Reticle pod having coated sensor zones
Sensor zones are created on an inner pod of a reticle container using a dry coating method. The sensor zones are discrete zones having a specific spectral reflectivity. The sensor zones are positioned such that they can be read by a tool to determine distance of portions of the pod. The use of discrete zones and a dry coating method for applying those discrete zones overcomes issues with inconsistency and difficulty in cleaning or maintaining reflectance of an inner pod of the reticle container in comparison with inner pods plated entirely with material or other wet coating applied materials.
1 . A pod, comprising:
a baseplate having a baseplate surface, the baseplate surface being outward-facing and including a baseplate surface material;
a cover having a cover surface, the cover surface being an outward-facing and including a cover surface material; and
one or more discrete sensor zones, each of the sensor zones including a reflective material, the one or more discrete sensor zones disposed on one or both of the baseplate surface and the cover surface,
wherein when joined, the cover and the baseplate are configured to define an internal space to accommodate a reticle,
wherein the discrete sensor zones cover less than the entirety of the baseplate surface and/or the cover surface, and
wherein each of the one or more discrete sensor zones is formed by a dry coating process.
2 . The pod of claim 1 , wherein the pod is a EUV reticle pod.
3 . The pod of claim 2 , further comprising an outer pod dome and an outer pod door, the pod dome and the pod door configured to accommodate the baseplate and the cover within the pod dome when the door is attached to the pod dome.
4 . The pod of claim 1 , wherein the reflective material has a spectral reflectivity at a wavelength of 880 nm of between approximately 50% and approximately 70%.
5 . The pod of claim 1 , wherein the reflective material has a reflectivity that is different from a reflectivity of the baseplate surface material.
6 . The pod of claim 1 , wherein the reflective material includes chromium.
7 . The pod of claim 6 , wherein only the reflective material includes the chromium.
8 . The pod of claim 1 , wherein the one or more discrete sensor zones disposed on the baseplate surface are positioned such that a distance between the pod and a detector can be determined from reading the one or more sensor zones.
9 . The pod of claim 1 , wherein the baseplate surface includes one of aluminum or nickel and the cover surface is one of aluminum or nickel.
10 . The pod of claim 1 , wherein each of the baseplate surface and the cover surface includes one or more of the discrete sensor zones.