1.
B Min; J Krügener; M Müller; K Bothe; R Brendel
In: Energy Procedia, Bd. 124, Nr. Supplement C, S. 126-130, 2017, ISSN: 1876-6102, (7th International Conference on Silicon Photovoltaics, SiliconPV 2017, 3-5 April 2017, Freiburg, Germany).
@article{Min2017d,
title = {Fundamental consideration of junction formation strategies for phosphorus-doped emitters with J0e < 10 fA/cm2},
author = {B Min and J Krügener and M Müller and K Bothe and R Brendel},
doi = {10.1016/j.egypro.2017.09.323},
issn = {1876-6102},
year = {2017},
date = {2017-09-21},
journal = {Energy Procedia},
volume = {124},
number = {Supplement C},
pages = {126-130},
abstract = {This work shows the potential of further optimization of phosphorus-doped emitters in p-type silicon solar cells. We investigate the impact of different combinations of phosphorus doping profiles and surface passivation qualities on the saturation current density J0e by considering boundary conditions based on published experimental data. Our simulation study shows that there are two possible ways to achieve J0e values below 10 fA/cm2. One is the reduction of the electrically active phosphorus concentration nsurf at the surface beneath 2×10^19 cm−3 and simultaneously reducing the surface recombination velocity Sp to below 103 cm/s. The other contrarily increases nsurf to values of up to 1×10^21 cm−3 while ensuring full activation of all phosphorus dopants. In the latter case, J0e values below 10 fA/cm2 seem possible, even for Sp = 10^7 cm/s which is equal to the thermal velocity.},
note = {7th International Conference on Silicon Photovoltaics, SiliconPV 2017, 3-5 April 2017, Freiburg, Germany},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This work shows the potential of further optimization of phosphorus-doped emitters in p-type silicon solar cells. We investigate the impact of different combinations of phosphorus doping profiles and surface passivation qualities on the saturation current density J0e by considering boundary conditions based on published experimental data. Our simulation study shows that there are two possible ways to achieve J0e values below 10 fA/cm2. One is the reduction of the electrically active phosphorus concentration nsurf at the surface beneath 2×10^19 cm−3 and simultaneously reducing the surface recombination velocity Sp to below 103 cm/s. The other contrarily increases nsurf to values of up to 1×10^21 cm−3 while ensuring full activation of all phosphorus dopants. In the latter case, J0e values below 10 fA/cm2 seem possible, even for Sp = 10^7 cm/s which is equal to the thermal velocity.
2.
D Tetzlaff; J Krügener; Y Larionova; S Reiter; M Turcu; R Peibst; U Höhne; J -D Kähler; T Wietler
Evolution of oxide disruptions: The (w)hole story about passivating contacts Proceedings Article
In: IEEE, (Hrsg.): 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC), S. 0221-0224, Portland, OR, USA, 2016, ISBN: 978-1-5090-2725-5.
@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 = {},
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.
3.
J Krügener; Y Larionova; B Wolpensinger; D Tetzlaff; S Reiter; M Turcu; R Peibst; J -D Kähler; T Wietler
Dopant diffusion from p+-poly-Si into c-Si during thermal annealing Proceedings Article
In: IEEE, (Hrsg.): 2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC), S. 2451-2454, Portland, OR, USA, 2016, ISBN: 978-1-5090-2725-5.
@inproceedings{Krügener2016bc,
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 = {},
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.