What Are M9 Materials? Understanding the Circuit-Board Materials Upgrade Behind AI Servers

AI servers usually bring compute chips and memory to mind first. But these components also need circuit boards to exchange large volumes of signals. As transmission speeds increase, board materials must improve as well. The growing interest in “M9” is part of this upgrade in high-speed circuit-board materials.

When Panasonic publicly introduced MEGTRON9 in 2025, it positioned the material for 224 Gbps transmission per lane—approximately 224 billion bits per second. ITEQ's related materials target similar speeds and applications in next-generation networking equipment, servers, and backplanes. The common requirement is to preserve sufficiently clear signals as large amounts of data travel through the board. [1][3]

Understanding M9 starts with distinguishing CCL from PCB. Copper-clad laminate (CCL) is a base material used to manufacture circuit boards. A typical CCL contains resin, glass-fiber cloth, and copper foil; some formulations also include fillers. Manufacturers turn the copper foil into circuits and use lamination, drilling, metallization, and other processes to produce a printed circuit board (PCB) on which electronic components can be mounted. [2][9]

Each constituent has a different role:

Board performance therefore depends on more than the copper traces. The insulating materials around the conductors also affect signal propagation and the energy lost in transmission. [2]

Two common figures in a materials datasheet are Dk and Df. Dk, the dielectric constant, relates to signal propagation speed and impedance design. Df, the dissipation factor, describes the degree to which a material dissipates energy in an alternating electric field. At the same frequency and under the same test conditions, a lower Df generally means lower dielectric loss. Actual transmission-line loss, however, also depends on the copper foil and circuit geometry. A single Df value cannot determine the performance of the entire board. [9]

M9-generation materials aim to reduce these losses in faster applications. The name M9 does not reveal a complete formulation: meaningful product comparisons still require the supplier's part number, constituent materials, and measurement conditions.

Public products already show different glass-fiber combinations. ITEQ's IT-999GSE2 uses second-generation low-dielectric-constant glass cloth, or Low-Dk2 glass. IT-999GSE3 uses Q-glass, commonly called quartz cloth. Both target 224 Gbps applications, demonstrating that different material combinations can improve transmission capability. [3]

Quartz cloth attracts attention because of its low dielectric loss and low thermal expansion. Shin-Etsu's published data for SQX quartz cloth, for example, gives a Df of 0.0001 at 10 GHz and describes thermal expansion at approximately one-tenth that of conventional glass cloth. These properties can help high-speed laminates reduce dielectric loss and maintain dimensional stability. [4]

Glass cloth is only one constituent, however. A low Df for a raw material does not mean a finished CCL will retain the same value. Resin, fillers, constituent ratios, and processing jointly determine finished-product performance.

Another approach attracting attention is polytetrafluoroethylene (PTFE). Its low dielectric loss makes it suitable as the resin matrix of a circuit substrate. In its 2025 annual report, TAIFLEX disclosed a Df of 0.0006 at 10 GHz for its PTFE-based CCL and claimed better performance than existing M9 materials at that time. [6]

That disclosure illustrates the electrical potential of PTFE, but the report did not provide a complete list of comparison products and board structures. It cannot establish that every PTFE material outperforms every other option. PTFE and quartz cloth also belong to different material categories: the former can serve as a resin matrix, while the latter is a reinforcing fiber. Their names do not define mutually exclusive alternatives.

Low-loss materials also need appropriate copper foil. ITEQ's published IT-999GSE3 specifications list low-roughness foils such as HVLP4/HVLP5. Smoother conductor surfaces help reduce high-frequency transmission loss, but surface treatment must also ensure a strong bond between copper and insulation. Electrical performance and adhesion must therefore be considered together. [5][8]

This is a central difficulty in M9 development: reducing loss while keeping the material consistently processable in a PCB factory.

Quartz-fiber processing and cost challenges have long been discussed in public research. A Hitachi Chemical patent identified production-efficiency, cost, and drillability problems with quartz cloth and proposed reducing fiber content as one improvement. This helps explain why simply substituting quartz cloth does not complete an upgrade, but it cannot be used to estimate current prices or yields. [7]

More recent research indicates that drilling is not the only issue. A public Qnity abstract on M9 quartz-fiber materials notes increased drill wear and lower surface reactivity, making electroless copper coverage and bonding on hole walls more difficult. PCB holes require reliable conductive metal on their walls to connect circuits on different layers. Hole preparation and metallization quality therefore directly affect circuit reliability. [8]

The abstract also describes approaches to improving hole-wall treatment and electroless copper processing. It is publicly available on the IMPACT-IAAC 2026 website, but the conference is scheduled for October 2026. Its description of the challenges and research direction can be cited at this stage; detailed validation conditions still require the full paper. [8]

High-layer-count boards impose further demands. A board contains many circuit layers, and some structures are built in stages with repeated lamination, drilling, and metallization. Through these processes and subsequent soldering heat cycles, the material must preserve interlayer adhesion, dimensions, and the integrity of its via structures. [9]

“Heat resistance” in a materials specification must therefore be read together with the test conditions. For IT-999GSE3, the supplier lists T288 greater than 60 minutes, indicating resistance to delamination under the specified 288°C test conditions. This is a material-level indicator. A real high-layer-count board also involves board thickness, layer count, the number of lamination cycles, moisture condition, and via design. Validation must use the relevant structure. [5][9][10]

Reducing signal loss, passing a thermal test on a material coupon, and achieving stable production in a particular multilayer, sequential-lamination design are different levels of evidence. Public specifications show what a material can do; whole-board qualification determines where it can be used.

For general readers, three questions help track M9's progress: Are signals transmitted better? Can factories process the material consistently? Is the completed board reliable? As AI and high-speed networking equipment demand more data throughput, the most important value of this materials generation is bringing low-loss performance into circuit boards that can be manufactured repeatedly and used reliably over time.