We are into designing an RF circuit.I want to know if green masking on the both sides of board will do any good.What will be its effect?
And what about impedance matching?Do we need to take some special care to achieve it?
Thanks in advance.
Short answer: No.
Long answer: I'm doing RF design, and soldermask doesn't seem to affect performance, but it will depend on what you're designing. If it's a 'tuning circuit' or antenna, or something specific, soldermask may affect the performance. As for impedance, it won't make a difference.
In reply to Cadpro2K:
Cadpro2KAs for impedance, it won't make a difference.
As for impedance, it won't make a difference.
Absolutely affects impedance given two identical copper traces, one with mask, one without.
Also affects propagation velocity but that may not be of concern.
In general, I recommend mask over copper for protection. Adjust the width accordingly to meet impedance requirements and you'll be OK.