1. Introduction
ITEQ IT-968 is a high-performance laminate and prepreg material designed for high-speed digital and high-frequency PCB applications. Engineered for ultra-low loss, high glass transition temperature (Tg), and lead-free assembly compatibility, IT-968 is ideal for advanced electronic systems such as 100G/400G switches, high-speed servers, telecommunications equipment, RF/microwave circuits, and automotive radar systems.
ITEQ IT-968 combines excellent electrical performance with robust mechanical and thermal properties, providing PCB manufacturers with a reliable substrate for demanding applications.
2. Material Properties Overview
| Property | Typical Value | Test Method |
|---|---|---|
| Dielectric Constant (Dk) @ 10 GHz | ~3.66 | IPC-TM-650 |
| Dissipation Factor (Df) @ 10 GHz | ~0.0050 | IPC-TM-650 |
| Glass Transition Temperature (Tg) | ~185°C | DSC |
| Coefficient of Thermal Expansion (CTE) | X/Y: 12/14 ppm/°C; Z: Alpha1 45 ppm/°C, Alpha2 260 ppm/°C | IPC-TM-650 |
| Thermal Decomposition (Td) | ~400°C | TGA |
| Flammability | UL94 V-0 | Standard Test |
| Mechanical Strength | Excellent | IPC-TM-650 |
| Moisture Absorption | <0.1% | IPC-TM-650 |
Key Features:
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High Tg: Stable under high-temperature lead-free soldering processes.
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Ultra-Low Loss: Maintains signal integrity at high frequencies.
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Thermal and Mechanical Reliability: Resistant to thermal stress and environmental conditions.
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Process Compatibility: Suitable for multilayer, through-hole, and surface mount assemblies.
3. Applications
ITEQ IT-968 is suitable for a wide range of high-performance electronics applications:
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High-Speed Digital Circuits: Servers, storage systems, and 100G/400G switch solutions.
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Telecommunications: Routing and switching equipment, base stations, and high-frequency communication devices.
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RF and Microwave Circuits: Antennas, wireless systems, and radar applications.
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Automotive Electronics: ADAS, engine control units, infotainment systems, and radar modules.
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Aerospace and Defense: Avionics, satellites, military communications, and radar systems.
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Industrial Electronics: Automation controllers, robotics, and power electronics.
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Consumer Electronics: Smartphones, laptops, gaming devices, and wearables.
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Medical Devices: Diagnostic and monitoring equipment requiring precision and reliability.
4. PCB Stack-Up and Design Considerations
To fully leverage IT-968’s performance, careful PCB stack-up design is essential:
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Layer Count: Based on signal complexity and space constraints.
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Signal Integrity: High-speed traces on inner layers; controlled impedance routing.
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Power/Ground Planes: Minimize EMI and maintain voltage stability.
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Layer Arrangement: Alternating signal and ground layers reduces crosstalk.
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Dielectric Layer Selection: Optimize for impedance and signal performance.
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Copper Weight & Thickness: Adjust for mechanical and electrical requirements.
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Via Design: Use through-hole, blind, or buried vias depending on density.
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Thermal Management: Implement thermal vias or heat sinks as needed.
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Manufacturability: Ensure compatibility with drilling, lamination, and plating processes.
5. Fabrication Guidelines
5.1 Drilling
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Tool Selection: Use carbide or twist drills optimized for ceramic-filled laminates.
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Speed & Feed: 150,000–200,000 RPM; 2–3 mil/rev; retract 500–600 IPM.
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Hole Preparation: Plasma desmear or chemical cleaning for clean PTH surfaces.
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Cooling: Use water-soluble oil or PCB coolant to prevent heat buildup.
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Deburring: Remove sharp edges to avoid signal reflection or soldering issues.
5.2 Lamination
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Prepreg: RO4450F™ recommended for multilayer boards.
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Temperature & Pressure: 425–450°F (220–230°C), 200–400 psi, dwell 60 min.
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Uniform Pressure: Prevent warping or delamination.
5.3 Etching
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Standard copper etching suitable, but tight controls required for fine-pitch RF circuits.
5.4 Solder Mask & Surface Finish
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Use solder masks compatible with high-frequency laminates.
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Surface finishes include ENIG, immersion tin/silver, or OSP.
5.5 Soldering
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Lead-free compatible; follow controlled reflow profiles below Tg (~185°C) to prevent delamination.
5.6 Testing & Quality Control
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Electrical: Impedance, frequency response, signal integrity testing.
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Visual: Inspect for etching defects, delamination, or misaligned components.
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Environmental: Thermal cycling and humidity tests for reliability assurance.
6. Comparison with Other PCB Substrates
| Feature | IT-968 | Typical FR-4 | Other High-Speed Laminates |
|---|---|---|---|
| Dk Stability | Excellent | Moderate | Varies |
| Dissipation Factor | Ultra-low (0.005) | Higher | Similar or lower |
| Tg | ~185°C | 130–140°C | 150–200°C |
| Mechanical Strength | High | Moderate | High |
| Lead-Free Compatibility | Yes | Limited | Yes |
| Cost | Moderate | Low | Higher |
Summary: IT-968 provides an optimal balance between high-frequency performance, thermal reliability, mechanical strength, and cost, making it ideal for modern high-speed, high-frequency PCB, and RF PCB applications.
7. Best Practices
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Store laminates in a cool, dry environment to avoid moisture absorption.
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Test fabrication processes on sample boards before full production.
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Use precise drilling and lamination techniques for dimensional stability.
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Avoid bending or excessive mechanical stress.
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Incorporate thermal vias or heatsinks in high-power applications.
8. Conclusion
ITEQ IT-968 is a high-performance PCB substrate material designed for applications requiring high-speed digital performance, RF/microwave reliability, and robust thermal stability. Its ultra-low loss characteristics, high Tg, and lead-free compatibility make it an ideal choice for telecommunications, automotive, aerospace, industrial, and consumer electronics applications.
By carefully designing the stack-up, controlling fabrication parameters, and applying proper testing procedures, PCB manufacturers can leverage IT-968 to achieve high-quality, reliable, and high-performance electronic circuits.
