Abstract: A bonded assembly according to the present embodiment, includes a metal plate and a ceramic substrate bonded to each other through a bonding layer containing Ag. In the bonded assembly, in a measurement region that is formed in a cross section formed by a thickness direction of the bonding layer and an orthogonal direction thereto, and that has a size of a length in the thickness direction of the bonding layer×a length of 200 ?m in the orthogonal direction, a Ag-rich region having a Ag concentration of 60 at % or more has an area ratio of 70% or less to a Ag-poor region having a Ag concentration of 50 at % or less.

Abstract: The present invention provides a ceramic circuit board comprising: a ceramic substrate; and at least one of a recess and a through-hole formed in the ceramic substrate, wherein a conductive portion filled with a conductor is provided in the recess or the through-hole, the surface roughness Ra is 1.0 ?m or less, and the maximum height Rz is 100 ?m or less. It is preferable that the maximum height Rz is 10 ?m or less. Further, it is preferable that the surface roughness Ra is 0.5 ?m or less. According to the above-described configuration, it is possible to provide a ceramic circuit board having an excellent positionability of the conductive portion for mounting a semiconductor element.

Abstract: The present invention provides a ceramic circuit board comprising: a ceramic substrate; and at least one of a recess and a through-hole formed in the ceramic substrate, wherein a conductive portion filled with a conductor is provided in the recess or the through-hole, the surface roughness Ra is 1.0 ?m or less, and the maximum height Rz is 100 ?m or less. It is preferable that the maximum height Rz is 10 ?m or less. Further, it is preferable that the surface roughness Ra is 0.5 ?m or less. According to the above-described configuration, it is possible to provide a ceramic circuit board having an excellent positionability of the conductive portion for mounting a semiconductor element.