Laser processing technology provides a feasible method for directly manufacturing printed circuit boards (PCBs) using polytetrafluoroethylene (PTFE) material, however, the parameters during the laser fabrication process have a significant influence on the adhesion strength of electroless copper foil on PCBs. In this study, a 355 nm picosecond pulsed laser was used to fabricate electroless copper foil on the PTFE surface, and the aim of this work was to relate the adhesion strength and surface roughness Ra to the laser processing parameters (laser power, scanning speed, scanning line interval, and pulse frequency) and to find out the optimal manufacturing conditions. The Box-Behnken design (BBD) method in response surface methodology (RSM) was employed for experimental design. A regression model has been developed for analyzing the resulting data. Analysis of variance, perturbation plots, and 3D response surface plots were conducted to evaluate the effects of parameters on the Ra and adhesion strength. Numerical analysis indicated that the optimized laser power, scanning speed, scanning line interval, and pulse frequency on the adhesion strength were 5.4 W, 1439.3 mm/s, 17.2 μm, and 388.7 kHz, respectively. Additionally, the predicted results nearly agree with the actual values, indicating that the developed mathematical models can predict the adhesion strength adequately within the limits of laser processing parameters used.
Zhou et al. (2026) studied this question.