6-Layer Hybrid PCB 1.3mm RO4350B+FR-4 ENEPIG for RF and Digital Systems
1.Introduction
Rogers RO4350B materials are proprietary woven glass reinforced hydrocarbon/ceramics with electrical performance close to PTFE/woven glass and the manufacturability of epoxy/glass.
RO4350B laminates provide tight control on dielectric constant (Dk) and maintain low loss while utilizing the same processing method as standard epoxy/glass. Available at a fraction of the cost of conventional microwave laminates, RO4350B laminates do not require the special through-hole treatments or handling procedures as PTFE based materials. These materials are UL 94 V-0 rated for active devices and high power RF designs.
RO4350B material's thermal coefficient of expansion (CTE) provides several key benefits to the circuit designer. The expansion coefficient of RO4350B material is similar to that of copper which allows the material to exhibit excellent dimensional stability, a property needed for mixed dielectric multi-layer boards constructions. The low Z-axis CTE of RO4350B laminates provides reliable plated through-hole quality, even in severe thermal shock applications. RO4350B material has a Tg of >280°C (536°F) so its expansion characteristics remain stable over the entire range of circuit processing temperatures.
2.Key Features
RO4350B Features:
Stable Dielectric Constant: 3.48 ±0.05 at 10GHz/23°C
Controlled Loss Characteristics: Dissipation Factor of 0.0037 at 10GHz/23°C
Thermal Management: Thermal Conductivity 0.69 W/m/°K
Dimensional Stability: X axis CTE 10 ppm/°C, Y CTE 12 ppm/°C, Z CTE 32 ppm/°C
High Temperature Performance: High Tg value of >280°C
Environmental Resistance: Low water absorption of 0.06%
S1000-2M High Tg FR-4 Features:
Enhanced Reliability: Lower Z-Axis CTE for improved through-hole reliability
Manufacturing Excellence: Excellent Mechanical Processability and Thermal Resistance
Modern Compliance: Lead-free Compatible
Quality Assurance: Tg 180°C (DSC), UV Blocking/AOI compatible
Thermal Performance: High heat resistance
Long-term Reliability: Excellent Anti-CAF performance
Environmental Durability: Low water absorption
3.Benefits
Optimized Performance: Combined RF and digital circuitry in single board
Enhanced Reliability: Excellent dimensional stability for mixed dielectric constructions
Cost-Effective Solution: RF performance at fraction of traditional microwave material cost
Manufacturing Efficiency: Compatible with standard processing methods
Thermal Resilience: Stable performance across wide temperature range
4.PCB Construction Details
| Parameter | Specification |
|---|---|
| Base Material | RO4350B + High Tg FR-4 (S1000-2M) |
| Layer Count | 6-layer |
| Board Dimensions | 30.55mm × 37.7mm = 1PC, ±0.15mm |
| Minimum Trace/Space | 4/4 mils |
| Minimum Hole Size | 0.25mm |
| Blind Vias | L1-L2 |
| Finished Board Thickness | 1.3mm |
| Finished Cu Weight | 1oz (1.4 mils) inner/outer layers |
| Via Plating Thickness | 20 μm |
| Surface Finish | ENEPIG |
| Top Silkscreen | White |
| Bottom Silkscreen | White |
| Top Solder Mask | No |
| Bottom Solder Mask | Green |
| Electrical Test | 100% tested prior to shipment |
5.PCB Stackup (6-Layer Rigid Structure)
| Layer | Material | Thickness |
|---|---|---|
| Copper Layer 1 | Copper | 35 μm |
| Dielectric 1 | RO4350B | 0.102mm (4mil) |
| Copper Layer 2 | Copper | 35 μm |
| Dielectric 2 | Prepreg 1080 RC63% + 7628 (43%) | 0.254mm (10mil) |
| Copper Layer 3 | Copper | 35 μm |
| Dielectric 3 | S1000-2M | 0.254mm (10mil) |
| Copper Layer 4 | Copper | 35 μm |
| Dielectric 4 | Prepreg 1080 RC63% + 7628 (43%) | 0.254mm (10mil) |
| Copper Layer 5 | Copper | 35 μm |
| Dielectric 5 | S1000-2M | 0.254mm (10mil) |
| Copper Layer 6 | Copper | 35 μm |
6.PCB Statistics:
Components: 8
Total Pads: 39
Thru Hole Pads: 21
Top SMT Pads: 12
Bottom SMT Pads: 6
Vias: 23
Nets: 10
7.Typical Applications
Commercial Airline Broadband Antennas
Microstrip and Stripline Circuits
Millimeter Wave Applications
Radar Systems
Guidance Systems
Point to Point Digital Radio Antennas
8.Quality Assurance
Artwork Format: Gerber RS-274-X
Accepted Standard: IPC-Class-2
Availability: Worldwide
