Patent ID: 7335397
Filing Date: 2008-02-26
Classification: C23C,Y10S

Abstract:
1. A process for densifying porous structures inside a furnace, the process comprising: providing a furnace, the furnace defining an outer volume; assembling a multitude of porous structures and ring-shaped spacers in a stack with a ring-shaped spacer between each adjacent pair of porous structures, wherein at least one of the ring-shaped spacers comprises a plurality of channels; disposing the stack of porous structures between a bottom plate and a top plate in the furnace, wherein the bottom plate, the stack of porous structures, and the ring-shaped spacers define an enclosed cavity extending from the bottom plate, including each porous structure aperture, and terminating proximate the top plate; providing fluid communication between the enclosed cavity and the outer volume through the plurality of channels in the at least one ring-shaped spacer; allowing a gas to flow through the channel while maintaining a pressure gradient between the enclosed cavity and the outer volume; and densifying the porous structures from an average density of less than 0.60 g/cm