What material is Rogers RO4003C?

Introduction to Rogers RO4003C Dielectric Material

Rogers RO4003C is a high-performance dielectric material widely used in the electronics industry for printed circuit boards (PCBs) and high-frequency applications. This advanced material is engineered to provide excellent electrical properties, dimensional stability, and reliability in demanding environments.

Key Properties of Rogers RO4003C

Rogers RO4003C exhibits several key properties that make it an ideal choice for many applications:

1. Low dielectric constant (Dk) of 3.38 at 10 GHz
2. Low dissipation factor (Df) of 0.0027 at 10 GHz
3. Excellent thermal stability
4. Low moisture absorption
5. High tensile modulus and strength

These properties enable Rogers RO4003C to deliver consistent performance across a wide range of frequencies and temperatures.

Composition and Structure of Rogers RO4003C

Polymer Matrix

The base material of Rogers RO4003C is a reinforced hydrocarbon and ceramics thermoset polymer matrix. This matrix provides the foundation for the material’s mechanical and thermal properties, ensuring a stable platform for the embedded glass and ceramic fillers.

Glass and Ceramic Fillers

Rogers RO4003C incorporates a carefully selected combination of glass and ceramic fillers within the polymer matrix. These fillers are chosen for their ability to enhance the material’s electrical properties, particularly its dielectric constant and dissipation factor.

The specific types and proportions of glass and ceramic fillers used in Rogers RO4003C are proprietary information. However, it is known that the fillers are uniformly distributed throughout the matrix to ensure consistent performance across the entire material.

Electrical Properties of Rogers RO4003C

Dielectric Constant (Dk)

The dielectric constant, also known as the relative permittivity, is a measure of a material’s ability to store electrical energy in an electric field. A lower dielectric constant is generally preferred for high-frequency applications, as it minimizes signal propagation delay and reduces the risk of signal integrity issues.

Rogers RO4003C has a dielectric constant of 3.38 at 10 GHz, which is considered a low value for a PCB substrate material. This low Dk helps to minimize signal distortion and attenuation, making RO4003C suitable for high-speed digital and RF applications.

Dissipation Factor (Df)

The dissipation factor, also known as the loss tangent, is a measure of a material’s ability to dissipate electrical energy as heat. A lower dissipation factor is desirable, as it minimizes signal loss and improves the overall efficiency of the electronic system.

Rogers RO4003C has a dissipation factor of 0.0027 at 10 GHz, which is considered an extremely low value. This low Df ensures minimal signal loss, even at high frequencies, making RO4003C an excellent choice for applications requiring high signal integrity and low power consumption.

Frequency Dependence

The electrical properties of dielectric materials can vary with frequency. In the case of Rogers RO4003C, both the dielectric constant and dissipation factor remain relatively stable across a wide frequency range.

Frequency (GHz)	Dielectric Constant (Dk)	Dissipation Factor (Df)
1	3.38	0.0027
5	3.38	0.0027
10	3.38	0.0027
20	3.39	0.0028
30	3.40	0.0029

This stability in electrical properties makes Rogers RO4003C suitable for broadband applications, where consistent performance is required across multiple frequency bands.

Mechanical Properties of Rogers RO4003C

Tensile Strength and Modulus

Rogers RO4003C exhibits excellent mechanical strength and rigidity, thanks to its reinforced polymer matrix and carefully selected filler materials. The material has a tensile strength of 139 MPa (20,200 psi) and a tensile modulus of 12.4 GPa (1,800 kpsi).

These high values ensure that RO4003C can withstand the stresses and strains encountered during PCB manufacturing and assembly processes, as well as in the final application environment.

Dimensional Stability

Dimensional stability is a critical factor in PCB design, as changes in the substrate dimensions can lead to misalignment of traces and components, resulting in performance degradation or even failure.

Rogers RO4003C exhibits excellent dimensional stability, with a low coefficient of thermal expansion (CTE) of 11 ppm/°C in the X-Y plane and 46 ppm/°C in the Z-axis. This low CTE helps to minimize warping and twisting of the PCB substrate, ensuring reliable performance over a wide temperature range.

Thermal Properties of Rogers RO4003C

Thermal Conductivity

Thermal conductivity is a measure of a material’s ability to conduct heat. A higher thermal conductivity is desirable for PCB substrates, as it helps to dissipate heat generated by electronic components, preventing hotspots and improving overall system reliability.

Rogers RO4003C has a thermal conductivity of 0.71 W/m·K, which is considered a moderate value for a PCB substrate material. While not as high as some ceramic-based substrates, this thermal conductivity is sufficient for many applications, particularly when combined with appropriate thermal management techniques.

Glass Transition Temperature (Tg)

The glass transition temperature (Tg) is the temperature at which a polymer material transitions from a rigid, glassy state to a softer, rubbery state. It is important for PCB substrates to have a high Tg to ensure mechanical stability and prevent deformation at elevated temperatures.

Rogers RO4003C has a glass transition temperature of 280°C (536°F), which is considered a high value for a polymer-based substrate. This high Tg ensures that RO4003C maintains its mechanical properties and dimensional stability even at high operating temperatures.

Applications of Rogers RO4003C

High-Frequency PCBs

Rogers RO4003C is primarily used in the design and fabrication of high-frequency printed circuit boards. Its low dielectric constant and dissipation factor make it an ideal choice for applications such as:

1. Wireless communication systems (e.g., 5G, Wi-Fi, Bluetooth)
2. Radar and satellite communication equipment
3. High-speed digital circuits
4. Microwave and millimeter-wave devices

In these applications, RO4003C helps to minimize signal loss, distortion, and crosstalk, ensuring reliable performance and data integrity.

Multilayer PCBs

Rogers RO4003C is also well-suited for use in multilayer PCBs, thanks to its excellent dimensional stability and thermal properties. The material’s low CTE helps to minimize stress and deformation in complex multilayer structures, while its moderate thermal conductivity aids in heat dissipation.

In multilayer PCBs, RO4003C is often combined with other materials, such as FR-4 or other Rogers laminates, to create hybrid structures that balance cost, performance, and manufacturability.

Processing and Fabrication of Rogers RO4003C

PCB Manufacturing Processes

Rogers RO4003C is compatible with standard PCB manufacturing processes, including:

1. Drilling and routing
2. Copper plating and etching
3. Solder mask application
4. Silk screen printing

However, due to its unique properties, some adjustments to the processing parameters may be necessary to achieve optimal results. For example, the drilling and routing speeds may need to be reduced compared to FR-4 to minimize burring and ensure clean, accurate holes and edges.

Bonding and Lamination

Rogers RO4003C can be bonded to other PCB materials, such as FR-4 or additional RO4003C layers, using standard lamination processes. The recommended bonding temperature for RO4003C is 188-200°C (370-392°F), with a bonding pressure of 200-400 psi and a dwell time of 60-90 minutes.

Proper control of the bonding process parameters is essential to ensure good adhesion between layers and to minimize the risk of delamination or other defects.

Comparison with Other PCB Substrate Materials

Rogers RO4003C vs. FR-4

FR-4 is the most widely used PCB substrate material, known for its low cost and good mechanical properties. However, FR-4 has several limitations compared to Rogers RO4003C:

1. Higher dielectric constant (Dk) of 4.3-4.7
2. Higher dissipation factor (Df) of 0.02-0.03
3. Lower glass transition temperature (Tg) of 130-140°C
4. Higher moisture absorption

These properties make FR-4 less suitable for high-frequency applications, where signal integrity and low loss are critical. Rogers RO4003C, with its superior electrical and thermal properties, is a better choice for demanding RF and microwave circuits.

Rogers RO4003C vs. Other High-Frequency Substrates

Rogers RO4003C competes with several other high-frequency substrate materials, such as:

1. Rogers RO4350B
2. Isola I-Tera MT40
3. Taconic RF-35

These materials offer similar electrical properties, with dielectric constants ranging from 3.3 to 3.5 and dissipation factors in the range of 0.0025 to 0.0035. The choice between these materials often depends on specific application requirements, cost considerations, and designer preference.

Frequently Asked Questions (FAQ)

1. What is the main difference between Rogers RO4003C and FR-4?

Rogers RO4003C has a lower dielectric constant and dissipation factor compared to FR-4, making it more suitable for high-frequency applications. RO4003C also has a higher glass transition temperature and better dimensional stability.

2. Can Rogers RO4003C be used for low-frequency applications?

While Rogers RO4003C is primarily designed for high-frequency applications, it can also be used for low-frequency circuits. However, its higher cost compared to FR-4 may not be justified for simple, low-frequency designs.

3. How does the cost of Rogers RO4003C compare to other PCB substrate materials?

Rogers RO4003C is generally more expensive than FR-4 due to its advanced properties and specialized manufacturing processes. However, it is competitively priced compared to other high-frequency substrate materials, such as Rogers RO4350B and Isola I-Tera MT40.

4. What are the challenges in processing Rogers RO4003C?

Processing Rogers RO4003C may require some adjustments to standard PCB manufacturing processes, such as reduced drilling and routing speeds to minimize burring and ensure clean, accurate holes and edges. Proper control of bonding and lamination parameters is also essential to ensure good adhesion between layers and minimize the risk of defects.

5. Is Rogers RO4003C suitable for multilayer PCBs?

Yes, Rogers RO4003C is well-suited for use in multilayer PCBs, thanks to its excellent dimensional stability and thermal properties. Its low CTE helps to minimize stress and deformation in complex multilayer structures, while its moderate thermal conductivity aids in heat dissipation.

Conclusion

Rogers RO4003C is an advanced dielectric material that offers excellent electrical, mechanical, and thermal properties for high-frequency PCB applications. Its low dielectric constant and dissipation factor, combined with its dimensional stability and high glass transition temperature, make it an ideal choice for demanding RF, microwave, and high-speed digital circuits.

While more expensive than traditional FR-4, Rogers RO4003C is competitively priced compared to other high-performance substrate materials. Its compatibility with standard PCB manufacturing processes, albeit with some adjustments, makes it a practical choice for a wide range of applications.

As the demand for high-speed, high-frequency electronics continues to grow, materials like Rogers RO4003C will play an increasingly important role in enabling the next generation of wireless communications, radar systems, and advanced digital devices.