Silicon carbide diffusion furnace components

In a semi-conductor diffusion furnace, a process tube consisting essentially of a sintered silicon carbide matrix rendered impervious by impregnation of at least the inner surface of said process tube with silicon metal, said silicon metal being present in the range of 5 to 30% by weight and having purity of not less than 99% silicon.

In a semi-conductor diffusion furnace, a paddle consisting essentially of a sintered silicon carbide matrix rendered impervious by at least partial impregnation of all surfaces thereof with silicon metal, said silicon metal being present in the range of 5 to 30% by weight and having a purity of at least 99% silicon.

In a semi-conductor diffusion furnace, a boat consisting essentially of a sintered silicon carbide matrix rendered impervious by at least partial impregnation of all surfaces thereof with silicon metal, said silicon metal being present in the range of 5 to 30% by weight and having a purity of at least 99% silicon.

In a semi-conductor diffusion furnace a gas impervious process tube, boat and paddle, said process tube, boat, and paddle consisting essentially of from 70 to 95% by weight of a sintered recrystallized silicon carbide matrix which is 99 to 100% pure silicon carbide, impregnated with 5 to 30% by weight of silicon metal which is at least 99.9% pure silicon, the composite of silicon carbide and silicon having a modulus of rupture at room temperature of at least 10,000 p.s.i. (700 kg./cm..sup.2).

A system for a semi-conductor diffusion furnace comprising a process tube, a mating paddle, and at least one boat supportable on said paddle, wherein said process tube, paddle and boat consist essentially of a sintered silicon carbide matrix impregnated with 5 to 30% by weight of silicon metal which is at least 99.9% pure, said silicon metal impregnant rendering said process tube, paddle, and boat gas impervious, and wherein said process tube has a cone shaped end terminating in a ball joint suitable for attachment to an apparatus for introduction of gas into said process tube.