A method of forming one or more high temperature co-fired ceramic articles, comprising the steps of:— a) forming a plurality of green compacts, by a process comprising dry pressing a powder comprising ceramic and organic binder to form a green compact; b) disposing a conductor or conductor precursor to at least one surface of at least one of the plurality of green compacts to form at least one patterned green compact; c) assembling the at least one patterned green compact with one or more of the plurality of green compacts or patterned green compacts or both to form a laminated assembly; d) isostatically pressing the laminated assembly to form a pressed laminated assembly; e) firing the pressed laminated assembly at a temperature sufficient to sinter the ceramic layers together.

The invention relates to a copper-ceramic composite comprising:—a ceramic substrate;—a copper or copper alloy coating in which the copper or copper alloy has grain sizes of 10 μm to 300 μm and a number distribution of the grain sizes with a median d.sub.50 and an arithmetic mean d.sub.arith, the ratio of d.sub.50 to d.sub.arith (d.sub.50/d.sub.arith) being between 0.75 and 1.10.

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.

In a ceramic sintered body, the Zr content is 17.5 mass %-23.5 mass % in terms of ZrO.sub.2, the Hf content is 0.3 mass %-0.5 mass % in terms of HfO.sub.2, the Al content is 74.3 mass %-80.9 mass % in terms of Al.sub.2O.sub.3, the Y content is 0.8 mass %-1.9 mass % in terms of Y.sub.2O.sub.3, the Mg content is 0.1 mass %-0.8 mass % in terms of MgO, the Si content is 0.1 mass %- and 1.5 mass % in terms of SiO.sub.2, and the Ca content is 0.03 mass %-0.35 mass % in terms of CaO. The total content of Na and K is 0.01 mass %-0.10 mass %, when the K content is converted to K.sub.2O and the Na content is converted to Na.sub.2O. The balance content is 0.05 mass % or less in terms of oxide.

The invention relates to a copper/ceramic composite comprising—a ceramic substrate which contains aluminum oxide, —a coating which lies on the ceramic substrate and which is made of copper or a copper alloy, wherein the copper or the copper alloy has a particle size number distribution with a median value d.sub.50, an arithmetic mean value d.sub.arith, and a symmetry value S(Cu)=d.sub.50/d.sub.arith; the aluminum oxide has a particle size number distribution with a median value d.sub.50, an arithmetic mean value d.sub.arith, and a symmetry value S(Al.sub.2O.sub.3)=d.sub.50/d.sub.arith; and S(Al.sub.2O.sub.3) and S(Cu) satisfy the following condition: 0.7≤S(Al.sub.2O.sub.3)/S(Cu)≤1.4.

The invention relates to a copper-ceramic composite comprising: a ceramic substrate; and a copper or copper alloy coating on the ceramic substrate, the copper or copper alloy having grain sizes of 10 μm to 300 μm.

In a copper-ceramic bonded body of the present invention, at a bonding interface of a copper member and a ceramic member, there are formed a nitride compound layer containing one or more nitride forming elements selected from Ti, Nb, Hf, and Zr, and an Ag—Cu eutectic layer, in order from the ceramic member side, the thickness of the nitride compound layer is 0.15 μm or more and 1.0 μm or less, an intermetallic compound phase formed of an intermetallic compound that contains the nitride forming element and Si is present between the copper member and the ceramic member, and Cu and Si are present at the grain boundary of the nitride compound layer.

An electrical termination unit or feedthrough which may be used for routing electrical conductors through a chamber wall, or otherwise across a barrier between isolated atmospheric conditions. The electrical termination unit may have aluminum as the interface material to the chamber interface and may utilize a ceramic insulator. The electrical termination unit may have the aluminum used as the interface brazed directly to a ceramic surface of the insulator. The aluminum that forms the chamber interface may be formed within a hollow ceramic tube in the same process step that brazes the aluminum to the ceramic tube with a hermetic joint. Machining subsequent to the brazing of the aluminum to the ceramic insulator may allow for achievement of the final form desired. A method for manufacturing such an electrical termination unit.

A direct bonded copper ceramic substrate is provided, which includes a nitride ceramic substrate, a first passivation layer, and a first copper layer. The first passivation layer includes aluminum oxide or silicon oxide doped with another metal. The other metal is titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, or a combination thereof. The aluminum or silicon and the other metal have a weight ratio of 60:40 to 99.5:0.5. The first passivation layer is disposed between the top surface of the nitride ceramic substrate and the first copper layer.

The present invention relates to a copper ceramic substrate incorporating a ceramic carrier, and a copper layer joined to a surface of the ceramic carrier, wherein the copper layer incorporates at least one first layer, which faces the ceramic carrier and has an average first grain size, and a second layer, which is arranged on the face of the copper layer facing away from the ceramic carrier and has an average second grain size, the second grain size being smaller than the first grain size.