RO4003C Material Properties
| Property | Value | Test Condition |
|---|
| Dielectric constant (εᵣ) | 3.55 ± 0.05 | 10 GHz, 23°C |
| Loss tangent (tan δ) | 0.0027 | 10 GHz, 23°C |
| Thermal coefficient of εᵣ | +40 ppm/°C | — |
| CTE (x, y) | 11 ppm/°C | — |
| CTE (z) | 46 ppm/°C | — |
| Thermal conductivity | 0.64 W/m·K | — |
| Tg | >280°C | — |
| Available thickness | 0.203, 0.305, 0.508, 0.813 mm | — |
Why Choose RO4003C?
RO4003C is one of the most popular RF substrates because it combines:
- Low, stable dielectric constant (vs. FR4 at 4.2–4.8, drifts with frequency)
- Very low loss tangent (FR4: 0.02 at 1 GHz — 7× worse)
- Standard FR4-compatible processing (no special handling like PTFE)
- Good dimensional stability for etching precision
50 Ω Microstrip Line Widths on RO4003C
| Substrate Thickness (mm) | 50 Ω Line Width (mm) | Effective εᵣ |
|---|
| 0.203 | 0.450 | 2.98 |
| 0.305 | 0.678 | 2.99 |
| 0.508 | 1.130 | 3.01 |
| 0.813 | 1.808 | 3.02 |
Values calculated for 35 μm (1 oz) copper. Use RF View's microstrip calculator or a tool like Qucs/AppCAD to verify for your exact copper thickness.
Typical Applications
- Microstrip bandpass/bandstop filters at 1–40 GHz
- Power amplifier boards (5–30 GHz)
- LNA modules
- Phased array antenna elements
- Radar front-end modules
Comparing RO4003C to Other RF Substrates
| Substrate | εᵣ | tan δ (10 GHz) | Cost | Best For |
|---|
| FR4 | 4.2–4.8 | 0.015–0.025 | Low | <1 GHz, digital |
| RO4003C | 3.55 | 0.0027 | Medium | 1–30 GHz general RF |
| RO4350B | 3.66 | 0.0037 | Medium | Similar to RO4003C |
| RT/Duroid 5880 | 2.20 | 0.0009 | High | >30 GHz, mmWave |
| RO3010 | 10.2 | 0.0022 | High | Compact, high-εᵣ designs |
Related Topics
← Back to Component Guide
·
RF View Home