RO3003 is a ceramic-filled PTFE laminate used where low dielectric loss and a relatively stable temperature response are useful in RF and millimeter-wave circuits. It has no woven-glass reinforcement. The two published Design Dk observations in this record deliberately retain their different frequency conditions instead of collapsing them into one number.
Material system
Ceramic-filled PTFE
Technical properties
| Property | Reported value | Conditions / source |
|---|---|---|
| Process dielectric constant | 3.00 ± 0.04 | Typical, 10 GHz, 23°C; IPC-TM-650 2.5.5.5 clamped stripline; thickness direction. Source |
| Design dielectric constant | 3 | Typical, 8–40 GHz; differential phase length method. Average across the common constructions in the cited datasheet. Source |
| Dissipation factor | 0.001 | Typical, 10 GHz, 23°C; IPC-TM-650 2.5.5.5; thickness direction. Source |
| Thermal conductivity | 0.5 W/(m·K) | Typical; ASTM D5470, 50°C, through-thickness direction. Source |
| Design dielectric constant | 3.16 | Typical; 77 GHz differential phase length method, selector guide footnote 29. Distinct frequency from the 8–40 GHz datasheet Design Dk observation. Source |
| CTE, X axis | 17 ppm/°C | Typical; -55°C to 288°C, IPC-TM-650 2.4.41; average expansion over the interval, not necessarily linear. Source |
| CTE, Y axis | 16 ppm/°C | Typical; -55°C to 288°C, IPC-TM-650 2.4.41; average expansion over the interval, not necessarily linear. Source |
| CTE, Z axis | 25 ppm/°C | Typical; -55°C to 288°C, IPC-TM-650 2.4.41; average expansion over the interval, not necessarily linear. Source |
| Thermal coefficient of dielectric constant | -3 ppm/°C | Typical; -50°C to 150°C, IPC-TM-650 2.5.5.5 (modified temperature measurement); 10 GHz. Source |
| Water absorption | 0.04 % | Typical; D48/50, IPC-TM-650 2.6.2.1. Source |
| Density | 2.1 g/cm³ | Typical; 23°C, ASTM D792. 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
- Use it for low-loss feeds, resonators or antenna layers when the fabricator has a qualified PTFE process. Evaluate whether its mechanical handling and bonding route fit the proposed board architecture.
- For a 77 GHz design, examine the selector's 3.16 differential-phase observation; the laminate datasheet lists 3.00 over 8–40 GHz. Select and validate the relevant model rather than averaging the numbers.
Thickness and copper options
The selected core thickness and tolerance must match the datasheet offering. The selector's 60 mil process-Dk footnote is relevant to thick samples.
ED and rolled foil availability depends on construction. Foil roughness must remain an independent transmission-line input.
Fabrication considerations
- Discuss drilling, hole-wall preparation and the bonding system before releasing a multilayer stackup. PTFE surface activation for plated holes and preparation for high-temperature fusion bonding are different process questions; instructions for one operation must not be applied blindly to another.
Application fit
- Low-loss RF feeds
- Millimeter-wave antennas
- Microwave resonators
Limits and substitution checks
- The selector notes a process-test thickness effect for 60 mil RO3003. A single Dk value is therefore insufficient for all thicknesses and frequencies. Automatic presets are disabled here until the designer chooses the relevant observation and construction.