Characteristics of laser solder mask on nickel-plated copper-clad substrate

In order to avoid bridging, deflection and other defects in welding process of close-range components on nickel-plated copper-clad substrates, and to improve welding reliability, the method of laser beam etching on the nickel layer was used to develop the solder mask process. The laser parameters were selected and optimized through orthogonal experiments. The results showed that when the laser pulse current was 14 A, the modulation frequency was 5. 0 kHz, and the laser step was 0. 4, a good solder mask effect could be obtained. The solder mask pattern was further designed and optimized, and finally determined that the width of the solder mask area was less than 100 μm, which greatly improved the component placement and soldering density.