1.
C Kranz; B Wolpensinger; R Brendel; T Dullweber
Analysis of local aluminum rear contacts of bifacial PERC+ solar cells Artikel
In: IEEE Journal of Photovoltaics, Bd. 6, Nr. 4, S. 830, 2016.
@article{Kranz2016b,
title = {Analysis of local aluminum rear contacts of bifacial PERC+ solar cells},
author = {C Kranz and B Wolpensinger and R Brendel and T Dullweber},
doi = {10.1109/JPHOTOV.2016.2551465},
year = {2016},
date = {2016-07-01},
journal = {IEEE Journal of Photovoltaics},
volume = {6},
number = {4},
pages = {830},
abstract = {A recently published industrial passivated emitter rear contact (PERC) solar cell concept called PERC+ enables bifacial applications by printing an aluminum (Al) finger grid instead of the full-area Al layer aligned to the laser contact openings on the rear side. We demonstrate that the rear contacts of these PERC+ solar cells exhibit back-surface field (BSF) depths of around 6 μm over a large range of contact linewidths, whereas PERC cells with full-area Al rear layer show a reduction of the Al-BSF depths for narrower contact lines. Using an existing analytical model for the local contact formation, we show that the measured Al-BSF depths are well described solely by the different volume of Al paste printed on the rear side. Consequently, the open-circuit voltage of PERC+ solar cells improves by up to 5 mV when reducing the contact linewidth only. In contrast, for PERC cells with full-area Al layer, the Voc slightly decreases with narrower contact linewidths due to the thinner Al-BSF depths. We observe a strongly reduced number of voids in the Al-Si eutectic layer for PERC+ cells, compared with PERC. As physical root cause for void formation, we propose the minimization of surface energy of the Al-Si melt.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A recently published industrial passivated emitter rear contact (PERC) solar cell concept called PERC+ enables bifacial applications by printing an aluminum (Al) finger grid instead of the full-area Al layer aligned to the laser contact openings on the rear side. We demonstrate that the rear contacts of these PERC+ solar cells exhibit back-surface field (BSF) depths of around 6 μm over a large range of contact linewidths, whereas PERC cells with full-area Al rear layer show a reduction of the Al-BSF depths for narrower contact lines. Using an existing analytical model for the local contact formation, we show that the measured Al-BSF depths are well described solely by the different volume of Al paste printed on the rear side. Consequently, the open-circuit voltage of PERC+ solar cells improves by up to 5 mV when reducing the contact linewidth only. In contrast, for PERC cells with full-area Al layer, the Voc slightly decreases with narrower contact linewidths due to the thinner Al-BSF depths. We observe a strongly reduced number of voids in the Al-Si eutectic layer for PERC+ cells, compared with PERC. As physical root cause for void formation, we propose the minimization of surface energy of the Al-Si melt.
2.
Y Chen; P P Altermatt; J Dong; S Zhang; J Liu; D Chen; W Deng; Y Jiang; B Liu; Wenming Xiao; H Zhu; H Chen; Haijun Jiao; X Pan; M Zhong; D Wang; J Sheng; Y Zhang; H Shen; Z Feng; P J Verlinden
Al-alloyed local contacts for industrial PERC cells by local printing Proceedings Article
In: 2014 IEEE 40th Photovoltaic Specialist Conference (PVSC), S. 3322-3325, 2014, ISSN: 0160-8371.
@inproceedings{Chen2014b,
title = {Al-alloyed local contacts for industrial PERC cells by local printing},
author = {Y Chen and P P Altermatt and J Dong and S Zhang and J Liu and D Chen and W Deng and Y Jiang and B Liu and Wenming Xiao and H Zhu and H Chen and Haijun Jiao and X Pan and M Zhong and D Wang and J Sheng and Y Zhang and H Shen and Z Feng and P J Verlinden},
doi = {10.1109/PVSC.2014.6925645},
issn = {0160-8371},
year = {2014},
date = {2014-06-01},
booktitle = {2014 IEEE 40th Photovoltaic Specialist Conference (PVSC)},
pages = {3322-3325},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}