Disclosed is to provide a composite structure used as a member for a semiconductor manufacturing apparatus with which low-particle generation can be improved, as well as a semiconductor manufacturing apparatus including the same. A composite structure including a base material and a structure that is provided on the base material and has a surface, in which the structure comprises Y.sub.3Al.sub.5O.sub.12 as a main component, and has an indentation hardness being larger than 8.5 GPa features excellent low-particle generation and is suitably used as a member for a semiconductor apparatus.

Disclosed is to provide a composite structure used as a member for a semiconductor manufacturing apparatus with which low-particle generation can be improved, as well as a semiconductor manufacturing apparatus including the same. A composite structure including a base material and a structure that is provided on the base material and has a surface, in which the structure comprises Y.sub.3Al.sub.5O.sub.12 as a main component, and has an indentation hardness being larger than 8.5 GPa features excellent low-particle generation and is suitably used as a member for a semiconductor apparatus.

A porous ceramic structure includes a porous honeycomb structure composed primarily of cordierite, and Ce- and Zr-containing particles fixedly attached to the honeycomb structure. The Ce- and Zr-containing particles contain Ce and Zr. The Ce- and Zr-containing particles have a fixedly attached portion located inside the honeycomb structure and a protrusion contiguous with the fixedly attached portion and protruding from the honeycomb structure.

A porous ceramic structure includes a porous honeycomb structure composed primarily of cordierite, and Ce- and Zr-containing particles fixedly attached to the honeycomb structure. The Ce- and Zr-containing particles contain Ce and Zr. The Ce- and Zr-containing particles have a fixedly attached portion located inside the honeycomb structure and a protrusion contiguous with the fixedly attached portion and protruding from the honeycomb structure.

A process for manufacturing an abradable layer, includes compressing a powder composition including at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], and sintering the powder composition thus compressed to obtain the abradable layer, wherein a temperature imposed during sintering, the sintering time and the compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.

A process for manufacturing an abradable layer, includes compressing a powder composition including at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], and sintering the powder composition thus compressed to obtain the abradable layer, wherein a temperature imposed during sintering, the sintering time and the compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.

A method for manufacturing a pillar-shaped honeycomb structure filter including a step of preparing a pillar-shaped honeycomb structure having a plurality of first cells and a plurality of second cells that are alternately arranged adjacent to each other with a porous partition wall interposed therebetween; a step of adhering ceramic particles containing 50% by mass or more in total of one or two selected from SiC and SiN to a surface of the first cells; and a step of performing a heat-oxidation treatment on the pillar-shaped honeycomb structure in which the ceramic particles are adhered to the surface of the first cells to form a porous film comprised of the ceramic particles having an oxide film thereon so as to satisfy: (1) 0.05≤T≤0.5; (2) 0.05≤T/D50; and (3) 4≤{(W.sub.1−W.sub.0)/W.sub.0×100}/D50.

A method for manufacturing a pillar-shaped honeycomb structure filter including a step of preparing a pillar-shaped honeycomb structure having a plurality of first cells and a plurality of second cells that are alternately arranged adjacent to each other with a porous partition wall interposed therebetween; a step of adhering ceramic particles containing 50% by mass or more in total of one or two selected from SiC and SiN to a surface of the first cells; and a step of performing a heat-oxidation treatment on the pillar-shaped honeycomb structure in which the ceramic particles are adhered to the surface of the first cells to form a porous film comprised of the ceramic particles having an oxide film thereon so as to satisfy: (1) 0.05≤T≤0.5; (2) 0.05≤T/D50; and (3) 4≤{(W.sub.1−W.sub.0)/W.sub.0×100}/D50.

In some examples, a braze material includes a first set of particles, a second set of particles, and a polymeric binder. The first set of particles includes a braze powder, where the braze powder comprises an Si-containing alloy. The first set of particles defines an average or median particle diameter between about 1 μm and about 40 μm. The second set of particles includes at least one of SiC or a transition metal carbide, where the second set of particles has a multimodal particle size distribution.

In some examples, a braze material includes a first set of particles, a second set of particles, and a polymeric binder. The first set of particles includes a braze powder, where the braze powder comprises an Si-containing alloy. The first set of particles defines an average or median particle diameter between about 1 μm and about 40 μm. The second set of particles includes at least one of SiC or a transition metal carbide, where the second set of particles has a multimodal particle size distribution.