Aluminium Nitride – Superior Thermal Conductivity for Electronics

Aluminum nitride boasts superior electrical and thermal insulation properties, making it a popular alternative to beryllium oxide in high power electronic applications. Machinable using conventional methods without health concerns.

AlN is known for its wurtzite crystal structure that features spontaneous polarization that improves its electrical and mechanical characteristics, while its ionic character contributes to excellent chemical corrosion resistance.

Thermal Conductivity

Aluminum nitride boasts excellent thermal conductivity, making it an excellent material choice for applications requiring rapid heat dissipation. Furthermore, its non-toxic nature, low thermal expansion rate and ability to be metallised makes aluminum nitride suitable for many electrical applications.

AlN is known for its superior thermal conductivity due to its small atomic size, strong interatomic bonds and simple crystal structure. Furthermore, its broken inversion symmetry along the polar direction allows fabrication on metal-polar or nitrogen-polar substrates without needing intentional doping.

AlN’s performance depends on both its purity level and impurities found during deposition; generally speaking, higher purity levels result in improved thermal conductivity. Additionally, substrate quality and secondary phase presence also play a factor in thermal conductivity of thin films and devices as voids and defects can impede heat transfer and diminish effective conductivity.

Electrical Insulation

Aluminium nitride’s combination of high thermal conductivity and electrical insulation properties make it an ideal material for electronics use, from substrates for semiconductors to heatsinks for LED lighting technology or high-powered electronics components.

Aluminum nitride’s strength lies in its stability, which makes it an invaluable material in electronics manufacturing. It resists attacks from most etching acids and can be easily machined; in addition, its thin film formation properties make it ideal for microelectromechanically coupled devices (MEMS).

However, AlN powder can be susceptible to hydrolysis reactions in humid environments, leading to aluminum oxide formation that damages ceramic surfaces if present. This can often be mitigated by coating AlN powder with a binder which prevents it from reacting with water in these humid conditions; Longo et al. [24] performed dispersion studies using sonication technology on both spherical and fibrous alumina nanoparticles in aqueous EG solutions.

Thermal Stability

Aluminium nitride’s combination of thermal conductivity and electrical insulation properties make it an ideal material for electronics such as power electronics and optoelectronic devices, due to its molecular chemical formula and hexagonal lattice structure.

Aluminum nitride is transparent to UV light and boasts a bandgap energy of 6eV, making it suitable for UVC LEDs. Furthermore, its low coefficient of thermal expansion prevents damage by plasma.

This research seeks to enhance the thermal conductivity of polycrystalline aluminium nitride by adding graphene particles to its matrix. Graphene was distributed using hot pressing at 1900 degC with uniaxial pressure to orient its particle alignment with heat flow direction, with significant results that demonstrate its increased thermal conductivity.

Mechanical Stability

Aluminium Nitride is a non-toxic material that can withstand extreme temperature environments while offering excellent mechanical stability. Furthermore, its low coefficient of thermal expansion makes it suitable for PCBs that require components to be separated without creating strain on components that need to be separated from each other without creating undue stress on components.

Aluminum nitride’s ability to efficiently dissipate heat and provide electrical insulation makes it an ideal substrate for high-power semiconductor devices with high frequencies, such as LEDs or laser diodes, where efficient thermal management is critical to performance and longevity.

This non-toxic material can be machined into complex shapes when in its green or biscuit forms, however for full densification of its body it requires sintering to fully densify. Sintering results in dense aluminium nitride structures which are chemically and mechanically stable – the chart below provides more details regarding their relative properties compared with non-oxide engineering ceramics.