Morphological Characteristics and Printing Mechanisms of Grid Lines by Laser-Induced Forward Transfer
Abstract
:1. Introduction
2. Experimental Setup and Materials
3. Results and Discussion
3.1. Width, Height and Aspect-Ratio of Formed Lines
3.2. Morphological Characteristics of Formed Lines
3.3. Dynamics Process of Silver Paste Transfer
3.3.1. Formation and Expansion of Bubbles
3.3.2. Formation of Single and Double Peaks
4. Conclusions
- There was a critical laser fluence for the continuous line transferred. Different transfer states were observed under different laser fluences: non-formed lines or formed but no continuous lines (below threshold), continuous formed lines (critical and above threshold), and explosive formed lines (much higher than the critical threshold).
- At the processing speeds of 5000 mm/s, 2500 mm/s and 1000 mm/s, the critical transfer thresholds were 1.32 J/cm2, 0.96 J/cm2, and 0.65 J/cm2, respectively. A larger transfer threshold was required at higher processing speeds. As the laser fluence increased, the line width increased significantly.
- For the continuous line transfer, cross-sectional morphologies of the formed line with single and double peaks were observed at the critical and above transfer threshold, respectively. The highest point of single peak appeared at top of the protrusion, accompanied by a gradual rise of the edges. While two symmetrical protrusions with steep edges were shown for the formed line with double peaks. The height difference between the middle and edge decreased with the increase of laser fluence.
- By comparing the silver paste remaining on the donor and transferred to the acceptor, it was found the silver paste transferred on the acceptor exhibited a retracting characteristic under the critical and above the transfer threshold. While a stretching characteristic was exhibited when the laser fluence was much higher than the transfer threshold. Under the action of the axial combined forces (G, τ, Fv, Fe, Fa, and Fn), the distance between the rupture position of the bridge and the bottom of the bubble determined the morphological characteristics of single or double peaks.
Author Contributions
Funding
Institutional Review Board Statement
Data Availability Statement
Conflicts of Interest
References
- Shan, Y.; Zhang, X.; Li, H.; Zhan, Z. Single-step printing of high-resolution, high-aspect ratio silver lines through laser-induced forward transfer. Opt. Laser Technol. 2021, 133, 106514. [Google Scholar] [CrossRef]
- Gupta, N.; Rao, K.D.M.; Gupta, R.; Krebs, F.C.; Kulkarni, G.U. Highly Conformal Ni Micromesh as a Current Collecting Front Electrode for Reduced Cost Si Solar Cell. ACS Appl. Mater. Interfaces 2017, 9, 8634–8640. [Google Scholar] [CrossRef] [PubMed]
- Adrian, A.; Rudolph, D.; Willenbacher, N.; Lossen, J. Finger Metallization Using Pattern Transfer Printing Technology for c-Si Solar Cell. IEEE J. Photovolt. 2020, 10, 1290–1298. [Google Scholar] [CrossRef]
- Sopeña, P.; Fernández-Pradas, J.M.; Serra, P. Laser-induced forward transfer of conductive screen-printing inks. Appl. Surf. Sci. 2020, 507, 145047. [Google Scholar] [CrossRef]
- Munoz-Martin, D.; Chen, Y.; Morales, M.; Molpeceres, C. Overlapping Limitations for ps-Pulsed LIFT Printing of High Viscosity Metallic Pastes. Metals 2020, 10, 168. [Google Scholar] [CrossRef] [Green Version]
- Delaporte, P.; Alloncle, A.P. [INVITED] Laser-induced forward transfer: A high resolution additive manufacturing technology. Opt. Laser Technol. 2016, 78, 33–41. [Google Scholar] [CrossRef]
- Arnold, C.B.; Serra, P.; Pique, A. Laser direct-write techniques for printing of complex materials. MRS Bull. 2007, 32, 23–31. [Google Scholar] [CrossRef] [Green Version]
- Serra, P.; Pique, A. Laser-Induced Forward Transfer: Fundamentals and Applications. Adv. Mater. Technol. 2019, 4, 1800099. [Google Scholar] [CrossRef] [Green Version]
- Biver, E.; Rapp, L.; Alloncle, A.-P.; Delaporte, P. Multi-jets formation using laser forward transfer. Appl. Surf. Sci. 2014, 302, 153–158. [Google Scholar] [CrossRef]
- Patrascioiu, A.; Florian, C.; Fernandez-Pradas, J.M.; Morenza, J.L.; Hennig, G.; Delaporte, P.; Serra, P. Interaction between jets during laser-induced forward transfer. Appl. Phys. Lett. 2014, 105, 014101. [Google Scholar] [CrossRef]
- Sanchez-Aniorte, M.I.; Mouhamadou, B.; Alloncle, A.P.; Sarnet, T.; Delaporte, P. Laser-induced forward transfer for improving fine-line metallization in photovoltaic applications. Appl. Phys. A-Mater. Sci. Process. 2016, 122, 595. [Google Scholar] [CrossRef]
- Shan, Y.; Zhang, X.; Chen, G.; Li, K. Laser induced forward transfer of high viscosity silver paste on double groove structure. Opt. Laser Technol. 2022, 148, 107795. [Google Scholar] [CrossRef]
- Zhou, Y.Y.; Tong, H.; Liu, Y.J.; Yuan, S.L.; Yuan, X.; Liu, C.; Zhang, Y.C.; Chen, G.R.; Yang, Y.X. Rheological effect on screen-printed morphology of thick film silver paste metallization. J. Mater. Sci.-Mater. Electron. 2017, 28, 5548–5553. [Google Scholar] [CrossRef]
- Green, M.A. Third generation photovoltaics: Ultra-high conversion efficiency at low cost. Prog. Photovolt. Res. Appl. 2001, 9, 123–135. [Google Scholar] [CrossRef]
- Kattamis, N.T.; Brown, M.S.; Arnold, C.B. Finite element analysis of blister formation in laser-induced forward transfer. J. Mater. Res. 2011, 26, 2438–2449. [Google Scholar] [CrossRef] [Green Version]
- Chen, Y.; Morales, M.; Munoz-Martin, D.; Molpeceres, C. Influence of the acceptor roughness on the aspect ratio of silver paste lines printed by laser-induced forward transfer. Results Phys. 2016, 6, 998–999. [Google Scholar] [CrossRef]
Properties | Value |
---|---|
Solid content | 90–92% |
Average fineness | 3–5 μm |
Viscosity | 160–350 Pa·s |
Donor | Acceptor | ||||
---|---|---|---|---|---|
No-Transferred | Protrusion Width (μm) | Protrusion Height (μm) | Line Width (Unsintered, μm) | Line Height (Unsintered, μm) | |
Laser Fluence (J/cm2) | |||||
Below critical threshold | 0.50 | 34.11 | 3.08 | / | / |
0.55 | 39.61 | 4.60 | / | / | |
0.60 | 41.62 | 5.75 | / | / | |
Transferred | Slit Width (μm) | Slit Height (μm) | Line Width (Unsintered, μm) | Line Height (Unsintered, μm) | |
Laser Fluence (J/cm2) | |||||
Critical transfer threshold | 0.65 | 36.55 | 15.77 | 27.74 | 27.35 |
Above critical threshold | 0.70 | 38.08 | 15.95 | 34.00 | 23.70/15.18 |
0.75 | 44.97 | 16.17 | 49.35 | 23.73/20.10 | |
Much higher than critical threshold | 0.90 | 74.34 | 16.16 | 77.67 | 24.03/14.20 |
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Zhang, Y.; Tian, C.; Yu, Y.; He, X.; Bian, Y.; Li, S.; Yu, G. Morphological Characteristics and Printing Mechanisms of Grid Lines by Laser-Induced Forward Transfer. Metals 2022, 12, 2090. https://doi.org/10.3390/met12122090
Zhang Y, Tian C, Yu Y, He X, Bian Y, Li S, Yu G. Morphological Characteristics and Printing Mechanisms of Grid Lines by Laser-Induced Forward Transfer. Metals. 2022; 12(12):2090. https://doi.org/10.3390/met12122090
Chicago/Turabian StyleZhang, Yanmei, Chongxin Tian, Yucui Yu, Xiuli He, Yanhua Bian, Shaoxia Li, and Gang Yu. 2022. "Morphological Characteristics and Printing Mechanisms of Grid Lines by Laser-Induced Forward Transfer" Metals 12, no. 12: 2090. https://doi.org/10.3390/met12122090