A joining layer of a joined body includes a joining material which contains, as a main component, a metal having a surface tension of 1000 mN/m or less at its melting point, and a metal layer which has a plurality of pores formed therein and in which at least some of the pores are impregnated with the joining material.

The present invention relates to a method for producing a metal-ceramic substrate (1) comprising: —providing a ceramic element (30) and at least one metal layer (10), wherein the ceramic element (30) and the at least one metal layer (10) extend along a main extension plane (HSE), —joining the ceramic element (30) to the at least one metal layer (10) to form a metal-ceramic substrate (1), in particular by means of a direct metal joining method, a hot isostatic pressing method and/or a soldering method, and —machining the at least one metal layer (10) by means of a machine tool (40) and/or laser light in order to define a geometry, at least in some portions, of a side face (15) of the at least one metal layer (10) not running parallel to the main extension plane (HSE).

The invention relates to a process for producing a metal-ceramic substrate (1), comprising: —providing a ceramic element (10), a metal ply (40) and at least one metal layer (30), —forming an ensemble (18) of the ceramic element (10), the metal ply (40) and the at least one metal layer (30), —forming a gas-tight container (30) surrounding the ceramic element (10), wherein the at least one metal layer (30) is arranged between the ceramic element (10) and the metal ply (40) in the container, and—forming the metal-ceramic substrate (1) by hot isostatic pressing.

A method includes applying a sintering precursor material layer to each of a first surface and a second surface of a ceramic tile, and assembling a precursor assembly of a direct bonded copper (DBC) substrate by coupling a first leadframe on the sinter precursor material layer on the first surface of the ceramic tile and a second leadframe on the second surface of the sinter precursor material layer on a second surface of the ceramic tile such that the ceramic tile is disposed between the first leadframe and the second leadframe. The method further includes sinter bonding the first leadframe and the second leadframe to the ceramic tile to form a sinter bonded DBC substrate.

A metal-ceramic substrate (1) comprising an insulating layer (11) comprising a ceramic and having a first thickness (D1), and a metallization layer (12) bonded to the insulation layer (11) and having a second thickness (D2),
wherein the first thickness (D1) is less than 250 μm and the second thickness (D2) is greater than 200 μm and wherein the first thickness (D1) and the second thickness (D2) are dimensioned such that a ratio of an amount of the difference between a thermal expansion coefficient of the metallization layer (12) and a thermal expansion coefficient of the metal-ceramic substrate (1) to a thermal expansion coefficient of the metal-ceramic substrate (1)
has a value less than 0.25, preferably less than 0.2 and more preferably less than 0.15 or even less than 0.1.

A bonded body of the present invention includes a ceramic member formed of ceramics and a Cu member formed of Cu or a Cu alloy. In a bonding layer formed between the ceramic member and the Cu member, an area ratio of a Cu.sub.3P phase in a region extending by up to 50 μm toward the Cu member side from a bonding surface of the ceramic member is equal to or lower than 15%.

A power-module substrate and a heat sink made of an aluminum-impregnated silicon carbide formed by impregnating aluminum in a porous body made of silicon carbide; where yield strength of a circuit layer is σ1 (MPa), a thickness of the circuit layer is t1 (mm), a bonding area of the circuit layer and a ceramic board is A1 (mm.sup.2), yield strength of a metal layer is σ2 (MPa), a thickness of the metal layer is t2 (mm), a bonding area of the metal layer and the ceramic board is A2 (mm.sup.2); the thickness t1 is formed to be between 0.1 mm and 3.0 mm (inclusive); the thickness t2 is formed to be between 0.15 mm and 5.0 mm (inclusive); the thickness t2 is formed larger than the thickness t1; and a ratio {(σ2×t2×A2)/(σ1×t1×A1)} is in a range between 1.5 and 15 (inclusive).

A DBC substrate for power semiconductor devices includes a ceramic workpiece of a non-oxide ceramic having first and second opposing main sides, the ceramic workpiece having a thickness of 10 μm or more measured between the first and second main sides, a copper-containing layer disposed over the first main side, the copper-containing layer having a thickness of 5 μm or more, and an intermediate layer comprising Al.sub.2O.sub.3 disposed between the ceramic workpiece and the copper-containing layer.

A bonded body of the present invention includes a ceramic member formed of ceramics and a Cu member formed of Cu or a Cu alloy. In a bonding layer formed between the ceramic member and the Cu member, an area ratio of a Cu.sub.3P phase in a region extending by up to 50 μm toward the Cu member side from a bonding surface of the ceramic member is equal to or lower than 15%.

The present application relates to a method of laser ablation of a metal-ceramic substrate, in which a laser is used under process conditions in which the formation of solid metal particles on the metal-ceramic substrate, which can separate from metal particles released by laser ablation near the ablation edge, is essentially avoided. Further the present application relates to a ceramic-metal substrate comprising a ceramic substrate and a metallization on at least one side of the ceramic substrate, wherein the ceramic substrate and the metallization have flush cutting edge.