Aluminum nitride is a typical third-generation semiconductor material. It has an extremely wide bandgap and very large exciton binding energy. The bandgap width is 6.2eV, which is a direct bandgap semiconductor. Because aluminum nitride has many outstanding excellent physical properties, such as high breakdown field strength, thermal conductivity, resistivity, etc., it has always attracted much attention in the semiconductor field and is also a material that has been “conquered” in the semiconductor field.
Performance characteristics of aluminum nitride
Aluminum nitride is a crystal based on covalent bonds. It belongs to hexagonal diamond-like nitride. Its theoretical density is 3.26g/cm3, Mohs hardness is 7~8, and its strength at room temperature is high, and its strength will decrease slowly with the increase of temperature.
Compared with several other ceramic materials, aluminum nitride has excellent comprehensive properties, especially its excellent thermal conductivity. It is very suitable for semiconductor substrates and structural packaging materials, and its application potential in the electronics industry is very huge.
In the application of electronic devices, heat dissipation is a key point to consider when developing devices. Theoretically, the thermal conductivity of AlN can reach 320W·m-1·K-1, which is an ideal heat dissipation material. The purity of AlN powder has a great influence on its thermal conductivity. It is no exaggeration to say that for every 1% increase in the purity of AlN, its thermal conductivity can be increased by 30%. The high thermal conductivity is an advantage and a difficulty for AlN.
The thermal conductivity of AlN is affected by factors such as raw material purity and the sintering process. In practice, due to the impurities and defects in AlN, the thermal conductivity of the product is lower than the theoretical value. In terms of AlN single crystal growth, impurities (especially oxygen and carbon) in the raw materials will be deposited inside the single crystal and form various defects, affecting the quality and properties of the crystal. Among them, the oxygen element has a strong affinity with AlN and is easy to enter the AlN lattice to form defects, becoming the main factor in reducing the thermal conductivity of the material. These factors make aluminum nitride not easy to “conquer”.
Non-Ferrous Crucible Inc. provides customers with excellent-performance aluminum nitride products through a variety of molding and processing methods, which are widely used in electronic packaging, semiconductors, and other fields.