Нитрида алюминия

Химические свойства

Crystalline solid.

Физические свойства

Insulator (E_g =4.26 eV).  Decomposes with water, acids, and alkalis to Al(OH)₃ and NH₃. Crucible container for GaAs crystal growth

Характеристики

Aluminum nitride is an excellent substrate for creating wide-band-gap semiconductors for wireless communications and power-industry applications. Since aluminum nitride withstands very high temperatures, this substrate material can be used for microelectronic devices on jet engines. Such substrates also would improve the production of blue and ultraviolet lasers that could be used to squeeze a full-length movie onto a CD. Aluminum nitride crystals have also been grown in a tungsten crucible at 2300°C.

Использование

Aluminum nitride possesses very high thermal conductivity and effectively used in the ceramic industry. It finds application in deep ultraviolet optoelectronics, steel production, dielectric layers in optical storage media, chip carriers and as a crucible to grow crystals of gallium arsenide. It is also used as a radio frequency filter, which finds application in mobile phones. Further, it is used as a circuit carrier in semiconductors. In addition to this, it is used as a heat-sink in light-emitting diode lighting technology.

Подготовка

Aluminum nitride is conveniently prepared by an electric arc between aluminum electrodes in a nitrogen atmosphere. Crucibles of the pressed powder, sintered at 1985°C, are resistant to liquid aluminum at 1985°C, to liquid gallium at 1316°C, and to liquid boron oxide at 1093°C. Aluminum nitride has good thermal shock resistance and is only slowly oxidized in air (1.3% converted to Al2O3 in 30 h at 1427°C). It is inert to hydrogen at 1705°C but is attacked by chlorine at 593°C.

Промышленное использование

Aluminum nitride is an excellent substrate for creating wide-band-gap semiconductors for wireless communications and power-industry applications. Since aluminum nitride withstands very high temperatures, this substrate material can be used for microelectronic devices on jet engines. Such substrates also would improve the production of blue and ultraviolet lasers that could be used to squeeze a full-length movie onto a CD. Aluminum nitride crystals have also been grown in a tungsten crucible at 2300 C.

Использование в материалах

Aluminum nitride (AlN) has an unusual combination of properties: it is an electrical insulator, but an excellent conductor of heat. This is just what is wanted for substrates for high-powered electronics; the substrate must insulate yet conduct the heat out of the microchips. This, and its high strength, chemical stability, and low expansion give it a special role as a heat sinks for power electronics. Aluminum nitride starts as a powder, is pressed (with a polymer binder) to the desired shape, then fired at a high temperature, burning off the binder and causing the powder to sinter.
Aluminum nitride is particularly unusual for its high thermal conductivity combined with a high electrical resistance, low dielectric constant, good corrosion, and thermal shock resistance.
Typical uses. Substrates for microcircuits, chip carriers, heat sinks, electronic components; windows, heaters, chucks, clamp rings, gas distribution plates.