Fabrication of Copper Patterns on a Curved Surface by Direct Laser Metallization from Deep Eutectic Solvents

Abstract

In recent years, the fabrication of conductive patterns on curved surfaces with a high-resolution and low-cost manner has attracted higher attention both from the scientific community and industry. Numerous studies were on the development of maskless metallization methods for various non-conductive materials, but few of them have shown results on curved surfaces. Here, we present for the first time the possibility of maskless metallization of a curved surface using direct laser metallization (DLM) from deep eutectic solvents (DES). The degree of shading, scanning speed, and number of scans were optimized for glass substrates with varying degrees of curvature. The obtained copper pattern have controlled roughness, excellent stability, and adhesion. A new milestone was achieved for deposition rate for this method (−18.8 mm s⁻¹). The resistivity of the copper layer measured using a four-point probe method is about 0.7 mΩ cm. As a proof of concept, we fabricated radio-frequency identification (RFID)FID tags on the curved silicate glass surface and measured their characteristics.