Spacing between copper layers in Multilayer PCB

Hi there,

I’m relatively new to KiCAD and want to design a RF-board with CPW structures. Therefore, I need to control the distance of two copper layers in a multilayer setup.
As you can see in the Appendix, I just created 4 layers of copper and a buried via from the top to the first inner layer for visibility. For my board I now need to control the spacing between those two layers while the spacing of the other layers is not important.

Is there a way to tell KiCAD how far those layers should be apart?

Thank you!


No, KiCad lacks a board stackup.
The overall thickness can be set, that’s all.

Why is it critical to get KiCad to describe each layer accurately? The actual layer thickness matters for impedance calculations only and to be communicated with the PCB fab

Hi david, thanks for the quick reply.

Okay, good to know.

In the end I want to import the GerberFiles in CST Microwave Studio to do some simulations upon fabrication, this is why I thought it might be crucial to already have it in KiCAD.

Version 5.99, the unstable development version, has a stackup editor. You could try it and see what it can do. Copy your project and open the copy with a nightly build. You should of course edit the original layout only with 5.1 because after making changes in 5.99 it will be incompatible.

1 Like

How does CST Microwave Studio determine the stackup from gerber files?

Maybe the ODB++ format contains the stackup info.

@Weazler. For getting the geometry for FEM simulations FreeCad macro fcad_pcb is by my knowledge the best option. But currently it does not support the stackup info present in 5.99

Yes, if using ODB++ it has the stackup. But regular Gerbers do not.

KiCad outputs at least some of the stackup information to “gerber job” file if that file is selected as an option when generating gerbers.

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.