Thin Films for Solar Cells. In: Rau, Abou-Ras, Kirchartz [Ed.] : Advanced characterization techniques for thin film solar cells. Wiley, 2011. - ISBN 3-527-41003-1, p. 411-448

Rissom, T.; Mainz, R.; Kaufmann, C.A.; Caballero, R.; Efimova, V.; Hoffmann, V.; Schock, H.-W.: Examination of growth kinetics of copper rich Cu(In,Ga)Se-2-films using synchrotron energy dispersive X-ray diffractometry. Solar Energy Materials and Solar Cells 95 (2011), p. 250-253


Caballero, R.; Kaufmann, C.A.; Eisenbarth,T.; Grimm, A.; Lauermann, I.; Unold, T.; Klenk, R.; Schock, H.W.;: Influence of Na on Cu(In,Ga)Se2 solar cells grown on polyimide substrates at low temperature: Impact on the Cu(In,Ga)Se2/Mo interface. Applied Physics Letters 96 (2010), p. 092104/1-3

Eisenbarth, T.; Unold, T.; Caballero, R.; Kaufmann, C.A.; Schock, H.-W.: Interpretation of admittance, capacitance-voltage, and current-voltage signatures in Cu(In,Ga)Se2 thin film solar cells. Journal of Applied Physics 107 (2010), p. 034509/1-12

Mönig, H.; Fischer, Ch.-H.; Grimm, A.; Johnson, B.; Kaufmann, C.A.; Caballero, R.; Lauermann, I.; Lux-Steiner, M.Ch.: Surface Cu-depletion of Cu(In,Ga)Se-2 thin films: Further experimental evidence for a defect-induced surface reconstruction. Journal of Applied Physics 107 (2010), p. 113540/1-5


Kaufmann, C.; Caballero, R.; Unold, T.; Hesse, R.; Klenk, R.; Schorr, S.; Nichterwitz, M.; Schock, H.-W.: Depth profiling of Cu(In,Ga)Se2 thin films grown at low temperatures. Solar Energy Materials and Solar Cells 93 (2009), p. 859-863

Moenig, H.; Fischer, Ch.-H.; Caballero, R.; Kaufmann, C.A.; Allsop, N.; Gorgoi, M.; Klenk, R.; Schock, H.-W.; Lehmann, S.; Lux-Steiner, M.C.; Lauermann, I.: Surface Cu depletion of Cu(In,Ga)Se-2 films: An investigation by hard X-ray photoelectron spectroscopy. Acta Materialia 57 (2009), p. 3645-3651


Kaufmann, C.A. ; Unold, T. ; Abou-Ras, D. ; Bundesmann, J. ; Neisser, A. ; Klenk, R. ; Scheer, R. ; Sakurai, K. ; Schock, H.-W.: Investigation of coevaporated Cu(In,Ga)Se2 thin films in highly efficient solar cell devices. Thin Solid Films 515 (2007), p. 6217-6221

Sakurai, K.; Neumann, T.; Hesse, R.; Abou-Ras, D.; Jablonski, P.; Neisser, A.; Kaufmann, C.; Niki, S.; Scheer, R.; Schock, H.W.: Characteristics of scattered laser light signals from Cu(In,Ga)Se-2 films. Thin Solid Films 515 (2007), p. 6222-6225


Kaufmann, C.A.; Neisser, A.; Klenk, R.; Scheer, R.: Transfer of Cu(In,Ga)Se2 thin film solar cells to flexible substrates using an in situ process control. Thin Solid Films 480-481 (2005), p. 515-519


Kaufmann C. ; Bayon R. ; Bohne W. ; Röhrich J. ; Klenk R. ; Dobson P.J.: Chemical bath deposition of indium oxyhydroxysulfide thin films. Journal of the Electrochemical Society 149 (2002), p. C1-C9