A heat sink-attached power module substrate board has a ratio (A1t111)/{(A2t222)+(A3t333)} 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, 1 (N/mm.sup.2) is yield strength, and 1 (/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, 2 (N/mm.sup.2) is yield strength, and 2 (/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, 3 (N/mm.sup.2) is yield strength, and 3 (/K) is a linear expansion coefficient, all of the heat sink.

The present invention provides a metal-ceramic base material and the like which allow a ceramic base material and a desired metal material to be easily joined. A metal-ceramic base material (30) to be joined to a metal material (40), includes: a ceramic base material (20); and a metal film (25) provided on the ceramic base material (20), the metal film (25) being formed by thermal spray of a mixed powder material containing aluminum, alumina, and nickel, at least part of the nickel being exposed on a surface of the metal film (25).

A method of preparing a substrate having a wetting surface, including confirming the presence of an open, interconnected pore network in a ceramic substrate to be wetted with a first metal, filling the open, interconnected pore network with a second metal, exuding the second metal to coat the surface of the substrate, and wetting the substrate with the first metal. The ceramic substrate is not decomposed by the first metal and the ceramic substrate is not decomposed by the second metal.

An insulated circuit board having a ceramic substrate, a circuit layer on which a circuit pattern is formed and that is bonded to one surface of the ceramic substrate, and a metal layer bonded to the other surface of the ceramic substrate. The circuit layer has a first circuit layer that is bonded to the ceramic substrate and is made of aluminum and a second circuit layer that is bonded to the upper surface of the first circuit layer and is made of copper, the metal layer has a first metal layer that is bonded to the ceramic substrate and is made of aluminum and a second metal layer that is bonded to the upper surface of the first metal layer and is made of copper, and the thicknesses of the first circuit layer and the first metal layer are each 0.2 mm or more and 0.9 mm or less.

An assembly includes a first member, a second member adjacent to the first member, and an aluminum material. At least one of the first member and the second member defines at least one trench. The aluminum material is disposed within the trench and bonds the first member to the second member along adjacent faces. In one form, a spacing between the first member and the second member along the adjacent faces is less than 5 m.

The present invention provides a ceramic metal circuit board including a ceramic substrate and metal plates bonded to both surfaces of the ceramic substrate through respective bonding layers, wherein a metal film is provided on a surface of one metal plate bonded to one surface of the ceramic substrate; and at least a part of another metal plate bonded to another surface of the ceramic substrate is not provided with the metal film. Preferably, a protruding portion is formed as a portion of the bonding layer so as to protrude from a side surface of each of the metal plates. According to the above-described configuration, it is possible to provide a ceramic circuit board which is easy to use according to the parts to be bonded and is excellent in heat-cycle resistance characteristics.

A method for producing a metal-ceramic substrate with electrically conductive vias includes: attaching a first metal layer in a planar manner to a first surface side of a ceramic layer; after attaching the first metal layer, introducing a copper hydroxide or copper acetate brine into holes in the ceramic layer delimiting a via, to form an assembly; converting the copper hydroxide or copper acetate brine into copper oxide; subjecting the assembly to a high-temperature step above 500 C. in which the copper oxide forms a copper body in the holes; and after converting the copper hydroxide or copper acetate brine into the copper oxide, attaching a second metal layer in a planar manner to a second surface side of the ceramic layer opposite the first surface side. The copper body produces an electrically conductive connection between the first and the second metal layers.

A method and structure for a bonding layer are disclosed. The bonding structure includes a first portion surrounding an opening in a body defining a dam thereabout. A second portion surrounds the first portion. The first portion is formed from a material resistant to degradation from exposure to a process gas. The second portion is formed from a different material than the material of the first portion. The first portion further includes one or more additives to change properties thereof.

A bonded body of copper and ceramic includes: a copper member made of copper or a copper alloy and a ceramic member made of an aluminum oxide, the copper member and the ceramic member being bonded to each other; a magnesium oxide layer which is formed on a ceramic member side between the copper member and the ceramic member; and a Mg solid solution layer which is formed between the magnesium oxide layer and the copper member and contains Mg in a state of a solid solution in a Cu primary phase, in which one or more active metals selected from Ti, Zr, Nb, and Hf are present in the Mg solid solution layer.

An electrostatic chuck with a top surface adapted for Johnsen-Rahbek clamping in the temperature range of 500 C to 750 C. The top surface may be sapphire. The top surface is attached to the lower portion of the electrostatic chuck using a braze layer able to withstand corrosive processing chemistries. A method of manufacturing an electrostatic chuck with a top surface adapted for Johnsen-Rahbek clamping in the temperature range of 500 C to 750 C