The present invention relates to a granular thermal insulation material comprising hydrophobized silicon dioxide and at least one IR opacifier, having a tamped density of up to 250 g/l and a compressive strength according to DIN EN 826:2013 at 50% compression of 150 to 300 kPa or greater than 300 kPa, to processes for production thereof and to the use thereof for thermal insulation.

Disclosed herein are embodiments of low temperature co-fireable scheelite materials which can be used in combination with high dielectric materials, such as nickel zinc ferrite, to form composite structures, in particular for isolators and circulators for radiofrequency components. In some embodiments, the scheelite material can include aluminum oxide for temperature expansion regulation.

Provided is a refractory product which is not impregnated with pitch or the like, wherein it has higher corrosion-erosion resistance and thermal shock resistance as compared to a refractory product subjected to pitch or the like-impregnation treatment. The refractory product which is not impregnated with tar or pitch is characterized in that, in terms of values of physical properties of a sample of the refractory product as measured after heat-treating the sample in a non-oxidizing atmosphere at 1200° C.: an apparent porosity is 7% or less; a total void volume of pores having a pore diameter of 1 μm or less is 80% or more of an integrated void volume of pores of the entire sample of the refractory product; and a gas permeability is 50×10.sup.−17 m.sup.2 or less.

A sintered body includes a crystal grain containing silicon nitride, and a grain boundary phase. If dielectric losses of the sintered body are measured while applying an alternating voltage to the sintered body and continuously changing a frequency of the alternating voltage from 50 Hz to 1 MHz, an average value ε.sub.A of dielectric losses of the sintered body in a frequency band from 800 kHz to 1 MHz and an average value ε.sub.B of dielectric losses of the sintered body in a frequency band from 100 Hz to 200 Hz satisfy an expression |ε.sub.A−ε.sub.B|≤0.1.

A method of making a ceramic composite component includes providing a fibrous preform or a plurality of fibers, providing a first plurality of particles, coating the first plurality of particles with a coating to produce a first plurality of coated particles, delivering the first plurality of coated particles to the fibrous preform or to an outer surface of the plurality of fibers, and converting the first plurality of coated particles into refractory compounds. The first plurality of particles or the coating comprises a refractory metal.

A substrate support structure includes a substrate support structure body formed from a ceramic composite and having a first surface, a second surface spaced apart from the first surface, and a periphery spanning the first surface and the second surface of the substrate support structure body. The first surface, the second surface, and the periphery of the substrate support structure body are defined by the ceramic composite. The ceramic composite includes two or more of a (a) an aluminum nitride (AlN) constituent, (b) an aluminum oxynitride (Al.sub.2.81O.sub.3.56N.sub.0.44, AlON) constituent, (c) an alpha-alumina (α-Al.sub.2O.sub.3) constituent, (d) a yttrium alumina garnet (Y.sub.3Al.sub.5O.sub.12, YAG) constituent, (e) a yttrium alumina monoclinic (Y.sub.4Al.sub.2O.sub.9, YAM) constituent, (f) a yttrium alumina perovskite (YAlO.sub.3, YAP) constituent, and (g) a yttrium oxide (Y.sub.2O.sub.3) constituent. Semiconductor processing systems and methods of making substrate support structures are also described.

A process for the manufacture of inorganic fibres comprises: (a) selecting a composition and proportion of: (i) silica sand; (ii) lime comprising at least 0.10 wt % magnesia; and (iii) optional additives comprising a source of oxides or non-oxides of one or more of the lanthanides series of elements, or combinations thereof; (b) mixing the silica sand; lime; and optional additives to form a mixture; (c) melting the mixture in a furnace; and (d) shaping the molten mixture into inorganic fibres. The raw materials selection comprises composition selection and proportion selection of the raw materials to obtain an inorganic fibre composition comprising a range of from 61.0 wt % and 70.8 wt % silica; less than 2.0 wt % magnesia; less than 2.0% incidental impurities; and no more than 2.0 wt % of metal oxides and/or metal non-oxides derived from said optional additives; with calcia providing the balance up to 100 wt %; and wherein the inorganic fibre composition comprises no more than 0.80 wt % Al.sub.2O.sub.3 derived from the incidental impurities and/or the optional additives.

A pore-free ceramic is provided that has a high modulus of elasticity and a low coefficient of thermal expansion. A process for producing a corresponding ceramic is also provided. The pore free ceramic is a dimensionally stable substrate material in applications subjected to temperature gradients including semiconductor manufacture.

Disclosed herein are embodiments of low temperature co-fireable dielectric materials which can be used in conjunction with high dielectric materials to form composite structures, in particular for isolators and circulators for radiofrequency components. Embodiments of the low temperature co-fireable dielectric materials can be scheelite or garnet structures, for example, bismuth vanadate. Adhesives and/or glue is not necessary for the formation of the isolators and circulators.

The present invention relates to a method for preparing a SiC—Si.sub.3N.sub.4 composite material and a SiC—Si.sub.3N.sub.4 composite material prepared according to same and comprises the steps of: preparing a mold; and forming a SiC—Si.sub.3N.sub.4 composite material by introducing, to the mold, a source gas comprising Si, N and C, at 1100 to 1600° C. More particularly, the present invention provides the SiC—Si.sub.3N.sub.4 composite material of high purity that is applicable to a semiconductor process, and increases the thermal shock strength of a SiC material by causing Si.sub.3N.sub.4, which is a material with a high thermal shock strength, to grow together via a CVD method.