Patent ID: 8821607

Claim:
A particle capture unit in a substrate processing apparatus, the particle capture unit comprising: a sheet-shaped particle capturing multilayer structure including a first layer formed of a plurality of first fibers and a second layer formed of a multiplicity of second fibers, wherein the first fibers are thinner than the second fibers and an arrangement density of the first fibers in the first layer is higher than that of the second fibers in the second layer, wherein the substrate processing apparatus includes an exhaust system communicating with a pump having rotational blades, and wherein the exhaust system includes a gas-impermeable member having an inner peripheral surface, and further wherein a space is defined within the inner peripheral surface through which a particle-containing exhaust gas flows; wherein the multilayer structure is configured to be disposed along the inner peripheral surface of the gas-impermeable member such that the second layer is interposed between the first layer and the space, and wherein the first layer and the second layer are hardened and bonded together by sintering.