A metal-ceramic substrate having at least one ceramic layer (2), which is provided on a first surface side (2a) with at least one first metallization (3) and on a second surface side (2b), opposite from the first surface side (2a), with a second metallization (4), wherein the first metallization (3) is formed by a film or layer of copper or a copper alloy and is connected to the first surface side (2a) of the ceramic layer (2) with the aid of a “direct copper bonding” process. The second metallization (4) is formed by a layer of aluminum or an aluminum alloy.

Provided are: an apparatus and a method for producing a (metal plate)-(ceramic board) laminated assembly, a bonding material and a metal plate during the bonding of the metal plate to the ceramic board through the bonding-material layer and an apparatus and a method for producing a power-module substrate. An apparatus for producing a (metal plate)-(ceramic board) laminated assembly by laminating a metal plate having a temporary bonding material formed thereon on a ceramic board having a bonding-material layer formed thereon, the apparatus being equipped with: a conveying device which conveys the metal plate onto the ceramic board to laminate the ceramic board and the metal plate on each other; and a heating device which is arranged in the middle of a passage of the conveyance of the metal plate by the conveying device and melts the temporary-bonding material on the metal plate.

An adapter element (10) for connecting an electronic component (30) to a heat sink element (20), including an insulation layer (15) extending along a main extension plane (HSE), and at least a first web element (11) and a second web element (12), which are arranged next to each other in a direction parallel to the main extension plane (HSE), forming a free area (13), which, in the assembled state, are arranged between the insulating layer (15) and the electronic component (30) in a direction running perpendicular to the main extension plane (HSE), and on whose front sides (18) facing away from the insulating layer (15) the electronic component (30) is arranged in the assembled state, wherein a distance (A) between the first web element (11) and the second web element (12), measured in a plane parallel to the main extension plane (HSE), is smaller than 350 μm.

A power module substrate includes a circuit layer, an aluminum layer arranged on a surface of an insulation layer, and a copper layer laminated on one side of the aluminum layer. The aluminum layer and the copper layer are bonded together by solid phase diffusion bonding.

The present invention is a bonded body in which an aluminum member constituted by an aluminum alloy, and a metal member constituted by copper, nickel, or silver are bonded to each other. The aluminum member is constituted by an aluminum alloy in which a solidus temperature is set to be less than a eutectic temperature of a metal element that constitutes the metal member and aluminum. A Ti layer is formed at a bonding portion between the aluminum member and the metal member, and the aluminum member and the Ti layer, and the Ti layer and the metal member are respectively subjected to solid-phase diffusion bonding.

A semiconductor substrate includes a dielectric insulation layer and a first metallization layer attached to the dielectric insulation layer. The dielectric insulation layer includes a first material having a thermal conductivity of between 25 and 180 W/mK, and an insulation strength of between 15 and 50 kV/mm, and an electrically conducting or semiconducting second material evenly distributed within the first material.

A power module substrate includes an insulating substrate and a metal plate. The metal plate is joined to the insulating substrate with a brazing material in between. As to surface roughness of a lateral surface of the metal plate in a thickness direction, the surface roughness of at least a corner part farthest from a center of the metal plate in plan view is larger than the surface roughness of plane parts sandwiching the corner part.

Provided is a method for producing a silicon nitride sintered body including: a step of molding and firing a raw material powder containing silicon nitride, in which an α-conversion rate of the silicon nitride contained in the raw material powder is less than or equal to 30 mass %. A thermal conductivity (at 20° C.) of the silicon nitride sintered body exceeds 100 W/m.Math.K and a fracture toughness (K.sub.IC) is greater than or equal to 7.4 MPa.Math.m.sup.1/2.

A gas plug of the present disclosure is composed of a columnar porous composite in which a plurality of silicon compound phases containing silicon carbide as a main component are connected to each other via a silicon phase having silicon as a main component. The porous composite is housed inside a tubular body made from a dense ceramic.

A heat sink-attached power module substrate board has a ratio (A1×t1×σ1×α1)/{(A2×t2×σ2×α2)+(A3×t3×σ3×α3)} at 25° C. is not less than 0.70 and not more than 1.30, where A1 (mm.sup.2) is a bonding area of a second layer and a first layer composing a circuit layer; t1 (mm) is an equivalent board thickness, σ1 (N/mm.sup.2) is yield strength, and α1 (/K) is a linear expansion coefficient, all of the second layer, where A2 (mm.sup.2) is a bonding area of the heat radiation-side bonding material and the metal layer; t2 (mm) is equivalent board thickness, σ2 (N/mm.sup.2) is yield strength, and α2 (/K) is a linear expansion coefficient, all of the heat radiation-side bonding material, and where A3 (mm.sup.2) is a bonding area of the heat sink and the heat radiation-side bonding material; t3 (mm) is equivalent board thickness, σ3 (N/mm.sup.2) is yield strength, and α3 (/K) is a linear expansion coefficient, all of the heat sink.