Veröffentlichungen
2017 |
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M. Rienäcker, M. Bossmeyer, A. Merkle, U. Römer, F. Haase, J. Krügener, R. Brendel, and R. Peibst IEEE Journal of Photovoltaics 7 (1), 11-18, (2017), ISSN: 2156-3381. Abstract | Links | BibTeX | Schlagwörter: Aluminum, Back-junction back-contact (BJBC) cells, boron, Conductivity, contact resistivity, Current density, Junctions, Photovoltaic cells, polysilicon, polysilicon on oxide (POLO) junctions, recombination, selective contacts, selectivity @article{Rienäcker2017b,
title = {Junction resistivity of carrier-selective polysilicon on oxide junctions and its impact on solar cell performance}, author = {M Rienäcker and M Bossmeyer and A Merkle and U Römer and F Haase and J Krügener and R Brendel and R Peibst}, doi = {10.1109/JPHOTOV.2016.2614123}, issn = {2156-3381}, year = {2017}, date = {2017-01-01}, journal = {IEEE Journal of Photovoltaics}, volume = {7}, number = {1}, pages = {11-18}, abstract = {We investigate the junction resistivity of high-quality carrier-selective polysilicon on oxide (POLO) junctions with the transfer length method. We demonstrate n+ POLO junctions with a saturation current density JC,poly of 6.2 fA/cm2 and a junction resistivity ρc of 0.6 mΩcm2, counterdoped n+ POLO junctions with 2.7 fA/cm2 and 1.3 mΩcm2, and p+ POLO junctions with 6.7 fA/cm2 and 0.2 mΩcm2. Such low junction resistivities and saturation current densities correspond to excellent selectivities S10 of up to 16.2. The efficiency potential for back-junction back-contact solar cells with these POLO junctions was determined to be larger than 25 % by numerical device simulations. We demonstrate experimentally a back-junction back-contact solar cell with p-type and n-type POLO junctions with an independently confirmed efficiency of 24.25 %.}, keywords = {Aluminum, Back-junction back-contact (BJBC) cells, boron, Conductivity, contact resistivity, Current density, Junctions, Photovoltaic cells, polysilicon, polysilicon on oxide (POLO) junctions, recombination, selective contacts, selectivity}, pubstate = {published}, tppubtype = {article} } We investigate the junction resistivity of high-quality carrier-selective polysilicon on oxide (POLO) junctions with the transfer length method. We demonstrate n+ POLO junctions with a saturation current density JC,poly of 6.2 fA/cm2 and a junction resistivity ρc of 0.6 mΩcm2, counterdoped n+ POLO junctions with 2.7 fA/cm2 and 1.3 mΩcm2, and p+ POLO junctions with 6.7 fA/cm2 and 0.2 mΩcm2. Such low junction resistivities and saturation current densities correspond to excellent selectivities S10 of up to 16.2. The efficiency potential for back-junction back-contact solar cells with these POLO junctions was determined to be larger than 25 % by numerical device simulations. We demonstrate experimentally a back-junction back-contact solar cell with p-type and n-type POLO junctions with an independently confirmed efficiency of 24.25 %.
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2016 |
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R. Brendel, and R. Peibst Contact selectivity and efficiency in crystalline silicon photovoltaics Artikel IEEE Journal of Photovoltaics 6 (6), 1413-1420, (2016). Abstract | Links | BibTeX | Schlagwörter: Contact resistance, Junctions, passivated emitter and rear cell (PERC), Photovoltaic cells, Photovoltaic systems, principle of solar cells, Resistance, selective contacts, silicon @article{Brendel2016b,
title = {Contact selectivity and efficiency in crystalline silicon photovoltaics}, author = {R Brendel and R Peibst}, doi = {10.1109/JPHOTOV.2016.2598267}, year = {2016}, date = {2016-11-01}, journal = {IEEE Journal of Photovoltaics}, volume = {6}, number = {6}, pages = {1413-1420}, abstract = {Highly doped junctions of a Si solar cell function as membranes that block minority carriers and, at the same time, provide a high conductivity for transporting majority carriers to the contacts. They are thus said to be selective contacts. We propose a quantitative definition for the selectivity of contacts. The selectivity provides a figure of merit for electron and hole contacts that is helpful in designing solar cells and in identifying the efficiency limiting components. Applying the definition of selectivity to poly-Si junctions reveals that the root cause of their high selectivity is the highly asymmetric carrier concentration rather than a specific contact geometry.}, keywords = {Contact resistance, Junctions, passivated emitter and rear cell (PERC), Photovoltaic cells, Photovoltaic systems, principle of solar cells, Resistance, selective contacts, silicon}, pubstate = {published}, tppubtype = {article} } Highly doped junctions of a Si solar cell function as membranes that block minority carriers and, at the same time, provide a high conductivity for transporting majority carriers to the contacts. They are thus said to be selective contacts. We propose a quantitative definition for the selectivity of contacts. The selectivity provides a figure of merit for electron and hole contacts that is helpful in designing solar cells and in identifying the efficiency limiting components. Applying the definition of selectivity to poly-Si junctions reveals that the root cause of their high selectivity is the highly asymmetric carrier concentration rather than a specific contact geometry.
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J. Krügener, D. Tetzlaff, Y. Larionova, Y. Barnscheidt, S. Reiter, M. Turcu, R. Peibst, J. -D. Kähler, and T. Wietler Electrical deactivation of boron in p+-poly/SiOx/crystalline silicon passivating contacts for silicon solar cells Inproceedings IEEE (Hrsg.): Proceedings of the 21st International Conference on Ion Implantation Technology (IIT), Tainan, Taiwan, (2016), ISBN: 978-1-5090-2025-6. Abstract | Links | BibTeX | Schlagwörter: Annealing, boron, Conductivity, Junctions, Resistance, silicon, Temperature measurement @inproceedings{Krügener2016,
title = {Electrical deactivation of boron in p+-poly/SiOx/crystalline silicon passivating contacts for silicon solar cells}, author = {J Krügener and D Tetzlaff and Y Larionova and Y Barnscheidt and S Reiter and M Turcu and R Peibst and J -D Kähler and T Wietler}, editor = {IEEE}, doi = {10.1109/IIT.2016.7882868}, isbn = {978-1-5090-2025-6}, year = {2016}, date = {2016-09-23}, booktitle = {Proceedings of the 21st International Conference on Ion Implantation Technology (IIT)}, journal = {Proceedings of the 21st International Conference on Ion Implantation Technology (IIT)}, address = {Tainan, Taiwan}, abstract = {Passivating junctions, like hole-collecting p+-polycrystalline silicon/SiOx/crystalline silicon junctions, need a thermal treatment to activate their excellent passivation and contact properties. Aside from surface passivation and from contact resistance between poly-Si and the substrate, the sheet resistance within the poly-Si is another important parameter for solar cell design. We present electrical investigations of in situ boron-doped (deposited by low pressure chemical vapor deposition) and ion-implanted (intrinsically deposited and subsequently ion-implanted with boron) p+-poly-Si/SiOx/c-Si stacks after annealing. We find electrical deactivation of boron after annealing which strongly depends on the total boron concentration and the subsequent annealing temperature.}, keywords = {Annealing, boron, Conductivity, Junctions, Resistance, silicon, Temperature measurement}, pubstate = {published}, tppubtype = {inproceedings} } Passivating junctions, like hole-collecting p+-polycrystalline silicon/SiOx/crystalline silicon junctions, need a thermal treatment to activate their excellent passivation and contact properties. Aside from surface passivation and from contact resistance between poly-Si and the substrate, the sheet resistance within the poly-Si is another important parameter for solar cell design. We present electrical investigations of in situ boron-doped (deposited by low pressure chemical vapor deposition) and ion-implanted (intrinsically deposited and subsequently ion-implanted with boron) p+-poly-Si/SiOx/c-Si stacks after annealing. We find electrical deactivation of boron after annealing which strongly depends on the total boron concentration and the subsequent annealing temperature.
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J. Krügener, Y. Larionova, B. Wolpensinger, D. Tetzlaff, S. Reiter, M. Turcu, R. Peibst, J. -D. Kähler, and T. Wietler Dopant diffusion from p+-poly-Si into c-Si during thermal annealing Inproceedings IEEE (Hrsg.): 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC), 2451-2454, Portland, OR, USA, (2016), ISBN: 978-1-5090-2725-5. Abstract | Links | BibTeX | Schlagwörter: Annealing, boron, diffusion, junction formation, Junctions, low pressure chemical vapor deposition, passivating contacts, Resistance, Scanning electron microscopy, silicon, Substrates, Temperature measurement @inproceedings{Krügener2016b,
title = {Dopant diffusion from p+-poly-Si into c-Si during thermal annealing}, author = {J Krügener and Y Larionova and B Wolpensinger and D Tetzlaff and S Reiter and M Turcu and R Peibst and J -D Kähler and T Wietler}, editor = {IEEE}, doi = {10.1109/PVSC.2016.7750083}, isbn = {978-1-5090-2725-5}, year = {2016}, date = {2016-06-01}, booktitle = {2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC)}, journal = {Proceedings of the 43rd IEEE Photovoltaic Specialists Conference}, pages = {2451-2454}, address = {Portland, OR, USA}, abstract = {Passivating junctions, like hole-collecting p-polycrystalline silicon/SiOx/crystalline silicon junctions, need a thermal activation to activate their excellent passivation and contact properties. Here, the diffusion of boron from the highly doped poly-Si layer into the Si is often considered to compromise the passivation quality. In contrast we show that at least a slight diffusion of boron into the crystalline silicon is present for optimized annealing conditions. We achieve low emitter saturation current densities of 11 fA/cm2 for in situ p+ doped polysilicon deposited by low pressure chemical vapor deposition. Furthermore, we show that the polysilicon layer and the in-diffused region within the substrate are electrically connected.}, keywords = {Annealing, boron, diffusion, junction formation, Junctions, low pressure chemical vapor deposition, passivating contacts, Resistance, Scanning electron microscopy, silicon, Substrates, Temperature measurement}, pubstate = {published}, tppubtype = {inproceedings} } Passivating junctions, like hole-collecting p-polycrystalline silicon/SiOx/crystalline silicon junctions, need a thermal activation to activate their excellent passivation and contact properties. Here, the diffusion of boron from the highly doped poly-Si layer into the Si is often considered to compromise the passivation quality. In contrast we show that at least a slight diffusion of boron into the crystalline silicon is present for optimized annealing conditions. We achieve low emitter saturation current densities of 11 fA/cm2 for in situ p+ doped polysilicon deposited by low pressure chemical vapor deposition. Furthermore, we show that the polysilicon layer and the in-diffused region within the substrate are electrically connected.
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D. Tetzlaff, J. Krügener, Y. Larionova, S. Reiter, M. Turcu, R. Peibst, U. Höhne, J. -D. Kähler, and T. Wietler Evolution of oxide disruptions: The (w)hole story about passivating contacts Inproceedings IEEE (Hrsg.): 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC), 0221-0224, Portland, OR, USA, (2016), ISBN: 978-1-5090-2725-5. Abstract | Links | BibTeX | Schlagwörter: Annealing, junction formation, Junctions, Microscopy, passivating contacts, Photovoltaic cells, Photovoltaic systems, pinholes, polysilicon, silicon, silicon oxide @inproceedings{Tetzlaff2016,
title = {Evolution of oxide disruptions: The (w)hole story about passivating contacts}, author = {D Tetzlaff and J Krügener and Y Larionova and S Reiter and M Turcu and R Peibst and U Höhne and J -D Kähler and T Wietler}, editor = {IEEE}, doi = {10.1109/PVSC.2016.7749582}, isbn = {978-1-5090-2725-5}, year = {2016}, date = {2016-06-01}, booktitle = {2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC)}, journal = {Proceedings of the 43rd IEEE Photovoltaic Specialists Conference}, pages = {0221-0224}, address = {Portland, OR, USA}, abstract = {Different models exist describing the current transport in polycrystalline Si/SiOx/crystalline Si junctions. Besides tunneling through thin oxides, transport through pinholes is discussed. We investigate the influence of annealing temperature on the structural properties of polycrystalline Si/SiOx/crystalline Si interfaces and analyze the formation and evolution of holes by high resolution transmission electron microscopy in comparison to electrical results. We prove the existence of pinholes in samples with good electrical properties in agreement with the pinhole model.}, keywords = {Annealing, junction formation, Junctions, Microscopy, passivating contacts, Photovoltaic cells, Photovoltaic systems, pinholes, polysilicon, silicon, silicon oxide}, pubstate = {published}, tppubtype = {inproceedings} } Different models exist describing the current transport in polycrystalline Si/SiOx/crystalline Si junctions. Besides tunneling through thin oxides, transport through pinholes is discussed. We investigate the influence of annealing temperature on the structural properties of polycrystalline Si/SiOx/crystalline Si interfaces and analyze the formation and evolution of holes by high resolution transmission electron microscopy in comparison to electrical results. We prove the existence of pinholes in samples with good electrical properties in agreement with the pinhole model.
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2015 |
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U. Römer, R. Peibst, T. Ohrdes, B. Lim, J. Krügener, T. Wietler, and R. Brendel Ion implantation for poly-Si passivated back-junction back-contacted solar cells Artikel IEEE Journal of Photovoltaics 5 (2), 507-514, (2015). Links | BibTeX | Schlagwörter: Back contact solar cells, boron, Carrier Selective Contacts, Doping, Implants, Ion implantation, Junctions, Photovoltaic cells, silicon, solar energy @article{Römer2015,
title = {Ion implantation for poly-Si passivated back-junction back-contacted solar cells}, author = {U Römer and R Peibst and T Ohrdes and B Lim and J Krügener and T Wietler and R Brendel}, doi = {10.1109/JPHOTOV.2014.2382975}, year = {2015}, date = {2015-03-01}, journal = {IEEE Journal of Photovoltaics}, volume = {5}, number = {2}, pages = {507-514}, keywords = {Back contact solar cells, boron, Carrier Selective Contacts, Doping, Implants, Ion implantation, Junctions, Photovoltaic cells, silicon, solar energy}, pubstate = {published}, tppubtype = {article} } |
2014 |
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R. Peibst, U. Römer, Y. Larionova, H. Schulte-Huxel, T. Ohrdes, M. Häberle, B. Lim, J. Krügener, D. Stichtenoth, T. Wütherich, C. Schöllhorn, J. Graff, and R. Brendel Building blocks for back-junction back-contacted cells and modules with ion-implanted poly-Si junctions Inproceedings IEEE (Hrsg.): 2014 IEEE 40th Photovoltaic Specialist Conference (PVSC) , 0852-0856, Denver, CO, USA, (2014), ISBN: 978-1-4799-4398-2. Links | BibTeX | Schlagwörter: Back contact solar cells, Ion implantation, Junctions, metallization, module-level interconnection, passivation, Photovoltaic cell, Photovoltaic cells, Radiative recombination, silicon, solar energy @inproceedings{Peibst2014,
title = {Building blocks for back-junction back-contacted cells and modules with ion-implanted poly-Si junctions}, author = {R Peibst and U Römer and Y Larionova and H Schulte-Huxel and T Ohrdes and M Häberle and B Lim and J Krügener and D Stichtenoth and T Wütherich and C Schöllhorn and J Graff and R Brendel}, editor = {IEEE}, doi = {10.1109/PVSC.2014.6925049}, isbn = {978-1-4799-4398-2}, year = {2014}, date = {2014-06-08}, booktitle = {2014 IEEE 40th Photovoltaic Specialist Conference (PVSC) }, journal = {Proceedings of the 40th IEEE Photovoltaic Specialists Conference}, pages = {0852-0856}, address = {Denver, CO, USA}, keywords = {Back contact solar cells, Ion implantation, Junctions, metallization, module-level interconnection, passivation, Photovoltaic cell, Photovoltaic cells, Radiative recombination, silicon, solar energy}, pubstate = {published}, tppubtype = {inproceedings} } |
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R. Peibst, U. Römer, K. R. Hofmann, B. Lim, T. F. Wietler, J. Krügener, N. -P. Harder, and R. Brendel IEEE Journal of Photovoltaics 4 (3), 841-850, (2014). Links | BibTeX | Schlagwörter: Bipolar transistors (BJTs), charge carriers, Doping, Junctions, Photovoltaic cells, Resistance, Semiconductor process modeling, silicon, Tunneling @article{Peibst2014b,
title = {A simple model describing the symmetric IV characteristics of p polycrystalline Si/n monocrystalline Si and n polycrystalline Si/p monocrystalline Si junctions}, author = {R Peibst and U Römer and K R Hofmann and B Lim and T F Wietler and J Krügener and N -P Harder and R Brendel}, doi = {10.1109/JPHOTOV.2014.2310740}, year = {2014}, date = {2014-05-01}, journal = {IEEE Journal of Photovoltaics}, volume = {4}, number = {3}, pages = {841-850}, keywords = {Bipolar transistors (BJTs), charge carriers, Doping, Junctions, Photovoltaic cells, Resistance, Semiconductor process modeling, silicon, Tunneling}, pubstate = {published}, tppubtype = {article} } |
2010 |
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D. Hinken, A. Milsted, R. Bock, B. Fischer, K. Bothe, M. Schutze, J. Isenberg, A. Schulze, and M. Wagner Determination of the Base-Dopant Concentration of Large-Area Crystalline Silicon Solar Cells Artikel IEEE Transactions on Electron Devices 57 (11), 2831-2837, (2010), ISSN: 0018-9383. Links | BibTeX | Schlagwörter: Capacitance, Capacitance–voltage characteristics, Current measurement, Junctions, Photovoltaic cells, silicon, Surface texture, Surface treatment @article{Hinken2010,
title = {Determination of the Base-Dopant Concentration of Large-Area Crystalline Silicon Solar Cells}, author = {D Hinken and A Milsted and R Bock and B Fischer and K Bothe and M Schutze and J Isenberg and A Schulze and M Wagner}, doi = {10.1109/TED.2010.2064777}, issn = {0018-9383}, year = {2010}, date = {2010-11-01}, journal = {IEEE Transactions on Electron Devices}, volume = {57}, number = {11}, pages = {2831-2837}, keywords = {Capacitance, Capacitance–voltage characteristics, Current measurement, Junctions, Photovoltaic cells, silicon, Surface texture, Surface treatment}, pubstate = {published}, tppubtype = {article} } |