TF440 Ceramic-Filled PTFE Laminate and Custom 2-layer rigid PCB built on 25mil substrate with immersion gold

Product Description

Not every high-frequency application requires the mechanical reinforcement of woven glass. For circuits where precise dielectric constant control, low loss, and high reliability are paramount, ceramic-filled PTFE laminates without glass fabric offer a compelling alternative. The TF440 from Taizhou Wangling Insulation Materials Factory is a prime example: a PTFE-ceramic composite engineered for microwave and millimeter-wave circuits requiring stable electrical performance and long-term thermal reliability.

The TF series is composed of polytetrafluoroethylene (PTFE) resin with excellent microwave properties and temperature resistance, combined with ceramic fillers. Crucially, the material contains no woven glass fabric. By adjusting the ratio of ceramic to PTFE resin, the dielectric constant can be precisely controlled. Manufactured with a special process, the TF series offers outstanding dielectric performance and high reliability. The TF440 variant delivers a Dk of 4.4 ± 0.09 at 10 GHz with a dissipation factor of just 0.001.

In the TF series naming convention, TF refers to unclad smooth material, TF-1 refers to single-sided copper clad, and TF-2 refers to double-sided copper clad.

Key Properties at a Glance (TF440):

Applications

1. Microwave and Millimeter-Wave Circuits – Filters, couplers, and matching networks
2. Aerospace Equipment – Space and cabin systems requiring radiation resistance and low outgassing
3. Phased Array and Phase-Sensitive Antennas – Stable Dk for precise phase control
4. RF Front-End Modules – Low-loss signal paths for sensitive receivers
5. Low-Noise Amplifiers (LNAs) – Minimal dielectric loss for improved noise figure
6. Satellite Communication Systems – Reliable performance in space environments
7. High-Reliability RF Passive Components – Power dividers, combiners, and couplers

Custom PCB Manufacturing on TF440

As a specialized manufacturer of high-frequency printed circuit boards, we offer comprehensive fabrication services using TF440 and other advanced materials. The following specification details a representative 2-layer rigid PCB implementation:

PCB Construction Details:

The TF series allows precise adjustment of Dk by varying the ceramic-to-PTFE ratio. TF440 offers a Dk of 4.4 ± 0.09 (±2%) at 10 GHz, enabling accurate impedance control and repeatable circuit performance. The broader TF series covers Dk values from 3 to 16, with common values at 3.0, 6.0, 9.2, 9.6, 10.2, and 16.

A dissipation factor of 0.0010 at 10 GHz ensures minimal signal attenuation, making TF440 ideal for low-noise amplifiers, sensitive receive paths, and high-performance passive components.

The absence of woven glass fabric eliminates glass weave effects that can cause impedance variations and skew in high-speed and high-frequency circuits. This contributes to more uniform electrical performance across the board.

The dielectric constant temperature coefficient of -60 ppm/°C over -55°C to +150°C provides stable performance across temperature. The material's long-term operating temperature range of -80°C to +200°C exceeds that of TP materials, making it suitable for demanding thermal environments.

TF440 offers radiation resistance and low outgassing properties, making it suitable for space and cabin equipment. Its high reliability supports mission-critical applications in satellite communications and aerospace systems.

At ≤0.05%, TF440 absorbs minimal moisture, maintaining stable electrical properties in humid environments.

The material can be processed following standard thermoplastic material methods, simplifying fabrication compared to some alternative high-frequency substrates.

The demonstrated PCB implementation includes copper filling vias on designated IC pads, providing improved thermal dissipation for high-power components.

Quality and Availability

All boards are manufactured in compliance with IPC-Class-2 quality standards, ensuring robust reliability for commercial, industrial, and aerospace applications. 100% electrical testing is performed prior to shipment to guarantee functional integrity.

Our production capability extends to worldwide availability, with flexible shipping and logistics support for both prototype and volume requirements. We offer rapid turnaround and competitive pricing while maintaining strict process control.

For inquiries about custom stack-ups, panel sizes, alternative Dk values within the TF series (3.0 to 16), single- or double-sided copper cladding, or other configurations, please contact our sales engineering team—we are ready to support your high-frequency circuit board requirements.