Aluminium Nitride - Applications

Applications

Metallization methods are available to allow AlN to be used in electronics applications similar to those of alumina and beryllium oxide.

Currently there is much research into developing light-emitting diodes to operate in the ultraviolet using the gallium nitride based semiconductors and, using the alloy aluminum gallium nitride, wavelengths as short as 250 nm have been achieved. In May 2006, an inefficient AlN LED emission at 210 nm has been reported.

Among the applications of AlN are

• opto-electronics,
• dielectric layers in optical storage media,
• electronic substrates, chip carriers where high thermal conductivity is essential,
• military applications,
• as a crucible to grow crystals of gallium arsenide,
• steel and semiconductor manufacturing.

Epitaxially grown thin film crystalline aluminium nitride is also used for surface acoustic wave sensors (SAW's) deposited on silicon wafers because of the AlN's piezoelectric properties. One application is an RF filter used in mobile phones called a thin film bulk acoustic resonator (FBAR). This is a MEMS device that uses aluminium nitride sandwiched between two metal layers.