Ultraviolet Laser-Induced Selective Metallization on White Polymers Using Oxygen Vacancy Laser Sensitizer for IoT Sensors

As the world enters the Internet of Things (IoT) era, sensors, the key technology for IoT, are developing rapidly. Laser-induced selective metallization (LISM) has recently garnered significant interest as an additive manufacturing (AM) technique for the fabrication of sensor circuits. Herein, a strategy for preparing circuits on light-colored LISM substrates using ultraviolet (UV) laser-induced selective metallization based on an oxygen vacancy (OV) laser sensitizer was proposed, and an IoT photosensitive sensor was prepared through this strategy. The acrylonitrile-butadiene-styrene copolymer (ABS) resin combined with laser sensitizer zinc oxide (ZnO) was designed as LISM materials. ZnO can successfully perform UV LISM as a laser sensitizer but not near-infrared (NIR) LISM, and the mechanism was figured out. UV laser's photochemical and thermal effects led to the OV generated in the ZnO lattice. In addition, the UV laser's thermal effect caused ablation of the ABS/ZnO surface to produce rough structures. After the activation of the UV laser, the ABS/ZnO surface was subjected to the exposure of ZnO-containing OV, serving as active centers to trigger electroless copper plating (ECP). However, because of the limited photochemical response of the NIR laser, the activation of ZnO by the NIR laser resulted in little OV within the ZnO lattice and thereby cannot induce ECP. The presence of ZnO-containing OV made the copper layer prepared by UV LISM exhibit the ability of unlimited depletion and replating. In addition, the narrowest copper width prepared on ABS/ZnO by UV LISM was 31.82 mu m. Moreover, ABS/ZnO LISM materials with various colors could be prepared by adding trace dyes, which can be used in different application scenarios.

Automated summary

This paper proposes a strategy for preparing IoT photosensitive sensors on light-colored substrates using UV laser-induced selective metallization, and the mechanism of laser sensitizer is explored. Additionally, it is found that various colors of materials can be prepared by adding trace dyes for different application scenarios.