ITEQ IT-150DA: Halogen-Free Low-Loss PCB Material for High-Speed Design

In the rapidly evolving world of high-speed electronics, the selection of a printed circuit board (PCB) laminate is no longer just a mechanical decision—it is a critical part of the signal integrity chain. As frequencies push toward the millimeter-wave (mmWave) spectrum and automotive safety standards demand unparalleled thermal reliability, the ITEQ IT-150DA material system has emerged as a premier choice for engineers.

ITEQ IT-150DA is a high-Tg (Glass Transition Temperature), halogen-free, and very low-loss laminate designed to meet the rigorous demands of next-generation applications. From automotive radar systems to high-end computing, this material offers a unique balance of environmental compliance and “ultra-stable” electrical performance. Unlike standard FR4, which acts like a “speed bump” for high-frequency signals, IT-150DA provides a clear, low-attenuation pathway that ensures data reaches its destination with minimal jitter and distortion.

This engineering guide dives deep into the technical specifications, fabrication nuances, and design strategies for ITEQ IT-150DA, providing a comprehensive roadmap for its successful deployment.

The Material Science of ITEQ IT-150DA

To appreciate the value of IT-150DA, we must look at its core chemistry. Most low-cost laminates utilize a dicyandiamide (DICY) curing system, which is prone to moisture absorption and thermal breakdown. ITEQ IT-150DA, however, is built on an advanced resin technology that is both phenolic-cured and filled with inorganic silica.

This formulation achieves three critical engineering goals:

Halogen-Free Compliance: It meets the strictest environmental “Green” standards (like IEC 61249-2-21) without the brittleness common in older halogen-free materials.

Thermal Stability: With a Tg of 180°C (DSC), it remains mechanically rigid far beyond the operating temperatures of standard electronics.

Low Dielectric Loss: By optimizing the resin-to-glass interface, ITEQ has achieved a Dissipation Factor (Df) of <0.007 at 10GHz, putting it in the “very low loss” category required for high-speed SerDes and radar applications.

Technical Specifications: The ITEQ IT-150DA Datasheet

For a PCB layout engineer, the datasheet is the source of truth. When running simulations in tools like ADS or HyperLynx, the accuracy of your Dk/Df data determines the success of your first prototype.

Thermal and Mechanical Performance Table

Property	Test Method	Typical Value	Unit
Glass Transition Temp (Tg)	IPC 2.4.25 (DSC)	180	°C
Decomposition Temp (Td, 5% loss)	IPC 2.4.24.6	370	°C
Z-Axis CTE (Alpha 1, < Tg)	IPC 2.4.24	45	ppm/°C
Z-Axis CTE (Alpha 2, > Tg)	IPC 2.4.24	250	ppm/°C
Total Z-Axis Expansion (50-260°C)	IPC 2.4.24	2.6	%
Moisture Absorption	IPC 2.6.2.1	< 0.10	%
Thermal Resistance (T288)	IPC 2.4.24.1	> 30	Minutes

Electrical Integrity Parameters (at 50% Resin Content)

One of the standout features of IT-150DA is the stability of its Dielectric Constant (Dk) across the frequency spectrum. This “flatness” is essential for broadband signals where phase distortion must be minimized.

Frequency	Dielectric Constant (Dk)	Dissipation Factor (Df)
1 GHz	3.73	0.0052
2 GHz	3.71	0.0053
5 GHz	3.69	0.0057
10 GHz	3.64	0.0065

Signal Integrity and High-Speed Design Strategy

Designing with a low-loss material like ITEQ IT-150DA requires a different mindset than standard FR4. Because the material itself is so transparent to signals, other design factors—like copper roughness and via transitions—become the dominant sources of loss.

Managing Copper Foil Roughness

High-frequency signals travel on the “skin” of the copper trace due to the skin effect. If the copper surface is rough (like standard HTE foil), the signal travels a longer path, increasing resistive loss. ITEQ IT-150DA is compatible with Very Low Profile (VLP) and Reverse Treat Foil (RTF). When specifying your stackup, choosing VLP copper with IT-150DA can reduce insertion loss by as much as 20% at 28Gbps or higher.

Via Reliability and Z-Axis Stability

High-speed designs often involve high layer counts (12+ layers) and dense via arrays. During lead-free reflow, the board expands. If the Z-axis CTE of the material is too high, it will stretch and eventually crack the copper plating inside the via barrels. IT-150DA’s total Z-expansion is limited to 2.6%, which is significantly lower than the 3.5%–4.5% seen in standard materials. This makes it an ideal candidate for boards with thick profiles and small-diameter vias.

Why Halogen-Free Matters in Modern Engineering

The “Halogen-Free” (HF) designation in IT-150DA is not just for marketing; it is a critical technical requirement for global markets. Halogens (Chlorine and Bromine) are effective flame retardants but release toxic, corrosive gases if the board burns.

Beyond environmental safety, the phosphorus-based flame retardants used in HF materials like IT-150DA often result in better thermal decomposition (Td) and lower moisture absorption. IT-150DA’s Td of 370°C is world-class, allowing it to survive multiple lead-free reflow cycles or aggressive wave soldering without delamination.

Fabrication and DFM Guidelines for ITEQ IT-150DA

While IT-150DA is designed to be “FR4-friendly,” it is a high-performance material that requires specific manufacturing controls to maintain high yields.

Drilling and Desmear

The silica fillers used in IT-150DA are abrasive. To ensure clean, smear-free holes:

Drill Parameters: Spindle speeds and feed rates must be optimized to prevent resin smear. If the drill bit is too hot, the resin melts and coats the inner-layer copper, causing intermittent opens.

Chemical Desmear: The desmear line must be properly balanced. Because IT-150DA is chemically robust, it may require a slightly more aggressive permanganate cycle or a plasma desmear for high-reliability applications.

Lamination Press Cycle

To achieve a void-free board with consistent thickness:

Heating Rate: A controlled ramp rate of 1.5°C to 3.0°C per minute is recommended.

Pressure: High pressure (300-400 psi) ensures the resin flows adequately to fill the gaps between traces, especially in designs with 2oz or 3oz copper.

Cure Time: Minimum of 60 minutes at >185°C to ensure 100% molecular cross-linking.

Comparing IT-150DA to Other ITEQ Materials

ITEQ offers a broad portfolio. Understanding where IT-150DA fits in the hierarchy is key to cost-optimization.

Material	Class	Tg (DSC)	Df @ 10GHz	Target Application
IT-150G	Mid-Tg HF	150°C	~0.014	Consumer Electronics
IT-150GS	Mid-Tg HF	155°C	~0.012	Servers & Storage
IT-180A	High-Tg	180°C	~0.013	Automotive / Industrial
IT-150DA	Very Low Loss	180°C	<0.007	Radar / High-Speed Digital

As you can see, IT-150DA is the “specialist” in this group—offering the thermal stability of a flagship High-Tg material with the electrical performance typically reserved for high-speed networking gear.

Key Applications of ITEQ IT-150DA

Where should you specify this material? It is most effective in designs where both thermal endurance and signal integrity are non-negotiable.

Automotive Radar (24GHz / 77GHz): The ultra-stable Dk/Df performance makes it perfect for radar sensors that must operate reliably from -40°C to +125°C.

High-Speed Computing: Server motherboards and line cards running 25G, 56G, or 112G SerDes channels.

Electric Vehicle (EV) Systems: Battery management systems (BMS) and power modules that require high-Tg survival and moisture resistance.

Telecom & 5G: Base station components and high-frequency antennas requiring halogen-free compliance for global deployment.

Useful Resources and Procurement Links

To ensure your design is manufacturable and your data is current, use the following resources:

Official Datasheets: Always download the latest revision to check for updates in Dk/Df tolerance.

UL Product iQ: Verify the UL 94 V-0 flame rating for file number E178114.

Fabrication Experts: For specialized high-speed builds and stackup validation using this material, you can find expert technical support and material sourcing at ITEQ PCB.

IPC-4101 standards: Cross-reference Slash Sheets /128 for halogen-free performance requirements.

Frequently Asked Questions (FAQs)

1. Is ITEQ IT-150DA suitable for hybrid stackups?

Yes. Many engineers use IT-150DA for the high-speed outer layers and a cheaper high-Tg material (like IT-180) for the internal power/ground layers. This “Hybrid Stackup” balances performance and cost.

2. How does IT-150DA handle moisture?

With a moisture absorption rate of <0.10%, it is exceptionally robust. This is critical for automotive and aerospace applications where humidity can cause impedance shifts in other materials.

3. Does this material require a specialized surface finish?

While compatible with ENIG and HASL, high-speed designs (especially 77GHz radar) often benefit from Immersion Silver or Immersion Tin to minimize the “Nickel Loss” associated with ENIG at high frequencies.

4. Why is the Dk so low (3.64 @ 10GHz) compared to standard FR4?

The combination of low-Dk glass and advanced resin allows the material to achieve this. A lower Dk allows for wider trace widths for a target 50-ohm impedance, which reduces resistive losses.

5. Is IT-150DA compatible with laser drilling?

Yes. The silica filler is fine-grained, allowing for consistent laser ablation. It is a preferred choice for HDI (High-Density Interconnect) designs requiring blind and buried microvias.

Conclusion: Elevating Design with IT-150DA

The ITEQ IT-150DA stands as a testament to the fact that environmental responsibility and high-performance engineering are not mutually exclusive. By providing a very low-loss dielectric with the thermal backbone of an 180°C Tg material, it gives engineers the confidence to design complex, high-speed systems that are ready for the global market.

Whether you are routing the next-generation automotive safety sensor or a high-capacity data center switch, specifying IT-150DA ensures your board will be as reliable as it is fast.