Rogers RO4000® series laminates, including RO4003C™, RO4350B™, and RO4835™, are widely used in high-frequency applications such as RF, microwave, and millimeter-wave circuits. These laminates offer low dielectric loss, mechanical stability, and compatibility with standard PCB manufacturing processes. The following guidelines provide essential details for fabricating PCBs using these materials.

Material Overview

Property	RO4003C	RO4350B	RO4835
Dielectric Constant (Dk)	3.38 ± 0.05	3.48 ± 0.05	3.48 ± 0.05
Dissipation Factor (Df)	0.0027 at 10 GHz	0.0037 at 10 GHz	0.0037 at 10 GHz
Thermal Conductivity	0.71 W/m·K	0.62 W/m·K	0.66 W/m·K
Moisture Absorption	≤ 0.06%	≤ 0.06%	≤ 0.01%
Flammability	UL 94 V-0	UL 94 V-0	UL 94 V-0

Lamination Guidelines

1. Pre-conditioning

• Pre-bake laminates at 250∘F250^\circ \text{F}250∘F (121°C) for 1–2 hours to eliminate moisture.

2. Lamination Process

• Temperature: Heat to 375–425∘F375–425^\circ \text{F}375–425∘F (190–218°C) depending on copper foil and prepreg type.
• Pressure: Apply 200–300 PSI200–300 \, \text{PSI}200–300PSI (14–21 bar).
• Heating Rate: Maintain 4–8∘F/min4–8^\circ \text{F}/\text{min}4–8∘F/min (2–4°C/min).
• Dwell Time: Hold peak temperature for 30–60 minutes30–60 \, \text{minutes}30–60minutes.

3. Cool Down

• Cool at a controlled rate of <5∘F/min< 5^\circ \text{F}/\text{min}<5∘F/min (3°C/min) to avoid warping.

Drilling Guidelines

1. Drill Bit Type:
   • Use carbide or diamond-coated bits for precision and reduced wear.
2. Drill Parameters:
   • Surface Speed: 350–450 SFM350–450 \, \text{SFM}350–450SFM.
   • Chip Load: 0.001–0.002 in/rev0.001–0.002 \, \text{in/rev}0.001–0.002in/rev.
   • Retract Rate: 500 IPM500 \, \text{IPM}500IPM.
3. Desmear Process:
   • Plasma or sodium etching to clean drilled holes and improve adhesion.

Copper Plating and Etching

1. Surface Preparation

• Use mechanical scrubbing or chemical cleaning to remove oxide and improve adhesion.

2. Plating Process

• Standard electroless and electrolytic plating processes are compatible.
• Thin copper foils may require additional reinforcement during processing.

3. Etching Guidelines

• Use industry-standard etchants.
• Protect fine-line features with photoresist for accuracy.

Surface Finishes

• Compatible with ENIG, immersion silver, immersion tin, and OSP finishes.
• Ensure the selected finish minimizes signal loss and meets environmental requirements.

Handling and Storage

1. Storage Environment:
   • Store laminates flat in a clean, dry area at 20–25∘C20–25^\circ \text{C}20–25∘C (68–77°F) and 50%50\%50% relative humidity.
2. Shelf Life:
   • Use laminates within one year of receipt for optimal performance.
3. Avoid Contamination:
   • Handle with clean gloves to prevent fingerprints or oils from affecting adhesion or electrical properties.

Key Considerations

1. Thermal Management:
   • RO4350B™ and RO4835™ offer better thermal stability than RO4003C™ for applications involving thermal cycling.
2. Fine-Line Features:
   • RO4835™ provides improved etch stability and precision for advanced designs.
3. Environmental Exposure:
   • Low moisture absorption of these laminates ensures stable performance in humid environments.

Applications

• Cellular base station antennas.
• Automotive radar and sensors.
• Satellite communications.
• High-speed digital and mixed-signal circuits.

RO4000® Series laminates, including RO4003C™, RO4350B™, and RO4835™, are high-performance, cost-effective materials for RF and microwave PCB applications. By following these fabrication guidelines, manufacturers can ensure optimal performance and reliability in their high-frequency circuit designs