TMM 10 is a higher-permittivity ceramic-filled thermoset laminate for compact microwave circuitry. Its nominal process Dk is 9.20, not the number suggested by reading the product name literally. It is also different from TMM 10i, which has its own dielectric values and material response.
Material system
Ceramic-filled thermoset polymer
Technical properties
| Property | Reported value | Conditions / source |
|---|---|---|
| Process dielectric constant | 9.20 ± 0.230 | Typical; 10 GHz, Z direction; IPC-TM-650 2.5.5.5. Test temperature is not stated in this datasheet row. Source |
| Design dielectric constant | 9.8 | Typical, 8–40 GHz; differential phase length method. Average across the common constructions in the cited datasheet. Source |
| Dissipation factor | 0.0022 | Typical; 10 GHz, Z direction; IPC-TM-650 2.5.5.5. Test temperature is not stated in this datasheet row. Source |
| Thermal conductivity | 0.76 W/(m·K) | Typical; 80°C, Z direction, ASTM C518; product datasheet thermal table. Source |
| CTE, X axis | 21 ppm/°C | Typical; 0°C to 140°C; ASTM E831 and IPC-TM-650 2.4.41, product datasheet. Source |
| CTE, Y axis | 21 ppm/°C | Typical; 0°C to 140°C; ASTM E831 and IPC-TM-650 2.4.41, product datasheet. Source |
| CTE, Z axis | 20 ppm/°C | Typical; 0°C to 140°C; ASTM E831 and IPC-TM-650 2.4.41, product datasheet. Source |
| Thermal coefficient of dielectric constant | -38 ppm/°C | Typical; -55°C to 125°C, IPC-TM-650 2.5.5.5 (modified temperature measurement); frequency not separately stated in this datasheet row. Source |
| Water absorption | 0.09 % | Typical; D24/23, 0.050 inch (1.27 mm) specimen, ASTM D570; product datasheet, not the selector's different moisture conditions. 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 when the footprint benefit of a high-Dk resonator or matching network is important. Verify the smallest etched gaps and trace widths against the fabricator's capability before committing to a compact topology.
- Compare TMM 10 and TMM 10i with the same electrical requirements, then evaluate the differences in Design Dk, loss and anisotropy relevant to the field orientation. Do not exchange names on an existing drawing.
Thickness and copper options
Select the product-specific thickness from the TMM table; confirm any thick or mechanically machined configuration separately.
ED copper options must be included in the RF and fabrication specification; final plating adds another geometric variable.
Fabrication considerations
- Plan machining, drilling and copper adhesion checks for the ceramic-filled thermoset. A compact component with narrow lands may place different demands on handling and edge quality than a large continuous RF plane.
Application fit
- Miniaturized microwave filters
- High-Dk matching circuits
- Compact resonators
Limits and substitution checks
- The stated Dk is not a guarantee of resonator Q or component bandwidth. Higher permittivity can make a circuit more sensitive to dimensional and coupling errors. Temperature dependence is also material-specific, so an apparently equivalent high-Dk replacement requires electrical retuning and environmental verification.