Insulating properties of heat dissipation substrates (Al2O3 on Al) fabricated by aerosol deposition method

Much attention has been paid for heat dissipation ceramic substrates with a high thermal conductivity such as direct brazed aluminum (DBA) substrates and multilayer wiring substrates based on a low temperature co-fired ceramics (LTCC) processing, which are applied for insulated gate bipolar transistor (IGBT) modules of hybrid automobiles and heat dissipation substrates of LED array illumination. In general, sintered bulks are used for these insulating layers in DBA substrates. An aerosol deposition (AD) method based on an impact adhesion of the fine particles for forming of thick ceramic layers can be deposited ceramic thick films on metal substrates (e.g. Al, Cu) directly because of room temperature process. Since it is easy to obtain thick ceramic layers (thickness of > 1 μm) with a high insulating properties on metal substrates, high performance heat dissipation substrates with thinned insulating layer are expected to be created by using the AD method. In this study, Al2O3 dense ceramic films with thic...