Advanced PCB-ROGERS 4350B

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ROGERS 4350B is an advanced printed circuit board (PCB) material made by Rogers Corporation. It offers excellent dielectric properties and is well-suited for use in high frequency and high speed digital circuits. Some key features of ROGERS 4350B include:

  • Low dielectric constant and loss tangent for high frequency performance
  • Good thermal conductivity for heat dissipation
  • Low Z-axis expansion for reliability
  • High Tg for excellent mechanical and electrical performance
  • Excellent dimensional stability
  • UL 94V-0 flame retardancy rating

In this comprehensive guide, we will cover the key properties, applications, designs considerations and benefits of using advanced ROGERS 4350B PCBs.


ROGERS 4350B has the following key properties that make it advantageous for high frequency and high speed digital circuits:

Low Dielectric Constant and Loss Tangent

  • Dielectric constant (Dk) of 3.48 at 10 GHz
  • Loss tangent (Df) of 0.0037 at 10 GHz

The low dielectric constant minimizes signal loss and allows higher frequency operation. The low loss tangent means less signal attenuation for optimal high frequency performance.

Thermal Conductivity

  • Thermal conductivity of 0.70 W/m/K

The thermal conductivity allows heat generated during circuit operation to dissipate quickly. This improves overall reliability and prevents hot spots.

Coefficient of Thermal Expansion (CTE)

  • X-Y axis CTE of 10 ppm/°C
  • Z axis CTE of 30 ppm/°C

The low CTE in the X-Y plane minimizes dimensional changes during thermal cycling. This improves reliability and tolerance to temperature changes.

Glass Transition Temperature

  • Tg of >280°C

The high glass transition temperature allows ROGERS 4350B to withstand high lead-free soldering temperatures during assembly.

Flame Retardancy

  • Rated UL 94V-0

The V-0 rating indicates ROGERS 4350B is self-extinguishing and does not promote flames. This makes it suitable for safety-critical applications.

Dielectric Strength

  • Dielectric strength of >1.5 kV/mil

High dielectric strength allows ROGERS 4350B to withstand high operating voltages without electrical breakdown.


The properties of ROGERS 4350B make it well-suited for the following types of high frequency and high speed applications:

5G Communications

The low loss and stable electrical performance of ROGERS 4350B allows it to support emerging 5G technology operating at mmWave frequencies up to 90 GHz. It can be used for 5G antennas, base stations, and infrastructure.

Aerospace and Defense

ROGERS 4350B meets stringent aerospace and defense requirements for high frequency radar, communications, guidance, and avionics systems. It offers consistent performance under extreme conditions.

Automotive RADAR

Radar systems for collision avoidance, adaptive cruise control, and other automotive applications rely on stable electrical properties. ROGERS 4350B enables these systems to operate reliably.

High Speed Digital Circuits

With rising edge rates and data rates, ROGERS 4350B provides the low loss needed for error-free transmission in high speed PCBs. This includes servers, routers, and computing applications.

Microwave and mmWave Electronics

The stable electrical properties of ROGERS 4350B over wide frequency ranges make it suitable for microwave PCBs operating well into the millimeter wave region.

Design Considerations

Here are some key considerations when designing PCBs using ROGERS 4350B:

Signal Integrity

The consistent Dk and Df values of ROGERS 4350B across frequency ranges allows more accurate modeling and optimization of signal traces for high frequency performance. Controlled impedance interfaces can be maintained.

Stack-up Configuration

ROGERS 4350B is often used in multi-layer PCBs with complex layer stack-ups. Layer sequencing and orientations must be modeled properly to ensure correct functionality. Differential pairs and stripline configurations are common.

Thermal Management

The thermal conductivity of ROGERS 4350B allows heat to be conducted across the PCB. This must be accounted for in thermal modeling to ensure components do not exceed temperature limits. Thermal vias help.

Material Thickness

ROGERS 4350B is available in different thicknesses. Thicker material can allow higher voltage operation. Thinner material provides flexibility and reduces weight. Models must account for thickness effects.

Copper Weight

The trend is towards thinner copper to allow fine lines and spaces. However, higher copper weights improve thermal conductivity. Models help optimize copper weight for electrical and thermal performance.

Via Structures

Vias connect traces between layers in multilayer PCBs. Their size, spacing, and anti-pad diameters require careful tuning to avoid interfering with impedance control and generating reflections.

Lamination Cycles

The lamination cycle parameters for ROGERS 4350B, including pressure, temperature, and time, must align with manufacturer guidelines to achieve proper material properties and mitigate reliability risks.

Fabrication Process

ROGERS 4350B requires specialized fabrication processes that account for material properties. Steps like drilling, routing, plating, and etching must be done properly to prevent damage.


Here are some of the key benefits provided by advanced ROGERS 4350B PCB material:

High Frequency Performance

The stable low dielectric constant and loss tangent of ROGERS 4350B are engineered specifically to enable high frequency operation beyond 10 GHz without excessive signal loss.


The low Dk allows closer component spacing and routing, supporting higher densities and smaller overall circuit sizes. This enables miniaturization.

Noise Isolation

ROGERS 4350B provides high isolation between closely spaced circuits. This reduces electromagnetic interference and crosstalk for better signal integrity.

Improved Impedance Control

Consistent Dk and Df values allow better impedance matching of traces and interfaces. This minimizes signal reflections and maximizes power transfer.


The properties of ROGERS 4350B remain stable over time and operating conditions. This improves long term reliability under thermal cycling and use.

High Speed Signals

The low loss tangent of ROGERS 4350B allows high speed digital signals with fast edge rates to propagate without attenuation and dispersion.

Thermal Dissipation

The thermal conductivity efficiently dissipates heat from components mounted on the PCB. This prevents localized hot spots.

Design Flexibility

ROGERS 4350B is available in different thicknesses and can be combined in multilayer stacks. This allows flexibility in designing layer configurations.


The UL 94V-0 rating assures ROGERS 4350B will not spread flames. This makes it suitable for mission-critical safety equipment.


ROGERS 4350B provides an optimal set of electrical, thermal, and mechanical properties tailored specifically for high frequency and high speed PCB applications. The low and stable dielectric constant and loss tangent enable miniaturized circuits with excellent signal integrity at microwave and mmWave frequencies for emerging 5G, RADAR, aerospace, defense and computing applications.

Careful modeling and design is required to leverage the benefits of ROGERS 4350B correctly based on parameters like stack-up, trace geometries, and fabrication details. When designed properly, ROGERS 4350B allows advanced PCBs to achieve superior high frequency performance and reliability under demanding operating conditions.

Frequently Asked Questions

What is the dielectric constant and loss tangent of ROGERS 4350B?

ROGERS 4350B has a dielectric constant of 3.48 and loss tangent of 0.0037 measured at 10 GHz. These low values allow high frequency operation with minimal signal loss.

What thickness variations is ROGERS 4350B available in?

Standard thicknesses range from 0.002″ (0.05 mm) to 0.062″ (1.57 mm). Non-standard thicknesses up to 0.125″ (3.18 mm) can be sourced. Thinner material provides flexibility while thicker material allows higher voltage isolation.

Can ROGERS 4350B be used for multilayer PCBs?

Yes, ROGERS 4350B is well-suited for complex multilayer PCBs thanks to excellent dimensional stability for registration and via reliability. It allows intricate layer stack-ups with high layer counts.

Does ROGERS 4350B require special fabrication processes?

ROGERS 4350B requires precision drilling, routing, imaging, and lamination processes tailored for its material properties. Standard FR-4 processes may not provide acceptable results. Proper handling is also required.

What finish and plating is used with ROGERS 4350B PCBs?

A common finish is ENIG (Electroless Nickel Immersion Gold) which provides good solderability. Other finishes like immersion silver or OSP (Organic Solderability Preservative) can also be used. Plated through holes use copper plating.