A first ceramic member and a second ceramic member are joined together at a lower joining temperature while reducing the loss of bond strength. A method for producing a semiconductor production device component includes a step of providing a first ceramic member including an AlN-based material, a step of providing a second ceramic member including an AlN-based material, and a step of joining the first ceramic member and the second ceramic member to each other by thermally pressing the first ceramic member and the second ceramic member to each other via a joint agent including Eu.sub.2O.sub.3, Gd.sub.2O.sub.3 and Al.sub.2O.sub.3 disposed between the first ceramic member and the second ceramic member.

The bonded ceramic assembly of the present disclosure includes a first substrate made of ceramic, a second substrate made of ceramic, and a bonding layer positioned between the first substrate and the second substrate. The bonding layer contains aluminum, at least one of calcium and magnesium, a rare earth element, silicon, and oxygen. Out of a total 100 mass % of all of the components making up the bonding layer, the bonding layer contains from 33 mass % to 65 mass % aluminum in terms of oxide, a total of from 27 mass % to 60 mass % calcium and magnesium in terms of oxide, and from 2 mass % to 12 mass % rare earth element in terms of oxide. The silicon content, in terms of oxide, of the surface of the bonding layer is greater than the silicon content, in terms of oxide, of the interior of the bonding layer.

Disclosed is a joined ceramic body comprising a first ceramic portion comprising a first ceramic, a second ceramic portion comprising a second ceramic, and a joining layer formed between the first ceramic portion and the second ceramic portion. The joining layer has a bond thickness of from 0.5 to 20 um and comprises silicon dioxide having a total impurity content of 20 ppm and less. A method of making the joined ceramic body and a joining material are also disclosed.

Provided is a polycrystalline ceramic substrate to be bonded to a compound semiconductor substrate with a bonding layer interposed therebetween, wherein at least one of relational expression (1) 0.7<α.sub.1/α.sub.2<0.9 and relational expression (2) 0.7<α.sub.3/α.sub.4<0.9 holds, where α.sub.1 represents a linear expansion coefficient of the polycrystalline ceramic substrate at 30° C. to 300° C. and α.sub.2 represents a linear expansion coefficient of the compound semiconductor substrate at 30° C. to 300° C., and α.sub.3 represents a linear expansion coefficient of the polycrystalline ceramic substrate at 30° C. to 1000° C. and α.sub.4 represents a linear expansion coefficient of the compound semiconductor substrate at 30° C. to 1000° C.

A pillar shaped honeycomb structure for induction heating, the honeycomb structure being made of ceramics and including: an outer peripheral wall; and a partition wall disposed on an inner side of the outer peripheral wall, the partition wall defining a plurality of cells, each of the cells penetrating from one end face to other end face to form a flow path, wherein a composite material containing a conductor and a non-conductor is provided in the cells in a region of 50% or less of the total length of the honeycomb structure from one end face, and wherein the conductor is a conductor that generates heat in response to a change in a magnetic field.

Methods of forming a ceramic matrix, as well as fiber preforms and methods of forming fiber preforms to facilitate formation of a ceramic matrix are provided. The method includes obtaining a fiber preform to facilitate forming the ceramic matrix. The fiber preform includes a fiber layer with a plurality of fibers and a heating element embedded within the fiber preform. The method also includes heating the fiber preform via the heating element embedded within the fiber preform, and depositing matrix material into the fiber preform by embedded wire chemical vapor deposition (EWCVD) of the matrix material during the heating of the fiber preform by the heating element. The chemical vapor deposition of the matrix material within the fiber preform facilitates formation of the ceramic matrix.

The present invention discloses a polyimide-based composite carbon film with high thermal conductivity and a preparation method therefor. The preparation method includes: uniformly coating the surface of a polyimide-based carbon film with an aqueous graphene oxide solution, and then covering the same with another polyimide-based carbon film uniformly coated with an aqueous graphene oxide solution; repeating such operation; after the polyimide-based carbon films are dried, bonding the polyimide-based carbon films by means of graphene oxide so as to form a thick film; bonding the polyimide-based carbon films more tightly by means of further low-temperature hot pressing; and finally, obtaining a thick polyimide-based carbon film with high thermal conductivity by repairing defects by means of low-temperature heating pre-reduction and high-temperature and high-pressure thermal treatment. The thick polyimide-based carbon film with high thermal conductivity has a thickness greater than 100 μm and an in-plane thermal conductivity of even reaching 1700 W/mK or above.

A method for manufacturing a sensor element that includes: a pair of electrodes; a ceramic layer having a hollow space that is to be an air introduction hole; and a first layer and a second layer stacked at both surfaces of the ceramic layer, One of the electrodes is in communication with the hollow space, The method includes: preparing an unsintered ceramic sheet, and a burn-out material sheet having a thickness different from that of the unsintered ceramic sheet, the burn-out material sheet having, in a plane orthogonal to the direction of an axial line O, a cross-sectional area substantially identical to a cross-sectional area of the pre-sintering hollow space; placing the burn-out material sheet in the pre-sintering hollow space; pressing the sheets so as to have an identical thickness; and burning out the burn-out material sheet.

A ceramic joined body (1) includes: a pair of ceramic plates (2,3) that include a conductive material; and a conductive layer (4) and an insulating layer (5) that are interposed between the pair of ceramic plates (2, 3), a porosity at an interface between the pair of ceramic plates (2, 3) and the insulating layer (5) is 4% or less, and a ratio of an average primary particle diameter of an insulating material which forms the insulating layer (5) to an average primary particle diameter of an insulating material which forms the ceramic plates (2, 3) is more than 1.

A YAG ceramic bonded body in which a YAG ceramic and a YAG ceramic or optical glass are bonded, wherein the YAG ceramic bonded body comprises glass as a bonding layer, and has a rate of change of transmittance that is within 7%. An object of this invention is to provide a bonded body in which a YAG ceramic and a YAG ceramic are bonded, or a bonded body in which a YAG ceramic and optical glass are bonded, and which is capable of suppressing the reflection of light at the bonded interface, as well as the production method thereof.