Factors affecting the bending strength of aluminum nitride substrates

The influencing factors of the flexural strength of aluminum nitride substrates mainly include the following aspects:

Parameters and conditions during the preparation process: The flexural strength of aluminum nitride depends largely on the parameters and conditions during its preparation, such as temperature, pressure and time. For example, the new high-performance aluminum nitride substrate Alunit® AlN HP launched by CeramTec has a flexural strength that is 40% higher than that of traditional substrates, which is closely related to the optimization of the preparation process.

Microstructure: The microstructure of aluminum nitride has a significant impact on its flexural strength. The thermal conduction mechanism of single crystal AlN is phonon heat transfer, so the thermal conductivity and flexural strength of aluminum nitride may be controlled by grain boundaries, interfaces, second phases, defects, electrons and the scattering of phonons themselves in the crystal. Influence. The fewer defects and impurities, the higher the flexural strength of aluminum nitride is likely to be.

Temperature: Although the strength of aluminum nitride is not greatly affected by temperature, its flexural strength may still change at extreme temperatures. For example, when the temperature is 1300°C, the high-temperature strength of aluminum nitride is approximately 20% lower than that at room temperature. However, aluminum nitride's strength decreases less at high temperatures than aluminum oxide and silicon nitride.

Chemical properties: The temperature at which aluminum nitride begins to oxidize is about 700°C ~ 800°C. When aluminum nitride materials are used at room temperature, their flexural strength is not easily affected by oxidation. However, at high temperatures or under certain environments, the oxidation of aluminum nitride may affect its flexural strength.

In summary, the influencing factors of the flexural strength of aluminum nitride substrates mainly include parameters and conditions during the preparation process, microstructure, temperature and chemical properties. In practical applications, the flexural strength of aluminum nitride substrates can be improved by optimizing the preparation process, controlling the microstructure, selecting appropriate temperature and chemical environment according to specific needs and environmental conditions.