Single-Side Roughened RA Copper Foil

Base Material: Electrolytic copper cathode with a purity of ≥99.99%.

Microstructure: Recrystallized equiaxed grain structure formed through multi-pass cold rolling and continuous annealing under a hydrogen atmosphere.

Treated Surface: The matte side receives a nodular micro-roughening treatment followed by an anti-oxidation passivation barrier.

Smooth Surface: The reverse side remains untreated and controlled to provide a low-roughness surface for high-frequency signal transmission.

Single-Side Interfacial Adhesion

The treated side has a controlled roughness profile that increases mechanical interlocking with polyimide (PI) or liquid crystal polymer (LCP) films. The current specification provides peel strength of ≥0.8 kN/m.

Smooth Signal Surface

The untreated side has a low surface roughness to help minimize skin-effect-related insertion loss at GHz frequencies. This makes the two-sided surface structure suitable for high-speed transmission applications.

Dynamic Flexibility

The material provides elongation above 20% in the performance description and is specified to withstand more than 150,000 MIT folding cycles without micro-fracturing.

Thermal Stability

The foil is designed to withstand multi-layer lamination at 200–250°C without delamination or blistering under the stated application conditions.

For applications where overall peel strength is the primary requirement rather than a defined single-side surface structure, High-Peel-Strength RA Copper Foil is another related RA copper foil option.

The standard thicknesses listed on the current product specification are 12 μm, 18 μm, and 35 μm. Custom thicknesses from 9–70 μm can be requested according to application requirements.

The manufacturing process begins with high-purity copper melting and casting to produce uniform ingots.

Multi-pass Sendzimir rolling is then used to reduce the material to the required foil thickness. Continuous annealing under a hydrogen atmosphere provides stress relief and controls the recrystallized grain structure.

The surface treatment is applied to one side through electrochemical nodular deposition followed by passivation rinsing. Automated slitting and optical inspection are used to control coil dimensions and surface quality.

Quality Assurance

100% online eddy-current inspection for subsurface voids

Closed-loop hydraulic servo tension control during slitting

Automated edge trimming

Optical surface inspection

Laser-etched coil identification

Mill Test Reports (MTR) covering roughness, tensile properties, and chemical composition

Flexible Printed Circuits

The single-side roughened structure provides a bonding surface for dielectric films while keeping the opposite side smooth. This configuration is suitable for flexible printed circuit construction.

5G Antenna Modules

The combination of controlled bonding roughness and a smooth signal surface can support transmission-line structures where both substrate adhesion and high-frequency signal performance are important.

Automotive Sensor FPCs

The foil can be used in rigid-flex and flexible circuits exposed to thermal cycling and vibration, including automotive sensor assemblies.

Medical Ultrasound Probes

The material is suitable for high-density micro-coaxial and signal-processing flexible boards where compact circuit construction requires controlled copper-to-dielectric bonding.

 The surface structure and dimensions can be adjusted for different circuit and lamination requirements.

Custom Thickness: 9–70 μm available on request.

Roughness Tuning: The treated-side Rz can be adjusted between 1.0 and 2.5 μm according to the selected epoxy, acrylic, or modified polyimide resin system.

Passivation: Anti-tarnish coating options can be tailored for vacuum pressing or direct laser structuring (LDS) processes.

Core Options: 3-inch or 6-inch core inner diameters.

Roll Length: Up to 3,000 meters.

For projects requiring a different surface-treatment configuration, the Treated RA Copper Foil range provides additional options for surface and application requirements.

The product is supplied in suspended wooden crates. Individual coils are wrapped in anti-static VCI film and vacuum-sealed in moisture-barrier bags with desiccant and shock-absorbing foam inserts.

Stock items: 7 business days.

Custom thickness or slitting runs: 15–25 business days.

FOB, CIF, and DDP shipping options are available for air or ocean transportation, with temperature and humidity data loggers used for shipment monitoring.