Aluminum foil tape?  EMI shielding tape?  do you have Z-axis contact  
risk if Al metal surface in contact with conductor?  good luck.
jk
On Aug 2, 2018, at 1:34 PM, Graham Collins wrote:

> Hello TechNet!
>
> I've got a customer who is looking to protect an IC from exposure  
> to UV.  It is a tiny 24 ball BGA (2.3 mm square).  They are  
> suggesting a dam and glob-top solution, but I'm concerned that  
> there isn't enough room around it (very, very small board).  I've  
> suggested a dab of black conformal coating material on a brush.   
> Any other great solutions?
>
> -- 
> Graham Collins
> Senior Process Engineer
> Sunsel Systems
> (902) 444-7867