关键词: 纳米铜颗粒, 线路修复, 激光烧结

Abstract: copper nanoparticles areprepared by liquid-phase reduction method and mixed with ethylene glycol solvent to form a paste. UV laser is used to repair the missing part of the circuit on copper printed circuit boards.The effects of different laser power, speed and frequency on the morphology and properties of the repaired lines are investigated, and the optimal process parameters are obtained. No obvious rule is found in the resistance value and laser power of the repaired line.The best performance of the repaired line is obtained with a laser power of 0.4 W, a speed of 100 mm/s, and a frequency of 150 kHz, with a flat surface and no cracks. Its resistance is only 0.2 Ω (with a resistivity of 4×10^-6 Ω·m).After bending test, the copper wire at the bend is partially separated due to stress, and the resistance value of the line showes an increasing trend with the increase of bending times. The resistance value after 4 bends is 9 times higher than that before bending.

Key words: copper nanoparticles, wire repair, laser sintering