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When designing high-speed multilayer boards, sourcing base materials and customizing the stackup are critical. Get your Panasonic Megtron 6 PCBs or other advanced pcb quote today (consult your dedicated account manager for more material info) to ensure efficient project progression and optimized manufacturing costs.
With the exponential evolution of Artificial Intelligence (AI) computing clusters, 800G/1.6T high-speed data networks, and 5G-Advanced communication technologies, the demands placed on electronic hardware architecture for Signal Integrity (SI) have reached unprecedented heights. Among numerous High-Speed Digital (HSD) laminate materials, Panasonic Megtron 6 consistently holds a crucial position.
Utilizing an advanced hydrocarbon and polyphenylene ether (PPE/PPO) blended resin system, Megtron 6 not only achieves exceptionally low dielectric constant (Dk) and dissipation factor (Df), but more importantly, it boasts excellent process stability for multilayer lamination. Serving as the latest technical guide for 2026, this article provides an in-depth analysis of Megtron 6's core properties and its paramount value in modern PCB design.
Panasonic Corporation Megtron 6 (laminate grade R-5775K and prepreg grade R-5670K) is a PPE-resin-based high-frequency, high-speed PCB material specifically engineered for low-loss digital and RF applications.
Its electrical performance rivals many PTFE-based laminates, while offering significantly better manufacturability, mechanical robustness, and cost efficiency, making it a widely adopted solution for mainstream high-speed multilayer boards.
Below is a detailed summary of the key material characteristics of Megtron 6.
Megtron 6 provides excellent thermal stability and is fully compatible with lead-free assembly processes.
| Property | Test Method | Typical Value |
|---|---|---|
| Glass transition temperature (Tg) | DSC / DMA | 185°C / 210°C |
| Decomposition temperature (Td) | TGA | 410°C |
| Z-axis CTE α1 (< Tg) | IPC-TM-650 | 45 ppm/°C |
| Z-axis CTE α2 (> Tg) | IPC-TM-650 | 260 ppm/°C |
| Time to delamination (T288, with copper) | IPC-TM-650 | > 120 min |
| Thermal conductivity | Laser Flash | 0.4 W/m·K |
These characteristics ensure good dimensional stability, plating reliability, and resistance to thermal stress during multiple reflow cycles.
The core advantage of Megtron 6 lies in its low dielectric constant (Dk) and low loss factor (Df), with stable performance across a wide frequency range.
| Frequency | Dk | Df | Test Method |
|---|---|---|---|
| 1 GHz | 3.71 | 0.002 | IPC-TM-650 2.5.5.9 |
| 2 GHz | 3.40–3.60 | 0.002 | IPC-TM-650 2.5.5.5 |
| 10 GHz | 3.40–3.61 | 0.004 | IPC-TM-650 2.5.5.5 |
| 13 GHz | 3.62 | 0.0046 | Split-post resonator |
Additional electrical parameters:
These properties make Megtron 6 suitable for high-speed backplanes, long trace routing, and low-jitter signal transmission.
| Property | Test Method | Typical Value |
|---|---|---|
| Water absorption | IPC-TM-650 | 0.14% |
| Peel strength (1 oz standard copper) | IPC-TM-650 | 1.2 kN/m |
| Peel strength (1 oz VLP copper) | IPC-TM-650 | 0.8 kN/m |
| Flexural strength | — | 420 MPa |
| Flammability rating | UL 94 | V-0 |
Low moisture absorption and strong copper adhesion contribute to improved reliability in humid or thermally demanding environments.
Megtron 6 is designed not only for electrical performance but also for practical manufacturability in high-layer-count PCB fabrication.
Compared with PTFE materials, Megtron 6 provides easier drilling, lamination, and plating while maintaining comparable signal integrity, which significantly reduces production cost and improves yield.
| Parameter | Condition | Typical Value | Industry Advantage |
|---|---|---|---|
| Dielectric Constant (Dk) | @ 1 GHz - 12 GHz (IPC TM-650) | 3.46 ~ 3.71 | Enables faster signal transmission speeds and lower latency. |
| Dissipation Factor (Df) | @ 1 GHz - 12 GHz | 0.002 | Extremely low signal attenuation, ensuring high-speed eye diagram quality. |
| Glass Transition Temperature (Tg) | DMA / DSC | 210°C (DMA) / 185°C (DSC) | Excellent high-temperature resistance; highly adaptable to lead-free soldering and multiple laminations. |
| Coefficient of Thermal Expansion (Z-axis CTE) | α1 (T < Tg) | 45 ppm/°C | Low Z-axis expansion significantly enhances the reliability of Plated Through Holes (PTH). |
| Peel Strength | H-VLP Copper Foil (1 oz) | 0.7 - 0.8 kN/m | Balances low surface roughness with high adhesion, reducing skin effect losses. |
| Moisture Absorption | D-24/23 | 0.14% | Strong environmental tolerance; electrical performance remains stable in humid environments. |
Note: Actual Dk values will fluctuate slightly depending on the selected glass fiber cloth type (e.g., 1035, 1078, 3313) and resin content (RC%). Specific designs require obtaining the precise impedance stackup structure from your circuit board manufacturer.
Struggling with Impedance Simulation?
Our engineers provide professional stackup optimization using Megtron 6, Megtron 8, and Rogers hybrid materials to ensure ±5% impedance accuracy.
Panasonic Corporation Megtron 8 (main grades such as R-5795U) represents the latest generation of ultra-low-loss multilayer PCB materials, succeeding the Megtron 6 and Megtron 7 platforms. Compared with the Megtron 6 series, Megtron 8 delivers substantial improvements in transmission loss, bandwidth capability, dielectric performance, and thermal reliability, making it purpose-built for next-generation high-speed systems.
Megtron 8 is engineered as an ultra-low transmission loss laminate, targeting some of the lowest signal attenuation levels in the industry.
Loss factor (Df) comparison:
This significant reduction in dielectric loss provides clear advantages for long backplane channels and high-frequency interconnects, enabling cleaner eye diagrams and longer reach without repeaters or retimers.
Megtron 8 was specifically developed to meet the bandwidth demands of hyperscale data centers and next-generation networking equipment.
This performance level makes Megtron 8 a key material for 800G and 1.6T architectures, where insertion loss budgets are extremely tight.
A lower dielectric constant increases signal propagation speed and reduces parasitic capacitance, minimizing latency and dispersion.
In addition to the lower value, Megtron 8 offers tighter phase stability and more consistent dielectric behavior across frequency, delivering RF-class electrical performance while retaining the manufacturability of standard multilayer laminates.
Megtron 8 also improves high-temperature robustness, which is critical for dense server and accelerator platforms.
The higher Tg provides better mechanical strength at elevated temperatures, improved dimensional stability, and greater reliability during assembly and reflow.
Although both materials exceed T288 > 120 minutes, Megtron 8 is optimized for sequential lamination and very high layer counts, making it well suited for complex backplanes exceeding 40 layers.
Megtron 6 typical applications:
Megtron 8 target applications:
Thanks to its superb high-frequency characteristics and FR-4-like manufacturability, Megtron 6 is widely utilized in the following core hardware systems:
In 5G infrastructure, both Panasonic Corporation Megtron 6 and laminates from Rogers Corporation Rogers Corporation are considered leading high-performance materials.
However, they differ significantly in resin systems, design focus, manufacturability, and cost structure. In practice, Megtron 6 is typically optimized for high-speed digital (HSD) multilayer systems, while Rogers materials are more specialized for pure RF and microwave circuits.
The detailed comparison is summarized below.
Megtron 6
Rogers materials
Key difference:
Megtron 6 improves traditional PCB resin chemistry, whereas Rogers often uses ceramic or PTFE-based RF formulations for maximum electrical stability.
Megtron 6 – High-speed digital transmission oriented
Typical uses include:
Advantages:
Rogers – RF/microwave performance oriented
Typical uses include:
Advantages:
Manufacturing convenience
Megtron 6: FR-4-like processing
Rogers:
Mechanical reliability
Megtron 6 features a relatively low Z-axis CTE (~45 ppm/°C), which:
Cost strategy
This approach balances performance and budget.
| Property | Megtron 6 (R-5775K) | Rogers RO4350B | Key Strength |
|---|---|---|---|
| Dielectric constant (Dk) | 3.40–3.61 | 3.48 | Comparable |
| Loss factor (Df) | 0.004 | 0.0031–0.0037 | Slightly lower loss |
| Main advantage | Multilayer stability, HSD balance | Dk stability, precision RF | Different optimization goals |
In short:
When designing high-speed and high-frequency circuit boards with Panasonic Corporation Megtron 6 (grades R-5775K laminate and R-5670K prepreg), engineers should align layout and stack-up decisions with the material’s dielectric, thermal, and mechanical characteristics.
Proper design practices are essential to fully leverage Megtron 6’s low-loss performance while ensuring manufacturability and long-term reliability.
The key considerations are summarized below.
Megtron 6 features a relatively tight dielectric constant tolerance (Dk ≈ ±0.05), which allows more precise impedance prediction than standard FR-4.
Megtron 6 is optimized for 10–25 GHz applications.
For designs exceeding 25 GHz (such as 5G millimeter-wave or advanced radar), higher-performance materials like Megtron 7 or Megtron 8 may be more appropriate.
For typical stack-ups:
To ensure manufacturability and yield, avoid trace widths below 3 mil whenever possible.
All high-speed layers must be adjacent to solid reference planes.
This minimizes return-path discontinuities and EMI.
For signals above 10 GHz, back-drilling is strongly recommended to remove via stubs.
Via stubs can:
Microvias help reduce parasitic inductance and improve routing density.
To minimize skin-effect-related conductor loss at high frequencies (>10 GHz), Megtron 6 should be paired with:
Smoother copper interfaces significantly reduce insertion loss, which is critical for standards such as PCIe Gen5/Gen6.
Since Megtron 6 costs approximately 2–3× standard FR-4, a hybrid design is often recommended:
This balances performance and cost efficiency.
Megtron 6 uses 100% CAF-resistant glass cloth.
To reduce differential skew caused by resin/glass Dk variation:
Megtron 6 has a low Z-axis CTE (~45 ppm/°C), which:
It is fully compatible with lead-free soldering processes.
As a high-Tg, high-performance laminate, Megtron 6 can:
Fabricators should:
This prevents warpage, oxidation, or surface damage.
A complete channel loss budget should be calculated early in the design phase, including:
The total insertion loss must remain within the receiver’s sensitivity margin to ensure reliable system operation.
During the design and fabrication of high-speed PCBs using Panasonic Corporation Megtron 6 (e.g., R-5775K), impedance accuracy is influenced by multiple error sources throughout modeling, materials, manufacturing, and measurement stages.
Even though Megtron 6 provides tight dielectric tolerance and excellent stability, practical impedance variation typically arises from process-related and environmental factors rather than the laminate itself.
These error sources can be grouped into four major categories.
At the simulation stage, impedance prediction accuracy depends heavily on how closely the input parameters reflect real fabrication conditions.
The final laminated dielectric thickness often differs from the nominal stack-up.
Although Megtron 6 has a relatively tight tolerance (±0.05), Dk still shifts with:
If these dependencies are not modeled, impedance predictions may be inaccurate.
Simulation errors occur when models assume ideal rectangular traces.
In reality:
Neglecting these effects results in systematic mismatch between simulated and actual impedance.
Fiber weave effect
Megtron 6 is a glass-fiber/resin composite.
If a trace aligns with glass bundles or resin pockets, the local effective dielectric constant (local Er) fluctuates, causing:
DC resistance impact
In ultra-fine UHDI traces, conductor resistance becomes significant.
During TDR measurements, accumulated resistance produces a rising slope on the impedance curve.
This “upward drift” is sometimes mistakenly attributed to Dk errors, leading to incorrect compensation strategies.
Copper roughness
At high frequencies, copper surface roughness influences:
If the chosen roughness model (e.g., Huray or Gradient) does not match the actual foil type (HVLP or VLP), prediction errors occur.
Etching consistency
Chemical parameters during etching (ORP, acidity, specific gravity, etc.) directly affect final line width.
For high-density routing, even small deviations can lead to:
Process control stability is therefore critical.
Ground plane layout
Using crosshatched or meshed ground planes (common in flexible circuits) complicates impedance control.
Compared with solid reference planes, they:
Solid planes are strongly preferred for high-speed signals.
Test coupon and probe design
Measurement structures introduce their own parasitics.
Potential issues include:
These factors can distort measured impedance.
Environmental interference
External conditions may affect test accuracy:
Even small disturbances can alter high-frequency measurements.
Equipment connections
For Vector Network Analyzer (VNA) or Time Domain Reflectometer (TDR) systems:
are common but often overlooked sources of error.
To minimize impedance uncertainty when using Megtron 6:
By combining accurate modeling, controlled fabrication, and disciplined measurement practices, Megtron 6 can consistently achieve predictable, production-ready impedance performance for high-speed digital designs.
A: No. Megtron 6 employs a high-voltage-resistant resin system paired with 100% CAF-resistant Nittobo glass fiber. It performs exceptionally well in rigorous high-temperature, high-humidity, and biased voltage tests, making it highly suitable for high-density pitch (< 0.8mm) server motherboard applications.
A: Compared to PTFE (Teflon) laminates, which mandate plasma treatment before copper plating, Megtron 6 offers vastly superior processability and is fully compatible with standard FR-4 production lines. However, because it contains specially modified resins, drilling may accelerate drill bit wear and require slight optimization of the desmear chemical parameters. This underlines the importance of partnering with an experienced advanced laminate manufacturer like NextPCB.
A: Absolutely. This is known as an "asymmetrical hybrid stackup." To balance costs, many clients utilize Megtron 6 (R-5775) on critical high-speed routing layers while using conventional high-Tg FR-4 on power/ground layers that don't carry high-speed signals. However, strict attention must be paid to the symmetry of the stackup during design (including CTE matching); otherwise, the board is highly susceptible to severe warpage during wave or reflow soldering.
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