As a result, in order to make the insulating
ceramic substrate, it is required to have high heat conduction rates and mechanical strength. As a material for insulating ceramic substrates, it can be listed, such as aluminum nitride and silicon nitride, but for the insulation
ceramic substrate using aluminum nitride, because the heat conduction rate is high but the mechanical strength is low, it is easy to produce such cracks. The power semiconductor module for this type of structure that is used to apply a large stress on the ceramic substrate. Therefore, in the following patent literature 1, an instance of silicon nitride plate is publicly publicized to reduce the ratio of glass phase with low thermal conduction rate and increase the thermal conductivity of the silicon nitride plate with low thermal conduction rate. The following is the first -known example of this technique;
In addition, in the following patent literature 2, instances of silicon nitride ceramic materials are publicly publicly disclosed to make intrinsicization of the crystal realm, so as to make silicon nitride grains more firmly combined through the intra -lens crystal phase. To improve intensity. The technology is the second known example; in addition, in the following patent literature 3, an instance of the publication of silicon -nitride heat dissipation components is publicly publicly available. Silicon -nitride heat dissipation parts. The technology is the third -known example; in addition, in the following patent literature 4, there are examples of silicon nitride sintering body. Stir -of -sarcasm with excellent impact.