Details
| Original language | English |
|---|---|
| Article number | 7296574 |
| Pages (from-to) | 1606-1612 |
| Number of pages | 7 |
| Journal | IEEE Journal of Photovoltaics |
| Volume | 5 |
| Issue number | 6 |
| Publication status | Published - 12 Oct 2015 |
Abstract
Laser welding of thin Al layers offers a silver-free and highly flexible option for the interconnection of Al-metallized solar cells. Welding requires the melting of the Al layers in order to form a reliable electrical and mechanical contact. Here, we investigate the process driving the melt front of the aluminum, which is attached to a transparent substrate, toward the interface between the two Al layers. In experiments, we observe two different mechanisms depending on the thickness of the irradiated layer. In the case of Al layers thinner than 5 μm, a melt-through of the Al-layer is observed, whereas for thicker layers, thermal expansion causes a breakage of the surface and ejection of molten Al, which enables the contact formation. Using simulations that are based on the finite-element method, we instigate both mechanisms. The simulation results match the experimental observations within the measurement uncertainty. In case of thin layers, the simulation shows that the process is limited by thermal diffusion. For thicker Al layers, the onset of melting on the irradiated side initiates the breakage of the surface and the ejection of the aluminum.
Keywords
- Al metallization, cell interconnection, finite-element method (FEM) simulations, laser processing, module integration
ASJC Scopus subject areas
- Materials Science(all)
- Electronic, Optical and Magnetic Materials
- Physics and Astronomy(all)
- Condensed Matter Physics
- Engineering(all)
- Electrical and Electronic Engineering
Cite this
- Standard
- Harvard
- Apa
- Vancouver
- BibTeX
- RIS
In: IEEE Journal of Photovoltaics, Vol. 5, No. 6, 7296574, 12.10.2015, p. 1606-1612.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Analysis of Thermal Processes Driving Laser Welding of Aluminum Deposited on Glass Substrates for Module Interconnection of Silicon Solar Cells
AU - Schulte-Huxel, Henning
AU - Kajari-Schröder, Sarah
AU - Brendel, Rolf
PY - 2015/10/12
Y1 - 2015/10/12
N2 - Laser welding of thin Al layers offers a silver-free and highly flexible option for the interconnection of Al-metallized solar cells. Welding requires the melting of the Al layers in order to form a reliable electrical and mechanical contact. Here, we investigate the process driving the melt front of the aluminum, which is attached to a transparent substrate, toward the interface between the two Al layers. In experiments, we observe two different mechanisms depending on the thickness of the irradiated layer. In the case of Al layers thinner than 5 μm, a melt-through of the Al-layer is observed, whereas for thicker layers, thermal expansion causes a breakage of the surface and ejection of molten Al, which enables the contact formation. Using simulations that are based on the finite-element method, we instigate both mechanisms. The simulation results match the experimental observations within the measurement uncertainty. In case of thin layers, the simulation shows that the process is limited by thermal diffusion. For thicker Al layers, the onset of melting on the irradiated side initiates the breakage of the surface and the ejection of the aluminum.
AB - Laser welding of thin Al layers offers a silver-free and highly flexible option for the interconnection of Al-metallized solar cells. Welding requires the melting of the Al layers in order to form a reliable electrical and mechanical contact. Here, we investigate the process driving the melt front of the aluminum, which is attached to a transparent substrate, toward the interface between the two Al layers. In experiments, we observe two different mechanisms depending on the thickness of the irradiated layer. In the case of Al layers thinner than 5 μm, a melt-through of the Al-layer is observed, whereas for thicker layers, thermal expansion causes a breakage of the surface and ejection of molten Al, which enables the contact formation. Using simulations that are based on the finite-element method, we instigate both mechanisms. The simulation results match the experimental observations within the measurement uncertainty. In case of thin layers, the simulation shows that the process is limited by thermal diffusion. For thicker Al layers, the onset of melting on the irradiated side initiates the breakage of the surface and the ejection of the aluminum.
KW - Al metallization
KW - cell interconnection
KW - finite-element method (FEM) simulations
KW - laser processing
KW - module integration
UR - http://www.scopus.com/inward/record.url?scp=84947028455&partnerID=8YFLogxK
U2 - 10.1109/JPHOTOV.2015.2478027
DO - 10.1109/JPHOTOV.2015.2478027
M3 - Article
AN - SCOPUS:84947028455
VL - 5
SP - 1606
EP - 1612
JO - IEEE Journal of Photovoltaics
JF - IEEE Journal of Photovoltaics
SN - 2156-3381
IS - 6
M1 - 7296574
ER -