CC BY
13
ALV22-- LM"1"14
LASER-MATTER INTERACTION
Direct laser writing of copper micropatterns from deep eutectic solvents:
chemical and physical aspects
Lev Logunov Ekaterina A. Avilova Evgeniia M. Khairullina 2, Andrey Yu. Shishov 2, Aleksandra
Levshakova 2, Dmitry A. Sinev Ilya I. Tumkin2
'School of Physics and Technology, ITMO University, 197101 St. Petersburg, Russia; 2Institute of Chemistry, Saint Petersburg University, SPbU, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia
e-mail: [email protected], +7 911 127 9134
In comparison with traditional methods such as photolithography and processes occurring at high vacuum, additive technologies are promising and rather cheap for fabrication of materials on different surfaces, including polymers. It is known that recently the demand for various optoelectronic devices such as liquid crystal displays (LCDs), touch screens, solar cells, organic light-emitting diodes (OLED) and electrochromic devices has been significantly increasing [1].
In this work, we present a new approach based on deep eutectic solvents (DES)-assisted synthesis of conductive copper structures using regular technique of laser-induced liquid deposition of metals (LCLD). The main benefits of such a modified LCLD are no need to use vacuum chamber or photomasks and simplicity of the step that includes DES preparation.
Along with this, the vector of modern industrial microelectronics technologies is shifting annually towards the development and application of more environmentally friendly approaches. Deep eutectic solvents have been gaining popularity for the last 10 years as "green" solvents. Thus, the use of such systems seems extremely relevant, taking into account the replacement of traditional approaches with more environmentally friendly ones. At the same time, working with DES is hampered by the high lability of these compounds. In turn, the covering process is also associated with adhesion to the substrate surface, which is affected by the chemical affinity of the components and the substrate material. For example, it was shown that the process of film covering on the substrate or membrane surfaces is usually stepwise and includes heating, covering of a film using spin coating and final annealing (depends on the composition of DES).
The current work is focused on modification of the LCLD method, in which deposition of metallic layers and structures from solutions containing cheap and simple components occurs upon cw or pulsed radiation. The advantages of this method are simplicity, low reagent consumption, the ability to control the shape and size of structures with an optical circuit and the low cost of reagents. The main limitation of this method was the speed of fabrication, which did not allow scaling this technology. However, recently, it was shown that it is possible to increase the deposition rate of copper by an order of magnitude by using deep eutectic solvents (DESs) as a medium for laser synthesis [2].
Figure 1. Copper patterns deposited from DES.
1.1. T., E. M. K., and A.S.L. acknowledge Russian Science Foundation (grant 20-79-10075). The authors would like to thank the SPbSU Nanotechnology Interdisciplinary Centre, Centre for Physical Methods of Surface Investigation, Centre for Innovative Technologies of Composite Nanomaterials, Centre for Optical and Laser Materials Research and Centre for X-ray Diffraction Studies.
references:
[1] Bhuiyan, M. E. H.; Behroozfar, A.; Daryadel, S.; Moreno, S.; Morsali, S.; Minary-Jolandan, M. A Hybrid Process for Printing Pure and High Conductivity Nanocrystalline Copper and Nickel on Flexible Polymeric Substrates. Sci. Rep. 2019, 9 (1), 1-10. https://doi.org/10.1038/s41598-019-55640-7.
[2] Shishov, A.; Gordeychuk, D.; Logunov, L.; Tumkin, I. High rate laser deposition of conductive copper microstructures from deep eutectic solvents. Chem. Commun., 55, 9626-9628, (2019).
