Technical ceramic with ultra-high thermal conductivity and electrical insulation.
Core Principles & Analysis
Its wurtzite lattice conducts heat at up to about 285 W/m·K in polycrystalline form — roughly ten times alumina — while remaining an excellent electrical insulator.
Its strongly covalent bonding resists densification, so it is sintered near 1,800 °C with yttria or other oxide additives.
Thin piezoelectric AlN films form the bulk-acoustic-wave (FBAR) filters that separate radio bands in virtually every smartphone.