5 Crystalline Silicon Solar Cells: Homojunction Cells
137
such a cell structure is quite complex. An alternative is to apply the IBC concept
to heterojunction cells (see Chap. 7). Here, the p-region is next to the n-region and
the emitter can be enlarged compared to the cell concept described in the present
Section. Since the thin p- and n-doped amorphous layers have very low conductivity,
they can be placed immediately adjacent to each other. HJT-IBC cells have excellent
passivation properties due to the amorphous layer. With such a structure, Kaneka
Inc. has achieved 26.7% cell designated-area
41 efficiency on 79 cm
2 and 26.6%
designated-area efficiency on a larger cell of 180 cm
2 [15].
With passivated “polycrystalline silicon on oxides” (POLO) contacts [16], the
ISFH institute (Institut für Solarenergieforschung in Hameln) achieved in 2018
a designated-area cell efficiency of 26.1%, with an open circuit voltage V oc of
726.6 mV, a short-circuit current density I sc of 42.6 mA/cm
2 , with a fill factor FF of
84% on a 4 cm
2 p-type Wafer and an IBC structure. The polycrystalline p-regions
and the polycrystalline n-regions lie side by side and are mutually isolated by an
intrinsic polycrystalline Si(i)-layer.
References
1. H. Jakob, Reinstsilicium – Werkstoff des Computerzeitalters (Praxis der Naturwissenschaften
Chemie, Aulius Verlag Köln Deubner & CO KG, 1988)
2. P. Capper, Bulk Crystal Growth in Electronic, Optical and Optoelectronics Materials (Wiley,
The Atrium, Southern Gate, 2005)
3. J.D. Murphy, M. Al-Amin, K. Bothe, M. Olmo, V.V. Voronkov, R.J. Falster; The effect of oxide
precipitates on minority carrier lifetime in n-type silicon, published online 7 December 2015.
J. Appl. Phys. 118, 215706 (2015)
4. A. Hess, P. Krenckel, T. Trötschler, T. Feherenbach, S. Riepe, Development of high performance
multicrystalline silicon with controlled seeding (Fraunhiofer Institut for Solar Energy Systems
ISE; publica.fraunhofer.de/dokumente/N-521450.html, 2018)
5. G. Stokkan, A. Song, B. Rynigen, Investigation of the Grain Boundary Character and Dislocation Density of Different Types of High Performance Multicrystalline Silicon (Crystal Journal
Published by MDPI, 2018)
6. A. Hein, Einflüsse von Verunreinigungen im Silicium und in der Ätzlösung auf das anisotrope
Ätzen von Silicium in wäßrigen KOH-Ätzlösungen. Dissertation, TU-Berlin 2000, Berlin 2000
7. A. Luque, S. Hegedus, Handbook of Photovoltaic Science and Engineering. ISBN 13:978-0471-49196-5(H/B) (Wiley, 2005)
8. S. Gatz, et.al. Analysis of local Al-doped back surface fields for high efficiency screen-printed
solar cells. Energy Procedia S. 318–323 (2011). https://doi.org/10.1016/j.egypro.2011.06.143
9. D.A. Neamen, Semiconductor Physics and Devices, Basis Principles (McGraw Hill, 2003)
10. P. Saint-Cast et al., A review of PECVD aluminium oxide for surface, in 27th PVSEC, 2012,
European Photovoltaic Solar Energy Conference and Exhibition (Frankfurt, 2012)
11. E. Urrejola Davanzo, Aluminium-silicon contact formation through narrow dielectric openings,
Ph.D. thesis, at University Konstanz, Konstanz, 2012
41 The “designated area” is the area of the wafer on which the active solar cell is located. Often
a large wafer is used for research cells, but the solar cell is only located on a small area of the
entire wafer—the “designated area”—The term “designated area” is only used in Research and
Development.
137
such a cell structure is quite complex. An alternative is to apply the IBC concept
to heterojunction cells (see Chap. 7). Here, the p-region is next to the n-region and
the emitter can be enlarged compared to the cell concept described in the present
Section. Since the thin p- and n-doped amorphous layers have very low conductivity,
they can be placed immediately adjacent to each other. HJT-IBC cells have excellent
passivation properties due to the amorphous layer. With such a structure, Kaneka
Inc. has achieved 26.7% cell designated-area
41 efficiency on 79 cm
2 and 26.6%
designated-area efficiency on a larger cell of 180 cm
2 [15].
With passivated “polycrystalline silicon on oxides” (POLO) contacts [16], the
ISFH institute (Institut für Solarenergieforschung in Hameln) achieved in 2018
a designated-area cell efficiency of 26.1%, with an open circuit voltage V oc of
726.6 mV, a short-circuit current density I sc of 42.6 mA/cm
2 , with a fill factor FF of
84% on a 4 cm
2 p-type Wafer and an IBC structure. The polycrystalline p-regions
and the polycrystalline n-regions lie side by side and are mutually isolated by an
intrinsic polycrystalline Si(i)-layer.
References
1. H. Jakob, Reinstsilicium – Werkstoff des Computerzeitalters (Praxis der Naturwissenschaften
Chemie, Aulius Verlag Köln Deubner & CO KG, 1988)
2. P. Capper, Bulk Crystal Growth in Electronic, Optical and Optoelectronics Materials (Wiley,
The Atrium, Southern Gate, 2005)
3. J.D. Murphy, M. Al-Amin, K. Bothe, M. Olmo, V.V. Voronkov, R.J. Falster; The effect of oxide
precipitates on minority carrier lifetime in n-type silicon, published online 7 December 2015.
J. Appl. Phys. 118, 215706 (2015)
4. A. Hess, P. Krenckel, T. Trötschler, T. Feherenbach, S. Riepe, Development of high performance
multicrystalline silicon with controlled seeding (Fraunhiofer Institut for Solar Energy Systems
ISE; publica.fraunhofer.de/dokumente/N-521450.html, 2018)
5. G. Stokkan, A. Song, B. Rynigen, Investigation of the Grain Boundary Character and Dislocation Density of Different Types of High Performance Multicrystalline Silicon (Crystal Journal
Published by MDPI, 2018)
6. A. Hein, Einflüsse von Verunreinigungen im Silicium und in der Ätzlösung auf das anisotrope
Ätzen von Silicium in wäßrigen KOH-Ätzlösungen. Dissertation, TU-Berlin 2000, Berlin 2000
7. A. Luque, S. Hegedus, Handbook of Photovoltaic Science and Engineering. ISBN 13:978-0471-49196-5(H/B) (Wiley, 2005)
8. S. Gatz, et.al. Analysis of local Al-doped back surface fields for high efficiency screen-printed
solar cells. Energy Procedia S. 318–323 (2011). https://doi.org/10.1016/j.egypro.2011.06.143
9. D.A. Neamen, Semiconductor Physics and Devices, Basis Principles (McGraw Hill, 2003)
10. P. Saint-Cast et al., A review of PECVD aluminium oxide for surface, in 27th PVSEC, 2012,
European Photovoltaic Solar Energy Conference and Exhibition (Frankfurt, 2012)
11. E. Urrejola Davanzo, Aluminium-silicon contact formation through narrow dielectric openings,
Ph.D. thesis, at University Konstanz, Konstanz, 2012
41 The “designated area” is the area of the wafer on which the active solar cell is located. Often
a large wafer is used for research cells, but the solar cell is only located on a small area of the
entire wafer—the “designated area”—The term “designated area” is only used in Research and
Development.