Dual pod with guidance mechanism

Abstract

To reduce the generation of contamination particles by suppressing a lid movement of an inner pod against a base when a reticle transfer dual pod is closed in an EUV lithography process.SOLUTION: The present invention provides a dual pod (3) including an inner pod (40) and an outer pod (30). The inner pod has at least one engagement portion (i.e., a notch provided in a handle (411)) provided on the relative outer side of the inner pod. The outer pod defines a housing space that receives the inner pod. The outer pod has at least one guidance mechanism (313) provided on the relative inner side of the outer pod. The guidance mechanism is guided by the engagement part and is constrained at this engagement part to restrict the offset movement of the inner pod within the outer pod.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to reticle transport pods, particularly dual pods, and more particularly to a dual pod with guide mechanisms for the inner pod. [Background technology]

[0002] In the current extreme ultraviolet (EUV) lithography process, the reticle needs to be protected by an EUV reticle transfer pod (EUV POD). Referring to the schematic diagram shown in FIG. 1, the EUV reticle transfer pod is a dual pod (1) including an outer pod (30) and an inner pod (40). The reticle is received in the inner pod (20), which is received in the outer pod (40). The outer pod (10) has as its main components a housing (11) and a door (12), which are joined together to define a storage space. The inner pod (20) has as its main components a lid (21) and a base (22), which are joined together to define a storage space.

[0003] Once the dual pod (1) is closed, a kinematic coupling element (121) on the upwardly facing surface of the door (12) is joined to and restrains the base (22) of the inner pod (20), so that the horizontal movement of the base (22) (i.e., along the X-axis, Y-axis, and C-axis in FIG. 2) is limited. A number of pressing elements (111) on the inside of the housing (11) press against the upper surface of the lid (21) of the inner pod (20) and apply downward pressure, so that the lid (21) and the base (22) of the inner pod (20) fit together to limit the vertical movement of the lid (21) (i.e., along the Z-axis, A-axis, and B-axis in FIG. 2), further achieving the purpose of holding the inner pod (20).

[0004] However, the pressing member (111) only exerts a downward pressure in one direction along the Z axis, but cannot restrain the lid (21) of the inner pod (20) from horizontal movement (i.e., movement along the X-axis, Y-axis, and C-axis indicated by thin lines in FIG. 2). Therefore, when the dual pod (1) is subjected to an external force during transportation, the lid (21) of the inner pod (20) will experience horizontal movement, e.g., movement along the X-axis or Y-axis or deflection about the C-axis, relative to the base (22) in such a manner that the contact areas of the lid (21) and the base (22) rub against each other, generating particles and thus risking contamination.

[0005] In FIG. 3, when the lid (21) and the base (22) are fitted together, the restraining member (211) provided on one side of the lid (21) can limit the horizontal movement of the lid (21) and the base (22) along the Y-axis to, for example, 0.2 mm to 0.4 mm. However, this level of movement is still not enough to prevent particle generation. Summary of the Invention [Problem to be solved by the invention]

[0006] Thus, there is a need in the industry for a solution that inhibits movement of the inner pod lid relative to the base when the dual pod is closed. [Means for solving the problem]

[0007] One object of the present invention is to provide a dual pod, the dual pod including an inner pod, at least one engagement portion being provided relatively outside the inner pod, the dual pod further including an outer pod defining a storage space for receiving the inner pod, and at least one guide mechanism being provided relatively inside the outer pod, the guide mechanism being guided by the engagement portion and restrained at the engagement portion so that offset movement of the inner pod within the outer pod is limited.

[0008] In certain embodiments, the guide mechanism includes a guide portion and a coupling portion coupled to the guide portion, the coupling portion coupled to an interior side of the outer pod and the guide portion abutting an engagement portion of the inner pod away from the interior side of the outer pod.

[0009] In certain embodiments, the guide portion is flexible, the engagement portion is a notch, and the guide portion correspondingly deforms according to a force applied to the notch and is accordingly guided by and constrained at the notch.

[0010] In a particular embodiment, a gap with a stroke distance is provided between the guide portion and the inside of the outer pod, which serves as a tolerance to allow the guide portion to flexibly abut against the mating portion of the inner pod.

[0011] In certain embodiments, the guide portion includes mated first and second guide ribs that elastically deform in unison as the opening of the notch into which the guide ribs are inserted changes such that the first and second guide ribs are constrained to fit within the notch.

[0012] In certain embodiments, the notch has a notch edge width and the width of the guide portion is less than the notch edge width.

[0013] In a specific embodiment, the inner pod has a base and a lid joined together to define a storage space for receiving a reticle, and the outer pod has a door and a housing joined together to define a storage space, and the vertical direction of the lid is constrained by a guide mechanism to prevent the inner pod from being deflected offset relative to the axis due to an external force, and the horizontal direction of the lid is constrained by a guide mechanism.

[0014] In a particular embodiment, a flange is provided on each of two opposing faces of the lid, an engagement portion is provided on the outside of the flange, and a guide mechanism is positioned to match the flange, such that the guide mechanism is guided by and restrained at the engagement portion.

[0015] In a particular embodiment, each of two opposing surfaces of the lid is provided with a flange, the engagement portion is provided on the outside of the flange, and the guide mechanism has an inclined surface that abuts against the flange, the inclined surface extending from a top portion of the housing toward an inner wall of the housing such that the vertical and at least horizontal directions of the flange are restrained by the inclined surface.

[0016] In certain embodiments, the beveled surface and the top surface of the lid form an included angle in the range of 0.01° to 89.9°.

[0017] In a particular embodiment, a flange is provided on each of two opposing sides of the lid, the engagement portion is provided on the outside of the flange, and the guide mechanism has an inclined surface that abuts the flange, the inclined surface protruding upwardly from the inner top portion of the door such that the vertical and at least horizontal directions of the flange are restrained by the inclined surface.

[0018] In a particular embodiment, each of two opposing faces of the lid is provided with a flange, the engagement portion is provided on the outside of the flange, and the guide mechanism has at least two guide ribs arranged in parallel, the two guide ribs being formed to protrude upwardly from the inner top portion of the door, and the two guide ribs resiliently abut against the inside of the engagement portion to achieve restraint.

[0019] For a better understanding of the present invention, reference is made to the drawings and text description below. Non-limiting and non-exhaustive embodiments are described below with reference to the drawings. It should be noted that components in the drawings are not necessarily drawn to their actual size, but are instead depicted to focus on explaining the structure and principles. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a schematic diagram of a conventional dual pod. [Diagram 2] FIG. 1 illustrates six axes of motion of a conventional lid. [Diagram 3] FIG. 13 is a diagram showing a partial structure when a conventional lid is fitted to a base. [Figure 4] FIG. 2 is a plan view of the dual pod of the present invention. [Diagram 5] FIG. 5 is a cross-sectional view taken along line AA of FIG. 4. [Figure 6] FIG. 1 illustrates the six axes of motion of the lid of the present invention. [Figure 7] FIG. 2 is another partial cross-sectional structural view of the dual pod of the present invention. [Figure 8] FIG. 2 is a diagram showing a partial structure of a lid according to the present invention. [Figure 9] FIG. 6 is a partially enlarged view of FIG. [Figure 10] FIG. 5 is a cross-sectional view taken along line BB in FIG. 4. [Figure 11] 13 is another partially enlarged view showing the relationship of the first guide rib and the second guide rib to the notch. FIG. [Figure 12A] 6 is a schematic diagram showing a notch contact state of a first guide rib and a second guide rib. [Figure 12B] 6 is a schematic diagram showing a notch contact state of a first guide rib and a second guide rib. [Figure 13] 1 is a schematic diagram of a dual pod according to another embodiment of the present invention. [Figure 14] 1 is a schematic diagram of a dual pod according to another embodiment of the present invention. [Figure 15] 1 is a schematic diagram of a dual pod according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In order to better explain the present invention, specific examples and embodiments will be described with reference to the accompanying drawings below. However, it should be understood that the subject matter of the present application can be specifically implemented in various different forms, and the configurations covered or provided by the subject matter of the present application are not limited to any exemplary specific embodiments disclosed in the description and specification of the present application, and the exemplary specific embodiments are merely illustrative. Similarly, the present invention aims to provide a reasonable and wide scope of the subject matter to which it is applied or covered. Furthermore, the accompanying drawings and the examples of the present invention are not drawn to scale and are not intended to correspond to actual relative dimensions.

[0022] For the purpose of achieving consistency and better understanding, the illustrated drawings denote identical features with symbols and reference numbers (although in some examples they are not so labeled). However, features in different embodiments may differ in other respects and should not be narrowly limited to those depicted in the drawings. Terms such as "first" and "second" in this specification and the drawings are used to distinguish different objects and should not be construed as describing any particular order.

[0023] FIG. 4 is a plan view of the dual pod (3) of the present invention. FIG. 5 is a cross-sectional view of the dual pod (3) taken along line AA in FIG. 4, where line AA is the centerline of the dual pod (3) along the X-axis. The dual pod (3) includes an outer pod (30) and an inner pod (40). The outer pod (30) has, as its main components, a housing (31) and a door (32), which are joined together to define a space for receiving the inner pod (40). The housing (31) has, as its basic components, a ceiling or ceiling (311) and a wall (312) extending downward from the ceiling (311). Each of the housing (31) and the door (32) includes many elements. For example, the housing 31 has a pair of handles provided on the outside, and the door (32) has an operable latch assembly, the details of which are omitted in this application. The housing (31) and door (32) elements may be formed by molding to form a moldable material into a particular configuration.

[0024] The inner pod (40) has as its main components a lid (41) and a base (42) that are joined together to define a space for receiving a reticle (not shown in the drawing), e.g., an EUV reticle. Each of the lid (41) and the base (42) has a number of elements. For example, the top portion of the lid (41) is provided with a gas exchange means and a filtering means, as well as a number of contact portions that can form a mating relationship with the inside of the housing (31), and the inside of the base (42) is provided with a number of support members that support and restrain the reticle.

[0025] To accommodate the inner pod (40) in the outer pod (30), the inner pod (40) is first placed on a number of support members (33), such as commonly known kinematic coupling pins, provided on the inside of the door (32), and then the housing (31) is placed to cover the door (32). In this case, the hold-down mechanisms provided on the inside of the housing (31) abut against corresponding contact portions of the lid (41) of the inner pod (40), so that the Z-axis, B-axis, and X-axis of the inner pod (40) are restrained as shown in FIG.

[0026] Referring to FIG. 5, which shows the cross-sectional structure of the dual pod (3) taken along the line AA in FIG. 4, a pair of guide mechanisms (313) are provided inside the housing (31) of the present invention. The guide mechanisms (313) are configured to abut against the flange (i.e., handle 411) of the lid (41) of the inner pod (40) when the housing (31) covers the door (32) to limit the horizontal and rotational movement of the lid (41) between the housing (31) and the door (32), and more specifically, to limit the movement and rotation around the X-axis and Y-axis shown in FIG. 6, for example. In the present invention, the abutment position of the guide mechanisms (313) against the flange is not determined. For example, such a position can be adjusted according to the requirements of the mechanism, and the guide mechanisms (313) can abut against the center or two ends of the handle (411) in FIG. 13. The guide mechanism (313) is disposed substantially where the ceiling (311) and the inner wall (312) join, and the guide mechanism protrudes inwardly from the housing (31). More specifically, one portion of the guide mechanism (313) is coupled to the ceiling (311) of the housing (31), and another portion of the guide mechanism (313) is coupled to the inner wall (312) of the housing (31).

[0027] In this embodiment, a pair of guide mechanisms (313) are provided inside the housing (31) corresponding to the line AA. In other possible embodiments, the guide mechanism (313) is provided on the ceiling (311) or the inner wall (312). The guide mechanism (313) and the housing (31) are made of different materials, and the guide mechanism (313) may be made of a relatively soft and flexible material with high elasticity or flexibility, and the material forming the guide mechanism (313) is plastic, rubber, silicone, metal, or a combination thereof, so that the guide mechanism (313) can be deformed under external force. The guide mechanism (313) can be formed as a single piece with the housing (31) by molding, or can be heterogeneously joined with the housing (31) by an embedded injection molding method.

[0028] Additionally, the guide mechanism 313 is configured to engage with an engagement portion (described below) formed on the lid 41 of the inner pod 40, particularly when the housing 31 is over the door 32. The engagement between the engagement portion and the guide mechanism 313 makes the cover 41 less susceptible to horizontal movement or rotation when subjected to external forces.

[0029] FIG. 6 shows the directional constraint state of the inner pod (40), especially the lid (41). Compared with FIG. 2 (where only Z-axis, A-axis and B-axis are restricted in the conventional configuration), the effect is obtained for all six axes in FIG. 6. The pair of guide mechanisms (313) complement the constraints not shown in FIG. 2, i.e., X-axis, Y-axis and C-axis in FIG. 2, so that almost any direction of the lid (41) is constrained, thus effectively preventing the lid (41) from sliding relative to the base (42). Due to such a structural design, the guide mechanism (313) can provide a constraint even in the Z-axis direction.

[0030] FIG. 7 shows another partial cross-sectional structure of the dual pod (3) of the present invention. FIG. 8 shows a partial structure of the lid (41). FIG. 9 shows a partial enlarged view of FIG. 5. The lid (41) of the inner pod (40) of the present invention is configured to have a pair of engagement parts. Specifically, as shown in FIG. 5, the two opposite sides of the cover (41) are provided with a pair of handles (411), which extend outward from the two opposite sides. The handles (411) are designed to be in a mating relationship with the lid opening means of the machine. The plan view of the lid (41) in FIG. 13 further shows the pair of handles (411), each of which has two ends. In this embodiment, the engagement parts are notches (412) formed in the handles (411), as shown in FIG. 8. The notch (412) has a varying width, the maximum width being the notch edge width (W). As shown in Figure 8, the edge (413) of the handle (411) and the other edge (413) appear discontinuous due to the formed notch (412). In other embodiments, the portion of the notch (412) is not limited to a central location of the handle (411).

[0031] As shown in Fig. 7, in this embodiment, the guide mechanism (313) includes a first guide rib (313A) and a second guide rib (313B), which abuts against the handle (411) of the lid (41) by engaging with the notch (412). The first guide rib (313A) and the second guide rib (313B) are mutually symmetrical structures. The first guide rib (313A) and the second guide rib (313B) are shaped to have a mating relationship with the notch (412), so that the first guide rib (313A) and the second guide rib (313B) can abut against the edge of the notch (412) simultaneously. Furthermore, the first guide rib (313A) and the second guide rib (313B) elastically deform in unison as the width (opening) of the notch (412) into which they are inserted changes, so that the first guide rib (313A) and the second guide rib (313B) fit into and are restrained within the notch (412).

[0032] Referring to FIG. 9, the first guide rib (313A) has an inclined surface (51), which extends substantially from the ceiling (311) toward the inner wall (312). When the first guide rib (313A) is in contact with the edge of the notch (412), the first guide rib (313A) exerts a force in the -Z direction (opposite to the +Z direction) and the -Y direction (opposite to the +Y direction), thereby moving the lid (41) toward the center of the base (42). The inclined surface (51) and the top surface of the lid (41) form an included angle ranging from 0.01° to 89.9°. Similarly, FIG. 9 does not show the second guide rib (313B), but the second guide rib (313B) also has an inclined surface (51) that matches the inclined surface of the first guide rib (313A). FIG. 9 further shows that the first guide rib (313A) of the guide mechanism (313) has a guide portion (61) and a connecting portion (62). The guide portion (61) is a tooth-like structure, and the connecting portion (62) is for connecting to the inside of the housing (31). The guide portion (61) receives a force when it abuts against the notch (412), and can elastically deform accordingly, thereby guiding the guide portion (61) through the notch (412) and restraining it at the notch. Preferably, the mechanical thickness of the guide portion (61) is small to exhibit elastic and flexible properties, and the mechanical thickness of the connecting portion (62) is large to obtain good mechanical strength. A gap (52) is formed between the guide portion (61) and the inner wall (312) to provide a stroke distance (i.e., tolerance) between the guide portion (61) and the inside of the outer pod (30) (i.e., the inner wall 312), and therefore a buffer in the horizontal direction when the guide portion (61) deforms. For example, the gap (52) provides a tolerance when the guide portion (61) moves toward the +Y direction to restrain the lid (41). In other possible embodiments, the gap (52) may also be filled with other materials or mechanisms to achieve the same function.

[0033] Figure 10 shows a cross-sectional structure taken along line BB in Figure 4, and Figure 10 clearly shows the relationship between one of the pair of guide mechanisms (313) and the handle (411). Figure 11 is another partially enlarged view, and Figure 11 clearly shows the relationship of the first guide rib (313A) and the second guide rib (313B) to the notch (412). Figures 12A and 12B show schematic diagrams of the contact state between the first guide rib (313A) and the second guide rib (313B) and the notch (412). When the first guide rib (313A) and the second guide rib (313B) are not engaged with the notch (412), a first guide width (W') is generated between the first guide rib (313A) and the second guide rib (313B), and the first guide width (W') is smaller than the notch edge width (W). When the notch (412) and the first guide rib (313A) and the second guide rib (313B) are engaged with each other, the first guide rib (313A) and the second guide rib (313B) move toward one end of the notch (412), and the first guide rib (313A) and the second guide rib (313B) approach each other to generate a second guide width (W") smaller than the first guide width (W'). The first guide width (W') and the second guide width (W") are primarily a relationship between the two guide portions (61), and the connecting portion (62) basically exhibits relatively insufficient elasticity or flexibility, and such connecting portion cannot easily change the width between the two guide portions. When the first guide rib (313A) and the second guide rib (313B) move away from the notch (412), the first guide rib (313A) and the second guide rib (313B) return from their close proximity to each other to a predetermined state, i.e., a first guide width (W') is generated between the two guide portions (61).

[0034] Figures 13, 14 and 15 show a dual pod according to another embodiment of the present invention, in which the housing is removed and not shown. The difference from the above-mentioned embodiment is that a pair of guide mechanisms (313') in this embodiment are provided on the inner top portion or upwardly facing surface of the door (32) and are configured to protrude upwards, so that when the inner pod (40) is placed on the door (32), the guide mechanisms (313') abut against a flange of the lid (41) of the inner pod (40), thereby limiting the rotation of the lid (41) in the C-axis direction.

[0035] In this embodiment, the guide mechanism 313' also has a ramp 51' that extends upward from the inner top portion or upwardly facing surface of the door 32 to easily contact the flange structure, i.e., handle 411, of the lid 41. Once the edge of the lid 41 contacts the ramp 51', the force provided by the ramp 51' restricts the lid 41 in the -Z direction (opposite to the +Z direction), the Y axis direction, and the C axis direction. In this case, the +Z direction of the lid 41 can still be restricted by the hold-down mechanism of the housing 31. Similarly, the handle 411 may be formed to have an engagement portion that mates with the guide mechanism 313', such as the notch 412 described above. The guide portion, i.e., end portion, of the guide mechanism (313') may have a first guide rib (313A') and a second guide rib (313B') having an interacting relationship with the notch (412) as described above with reference to Figures 11 and 12. The overall structure and shape of the guide mechanism (313') may be suitably configured such that a gap is likewise maintained between the first guide rib (313A') and the inside of the housing (31) and between the second guide rib (313B') and the inside of the housing (31), which in this case serves as a buffer space.

[0036] In conclusion, the present invention provides a dual pod including at least an outer pod having a pair of guide mechanisms provided inside, the guide mechanisms being specifically designed to abut against one side or flange structure of the lid of the inner pod, thus, during storage or transportation of the outer pod, the horizontal movement (i.e. along the X-axis and Y-axis) and rotational movement (i.e. around the C-axis) of the lid can be further restricted, thus helping to reduce friction between the lid and the base of the inner pod and thus the generation of contaminant particles.

[0037] It should be understood, however, that the particular embodiments of the present invention are for illustrative purposes and that various modifications can be made without departing from the scope and spirit of the present invention as set forth in the appended claims. Moreover, such modifications are within the scope of the present invention as set forth in the appended claims. Accordingly, the particular embodiments provided in the specification of this disclosure should not be construed as limiting the present invention, the true scope and spirit of the present invention being set forth in the appended claims. [Explanation of symbols]

[0038] 1,3 Dual Pod 10,30 Outer pod 20,40 Inner pod 31 Housing 32 Doors 33 Support member 42 Base 51 Slope 52 Gap 311 Ceiling 312 Wall 313 Guiding mechanism 411 Handle 412 Notch

Claims

1. A dual pod, an inner pod, the inner pod being provided with at least one engagement portion on a relatively outer side thereof; A dual pod comprising an outer pod defining a storage space for receiving the inner pod, at least one guide mechanism being provided relatively inwardly of the outer pod, the guide mechanism being guided by and restrained at the engagement portion so as to limit offset movement of the inner pod within the outer pod.

2. The dual pod of claim 1 , wherein the guide mechanism includes a guide portion and a connecting portion connected to the guide portion, the connecting portion being connected to an inside of the outer pod, and the guide portion abutting the engagement portion of the inner pod while being spaced from the inside of the outer pod.

3. 3. The dual pod of claim 2, wherein the guide portion is flexible, the engagement portion is a notch, and the guide portion deforms in a corresponding relationship according to a force applied to the notch and is accordingly guided by and restrained at the notch.

4. The dual pod of claim 2, wherein a gap having a stroke distance is provided between the guide portion and the inside of the outer pod, the gap serving as a tolerance to allow the guide portion to flexibly abut against the engaging portion of the inner pod.

5. 4. The dual pod of claim 3, wherein the guide portion comprises a pair of first and second guide ribs that elastically deform in unison as the opening degree of the notch into which the guide ribs are inserted changes, so that the first and second guide ribs are fitted and restrained within the notch.

6. The dual pod of claim 3 , wherein the notch has a notch edge width, and the width of the guide portion is less than the notch edge width.

7. the inner pod having a base and a lid joined together to define a receiving space for receiving a reticle; the outer pod having a door and a housing joined together to define the storage space; 2. The dual pod of claim 1, wherein the vertical direction of the lid is restrained by the guide mechanism to prevent the inner pod from deflecting offset relative to an axis due to an external force, and the horizontal direction of the lid is restrained by the guide mechanism.

8. 8. The dual pod of claim 7, wherein each of two opposing surfaces of the lid is provided with a flange, the engagement portion is provided on the outside of the flange, the guide mechanism is positioned to match the flange, and the guide mechanism is guided by the engagement portion and restrained at the engagement portion.

9. 8. The dual pod of claim 7, wherein a flange is provided on each of two opposing surfaces of the lid, the engagement portion is provided on the outside of the flange, and the guide mechanism has an inclined surface that abuts against the flange, the inclined surface extending from a top portion of the housing toward an inner wall of the housing so that the vertical direction and at least the horizontal direction of the flange are restrained by the inclined surface.

10. The dual pod of claim 9 , wherein the angled surface and the top surface of the lid form an included angle in the range of 0.01° to 89.9°.

11. A dual pod as described in claim 7, wherein a flange is provided on each of two opposing surfaces of the lid, the engagement portion is provided on the outside of the flange, and the guide mechanism has an inclined surface that abuts against the flange, the inclined surface being formed to protrude upward from the inner top portion of the door, such that the vertical direction and at least the horizontal direction of the flange are restrained by the inclined surface.

12. 8. The dual pod of claim 7, wherein each of the two opposing surfaces of the lid is provided with a flange, the engagement portion is provided on the outside of the flange, and the guide mechanism has at least two guide ribs arranged in parallel, the two guide ribs being formed to protrude upward from the inner top portion of the door, and the two guide ribs resiliently abut against the inside of the engagement portion to achieve the restraint.

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