The RO4000® series laminates, including RO4003C™, RO4350B™, and RO4835™, are high-performance materials designed for RF and microwave applications. They combine superior electrical properties with processability similar to traditional FR-4 materials. Below are the recommended fabrication guidelines for achieving optimal performance and reliability.

1. Material Overview

• RO4003C™: Low-loss, glass-reinforced hydrocarbon/ceramic laminate with properties close to PTFE-based materials.
• RO4350B™: Enhanced version with improved thermal stability, suitable for higher power applications.
• RO4835™: Offers improved oxidation resistance for long-term performance in demanding environments.

2. Storage and Handling

• Storage: Store laminates in a controlled environment at 23°C (73°F) and 50% relative humidity.
• Handling: Avoid contamination from oils, fingerprints, or dust. Use clean, dry gloves when handling.

3. Drilling Guidelines

Proper drilling practices are essential to maintain hole quality and minimize defects like burrs or delamination.

• Tool Selection: Use carbide or polycrystalline diamond-coated drills.
• Spindle Speed: 30,000 to 60,000 RPM, depending on hole diameter.
• Feed Rate: 75 to 125 IPM (1.9 to 3.2 m/min). Adjust based on the material and stack height.
• Stacking: Limit the number of boards per stack to maintain drill precision.
• Deburring: Use mechanical or chemical methods to remove burrs without damaging the laminate.

4. Copper Etching

• Etch Compatibility: RO4000 series laminates are compatible with standard copper etching processes.
• Etching Parameters: Optimize etch rates to avoid undercutting or excessive roughness on the copper traces.
• Surface Preparation: Clean thoroughly before and after etching to remove residues.

5. Lamination Process

RO4000 series laminates are compatible with conventional FR-4 processing techniques, but specific parameters are recommended for best results.

• Prepreg Usage: Use compatible Rogers prepreg materials, such as RO4450B™, for multi-layer constructions.
• Lamination Pressure: 250–400 psi (17–28 bar).
• Lamination Temperature: 425–475°F (218–246°C), depending on the prepreg and material type.
• Heating Rate: 3–5°F/min (1.7–2.8°C/min) to prevent delamination or voids.
• Cooling Rate: ≤6°F/min (≤3.3°C/min) under pressure to avoid warping.

6. Solder Mask Application

• Compatibility: Use a solder mask compatible with the RO4000 series surface energy.
• Surface Preparation: Thorough cleaning and micro-etching improve solder mask adhesion.
• Curing: Follow the solder mask manufacturer’s guidelines for curing temperature and time.

7. Plating and Metallization

Ensure robust metallization for reliable electrical connectivity and long-term performance.

• Through-Hole Plating: Use standard electroless copper plating followed by electroplating.
• Plating Thickness: Ensure a minimum copper thickness of 25 µm in through-holes.
• Cleaning: Thoroughly clean drilled holes before plating to remove resin smear.

8. Thermal Management

• Thermal Coefficients: RO4000 laminates have low Z-axis expansion, reducing the risk of via failures during thermal cycling.
• Soldering: Compatible with lead-free and conventional soldering processes. Ensure preheating to minimize thermal shock.

9. Panelization and Routing

• Routing Method: Use carbide tools or laser cutting for edge profiling.
• Tool Speed: 20,000–40,000 RPM for carbide routing.
• Final Finishing: De-burr edges without damaging the laminate.

10. Electrical Testing

• Impedance Control: Validate impedance using time-domain reflectometry (TDR).
• Continuity and Isolation: Perform standard electrical testing for shorts and opens.

11. General Notes

• Environmental Compliance: RO4000 series laminates meet RoHS and REACH standards.
• Documentation: Consult Rogers Corporation technical support for specific application needs or to address unique fabrication challenges.