A ceramic circuit substrate and power module with excellent heat cycle resistance characteristics, which is formed by bonding a ceramic substrate and a copper plate via a brazing material including Ag, Cu, and an active metal, wherein the bond void fraction is no greater than 1.0% and the diffusion distance of the Ag, which is a brazing material component, is 5-20 μm. Also, a method for manufacturing a ceramic circuit substrate characterized in that the heating time in a temperature range 400-700° C. in a process for raising the temperature to a bonding temperature is 5-30 minutes and bonding is performed by maintaining the bonding temperature at 720-800° C. for 5-30 minutes.

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%.

This copper/ceramic bonded body includes: a copper member made of copper or a copper alloy; and a ceramic member made of silicon nitride, wherein the copper member and the ceramic member are bonded to each other, a Mg—N compound phase extending from a ceramic member side to a copper member side is present at a bonded interface between the copper member and the ceramic member, and at least a part of the Mg—N compound phase enters into the copper member.

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.

The disclosure provides seals for devices that operate at elevated temperatures and have reactive metal vapors, such as lithium, sodium or magnesium. In some examples, such devices include energy storage devices that may be used within an electrical power grid or as part of a standalone system. The energy storage devices may be charged from an electricity production source for later discharge, such as when there is a demand for electrical energy consumption.

A method for producing a gas-tight metal-ceramic join is disclosed. In an embodiment a method includes providing at least one ceramic main body having a first end face and a second end face, applying a metallization to at least a partial region of the end faces of the main body, applying a nickel layer to the metallized partial region of the end faces, applying a brazing paste to the metallized partial region of the first end face and/or the second end face of the main body, drying the brazing paste, and firing the brazing paste.

A multi-layered structural element and a method for producing a multi-layered structural element are disclosed. In an embodiment dielectric green sheets, at least one ply containing an auxiliary material which contains at least one copper oxide and layers containing electrode material are provided and arranged alternately one above another. These materials are debindered and sintered. The copper oxide is reduced to form the copper metal and the at least one ply is degraded during debindering and sintering.

According to one embodiment, a method for manufacturing a ceramic circuit board is disclosed. The ceramic circuit board includes a copper plate bonded to at least one surface of a ceramic substrate via a brazing material layer including Ag, Cu, and a reactive metal. The method includes: preparing a ceramic circuit board in which a copper plate is bonded on a ceramic substrate via a brazing material layer, and a portion of the brazing material layer is exposed between a pattern shape of the copper plate; a first chemical polishing process of chemically polishing the portion of the brazing material layer; and a first brazing material etching process of etching the chemically polished portion of the brazing material layer by using an etchant having a pH of 6 or less and including one type or two types selected from hydrogen peroxide and ammonium peroxodisulfate.

A copper/ceramic bonded body includes: a copper member made of copper or a copper alloy; and a ceramic member made of an aluminum oxide, wherein the copper member and the ceramic member are bonded to each other, a magnesium oxide layer is provided on a ceramic member side of an interface between the copper member and the ceramic member; and a Mg solid solution layer is provided between the magnesium oxide layer and the copper member and contains Mg in a state of a solid solution in a Cu primary phase.