F4BME275 High-Frequency double sided Copper Clad Laminate | raw material | Substarte using for RF microwave PCB

F4BME275 High-Frequency Copper Clad Laminate Description

The F4BME275 is a high-performance, glass fiber-reinforced PTFE (Polytetrafluoroethylene) copper clad laminate designed for advanced microwave and RF applications where a moderately higher dielectric constant is required for circuit miniaturization, alongside excellent signal integrity and reliability. As part of the enhanced "E" series from Taizhou Wangling Insulation Material Factory, this material is specifically engineered with low-profile copper foil to meet critical Passive Intermodulation (PIM) performance standards.

Core Technology and Composition
The substrate is manufactured using a controlled formulation of woven glass fiber cloth and PTFE resin. The elevated glass fiber content, relative to lower-Dk variants in the series, provides improved dimensional stability and a higher dielectric constant. The defining feature of the F4BME series is the lamination with reverse-treated foil (RTF) copper, which is essential for achieving superior PIM characteristics (≤-159 dBc), enabling the fabrication of precise, high-density circuits, and minimizing signal loss at high frequencies.

F4BME275 Data Sheet

Key Electrical Specifications

Dielectric Constant (Dk): A nominal value of 2.75 at 10 GHz, with a controlled tolerance of ±0.05. This value facilitates significant circuit size reduction compared to lower-Dk materials.

Dissipation Factor (Df): Maintains a low loss tangent of 0.0015 at 10 GHz and 0.0021 at 20 GHz, ensuring good signal efficiency despite the higher Dk.

Dielectric Constant Temperature Coefficient (TcDk): -92 ppm/°C over a range of -55°C to +150°C, indicating stable electrical performance over temperature, with reduced temperature sensitivity compared to lower-Dk versions.

Standard Product Specifications

Copper Foil: Standard offering is with 1 oz (0.035mm) Reverse Treated Foil (RTF). A 0.5 oz (0.018mm) RTF option is also available.

Standard Thickness: Available in various total (copper+dielectric) or dielectric-only thicknesses. For the F4BME275 (Dk 2.7-3.0 range), the minimum achievable dielectric core thickness is 0.2mm. Common thicknesses include 0.508mm, 0.762mm, 1.524mm, etc., with corresponding tolerances (e.g., 1.524mm ±0.06mm).

Standard Panel Sizes: Includes efficient standard sizes such as 460mm x 610mm, 500mm x 600mm, and 914mm x 1220mm. Custom sizes are available upon request.

Mechanical & Thermal Performance:

Peel Strength: >1.6 N/mm (with 1 oz RTF copper).

Coefficient of Thermal Expansion (CTE): XY-direction: 14-16 ppm/°C; Z-direction: 112 ppm/°C (-55°C to 288°C). The increased glass content results in notably better dimensional stability (lower CTE).

Thermal Conductivity (Z-direction): 0.38 W/(m·K), offering slightly improved heat dissipation.

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

Flammability Rating: UL 94 V-0.

Other Critical Properties:

Volume & Surface Resistivity: ≥6x10⁶ MΩ.cm and ≥1x10⁶ MΩ, respectively.

Moisture Absorption: ≤0.08%.

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

Electrical Strength (Z-direction): >28 kV/mm.

Breakdown Voltage (XY-direction): >35 kV.

Typical Applications

Compact Power Dividers, Couplers, and Hybrids

Miniaturized Filters and Multiplexers

High-Density Interconnect (HDI) for RF Modules

Phased Array Antenna Elements requiring smaller footprints

Components for Satellite and Terrestrial Communication Systems

In summary, the F4BME275 is a high-reliability laminate that provides a stable dielectric constant of 2.75, low loss, and guaranteed low PIM performance. Its enhanced dimensional stability and thermal properties, resulting from a higher glass content, make it a robust and commercially viable choice for designers of compact, high-frequency electronic systems.