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10LS"°"5 M' ALT'22
LASER SYSTEMS AND MATERIALS
Spin-coating of deep eutectic solvent for film formation for fabrication of copper patterns using picosecond laser irradiation
L. Logunov1, D. Shestakov2
- School of Physics and Engineering, ITMO University, Lomonosova, 9, Saint-Petersburg, 191002, Russia Department of Physical Electronics and Technology, Saint PetersburgElectrotechnical University "LETI", 197376
Saint Petersburg, Russia Main author email address: [email protected]
Local metallization of dielectrics is an important practical task; inkjet and laser sintering have been developed in industry today. However, each of them has its drawbacks, for Inkjet - the cost of ink, the limitation on the thickness and width of the print area; for laser sintering - the cost of nanoparticles for sintering, damage of the substrate, restrictions on the materials used, and a complex procedure for removing unreacted material [1].
We investigate laser induced chemical deposition method, it is a promising way to template-free metallization methods. The method makes it possible to create metal structures locally on the surface in the zone of laser radiation focus. The advantages of the method include simplicity, low consumption of reagents, the ability to control the shape and size of structures by an optical scheme, low cost of reagents, and environmental friendliness. In addition, the method makes it possible to obtain various metals and their compounds by simply selecting the solution components [2]. Previously, it was possible to obtain conductive metal structures at a scanning rate of 50 um/s using deep eutectic solutions and CW laser radiation [3].
In this work, it was possible to increase the rate of obtaining current-conducting structures on the glass surface by more than an order of magnitude. The maximum scanning speed was 10 mm/s with a resistivity 0.13 Q mm2/m. We have developed a new method for obtaining thin films of DEC, which made it possible to achieve such results. The process of applying DES films includes several stages and is shown in Figure 1. The first step is to prepare the substrates by the standard cleaning method, then the DES sample is diluted with H2O in a ratio of 3:1 by weight, after solution is spin-coated on the glass surface, samples are dried for 15 minutes on a hot plate at 90C. Then we used galvo scanner with picosecond laser (7pc,1064 nm, 80 mHz) for pattern creation, the unreacted solution is washed off with hot water.
Fig 1. a- initial DES, b - DES with adds of water, b-wet film of DES solution applied by spin-coating, d-dried film of DES solution, e-laser patterning, f-washed sample.
[1] Naghdi, S.; Rhee, K. Y.; Hui, D.; Park, S. J. A Review of Conductive Metal Nanomaterials as Conductive, Transparent, and Flexible Coatings, Thin Films, and Conductive Fillers: Different Deposition Methods and Applications. Coatings, 8 (278), 1-27 (2018).
[2] Logunov, L. S.; Panov, M. S.; Myund, L. A.; Tumkin, I. I.; Khairullina, E. M.; Ryazantsev, M. N.; Balova, I. A.; Kochemirovsky, V. A. Influence of the Ligand Nature on the in Situ Laser-Induced Synthesis of the Electrocatalytically Active Copper Microstructures. Arab. J. Chem. 11 (5), 624-634 (2018).
[3] Shishov, A.; Gordeychuk, D.; Logunov, L.; Tumkin, I. High Rate Laser Deposition of Conductive Copper Microstructures from Deep Eutectic Solvents. Chem. Commun. 55 (2019).
