PCB Copper Foil (RA, ED)

PCB copper foil

PCB Copper Foil | PCB Manufacturer in India

  • Copper foil comes in two forms

                 − Electrodeposited (ED)

                 − Rolled and Annealed (RA)

    RA Copper PCB
    • RA copper is used primarily for Flex and Microwave applications, while ED copper foil is the most commonly used in the industry for all other printed circuit applications

    Rolled Annealed (RA) Copper Foil Process 

    • In several passes, the rolling mill reduces the copper thickness until it produces copper foil suitable printed circuits. It is then annealed and treated for adhesion.

    Rolled Annealed Copper Foil- Rolled Annealed copper foil is mainly used in flex applications for its ductility and in microwave applications smooth surface finish.

    • RA foil’s crystalline grain structure is oriented parallel to the foil plane
    • The rolling process creates a very smooth surface reducing skin resistance and becomes very beneficial at frequencies above about 15 GHz
    • Rolled copper foil is considerably more expensive than ED foil
    • RA foil has lower peel strength and lower resolution etching than ED foil
    • New ED copper foils with very fine non-columnar grain structures are starting to replace RA foil in some applications

    Electro Deposited Copper Foil Process

    ED Copper Foil Process
    • As the drum rotates slowly clockwise, copper is plated onto the drum.  After 180 degrees rotation, the copper is at its final thickness and it is removed from the drum in a continuous web.

    Electro Deposited Copper Foil Structure

    Electrodeposited copper foil has two surfaces.  The drum side is basically an image of the drum surface and is quite smooth, while the matte side exhibits dendritic features.

    • Copper foil requires a surface treatment prior to bonding prepreg resins
    • Surface treatment can be applied to either side or both
    • Some resins can require different treatments


    Cerra Systems is one of the leading PCB manufacturing solutions providers with PCB manufacturing plants located in North America, Asia with certifications for MIL, AS, TS, ISO, & NADCAP. Our products are Rigid, Flex, Rigid-flex, HDI, RF, and hybrid PCBs addressing up to 64 layers and 2 mil technology. Cerra Systems  Major  PCB Market is Aerospace, defense, Medical, computing, cellular & Industrial. PCB Manufacturer Company in India

    For more information, visit- http://cerrasystems.com/

    Manufacturing Partners Profile includes: 
    Argus Sytems (AESPL) –  PCBACable AssemblyBox Build
    Emsxchange – PCBA, Cable Assembly, Box Build.