Rogers High-Frequency Laminate Selection Notes: RO4003C, RO4350B, and RT5880 Parameters and Engineering Trade-offs

In 5G communications, millimeter-wave radar, satellite links, and similar designs, high-frequency laminate properties such as Dk and Df directly affect link loss, impedance consistency, and mass-production behavior. Rogers offers many material grades, but RO4003C, RO4350B, and RT5880 are frequently placed side by side in the same comparison. These three materials are not simply low-end, mid-range, and high-end replacements for one another. Selection must consider frequency, flame rating, CTE, process route, and cost at the same time.

The following notes are organized from Rogers official datasheets and PCB fabrication experience, covering parameters, processes, and application scenarios to help hardware and RF PCB engineers make faster judgments.

1. Understand the Material Families First

RO4000 Series

Representative grades: RO4003C, RO4350B.
System: hydrocarbon + ceramic filler.

Positioning: a balance between RF performance and FR-4 manufacturability, suitable for a large number of mid-to-high-frequency projects.

RO3000 Series
Representative grade: RO3003.
System: PTFE + ceramic filler.

Positioning: a common baseline material for millimeter-wave bands, frequently seen in 77 GHz radar.

RT/duroid Series
Representative grade: RT5880.
System: PTFE + glass microfiber reinforcement.

Positioning: an ultra-low-loss, high-end material for higher frequencies or designs that are extremely sensitive to attenuation.

2. Key Parameter Comparison

RO4003C

Material system: hydrocarbon + ceramic
Dielectric constant Dk (@10 GHz): 3.38 ± 0.05
Loss tangent Df (@10 GHz): 0.0027
Flame rating: UL94 non-FR (NON FR; not UL94 V-0)
Z-axis CTE: 46 ppm/°C
Upper frequency limit: 40 GHz
Process: FR-4 compatible
Cost level: medium, about 3–4x FR-4

RO4350B

Material system: hydrocarbon + ceramic
Dielectric constant Dk (@10 GHz): 3.48 ± 0.05
Loss tangent Df (@10 GHz): 0.0037
Flame rating: UL94 V-0
Z-axis CTE: 32 ppm/°C
Upper frequency limit: 35 GHz
Process: FR-4 compatible
Cost level: medium, about 3–4x FR-4

RT/duroid 5880

Material system: PTFE + glass microfiber
Dielectric constant Dk (@10 GHz): 2.20 ± 0.02
Loss tangent Df (@10 GHz): 0.0009
Flame rating: UL94 non-FR
Z-axis CTE: 130–237 ppm/°C
Upper frequency limit: 110 GHz+
Process: requires PTFE-specific processes, such as plasma activation
Cost level: high, about 8–10x FR-4

Data source: Rogers official datasheets.

3. How to Position the Three Materials

The Dk, Df, CTE, and upper frequency values below are based on Rogers official datasheets.

RO4350B: The Balanced Workhorse

RO4350B has a Dk of 3.48 ± 0.05 and a Df of 0.0037 @10 GHz. Its strength is overall balance: it can run on standard FR-4 flows without requiring a dedicated PTFE production line; it passes UL94 V-0; its Z-axis CTE is 32 ppm/°C, which gives relatively good thermal expansion matching with copper at about 17 ppm/°C; and its stable operating frequency can reach 35 GHz.

Suitable scenarios:
5G Sub-6 GHz base station power amplifiers and antennas
24 GHz automotive radar
GPS antennas and RFID readers
Cost-sensitive mid-to-high-frequency RF projects
RO4003C: The Low-Loss Cost-Performance Route

RO4003C also belongs to the RO4000 series, but it offers lower Df at 0.0027 @10 GHz, with a Dk of 3.38 ± 0.05. Within the RO4000 family, its loss performance is more outstanding. Its upper frequency limit can reach 40 GHz, it is also FR-4 compatible, and its cost level is close to that of RO4350B, at about 3–4x FR-4.

Points to note:
Its Z-axis CTE is 46 ppm/°C, higher than the 32 ppm/°C of RO4350B.
RO4003C does not carry a UL94 V-0 rating. If a project mandates UL94 V-0, use a material such as RO4350B instead.
Suitable scenarios:
Low-noise amplifiers (LNAs)
High-frequency filters and couplers
RF front ends with tighter insertion-loss requirements
RT/duroid 5880: Millimeter-Wave and Ultra-Low-Loss Performance

RT5880 has a Dk of only 2.20 ± 0.02 and a Df as low as 0.0009 @10 GHz, roughly one-third that of RO4003C. Its upper frequency limit can reach 110 GHz+, making it suitable for millimeter-wave, satellite communications, aerospace, phased-array radar, E-band backhaul, and similar applications. In 77 GHz automotive radar, RT5880 is a common choice, and RO3003 is also often used in that band.

Processing and cost require careful evaluation:
The PTFE-based material is relatively soft, and via-wall adhesion needs to be ensured by pre-treatment such as plasma activation.
Drilling parameters cannot simply copy those used for standard FR-4, and standard HDI laser drilling is not directly suitable.
Cost is about 8–10x FR-4, and lead times are usually longer.
It does not carry a UL94 flame rating.
4. Three-Step Selection Method

Step 1: Define the Operating Frequency
Below 6 GHz: prioritize RO4350B for a balance of performance and cost.
6–30 GHz: both RO4350B and RO4003C can be evaluated; when loss requirements are tighter, RO4003C is more suitable.
30–77 GHz: this enters the millimeter-wave region. Evaluate RO3003 or RT5880; for extreme low loss, choose RT5880.
Above 77 GHz: the Df = 0.0009 advantage of RT5880 becomes clear, making it the more common choice.
Step 2: Check Flame Rating and Certification

Need UL94 V-0: choose RO4350B.
No flame-retardant requirement, with performance as the priority: consider RT5880.
Because RO4003C does not carry UL94 V-0, it is not listed as a flame-compliance recommendation.
Step 3: Evaluate Process Cost and Lead Time
RO4000 series: FR-4 compatible, relatively low processing difficulty, cost about 3–4x FR-4, usually faster lead times.
RT5880: requires PTFE-specific processes, higher processing difficulty, cost about 8–10x FR-4, usually longer lead times.
5. Common Selection Pitfalls

Pitfall 1: RO4350B is always better than RO4003C.
The two have different strengths. RO4003C has lower Df at 0.0027; RO4350B has better Z-axis CTE at 32 ppm/°C and carries a UL94 V-0 rating, while RO4003C is non-FR.

Pitfall 2: Just use RT5880 for any high-frequency project.
RT5880 does deliver top performance, but its processing difficulty and cost are also much higher. Below 30 GHz, the RO4000 series is often fully sufficient, and the overall cost can be significantly lower.

Pitfall 3: RO4000 series processes exactly like FR-4.
Although the RO4000 series is compatible with standard FR-4 processes, etch factor still needs to be controlled, CTE matching must be considered during mixed lamination, and impedance control must still follow high-frequency PCB standards.

Conclusion
RO4350B is suitable as a balanced workhorse material. RO4003C is better for loss-sensitive designs that also require cost efficiency. RT5880 targets millimeter-wave and ultra-low-loss scenarios. When selecting, follow the sequence of frequency → flame rating and certification → process cost and lead time. 30 GHz is an important dividing line. Above 77 GHz, the Df advantage of RT5880 becomes more critical. Finally, confirm whether the production line has the corresponding process capability, so that the right material does not fail at fabrication.