Abstract: A bonded body according to an embodiment includes a substrate, a metal member, and a bonding layer. The bonding layer is provided between the substrate and the metal member. The bonding layer includes a first particle including carbon, a first region including a metal, and a second region including titanium. The second region is provided between the first particle and the first region. A concentration of titanium in the second region is greater than a concentration of titanium in the first region.

Abstract: A bonded body according to an embodiment includes a ceramic substrate, a copper plate, and a bonding layer. The bonding layer is located on at least one surface of the ceramic substrate and bonds the ceramic substrate and the copper plate. The bonding layer includes Ag and Ti. The copper plate includes a first region, a second region, and a third region. The first region is separated from the bonding layer in a thickness direction. The second region is located between the bonding layer and the first region and has a higher Ag concentration than the first region. The third region is located between the bonding layer and the second region and has a lower Ag concentration than the second region.

Abstract: According to the embodiment, a bonded body includes a ceramic substrate, a copper plate. A bonding layer is located on at least one surface of the ceramic substrate. The bonding layer bonds the ceramic substrate and the copper plate. The bonding layer includes a Ti reaction layer including titanium nitride or titanium oxide as a major component, and a plurality of first alloys positioned between the Ti reaction layer and the copper plate. Each of the plurality of first alloys includes at least one selected from a Cu—Sn alloy and a Cu—In alloy. The first alloys have mutually-different Sn concentrations or In concentrations. According to the embodiment, a warp amount can be reduced. A heating rate and a cooling rate in the bonding process can be increased. According to the embodiment, a silicon nitride substrate is favorable for the ceramic substrate.

Abstract: A bonded body according to an embodiment comprises a ceramic substrate, a copper plate, and a bonding layer provided on at least one surface of the ceramic substrate and bonding the ceramic substrate and the copper plate, in which the bonding layer contains Cu, Ti, and a first element being one or two selected from Sn and In, and the bonding layer includes a Ti-rich region in which a ratio (MTi/ME1) of a mass MTi of Ti to a mass ME1 of the first element being 0.5 or more and a Ti-poor region in which the ratio (MTi/ME1) being 0.1 or less.

Abstract: A bonded body according to an embodiment comprises a ceramic substrate, a copper plate, and a bonding layer provided on at least one surface of the ceramic substrate and bonding the ceramic substrate and the copper plate, in which the bonding layer contains Ag, Cu, Ti, and a first element being one or two selected from Sn and In, a Ti alloy of Ti and at least one selected from Ag, Cu, Sn, and In existing at a bonding boundary between the copper plate and the bonding layer, and the Ti alloy existing over not less than 30% per a length of 30 ?m at the bonding boundary.

Abstract: A bonded body according to an embodiment includes a ceramic substrate, a copper plate, and a bonding layer that is located on at least one surface of the ceramic substrate and bonds the ceramic substrate and the copper plate. The bonding layer includes titanium. The bonding layer includes first and second regions; the first region includes a layer including titanium as a major component; the layer is formed at an interface of the bonding layer with the ceramic substrate; and the second region is positioned between the first region and the copper plate. The bonded body has a ratio M1/M2 of a titanium concentration M1 at % in the first region and a titanium concentration M2 at % in the second region that is not less than 0.1 and not more than 5 when the Ti concentrations are measured by EDX respectively in measurement regions in the first and second regions.

Abstract: A bonded body includes a ceramic substrate and a copper plate, in which the copper plate is bonded to the ceramic substrate via a bonding layer, the copper plate includes a surface perpendicular to a direction in which the ceramic substrate and the copper plate are bonded, and a number percentage of copper crystal grains having major diameters greater than 400 ?m in three 5 mm×5 mm regions included in the surface is not less than 0% and not more than 5%. The bonding temperature is favorably not more than 800° C. The number percentage of the copper crystal grains having major diameters greater than 400 ?m is favorably not more than 1%.

Abstract: According to one embodiment, when a DSC curve is measured using a differential scanning calorimeter (DSC) for a brazing material for bonding a ceramic substrate and a metal plate, the brazing material has an endothermic peak within a range of not less than 550° C. and not more than 700° C. in a heating process. The brazing material favorably includes Ag, Cu, and Ti. The brazing material favorably has not less than two of the endothermic peaks within a range of not less than 550° C. and not more than 650° C. in the heating process.

Abstract: A bonded body according to an embodiment includes a substrate, a metal member, and a bonding layer. The bonding layer is provided between the substrate and the metal member. The bonding layer includes a first particle including carbon, a first region including a metal, and a second region including titanium. The second region is provided between the first particle and the first region. A concentration of titanium in the second region is greater than a concentration of titanium in the first region.