Reticle pod including movement limiting features and method of assembly thereof - Patents.com

Abstract

The reticle pod includes an inner pod where a movement limiting feature restricts translational movement of the cover and base plate relative to one another. The movement limiting feature is in addition to a gross alignment feature included in the inner pod. The movement limiting feature resists movement before the gross alignment feature resists translational movement. The movement limiting feature can include an elastomer that provides friction against a contact surface, or a pin that is received on the elastomer contact surface or in a diaphragm or movement limiting cup.

Description

[Technical Field]

[0001] Priority This disclosure claims priority to U.S. Provisional Patent No. 63 / 277,188, filed November 9, 2021. The priority document is incorporated herein by reference.

[0002] The present disclosure is directed to reticle pods, and in particular to reticle pods that include fine as well as gross alignment features. [Background technology]

[0003] The reticle pod may be used to hold a reticle, for example, to secure the reticle during processing such as photolithography, including extreme ultraviolet (EUV) processes. The reticle pod may include an outer pod and an inner pod, the inner pod including a cover and a base plate. The cover and base plate may be made of a hard material, such as metal. Relative movement of the cover and base plate may cause the hard materials to rub against each other, resulting in the generation of particles due to wear as the surfaces of the cover and base plate rub against each other. Summary of the Invention

[0004] The present disclosure is directed to reticle pods, and in particular to reticle pods that include fine as well as gross alignment features.

[0005] Reticle pods according to embodiments may be used in processes such as, for example, extreme ultraviolet (EUV) processes. Movement limiting features may be provided to improve the relative positioning of the cover and base plate of the reticle pod. The movement limiting features may constrain the cover and base plate to smaller relative movements, reducing rubbing between the cover and base plate, thereby reducing particle generation during use of the reticle pod. This may improve the purity of processes performed using the reticle pod, increase yield, reduce losses due to particle contamination, misalignment of pod components, etc.

[0006] In one embodiment, the reticle pod includes an inner pod including a base plate and a cover. The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features. Each of the plurality of movement-limiting features includes an alignment-retaining cutout formed in one of the cover or the base plate and an elastic body disposed in the alignment-retaining cutout. The elastic body is configured to contact both the base plate and the cover when the inner pod is assembled. The plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force.

[0007] In one embodiment, the reticle pod includes an inner pod including a base plate and a cover. The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features. Each of the plurality of movement-limiting features includes a mating pin extending from one of the cover or the base plate and a resilient contact surface provided on the other of the cover or the base plate. The mating pin is configured to contact the resilient contact surface when the inner pod is assembled. The plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force.

[0008] In one embodiment, the resilient contact surface is provided on a resilient body, the resilient body including a hollow portion opposite a surface where the mating pin is configured to contact said resilient contact surface.

[0009] In one embodiment, each of the mating pins is disposed in a mating pin channel, each mating pin channel being formed in one of the cover or the base plate.

[0010] In one embodiment, the reticle pod includes an inner pod including a base plate and a cover. The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features. Each of the plurality of movement-limiting features includes a diaphragm disposed in one of the cover or the base plate and a pin extending from the other of the cover or the base plate, the pin configured to contact the diaphragm when the inner pod is assembled. The diaphragm has a resistance to deformation in a direction coplanar with the cover or base plate that is greater than the resistance to deformation in a direction perpendicular to the plane of the cover or base plate. Each of the pins has a taper at an end configured to contact one of the plurality of diaphragms. The plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force.

[0011] In one embodiment, each of the travel-limiting features includes an alignment-retaining cutout configured to receive a diaphragm and a retaining ring configured to retain the diaphragm in the alignment-retaining cutout.

[0012] In one embodiment, the pin is disposed in a pin channel formed in one of the cover or the base plate.

[0013] In one embodiment, the reticle pod includes an inner pod including a base plate and a cover. The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features. Each of the plurality of movement-limiting features includes a movement-limiting pin extending from one of the cover or the base plate and a movement-limiting cup disposed in the other of the cover or the base plate. The movement-limiting pin is configured to be contacted by a plurality of different surfaces of the movement-limiting cup when the inner pod is assembled. The plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force.

[0014] In one embodiment, the movement limiting cup is formed directly into one of the cover or base plate.

[0015] In one embodiment, the travel limiting cup is formed in an insert, the insert being configured to be received in a recess formed in one of the cover or base plate.

[0016] In one embodiment, a method for securing an inner pod of a reticle pod includes engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate, and engaging each of a plurality of movement-limiting features provided on one of the cover or the base plate with the other of the cover or the base plate. The plurality of movement-limiting features includes a plurality of alignment-retaining cutouts and a plurality of elastomers. Each elastomer is disposed in one of the alignment-retaining cutouts, and each of the plurality of elastomers is configured to contact both the base plate and the cover when the inner pod is assembled. When a force having a component flush with the cover or the base plate acts on the inner pod, engagement of the movement-limiting features provides resistance to a component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. In one embodiment, the reticle is placed within an inner pod, and the method further includes placing the inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod, and subjecting the inner pod to an extreme ultraviolet process.

[0017] In one embodiment, a method for securing an inner pod of a reticle pod includes engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate, and engaging each of a plurality of movement-limiting features provided on one of the cover or the base plate with the other of the cover or the base plate. The plurality of movement-limiting features includes a plurality of mating pins extending from one of the cover or the base plate and a plurality of resilient contact surfaces on the other of the cover or the base plate. Each of the plurality of mating pins is configured to contact one of the resilient contact surfaces. When a force having a component coplanar with the cover or the base plate acts on the inner pod, engagement of the movement-limiting features provides resistance to a component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. In one embodiment, the reticle is placed within an inner pod, and the method further includes placing the inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod, and subjecting the inner pod to an extreme ultraviolet process.

[0018] In one embodiment, a method for securing an inner pod of a reticle pod includes engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate, and engaging each of a plurality of movement-limiting features provided on one of the cover or the base plate with the other of the cover or the base plate. The plurality of movement-limiting features include a plurality of diaphragms, each of the plurality of diaphragms disposed in one of the cover or the base plate, and a plurality of pins extending from the other of the cover or the base plate. Each of the plurality of pins is configured to contact one of the plurality of diaphragms when the inner pod is assembled. Each of the plurality of diaphragms has a resistance to deformation in a direction coplanar with the cover or the base plate that is greater than its resistance to deformation in a direction perpendicular to the plane of the cover or the base plate. Each of the pins has a taper at an end configured to contact one of the plurality of diaphragms. When a force having a component flush with the cover or base plate acts on the inner pod, engagement of the travel-limiting feature provides resistance to the component of the force before engagement of the cover gloss alignment feature with the base plate gloss alignment feature provides resistance to the component of the force. In one embodiment, a reticle is disposed within the inner pod, and the method further includes placing the inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod, and subjecting the inner pod to an extreme ultraviolet process.

[0019] In one embodiment, a method for securing an inner pod of a reticle pod includes engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate, and engaging each of a plurality of movement-limiting features provided on one of the cover or the base plate with the other of the cover or the base plate. The plurality of movement-limiting features includes a plurality of movement-limiting pins extending from one of the cover or the base plate and a plurality of movement-limiting cups provided in the other of the cover or the base plate. Each of the plurality of movement-limiting pins is configured to be contacted by a plurality of different surfaces of one of the plurality of movement-limiting cups when the inner pod is assembled. When a force having a component coplanar with the cover or the base plate acts on the inner pod, engagement of the movement-limiting feature provides resistance to the component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. In one embodiment, the reticle is placed within an inner pod, and the method further includes placing the inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod, and subjecting the inner pod to an extreme ultraviolet process.

[0020] In one embodiment, the reticle pod includes an inner pod including a base plate and a cover. The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features. Each of the plurality of movement-limiting features includes: a pin extending from the cover on a side of the cover configured to face the base plate when the inner pod is assembled; a slot formed in the base plate configured to receive the pin; and a flexible member configured to cover the slot on a side of the base plate opposite the cover when the inner pod is assembled. The flexible member includes a contact surface configured to be contacted by an end of the pin, and the flexible member is configured such that the contact surface can be deflected by contact with the pin.

[0021] In one embodiment, the inner pod includes at least three of the movement-limiting features. In one embodiment, the major axis of each slot extends in a different direction than the major axes of all other slots.

[0022] In one embodiment, the reticle pod further includes a base plate retention feature formed in the base plate, and the flexible member includes a flexible member retention feature configured to engage the base plate retention feature. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 illustrates a reticle pod, according to one embodiment. [Figure 2] FIG. 10 illustrates a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. [Figure 3] FIG. 10 illustrates a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. [Figure 4] FIG. 10 illustrates a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. [Figure 5] FIG. 10 illustrates a top view of a diaphragm in a base plate of a reticle pod, according to one embodiment. [Figure 6] FIG. 10 illustrates a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. [Figure 7] FIG. 10 illustrates a base plate of an inner pod of a reticle pod, according to one embodiment. [Figure 8] FIG. 10 illustrates a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present disclosure is directed to reticle pods, and in particular to reticle pods that include fine as well as gross alignment features.

[0025] 1 illustrates a reticle pod, according to one embodiment. Reticle pod 100 is configured to house a reticle 102. Reticle pod 100 includes an outer pod 104, which includes a pod dome 106 and a pod door 108. Reticle pod 100 further includes an inner pod 110, which includes a base plate 112 and a cover 114. Inner pod 110 further includes a gross alignment feature 116.

[0026] Reticle pod 100 is particularly configured to store reticles during transport, handling, and processing, such as for processing by photolithography, including extreme ultraviolet (EUV). Reticles are, for example, photolithography masks for semiconductor wafers. Reticle 102 is, for example, a reticle that can be contained within reticle pod 100 for transport, handling, or processing, such as for processing by photolithography, including EUV.

[0027] The reticle pod 100 includes an outer pod 104. The outer pod 104 is configured to house the inner pod 110. The outer pod 104 may include a pod dome 106 and a pod door 108. The outer pod 104 may be made, for example, from a polymer material. The pod dome 106 and the pod door 108 may be configured such that the pod dome 106 and the pod door 108 can be secured to one another to define an enclosed space, for example, via a latching mechanism (not shown).

[0028] The inner pod 110 is configured to house the reticle 102. The inner pod 110 may be sized so that the inner pod 110 can be placed within the outer pod 104. The inner pod 110 may include a metallic material, such as being made of metal, being made of metal with a coating, including one or more metal components, etc. The inner pod 110 includes a base plate 112 and a cover 114. The base plate 112 and the cover 114 are configured to be placed together to seal the reticle 102 within the inner pod 110. The base plate 112 and the cover 114 may include alignment features for the base plate 112 and the cover 114, as described below and shown in FIGS. 2-6. The alignment features may be configured to reduce relative movement of the base plate 112 and the cover 114 relative to one another to reduce rubbing at their contact surfaces. The alignment features may be added to the gross alignment feature 116 that is used to guide assembly of the inner pod 110. In one embodiment, the alignment features may be provided on the gross alignment feature 116, such as providing a shoulder, ledge, or other such feature on at least a portion of the gross alignment feature 116.

[0029] The gross alignment feature 116 may be provided on one or both of the base plate 112 and the cover 114 to facilitate proper assembly of the inner pod 110. The gross alignment feature may be any feature suitable for guiding or regulating the relative alignment of the base plate 112 and the cover 114 when the inner pod 110 is assembled. In the embodiment shown in FIG. 1 , the gross alignment feature 116 is an extension of the cover 114 at a portion of the outer periphery of the cover 114 that protrudes outward with respect to the surface of the cover 114 that faces the base plate 112 when the inner pod 110 is assembled. In the embodiment shown in FIG. 1 , the gross alignment feature 116 defines an area into which the base plate 112 is received when the inner pod 110 is assembled. In one embodiment, the gross alignment feature 116 may be provided at a corner of the base plate 112 or the cover 114. In one embodiment, the gross alignment features 116 may be provided on portions of the periphery of the base plate 112 or cover 114 other than at corners of the base plate 112 or cover 114. In one embodiment, the gross alignment features 116 may include first and second gross alignment features that engage with each other when the inner pod 110 is assembled. Other gross alignment features 116 that may be used include, by way of non-limiting example, a pin and corresponding channel as shown in FIG. 6 and described below.

[0030] 2 shows a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. The inner pod 200 includes a cover 202. The cover 202 includes a contact surface 204. The reticle pod 200 further includes a base plate 206. The base plate 206 includes an alignment-retaining cutout 208. An elastic body 210 can be disposed in the alignment-retaining cutout 208.

[0031] Inner pod 200 is an inner pod of a reticle pod, such as the inner pod of reticle pod 100 shown in FIG. 1 and described above. Inner pod 200 may be sized to fit within an outer pod of a reticle pod. Inner pod 200 may be further configured to define an interior space capable of containing a reticle, such as reticle 102 described above and shown in FIG. 1.

[0032] Cover 202 is a cover for a reticle pod, such as cover 114 of reticle pod 100 described above and shown in FIG. 1 . Cover 202 includes a contact surface 204 configured to contact at least a portion of base plate 206 and / or elastomer 210 when cover 202 and base plate 206 are assembled to form inner pod 200. In one embodiment, contact surface 204 is bare material of cover 202. In one embodiment, contact surface 204 can include a coating on the material of cover 202. In one embodiment, contact surface 204 is a flat surface of cover 202. In one embodiment, contact surface 204 is a substantially smooth surface. In one embodiment, contact surface 204 can include texturing, non-limiting examples of which include grooves, roughened sections, relatively raised bumps, combinations thereof, etc.

[0033] The base plate 206 is the base plate of the inner pod 200. The base plate 206 is configured to be joined with the cover 202 to form the inner pod 200, which provides an interior space capable of containing a reticle, such as the reticle 102 described above and shown in FIG. 1 . The base plate 206 includes a plurality of alignment-retaining cutouts 208. While one exemplary alignment-retaining cutout 208 is shown in FIG. 2 , the base plate 206 can have a plurality of such retention cutouts 208. In one embodiment, the base plate 206 includes at least three alignment-retaining cutouts 208. In one embodiment, the base plate 206 includes four alignment-retaining cutouts 208. In one embodiment, the alignment-retaining cutouts can be distributed around the periphery of the base plate 206. In one embodiment, the alignment-retaining cutouts can be positioned proximate corners of the base plate 206. The alignment-retaining cutouts 208 are each openings formed in a surface of the base plate 206 that faces the cover 202 when the inner pod 200 is assembled. The alignment-retaining cutouts 208 can each have any shape suitable for accommodating the elastic body 210 such that the elastic body 210 can be retained in the alignment-retaining cutout 208 and a portion of the elastic body 210 protrudes from the surface of the base plate 206. In one embodiment, all of the alignment-retaining cutouts 208 on the base plate 206 have the same shape. In one embodiment, at least some of the alignment-retaining cutouts 208 on the base plate 206 can have different shapes from one another.

[0034] The elastic body 210 is an object made of an elastic material and configured to be placed in one of the alignment-retaining cutouts 208 such that a portion of the elastic body 210 extends above the surface of the base plate 206 so that a portion of the elastic body 210 can contact the cover 202 at the contact surface 204 when the inner pod is assembled. The elastic body 210 can have any suitable shape based on the shape of the alignment-retaining cutout 208. In one embodiment, the elastic body 210 can be spherical in shape. In an embodiment, the elastic bodies 210 used in the inner pod 200 can each have the same shape. In an embodiment, elastic bodies 210 having different shapes can be used in a single inner pod 200. The elastic body 210 can include any suitable elastic or compressible material. The elastic or compressible material can be a material capable of withstanding conditions during processing of reticles contained within the inner pod 200. The elastic or compressible material can be an elastomer, such as a fluoroelastomer, as a non-limiting example.

[0035] While Figure 2 shows the contact surface 204 provided on the cover 202 and the alignment retaining cutout 208 provided on the base plate 206, it should be understood that the contact surface and alignment retaining cutout may be reversed so that the contact surface 204 is included in the base plate 206 and the alignment retaining cutout 208 is provided in the cover 202, with the elastic body 210 placed in the alignment retaining cutout 208 and extending outward from the surface of the cover 202 facing the base plate 206 when the inner pod 200 is assembled.

[0036] When the inner pod 200 is assembled, the contact surface 204 contacts and compresses the elastomer 210. Friction between the contact surface 204 and the elastomer 210 can provide a force that resists relative movement of the cover 202 and base plate 206 relative to one another, where the relative movement includes a component flush with the cover 202 or base plate 206. This can reduce rubbing between the cover 202 and base plate 206 and corresponding particle generation.

[0037] Contact surface 204, alignment retention cutout 208, and resilient body 210 can form travel-limiting features that retain cover 202 and base plate 206. The travel-limiting features can be separate and different from first and second gross alignment features also included in inner pod 200, such as the first and second gross alignment features shown in FIG. 6 and discussed below, such as a gross alignment pin on one of cover 202 or base plate 206 and a corresponding gross alignment channel on the other of cover 202 or base plate 206, where the gross alignment channel receives the gross alignment pin.

[0038] FIG. 3 shows a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. The inner pod 300 includes a cover 302. The cover 302 includes a mating pin 304. In the embodiment shown in FIG. 3, the mating pin 304 is disposed in a mating pin channel 306. The inner pod 300 further includes a base plate 308. The base plate 308 includes a resilient contact surface 310. In the embodiment shown in FIG. 3, the resilient contact surface 310 is included in a resilient body 312. The resilient body 312 may be disposed in an alignment retention cutout 314 formed in the base plate 308.

[0039] Inner pod 300 is an inner pod of a reticle pod, such as the inner pod of reticle pod 100 shown in FIG. 1 and described above. Inner pod 300 may be sized to fit within an outer pod of a reticle pod. Inner pod 300 may be further configured to define an interior space capable of containing a reticle, such as reticle 102 described above and shown in FIG. 1.

[0040] Cover 302 is a cover for a reticle pod, such as cover 114 of reticle pod 100 described above and shown in FIG. 1 . Cover 302 includes a plurality of mating pins 304. Each mating pin 304 is a pin extending from cover 302 on a side of cover 302 that faces base plate 308 when inner pod 300 is assembled. Each of mating pins 304 is configured to contact a resilient contact surface 310 provided on base plate 308. In one embodiment, mating pins 304 are integrally formed with cover 302. In one embodiment, mating pins 304 are separate components from cover 302 that are disposed in mating pin channels 306 formed in cover 302. In one embodiment, some or all of mating pins 304 are mating pins formed separately from cover 302 and inserted into mating pin channels 306. In one embodiment, the mating pins 304 disposed in the mating pin channels 306 may be secured by a mechanical connection between the mating pins 304 and the mating pin channels 306. In one embodiment, the mechanical connection may be a press fit. In one embodiment, the mating pin channels 306 are through-holes that extend through the entire thickness of the cover 302. In one embodiment, the mating pin channels are formed at a predetermined depth from the surface of the cover 302 that faces the base plate 308 when the inner pod 300 is assembled.

[0041] The base plate 308 is the base plate of the reticle pod. The base plate 308 is configured such that a resilient contact surface 310 can be provided to contact each of the mating pins 304 of the cover 302 when the inner pod 300 is assembled. The resilient contact surface 310 can be a surface provided on the base plate 308 made of a resilient material that faces the cover 302 when the inner pod 300 is assembled, and thus the resilient contact surface 310 is contacted by the mating pins 304 provided on the cover 302. The resilient contact surface 310 can be a surface that is raised above, flush with, or depressed relative to the surface of the base plate 308 that faces the cover 302 when the inner pod 300 is assembled. In one embodiment, at least three resilient contact surfaces 310 can be provided on the base plate 308. In one embodiment, four resilient contact surfaces 310 can be provided on the base plate 308. In one embodiment, the resilient contact surfaces 310 may be provided adjacent to corners of the base plate 308 .

[0042] The resilient contact surface 310 may be provided using an elastomer 312 disposed in an alignment-retaining cutout 314 formed in the base plate 308. The elastomer 312 may be an object having any suitable shape that includes the resilient contact surface and is configured to be retained in the alignment-retaining cutout 314. The alignment-retaining cutout 314 may have any shape suitable for receiving at least a portion of the elastomer 312. The elastomer 312 may be made from any suitable elastic or compressible material, such as, by way of non-limiting example, an elastomer such as a fluoroelastomer. The elastomer 312 is an object made from a resilient material. In one embodiment, the elastomer 312 is a plug that is insertable into the alignment-retaining cutout 314. In one embodiment, the elastomer 312 includes a lip having a circumference that is larger than the circumference of the alignment-retaining cutout 314. In one embodiment, the elastic body 312 includes an insert portion having a shape that corresponds to the alignment retention cutout 314, so that a press fit can be formed between the elastic body 312 and the base plate 308. In one embodiment, the elastic body is solid. In one embodiment, the elastic body 312 includes a hollow section opposite the portion of the elastic body 312 that is contacted by the mating pin 304.

[0043] When the inner pod 300 is assembled, the mating pins 304 each contact a corresponding one of the resilient contact surfaces 310. The mating pins 304 press into the resilient contact surfaces 310, and this contact restricts relative movement of the cover 302 and base plate 308, which have components flush with the cover 302 or base plate 308. The mating pins 304 and resilient contact surfaces 310 can form movement-limiting features in addition to or distinct from gross alignment features included in the cover 302 and / or base plate 308, such as movement-limiting pins and channels. The movement-limiting features can restrict lateral or translational movement of the base plate 308 and cover 302 relative to one another. Examples of such gross alignment features are discussed below and shown in FIG. 6, for example. When the inner pod 300 is assembled, the cover 302 and base plate 308 can contact one another. In embodiments, variations in surfaces, such as manufacturing tolerances, may cause some areas of the cover 302 and base plate 308 to not contact each other in corresponding regions.

[0044] While the embodiment shown in FIG. 3 provides the resilient contact surface 310 on the base plate 308 and the mating pin 304 on the cover 302, it should be understood that these features may be reversed such that the mating pin 304 is provided on the base plate 308 and the resilient contact surface is provided on the cover 302, with corresponding changes in the location of the mating pin channel 306, the resilient body 312, and the alignment retaining cutout 314.

[0045] FIG. 4 shows a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. The inner pod 400 includes a cover 402. The cover 402 includes pins 404. In the embodiment shown in FIG. 4, the pins 404 may be disposed in pin channels 406 formed in the cover 402. The inner pod 400 further includes a base plate 408. The base plate 408 may include diaphragm openings 410. A diaphragm 412 may be provided in each of the diaphragm openings 410. A retaining ring 414 may be provided to secure each diaphragm 412 in its respective diaphragm opening 410.

[0046] Inner pod 400 is an inner pod of a reticle pod, such as the inner pod of reticle pod 100 shown in FIG. 1 and described above. Inner pod 400 may be sized to fit within an outer pod of a reticle pod. Inner pod 400 may be further configured to define an interior space capable of containing a reticle, such as reticle 102 described above and shown in FIG. 1.

[0047] The cover 402 is a cover included in the inner pod 400. The cover 402 includes a plurality of pins 404 extending from a surface of the cover 402 that faces the base plate 408 when the inner pod 400 is assembled. The pins 404 may have tapered or curved tips so that the pins can be inserted to a predetermined depth when received in openings in the diaphragm 412. In one embodiment, the pins 404 may be integrally formed with the cover 402. In one embodiment, the pins 404 are each disposed in a pin channel 406 formed in the cover 402. The pins 404 may be secured in the pin channels 406 by any suitable connection, such as, by way of non-limiting example, a press fit between each pin 404 and its respective pin channel 406. In one embodiment, three or more pins 404 may be provided on the cover 402. In one embodiment, four pins 404 may be provided on the cover 402. In one embodiment, the pins 404 may be disposed proximate a corner of the cover 402. In one embodiment, the pin channels 406 are openings recessed a predetermined depth from the surface of the cover 402 that faces the base plate 408 when the inner pod 400 is assembled. In one embodiment, the pin channels 406 may be through holes that extend through the entire thickness of the cover 402.

[0048] The base plate 408 is a base plate included in the inner pod 400. The base plate 408 includes a plurality of diaphragm openings 410 formed at positions corresponding to the positions of the pins 404 of the cover 402 so that the pins 404 can be received in the diaphragms 412 when the cover 402 and the base plate 408 are assembled to form the inner pod 400. The diaphragm openings 410 are openings in the base plate 408, each configured to contain a diaphragm 412. In one embodiment, the diaphragm openings 410 include a step, shoulder, or ledge recessed from the surface of the base plate 408 that faces the cover 402 when the inner pod is assembled. In one embodiment, a portion of the diaphragm opening 410 is a through-hole that extends through the entire thickness of the base plate 408. In one embodiment, the diaphragm openings 410 do not extend completely through the thickness of the base plate 408.

[0049] A diaphragm 412 is disposed in each of the diaphragm openings 410. The diaphragm 412 is configured to receive an end of one of the pins 404 when the cover 402 is assembled to the base plate 408. The diaphragm 412 is configured so that the portion that receives the end of the pin 404 can be displaced in a direction substantially perpendicular to the plane of the diaphragm 412. The diaphragm 412 can provide substantially greater resistance to movement of the portion that receives the end of the pin 404 in a direction parallel to the plane of the diaphragm 412. The diaphragm 412 can be made of any suitable material, such as, for example, steel. An example of a diaphragm 412 is shown in FIG. 5 and described in further detail below.

[0050] The retaining ring 414 is configured to retain the diaphragm 412 in the diaphragm opening 410. The retaining ring 414 may be, for example, a snap ring. The retaining ring 414 may be made of any suitable material, including a polymeric or metallic material. The retaining ring 414 may retain the diaphragm 412 against a step, shoulder, or ledge in the diaphragm opening 410. The retaining ring 414 may have any shape suitable for engaging the diaphragm opening 410 and retaining the diaphragm 412 in place within the diaphragm opening 410. In one embodiment, the retaining ring 414 may have a shape that corresponds to the shape of the diaphragm opening 410.

[0051] When the inner pod 400 is assembled by placing the cover 402 and base plate 408 together, the tapered ends of the pins 404 each engage one of the diaphragms 412. The portions of the diaphragm 412 that receive the ends of the pins 404 can move in a direction perpendicular to the diaphragm 412, allowing the inner pod 400 to be assembled with little resistance. The engagement of the pins 404 with the diaphragms 412 can restrict relative movement of the cover 402 and base plate 408, which are flush with the cover 402 or base plate 408, due to the nature of the diaphragm 412 and the difference between the resistance of the diaphragm 412 to deformation in the plane of the diaphragm 412 and the resistance of the diaphragm 412 to deformation perpendicular to the plane of the diaphragm 412. Thus, relative movement of the cover 402 and base plate 408 having components flush with the cover 402 or base plate 408 is restricted, limiting rubbing of the cover 402 against the base plate 408 when the inner pod 400 is assembled. The pin 404 and diaphragm 412 can form movement-limiting features that are separate and distinct from the first and second gross alignment features formed in the cover 402 and base plate 408, such as the gross alignment features shown in FIG. 6 and described below.

[0052] While FIG. 4 shows pin 404 extending from cover 402 and diaphragm 412 disposed in diaphragm opening 410 formed in base plate 408, it should be understood that these features may be reversed, with pin 404 instead extending from base plate 408 and diaphragm 412 instead disposed in diaphragm opening 410 formed in cover 402, with corresponding changes to the positions of other features such as pin channel 406 and retaining ring 414.

[0053] 5 shows a top view of a diaphragm in a base plate of a reticle pod, according to one embodiment. Diaphragm 500 includes a central aperture ring 502 and a plurality of spring beams 504, which may include spring beam apertures 506. Diaphragm 500 is mounted in a diaphragm aperture 508 formed in a base plate 510. Diaphragm 500 may be secured in diaphragm aperture 508 by a retaining ring 512.

[0054] Diaphragm 500 is one embodiment of diaphragm 412 discussed above. Diaphragm 500 is configured to be deformable in a direction perpendicular to the plane of diaphragm 500 and to provide substantially greater resistance to deformation in a direction parallel to the plane of diaphragm 500. Diaphragm 500 includes a central aperture ring 502 configured to receive the tip of a pin, such as pin 404 described above and shown in FIG. 4. Central aperture ring 502 may be configured to engage the tip of the pin along a tapered or curved portion. Central aperture ring 502 may have any shape suitable for receiving and engaging a pin, such as the circular aperture shown in FIG. 5. Central aperture ring 502 is supported by spring beams 504. Spring beams 504 may be radially distributed around central aperture ring 502. The spring beams 504 can have any shape suitable to allow deformation that moves the central aperture ring 502 perpendicular to the plane of the diaphragm 500. In one embodiment, the spring beams 504 each include their own respective spring beam aperture 506. The spring beams can each be connected to the outer periphery of the diaphragm 500 (covered by a retaining ring 512, not shown).

[0055] Diaphragm opening 508 is an opening formed in base plate 510. Diaphragm opening 508 can be any shape suitable for accommodating diaphragm 500. In one embodiment, diaphragm opening 508 is recessed from the surface of reticle pod 510 and includes a step, shoulder, or ledge sized to allow diaphragm 500 to rest on the step or ledge. In one embodiment, diaphragm opening 508 is recessed from the surface of reticle pod 510 with a predetermined depth. In one embodiment, diaphragm opening 508 includes at least a portion drilled through the entire thickness of base plate 510.

[0056] The retaining ring 512 is configured to retain the diaphragm 500 within the diaphragm opening 508. The retaining ring 512 can have any shape suitable to correspond to the outer periphery of the diaphragm 500 and fit within at least a portion of the diaphragm opening 508. In one embodiment, the retaining ring 512 is a snap ring. In one embodiment, the retaining ring 512 can press the diaphragm 500 against a step, shoulder, or ledge formed in the diaphragm opening 508 to secure the position of the diaphragm 500 in place.

[0057] FIG. 6 shows a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. Reticle pod 600 includes a cover 602. Cover 602 includes a travel limiting pin 604. Travel limiting pin 604 may be disposed in a travel limiting channel 606 provided in cover 602. Reticle pod 604 further includes a base plate 608. Base plate 608 includes a travel limiting cup 610. In the embodiment shown in FIG. 6, travel limiting cup 610 is provided in an insert 612, which is provided in a recess 614 formed in base plate 608. Auxiliary contact surface 616 may also be provided. In the embodiment shown in FIG. 6, first gross alignment feature 618 and second gross alignment feature 620 may also be seen.

[0058] Inner pod 600 is an inner pod of a reticle pod, such as the inner pod of reticle pod 100 shown in FIG. 1 and described above. Inner pod 600 may be sized to fit within an outer pod of a reticle pod. Inner pod 600 may be further configured to define an interior space capable of containing a reticle, such as reticle 102 described above and shown in FIG. 1.

[0059] The cover 602 is a cover included in the inner pod 600. The cover 602 includes travel limiting pins 604. In one embodiment, the cover 602 includes at least three travel limiting pins 604. In one embodiment, the cover 602 includes four travel limiting pins 604. In one embodiment, the cover 602 includes a travel limiting pin 604 proximate each corner of the cover 602. The travel limiting pins 604 protrude from a surface of the cover 602 that faces the base plate 608 when the inner pod 600 is assembled. The travel limiting pins 604 may each have a tapered or curved tip. In one embodiment, the travel limiting pins 604 may be integrally formed with the cover 602. In one embodiment, the travel limiting pins 604 may be disposed in a travel limiting channel 606. The travel limiting pins 604 may be retained in the travel limiting channel 606 by any suitable method. In one embodiment, the travel-limiting pin 604 is press-fit into the travel-limiting channel 606. In one embodiment, the travel-limiting channel 606 is recessed from the surface of the cover 602. In one embodiment, the travel-limiting channel 606 is a through-hole that extends through the entire thickness of the cover 602.

[0060] The base plate 608 is the base plate of the inner pod 600. The base plate 608 includes movement limiting cups 610 each configured to receive one of the movement limiting pins 604 on the cover 602. The movement limiting cups 610 can be positioned such that their relative positions correspond to the positions of the movement limiting pins. In one embodiment, the movement limiting cups are features formed in the base plate 608 itself, such as shaped cutouts from the base plate 608. In one embodiment, the movement limiting cups 610 are each configured to provide multiple discrete points of contact with the movement limiting pins 604 when the movement limiting pins 604 are received in the movement limiting cups 610 when the inner pod 600 is assembled. In one embodiment, the movement limiting cups 610 can include multiple angled portions configured to provide points of contact with corresponding movement limiting pins 604. In one embodiment, the movement limiting cups 610 can each have a rectangular shape on the surface of the base plate 608. In one embodiment, the movement limiting cup 610 is formed in an insert 612 configured to rest within a recess 614 formed in the base plate 608. The recess 614 is configured to receive and retain the insert 612. In one embodiment, the recess 614 retains the insert via a press fit. The insert 612 may be made from any suitable material, including metal, coated metal, polymeric material, etc., so long as the insert 612 is capable of restricting movement of the movement limiting pin and can withstand any processes in which the inner pod 600 will be used. The recess 614 and the insert 612 may have a generally rectangular shape. In one embodiment, the long axes of these rectangular shapes may be angled with respect to the sides of the cover 602 or the base plate 608 such that the long axes of the recess 614 and the insert 612 are not parallel to any of the sides of the cover 602 or the base plate 608.

[0061] Auxiliary contact surfaces 616 may be provided on base plate 608 to provide additional contact with travel-limiting pins 604. In one embodiment, auxiliary contact surfaces 616 extend above the surface of base plate 608. In one embodiment, auxiliary contact surfaces 616 may be integral with base plate 608. In one embodiment, auxiliary contact surfaces 616 are included in insert 612. Auxiliary contact surfaces 616 may each be configured to contact a side of one of travel-limiting pins 604.

[0062] FIG. 6 further illustrates gross alignment features included in inner pod 600. While not visible in certain views of FIGS. 1-4 , it should be understood that inner pods 110, 200, 300, and 400 also include first and second gross alignment features, such as first and second gross alignment features 618, 620 visible in FIG. 6 . First and second gross alignment features 618 and 620 are configured to interface with one another to guide assembly of inner pod 600 and to assist in securing cover 602 to base plate 608. In one embodiment, first and second gross alignment features 618, 620 engage with one another prior to engagement of travel-limiting features, such as travel-limiting pin 604 and travel-limiting cup 610. In one embodiment, the first and second gross alignment features 618, 620 engage with one another after engagement of a travel limiting feature, such as the travel limiting pin 604 and the travel limiting cup 610. In one embodiment, the first and second gross alignment features 618, 620 engage with one another simultaneously with engagement of a travel limiting feature, such as the travel limiting pin 604 and the travel limiting cup 610.

[0063] First gross alignment feature 618 may be a protrusion, for example, a protrusion extending from cover 602. First gross alignment feature 618 may be integrally formed with cover 602 or may be a pin disposed in and extending from a channel formed in cover 602, as shown in FIG.

[0064] The second gross alignment feature 620 can be a channel configured to receive the first gross alignment feature 618. The second gross alignment feature can be configured such that there is more space than is necessary to receive the first gross alignment feature 618 to allow relative movement of the cover 602 and base plate 608 such that engagement of the first and second gross alignment features 620 is flush with the cover 602 or base plate 608. The first and second gross alignment features 618, 620 can optionally be swapped such that the first gross alignment feature 618 protrudes from the base plate 608 and the second gross alignment feature 620 is formed in the cover 602. The interface of the first gross alignment feature 618 and the corresponding second gross alignment feature 620 may be such that a relative movement of up to 0.2 millimeters (mm) flush with the cover or base plate may be permitted before the interface of the first and second gross alignment features 618, 620 prohibits further movement.

[0065] When the inner pod 600 is assembled by joining the cover 602 to the base plate 608, each of the travel limiting pins 604 interfaces with each of the multiple contact surfaces provided by the travel limiting cup 610 and the auxiliary contact surfaces 616. The engagement of each of the travel limiting pins 604 with those multiple contact surfaces can restrict movement of the cover 602 relative to the base plate 608 such that relative movement of the cover 602 or any surface flush with the base plate 608 is restricted.

[0066] While the inner pod 600 shown in FIG. 6 includes a travel limiting pin 604 on the cover 602 and a travel limiting cup 610 on the base plate 608, it should be understood that these features may be interchanged such that the travel limiting pin 604 instead protrudes from the base plate 608, the travel limiting cup is on the cover 602, and any corresponding features, such as the travel limiting channel 606, the recess 614, and the auxiliary contact surface 616, are correspondingly interchanged from the cover 602 to the base plate 608, and vice versa.

[0067] Although the movement limiting features are shown individually in inner pods 200, 300, 400, and 600 in Figures 2, 3, 4, and 6, respectively, it should be understood that the individual movement limiting features shown in those figures may be combined, for example, by including corresponding movement limiting features from two or more of inner pods 200, 300, 400, and / or 600 in the cover and base plate of another inner pod.

[0068] 7 illustrates a base plate for an inner pod of a reticle pod, according to one embodiment. Base plate 700 includes a plurality of slots 702 formed in a surface 704 facing the cover of the inner pod. Slots 702 are each lined by a flexible member 706 on an opposite side of base plate 700, the flexible member having a contact surface 708.

[0069] Slots 702 are formed in base plate 700. The slots 702 extend through the body of base plate 700. The slots 702 are sized to receive pins on a cover used with base plate 700 to form an inner pod, such as cover 802 with pins 804 described below and shown in FIG. 8 . The slots 702 are positioned so that at least a portion of each slot extends from an area where a reticle will be positioned when the reticle is stored in an inner pod that includes base plate 700. Each of the slots 702 has a major axis. In one embodiment, base plate 700 includes three slots 702. The slots 702 can have any suitable two-dimensional shape, such as a circular hole, a rectangle, an oval, a stadium, or a capsule shape. In one embodiment, the slots 702 include straight sides perpendicular to the plane of base plate 700. In one embodiment, the slots 702 have sides that are angled with respect to the plane of the base plate such that the slots 702 taper as they extend through the base plate 700. The slots 702 may include lead-ins to facilitate insertion of a pin into each of the slots 702. In one embodiment, the slots 702 include a bevel and / or a radius on the side of the slot 702 that faces a cover used with the base plate 702. In one embodiment, the major axes of each of the slots 702 extend in different directions. In one embodiment, the slots 702 are positioned such that the slots 702 are mirror-aligned with a kinematic coupling groove formed in the side of the base plate 700 that faces the surface 700. In one embodiment, the base plate 700 includes four or more slots 702. In one embodiment, the major axes of at least two of the slots 702 are collinear or parallel. In one embodiment, the major axes of the slots 702 in the base plate 700 intersect at the center of the base plate 700.

[0070] The flexible member 706 is provided so that pins inserted into the slots 702 each contact the flexible member 706 after passing through the body of the base plate 700 through which the slots 702 extend. The flexible member 706 may comprise a resilient polymer material, a metal spring arm, or any other suitable flexible material that allows the contact surface 708 of the flexible member to deflect when the pin contacts the contact surface 708. The contact surface 708 is a portion of the flexible member 706 configured to engage with the pin of the cover to restrict movement of the pin along the extension direction of the slot 702 that the flexible member lines, thereby limiting movement of the cover including the pin. The flexible member 706 may be flexible so that the contact surface 708 engages the pin at a tapered, angled end, or any other such suitable surface formed on the pin. The flexible member 706 can have a flexibility selected such that the deflection of the contact surface 708 is controlled to match the depth to which the pin protrudes through the slot 702 when the inner pod including the base plate 700 is assembled.

[0071] 8 shows a cross-sectional view of an inner pod of a reticle pod, according to one embodiment. Inner pod 800 includes a cover 802 including pins 804. Pins 804 include ends 806. Inner pod 800 further includes a base plate 808 including slots 810. A flexible member 812 is provided in each of slots 810. Each flexible member includes a contact surface 814 and a flexible member retention feature 816. Flexible member retention feature 816 is configured to engage with a base plate retention feature 818 formed in base plate 808.

[0072] The cover 802 is a reticle pod cover configured to form an inner pod 800 that includes an interior space configured to accommodate a reticle when combined with a base plate 808. The cover 802 includes pins 804. The pins 804 may be positioned so that the pins 804 do not extend through the inner pod 800 at a location where a reticle may reside when stored within the inner pod 800. The pins 804 extend a length such that the pins 804 can extend through the slots 810 to contact the contact surfaces 814 when the inner pod 800 is assembled. One or more pins 804 may be provided for each slot 810 included in the corresponding base plate 808; for example, three pins 804 are provided in a cover 802 used with a base plate 700 having three slots 702, as described above and shown in FIG. 7 .

[0073] Each of the pins 804 includes an end 806. The end 806 may be shaped to engage a contact surface 814 provided by the flexible member 812 in the respective slot 810. In one embodiment, the end 806 is tapered. In one embodiment, the end 806 includes an angled surface that is not parallel or perpendicular to the direction of extension of the pin 804. In one embodiment, the end 806 comes to a point. When the end 806 engages the contact surface 814, movement of the pin 804 along the slot 810 may be restricted by contact of the end 806 or a portion of the end 806 with the contact surface 814.

[0074] The base plate 808 is the base plate of the inner pod 800. The base plate 808 includes slots 810 formed therein. The slots 810 extend through the thickness of the base plate 808. Each slot 810 is configured to receive a corresponding pin 804 provided on the cover 802. The slots may be included in any suitable number and arrangement, as described above for the slots 702 shown in FIG. 7 . A flexible member 812 is provided on a side of the base plate 808 opposite the cover 802 when the inner pod 800 is assembled. The flexible member 812 may be shaped to cover at least a portion of the opening formed by the slot 810. The flexible member 812 covers the opening formed by the slot 810 on the side opposite the cover 802. The flexible member 812 provides a contact surface 814 configured to engage with the pin 804 to restrict movement of the cover 802 along the direction of extension of the slot 810. The flexible member 812 is configured such that the contact surface 814 can be deflected by contact with the pin 804. The contact surface 814 and the deflection of the contact surface 814 can be configured to engage features on the end 806 of the pin 804, such as angled surfaces, tapers, etc., to restrict translational movement of the pin 804 along the slot 810, thereby retaining the cover 802 in a particular position. Retention of the cover 802 via engagement of the pin 804 with the slot 810 and contact surface 814 can thereby restrict translational movement of the cover 802 relative to the base plate 808 such that alignment is maintained and sliding and particle generation at the interface of the cover 802 and base plate 808 is reduced.

[0075] The flexible member 812 includes a flexible member retaining feature 816, and the base plate 808 includes a base plate retaining feature 818. The flexible member retaining feature 816 and the base plate retaining feature 818 can be any corresponding features suitable for securing the flexible member 812 to the base plate 808. In one embodiment, the base plate retaining feature 818 can be a groove or hole configured to receive a protrusion provided on the flexible member 812 as the flexible member retaining feature 816. In one embodiment, the flexible member retaining feature can be press-fit into the base plate retaining feature 818. In one embodiment, the groove or hole can receive an undercut configured to receive a flange, tab, or other such protrusion from the flexible member retaining feature 816. In one embodiment, an adhesive can be provided to secure the flexible member retaining feature 816 to the base plate retaining feature 818.

[0076] Aspects:

[0077] It should be understood that any of the following aspects may be combined with any other of the following aspects.

[0078] Aspect 1. An inner pod including a base plate and a cover, The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: an alignment-retaining cutout formed in one of the cover or the base plate, and an elastic body disposed in the alignment-retaining cutout, the elastic body configured to contact both the base plate and the cover when the inner pod is assembled; the plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force; Reticle pod.

[0079] Aspect 2. An inner pod including a base plate and a cover, The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: a mating pin extending from one of the cover or the base plate and a resilient contact surface provided on the other of the cover or the base plate, the mating pin configured to contact the resilient contact surface when the inner pod is assembled; the plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force; Reticle pod.

[0080] Aspect 3. A reticle pod according to aspect 2, wherein the resilient contact surface is provided on an elastic body, the elastic body including a hollow portion opposite a surface configured for the mating pin to contact the resilient contact surface.

[0081] Embodiment 4. A reticle pod according to any one of embodiments 2 to 3, wherein each of the mating pins is disposed in a mating pin channel, each mating pin channel being formed in one of the cover or the base plate.

[0082] Aspect 5. An inner pod including a base plate and a cover, The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: a diaphragm disposed in one of the cover or the base plate; a pin extending from the other of the cover or the base plate, the pin configured to contact the diaphragm when the inner pod is assembled; and Including, the diaphragm has a resistance to deformation in a direction flush with the cover or base plate that is greater than the resistance to deformation in a direction perpendicular to the plane of the cover or base plate; each of the pins having a taper at an end configured to contact one of the plurality of diaphragms; the plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force; Reticle pod.

[0083] Embodiment 6. A reticle pod as described in embodiment 5, wherein each of the movement-limiting features includes an alignment-retaining cutout configured to accommodate a diaphragm and a retaining ring configured to retain the diaphragm in the alignment-retaining cutout.

[0084] Embodiment 7. The reticle pod of embodiment 5 or 6, wherein the pins are disposed in pin channels formed in one of the cover or base plate.

[0085] Aspect 8. An inner pod including a base plate and a cover, The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: a travel limiting pin extending from one of the cover or the base plate; a movement limiting cup disposed in the other of the cover or the base plate; Including, the travel limiting pin is configured to be contacted by a plurality of different surfaces of the travel limiting cup when the inner pod is assembled; the plurality of movement-limiting features are configured such that when a force having a component parallel to the plane of the base plate or the cover is applied to the inner pod, at least one of the plurality of movement-limiting features provides resistance to the force before the at least one gross alignment feature provides resistance to the force; Reticle pod.

[0086] Embodiment 9. The reticle pod of embodiment 8, wherein the movement limiting cup is formed directly into one of the cover or base plate.

[0087] Embodiment 10. The reticle pod of embodiment 8 or 9, wherein the movement limiting cup is formed in the insert, and the insert is configured to be received in a recess formed in one of the cover or base plate.

[0088] Aspect 11. A method for securing an inner pod of a reticle pod, comprising: engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate; Engaging each of a plurality of movement-limiting features provided on one of the cover or the base plate with the other of the cover or the base plate, the plurality of movement-limiting features including a plurality of alignment-retaining cutouts and a plurality of resilient bodies, each resilient body disposed in one of the alignment-retaining cutouts, and each of the plurality of resilient bodies configured to contact both the base plate and the cover when the inner pod is assembled; and Equipped with When a force having a component flush with the cover or base plate acts on the inner pod, engagement of the travel-limiting feature provides resistance to the component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. method.

[0089] Aspect 12. A reticle is disposed within an inner pod, and the method comprises: placing an inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod; The inner pod is subjected to an extreme ultraviolet process. 12. The method of embodiment 11, further comprising:

[0090] Aspect 13. A method for securing an inner pod of a reticle pod, comprising: engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate; engaging each of a plurality of movement-limiting features on one of the cover or the base plate with the other of the cover or the base plate, the plurality of movement-limiting features including a plurality of mating pins extending from the one of the cover or the base plate and a plurality of resilient contact surfaces on the other of the cover or the base plate, each of the plurality of mating pins configured to contact one of the resilient contact surfaces; Equipped with When a force having a component flush with the cover or base plate acts on the inner pod, engagement of the travel-limiting feature provides resistance to the component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. method.

[0091] Aspect 14. A reticle is disposed within an inner pod, and the method comprises: placing an inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod; The inner pod is subjected to an extreme ultraviolet process. 14. The method of embodiment 13, further comprising:

[0092] Aspect 15. A method for securing an inner pod of a reticle pod, comprising: engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate; each of a plurality of movement-limiting features provided on one of the cover or the base plate engaging with the other of the cover or the base plate, the plurality of movement-limiting features comprising: a plurality of diaphragms, each of the plurality of diaphragms disposed in one of the cover or the base plate; a plurality of pins extending from the other of the cover or the base plate, each of the plurality of pins configured to contact one of the plurality of diaphragms when the inner pod is assembled; engaging each of the plurality of movement-limiting features with the other of the cover or the base plate, Equipped with each of the plurality of diaphragms having a resistance to deformation in a direction coplanar with the cover or base plate that is greater than the resistance to deformation in a direction perpendicular to the plane of the cover or base plate; each of the pins having a taper at an end configured to contact one of the plurality of diaphragms; When a force having a component flush with the cover or base plate acts on the inner pod, engagement of the travel-limiting feature provides resistance to the component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. method.

[0093] Aspect 16. A reticle is disposed within an inner pod, and the method comprises: placing an inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod; The inner pod is subjected to an extreme ultraviolet process. 16. The method of embodiment 15, further comprising:

[0094] Aspect 17. A method for securing an inner pod of a reticle pod, comprising: engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate; each of a plurality of movement-limiting features provided on one of the cover or the base plate engaging with the other of the cover or the base plate, wherein the plurality of movement-limiting features: a plurality of travel limiting pins extending from one of the cover or the base plate; a plurality of movement limiting cups disposed in the other of the cover or the base plate; engaging each of the plurality of movement-limiting features with the other of the cover or the base plate, Equipped with each of the plurality of travel limiting pins is configured to be contacted by a plurality of different surfaces of one of the plurality of travel limiting cups when the inner pod is assembled; When a force having a component flush with the cover or base plate acts on the inner pod, engagement of the travel-limiting feature provides resistance to the component of the force before engagement of the cover gross alignment feature with the base plate gross alignment feature provides resistance to the component of the force. method.

[0095] Aspect 18. A reticle is disposed within the inner pod, and the method comprises: placing an inner pod within an outer pod of the reticle pod and securing the outer pod to seal the reticle pod; The inner pod is subjected to an extreme ultraviolet process. 18. The method of embodiment 17, further comprising:

[0096] Aspect 19. An inner pod including a base plate and a cover, The inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: a pin extending from the cover at a side of the cover configured to face the base plate when the inner pod is assembled; a slot formed in the base plate, the slot configured to receive the pin; a flexible member configured to cover the slot on a side of the base plate opposite the cover when the inner pod is assembled, the flexible member including a contact surface configured to be contacted by an end of a pin, the flexible member configured such that the contact surface can be deflected by contact with the pin; Includes a reticle pod.

[0097] Aspect 20. The reticle pod of aspect 19, wherein the inner pod includes at least three of the movement-limiting features.

[0098] Embodiment 21. The reticle pod of embodiment 20, wherein the major axis of each slot extends in a different direction than the major axes of all other slots.

[0099] Embodiment 22. The reticle pod of embodiment 19, further comprising a base plate retention feature formed in the base plate, wherein the flexible member includes a flexible member retention feature configured to engage with the base plate retention feature.

[0100] The examples disclosed in this application are to be considered in all respects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims, rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Claims

1. A reticle pod having an inner pod including a base plate and a cover, the inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: a mating pin extending from one of the cover or the base plate and a resilient contact surface provided on the other of the cover or the base plate, the mating pin configured to contact the resilient contact surface when the inner pod is assembled; the at least one gross alignment feature comprises: a first gross alignment feature having a protrusion extending from the cover; and a second gross alignment feature on the base plate having a channel configured to receive the first gross alignment feature; the resilient contact surface is provided on an elastic body, the resilient body including a hollow portion opposite a surface where the mating pin is configured to contact the resilient contact surface; the plurality of movement-limiting features are configured such that when a force is applied to the inner pod in a direction parallel to the plane of the base plate or the cover, at least one of the plurality of movement-limiting features provides a resistance greater than the force in a direction perpendicular to the plane of the base plate or the cover. Reticle pod.

2. A reticle pod having an inner pod including a base plate and a cover, the inner pod includes at least one gross alignment feature and a plurality of movement-limiting features, each of the plurality of movement-limiting features comprising: a movement limiting pin extending from one of the cover or the base plate; a movement limiting cup disposed in the other of the cover or the base plate; an auxiliary contact surface extending above the surface of the base plate and configured to contact a side surface of the movement limiting pin; Including, the travel limiting pin is configured to be contacted by a plurality of different surfaces of the travel limiting cup when the inner pod is assembled; the at least one gross alignment feature comprises: a first gross alignment feature having a protrusion extending from the cover; and a second gross alignment feature on the base plate having a channel configured to receive the first gross alignment feature; the plurality of movement-limiting features are configured such that when a force is applied to the inner pod in a direction parallel to the plane of the base plate or the cover, at least one of the plurality of movement-limiting features provides a resistance greater than the force in a direction perpendicular to the plane of the base plate or the cover. Reticle pod.

3. 1. A method for securing an inner pod of a reticle pod, comprising: engaging one or more gross alignment features included in one of the cover and the base plate with the other of the cover and the base plate; engaging each of a plurality of movement-limiting features on one of the cover or the base plate with the other of the cover or the base plate; Including, the plurality of movement-limiting features include a plurality of alignment-retaining cutouts and a plurality of resilient bodies, each resilient body disposed in one of the alignment-retaining cutouts, and each of the plurality of resilient bodies configured to contact both the base plate and the cover when the inner pod is assembled; the one or more gross alignment features comprising: a first gross alignment feature having a protrusion extending from the cover; and a second gross alignment feature in the base plate having a channel configured to receive the first gross alignment feature; each of the plurality of elastic bodies includes a hollow portion on the opposite side of a surface that contacts the base plate and the cover; when a force acts on the inner pod in a direction parallel to the plane of the cover or base plate, the engagement of the movement-limiting feature provides a resistance greater than the force in a direction perpendicular to the plane of the base plate or cover. method.

4. A reticle is placed within the inner pod, and the method comprises: placing the inner pod within an outer pod of the reticle pod and securing the outer pod to enclose the reticle pod; subjecting said inner pod to an extreme ultraviolet process; The method of claim 3 further comprising:

Images