Fast Fabrication of Conductive Copper Structure on Glass Material Using Laser-Induced Chemical Liquid Phase Deposition

Abstract

Glass is a very stable material at room temperature and has good resistance to gas, bacteria, and organisms. Due to the development of the electronic industry, the industrial demand for creating a conductive pattern on glass is increasing rapidly. To create conductive circuit patterns on the glass surface, non-contact methods based on high energy sources or chemical methods are generally used. However, these methods have disadvantages such as low conductivity, high cost, and size limitations. Processes such as LCLD (laser-induced chemical liquid phase deposition) have been widely studied to solve this problem. However, it has a fatal disadvantage of being slow. Therefore, in this study, various process changes were attempted to improve productivity and conductivity. In particular, sufficient thermal energy was supplied with high laser power for a stable chemical reduction, and the scanning path was changed in various shapes to minimize the ablation that occurs at this time. Through this, it was possible to disperse the overlapped laser energy of high power to widen the activation area of the reduction reaction. With this proposed LCLD process, it is possible to achieve good productivity and fabricate conductive circuit patterns faster than in previous studies.

One-Stage Femtosecond Laser-Assisted Deposition of Gold Micropatterns on Dielectric Substrate

“…The obtained value is rather high in comparison, with the resistivity of bulk gold (0.0023 mΩ·cm) due to the presence of pores formed during the gold nanoparticles aggregation. However, it is comparable with the results demonstrated for laser-deposited copper electrodes [ 5 , 6 ]. This indicates satisfactory quality and potential in electrical applications of laser-fabricated gold traces.…”

“…The second and subsequent passes enable intensive gold deposition so that gold is formed not only in the groove but also outside it on the glass surface. It should be noted that opposite to copper deposition, where a reducing agent in the solution and alkaline condition is required to launch a laser-induced chemical reaction of copper reduction [ 5 ], exposure to femtosecond pulses opens a way to the direct laser-induced reduction of metal due to the availability of free electrons produced via multiphoton ionization. Optical images of the laser-written tracks show that even a single laser beam pass is sufficient for gold reduction and deposition.…”

“…A FemtoLab laser micromachining setup based on Pharos SP femtosecond Yb:KGW laser (Light Conversion Ltd., Vilnius, Lithuania) emitting 1030 nm pulses with 180 fs duration was used for direct laser writing. The pulse energy was tuned in the range of 100 to 800 nJ, and the repetition rate was set to 500 kHz to provide heat accumulation and the thermal mode of laser processing which is favorable for metal reduction and deposition [ 5 ]. The scheme of laser-assisted gold micropatterning is shown in Figure 1 .…”

“…Over the past decade, approaches to the laser-assisted metallization of dielectrics based on laser-induced chemical liquid phase deposition have been well developed [ 4 ]. Most studies were performed using continuous-wave [ 5 ] or nanosecond [ 6 , 7 ] laser sources for copper deposition while metal salt solution served as a light absorber. However, femtosecond laser irradiation provides the possibility of using any solutions, regardless of their absorption, better precision in the formation of complex metal structures, and control of their morphology while maintaining high process efficiency [ 8 , 9 ].…”

Conductive polyacrylate coatings filled with bimetal Cu–Ni, Zn–Cu, or Zn–Ni powders and graphene nanoplatelets

“…It should be noted that the choice of silicate glass as a substrate for conductive coatings is not accidental. Conductive coatings on transparent glass are widely used in various fields including automobiles, shipbuilding, and aviation, as well as optical devices, displays, and biochips such as transparent antenna, defrosting of large glass, touch screens of smartphones, and so on 46 …”