F4BTMS294 Double-sided copper clad laminate material substrate PCB built on 0.254mm, 0.508mm, 1.016mm

F4BTMS294 High-Reliability Copper Clad Laminate Description

The F4BTMS294 is an ultra-stable, ceramic-reinforced PTFE (Polytetrafluoroethylene) laminate engineered for the most demanding high-frequency and aerospace applications. As part of the advanced F4BTMS series from Taizhou Wangling Insulation Material Factory, it incorporates a high density of ceramic filler within a PTFE matrix and utilizes ultra-fine glass fabric to deliver exceptional electrical stability, low thermal expansion, and outstanding reliability. This material is designed as a direct, high-performance replacement for imported aerospace-grade substrates.

Core Technology and Composition
This material is formulated by blending PTFE resin with a significant load of specialized ceramic particles and minimal ultra-thin glass fabric. This composition drastically reduces the fiber-weave effect, minimizes anisotropy, and yields extremely low dielectric loss. A key feature of the F4BTMS294 is its capability to be supplied with 50Ω buried resistor foil, allowing the integration of thin-film resistor layers directly into the substrate for compact circuit designs. It is standardly clad with 1 oz (0.035mm) RTF (Reverse Treated Foil) low-profile copper to ensure superior high-frequency performance, excellent etchability for fine-line circuits, and robust peel strength.

F4BTMS294 Data Sheet

Key Electrical Specifications
The F4BTMS294 is characterized by its exceptionally stable and predictable electrical behavior:

Dielectric Constant (Dk): A nominal value of 2.94 at 10 GHz, with a controlled tolerance of ±0.04.

Dissipation Factor (Df): Maintains very low loss across a broad frequency range: 0.0012 at 10 GHz, 0.0014 at 20 GHz, and 0.0018 at 40 GHz.

Dielectric Constant Temperature Coefficient (TcDk): An outstandingly low -20 ppm/°C over -55°C to +150°C, indicating near-perfect electrical stability across extreme temperature variations, which is critical for phase-sensitive applications.

Standard Product Specifications

Copper Foil: Standard offering uses 1 oz RTF copper foil.

Special Option: Can be supplied with 50Ω buried resistor foil (Nickel-Phosphorus alloy, 50±5 Ω/sq).

Standard Thickness: Available in dielectric thicknesses based on 0.127mm (5 mil) multiples, with a minimum achievable thickness of 0.127mm. Common thicknesses include 0.254mm, 0.508mm, 1.016mm, etc., with precise tolerances (e.g., 1.524mm ±0.06mm).

Standard Panel Sizes: Standard sizes include 460mm x 610mm (18"x24") and 610mm x 920mm (24"x36").

Mechanical & Thermal Performance:

Peel Strength: >1.2 N/mm (with 1 oz RTF copper).

Coefficient of Thermal Expansion (CTE): Features an extremely low and matched CTE: XY-direction: 10-12 ppm/°C; Z-direction: 22 ppm/°C (-55°C to +288°C). This ensures unparalleled dimensional stability and plated-through-hole reliability under thermal cycling.

Thermal Conductivity (Z-direction): 0.58 W/(m·K), offering superior heat dissipation compared to standard PTFE laminates.

Max Operating Temperature: -55°C to +260°C.

Flammability Rating: UL 94 V-0.

Other Critical Properties:

Volume & Surface Resistivity: ≥1x10⁸ MΩ·cm and ≥1x10⁸ MΩ, respectively.

Moisture Absorption: Only 0.02%, ensuring performance stability in humid or vacuum environments (low outgassing).

Thermal Stress Reliability: Passes 3 cycles of 10 seconds at 260°C solder dip without delamination.

Electrical Strength (Z-direction): >40 kV/mm.

Breakdown Voltage (XY-direction): >48 kV.

Density: 2.25 g/cm³.

Typical Applications

Phased Array Antennas and Phase-Sensitive Components

Aerospace, Satellite, and Spacecraft Communication Systems

High-Frequency Radar and Military Electronics

Complex Multilayer and Backplane Structures

Circuits requiring integrated thin-film resistors

In summary, the F4BTMS294 is a premium aerospace-grade laminate that delivers a stable Dk of 2.94, ultra-low loss up to 40 GHz, and industry-leading thermal and dimensional stability. Its excellent thermal conductivity, extremely low moisture absorption, and optional buried resistor capability make it an indispensable, high-reliability solution for next-generation RF, microwave, and space electronics.