aluminium oxide (Al2O3)

Alumina (Al2O3) is a crystalline ceramic material that is electrically insulating and heat dissipative. The amorphously arranged aluminum oxide crystals have a size of a few nanometers and are compressed into a compact substance.

Alumina belongs to the high-k dielectrics. It has a permittivity of 9 and a band gap of 8.7 electron volts( eV).

Alumina is suitable for high temperatures and is used in applications such as thick film technology, thermal conductive pads, thermistors and printed circuit board technology, for heat dissipation and insulation. The dielectric strength of a 10 µm thin aluminum oxide layer is 500 V.