LASER ABLATION
Lasers of basically every kind can skiving polyimide product. CARBON DIOXIDE, YAG and also excimer lasers have all been made use of to accessibility metal functions with the cover film or coverlayer by ablation. Excimer lasers are slower compared to the others, much less effective and need even more maintenance, however they could generate sharp, distinct attributes. Lasers have also been utilized efficiently to precut coverlayer products for lamination.
Each of the laser technologies has advantages as well as disadvantages. Lasers are effective and quick, however they could also quickly ruin the flex PCB otherwise set up properly. Lasers likewise frequently leave a carbon char beside the cut product.
Still, newer lasers are greatly boosted over earlier versions and have actually shown to be cost-effective options.
No matter which kind is chosen, lasers transcend to mechanical skiving. They are presently as economical as mechanical drilling techniques. Lasers are highly valued for micro-via production, a modern technology which is comparable to giving backside access. Laser boring rates are impressive. Within a small area, drill prices of 10,000 openings per minute are frequently reported and by means of drill rates of as much as 15,000 vias each min are now possible for copper-clad flex PCB manufacturing and constructions. The productivity degree of lasers is vital to keeping made price down.
PLASMA ETCHING OF HOLES
Plasma etching of flex PCB material to attain back exposing is unusual due in part to the slowness of plasma etching compared to the other methods. While plasma is not well-suited to one-at-a-time and specific hole development, plasma can be economical for bulk or mass-quantity hole formation. The prep work of a panel for back baring by plasma etching includes using a metal mask that protects all surfaces, other than the areas of passion, from assault by the plasma.
One method used to complete this is layer the surface area of the cover film with a thin steel layer and after that etch openings over the preferred interconnect factor. An additional method is to preetch a metal mask and pin it to the flex PCB panel or part before processing. This technique, nonetheless, will not supply fairly as excellent an edge definition. A special benefit of plasma processing is that abnormally formed functions (e.g., square openings) can be created since the lithographic pattern specifies the function form.