12-Layer Hybrid PCB – RO4350B + RO3010 ENEPIG High Frequency Multilayer

1. Introduction to Hybrid RO4350B+RO3010 PCB

This 12-layer hybrid rigid PCB combines Rogers RO4350B hydrocarbon ceramic laminate and RO3010 ceramic-filled PTFE composite, bonded with RO4450F prepreg. The design features top and bottom 4mil RO4350B layers with middle RO3010 cores of 5mil, 10mil, and 25mil thicknesses, offering a unique mixed-dielectric solution for high-frequency and microwave applications requiring different dielectric constants within a single board.

RO4350B provides Dk 3.48±0.05 and low loss (Df 0.0037@10GHz) with standard FR-4 processing, while RO3010 offers Dk 10.2±0.3 for high dielectric constant requirements. This hybrid construction enables optimized impedance control and signal integrity in complex RF designs.

2. Key Features

• 12-layer hybrid construction: RO4350B (top/bottom 4mil) + RO3010 (5/10/25mil cores) + RO4450F prepreg

• RO4350B: Dk 3.48±0.05 @ 10GHz, Df 0.0037 @ 10GHz, Tg >280°C

• RO3010: Dk 10.2±0.3 @ 10GHz, Df 0.0023 @ 10GHz, Tg >280°C

• ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold) – Nickel-free palladium gold finish

• Green solder mask both sides, white silkscreen both sides

• Blind via structures: 1-2, 2-5, 2-6, 2-8, 1-9, 10-12, 3-12

• Board dimensions: 107mm x 91.5mm, 2PCS per panel

• Finished board thickness: 3.14mm

3. Benefits

• Mixed dielectric design enables optimized performance across frequency bands

• RO4350B provides low loss and consistent Dk for high-frequency signal paths

• RO3010 offers high Dk for compact component integration and antenna applications

• ENEPIG finish ensures excellent solderability, wire bondability, and corrosion resistance without nickel concerns

• Blind via technology enables high-density interconnect (HDI) routing

• RO4450F prepreg provides reliable bonding between dissimilar materials

• Standard FR-4 processing compatibility for cost-effective fabrication

4. PCB Construction Details

5. PCB Stackup (12-Layer Hybrid Structure)

Layer 1 (Top Copper) – 35 μm (1 oz)

RO4350B – 0.102 mm (4mil)

Layer 2 (Cu. free) – RO4450F – 0.102 mm

Layer 3 (Copper) – 18 μm (0.5 oz)

RO3010 – 0.254 mm (10mil)

Layer 4 (Copper) – 18 μm (0.5 oz)

RO4450F – 0.102 mm

Layer 5 (Copper) – 18 μm (0.5 oz)

RO3010 – 0.254 mm (10mil)

Layer 6 (Cu. free) – RO4450F – 0.102 mm

Layer 7 (Copper) – 18 μm (0.5 oz)

RO3010 – 0.635 mm (25mil)

Layer 8 (Copper) – 18 μm (0.5 oz)

RO4450F – 0.102 mm

Layer 9 (Cu. free) – RO3010 – 0.127 mm (5mil)

Layer 10 (Copper) – 18 μm (0.5 oz)

RO4450F – 0.102 mm

Layer 11 (Copper) – 18 μm (0.5 oz)

RO3010 – 0.254 mm (10mil)

Layer 12 (Copper) – 18 μm (0.5 oz)

RO4450F – 0.102 mm

Layer 13 (Cu. free) – RO3010 – 0.254 mm (10mil)

Layer 14 (Cu. free) – RO4450F – 0.102 mm

Layer 15 (Copper) – 18 μm (0.5 oz)

RO3010 – 0.127 mm (5mil)

Layer 16 (Copper) – 18 μm (0.5 oz)

RO4450F – 0.102 mm

Layer 17 (Copper) – 18 μm (0.5 oz)

RO4350B – 0.102 mm (4mil)

Layer 18 (Bottom Copper) – 35 μm (1 oz)

Total pressed thickness: 3.14mm

6. PCB Statistics

Components: 38

Total Pads: 124

Thru Hole Pads: 52

Top SMT Pads: 72

Bottom SMT Pads: 0

Vias: 96 (including blind vias)

Nets: 3

7. Blind Via Structures

8. RO4350B High Frequency Circuit Materials

RO4000® hydrocarbon ceramic laminates are designed to offer superior high frequency performance and low cost circuit fabrication. The result is a low loss material which can be fabricated using standard epoxy/glass (FR-4) processes offered at competitive prices.

RO4350B laminates feature Dk 3.48±0.05, Df 0.0037@10GHz, Tg >280°C, and CTE matched to copper (10/12/32 ppm/°C). The material's thermal coefficient of expansion provides excellent dimensional stability and reliable plated through-hole quality.

9. RO3010 High Frequency Circuit Materials

RO3000® series high frequency circuit materials are ceramic-filled PTFE composites intended for use in commercial microwave and RF applications. RO3010 laminates offer a high dielectric constant of 10.2±0.3 at 10GHz, with low dissipation factor of 0.0023.

RO3010 materials exhibit CTE matched to copper (16/16/24 ppm/°C) and provide excellent dimensional stability and reliable plated through-hole performance, making them ideal for antenna and high-frequency component applications.

10. Material Properties Summary

11. Primary Application Areas

• RF and microwave circuits requiring mixed dielectric constants

• Patch antennas and antenna arrays

• Power amplifiers and matching networks

• Filters, couplers, and combiners

• Automotive radar and ADAS systems

• Satellite communication equipment

• Wireless infrastructure (5G base stations)

12. Quality Assurance

• Type of artwork supplied: Gerber RS-274-X

• Accepted standard: IPC-Class-2

• Availability: Worldwide

• 100% Electrical test prior to shipment

• Blind via reliability verified per IPC-6012