Fabrication Guidelines CLTE Series Laminates

CLTE Series Laminates Overview

CLTE Series laminates are high-performance ceramic-filled PTFE composites, engineered specifically for high-frequency PCB applications that demand:

• Exceptional electrical performance

• Superior dimensional stability

• Reliable thermal management during fabrication

• Consistent processing across diverse manufacturing environments

These laminates are designed to provide high yield, long-term reliability, and mechanical integrity, making them ideal for RF, microwave, and advanced high-frequency circuits.

Key Considerations for CLTE Laminates

1. Thermal Management

• Designed to withstand repeated thermal cycling, but localized overheating during processing can compromise material properties.

• Always monitor heat during drilling, lamination, and soldering operations to preserve electrical and mechanical performance.

2. Handling Best Practices

• Use non-abrasive handling tools (tweezers, vacuum pick-up, or soft gloves) to prevent contamination, scratches, or delamination.

• Avoid stacking laminates in a manner that can introduce bending stress or creases, which may lead to micro-cracks.

Fabrication Guidelines

1. Storage and Handling

• Store laminates flat in a clean, dry environment:

  • Temperature: 20–25°C (68–77°F)

  • Relative Humidity: <50%

• Avoid bending, twisting, or pressure points on stored laminates.

• Maintain anti-static precautions during handling to prevent ESD damage to high-frequency circuits.

2. Drilling

• Use carbide or diamond-coated drill bits for precision vias and through-holes.

• Match entry and backer materials to laminate hardness to minimize burring and edge breakout.

• Suggested drill speeds:

  • Entry Speed: 150–180 SFM

  • Retract Speed: 350–400 SFM

• Employ peck drilling for deep holes (>1.5× drill diameter) to prevent overheating and reduce clogging.

• Carefully perform deburring to avoid layer separation or material distortion.

3. Lamination

• Precondition the material at 150°C (302°F) for 30–60 minutes to remove residual moisture.

• Recommended press cycle:

  • Temperature: 200–220°C (392–428°F)

  • Pressure: 200–300 psi

  • Time: Hold for 30–60 minutes

• Cool under pressure to avoid void formation or warpage.

4. Etching

• Compatible with standard copper etching solutions.

• Control etching parameters carefully to prevent undercutting, uneven copper removal, or rough edges.

• Rinse and dry laminates thoroughly after etching to maintain surface quality.

5. Plating

• Ensure surfaces are clean and free of contamination before plating.

• CLTE laminates are compatible with electroless and electrolytic copper plating.

• Standard copper plating techniques for multilayer PCBs are suitable.

6. Routing and Cutting

• Use CNC routers with sharp carbide or diamond-coated bits for precise edge profiles.

• Laser cutting is an option for complex shapes, fine features, and quick prototyping.

• Minimize mechanical stress to avoid delamination or micro-cracks along cut edges.

Additional Tips for High-Quality Fabrication

• Bit Maintenance: Replace drill bits every 500–1,000 holes depending on wear and laminate hardness.

• Hole Tolerance: ±0.001 inch to account for thermal expansion and mechanical stress.

• Pilot Holes: For large vias (>0.2 inches), drill pilot holes first to improve accuracy.

• Debris Management: Use vacuum or compressed air to remove particles during drilling to prevent contamination.

• ESD Protection: Essential for high-frequency boards to avoid signal degradation.

Common Challenges and Solutions

Conclusion

Following these comprehensive fabrication guidelines ensures high-quality, high-frequency PCBs with excellent dimensional stability and reliable electrical performance. By adopting best practices in storage, handling, drilling, lamination, etching, plating, and cutting, manufacturers can maximize yield, reduce defects, and enhance long-term reliability of CLTE Series laminates.