-
- News
- Books
Featured Books
- pcb007 Magazine
Latest Issues
Current IssueVoices of the Industry
We take the pulse of the PCB industry by sharing insights from leading fabricators and suppliers in this month's issue. We've gathered their thoughts on the new U.S. administration, spending, the war in Ukraine, and their most pressing needs. It’s an eye-opening and enlightening look behind the curtain.
The Essential Guide to Surface Finishes
We go back to basics this month with a recount of a little history, and look forward to addressing the many challenges that high density, high frequency, adhesion, SI, and corrosion concerns for harsh environments bring to the fore. We compare and contrast surface finishes by type and application, take a hard look at the many iterations of gold plating, and address palladium as a surface finish.
It's Show Time!
In this month’s issue of PCB007 Magazine we reimagine the possibilities featuring stories all about IPC APEX EXPO 2025—covering what to look forward to, and what you don’t want to miss.
- Articles
- Columns
Search Console
- Links
- Media kit
||| MENU - pcb007 Magazine
Estimated reading time: 4 minutes

Plated Through-holes in Flexible Circuits
Figure 4: Carbon deposited on dielectric.The Shadow process ultimately leaves conductive carbon only where it is needed. The carbon-coated through-hole can now be electroplated as shown below:
Figure 5: Electroplated copper over carbon.
It is important to note that both the Shadow and electroless processes are only used to create the conductive bridge. Neither coating is robust enough to withstand environmental stress or conductive enough to carry significant current.
The Shadow Process vs. Electroless Copper
Some flexible circuit manufacturers are primarily using electroless copper and some are using conductive carbon. Each process has its benefits and drawbacks.
Page 3 of 4
More Columns from All About Flex
All About Flex: Terms and ConditionsAll About Flex: ISO 9001 Basics
All About Flex: FAQs on UL Listings for Flexible Circuits
All About Flex: Avoiding Trace Fracturing in a Flexible Circuit
Polyimide vs. Silicone for Flexible Heaters
All About Flex: Copper Thickness Requirements for Flex Circuits
All About Flex: Copper Grain Direction
All About Flex: Options for Purchasing Flexible Heaters