ITEQ IT988GSE: UltraLow Loss with LowDk Glass for 112 Gbps Applications

In the modern era of 112 Gbps+ SerDes and PAM4 data rates, standard FR4 PCB materials no longer deliver adequate signal integrity. Engineers rely on extremely low dielectric constants and ultralow dissipation factors to minimize insertion loss and channel attenuation across highspeed channels. ITEQ IT988GSE is an advanced highperformance, halogenfree laminate designed around lowDk glass and optimized resin systems to enable nextgeneration data rates and highfrequency performance. 合美新PCB+1

This article will cover:

What ITEQ IT988GSE is and why it matters

Detailed electrical, thermal, and mechanical properties

Practical design considerations for 112 Gbps PCB designs

Application case studies

A comparison with alternatives

Useful resources & datasheets

5 engineering FAQs

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Table of Contents

Introduction

What Is ITEQ IT988GSE?

Key Material Properties

Electrical Characteristics

Thermal and Mechanical Performance

Benefits of LowDk Glass in HighSpeed Design

PCB Stackup & Design Considerations

Typical Applications

Comparison With Other Substrates

Useful Resources

FAQs

Conclusion

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1. Introduction

When channel data rates push beyond 56 Gbps per lane into 112 Gbps and beyond, electrical characteristics of the PCB substrate become dominant factors in determining system reliability. From insertion loss to impedance stability and skew control, every percentage of performance counts. Against this backdrop, engineers increasingly turn to advanced materials like ITEQ IT988GSE that are engineered from the ground up for demanding highfrequency applications. 聯茂電子股份有限公司

Whether you are designing 112 Gbps SerDes channels, PAM4 PAM2 systems, or mmWave RF/5G front ends, understanding substrate behavior is essential to meeting your performance margins.

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2. What Is ITEQ IT988GSE?

ITEQ IT988GSE is an ultralow loss, halogenfree laminate and prepreg substrate engineered with lowDk glass and advanced highTg resin technology. It was introduced as an enhanced version of the IT988 series with a specialized glass cloth weave that reduces dielectric constant (Dk) and dissipation factor (Df) relative to standard highspeed PCBs. 聯茂電子股份有限公司

Unlike conventional FR4 or even earlier highspeed laminates, IT988GSE targets:

Highspeed digital data channels (>56 Gbps per channel)

Reduced skew across differential pairs

Stable performance at Nyquist frequencies up to and beyond ~28 GHz

Hybrid RF + digital designs

By combining low Dk and low Df with high thermal reliability and low CTE, IT988GSE delivers predictable, repeatable performance across process, thermal, and environmental variations — a must for nextgeneration PCB designs. 聯茂電子股份有限公司

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3. Key Material Properties

To design around 112 Gbps signals, engineers focus on dielectric behavior and thermal reliability. Below is how IT988GSE performs according to IPCTM650 and supplier datasheet specifications:

Electrical Characteristics (Typical)

Property	Value	Units	Notes
Dielectric Constant (Dk)	~3.01	—	@10 GHz, 70 % resin 聯茂電子股份有限公司
Dissipation Factor (Df)	~0.0022	—	@10 GHz, 70 % resin 聯茂電子股份有限公司
Moisture Absorption	~0.26 %	%	Typical low hygroscopic behavior 合美新PCB
Volume Resistivity	~4×10¹⁶	MΩ·cm	Excellent insulation 合美新PCB
Surface Resistivity	~1.37×10¹²	Ω	High surface insulation 合美新PCB

Why these matter:

Lower Dk improves signal propagation speed and reduces capacitive loading — critical at >112 Gbps.

Lower Df reduces energy loss per unit length, preserving eye amplitude and reducing power budget for equalization.

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Thermal and Mechanical Performance

Property	Typical Value	Unit	Rationale
Glass Transition Temp (Tg)	~180 °C	°C	Supports leadfree assembly 聯茂電子股份有限公司
Decomposition Temp (Td)	~400 °C	°C	Similar to advanced PCB substrates 聯茂電子股份有限公司
CTE (X/Y)	~35–45	ppm/°C	Good dimensional stability 聯茂電子股份有限公司
Zaxis CTE	~2–3 % (50–260 °C)	%	Low vertical expansion 聯茂電子股份有限公司
Thermal Stress Resistance	Pass	IPC Standard	High reflow tolerance 合美新PCB

High Tg and Td increase tolerance to soldering and thermal cycling. Low CTE reduces stress on throughholes and vias — crucial for highlayer count boards. Together, these parameters improve manufacturability and reduce reliability risk over life. 聯茂電子股份有限公司

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4. Benefits of LowDk Glass in HighSpeed Design

In advanced PCB materials, glass cloth choice matters. IT988GSE uses lowDk glass that significantly lowers the overall dielectric constant while minimizing the glass fiber weave effect. This woven effect can cause impedance variation and skew in differential pairs because each fiber bundle locally alters Dk. 聯茂電子股份有限公司

Key benefits of lowDk glass include:

Reduced skew between highspeed differential traces

Lower impedance variation across multilayer stackups

Improved insertion loss in highfrequency channels

Better control of return loss and reflection

This makes IT988GSE particularly valuable in designs where tight impedance tolerance and minimal Sparameter degradation are nonnegotiable.

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5. PCB Stackup & Design Considerations

For designers implementing 112 Gbps channels, effective stackup planning is mandatory:

Controlled Impedance and Transmission Lines

Trace Environment	Target Impedance	Notes
Microstrip (outer)	50 Ω	Ground reference immediately below
Stripline (inner)	85 Ω	For differential pairs
Differential Pair	100 Ω	Highspeed SerDes routes

Engineering Tip: Use simulation tools (Polar, Saturn PCB Toolkit, HyperLynx) with accurate Dk/Df values at your target frequency — not just the datasheet @1 GHz — for accurate impedance modeling.

Via, HDI, and Signal Integrity

Low permittivity and controlled CTE help with:

Microvia formation and reliability

Reduced via stubs and reflections

Hybrid RF + digital performance

Ensure board fabrication partners can handle multiple reflows and fine HDI structures reliably.

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6. Typical Applications

ITEQ IT988GSE finds use wherever loss budgets are tight and performance margins small:

Application Category	Why Engineers Use IT988GSE
112 Gbps SerDes interconnects	Signal integrity across long PCB runs
AI/HPC fabrics & switch backplanes	Extremely low insertion loss
5G/6G Infrastructure	High Dk stability at RF/mmWave bands
Automotive Radar & ADAS	Thermal and reliability robustness
Highspeed optical modules	Controlled dielectric performance

Beyond data communication, the material also performs well in mixed RF + digital circuits due to its stable dielectric behavior and low energy loss.

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7. Comparison With Other Substrates

Material	Dk @10 GHz	Df @10 GHz	HalogenFree	Applications
ITEQ IT988GSE	~3.0	~0.0022	Yes	112 Gbps+ designs
ITEQ IT988G	~3.2–3.4	~0.0025+	Yes	56112 Gbps class 信号完整性期刊+1
Standard FR4	~4.2	~0.02	Varies	Lowspeed designs

From a highspeed engineering perspective, ITEQ IT988GSE’s lower Dk and Df relative to IT988G provide measurable benefit at higher frequency and greater data rates — especially in designs where the Nyquist of 112 Gbps PAM4 approaches ~28 GHz.

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8. Useful Resources

Resource	Type	Link
ITEQ PCB Materials Overview	Manufacturer portfolio	https://www.pcbsync.com/ITEQ-pcb/
IT988GSE Datasheet (Engineered copy)	Technical parameters	[Product PDF listings via PCB suppliers] 合美新PCB
IPCTM650 Test Methods	Industry test methods	IPCStandards subscription
Impedance & SI Tools	Software calculators	Polar Instruments / Saturn PCB Toolkit
Highspeed Design Guides	Technical best practices	Mentor/Siemens, Cadence SI resources

Engineering Tip: Always request lotspecific characterization data from your laminate supplier for stackup simulations and manufacturing signoff.

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9. FAQs

1. Why choose IT988GSE over IT988G?

IT988GSE uses lowDk glass to further reduce dielectric constant and dissipation factor, enabling lower insertion loss at higher frequencies — important for 112 Gbps designs. 聯茂電子股份有限公司

2. What makes lowDk glass beneficial for signal integrity?

LowDk glass reduces dielectric loading and minimizes skew and impedance variation caused by fiber weave effects in the laminate. 聯茂電子股份有限公司

3. Can IT988GSE handle multiple SMT reflows?

Yes — the high Tg (~180 °C) and low CTE characteristics support leadfree processes and thermal cycling in complex assemblies. 聯茂電子股份有限公司

4. Is IT988GSE suitable for RF/mmWave as well as digital?

Yes — its low loss and stable Dk/Df make it viable for hybrid RF + digital systems where signal integrity matters up into mmWave bands. 聯茂電子股份有限公司

5. How do I validate stackup performance with IT988GSE?

Use precise Dk/Df frequencyspecific values from your fab partner and verify controlled impedance targets with test coupons and SI simulations.

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10. Conclusion

ITEQ IT988GSE represents a strategic choice for engineers pushing the limits of highspeed PCB design. Its combination of low dielectric constant, ultralow loss, stable thermal behavior, and halogenfree composition makes it wellsuited for 112 Gbps and higher data rate applications across networking, telecom, automotive, and HPC platforms. With controlled impedance and predictable performance, IT988GSE helps designers hit critical signal integrity margins while managing manufacturability and reliability.