| Term | Meaning in ceramic circuit engineering |
|---|---|
| Al₂O₃ / alumina | Aluminum oxide material family. |
| AlN | Aluminum nitride material family. |
| Si₃N₄ | Silicon nitride material family. |
| ZTA | Zirconia-toughened alumina, an alumina-based composite. |
| DBC / DCB | Direct bonded copper / direct copper bonding. |
| DPC | Direct plated copper circuit process. |
| AMB | Active metal brazing used to join metal and ceramic. |
| LTCC | Low-temperature co-fired ceramic system. |
| HTCC | High-temperature co-fired ceramic system. |
| CTE | Coefficient of thermal expansion, commonly expressed in ppm/K. |
| k | Thermal conductivity, in W/m·K. |
| Rθ | Thermal resistance of a defined path, in K/W. |
| Dk / εr | Relative dielectric constant under stated conditions. |
| Df / tan δ | Dielectric loss factor under stated conditions. |
| NRE | Non-recurring engineering, tooling or setup cost. |
| DFM | Design for manufacturability review. |
Name the level of the decision
A substrate material, metallization route, package format and finished assembly describe different levels of a design. An AlN substrate can be incorporated into several processes, and a co-fired package can include multiple materials and attachments.
Keep quantities and units separate
Thermal conductivity is a material property; thermal resistance depends on geometry and heat flow. CTE is an expansion coefficient; differential displacement also depends on length and temperature change. These quantities are not interchangeable even when discussed in the same comparison.
Use the drawing to resolve ambiguity
Terms such as double-sided, multilayer, gold finish and high temperature need a construction or numerical requirement. When a term can mean two things, attach a cross-section, material callout or test definition to the specification.
Engineering example
“Low thermal resistance” needs a defined structure and boundary conditions. “High thermal conductivity” describes a material value under stated conditions; it does not automatically describe the finished package.
Before you release the design
- Separate material names from process names.
- Include units and test conditions with values.
- Resolve ambiguous terms in the drawing.
Sources and further technical reading
Manufacturer references support the material and process context. Worked examples and checklists are engineering guidance; they are not test results or supplier guarantees.