The Origin of the M Series: Panasonic MEGTRON's Technical Hegemony

The "M Series" nomenclature was not established by international standards organizations (such as IPC); its roots point directly to Panasonic. In the 1990s, as data processing volumes surged, traditional FR-4 materials could no longer meet the signal integrity requirements for high frequencies. Leveraging its advanced resin modification technology, Panasonic launched the MEGTRON brand series. The name, a portmanteau of "Mega" and "Electron," signifies an electronic material born to handle mega-level high-frequency signals. Panasonic's brilliance lay in its clear generational product mapping: Starting from M2 and M4 as entry-level high-speed materials, progressing to M6 and M7 tailored for the explosion of data centers and AI servers, moving up to M8 designed for next-generation 112G PAM4 and beyond, and finally reaching the flagship M9 featuring Q-glass (Quartz cloth) technology.

Every increase in the "M number" corresponds to a lower Dissipation Factor (Df), a more stable Dielectric Constant (Dk), and higher thermal resistance. When computing giants like NVIDIA explicitly adopted the "Panasonic M9 + Q-glass + HVLP copper foil" solution as the "standard answer" for high-frequency, high-speed PCBs in their next-generation AI server architectures (such as the Rubin architecture), this coding system became deeply embedded in the component selection logic of the entire tech supply chain.

Why Are There No M1, M3, and M5? The Truth Behind Skipping to M6

From a technical evolution standpoint, the early M2 and M4 already qualified as high-speed materials. So why are M1, M3, and M5 missing? This gap is actually the result of both technical progression and commercial strategy.

Simply put: M1, M3, and M5 never existed in the market. The M6 we know today is actually a new starting point after Panasonic reorganized its product line to align with the demands of the high-speed digital age.

1. M2 and M4 Were Indeed Early High-Speed Materials

M2 and M4 are early Panasonic products classified as entry-level and mid-to-high-speed materials, distinct from standard FR-4.

• M2 (MEGTRON-2): Launched around 2000, with a Df ≈ 0.005. Designed for early 10Gbps servers and 4G base stations, it was the industry's first widely adopted "entry-level high-speed" material.
• M4 (MEGTRON-4/4S): Introduced around 2005–2008, with a Df ≈ 0.003–0.004. Designed for 25Gbps mid-to-high-speed scenarios, it was the mainstream high-speed substrate of the 10G/25G era.

2. Why Skip the Odd Numbers?

Panasonic's MEGTRON naming convention is not sequential but follows an internal strategy of "performance generations + even-number priority":

1. No M1: The MEGTRON series started with M2. The earliest generation of high-speed materials was positioned as "mid-loss" and subsequently upgraded directly to M2 (low loss). M1 was never developed.
2. No M3, M5: Following the even-number iteration rule (M2 → M4 → M6 → M8), a higher number signifies lower loss and higher supported speeds, without creating intermediate odd-numbered sub-categories.

Note: The subsequent appearance of M7 and M9 was actually driven by extreme market and client demands for hyper-segmentation. M7 filled the gap between M6 and M8, while M9 represents the absolute pinnacle above M8.

3. Why the Direct Jump to M6 / M7 / M8 / M9?

The core reason lies in the explosion of transmission rates and the step-function leap in performance:

• M6: Designed for 56Gbps+, Df ≈ 0.002–0.0025. It defined "very low loss" and became the benchmark for 400G front-haul and early AI servers.
• M7: Bridges the gap between M6 and M8 (Df ≈ 0.0018–0.002), designed for 112G PAM4.
• M8: Df ≈ 0.0012–0.0015, supporting 224G+. It is the core material for current mainstream AI servers.
• M9: Utilizes Q-glass + M9 resin + HVLP copper foil, Df < 0.0013. Designated for NVIDIA's Rubin architecture, it defines the current "industry ceiling."

Will there be an M10 level material in the future? Absolutely. As 6G and Co-Packaged Optics (CPO) technologies advance, material limits will continue to be broken.

Is the "Q-glass" in M9 the Same as "Quartz Cloth"?

Yes, Q-glass is Quartz Cloth.

• Q = Quartz
• Q-glass = Quartz cloth

This is a fiberglass cloth woven from fibers drawn from high-purity quartz, specifically applied to ultra-high-end, ultra-low-loss high-speed PCB boards. Compared to standard fiberglass or Low Dk (LD-glass) fiberglass, Q-glass boasts a lower and much more stable Dk value, alongside an extremely low Df value. This minimizes signal distortion under ultra-high-frequency, long-link transmissions. Top-tier computing boards like NVIDIA's GB200 must utilize Q-glass specifications.

A Quick Guide to Industrial Cloth Classifications:

• Standard Boards: Standard fiberglass cloth (E-glass)
• High-Speed Boards: Low loss fiberglass cloth (LD-glass / Low Dk)
• Ultra-High-Speed / AI Boards: Q-glass (Quartz cloth)

Why Did Panasonic's Codes Become the Industry's "Weights and Measures"?

First, Panasonic defined a remarkably clear roadmap for technological evolution. While the rest of the industry was still using vague terms like "low loss" or "ultra-low loss," Panasonic directly correlated the numerical differences of M6 and M8 with distinct speed grades.

Second, the explosion of AI computing power turned the M series into a de facto performance benchmark. Once NVIDIA confirmed its use of M9-grade solutions, the entire supply chain had no choice but to align with this standard. To enter the top-tier supply chain, CCL manufacturers across Taiwan and Mainland China aggressively launched products benchmarking the performance of M6, M7, and M8. Over time, the "M numbers" shed their single-brand trademark status and evolved into the "universal language" used globally by the PCB industry to describe high-speed material grades.

Benchmarking Reference Table for Major Asian CCL Manufacturers:

| Equivalent Grade | Panasonic Standard | Dissipation Factor Df (@10GHz) | Representative Asian Mfrs (Partial) | Mfr Corresponding Series (Ref) | | :--- | :--- | :--- | :--- | :--- | | Low-to-Mid Loss | M6 | 0.003 ~ 0.004 | Shengyi / Nanya / Huazheng | S7439 / NE-VL / H5 | | Ultra-Low Loss | M7 | 0.002 ~ 0.0025 | EMC / Shengyi / Nanya | EM-892 / S8939 / NE-VL | | Extreme-Low Loss | M8 | 0.0015 ~ 0.0018 | Shengyi / Nanya / Huazheng | S1G / NE-VLL / HSD8 | | Supreme Ultra-Low Loss | M9 (Q-glass) | 0.0009 ~ 0.0013 | Shengyi / Nanya / Huazheng / Dongcai | S10939 / NE-VLL(Q) / HSD9Q / DT-M9 |

Note: Brand specifications and formulas, such as hydrocarbon resin + Q-glass technologies, are continuously updated. Specific values should be verified against the latest Data Sheets from the respective manufacturers.

As the saying goes, "There is no path in the world, but when many people walk it, a path is formed." A company with robust technical capabilities that gains widespread recognition from top-tier clients naturally becomes the rule-maker and the industry benchmark.

Professional Support from eCloud

Whether you are developing high-frequency communication modules or designing hardware for next-generation AI servers, eCloud provides the most professional PCB prototyping and manufacturing services. From economical M6-grade high-speed solutions to the ultimate M9 + Q-glass top-tier processes, we have extensive material reserves and engineering expertise to help bring your projects to life rapidly. Feel free to contact our engineering team anytime for the latest material selection advice!