The performance of electronic devices mounted on aluminum nitride

The thermal and electrical performance of test circuits built with aluminum nitride ceramic substrates is considered. The power device tested was a low-resistivity power resistor network, which models fairly well most electronic devices that are uniformly generating heat. Identical circuits made of beryllia, alumina, and aluminum nitride were constructed for comparison. The test circuits were profiled using a noncontact thermal imaging system at both room temperature and elevated temperatures. Although the beryllia test circuits showed marginally better thermal dissipation at room temperature, the aluminum nitride circuit was a virtual equivalent heat sink at higher temperatures. The consistency of the aluminum nitride heat sink behavior at low- and high-temperature conditions will help to prevent the thermal runaway that can develop with beryllia based circuits. Thus the aluminum nitride heat sink improves circuit performance and reliability compared to the currently used ceramic materials