A method for producing a connection between two surfaces or surface sections of two ceramic parts comprises: provision of a first ceramic part and of a second ceramic part; provision of an active brazing solder material on at least one surface section of at least one of the ceramic parts; and heating the active brazing solder in a vacuum brazing process. The whole active brazing solder material is provided for connecting the first and the second ceramic part by a sputtering method, wherein at least one surface section of at least one of the ceramic parts, preferably of the two ceramic parts, is layered with a layer sequence of individual components of the active brazing solder material, wherein the average strength of the layers of an individual component of the active brazing solder is no more than 0.5%, in particular not more than 0.2%, preferably not more than 0.1% and especially preferably not more than 0.05% of the strength of the joining region.

A method for the joining of ceramic pieces with a hermetically sealed joint comprising brazing a layer of joining material between the two pieces. The ceramic pieces may be aluminum nitride or other ceramics, and the pieces may be brazed with Nickel and an alloying element, under controlled atmosphere. The completed joint will be fully or substantially Nickel with another element in solution. The joint material is adapted to later withstand both the environments within a process chamber during substrate processing, and the oxygenated atmosphere which may be seen within the interior of a heater or electrostatic chuck. Semiconductor processing equipment comprising ceramic and joined with a nickel alloy and adapted to withstand processing chemistries, such as fluorine chemistries, as well as high temperatures.

It is an object of the present invention to obtain a ceramic circuit substrate having high bonding strength, excellent heat cycle resistance, enhanced reliability of operation as an electronic device, and excellent heat dissipation properties. The present invention provides a ceramic circuit substrate in which metal plates, particularly copper plates, and both main surfaces of a ceramic substrate are bonded vial silver-copper brazing material layers. The silver-copper brazing material layers are formed from a silver-copper brazing material including i) 0.3-7.5 parts by mass of carbon fibers, and ii) 1.0-9.0 parts by mass of at least one active metal selected from titanium, zirconium, hafnium, niobium, tantalum, vanadium, and tin; with respect to iii) a total of 100 parts by mass of a) 75-98 parts by mass of silver powder and b) 2-25 parts by mass of copper powder. The carbon fibers having an average length of 15-400 m, an average diameter of 5-25 m and an average aspect ratio of 3-28.

The disclosure describes techniques for forming a surface layer of an article including a CMC using a cast. In some examples, the surface layer includes three-dimensional surface features, which may increase adhesion between the CMC and a coating on the CMC. In some examples, the surface layer may include excess material, with or without three-dimensional surface features, which is on the CMC. The excess material may be machined to remove some of the excess material and facilitate conforming the article to dimensional tolerances, e.g., for fitting the article to another component. The excess material may reduce a likelihood that the CMC (e.g., reinforcement material in the CMC) is damaged by the machining.

This power module substrate includes a copper plate that is formed of copper or a copper alloy and is laminated on a surface of a ceramic substrate 11; a nitride layer 31 that is formed on the surface of the ceramic substrate 11 between the copper plate and the ceramic substrate 11; and an AgCu eutectic structure layer 32 having a thickness of 15 m or less that is formed between the nitride layer and the copper plate.

The invention relates to a method for producing a metal-ceramic substrate including first and second metallizations and at least one ceramic layer incorporated between the first and second metallizations. Advantageously, first and second metal layers and the at least one ceramic layer are stacked superposed, and in such a way that the free edge sections, of the first and second metal layers respectively, project beyond the edges of the at least one ceramic layer and the first and second metal layers are deformed toward each other in the region of the projecting free edge sections and directly connected to each other in order to form a gas-tight, sealed metal container enclosing a container interior for receiving the at least one ceramic layer. Subsequently, the metal layers forming the metal container with the at least one ceramic layer received in the container interior are hot isostatically pressed together in a treatment chamber at a gas pressure between 500 and 2000 bar and at a process temperature between 300 C. and the melting temperature of the metal layers for producing a preferably flat connection of at least one of the metal layers and the at least one ceramic layer, and at least the projecting free edge sections, which are connected to each other, of the metal layers for forming the first and second metallization are subsequently removed.

A pressure measurement cell, comprising: a ceramic measurement membrane and a ceramic counterpart. The measurement membrane is joined to the counterpart in a pressure-tight manner forming a pressure chamber between the measurement membrane and the counterpart by means of an active brazing solder. The pressure measurement cell furthermore has a solder stop layer on a surface of the measurement membrane and/or the counterpart, wherein the solder stop layer has a metal oxide or a reduced form of the metal oxide. The metal oxide has at least one oxidation stage, which, assuming an activity coefficient of R.sub.akt=1 at an inverse temperature of 8.Math.10.sup.4/K, has an oxygen coexistence decomposition pressure of not less than 1.sup.23 MPa (10.sup.23.Math. bar) and not more than 1.sup.12 MPa (10.sup.12.Math. bar) and which, assuming an activity coefficient of R.sub.akt=1, at an inverse temperature of 9.Math.10.sup.4/K has an oxygen coexistence decomposition pressure of not less than 1.sup.27 MPa (10.sup.27 bar) and not more than 1.sup.15 MPa (10.sup.15 bar). Suitable metal oxides are, for example, oxides of chromium, tungsten or titanium.

A milling device is rotatable in one direction around a longitudinal center axis defining a forward direction and an opposite rearward direction, and includes a front part and a rear part. The front part has cutting edges, each having a longitudinal extension, and chip flutes, each having a longitudinal extension. The front part is made of a monolithic piece of ceramic. The rear part is configured to be fixed in a rotatable tool body or a rotatable chuck. The rear part is also made of a monolithic piece of cemented carbide. A front end surface of the rear part has a smaller area than a rear end surface of the front part. The front end surface of the rear part and a rear end surface of the front part are permanently bonded or brazed to each other by a joint.

The present invention provides a high thermal conductive silicon nitride sintered body having a thermal conductivity of 50 W/m.Math.K or more and a three-point bending strength of 600 MPa or more, wherein when an arbitrary cross section of the silicon nitride sintered body is subjected to XRD analysis and highest peak intensities detected at diffraction angles of 29.30.2, 29.70.2, 27.00.2, and 36.10.2 are expressed as I.sub.29.3, I.sub.29.7, I.sub.27.0, and I.sub.36.1, a peak ratio (I.sub.29.3)/(I.sub.27.0+I.sub.36.1) satisfies a range of 0.01 to 0.08, and a peak ratio (I.sub.29.7)/(I.sub.27.0+I.sub.36.1) satisfies a range of 0.02 to 0.16. Due to above configuration, there can be provided a silicon nitride sintered body having a high thermal conductivity of 50 W/m.Math.K or more, and excellence in insulating properties and strength.

This A copper/ceramic bonded body includes: a copper member made of copper or a copper alloy; and a ceramic member made of oxygen-containing ceramics, wherein the copper member and the ceramic member are bonded to each other, a magnesium oxide layer is formed on a ceramic member side between the copper member and the ceramic member, and an active metal oxide phase composed of an oxide of one or more active metals selected from Ti, Zr, Nb, and Hf is dispersed inside a copper layer in contact with the magnesium oxide layer.