Additives are a cost-effective method to improve the performance of the very low profile (HVLP) copper foil coarsened layer. In this paper, the effects of 3,3’-Dithiobis-1-propanesulfonic acid disodium salt (SPS), gelatin, and sodium thiazoline dithiopropane sulfonate (SH110) concentration on the morphology, roughness, and peel strength of HVLP copper foil was reported. The results show that SH110 contributes significantly to the reduction of copper foil roughness, improvement of peel strength, and refinement of coarsened layer grains. In addition, the linear scanning voltammetry and AC impedance spectroscopy of the solution were carried out to understand the action mechanism of additives on the copper foil surface. The results demonstrate that SPS promotes the copper deposition process due to the presence of sulfonic acid groups(–SO 3 ). The amino group(–NH 2 ) of gelatin inhibits copper deposition. SH110 has both promoter (Sodium 3-Mercapto-1-Propane Sulfonate, MPS) and inhibitor (Tetrahydrothiazolidinone, H1) fragments, which achieve synergistic or competitive effects consistent with the composite additive. Graphical abstract
The electrochemical behavior of additives determinates the filling process of through ceramic holes (TCHs), which is severely affected by Cu(II) concentration in the virgin make-up solution (VMS). High concentrations of Cu(II) are rarely reported in through-holes (THs) filling owing to its insufficient throwing power. High concentration CuSO 4 (0.7 M) and low concentration H 2 SO 4 (0.61 M) were confirmed as VMS, and thiazolinyl polydipropyl sulfonate (SH110), polyethylene glycol (PEG), and nitrotetrazolium blue chloride (NBT) were chosen as the accelerator, suppressor, and leveler, respectively. The electroplating performances were investigated under different plating solutions. The electrochemical behavior of additives and their combinations were evaluated by galvanostatic and cyclic voltammetric measurements. The filling performance of PEG-SH110-NBT in high Cu(II) solution is affected by convection. Plating efficiency is effectively improved by SH110 in the designed high Cu(II) plating solution. PEG and NBT have a synergistic effect on inhibition, while NBT shows a leveling effect only in the presence of SH110. The plating solution with a low air agitation flow rate effectively promotes the high-quality filling of TCHs with a high aspect ratio (AR) of 5, 4.75, and 3.8. The filled TCHs display mirror-bright surface and grain refinement without the void defects.
危险品化学品经营许可证（带存储）