1.
R C Whitehead; K T VanSant; E L Warren; J Buencuerpo; M Rienäcker; R Peibst; J F Geisz; A C Tamboli
In: Applied Physics Letters, Bd. 118, Nr. 18, S. 183902, 2021.
@article{Whitehead2021,
title = {Optimization of four terminal rear heterojunction GaAs on Si interdigitated back contact tandem solar cells},
author = {R C Whitehead and K T VanSant and E L Warren and J Buencuerpo and M Rienäcker and R Peibst and J F Geisz and A C Tamboli},
doi = {10.1063/5.0049097},
year = {2021},
date = {2021-05-03},
journal = {Applied Physics Letters},
volume = {118},
number = {18},
pages = {183902},
abstract = {High-efficiency, four-terminal tandem solar cells composed of thin GaAs films mechanically stacked onto interdigitated back contact silicon solar cells with a glass interlayer are demonstrated. The optimal thickness of the absorber layer of a rear heterojunction GaAs subcell for use in four terminal tandem solar cells was studied. GaAs top cells with absorber layer thicknesses of 1.5, 1.9, 2.3, 2.8, and 3.5 μm were fabricated on glass and mechanically stacked onto interdigitated back-contact Si bottom cells. All tandem cells were found to have efficiencies above 30% under the AM1.5 G spectrum demonstrating a relatively weak sensitivity to thickness in the four-terminal configuration. We found the 2.8 μm absorber layer cell to have the highest top cell and tandem cell efficiency at 26.38% and 32.57%, respectively. Optical modeling with transfer matrix method for the planar top cell and Lambertian light trapping in the textured Si subcell, along with drift-diffusion Hovel equations, were used to show photon recycling enhancement to the effective diffusion length and VOC of the top cell as a result of the low-index glass interlayer.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
High-efficiency, four-terminal tandem solar cells composed of thin GaAs films mechanically stacked onto interdigitated back contact silicon solar cells with a glass interlayer are demonstrated. The optimal thickness of the absorber layer of a rear heterojunction GaAs subcell for use in four terminal tandem solar cells was studied. GaAs top cells with absorber layer thicknesses of 1.5, 1.9, 2.3, 2.8, and 3.5 μm were fabricated on glass and mechanically stacked onto interdigitated back-contact Si bottom cells. All tandem cells were found to have efficiencies above 30% under the AM1.5 G spectrum demonstrating a relatively weak sensitivity to thickness in the four-terminal configuration. We found the 2.8 μm absorber layer cell to have the highest top cell and tandem cell efficiency at 26.38% and 32.57%, respectively. Optical modeling with transfer matrix method for the planar top cell and Lambertian light trapping in the textured Si subcell, along with drift-diffusion Hovel equations, were used to show photon recycling enhancement to the effective diffusion length and VOC of the top cell as a result of the low-index glass interlayer.
2.
E L Warren; W E McMahon; M Rienäcker; K T VanSant; R C Whitehead; R Peibst; A C Tamboli
A Taxonomy for Three-Terminal Tandem Solar Cells Artikel
In: ACS Energy Letters, Bd. 5, Nr. 4, S. 1233-1242, 2020.
@article{Warren2020,
title = {A Taxonomy for Three-Terminal Tandem Solar Cells},
author = {E L Warren and W E McMahon and M Rienäcker and K T VanSant and R C Whitehead and R Peibst and A C Tamboli},
doi = {10.1021/acsenergylett.0c00068},
year = {2020},
date = {2020-04-01},
journal = {ACS Energy Letters},
volume = {5},
number = {4},
pages = {1233-1242},
abstract = {Tandem and multijunction solar cells offer the only demonstrated path to terrestrial 1-sun solar cell efficiency over 30%. Three-terminal tandem (3TT) solar cells can overcome some of the limitations of two-terminal and four-terminal tandem solar cell designs. However, the coupled nature of the cells adds a degree of complexity to the devices themselves and the ways that their performance can be measured and reported. While many different configurations of 3TT devices have been proposed, there is no standard taxonomy to discuss the device structure or loading topology. This Perspective proposes a taxonomy for 3TT solar cells to enable a common nomenclature for discussing these devices and their performance. It also provides a brief history of three-terminal devices in the literature and demonstrates that many different 3TT devices can work at efficiencies above 30% if properly designed.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Tandem and multijunction solar cells offer the only demonstrated path to terrestrial 1-sun solar cell efficiency over 30%. Three-terminal tandem (3TT) solar cells can overcome some of the limitations of two-terminal and four-terminal tandem solar cell designs. However, the coupled nature of the cells adds a degree of complexity to the devices themselves and the ways that their performance can be measured and reported. While many different configurations of 3TT devices have been proposed, there is no standard taxonomy to discuss the device structure or loading topology. This Perspective proposes a taxonomy for 3TT solar cells to enable a common nomenclature for discussing these devices and their performance. It also provides a brief history of three-terminal devices in the literature and demonstrates that many different 3TT devices can work at efficiencies above 30% if properly designed.
3.
R Peibst; M Rienäcker; B Min; C Klamt; R Niepelt; T F Wietler; T Dullweber; E Sauter; J Hübner; M Oestreich; R Brendel
In: IEEE Journal of Photovoltaics, Bd. 9, Nr. 1, S. 49-54, 2019, ISSN: 2156-3381.
@article{Peibst2019,
title = {From PERC to Tandem: POLO- and p+/n+ Poly-Si Tunneling Junction as Interface Between Bottom and Top Cell},
author = {R Peibst and M Rienäcker and B Min and C Klamt and R Niepelt and T F Wietler and T Dullweber and E Sauter and J Hübner and M Oestreich and R Brendel},
doi = {10.1109/JPHOTOV.2018.2876999},
issn = {2156-3381},
year = {2019},
date = {2019-01-01},
journal = {IEEE Journal of Photovoltaics},
volume = {9},
number = {1},
pages = {49-54},
abstract = {We present a novel cell concept that combines the tandem cell approach with the passivated emitter and rear cells (PERC) mainstream technology. As an interface between Si bottom and top cell, we utilize passivating n+-type polysilicon on oxide (POLO) contacts and a p+ poly-Si/n+ poly-Si tunneling junction. Our full area PERC+ Si bottom cells are fabricated within a typical industrial process sequence where the POCl$_3$diffusion and SiN$_textx$deposition are replaced by the POLO junction formation processes. The implied open-circuit voltage iV$_textoc$that is measured on these devices reaches up to 708 mV (684 mV) under 1 sun (under filtered spectrum to simulated top cell absorption). On sister cells with planar front side, the respective iV$_textoc$values are 718 mV (696 mV). In order to understand the device physics of our ultra-abrupt p+ poly-Si/n+ poly-Si tunneling junction, we determined the carrier lifetime in the poly-Si by time-resolved photoluminescence. The extracted lifetimes of 42–54 ps enter as input parameter for numerical Sentaurus Device simulations. These simulations reveal the importance of band-to-band and trap-assisted tunneling for a low tunneling junction resistivity of 2.95 mΩ·cm2. Experimentally, an upper limit for the combined junction resistance of the p+ poly-Si/n+ poly-Si/SiO$_textx$stack of 100 mΩ·cm2 is determined.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We present a novel cell concept that combines the tandem cell approach with the passivated emitter and rear cells (PERC) mainstream technology. As an interface between Si bottom and top cell, we utilize passivating n+-type polysilicon on oxide (POLO) contacts and a p+ poly-Si/n+ poly-Si tunneling junction. Our full area PERC+ Si bottom cells are fabricated within a typical industrial process sequence where the POCl$_3$diffusion and SiN$_textx$deposition are replaced by the POLO junction formation processes. The implied open-circuit voltage iV$_textoc$that is measured on these devices reaches up to 708 mV (684 mV) under 1 sun (under filtered spectrum to simulated top cell absorption). On sister cells with planar front side, the respective iV$_textoc$values are 718 mV (696 mV). In order to understand the device physics of our ultra-abrupt p+ poly-Si/n+ poly-Si tunneling junction, we determined the carrier lifetime in the poly-Si by time-resolved photoluminescence. The extracted lifetimes of 42–54 ps enter as input parameter for numerical Sentaurus Device simulations. These simulations reveal the importance of band-to-band and trap-assisted tunneling for a low tunneling junction resistivity of 2.95 mΩ·cm2. Experimentally, an upper limit for the combined junction resistance of the p+ poly-Si/n+ poly-Si/SiO$_textx$stack of 100 mΩ·cm2 is determined.
4.
K VanSant; J Simon; M Schnabel; J Geisz; K Schulte; A Ptak; M Young; D Guiling; W Olavarria; M Rienaecker; H Schulte-Huxel; R Niepelt; S Kajari-Schroeder; R Brendel; R Peibst; A Tamboli
HVPE-Grown GaAs//Si Tandem Device Performance Proceedings Article
In: IEEE, (Hrsg.): 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC 34th EU PVSEC), S. 2776-2778, Waikoloa Village, HI, USA, 2018, ISSN: 0160-8371.
@inproceedings{VanSant2018,
title = {HVPE-Grown GaAs//Si Tandem Device Performance},
author = {K VanSant and J Simon and M Schnabel and J Geisz and K Schulte and A Ptak and M Young and D Guiling and W Olavarria and M Rienaecker and H Schulte-Huxel and R Niepelt and S Kajari-Schroeder and R Brendel and R Peibst and A Tamboli},
editor = {IEEE},
doi = {10.1109/PVSC.2018.8547889},
issn = {0160-8371},
year = {2018},
date = {2018-06-01},
booktitle = {2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC 34th EU PVSEC)},
pages = {2776-2778},
address = {Waikoloa Village, HI, USA},
abstract = {The performance of III-V//Si tandem devices has successfully exceeded the theoretical efficiency limit of single junction Si devices (29.4%) yet the costs associated with these high-efficiency tandem devices are still too high to compete with today's conventional Si solar cells. Recent cost modeling efforts suggest that hydride vapor phase epitaxy (HVPE) could be adopted as an alternative growth technique to metal-organic chemical vapor deposition (MOCVD) because the costs of HVPE are substantially lower and the performance of devices fabricated from HVPE materials are continuously improving. This study reports on our first results of a HVPE-grown GaAs top cell mechanically stacked on a Si bottom cell.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
The performance of III-V//Si tandem devices has successfully exceeded the theoretical efficiency limit of single junction Si devices (29.4%) yet the costs associated with these high-efficiency tandem devices are still too high to compete with today's conventional Si solar cells. Recent cost modeling efforts suggest that hydride vapor phase epitaxy (HVPE) could be adopted as an alternative growth technique to metal-organic chemical vapor deposition (MOCVD) because the costs of HVPE are substantially lower and the performance of devices fabricated from HVPE materials are continuously improving. This study reports on our first results of a HVPE-grown GaAs top cell mechanically stacked on a Si bottom cell.
5.
R Peibst; M Rienäcker; B Min; C Klamt; R Niepelt; T Wietler; T Dullweber; E Sauter; J Hïbner; M Oestreich; R Brendel
p+/n+ polysilicon-on-oxide tunneling junctions as an interface of p-type PERC cells for tandem applications Proceedings Article
In: IEEE, (Hrsg.): 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC 34th EU PVSEC), S. 2635-2637, Waikoloa Village, HI, USA, 2018, ISSN: 0160-8371.
@inproceedings{Peibst2018db,
title = {p+/n+ polysilicon-on-oxide tunneling junctions as an interface of p-type PERC cells for tandem applications},
author = {R Peibst and M Rienäcker and B Min and C Klamt and R Niepelt and T Wietler and T Dullweber and E Sauter and J Hïbner and M Oestreich and R Brendel},
editor = {IEEE},
doi = {10.1109/PVSC.2018.8548032},
issn = {0160-8371},
year = {2018},
date = {2018-06-01},
booktitle = {2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC 34th EU PVSEC)},
pages = {2635-2637},
address = {Waikoloa Village, HI, USA},
abstract = {We present a novel cell concept that combines the tandem cell approach with the PERC mainstream technology. As an interface between Si bottom and top cell, we utilize passivating n+-type polysilicon on oxide (POLO) contacts and a p+ poly-Si / n+poly-Si tunneling junction. Our full area PERC+Si bottom cells are fabricated within a typical industrial process sequence where the POCl3-diffusion and SiNxdeposition are replaced by the POLO junction formation processes. The implied open circuit voltage iVocmeasured on these devices reaches up to 708 mV (684 mV) under 1 sun (under filtered spectrum), respectively.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
We present a novel cell concept that combines the tandem cell approach with the PERC mainstream technology. As an interface between Si bottom and top cell, we utilize passivating n+-type polysilicon on oxide (POLO) contacts and a p+ poly-Si / n+poly-Si tunneling junction. Our full area PERC+Si bottom cells are fabricated within a typical industrial process sequence where the POCl3-diffusion and SiNxdeposition are replaced by the POLO junction formation processes. The implied open circuit voltage iVocmeasured on these devices reaches up to 708 mV (684 mV) under 1 sun (under filtered spectrum), respectively.
6.
U Römer; R Peibst; T Ohrdes; B Lim; J Krügener; T Wietler; R Brendel
Ion implantation for poly-Si passivated back-junction back-contacted solar cells Artikel
In: IEEE Journal of Photovoltaics, Bd. 5, Nr. 2, S. 507-514, 2015.
@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 = {},
pubstate = {published},
tppubtype = {article}
}
7.
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; R Brendel
Building blocks for back-junction back-contacted cells and modules with ion-implanted poly-Si junctions Proceedings Article
In: IEEE, (Hrsg.): 2014 IEEE 40th Photovoltaic Specialist Conference (PVSC), S. 0852-0856, Denver, CO, USA, 2014, ISBN: 978-1-4799-4398-2.
@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 = {},
pubstate = {published},
tppubtype = {inproceedings}
}
8.
U Römer; R Peibst; T Ohrdes; Y Larionova; N -P Harder; R Brendel; A Grohe; D Stichtenoth; T Wütherich; C Schöllhorn; H -J Krokoszinski; J Graff
Counterdoping with Patterned Ion Implantation Proceedings Article
In: IEEE, (Hrsg.): 2013 IEEE 39th Photovoltaic Specialists Conference (PVSC), S. 1280-1284, Tampa, FL, USA, 2013, ISBN: 978-1-4799-3299-3.
@inproceedings{Römer2013,
title = {Counterdoping with Patterned Ion Implantation},
author = {U Römer and R Peibst and T Ohrdes and Y Larionova and N -P Harder and R Brendel and A Grohe and D Stichtenoth and T Wütherich and C Schöllhorn and H -J Krokoszinski and J Graff},
editor = {IEEE},
doi = {10.1109/PVSC.2013.6744375},
isbn = {978-1-4799-3299-3},
year = {2013},
date = {2013-06-16},
booktitle = {2013 IEEE 39th Photovoltaic Specialists Conference (PVSC)},
journal = {Proceedings of the 39th IEEE Photovoltaic Specialists Conference},
pages = {1280-1284},
address = {Tampa, FL, USA},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
9.
J Glembin; D Eggert; G Rockendorf; J Scheuren
Evaporation in Solar Thermal Collectors During Operation - Reasons and Effects of Partial Stagnation Artikel
In: Journal of Solar Energy Engineering, Bd. 133, Nr. 4, S. 041003, 2011.
@article{Glembin2011,
title = {Evaporation in Solar Thermal Collectors During Operation - Reasons and Effects of Partial Stagnation},
author = {J Glembin and D Eggert and G Rockendorf and J Scheuren},
doi = {10.1115/1.4004384},
year = {2011},
date = {2011-09-01},
journal = {Journal of Solar Energy Engineering},
volume = {133},
number = {4},
pages = {041003},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
10.
F Kiefer; C Ulzhofer; T Brendemuhl; N P Harder; R Brendel; V Mertens; S Bordihn; C Peters; J W Muller
High Efficiency N-Type Emitter-Wrap-Through Silicon Solar Cells Artikel
In: IEEE Journal of Photovoltaics, Bd. 1, Nr. 1, S. 49-53, 2011, ISSN: 2156-3381.
@article{Kiefer2011b,
title = {High Efficiency N-Type Emitter-Wrap-Through Silicon Solar Cells},
author = {F Kiefer and C Ulzhofer and T Brendemuhl and N P Harder and R Brendel and V Mertens and S Bordihn and C Peters and J W Muller},
doi = {10.1109/JPHOTOV.2011.2164953},
issn = {2156-3381},
year = {2011},
date = {2011-07-01},
journal = {IEEE Journal of Photovoltaics},
volume = {1},
number = {1},
pages = {49-53},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
11.
S Gatz; T Dullweber; R Brendel
Contact resistance of local rear side contacts of screen-printed silicon PERC solar cells with efficiencies up to 19.4% Proceedings Article
In: IEEE, (Hrsg.): 2011 37th IEEE Photovoltaic Specialists Conference, S. 003658, Seattle, WA, USA, 2011, ISSN: 0160-8371.
@inproceedings{Gatz2011cb,
title = {Contact resistance of local rear side contacts of screen-printed silicon PERC solar cells with efficiencies up to 19.4%},
author = {S Gatz and T Dullweber and R Brendel},
editor = {IEEE},
doi = {10.1109/PVSC.2011.6185943},
issn = {0160-8371},
year = {2011},
date = {2011-06-01},
booktitle = {2011 37th IEEE Photovoltaic Specialists Conference},
pages = {003658},
address = {Seattle, WA, USA},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}