immersion gold is ion exchange process (correct me if I am wrong).   
only very thin layer can be formed on the surface.  the roughness  
must be underlying layer or substrate plating issue... IMHO.  Not  
sure what actually the supplier of his was saying (it might be lost  
in communication).
The electroless Nickel, unless it is porous (with bubbles or P or  
additive clusters), it usually not rough either...Let me know if you  
guys observe something else in the past...
jk
On Jun 28, 2018, at 3:39 AM, FTL Quality wrote:

> Do you have some pictures to illustrate the issue?
>
> Thanks
>
> -----Original Message----- From: Wayne Showers
> Sent: Wednesday, June 27, 2018 7:57 PM
> To: [log in to unmask]
> Subject: [TN] Rough Gold causing plating shorts
>
> I need a favor in regard to rough gold (ENIG) causing plating  
> shorts.  I need a brief synopsis of which process or processes  
> typically go out of balance to cause this issue.
> Basis: My supplier is indicating electrical shorts attributable to  
> rough gold being the reason for their low lot yields on a rigid  
> flex. Unfortunately, I know enough to be dangerous but not  
> necessarily effective in this realm.