antenna-theory.com

[Fadoua]

Hello everyone !

I need to choose a finish for my printed dipole. I found different types of plating on the internet : Ni/Au, HASL, silver, solder, OSP, Tin and I still have no idea for the moment what to choose for my pcb. I've read that Ni/Au is not a good choice for high frequencies (my target frequency is 6 GHz) due to skin effect with Nickel and that instead silver immersion is a good candidate for protecting my copper on RF frequencies . So I was wondering what do we usually use for finish plating antennas in the market? and if you have any ideas about solder, Tin and OSP plating on RF frequencies?


Thank you all for your kind help.

[admin]

You want the highest conductivity possible. Copper is more than fine and needs no new plating. If you're using a circuit board, probably half of your antenna is the ground plane, so if you're coating the antenna trace you are probably missing half the antenna anyway.

[Fadoua]

I need the finish to protect my copper from oxidation so as my circuit lasts for > 6 months.


I found an interesting article : http://www.microwavejournal.com/blogs/1-rog-blog/post/25177-finish-makes-a-difference-in-broadband-pcb-loss

[coundpake]

Usually when PCB antennas are used they're (and the rest of the board) coated in solder mask which prevents them from corroding - so they aren't usually plated. The parts that need to be exposed - like solder pads - are usually plated to prevent corrosion with tin, silver, gold, nickel or a mixture.

When high (MW and beyond) frequency parts need to be plated its definitely best to go with higher conductivity.