Smallest font - covered vias

[Jester]

I'm doing a very dense RF layout with a lot of ground stitching vias. My normal practice is to use true type font Arial 45 mils. If I specify DLP process instead of silkscreen method this seems to make for legible designators as long as I don't place the designators on top of vias.

Can I place the designators on top of vias and expect good legibility if I specify covered vias?

 

[Mattylad]

No.

The resist still goes down the via.

 

[ArticCynda]

I've done as low as 40 mil size and 8 mil trace widths for component overlays, also over vias. For stitching vias it doesn't really matter, but don't do it for signal vias: it adds unpredictable capacitance and eliminates the advantage of using the via as a test point in the production process.