Abstract
In the power module products, insulated materials, such as the insulated sheet used for them, are asked for high heat dissipation along with achievement of downsizing and high efficiency of the electronic equipment. In this paper, the details of research about the high heat dissipation organic / inorganic composite material based on the thermosetting resin are introduced. In order to raise thermal conductivity to the thermosetting resin like the epoxy resin, composite with high heat conduction ceramic, such as boron nitride (BN), is investigated. However, even if highly filled up with flake-like BN particles, the great improvement in the thermal conductivity of the thickness direction of the insulating sheet is not obtained because BN particles orient in the direction of a field. On the other hand, if orientation of BN particles is controlled by blending the aggregated BN filler, the thermal conductivity of the thickness direction can be greatly improved with lower filler content. The value of thermal conductivity is 18W/(m・K), and attained the thermal conductivity of the ceramic material level. The technology for improving the thermal conductivity of the epoxy resin also progresses, and development of the organic / inorganic composite material which has a higher thermal conductivity is expected in future.
