RT/duroid 6202 is a woven-glass-reinforced, ceramic-filled PTFE laminate with a documented dependence of Dk on core thickness. Reinforcement and relatively low expansion make it a candidate for dimensionally controlled microwave structures. The product's headline Dk only describes part of the available construction range.
Material system
Filled PTFE with woven-glass reinforcement; construction-specific
Technical properties
| Property | Reported value | Conditions / source |
|---|---|---|
| Dissipation factor | 0.0015 | Typical, 10 GHz, 23°C; IPC-TM-650 2.5.5.5; direction is not separately recorded here. Source |
| Thermal conductivity | 0.68 W/(m·K) | Typical; ASTM C518, 80°C; through-thickness thermal conduction. Source |
| Process dielectric constant | 3.06 ± 0.04 at 5 mil; 3.02 ± 0.04 at 10/15 mil; 2.94 ± 0.04 at ≥20 mil | Typical; 10 GHz, 23°C, Z direction, IPC-TM-650 2.5.5.5; thickness-specific values, datasheet footnote 3. Source |
| Thermal coefficient of dielectric constant | 5 ppm/°C | Typical; -50°C to 150°C, IPC-TM-650 2.5.5.5 (modified temperature measurement); 10 GHz. Source |
Typical reported values are not a purchase specification. Process Dk, design Dk and values measured at different frequencies are not interchangeable.
Selection and design notes
- Choose the electrical spacing first, then select the corresponding Dk: the sheet distinguishes 5 mil, 10/15 mil and thicker cores. This is especially important when a stackup revision changes only the dielectric thickness on a drawing.
- For a phase-sensitive network, compare not only dielectric tolerance but also physical expansion and registration. Similar room-temperature impedance does not establish the same thermal phase behavior.
Thickness and copper options
The product sheet lists 5, 20 and 30 mil standard offerings and thickness-specific Dk notes covering 10 and 15 mil as well.
ED and rolled copper are listed; optional resistive or reverse-treated claddings must be specified explicitly.
Fabrication considerations
- Preserve thickness and reinforcement details through procurement and ask the fabricator to qualify PTFE drill preparation and plating. Confirm any proposed resistive or reverse-treated foil as a separate construction with its own process requirements.
Application fit
- Dimensionally stable RF boards
- Reinforced PTFE multilayers
- Precision microwave feeds
Limits and substitution checks
- No universal Dk preset is offered because choosing the thick-core number for a thin laminate would hide a known construction effect. RT/duroid 6202PR has distinct planar-resistor features and data; its name is not permission to replace standard 6202 without redesign and process review.