Victor,

If you need to use alkaline etchant for making inner layers, tin plating is
useful.   Modern photoresists  are sensitive to alkaline solutions.  If you
have buried vias in the cores that require copper pattern electroplated via
holes, then alkaline etching and hence tin plating is useful.

You can use photoresist only for cupric chloride etching of double sided
copper cores without holes, or if you panel plate the two entire copper
surfaces including any buried via holes, then you can "tent and etch" the
pattern you want, and etch with cupric or other acid etchants.

Hope this helps.

Denny Fritz

On Tue, Jan 28, 2020 at 1:09 PM <[log in to unmask]> wrote:

> Fellow TechNetters:
>
>    Can tin plating of some sort be used on copper core for a DES
> processing?
> All I can remember was photo resist in the OLD days........
>
> Victor,
>


-- 
Denny Fritz
Consultant
812 584 2687