Verification of a characterization method of the laser-induced selective activation based on industrial lasers

In this article, laser-induced selective activation (LISA) for subsequent autocatalytic copper plating is performed by several types of industrial scale lasers, including a Nd:YAG laser, a UV laser, a fiber laser, a green laser, and a short pulsed laser. Based on analysis of all the laser-machined surfaces, normalized bearing area curves and parameters are used to characterize the surface quantitatively.

The range of normalized bearing area curve parameters for plate-able surface is suggested. PBT/PET with 40 % glass fiber was used as the substrate material. For all of the studied lasers, the parameters were varied in a relatively large range, and matrixes of the laser-machined surface were obtained.

The topography of those laser-machined surfaces was examined by scanning electronic microscope (SEM). For each sample examined by SEM, there was an identical workpiece plated by for 90 min. The obtained copper thickness was measured. It is confirmed that copper only deposits on the surface that has a porous structure.

The bonding strength between the copper layer and the substrate was also measured.