RT/duroid® alternative alternative? TLY-5 Laminate PCB – Lower Loss, Higher Yields for 77GHz Radar and Avionics

Product Description

What is TLY-5?
TLY-5 is an avionics and aerospace-grade, very low dielectric constant (Dk) base material manufactured by AGC. It features a lightweight woven fiberglass reinforcement that provides superior dimensional stability compared to chopped fiber reinforced PTFE composites. With an ultra-low dissipation factor of 0.0009 at 10GHz, a Dk of 2.20 ± 0.02, and excellent mechanical properties, TLY-5 is purpose-built for millimeter-wave applications up to and beyond 77GHz, including automotive radar, satellite communications, and aerospace systems.

 

Key Takeaways (At a Glance)

 

Dk (10GHz): 2.20 ± 0.02 (specifiable from 2.17 to 2.40)

 

Dissipation Factor: 0.0009 @ 10GHz – the lowest in its class

 

CTE (X/Y/Z): 26 / 15 / 217 ppm/°C (25–260°C)

 

Thermal Conductivity: 0.22 W/(m·K)

 

Moisture Absorption: 0.02% – exceptionally low

 

Flammability: UL 94 V-0

 

NASA Outgassing: TML, CVCM, WVR all ≤ 0.01%

 

Key Differentiator: Lightweight woven glass reinforcement offers superior dimensional stability over chopped fiber alternatives, enabling higher manufacturing yields

 

 

1. Why Choose TLY-5? – Material Selection Rationale

For engineers designing high-frequency circuits at millimeter-wave frequencies (Ka, E, W bands), material selection is critical to achieving both electrical performance and manufacturability. TLY-5 addresses these demands through four key advantages:

 

Ultra-Low Dielectric Loss: With a dissipation factor of 0.0009 at 10GHz, TLY-5 delivers the lowest Df in its class. This translates to minimal insertion loss—a critical factor for 77GHz automotive radar and other millimeter-wave antenna applications where signal attenuation must be tightly controlled.

 

Superior Dimensional Stability: Unlike chopped fiber reinforced PTFE composites, TLY-5 uses a lightweight woven fiberglass matrix. This yields a mechanically stable laminate that resists dimensional changes during PCB fabrication, resulting in higher manufacturing yields and consistent performance across high-volume production runs.

 

Consistent & Uniform Dk: The dielectric constant can be specified within a range of 2.17 to 2.40, with a tight tolerance of ±0.02 for most thicknesses. This uniformity ensures predictable impedance control and phase response—essential for phased-array antennas and beamforming networks.

 

Aerospace-Grade Reliability: With NASA outgassing values (TML, CVCM, WVR) all at ≤0.01% and UL 94 V-0 flammability rating, TLY-5 meets the stringent requirements for spaceborne and avionics applications.

 

 

2. Properties of TLY-5 Laminate

The table below consolidates all electrical, mechanical, thermal, and physical specifications for TLY-5 as provided in the official datasheet. All values represent typical measured data and are intended to aid in material selection.

Property	Conditions	Typical Value	Units	Test Method
Dielectric Constant	@ 10 GHz	2.2	—	IPC-650 2.5.5.5
Dissipation Factor	@ 10 GHz	0.0009	—	IPC-650 2.5.5.5
Volume Resistivity	After elevated temp.	10¹⁰	Mohms/cm	IPC-650 2.5.17.1
Volume Resistivity	After humidity	10¹⁰	Mohms/cm	IPC-650 2.5.17.1
Surface Resistivity	After elevated temp.	10⁸	Mohms	IPC-650 2.5.17.1
Surface Resistivity	After humidity	10⁸	Mohms	IPC-650 2.5.17.1
Thermal Conductivity	—	0.22	W/(m·K)	ASTM F 433
CTE – X-axis (25–260°C)	—	26	ppm/°C	ASTM D 3386 (TMA)
CTE – Y-axis (25–260°C)	—	15	ppm/°C	ASTM D 3386 (TMA)
CTE – Z-axis (25–260°C)	—	217	ppm/°C	ASTM D 3386 (TMA)
Peel Strength	1/2 oz. ED copper	1.96 (11)	N/mm (lbs/in)	IPC-650 2.4.8
Peel Strength	1 oz. CL1 copper	2.86 (16)	N/mm (lbs/in)	IPC-650 2.4.8
Peel Strength	1 oz. C1 copper	3.04 (17)	N/mm (lbs/in)	IPC-650 2.4.8
Peel Strength (elevated temp.)	—	2.32 (13)	N/mm (lbs/in)	IPC-650 2.4.8
Flexural Strength – MD	—	96.91 (14,057)	N/mm² (psi)	IPC-650 2.4.4
Flexural Strength – CD	—	89.32 (12,955)	N/mm² (psi)	IPC-650 2.4.4
Young's Modulus – MD	—	9.65 × 10³ (1.4 × 10⁶)	N/mm² (psi)	ASTM D 3039 / IPC-650 2.4.19
Poisson's Ratio – MD	—	0.21	—	ASTM D 3039 / IPC-650 2.4.19
Density (Specific Gravity)	—	2.19	g/cm³	ASTM D 792
Dimensional Stability – MD	10 mil, avg. after bake & thermal stress	-0.038	mm/M (mils/in)	IPC-650 2.4.39
Dimensional Stability – CD	10 mil, avg. after bake & thermal stress	-0.038	mm/M (mils/in)	IPC-650 2.4.39
Moisture Absorption	—	0.02	%	IPC-650 2.6.2.1
NASA Outgassing – TML	—	0.01	%	—
NASA Outgassing – CVCM	—	0.01	%	—
NASA Outgassing – WVR	—	0.01	%	—
Flammability Rating	—	V-0	—	UL-94

Notes:

Dielectric constant can be specified within a range of 2.17 to 2.40 with a tolerance of ±0.02 for most thicknesses.

 

 

3. Available Thicknesses & Panel Sizes

 

Standard Thicknesses:

0.0035" (0.09 mm)

0.0050" (0.13 mm)

0.0075" (0.19 mm)

0.0100" (0.25 mm)

0.0200" (0.51 mm)

0.0300" (0.76 mm)

0.0600" (1.52 mm)

TLY-5 can be manufactured in increments of 0.005" (0.125 mm). Additional thicknesses available upon request.

 

 

Standard Panel Sizes:

12" × 18" (305 × 457 mm)

16" × 18" (406 × 457 mm)

18" × 24" (457 × 610 mm) – Standard panel size

16" × 36" (406 × 914 mm)

24" × 36" (610 × 914 mm)

18" × 48" (457 × 1220 mm)

 

 

4. PCB Design Case Study – From Specification to Reality

To illustrate how TLY-5 performs in a real-world design, here is a 2-layer board example featuring a 0.3mm finished thickness.

 

 

PCB Design Specifications

Parameter	Specification
Base Material	TLY-5
Layer Count	2
Board Dimensions	45mm × 87mm (±0.15mm)
Finished Board Thickness	0.3mm
PCB Stackup	Cu (35μm) / TLY-5 (0.191mm / 7.5mil) / Cu (35μm)
Minimum Trace / Space	6 / 10 mils
Minimum Hole Size	0.4mm
Blind Vias	None
Finished Copper Weight (Outer Layers)	1oz (35μm / 1.4 mils)
Via Plating Thickness	20 μm
Surface Finish	EPIG (Electroless Palladium Immersion Gold)
Top Silkscreen	None
Bottom Silkscreen	None
Top Solder Mask	None
Bottom Solder Mask	None
Quality Standard	IPC Class-2
Testing	100% Electrical Test
Artwork Format	Gerber RS-274-X
Availability	Worldwide

 

 

Engineering Rationale for Key Specifications:

Parameter	Rationale
TLY-5 Selection	Chosen for ultra-low Df (0.0009), consistent Dk (2.20 ± 0.02), and dimensional stability—critical for millimeter-wave performance and high-volume manufacturing yield.
0.3mm Finished Thickness	Achieved using 7.5mil (0.191mm) TLY-5 core; supports compact, weight-sensitive designs while maintaining mechanical rigidity.
6/10 mils Trace/Space	Standard wet etching capability; accommodates both RF and DC routing requirements.
0.4mm Minimum Hole Size	Mechanical drilling is straightforward; no laser or blind vias required, simplifying fabrication and reducing cost.
1oz Copper Weight	Balances current-carrying capacity with fine-feature etching capability.
20 μm Via Plating	Exceeds IPC Class-2 minimum; ensures robust PTH reliability.
EPIG Surface Finish	Electroless Palladium Immersion Gold provides excellent flatness, oxidation resistance, and wire bondability—ideal for high-frequency assemblies.
No Solder Mask / No Silkscreen	Eliminates potential RF interference; simplifies processing for this high-frequency design.
IPC Class-2	Balances cost and reliability for commercial aerospace and telecom applications.
100% Electrical Test	Ensures impedance, continuity, and isolation before shipment.

 

 

Key Fabrication Notes for TLY-5:

 

Drilling: TLY-5's woven fiberglass construction requires sharp carbide drills with optimized speeds and retract rates. While the lightweight glass reinforcement reduces tool wear compared to standard FR-4, proper parameters are essential to prevent burrs and ensure clean hole walls.

 

Surface Preparation: For EPIG or other finishes, standard PTFE surface preparation techniques apply. Plasma treatment may be beneficial for ensuring strong plating adhesion.

 

Dimensional Stability: The woven glass matrix provides excellent dimensional stability during processing, resulting in tighter registration and higher yields compared to chopped fiber alternatives. This is particularly valuable for designs with dense via fields (139 vias in this case) and fine-pitch components.

 

 

5. TLY-3FF: The Flexible Variant

For applications requiring bend radius flexibility, AGC offers TLY-3FF, a highly flexible laminate designed for flexible or rigid-flex circuits. Key differentiators include:

 

Flexibility comparable to chopped fiber reinforced PTFE laminates

 

Lower loss tangent than traditional chopped fiber reinforced laminates

 

Improved laser via formation capability

 

Retains the dimensional stability of standard TLY-5 Series

 

This makes TLY-3FF an excellent choice for wearable electronics, foldable antennas, and applications where mechanical bending is required without sacrificing RF performance.

 

 

6. Comparative Positioning – How TLY-5 Stands Out

Compared to typical chopped fiber reinforced PTFE composites, TLY-5 offers several distinct advantages:

Aspect	TLY-5 (Woven Glass)	Chopped Fiber PTFE
Dimensional Stability	Superior – woven matrix provides mechanical rigidity	Lower – can shift during processing
Manufacturing Yield	Higher – consistent panel-to-panel	Lower – more variation
Dissipation Factor	0.0009 (lowest in class)	Typically higher
Dk Tolerance	±0.02 (tight control)	Wider variation
Machining / Drilling	Good – lightweight glass	More difficult – abrasive fibers
Flexibility	Standard	More flexible (but TLY-3FF addresses this)

 

 

7. Typical Applications – Where TLY-5 Shines

Based on its property set and the design case above, TLY-5 is well-suited for:

 

Automotive Radar: 77GHz and 79GHz sensors for ADAS and autonomous driving systems

 

Satellite & Cellular Communications: Ka-band terminals, ground station equipment

 

Power Amplifiers: High-frequency RF power stages requiring low loss

 

LNBs, LNAs, LNCs: Low-noise blocks and amplifiers for satellite reception

 

Aerospace & Avionics: Radar altimeters, communication systems, navigation equipment

 

Ka, E, and W Band Applications: Millimeter-wave systems up to and beyond 77GHz

 

 

Q1: What is the dielectric constant range for TLY-5?

The Dk can be specified within a range of 2.17 to 2.40. For most thicknesses, the tolerance is ±0.02, providing excellent consistency for impedance-controlled designs.

 

 

Q2: How does TLY-5 compare to chopped fiber reinforced PTFE composites?
TLY-5 uses a lightweight woven fiberglass matrix, offering superior dimensional stability and higher manufacturing yields. At 77GHz, comparative testing has shown "drop-in" equivalent insertion loss performance, with the primary benefit being improved processability.

 

 

Q3: What is the maximum operating frequency for TLY-5?
TLY-5 is successfully deployed in applications up to 77GHz (automotive radar) and beyond, including Ka, E, and W bands. Its ultra-low Df (0.0009) makes it suitable for millimeter-wave frequencies.

 

 

Q4: Is TLY-5 suitable for space applications?
Yes. With NASA outgassing values (TML, CVCM, WVR) all at ≤0.01% and UL 94 V-0 flammability, TLY-5 meets aerospace-grade requirements for spaceborne and avionics equipment.

 

 

Q5: What is the difference between TLY-5 and TLY-3FF?
TLY-3FF is a highly flexible variant of TLY-5, designed for applications requiring bend radius. It offers flexibility comparable to chopped fiber laminates while maintaining lower loss and improved laser via formation capability.

 

 

Q6: What copper weights and finishes are available?
Standard copper options include 1/2 oz and 1 oz, with various treatments (ED, CL1, C1). Surface finishes include EPIG (as in the design case), as well as other standard options upon request.

 

 

Q7: Are all values in the property table guaranteed?
The data provided are typical measured values intended to aid in material selection. They do not constitute specification values. For critical tolerances, please contact AGC directly.

 

 

Q8: What panel sizes are available for TLY-5?
Standard panel sizes range from 12" × 18" to 24" × 36", with the standard being 18" × 24" (457 × 610 mm). Additional sizes are available upon request.

 

 

Conclusion

TLY-5 from AGC represents a compelling solution for engineers designing high-frequency, millimeter-wave circuits that demand ultra-low loss, consistent dielectric properties, and exceptional dimensional stability. As demonstrated by the 2-layer PCB design case—featuring a 0.3mm thickness, 139 vias, and EPIG surface finish—TLY-5 integrates smoothly into standard fabrication workflows while delivering the electrical performance required for 77GHz automotive radar, satellite communications, and aerospace applications. With its lightweight woven glass reinforcement, TLY-5 not only matches the electrical performance of chopped fiber alternatives but surpasses them in manufacturability and yield—making it a reliable, field-proven choice for high-volume millimeter-wave production.