Properties Of Copper Deposits Research Articles

Copper electrodeposition under a weak magnetic field: effect on the texturing and properties of the deposits

The effect of a weak magnetic field (induction of 0.5 to 0.7 mT) on the electrodeposition process and the formation of crystallographic texture, morphology and properties of copper deposits has been considered. Electrodeposition studies were performed using cyclic voltammetry, chronoamperometry, and chronopotentiometry. X-ray texture analysis and scanning electron microscopy observations were used to study the texture and the morphology of the copper deposits. Some of their properties were obtained by measuring their microhardness and reflectivity. The effects of decreasing the rate of copper electrodeposition, enhancing texture formation and refinement of grain aggregates of the surface of copper films under the influence of a weak magnetic field have been evidenced. The interrelation of the texture and morphology of the copper electrodeposit surface with their microhardness and reflectivity have been revealed. The conditions for obtaining copper deposits with enhanced microhardness and reflectivity have been determined. It is shown that the electrochemical deposition with a weak magnetic field is a promising direction for obtaining materials with desired properties, without using strong magnetic fields and adding surfactants to the electrolyte.

Peculiarities of Electroless Copper Deposition Using Environmentally-Friendly Natural Polyhydroxylic Compounds As Cu(II) Ligands

Cu(II) ligands are important components of common formaldehyde-containing alkaline electroless copper plating baths:Cu(II)-Ligand + 2CH2O(hydrated) + 4OH- → Cu + 2HCOO- + H2 + 2H2O + Ligand (1)From one hand, the ligands used should form Cu(II) complexes stable enough to prevent Cu(OH)2 formation, since the solubility product of Cu(OH)2 is of the order 10-18 and the concentration of “free” (uncomplexed) Cu(II) ions in the pH range 11–14 cannot exceed 10-12–10-18 M, respectively. On the other hand, it is worth to note that kinetics of copper deposition as well as the properties of copper deposits (compactness, exterior, morphology and crystal structure) in high extent depend on the nature of ligands used for Cu(II) binding into complexes in electroless copper plating solutions.The aim of the study presented herein was comparison of the parameters of process of electroless copper plating – mainly plating rate and nanoscale surface roughness of the copper deposits obtained, – using different polyhydroxylic ligands under the similar conditions.The ligands considered were glycerol, xylitol, D-mannitol, D-sorbitol and saccharose. Acknowledgement The work was carried out within the Project VP1-3.1 ŠMM-08-K-01-009 that is partly supported by the National Programme “An Improvement of the Skills of Researchers” launched by the Lithuanian Ministry of Education and Science.

Testing of Bright Copper Plating by Rotating-Cone Electrode in PCB Production

SummaryIn this study, bright copper deposit properties were investigated by means of a new rotating-cone electrode (RCE). This type of electrode was used because of reproducible and controlled mass-transfer performance at fixed rotation speeds. The influence of additives, temperature variations and current density on the properties of copper deposits from copper sulphate electrolyte was tested. The quality of bright copper deposit used as a conducting layer in printed circuit board production has influence on the reliability of electronic assembly.