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PCB Copper Trace Finish

Posted: Sun Dec 23, 2018 3:28 am
by Nikosant03
Hi everyone,

I'm new pcb designer and I need your guidance.
I design a 4-layer board in Eagle and some of the traces will carry RF signals. I want the trace finish carrying the RF signals to be solder mask free and covered with gold finish as well as the pads that SMA connector is going to be soldered.

How can I declare this specification to the PCB manufacture?

Thanks in advance

Re: PCB Copper Trace Finish

Posted: Mon Dec 24, 2018 9:31 am
by n1ist
There are two parts to this.
- You specify the lack of a mask by creating a void in the solder mask layer on your board; from a previous post with this question:
I'm not sure if there is a direct way to do it with the trace properties but what you can do is draw an identical wire on top of the trace you want exposed but change its layer to "tstop" or "bstop" (top/bottom). The STOP layers are used to define areas where the solder mask does not exist. It's typically used in a polygon to unmask a large area but you can use it with individual wires as well.
- You specify the gold plating by using a PCB process that has ENIG (electoless nickel immersion gold) finish. This may be done with a selection while placing your order or as a special manufacturing note to the fab house.
/mike

Re: PCB Copper Trace Finish

Posted: Mon Dec 24, 2018 10:19 am
by Nikosant03
Thanks Mike!! That was really helpfull!!

Nick