A dual containment pod having an outer pod and an inner pod that provides support structure and environmental control means. The inner pod includes a base having a flat, polished surface with protrusions upon which the reticle seats and providing a gap between the reticle and the polished surface. The gap separates the reticle from the flat, polished surface of the base and is dimensioned to inhibit migration of particles into the gap, thereby preventing contamination of sensitive surfaces of the wafer or reticle. The top cover of the inner pod seats on the polished surface proximate a periphery of the base. Moveable reticle engaging pins on the top cover of the inner pod are engaged by the top cover of the outer container when the inner pod is assembled inside the outer pod providing reticle restraint.
1. A container for holding reticles, the reticle having a periphery, a top surface, a bottom surface, a side surface, four peripheral corners, a top edge and a bottom edge, the container comprising:
an outer container sized to receive an inner container, the outer container comprising an outer cover and a door receivable within the outer cover to define an interior, wherein the inner container comprises
a base for receiving the reticle, the base having a periphery, and a top upwardly facing horizontal metal surface, the upwardly facing horizontal surface having a planar metal sealing surface extending around the base at or proximate to the periphery of said base, the base further having four pairs of posts and a rounded seating element positioned intermediate each pair of posts, the four pairs of posts and respective rounded seating element positioned therebetween defining a reticle seating position above the top upwardly facing horizontal metal surface; and
a cover for engaging the top surface of the base plate along the base plate periphery, thereby defining an interior for holding the reticle, the cover having a downwardly facing horizontal planar metal sealing surface for cooperating with the planar metal sealing surface of the base to create a seal therebetween when said respective surfaces are in contact.
2. The container of claim 1 wherein the top surface of the base is continuously planar and integral from the sealing surface to below the reticle.
3. The container of claim 2 wherein the downwardly facing horizontal planar sealing surface has a nickel finish.
4. The container of claim 1 wherein the base is formed primarily of metal.
5. The container of claim 1 wherein the cover comprises a plurality of vertically moveable members positioned in a plurality of apertures in the cover, the members positioned to engage the reticle.
6. The container of claim 5 wherein the each of the moveable reticle members are resiliently positioned in the cover.
7. The container of claim 1 wherein the cover comprises a plurality of vertically moveable members positioned in the cover, the vertically movable members positioned to engage the reticle and are actuatable externally with respect to the cover.
8. The container of claim 1 wherein the top surface of the base and the downwardly facing horizontal planar metal sealing surface of the cover each have a surface finish with a roughness average (RA) of up to 0.50 micro inches.
9. The container of claim 1 wherein the top surface of the base and the downwardly facing horizontal planar metal sealing surface of the cover each have a surface finish with a roughness average (RA) of between 0.20-0.40 micro inches.
10. The container of claim 1 wherein the outer cover includes a plurality of resilient members extending downwardly on an inside surface of said outer cover, and wherein said resilient members engage the top cover of the container.
11. The container of claim 1 wherein the top cover is primarily formed of a polymer and the sealing surface of the top cover is part of a metal ring secured to said polymer.