With the advent of the information technology revolution, the integrated circuit industry is developing rapidly. The increase in system integration will lead to higher power density, as well as increased heat generated by electronic components and systems. Therefore, effective electronic packaging must address the heat dissipation problem of electronic systems.
In this context, ceramic substrates, due to their excellent heat dissipation performance, have seen a rapid surge in demand, particularly aluminum nitride ceramic substrate. Packaging substrates primarily utilize the material’s high thermal conductivity to transfer heat from the chip (the heat source) and facilitate heat exchange with the external environment. For power semiconductor devices, the packaging substrate must meet the following requirements:
- High thermal conductivity to meet the heat dissipation needs of the device.
- Good thermal resistance to withstand high-temperature applications (above 200°C) of power devices.
- Matching of thermal expansion coefficients to reduce thermal stress in the packaging, which is essential for compatibility with chip materials.
- Low dielectric constant, good high-frequency characteristics, reducing signal transmission time, and improving signal transmission speed.
- High mechanical strength to meet the mechanical performance requirements of the device during packaging and application.
- Good corrosion resistance to withstand strong acids, strong alkalis, boiling water, organic solvents, and other corrosive substances.
- Dense structure to meet the hermetic sealing requirements for electronic devices.
How does aluminum nitride perform? As a ceramic substrate material, below is aluminum nitride's characteristics:
- High Thermal Conductivity: The theoretical thermal conductivity of aluminum nitride can reach up to 320 W/(m·K) at room temperature, which is 8 to 10 times higher than that of alumina ceramics. The actual thermal conductivity in production can be as high as 200 W/(m·K), which is beneficial for heat dissipation in LEDs and improving LED performance.
- Low Thermal Expansion Coefficient: The theoretical value is 4.6 × 10^-6/K, which is close to the thermal expansion coefficients of commonly used LED materials such as Si and GaAs. The change pattern of aluminum nitride’s thermal expansion coefficient is also similar to that of Si. Additionally, aluminum nitride matches well with the GaN crystal lattice. Thermal and lattice matching helps ensure a good connection between the chip and substrate during the fabrication of high-performance high-power LEDs, which is crucial for their performance.
- Good Insulation Properties: Aluminum nitride has a wide bandgap of 6.2 eV and excellent insulation properties, making it unnecessary to perform insulation treatment when used in high-power LEDs, simplifying the process.
- High Hardness and Strength: Aluminum nitride has a wurtzite structure with strong covalent bonds, giving it high hardness and strength. Moreover, it has good chemical stability and high-temperature resistance. It remains stable at temperatures up to 1000°C in air and can maintain good stability in a vacuum at temperatures up to 1400°C, making it suitable for sintering at high temperatures. Its corrosion resistance meets the requirements for subsequent processes.
Based on the above characteristics, aluminum nitride features high thermal conductivity, high strength, high resistivity, low density, low dielectric constant, non-toxicity, and a thermal expansion coefficient that is compatible with Si, making it an excellent and promising ceramic substrate material.
China Aluminum Nitride Manufacturer:Xiamen Juci Technology Co.,Ltd
Website:www.jucioversea.com