Preparation Technology of Stretchable Electrode Based on Laser Cutting

Abstract

Wearable electronics have showed their profound impact in military, sports, medical and other fields, but their large-scale applications are still limited due to high manufacturing costs. As an advanced micro-fabrication process, laser processing technology has the advantages of high speed, high flexibility, strong controllability, environmental protection and non-contact in preparing micro-nano structures of wearable electronics. In this paper, a 355 nm ultraviolet laser was used to pattern the copper foil pasted on the flexible substrate, and the interconnection electrodes and wires were constructed. A processing method of multi-parallel line laser cutting and high-speed laser scanning is proposed to separate and assist in peeling off excess copper foil. The process parameters are optimized. A stretchable 3 × 3 light-emitting diode (LED) array was prepared and its performance was tested. The results showed that the LED array can work normally under the conditions of folding, bending and stretching, and the stretch rate can reach more than 50%. A stretchable temperature measurement circuit that can be attached to a curved surface was further fabricated, which proves the feasibility of this process in the fabrication of small-scale flexible wearable electronic devices. Requiring no wet etching or masking process, the proposed process is an efficient, simple and low-cost method for the fabrication of stretchable circuits.

Flexible pressure sensor constructed by polyurethane composite conductive sponge

“…With the rapid rise and development of wearable electronic devices, the demand for high-performance flexible sensors is increasing. Flexible strain sensors have attracted extensive research attention in recent years, and have shown broad application prospects in the fields of motion monitoring, medical equipment, consumer electronics, electronic skin and soft robots [1][2][3][4][5][6]. For example, in prosthetics and robotics applications, strain sensors can monitor the bending of joints, fingers, etc., in order to achieve health status assessment [7,8].…”