Often at the end of a PCB design there is unused space on the signal layers. It is important to fill this space because of:

  • The electroplating process (valid only for TOP and BOTTOM)
  • The even distribution of copper on internal layers ensures the boards are flat at the end

There are two ways people in the industry solve this:

  • Ground pours
  • Thieving dots

The way I see it is that in 95% of the cases it is better to use thieving, just because it is easier and the chance to create an issue is lower as compared to ground pours. I do understand that ground pour can be a sensible solution as well provided that you make sure that it is really well stitched and that it does not interfere with the impedances of your high speed signals. However, I don't understand what benefits it provides that would make it worth for me to put in the additional effort. Still a lot of people do it, so I was wondering if someone has a nice overview of all the pros and cons of both approaches.

  • 1
    \$\begingroup\$ There's a third way: hatch fills. Like ground pours but with less copper and the copper ridges add some mechanical stability \$\endgroup\$ May 26, 2022 at 12:56
  • \$\begingroup\$ Isn't that a thing of the past already or are they still people using it? \$\endgroup\$ May 27, 2022 at 7:34
  • \$\begingroup\$ I haven't seen dots or hatches in the last 20 years. Probably on some (cheaper) process they are still effective. Copper balance however can be an issue for board bending \$\endgroup\$ May 27, 2022 at 14:16

2 Answers 2


Rick Hartley gave a talk on advanced pcb design techniques that is available on YouTube. He is strongly against dots because dots float. floating things are uncontrollable EMI risks.

Now instead of mindlessly pouring ground one can also use this space to thicken the power distribution network.

But from my limited experience, the problem with thieving is not as severe and one can get away without fills most of the time.

  • \$\begingroup\$ May you put a link to the talk? Seems interesting. \$\endgroup\$ May 30, 2022 at 8:26
  • \$\begingroup\$ @IvanVlaykov I added the link. There is a section called "thief copper" in it. \$\endgroup\$
    – tobalt
    May 30, 2022 at 17:34

I think I found my answer. For anyone who might be interested I am posting it here.

I found a good discussion on this topic. In Eric Bogatin's book Bogatin's Practical Guide to Prototype Breadboard and PCB Design, in chapter 22, myth #2 it says that there is no compelling reason to use ground pours in signal layers, and that they can only cause problems if they are left poorly connected. I recommend everyone to take a look at this book.

  • \$\begingroup\$ "left poorly connected" is the definition of the dots. So are you actually reading a pro-dot recommendation into Bogatins statements? \$\endgroup\$
    – tobalt
    May 29, 2022 at 18:44
  • \$\begingroup\$ The dots are not connected at all (which in this case is better than loosely connected and they are quite small, which means that creating antennas from them is not a cause for concern for most PCB designs. So yes, I read a pro-dot recommendation. \$\endgroup\$ May 30, 2022 at 8:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.