Heat radiation member
A heat radiation member excellent in electrical insulation and better in thermal conduction is provided. The heat radiation member includes a substrate composed of a composite material containing diamond and a metallic phase, an insulating plate provided on at least a part of front and rear surfaces of the substrate and composed of an aluminum nitride, and a single bonding layer interposed between the substrate and the insulating plate, the heat radiation member having thermal conductivity not lower than 400 W/m·K.
1. A heat radiation member for a semiconductor element comprising:
a substrate composed of a composite material containing diamond and a metallic phase;
an insulating plate provided on a surface of the substrate and composed of aluminum nitride; and
a single bonding layer formed on the surface of the substrate, interposed between the substrate and the insulating plate,
wherein a constituent metal of the metallic phase is pure silver or a silver-based alloy,
the bonding layer is composed of an alloy containing Ag, Cu, and Ti, and
a concentration of the Ti in the bonding layer is not lower than 40 atomic % and not higher than 95 atomic % with a total amount of Ag, Cu, and Ti being defined as 100 atomic %.
2. The heat radiation member according to claim 1 , wherein
the bonding layer is composed of an alloy containing Ti and a main metal element that makes up the metallic phase.
3. The heat radiation member according to claim 1 , wherein the bonding layer comprise a brazing material composed of a silver-based alloy based on the eutectic alloy of Ag and Cu and containing Ti.
4. The heat radiation member according to claim 3 , the concentration of Ti is not lower than 0.5 atomic % and not higher than 3.0 atomic % with the total amount of Ag, Cu, and Ti being defined as 100 atomic %.