Copper Plating
High tensile strength and elongation properties allows:
·
Increased expansion
· Contraction of plating in hole wall
Reduced copper plating thickness variation allows:
· Thickness readings from samplings to be trusted for entire production lots
· Reductions for target set thickness to insure minimum plating requirements
Chemistry component control is critical to plating performance. It requires the following:
· Proper test equipment;
· Frequent testing;
· Monitoring inorganic contaminants.
Variation Control
Copper plating systems can be optimized to achieve either:
·
Higher throughput
·
Higher quality
The key is to balance the two to achieve high reliability at a competitive cost.
Bare Board Cleanliness
·
Ionic contamination can lead to dendrite growth
·
Dendrites cause massive shorting across PCB surface after time in field
·
Ionic contamination is covered under IPC-5704
· Conformal coating is the most seamless method
· Use Saponifiers after soldermask application to disperse flux residue