Abstract: A reagent assembly for a combustion tube includes a reagent tube which is sealably and removably coupled to the open end of the combustion tube such that, when the reagent in the reagent tube is depleted, it can be easily removed without disassembly of the furnace or changing the combustion tube. The reagent tube includes a twist-lock cap to facilitate removal of the reagent tube.

Abstract: A method for forming a cavity (30) to a structure such as a poly fuse (114) with a deep etch process whereby a mask is formed over the structure a first dielectric layer (23) and an etch partially through the first dielectric layer is performed. Next, a second dielectric layer (34) is deposited and a second mask is formed for completing the etch to the structure. Finally, an etch through the second dielectric (34) to an area at or near the structure is performed. A resultant device has non-etched second dielectric material on the sidewalls of the etch cavity 30.

Abstract: A method for forming a cavity (30) to a structure such as a poly fuse (114) with a deep etch process whereby a mask is formed over the structure a first dielectric layer (23) and an etch partially through the first dielectric layer is performed. Next, a second dielectric layer (34) is deposited and a second mask is formed for completing the etch to the structure. Finally, an etch through the second dielectric (34) to an area at or near the structure is performed. A resultant device has non-etched second dielectric material on the sidewalls of the etch cavity 30.