The present invention relates to apparatus and methods which support fabricators with routinely replaceable processing tools and one or more cleanspaces.
A known approach to cleanspace-assisted fabrication of materials such as semi-conductor substrates, is to assemble a manufacturing facility as a “cleanroom.” In such cleanrooms, processing tools are arranged to provide aisle space for human operators or automation equipment. Exemplary cleanroom design is described in: “Cleanroom Design Second Edition,” edited by W. Whyte, published by John Wiley & Sons, 1999, ISBN 0-471-94204-9, (herein after referred to as “the Whyte text”).
Cleanroom design has evolved over time to include locating processing stations within clean hoods. Vertical unidirectional air flow can be directed through a raised floor, with separate cores for the tools and aisles. It is also known to have specialized mini environments which surround only a processing tool for added space cleanliness. Another known approach includes the “ballroom” approach, wherein tools, operators and automation all reside in the same cleanroom.
Evolutionary improvements have enabled higher yields and the production of devices with smaller geometries. However, known cleanroom design has disadvantages and limitations.
For example, as the size of tools has increased and the dimensions of cleanrooms have increased, the volume of cleanspace that is controlled has concomitantly increased. As a result, the cost of building the cleanspace, and the cost of maintaining the cleanliness of such cleanspace, has increased considerably.
Tool installation in a cleanroom can be difficult. The initial “fit up” of a “fab” with tools, when the floor space is relatively empty, can be relatively straight forward. However, as tools are put in place and a fab begins to process substrates, it can become increasingly difficult and disruptive of job flow, to either place new tools or remove old ones. It would be desirable therefore to reduce installation difficulties attendant to dense tool placement while still maintaining such density, since denser tool placement otherwise affords substantial economic advantages relating to cleanroom construction and maintenance.
Another area of evolutionary improvement has come with improvements in robotics. Substrate processing has changed from a manually intensive process where human operators handled substrates or batches of substrates. In current cleanroom designs, many processing tools include robotics for substrate handling. In some fabricator settings, human interaction is reduced to: loading collections of substrates onto processing tools, unloading collections of substrates from processing tools and moving collections of substrates from one processing tool to another. Evolutionary advances have transitioned into cleanroom robotics which are extremely complex and therefore costly and error prone.
In some cases, in a modem semiconductor fabricator, substrates move from tool to tool in specialized carriers which contain multiple substrates. The carriers interface with appropriate automation to allow for movement of the substrates around the fab and for loading and unloading the substrates from a processing tool.
The size of substrate has increased over time as have the typical sizes of fabs. The increased size allows for economies of scale in production, but also creates economic barriers to development and new entries into the industry. A similar factor is that the processing of substrates is coordinated and controlled by hatching up a number of substrates into a single processing lot. A single lot can include, for example, 25 substrates. Accordingly, known carriers are sized to typically accommodate the largest size lot that is processed in a fab.
It would be desirable to have manufacturing facilities for cleanspace-assisted fabrication, that use less cleanspace area, permit dense tool placement while maintaining ease of installation, which permit the use of more simple robotics and which are capable of efficiently processing a single substrate.
Accordingly, the present invention provides support mechanisms for a fabrication environment that includes a cleanspace with a boundary wall and a plurality of processing tools, each having a port and a body. The processing tools can be placed with each port inside the first cleanspace and the body of each processing tool can be placed at a location peripheral to the cleanspace boundary wall, such that at least a portion of the tool body is outside the cleanspace. In addition, a single material, such as a single substrate wafer, can be processed by at least two of the plurality of tools and individually transferred from a first tool to a second tool within the integrity of the cleanspace.
The present invention can therefore include methods and apparatus for: supporting processing tools, supplying utilities to the processing tools, handling material to be processed within the cleanspace; transporting materials within the cleanspace and placing a processing tool into and out of physical communication with the cleanspace.
The accompanying drawings, that are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and, together with the description, serve to explain the principles of the invention:
The present invention relates to methods and apparatus to support a cleanspace environment within which a material, such as an integrated circuit substrate, can be processed. The support can include methods and apparatus which allow a portion of a tool used to process the material to be accessible from within a cleanspace in which the material is processed. An additional portion of the processing tool can remain outside of the cleanspace environment in which the material is processed. In addition, the present invention provides for methods and apparatus to facilitate installation, removal and maintenance of the tools used to process the material.
Reference will now be made in detail to different aspects of some preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. A Glossary of Selected Terms is included at the end of this Detailed Description.
Traditionally, when installing a processing tool into a semiconductor fabricator, riggers had to place the tool in a designated position where the tool remained in place for its entire time in the fab. The present invention provides for an alternative strategy wherein processing tools can be routinely placed and removed from a fab location.
One aspect of the present invention therefore provides for support fixtures which facilitate efficient placement, removal and replacement of a processing tool in a predefined location. Predefined tool placement in turn facilitates predefined locations for utility interconnections and predefined locations for material transfer into and out of associated tool ports. In some embodiments, a support fixture can further provide a chassis capable of receiving a processing tool and moving a processing tool from a position external to a cleanspace to an operational location wherein at least an associated processing tool port is located inside the cleanspace environment. In some respects, movement of the tool from an installation position to an operational position can be envisioned much like a cabinet drawer moving from an outward position to a closed position.
Other aspects of some embodiments of the present invention include the connection of support items for proper operation of the processing tool. For example, electrical supplies, chemicals, gases, compressed air or other processing tool support can be passed through the tool chassis support system via flexible connections. Furthermore, wired or wireless transfer of data could be supported by the chassis body. In addition, in some embodiments, a support chassis according to the present invention can include communication interfaces with safety systems to provide safe operation and safe removal and replacement.
Referring now to
In
In some embodiments, physical tabs 120 may stick out of the chassis top plate 110. The physical tabs 120 may serve one or more purposes. As a physical extension, the tabs 120 will have a corresponding indentation (not illustrated) in the mating plate or a surface of a tool body 201 to be placed on the tabs 120. As the tool body 201 is lowered over the chassis 110, the tool body 201 will reach a location as defined by tabs 120. In some embodiments, the tabs 120 can additionally provide electrical connection between the chassis top plate 110 and the tool body 201. Electrical connection can serve one or more of the purposes of: electrical power and electrical data signal.
In some embodiments, a wireless interface 123 can provide wireless electrical connection between the tool body and the chassis. The wireless interface 123 can be redundant to hardwire data connections or take the place of hardwire data connection. The wireless interface can also be utilized for other electrical connections, as discussed for items. In some embodiments, a wireless coupling 123 can provide one or both of electrical power and data communication.
Connections for non-electrical utilities 121 can also be provided, as discussed more fully below in the section entitled Utility Flange Connectors. Fixtures 121 can be used for defining a connection, for example, of one or more of: gas, vacuum, fluids waste lines, compresses air, deionized water, chemicals and the like. Various conduits 112 can carry these utilities to the fixtures 121 and be routed, for example, through the chassis 101. The conduits 112 can be connected to appropriate facility supply systems, air flow systems and drains to provide for safe operation.
Referring now to
The present invention includes apparatus to facilitate placement of processing tool bodies 201 in a fab and the methods for using such placement. The chassis 101 design can be capable of assuming two defined positions; one extended position places an interface plate external to the environment that the tool assumes when it is processing. This allows for easy placement and removal. The other position can be the location where the tooling sits when it is capable of processing. The exact placement of the tooling afforded by the chassis 101 allows for more rational interconnection to facilities and utilities and also for the interfacing of the tool body 201 with fab automation. The chassis 101 can have automated operations capabilities that interface with the tool body and the fab operation to ensure safe controlled operation.
In another aspect of the invention, a processing tool 200 can transfer a material, such as, for example, a semiconductor substrate, in and out of a tool body 201. In
Referring now to
In still another aspect of the invention, in some embodiments, control automation can be contained within the chassis for various aspects of the operation of the chassis 101. It is within the scope of the present invention to monitor and control multiple states related to the chassis 101 via electronic included in the chassis 101. Such states can include, by way of example, a physical location of a chassis 101 in an extended or closed state. Therefore, for example, if a processing tool 200 and chassis 101 are in a closed and operational state, a technical operator issue a command to the chassis 101 to move to an extended location. Such communication could occur through a control panel 122 or through wireless communication to the chassis 101 through wireless receivers 123. Control of the processing tools can be accomplished with any known machine controller technology, including for example a processor running executable software and generating a human readable interface.
In some embodiments, a command to move to the chassis 101 to an extended location can also initiate, amongst other algorithmic functions, a check for the status of utilities connections. It is also within the scope of this invention to require any such utility connections to be rendered into a state of disconnect before the chassis 101 can proceed to an extended position.
Similarly, in some embodiments, prior to operations such as extension of a chassis 101, processing steps can determine that a tool body 201 did not contain any substrates prior to extension of the chassis 101. It is also within the scope of the present invention for communication modes included within the chassis 101 to communicate with fab wide automation systems for purposes such as tracking the location of substrates; tracking the identity of tools; and tracking the status of tools 200. If connections to a tool 200 and chassis 101 are in a proper state then the chassis can move into an extended position allowing for removal of the tool body 201 and replacement with a similar tool body 201.
In some embodiments of the present invention, a fabricator will include automation to handle substrates and control their processing. And, in many cases the substrates can move from tool to tool in a specialized carrier which contains the substrates. The specialized carriers can be transported via automation which includes automated transport systems. The carriers can thereby be presented to one or more processing tool interfaces, also referred to herein as a “port”. The automation allows for movement of the substrates around the fab and for loading and unloading the substrates from a processing tool. Substrates can include, for example and without limitation, wafers for semiconductor processing, microelectronic machines, nanotechnology, photonic, and biotechnological carriers.
A substrate processing tool port can support processing tools and handle wafers and wafer carriers in an environment attached to the tool body. The tool port can penetrate a clean space containment wall and the tool body can enable routine placement and replacement into the fabricator environment.
As described above, according to the present invention, processing tools reside with their tool bodies in a position which allows the tool body to be outside of a cleanspace with a tool port operatively attached to the tool body inside of the cleanspace. For example, embodiments can include a tool body adjacent to, or on the periphery of, a clean space of the fabricator and the tool port extending into the cleanspace. Each tool body can be removed and replaced in a standardized process and without requiring the removal of adjacent tool bodies. The present invention also anticipates the automated transfer of substrates from a first tool port of a first processing tool to a second tool port of a second processing tool, while maintaining the substrate in a clean space environment via a clean carrier.
Embodiments therefore include tool ports that are capable of receiving a carrier from the automated transport system. Each carrier can contain at least one substrate. The automated transport unloads the carriers and passes the carrier off to the processing tools automation systems. In some embodiments, the port size enables it to span a wall used for the definition of a primary clean space of the fabricator. Inside the primary clean space resides the entry area of the tool port. The tool port's body can span a distance in excess of the width of the clean space wall to allow for substrates which are unloaded from their carrier to be robotically handed off to the tool body's automation.
The novel tool port can incorporate various levels of automated carrier and substrate handling apparatus. For example, in some embodiments, the carrier and handling apparatus can include communication systems which receive data from electronic sensors monitoring each port, processing tools and transport apparatus. In another aspect, a substrate can be contained within a controlled ambient environment while it is within the storage carrier, port and processing tool.
Referring now to
In some embodiments, the tool body 604 resides in a secondary clean space which is independent of the primary clean space. Separation of the primary cleanspace and the secondary cleanspace is accomplished via a sealing mechanism 602. The sealing mechanism 602 can include, for example, a collapsible ring of material that when pushed against a sealing surface forms an atmospheric seal.
Referring now to
In some exemplary embodiments, a cassette containing a substrate 811 is loaded by a fabricator automation robot into the “mouth” of a cassette unloading apparatus 310. Inside the cassette unloading apparatus 810, the cassette can be opened, thereby exposing a substrate 811 contained there. In some embodiments, the cassette maintains a clean space environment for the substrate 811 contained in the cassette. In addition, the environment of the unloading apparatus is also a cleanspace thereby keeping the substrate 811 in a cleanspace environment after it is unloaded.
The retractable handler arm 813 extends into the cassette and secures the substrate wafer 811 with an actuated attachment mechanism, such as for example a vacuum tip. The retractable handler arm 813 is then retracted back out of the cassette unloader. In some embodiments, the retractable handler arm 813 centers over the rotation platen 814. A rotation of 814 with the arm centered would lead to the minimum amount of space required. Once the arm has rotated towards the tool body, the arm can again extend allowing the wafer to be placed in a receiving location of the tool body 604. After processing, the substrate 811 can be moved back to a receiving location and picked up by the handler 812. By reversing the above steps the substrate 811 can be transferred back to a carrier for handoff to the fabricator automation. The fabricator automation can transport the substrate to an additional processing tool for further processing by the additional tool.
According to some embodiments, while a tool body is located in the normal position, a seal is formed against the sealing surface 1002 maintaining the integrity of the cleanspace into which the tool port 1001 extends. As illustrated, the tool body 904 connected to the tool port 1001 extends away from the clean room wall 1010. In this position, the port 1001 is able to interface with transport automation 1013 situated on a rail 1012. In some embodiments, a robot arm would index from the transport automation 1013 to a correct tool port 1001 position by moving horizontally on rail 1012 while that rail moved along the vertical rail system 1011. Any other known transport automation can similarly be employed to position the tool port 1001. When transport automation 1013 is located in a programmed position, the transport automation 1012 moves forward to hand a wafer cassette to the tool port 1001.
In another aspect, the clean environment of fabricator 900 and each individual port 1001 can be facilitated by transporting equipment on the rail 1012 to a port 1001 and open the port 1001 to flow liquids or gasses over the internal surfaces of the port 1001 in order to facilitate particulate and film cleaning.
Another aspect of the present invention includes a carrier for containment of a single substrate in a clean environment. The carrier is capable of the transport of the single substrate inside and outside of an environment for processing substrate wafers. The single substrate carrier is capable of interfacing with processing equipment which is designed specifically for single substrate processing as contrasted with a semiconductor lot of 13 to 25 substrates. In some embodiments, the carrier can be loaded and unloaded by application of opposite force to its top and bottom plate for access to a substrate contained therein. Some embodiments can also include electronics for information, such as the identification and status of a wafer contained therein and for wired or wireless communication. Some embodiments can also include a carrier including environmental control equipment.
According to the present invention, a fabricator is provided for efficient production of lot size of a single wafer. Although designs of carriers exist to carry a single substrate at a time, these carriers are not made for the purpose of processing the substrates, but rather for transporting a wafer out of a processing line for testing, finishing or other purposes. The present invention provides methods and apparatus for a carrier of a single substrate wafer which maintains the substrate in a clean environment.
The novel single substrate processing carrier according to the present invention can incorporate various levels of automation to interface with a modem fabrication facility. For example. according to the present invention, a single substrate carrier can include electronic circuitry for communication of data from the carrier to other systems that can include, for example, processing tools and fabricator wide automation systems. Furthermore, in some embodiments, single substrate processing carrier can provide and maintain environmental control of the single substrate stored. Environmental control can include, for example, temperature and humidity control.
In another aspect, since a single substrate is the minimum entity size that can be processed at a time; a single wafer carrier according to the present invention can serve the purposes of both a processing carrier in a fabricator environment; and, a shipping carrier external to the environment. Further embodiments can also include a single substrate carrier which allows for single carrier to store a substrate in processing of the substrate, test of the substrate, as well as packaging and diagnostic environments for the substrate.
Referring now to
According to the present invention, during containment in the carrier 1101, substrate, 1140, resides in a contained clean environment; and is able to be removed and replaced from the clean environment without violating the integrity of the clean environment. Therefore, the present invention provides for an external handling unit engaging the top plate 1120 and the bottom plate 1124 and moving them apart. During such movement, the springs 1110 deflect allowing for separation of end sides 1130-1131 from an attached panel, such as the bottom plate 1124. Two lateral sides 1150 and 1151 and pieces of the other sides 1132 remain fixed to the bottom plate 1124, while sides 1131 and 1133 remain fixed to the top plate 1120. Sealing material, such as a pliable synthetic, silicone or a foam material can border the corresponding surfaces of the top plate 1120 and bottom plate 1120 where the non-attached sides 1131, 1133 make contact.
A set of rails 1123 within the carrier 1101 can provide support for substrate item 140. A set of sloped surfaces attached to the rails 1121 facilitate the location of the substrate by transfer automation in a fab (not shown). The force of springs 1110 can return the top plate 1120 and the bottom plate 1124 to their respective storage positions. In the storage position, the various sealing surfaces 1122 are placed in a closed position. A securing device, such as, for example, a set of clips (not illustrated) can secure the top edge of a substrate 1140 placed within the carrier 101 and hold the substrate 140 in place while it is contained within the carrier 1101.
Referring now to
An alternative embodiment is shown in
The rails, 1510 and pocket 1512 can be affixed to the bottom plate 1511 to allow a gap to be formed underneath the substrate. A handling arm can extend into the gap and removably attach to the substrate, for example by using a vacuum tip. The handling arm can lift the substrate and with horizontal movement of the arm retract out of the pocket. After retraction of arm, the carrier resumes a closed position under the action of the springs 1514.
Referring now to
Referring now to
In some embodiments, an additional aspect includes a set of vent holes 1720 that are located in the top plate 1710 of the carrier. The vent hole can allow for equipment to control the ambient temperature of the substrate to be attached as an integral part of the carrier.
A side view of an open carrier 1801 is shown in
Referring now to
Addition of communication and power entities can also be incorporated into the various carrier designs. Specific placement of such entities is not limited; however, for the purpose of illustration the embodiments illustrated in
Embodiments of the carrier innovation have been depicted for illustration in the various figures with springs shown as bands of material. The generality of the design should be apparent to encompass various types of spring-like material. To illustrate such a variation,
In various other aspects of the present invention, carriers according to the present invention can be used in the processing of: semiconductor substrates, microelectronic machines, nanotechnology, photonic, and biotechnological applications. Equipment can be incorporated into ports of processing tools to allow for the opening and closing of the carrier. Since substrates can also be transported in the carrier, stand-alone units for the loading and unloading of substrates without the presence of a processing tool are also within the scope of the present invention. Since the clean environment of the carrier can need to be maintained, it can also be expected that equipment that can clean the carrier can be made consistent with these design concepts. Stand-alone units that open the single substrate carrier and flow liquids or gasses over the internal surfaces to effect particulate and film cleaning are also within the scope of the present invention.
When installing a processing tool into a semiconductor fabricator, there are a number of different connections which need to be made to provide utilities, data connections and materials through conduits from the fabrication facility support infrastructure to the individual processing tools. In that traditional processing tools reside in their respective places, typically for the life of the tool, historically there has not been standardized accommodation for an organized placement of these connections in a manner that allows them to be quickly coupled. However, the present invention anticipates routine placement and replacement of processing tools and therefore provides for quick coupling and uncoupling of multiple connections. Specifically, the present invention provides methods an apparatus which allow for the repeatable removal and replacement of processing tooling without the need to weld, glue or otherwise permanently reconstitute conduit connections during each replacement.
In another aspect of the present invention, a physical framework is provided for quick standardized connections of materials and utilities to processing tools. Each processing tool can be conceptualized as a “Box” with various processes and operations occurring inside the box. Particular processes and operations are generally unimportant to this disclosure, except in that they define the need for the input and output of materials, utilities, data connections and waste relative to each “Box” to support its operation. The general classes of the materials, utilities and waste relevant to this concept can be liquid chemicals, gaseous chemicals, vacuum, cooling liquids, and utility gas flows for cooling or exhaust.
General classes of materials can each have their own set of technical needs based upon requirements for safe operation, process integrity, cost effectiveness or other related concern. A first class for discussion can include gaseous chemicals. Such chemicals can be further sub-classified for example as inert, reactive, toxic or pyrophoric or a combination of these. Each sub-classification can have the property of being provided under an elevated pressure with high degrees of purity. Thus a means of quickly coupling and decoupling gaseous chemicals will need to address various needs and properties of each classification.
In
Electronic monitoring of the vacuum state can be used to facilitate safety, wherein any change in the vacuum state can be assessed to determine if the change denotes a safety hazard or an indication of impurities mixing with gases or materials passing through the flange 2101. The application of a vacuum can facilitate safe use of the flange 2101 during operation and through detection of any leaks in sealing surfaces. Furthermore, miniscule leaks that may be small enough to effect process cleanliness but not large enough for general detection will not result in foreign gases being introduced.
On an inner side of channel 2112 is a second surface 2115 on which multiple conduit sealing junctions 2116 can be arrayed. Each sealing junction 2116 can include a pliable seal, O-ring, brass ring or other interface device capable of forming a gaseous seal. In some embodiments, each sealing junction 2116 can be constructed so that it has the same planar height as the external sealing surface 2110. Embodiments with essentially planar sealing surface heights will invoke a positive sealing aspect with O-ring 2111 and at the same time force individual gas line O-rings 2116 to seal.
A second radial sealing surface 2115 can terminate with a second channel 2119. Channel 2119 can be evacuated with a port 2118 to establish a vacuum condition on either side of the gas line conduit sealing region. In this manner an individually sealed conduit line 2113 (
In some embodiments, safe operations can further be enhanced by the incorporation of an electronic ID tag (not illustrated). The tags can uniquely identify each flanging mechanism half. Control electronics capable of interacting with the ID tags can then ensure that the gas lines that will be connected are appropriate.
Referring now to
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A connector 2801 to chemical lines on the tool side of the interface can connect an output line 2821 of a flange 2810 according to the present invention to a processing tool supply line. The flanging device will have a tool side flange 2810 and a facilities side flange 2811 as well. Chemical input to the flange will likewise be done with line 2812 and connector 2813. Instead of the vacuum shown in the gas devices a chemical drain connection can be used to both detect and safely contain leaks. Item 2831 is indicated to show a channel connection that will connect tube 2832 to a drain channel (not shown in
Referring now to
In some embodiments, automated chemical detectors can provide an alert to a situation of a chemical leak in the sealing surface 2928. In an analogous fashion to the vacuum system with gasses such detectors can also be operative to automatically shut off the chemical flow to the flange with appropriate valves.
Referring now to
To illustrate a quick disconnect multiport,
It is to be understood, that although various specific embodiments have been described, including a multipart flange 3001, individual nuts as shown as item 2410 in
Referring now to
Some embodiments of the present invention which relate to the specific application of semiconductor fabrication have been described in order to better demonstrate various useful aspects of the invention. However, such exemplary descriptions are not meant to limit the application of the inventive concepts described herein in any way. Embodiments may therefore include, for example, applications in research and generation of: pharmaceutical products, nanostructure products and other applications which benefit from the availability of cleanspace and multiple processing tools.
While the invention has been described in conjunction with specific embodiments, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description.
Accordingly, this description is intended to embrace all such alternatives, modifications and variations as fall within its spirit and scope.
This application is a continuation-in part to the United States Patent Applications bearing the Ser. Nos. 11/502689, filed Aug. 12, 2006 and entitled: “Method and Apparatus to support a Cleanspace Fabricator” which claims priority to the following Provisional Applications: Provisional Application, Ser. No. 60/596343, filed Sep. 18, 2005 and entitled: “Specialized Methods for Substrate Processing for a Clean Space Where Processing Tools are Vertically Oriented”; and also Provisional Application, Ser. No. 60/596173, filed Sep. 6, 2005 and entitled: “Method and Apparatus for Substrate Handling for a Clean Space Where Processing Tools are Reversibly Removable”; and also Provisional Application, Ser. No. 60/596099, filed Aug. 31, 2005 and entitled: “Method and Apparatus for a Single Substrate Carrier For Semiconductor Processing”; and also Provisional Application, Ser. No. 60/596053 filed Aug. 26, 2005 and entitled: “Method and Apparatus for an Elevator System for Tooling and Personnel for a Multilevel Cleanspace/Fabricator”; and also Provisional Application, Ser. No. 60/596035 filed Aug. 25, 2005 and entitled: “Method and Apparatus for a Tool Chassis Support System for Simplified, Integrated and Reversible Installation of Process Tooling”; and also Provisional Application, Ser. No. 60/595935 filed Aug. 18, 2005, and entitled: “Method and Apparatus for the Integrated, Flexible and Easily Reversible Connection of Utilities, Chemicals and Gasses to Process Tooling.” The contents of each are relied upon and incorporated by reference.
Number | Date | Country | |
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60596343 | Sep 2005 | US | |
60596173 | Sep 2005 | US | |
60596099 | Aug 2005 | US | |
60596053 | Aug 2005 | US | |
60596035 | Aug 2005 | US | |
60595935 | Aug 2005 | US |
Number | Date | Country | |
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Parent | 11502689 | Aug 2006 | US |
Child | 13836182 | US |