The Signal Integrity Problem That Drives Engineers to ITEQ High-Speed Materials
Every PCB engineer who has pushed a design past 10 Gbps has hit the same wall. The board that worked fine at 5 Gbps starts showing eye closure, jitter, and insertion loss failures that simulation didn’t fully predict. You tighten the stack-up, optimize the via transitions, reduce the stub lengths โ and the channel still doesn’t close. Then someone suggests switching the laminate, and suddenly the numbers work.
That experience is what drives engineers toward ITEQ high-speed PCB laminates. The difference between a standard FR-4 with Df of 0.020 and an IT-988GSE with Df of 0.0055 isn’t academic โ at 25 Gbps over a 20-inch backplane trace, it’s the difference between a working channel and a failed one. ITEQ has built one of the most comprehensive high-speed laminate portfolios in the industry, covering everything from the entry-level IT-968 for 10G Ethernet all the way to the IT-908GX for 112G PAM4 and 5G mmWave applications.
This guide covers ITEQ’s complete high-speed laminate portfolio, the signal integrity physics that make material selection matter, how to match the right ITEQ material to your specific design requirements, and how ITEQ stacks up against competing materials from Panasonic, Isola, and Rogers.
Why Laminate Material Determines High-Speed Channel Performance
Before getting into ITEQ’s specific products, it’s worth grounding the discussion in the physics. Understanding why laminate properties matter at high data rates helps you make better material selection decisions and have more productive conversations with your fabricator.
Dielectric Loss: The Primary Insertion Loss Driver Above 5 GHz
Insertion loss in a PCB transmission line has two primary components: conductor loss and dielectric loss. At low frequencies, conductor loss dominates. As frequency increases, dielectric loss grows proportionally with frequency and eventually becomes the dominant loss mechanism.
The dissipation factor (Df, also called loss tangent or tan ฮด) is the material property that directly controls dielectric loss. The relationship is straightforward:
Dielectric loss (dB/inch) โ Df ร frequency ร โDk
This means that at 28 GHz, a material with Df of 0.020 (standard FR-4) has roughly 3.6ร more dielectric loss than a material with Df of 0.0055 (IT-988GSE). Over a 15-inch trace, that difference is the entire loss budget for many high-speed channels.
Dk Stability: Why Frequency-Dependent Permittivity Matters
The dielectric constant (Dk) affects transmission line impedance and signal propagation velocity. What matters for high-speed design isn’t just the Dk value โ it’s how stable that value is across frequency. Standard FR-4 shows significant Dk variation from 1 GHz to 10 GHz (typically 4.6 dropping to 4.3โ4.5). ITEQ’s high-speed materials show much flatter Dk vs. frequency curves, which means your impedance calculations at 1 GHz are still valid at 28 GHz.
Copper Surface Roughness: The Factor That Amplifies Material Differences
Copper surface roughness interacts with laminate loss in a way that many engineers underestimate. At high frequencies, the skin effect confines current flow to the outer surface of the conductor. Rough copper surfaces increase the effective path length of current flow, adding conductor loss that compounds with dielectric loss.
ITEQ’s high-speed materials are specified with different copper foil options:
| Copper Foil Type | Surface Roughness (Rz) | Frequency Range | ITEQ Materials |
| Standard ED | 5โ8 ฮผm | < 5 GHz | IT-158, IT-180A |
| Low Profile (LP) | 3โ5 ฮผm | 5โ15 GHz | IT-968, IT-988GSE |
| Very Low Profile (VLP) | 1.5โ3 ฮผm | 15โ30 GHz | IT-988GSE, IT-998G |
| Ultra Low Profile (HVLP) | < 1.5 ฮผm | > 30 GHz | IT-908G, IT-908GX |
For IT-988GSE and above, specifying VLP copper is not optional for designs above 15 GHz โ the conductor loss contribution from standard copper at those frequencies can exceed the dielectric loss improvement you gained by choosing the better laminate.
Glass Weave Effect and Fiber Weave Skew
Standard glass weave creates periodic variations in the local Dk along a transmission line โ the resin-rich areas between glass bundles have lower Dk than the glass-rich areas. At high data rates, this periodic variation causes differential skew between the two conductors of a differential pair, degrading common-mode rejection and increasing jitter.
ITEQ’s high-speed materials are available with spread-glass weave styles (1078, 1035) that distribute the glass fibers more uniformly, reducing the periodic Dk variation. For designs above 10 Gbps, specifying spread-glass weave is a meaningful signal integrity improvement that costs nothing extra in most cases.
ITEQ High-Speed PCB Laminate Portfolio Overview
ITEQ’s high-speed laminate portfolio spans four performance tiers, each targeting a specific range of data rates and applications. Here’s the complete picture before diving into each tier:
| Performance Tier | ITEQ Products | Df Range (10 GHz) | Target Data Rate | Key Applications |
| Mid-Loss | IT-958G, IT-958GS | 0.0095โ0.0105 | 3โ10 Gbps | USB 3.x, SATA, PCIe Gen 2 |
| Low-Loss Entry | IT-968, IT-968SE | 0.0070โ0.0085 | 6โ25 Gbps | 10G Ethernet, PCIe Gen 3 |
| Low-Loss | IT-988GSE, IT-988GX | 0.0050โ0.0055 | 12โ56 Gbps | PCIe Gen 4, 25G Ethernet |
| Very Low-Loss | IT-998G, IT-998GX | 0.0038โ0.0040 | 28โ56 Gbps | PCIe Gen 5, 56G PAM4 |
| Ultra Low-Loss | IT-908G, IT-908GX | 0.0032โ0.0035 | 56โ112 Gbps | 112G PAM4, 5G mmWave |
Mid-Loss ITEQ High-Speed Laminates: IT-958 Series
IT-958G and IT-958GS: Bridging the Gap from FR-4
The IT-958 series is ITEQ’s answer to the large class of designs that have outgrown standard FR-4 but don’t yet need the full performance of the IT-968 tier. These are halogen-free materials with Tg of 170ยฐC and meaningful loss improvement over standard FR-4.
| Property | IT-958G | IT-958GS | Standard FR-4 | Test Method |
| Tg (DSC) | 170ยฐC | 170ยฐC | 140โ150ยฐC | IPC-TM-650 2.4.25 |
| Td | 340ยฐC | 345ยฐC | 300โ310ยฐC | IPC-TM-650 2.4.24.6 |
| T-288 | 20โ25 min | 22โ28 min | 5โ8 min | IPC-TM-650 2.4.24.6 |
| Dk (1 GHz) | 4.10 | 4.00 | 4.60 | IPC-TM-650 2.5.5.2 |
| Df (1 GHz) | 0.0100 | 0.0090 | 0.0160 | IPC-TM-650 2.5.5.2 |
| Dk (10 GHz) | 3.95 | 3.85 | 4.50 | IPC-TM-650 2.5.5.5 |
| Df (10 GHz) | 0.0105 | 0.0095 | 0.0180 | IPC-TM-650 2.5.5.5 |
| Moisture Absorption | 0.12% | 0.10% | 0.20% | IPC-TM-650 2.6.2.1 |
| CAF Resistance | Good | Good | Marginal | IPC-TM-650 2.6.25 |
| Halogen-Free | Yes | Yes | No | IEC 61249-2-21 |
The IT-958GS with Df of 0.009 at 1 GHz represents roughly a 44% reduction in dielectric loss compared to standard FR-4. For USB 3.1 Gen 2 (10 Gbps) on traces up to 8 inches, this is often sufficient to close the channel without stepping up to IT-968.
When to Choose IT-958 Series
The IT-958 series makes sense when:
Your design runs USB 3.x, SATA 6Gbps, or PCIe Gen 2 with moderate trace lengths
You need halogen-free compliance but can’t justify IT-968 pricing
Your fabricator doesn’t stock IT-968 but has IT-958GS qualified
You’re designing a cost-sensitive industrial product where IT-968 is overkill
The IT-958 series is not the right choice for PCIe Gen 3 or above, 10G Ethernet on traces longer than 6 inches, or any application where you’re running channel simulations and the loss budget is tight.
Low-Loss Entry: IT-968 and IT-968SE
IT-968: The Most Important ITEQ High-Speed Material for Most Engineers
IT-968 is the product that most engineers encounter first when they move beyond standard FR-4 for high-speed designs. It’s widely stocked across Asia, well-characterized by fabricators, and sits at a price point that’s justifiable for a broad range of applications. If you’re designing a board with USB 3.1 Gen 2, 10G Ethernet, or PCIe Gen 3 interfaces and you’re sourcing from an Asian fabricator, IT-968 is almost certainly in your fabricator’s standard stack-up library.
| Property | IT-968 | IT-968SE | Test Method |
| Tg (DSC) | 185ยฐC | 185ยฐC | IPC-TM-650 2.4.25 |
| Td | 350ยฐC | 352ยฐC | IPC-TM-650 2.4.24.6 |
| T-288 | 25โ30 min | 25โ30 min | IPC-TM-650 2.4.24.6 |
| Dk (1 GHz) | 3.90 | 3.85 | IPC-TM-650 2.5.5.2 |
| Df (1 GHz) | 0.0085 | 0.0075 | IPC-TM-650 2.5.5.2 |
| Dk (10 GHz) | 3.85 | 3.80 | IPC-TM-650 2.5.5.5 |
| Df (10 GHz) | 0.0085 | 0.0070 | IPC-TM-650 2.5.5.5 |
| Dk (28 GHz) | 3.78 | 3.72 | Clamped stripline |
| Df (28 GHz) | 0.0095 | 0.0082 | Clamped stripline |
| Moisture Absorption | 0.12% | 0.10% | IPC-TM-650 2.6.2.1 |
| CAF Resistance | Good | Good | IPC-TM-650 2.6.25 |
| Z-CTE | 50 ppm/ยฐC | 50 ppm/ยฐC | IPC-TM-650 2.4.41 |
| Halogen-Free | Yes | Yes | IEC 61249-2-21 |
| Lead-Free Compatible | Yes | Yes | 260ยฐC reflow |
IT-968SE: The Upgrade That Often Closes the Channel
IT-968SE’s Df of 0.007 at 10 GHz puts it at the boundary between mid-loss and low-loss territory. The “SE” designation indicates a reformulated resin system with improved loss characteristics while maintaining the same fabrication process as standard IT-968. Your fabricator doesn’t need to change anything in their process to switch from IT-968 to IT-968SE โ it’s a drop-in upgrade.
For 10G Ethernet designs with trace lengths between 8 and 15 inches, IT-968SE is often the most cost-effective solution that closes the channel budget. The Df improvement from 0.0085 to 0.007 translates to roughly 0.5โ0.8 dB/inch less insertion loss at 10 GHz โ meaningful margin on a long trace.
IT-968 Series Application Mapping
| Application | Interface | Trace Length | IT-968 or IT-968SE? |
| 10G Ethernet NIC | 10GBASE-KR | < 10 inches | IT-968 |
| 10G Ethernet NIC | 10GBASE-KR | > 10 inches | IT-968SE |
| PCIe Gen 3 x16 | 8 Gbps/lane | < 8 inches | IT-968 |
| PCIe Gen 3 x16 | 8 Gbps/lane | > 8 inches | IT-968SE |
| USB 3.1 Gen 2 | 10 Gbps | Any | IT-968 |
| WiFi 6/6E | 5โ6 GHz RF | Any | IT-968 |
| SATA 6Gbps | 6 Gbps | Any | IT-968 |
| 25G Ethernet | 25 Gbps | < 6 inches | IT-968SE |
| 25G Ethernet | 25 Gbps | > 6 inches | IT-988GSE |
Low-Loss ITEQ High-Speed Laminates: IT-988 Series
IT-988GSE: The Workhorse of High-Speed PCB Design in Asia
Ask any PCB engineer at a Taiwanese or Chinese EMS company what laminate they use for PCIe Gen 4 and 25G Ethernet designs, and IT-988GSE comes up in that conversation almost every time. It’s the most widely specified ITEQ high-speed laminate for serious high-speed digital design, and for good reason โ it delivers genuine low-loss performance at a price point that’s accessible for production volumes.
| Property | IT-988GSE | IT-988GX | Test Method |
| Tg (DSC) | 185ยฐC | 185ยฐC | IPC-TM-650 2.4.25 |
| Td | 355ยฐC | 358ยฐC | IPC-TM-650 2.4.24.6 |
| T-288 | 28โ35 min | 30โ38 min | IPC-TM-650 2.4.24.6 |
| Dk (1 GHz) | 3.90 | 3.80 | IPC-TM-650 2.5.5.2 |
| Df (1 GHz) | 0.0060 | 0.0055 | IPC-TM-650 2.5.5.2 |
| Dk (10 GHz) | 3.70 | 3.65 | IPC-TM-650 2.5.5.5 |
| Df (10 GHz) | 0.0055 | 0.0050 | IPC-TM-650 2.5.5.5 |
| Dk (28 GHz) | 3.62 | 3.57 | Clamped stripline |
| Df (28 GHz) | 0.0068 | 0.0062 | Clamped stripline |
| Moisture Absorption | 0.08% | 0.07% | IPC-TM-650 2.6.2.1 |
| CAF Resistance | Very Good | Very Good | IPC-TM-650 2.6.25 |
| Z-CTE | 48 ppm/ยฐC | 47 ppm/ยฐC | IPC-TM-650 2.4.41 |
| Halogen-Free | Yes | Yes | IEC 61249-2-21 |
| Lead-Free Compatible | Yes | Yes | 260ยฐC reflow |
The IT-988GSE’s Df of 0.0055 at 10 GHz represents a 35% improvement over IT-968 and a 70% improvement over standard FR-4. On a 20-inch backplane trace at 25 GHz, that difference is approximately 3โ4 dB of insertion loss โ the difference between a working channel and a failed one.
IT-988GX: When IT-988GSE Isn’t Quite Enough
IT-988GX is the extended-performance variant of IT-988GSE, with Df of 0.005 at 10 GHz vs. 0.0055 for IT-988GSE. The difference sounds small, but on long backplane channels at 25 Gbps, that 0.0005 Df improvement translates to roughly 0.3โ0.5 dB less insertion loss per 10 inches of trace โ meaningful margin when you’re already at the edge of the loss budget.
IT-988GX is the right choice for:
Backplane designs with channel lengths above 20 inches at 25 Gbps
Designs where IT-988GSE simulation shows marginal eye opening
Applications where you want additional margin against manufacturing variation
Hybrid stack-ups where IT-988GX is used on critical signal layers and IT-988GSE on less critical layers
IT-988 Series vs. Competing Low-Loss Materials
| Material | Manufacturer | Dk (10 GHz) | Df (10 GHz) | Relative Cost | Availability in Asia |
| IT-988GSE | ITEQ | 3.70 | 0.0055 | Baseline | Excellent |
| IT-988GX | ITEQ | 3.65 | 0.0050 | +10โ15% | Good |
| Megtron 4 | Panasonic | 3.70 | 0.0060 | +30โ40% | Good |
| FR408HR | Isola | 3.65 | 0.0070 | +15โ25% | Moderate |
| I-Speed | Isola | 3.62 | 0.0060 | +20โ30% | Moderate |
| S7136H | Shengyi | 3.80 | 0.0070 | -10โ15% | Good in China |
| EM-888K | EMC | 3.75 | 0.0065 | -5โ10% | Good in Taiwan |
IT-988GSE is competitive with Megtron 4 on Dk/Df while typically coming in at 30โ40% lower cost when sourced through Asian fabricators. It outperforms Isola FR408HR on loss performance by a meaningful margin.
Very Low-Loss ITEQ High-Speed Laminates: IT-998 Series
IT-998G: ITEQ’s Answer to Panasonic Megtron 6
The IT-998G is where ITEQ’s material science capability really shows. With Df of 0.004 at 10 GHz, IT-998G is directly competitive with Panasonic Megtron 6 โ the material that has been the gold standard for very low-loss PCB design for over a decade. The resin system in IT-998G uses a modified PPO/PPE chemistry that achieves lower moisture absorption and better glass-resin adhesion than standard epoxy, contributing to both the improved electrical performance and the excellent CAF resistance.
| Property | IT-998G | IT-998GX | Megtron 6 (ref) | Test Method |
| Tg (DSC) | 190ยฐC | 195ยฐC | 185ยฐC | IPC-TM-650 2.4.25 |
| Td | 360ยฐC | 362ยฐC | 350ยฐC | IPC-TM-650 2.4.24.6 |
| T-288 | 30โ40 min | 32โ42 min | 30+ min | IPC-TM-650 2.4.24.6 |
| Dk (1 GHz) | 3.60 | 3.55 | 3.61 | IPC-TM-650 2.5.5.2 |
| Df (1 GHz) | 0.0045 | 0.0042 | 0.0040 | IPC-TM-650 2.5.5.2 |
| Dk (10 GHz) | 3.55 | 3.50 | 3.60 | IPC-TM-650 2.5.5.5 |
| Df (10 GHz) | 0.0040 | 0.0038 | 0.0038 | IPC-TM-650 2.5.5.5 |
| Dk (28 GHz) | 3.48 | 3.43 | 3.55 | Clamped stripline |
| Df (28 GHz) | 0.0050 | 0.0046 | 0.0048 | Clamped stripline |
| Moisture Absorption | 0.06% | 0.06% | 0.07% | IPC-TM-650 2.6.2.1 |
| CAF Resistance | Excellent | Excellent | Excellent | IPC-TM-650 2.6.25 |
| Z-CTE | 45 ppm/ยฐC | 44 ppm/ยฐC | 46 ppm/ยฐC | IPC-TM-650 2.4.41 |
| Halogen-Free | Yes | Yes | Yes | IEC 61249-2-21 |
The IT-998G vs. Megtron 6 comparison is one of the most relevant for engineers evaluating supply chain options. On paper, they’re essentially equivalent โ Megtron 6’s Df of 0.0038 vs. IT-998G’s 0.004 is within measurement uncertainty for most test methods. The practical choice often comes down to fabricator qualification status and cost rather than raw material performance.
IT-998GX: The Step Up for 56G PAM4 Backplanes
IT-998GX with Df of 0.0038 at 10 GHz matches Megtron 6’s headline number while maintaining ITEQ’s cost advantage. For 56G PAM4 backplane designs where channel lengths push 24โ30 inches, IT-998GX provides the loss performance needed to close the channel with adequate eye margin.
IT-998 Series Application Mapping
| Application | Data Rate | Channel Length | Recommended |
| PCIe Gen 5 | 32 Gbps/lane | < 12 inches | IT-998G |
| PCIe Gen 5 | 32 Gbps/lane | > 12 inches | IT-998GX |
| 56G PAM4 SerDes | 56 Gbps | < 20 inches | IT-998G |
| 56G PAM4 SerDes | 56 Gbps | > 20 inches | IT-998GX |
| 5G sub-6GHz | 3.5โ6 GHz RF | Any | IT-998G |
| 100G QSFP28 | 25 Gbps/lane | Any | IT-998G |
| 400G QSFP-DD | 56 Gbps/lane | < 15 inches | IT-998G |
| 400G QSFP-DD | 56 Gbps/lane | > 15 inches | IT-998GX |
Ultra Low-Loss ITEQ High-Speed Laminates: IT-908 Series
IT-908G and IT-908GX: ITEQ’s Flagship High-Frequency Materials
The IT-908 series represents ITEQ’s most advanced material technology. These materials use a hydrocarbon-modified resin system that achieves Df values below 0.0035 at 10 GHz while maintaining the thermal reliability (Tg 200ยฐC, T-288 35โ48 minutes) needed for demanding assembly and operating conditions. The IT-908G series is ITEQ’s direct competitor to Panasonic Megtron 7 and Isola Tachyon 100G in the ultra-low-loss tier.
| Property | IT-908G | IT-908GX | Megtron 7 (ref) | Test Method |
| Tg (DSC) | 200ยฐC | 200ยฐC | 195ยฐC | IPC-TM-650 2.4.25 |
| Td | 370ยฐC | 375ยฐC | 365ยฐC | IPC-TM-650 2.4.24.6 |
| T-288 | 35โ45 min | 38โ48 min | 35+ min | IPC-TM-650 2.4.24.6 |
| Dk (1 GHz) | 3.50 | 3.45 | 3.37 | IPC-TM-650 2.5.5.2 |
| Df (1 GHz) | 0.0038 | 0.0035 | 0.0030 | IPC-TM-650 2.5.5.2 |
| Dk (10 GHz) | 3.45 | 3.40 | 3.34 | IPC-TM-650 2.5.5.5 |
| Df (10 GHz) | 0.0035 | 0.0032 | 0.0028 | IPC-TM-650 2.5.5.5 |
| Dk (28 GHz) | 3.38 | 3.33 | 3.28 | Clamped stripline |
| Df (28 GHz) | 0.0042 | 0.0038 | 0.0035 | Clamped stripline |
| Dk (77 GHz) | 3.30 | 3.25 | 3.22 | Split-post resonator |
| Df (77 GHz) | 0.0055 | 0.0050 | 0.0045 | Split-post resonator |
| Moisture Absorption | 0.05% | 0.05% | 0.04% | IPC-TM-650 2.6.2.1 |
| CAF Resistance | Excellent | Excellent | Excellent | IPC-TM-650 2.6.25 |
| Z-CTE | 42 ppm/ยฐC | 40 ppm/ยฐC | 40 ppm/ยฐC | IPC-TM-650 2.4.41 |
| Halogen-Free | Yes | Yes | Yes | IEC 61249-2-21 |
Megtron 7 has a slight edge on Df at 10 GHz (0.0028 vs. 0.0032โ0.0035 for IT-908G/GX), but the gap is smaller than the price difference. For most 112G PAM4 and 5G mmWave applications, IT-908G or IT-908GX provides sufficient performance at a meaningfully lower cost than Megtron 7.
IT-908G for 5G mmWave Applications
The 5G mmWave frequency bands (24โ28 GHz, 37โ40 GHz) place specific demands on PCB laminates that go beyond what standard high-speed digital materials can meet. The key requirements are:
Low Df at 28 GHz: IT-908G’s Df of 0.0042 at 28 GHz is among the best available from any epoxy-based laminate. For antenna array boards and beamforming networks operating at 28 GHz, this translates directly to lower insertion loss and better antenna efficiency.
Stable Dk at 28 GHz: IT-908G shows Dk of 3.38 at 28 GHz vs. 3.45 at 10 GHz โ a variation of only 0.07. This stability is critical for antenna design, where Dk variation directly affects resonant frequency and impedance matching.
Thermal stability: Outdoor 5G base station equipment operates across wide temperature ranges (-40ยฐC to +85ยฐC). IT-908G’s high Tg (200ยฐC) and low moisture absorption (0.05%) ensure that electrical properties remain stable across this temperature range.
IT-908G vs. Rogers RO4350B for 5G mmWave
| Property | IT-908G | Rogers RO4350B | Notes |
| Dk (10 GHz) | 3.45 | 3.48 | Essentially equivalent |
| Df (10 GHz) | 0.0035 | 0.0037 | IT-908G slightly better |
| Dk (28 GHz) | 3.38 | 3.42 | IT-908G slightly lower |
| Df (28 GHz) | 0.0042 | 0.0040 | Rogers slightly better |
| Tg | 200ยฐC | >280ยฐC | Rogers higher |
| T-288 | 35โ45 min | N/A | Different test regime |
| Multilayer capability | Excellent | Limited | IT-908G better for MLB |
| Cost | Moderate | High | IT-908G lower |
| Asian fab availability | Excellent | Moderate | IT-908G better |
For 5G mmWave antenna boards that need to be integrated into multilayer PCB assemblies, IT-908G is often the better practical choice over Rogers RO4350B โ the multilayer fabrication process is more straightforward, and the electrical performance difference at 28 GHz is within the measurement uncertainty of most test setups.
ITEQ High-Speed Laminate Selection by Application Vertical
Data Center and Server Infrastructure
Data center infrastructure is the application vertical where ITEQ high-speed laminates see the most volume. The progression from 10G to 25G to 100G to 400G to 800G networking has driven a corresponding progression through ITEQ’s product line.
| Generation | Switch Speed | Lane Rate | Recommended ITEQ | Stack-Up Notes |
| 10G era | 10G | 10 Gbps | IT-968SE | 8โ10 layer, standard via |
| 25G era | 100G | 25 Gbps | IT-988GSE | 10โ14 layer, back-drill |
| 100G era | 400G | 56 Gbps | IT-998G | 14โ18 layer, back-drill |
| 400G era | 1.6T | 112 Gbps | IT-908G | 16โ20 layer, HDI |
| 800G era | 3.2T | 112 Gbps | IT-908GX | 20+ layer, advanced HDI |