JP2018509767A - Improved spring cushion for film frame shippers - Google Patents

Abstract

A film frame shipper that provides enhanced prevention of film frame jumps within the film frame shipper. In addition, this structure that prevents jumping further improves the alignment of the film frame when mounted on the sipper. Furthermore, in certain embodiments, the above structure allows for a less marginal fit between the thickness of the film frame and the positioning slot, thereby allowing play between the film frame and the positioning slot, and The accompanying particle generation is reduced. [Selection] Figure 8B

Description

This application claims the benefit of US Provisional Patent Application No. 62 / 133,131, filed Mar. 13, 2015, the disclosure of which is hereby incorporated by reference in its entirety.

  The present disclosure is generally directed to wafer shippers, and more specifically to film frame or tape frame shippers.

  Film frames or tape frames generally consist of a stainless steel frame with a film extending between the frames. The film has an adhesive on one side thereof. A circular semiconductor wafer is typically placed on this film after processing. After being placed on the film, the semiconductor wafer can be divided into individual pieces (e.g., chips) and transported or stored for further processing. Larger and thinner wafers are being used in the semiconductor processing industry, but these wafers are becoming more fragile, making them difficult to handle during processing, transport, and storage. ing. Thus, conventional film frame wafer carriers can be improved for handling film frames with such larger and thinner wafers.

  Film frame shippers are widely used in the semiconductor manufacturing industry to transport film frames. A wide variety of film frame shippers provide a safe and efficient way to transport and store up to 25 wafers or singulated dies mounted on the film frame. A replaceable top cover cushion allows reuse of the sipper. Film frame shippers are available for film frames used to transport 300 mm, 200 mm, and 150 mm diameter wafers.

  It is known that film frames mounted in conventional film frame shippers “jump” when an impact occurs. For example, when a film frame shipper falls with its corners down, the shape of the polymer may be instantly deformed because the film frame in it falls considerably heavy. In addition, due to the inertial force of the film frame included in the film frame shipper, the film frame jumps out of its predetermined registration slot and comes into contact with the adjacent film frame and the wafer or sipper on the adjacent film frame. Damage to the wafer can be caused.

  Referring to FIG. 5, a known film frame 40 is depicted. The film frame 40 includes a frame 42 that defines an outer edge 44. An adhesive film 46 is stretched over the frame, and a wafer 48 is bonded to the adhesive film 46. If the film frame pops out when an impact occurs, the wafer on the popped out film frame may come into contact with another wafer, the frame 42, or a portion of the sipper, causing damage to the wafer.

  There is a need for a film frame shipper that is more reliable in holding a film frame at a predetermined positioning position when an impact occurs.

  Various embodiments of the present disclosure provide enhanced prevention against film frame jumps within the film frame shipper. In addition, this structure that prevents jumping further improves the alignment of the film frame when mounted on the sipper. Further, in certain embodiments, the above structure allows for a less marginal fit between the thickness of the film frame and the positioning slot, thereby allowing play between the film frame and the positioning slot. ), And the accompanying particle generation.

  Each wafer is supported on a metal or polymer wafer support ring or wafer support frame. The wafer support ring is received in and held by a spring cushion located at the top and / or bottom of the film frame shipper. The spring cushion applies a radial force to the film frame to secure each film frame in the corresponding positioning slot, thereby reducing the movement of the film frame in the positioning slot and during transportation. Reduce particle migration or generation. In some embodiments, the spring cushion may be removable and / or replaceable and may include snap features that facilitate the connection between the spring cushion and the sipper. Additional features of the film frame shipper include a positive snap latch to ensure sipper closure, a non-protruding latch and stackable design to reduce storage space and transportation costs, and during cleaning Chamfered corners and inclined sides to reduce wafer entrapment. As the film frame shipper, an ESD-compatible material can be used. Radio identification (RFID) and laser marking options are also available.

FIG. 3 is an assembly diagram of a film frame shipper and a film frame therein in an embodiment of the present disclosure. It is the schematic of the film frame mounted in the receptacle of the film frame shipper of FIG. It is a perspective view of the film frame receptacle in which the film frame was mounted. It is a perspective view of the film frame shipper of FIG. It is sectional drawing of the film frame shipper of FIG. It is a cross-sectional perspective view of the film frame shipper with the film frame of FIG. It is a top view of the film frame of a prior art. FIG. 6 is a perspective view of a spring frame cushion in an embodiment of the present disclosure. FIG. 7 is an enlarged perspective view of the spring frame cushion of FIG. 6 in an embodiment of the present disclosure. FIG. 6 is a perspective view of a spring frame cushion in an embodiment of the present disclosure. FIG. 8 is a cross-sectional view of the spring frame of FIGS. 6 and 7. FIG. 2 is a perspective view of the interior of the top cover of the film frame shipper of FIG. 1, showing a mounting post for receiving a spring frame. FIG. 8B is a view of FIG. 8A with the spring frame received. It is a section perspective view of a film frame shipper in one embodiment of this indication. FIG. 10 is an enlarged cross-sectional perspective view of the side comb structure of FIG. 9 in an embodiment of the present disclosure. FIG. 10 is an enlarged cross-sectional perspective view of the bottom comb structure of FIG. 9 in an embodiment of the present disclosure. FIG. 3 is a schematic cross-sectional view of a film frame shipper having an upper spring frame cushion and a lower spring frame cushion in an embodiment of the present disclosure. 1 is a schematic cross-sectional view of a film frame shipper having an upper spring frame cushion and a pair of lower spring frame cushions in an embodiment of the present disclosure.

  1-4 illustrate a film frame sipper 20 in one embodiment of the present disclosure. The film frame shipper 20 includes a receptacle 22 and a cover 24 that forms a closure above the receptacle portion and defines an interior space 26 for storing a plurality of film frames 28. The receptacle 22 includes a side 32 that may include a guide 34 for guiding the film frame 28 into the receptacle 22 (FIG. 2). A spring frame cushion 36 is coupled to at least one of the receptacle 22 and the cover 24. In one embodiment, the frame cushion 36 is removably attached to the receptacle 22 or the grooved rail 38 of the cover 24. As shown, the film frame 28 is oriented in direction A into the interior space 26 of the receptacle 22, and then the cover 24 moves in the same direction A and couples with the receptacle 22.

  With reference to FIGS. 6-8, an example of a spring frame 36 in an embodiment of the present disclosure is depicted. The spring frame 36 is specifically referred to as a spring frame 36a (FIG. 6) and a spring frame 36b (FIG. 7), and is generally or collectively referred to as a spring frame (s) 36. The spring frame 36 includes opposed rails or side walls 52, 54 that extend in the front / rear direction 56 and connect to the end walls 55, 57 to form a rectangular frame structure 59. This rail supports a main cushion portion 58 in which a plurality of spring cushion elements 60 are interposed between the rails. Each spring cushion element 60 defines a positioning slot 62. Each of the plurality of positioning slots 62 extends in a lateral direction 64 that is perpendicular to the front / rear direction 56, and the positioning slot 64 captures the outer edge 44 of the film frame 40, and the film frame in the front / rear direction 56. It is adapted to limit 40 movements.

  In various embodiments, the first comb structure 72 includes a plurality of first comb protrusions 74 that extend in a vertical direction 76 from the opposed first sidewalls 52 of the spring frame cushion 36. (The vertical direction 76 is perpendicular to the front / rear direction 56 and perpendicular to the lateral direction 64.) The plurality of first comb-shaped protrusions 74 define a plurality of first comb-shaped gaps 78. Are separated from each other. Each protrusion has a straight portion 79 and a tapered portion 80. Adjacent first comb projections of the plurality of first comb projections 74 are adapted to engage and receive the outer edge of the film frame 40, each of the plurality of first comb gaps 78 being A plurality of comb-shaped gaps 78 are defined between adjacent protrusions of the first comb-shaped protrusions 74 of the first comb-shaped structure 72, and capture the outer edge 44 of the film frame 40 in the front / rear direction 56. It is adapted to limit the movement of the outer edge 44. In addition, each of the plurality of positioning slots 62 is aligned with the corresponding gap among the plurality of first comb gaps 78 in the lateral direction 64.

  In some embodiments, the second comb structure 82 includes a plurality of second comb protrusions 84 that extend in a vertical direction 76 from the opposed second sidewalls 54 of the spring frame cushion 36. The plurality of second comb-shaped protrusions 84 are separated from each other so as to define a plurality of second comb-shaped gaps 88. Adjacent protrusions of the plurality of second comb-shaped protrusions 84 are adapted to engage and receive the outer edge 44 of the film frame 40, and each of the plurality of second comb-shaped gaps 88 is connected to the second comb-shaped gap 88. The plurality of second comb-shaped gaps 88 are defined between adjacent protrusions of the plurality of second comb-shaped protrusions 84 of the shaped structure 82, and each of the plurality of second comb-shaped gaps 88 captures the outer edge portion 44 of the film frame 40, and It is adapted to limit the movement of the outer edge 44 in the direction 56. In addition, each of the plurality of positioning slots 62 is aligned with the corresponding gap among the plurality of second comb-shaped gaps 88 in the lateral direction 64.

  In various embodiments, as best shown in FIG. 6A, at least a portion of the plurality of first comb projections 74 and / or the plurality of second comb projections 84 are respectively proximal end 92 and A tapered shape 96 is defined that includes the distal end 94 and protrudes in the lateral direction 64. The tapered shape 96 may be symmetric around the protrusion axis 98 (FIG. 6A) extending in the vertical direction 76 and is inclined toward the protrusion axis 98 from the proximal end 92 to the distal end 94. ing. In one embodiment, at least a portion of the tapered shape 96 is arcuate (not shown).

  In one embodiment, the main cushion portion 58 defines a plurality of through slots 102, each of the plurality of through slots 102 (FIG. 7) being adjacent spring cushion elements 60, each having a corresponding positioning slot 62. Located between the spring cushion elements 60 having.

  With reference to FIGS. 8 and 9, the spring frame cushion 36 is integrated by an interference fit with a tapered post 104 that is integral with and extends from the inner surface 106 of the cover 24. Attached to the cover 24. The post forms a slot 105 such that the rail is tightened within the slot 105 sufficient to frictionally secure the spring frame cushion to the top cover. Top cover 24 and receptacle 22 have ribs 107 that define slots 108 for receiving and restraining the film frame.

  With reference to FIGS. 9-11, another comb-like structure in an embodiment of the present disclosure is disclosed. In one embodiment, on the base 112 of the receptacle 22, at least one base comb-like structure 110 that extends in a vertical direction 76 from the base of the receptacle 22 to the interior space 26. A base comb structure 110 including 114 is disposed. The plurality of base comb-shaped protrusions 114 are spaced from each other so as to define a plurality of base comb-shaped gaps 118. Adjacent protrusions of the plurality of base comb-shaped protrusions 114 are adapted to engage and receive the outer edge 44 of the film frame 40, and each of the plurality of base comb-shaped gaps 118 includes a base comb-like structure. 110 of the plurality of base comb protrusions 114 are defined between adjacent protrusions.

  The plurality of base comb-shaped gaps 118 are adapted to capture the outer edge 44 of the film frame 40 and limit movement of the outer edge 44 in the front / rear direction 56. Further, each of the plurality of positioning slots 62 of the spring frame cushion 36 is planarly aligned with the corresponding gap among the plurality of base comb-like gaps 118. That is, the center of each of the base comb-shaped gaps 118 is on a plane perpendicular to the front / rear direction 56, and the center of one of the positioning slots 62 is also on this plane. In one embodiment, at least a portion of the plurality of base comb protrusions 114 includes the tapered shape depicted in FIG. 6A.

  In one embodiment, the positioning rail 116 protrudes from the base and extends in the front / rear direction 56. This positioning rail defines a rail height 112 in the vertical direction 76 above the base 112 of the receptacle 22. The proximal tip 124 of each of the plurality of base comb gaps 118 (ie, the “bottom” of the gap 118) defines a gap offset 126 from the base 112 that is below the rail height 112 (FIG. 11) and is relative to the base 112. The distal tip 128 of each of the plurality of base comb protrusions 114 defines a protrusion height 132 that exceeds the rail height 122.

  Functionally, since the rail height 122 from the base 112 exceeds the gap offset 126, the film frame 40 inserted into the base comb 112 will rest on the positioning rail 116. This may release the base comb 110 from some sort of stress and provide a more accurate positioning of the film frame 40 within the film frame shipper 20.

  In some embodiments, the side 32 of the receptacle 22 has at least one side comb 140 that extends in a vertical direction 76 into the interior space 26 and has a plurality of side combs. Side comb-like structures 140 including 142 are arranged. The plurality of side comb-like protrusions 142 are spaced apart from each other to define a plurality of side comb-like gaps 148. Adjacent protrusions of the plurality of side comb protrusions 142 are adapted to engage and receive the outer edge 44 of the film frame 40, each of the plurality of side comb gaps being a side comb. Defined between adjacent side comb-like projections of the shaped structure.

  The plurality of side comb-like gaps are adapted to capture the outer edge 44 of the film frame 40 and limit movement of the outer edge 44 in the front / rear direction 56. In addition, each of the plurality of positioning slots 62 of the spring frame cushion 36 is planarly aligned with the corresponding gap among the plurality of side comb-like gaps 148. In one embodiment, at least a portion of the plurality of side comb protrusions 142 includes the tapered shape depicted in FIG. 6A.

  In various embodiments, referring to FIG. 8, each of the plurality of first comb gaps 78 and second comb gaps 88 defines a gap depth 152 having a proximal tip 154. Each of the plurality of first and second comb-shaped protrusions 74, 84 extends from the proximal tip 154 of one adjacent gap among the plurality of first and second comb-shaped gaps 78, 88. / Defines a protrusion height 156 in the vertical direction 76 to the distal tip 158 of the adjacent one of the second comb protrusions 74, 84. Each of the plurality of positioning slots 62 defines a slot depth 162 in the vertical direction 76 with respect to the upward surface of the main cushion portion 58.

  In various embodiments, the ratio of the protrusion height 152 to the slot depth 162 is in the range of 1.5 to 5. In some embodiments, this ratio is in the range of 2 to 4. In some embodiments, this ratio is in the range of 2.5 to 3.5. (In this document, the range expressed as “inclusive” includes both end values of the described range.) In all of the above embodiments, the first and second comb protrusions 74, 84 is higher than the slot depth 162.

  In terms of functionality, the fact that the first and second comb-shaped protrusions 74 and 84 are higher than the slot depth 162 helps to prevent or disable the “jump” of the film frame 40 when an impact occurs. In the figures presented in this document, the undeformed spring frame cushion 36 is depicted. When the film frame 40 is mounted, the main cushion portion 58 deforms so that the bottom of the slot 166 is flush with the proximal tip 154. Therefore, even if the film frame 40 “jumps” in the positioning slot 62, the height of the protrusions 78 and 88 restrains the outer edge 44 of the film frame 40, and the film frame 40 is placed in the positioning slot 62. Redirected back.

  Referring again to FIG. 6A, in one embodiment, at least a portion of the plurality of first and second comb gaps 78, 88 each define a minimum gap dimension 172 in the anterior / posterior direction 56. The minimum gap dimension 172 can be sized for a close slip fit with the film frame. In some embodiments, the minimum gap dimension 172 is in the range of 0.05 inches to 0.085 inches. In some embodiments, the minimum gap dimension 172 is in the range of 0.055 inches to 0.075 inches. In some embodiments, the minimum gap dimension 172 is in the range of 0.055 inches to 0.065 inches.

  In terms of functionality, the margin of the minimum gap dimension 172 relative to the outer edge 44 of the film frame 40 becomes tighter, thereby holding the film frame 40 tighter, thereby moving the film frame 40 in the forward / rearward direction 56. Is reduced. This acts to reduce particle generation. On the other hand, the slot 62 can remain large in size to accommodate for ease of alignment when mounted and realignment when an impact occurs.

  In various embodiments, the spring frame cushion 36 is removable from the film frame shipper 20 by being attached to the grooved rail 38 by press fit.

  Referring to FIG. 12, the first spring frame frame 36 is disposed on the cover, and the second spring frame cushion 36 is disposed on the receptacle.

  Referring to FIG. 13, a third spring frame cushion 36 is disposed on the receptacle.

In various embodiments, referring again to FIGS. 6 and 7, the spring frame cushion 32 includes a continuous frame 182. The continuous frame 182 includes four walls that define four corners 184. In the spring frame cushion 36b, the first and second comb structures 72 and 82 include protrusions 186 that extend around the four corners 184.

Claims (28)

A receptacle,
A cover forming a closure above the receptacle portion to define an interior space;
A spring frame cushion connected to at least one of the receptacle and the cover, wherein the spring frame includes opposing side walls extending in a front / rear direction and supporting a main cushion portion; A main cushion portion defines a plurality of positioning slots, each of the plurality of positioning slots extending in a lateral direction perpendicular to the front / rear direction and capturing an outer edge of the film frame A spring frame cushion adapted to limit movement of the film frame in the front / rear direction;
A plurality of first comb-like structures including a plurality of first comb-like protrusions extending vertically from a first one of the opposed side walls of the spring frame cushion, the plurality of first comb-like structures First combs spaced apart from each other to define a plurality of first comb-shaped gaps, wherein the vertical direction is perpendicular to the front / rear direction and perpendicular to the lateral direction A film frame sipper comprising a structure,
Adjacent protrusions of the plurality of first comb-shaped protrusions are adapted to engage and receive the outer edge of the film frame, and each of the plurality of first comb-shaped gaps is the first comb-shaped protrusion. The first comb-like projections of the structure are defined between adjacent projections, and each of the plurality of first comb-like gaps captures the outer edge portion of the film frame and moves in the front / rear direction. Adapted to limit movement of the outer edge,
Each of the plurality of positioning slots is aligned with a corresponding gap among the plurality of first comb gaps in the lateral direction. A second comb-like structure including a plurality of second comb-shaped protrusions extending in the vertical direction from a second one of the opposed side walls of the spring frame cushion, wherein the plurality of second combs The second protrusions are spaced apart from one another to define a plurality of second comb-like gaps;
Adjacent second comb-like projections of the plurality of second comb-like projections are adapted to engage and receive the outer edge of the film frame, and one of the plurality of second comb-like gaps A second comb-shaped gap is defined between the adjacent second comb-shaped protrusions of the second comb-shaped structure, and the second comb-shaped gap captures the outer edge of the film frame, and Adapted to limit the movement of the outer edge in the front / rear direction,
2. The film frame shipper according to claim 1, wherein each of the plurality of positioning slots is aligned with a corresponding one of the plurality of second comb-shaped gaps in the lateral direction.   The film frame shipper of claim 1, wherein the primary cushion portion defines a plurality of through slots, each of the plurality of through slots being disposed between adjacent positioning slots of the plurality of positioning slots. . A plurality of base comb-like protrusions disposed on the base of the receptacle, the base comb-like protrusions extending in the vertical direction from the base of the receptacle to the internal space; A base comb structure comprising a plurality of base comb protrusions spaced apart from each other to define a plurality of base comb gaps;
Adjacent protrusions of the plurality of base comb protrusions are adapted to engage and receive the outer edge of the film frame, and each of the plurality of base comb gaps includes the plurality of base comb protrusions. A plurality of base comb-like gaps adapted to capture the outer edge of the film frame and limit movement of the outer edge in the front / rear direction. And
4. Each of the plurality of positioning slots of the spring frame cushion is planarly aligned with a corresponding gap of the plurality of base comb-like gaps. Film frame shipper.   A plurality of base rails that project from the base and extend in the front / rear direction, the positioning rails defining a rail height in the vertical direction over the base of the receptacle; A proximal tip of each of the comb-like gaps defines a gap offset from the base below the rail height, and a distal tip of each of the plurality of base comb-like projections relative to the base reduces the rail height. The film frame shipper of claim 4, wherein the film frame sipper defines a protrusion height that is greater. At least one side comb-like structure disposed on a side of the receptacle, the plurality of side comb-like protrusions extending in the vertical direction into the internal space, and having a plurality of sides A plurality of side comb-like protrusions spaced apart from each other to define a partial comb-like gap, comprising a side comb-like structure,
Adjacent protrusions of the plurality of side comb-like protrusions are adapted to engage and receive the outer edge of the film frame, and each of the plurality of side comb-like gaps includes the plurality of side parts. Composed between adjacent protrusions of the comb-shaped protrusion, each of the plurality of side comb-shaped gaps captures the outer edge of the film frame and moves the outer edge in the front / rear direction. Adapted to limit,
5. The film frame shipper according to claim 4, wherein each of the plurality of positioning slots of the spring frame cushion is planarly aligned with a corresponding one of the plurality of side comb-like gaps.   At least a portion of the plurality of first comb-shaped protrusions, the plurality of second comb-shaped protrusions, the plurality of base comb-shaped protrusions, and / or the plurality of side comb-shaped protrusions are respectively a proximal end and a distal end. An end portion and defining a laterally projecting taper shape, the taper shape being symmetrical about a projection axis extending in the vertical direction, from the proximal end to the distal end The film frame shipper according to claim 6, wherein the film frame shipper is inclined toward the projection and toward the projection axis.   The film frame shipper of claim 7, wherein at least a portion of the tapered shape is arched. Each of the plurality of first comb-like gaps defines a gap depth having a proximal tip;
Each of the plurality of first comb-shaped protrusions is connected to the adjacent one of the plurality of first comb-shaped protrusions from the proximal tip of the adjacent one of the plurality of first comb-shaped gaps. Defining a vertical projection height to the distal tip,
Each of the plurality of positioning slots defines a slot depth in the vertical direction with respect to an upward surface of the main cushion portion;
The film frame shipper according to claim 7, wherein a ratio of the protrusion height to the slot depth is in a range of 1.5 or more and 5 or less.   The film frame shipper according to claim 9, wherein the ratio is one of a group consisting of a range of 2 to 4 and a range of 2.5 to 3.5.   At least a portion of the plurality of first comb-like gaps, the plurality of second comb-like gaps, the plurality of base-side comb-like gaps, and / or the plurality of side-side comb-like gaps are each in the front / rear direction. The film frame shipper of claim 6, wherein a minimum gap dimension is defined and the minimum gap dimension is dimensioned for a close slip fit with the film frame.   The minimum gap dimension is comprised of a range from 0.05 inch to 0.085 inch, a range from 0.055 inch to 0.075 inch, and a range from 0.055 inch to 0.065 inch. The film frame shipper of claim 11, wherein the film frame shipper is one of a group of gap dimensions.   The film frame shipper of claim 1, wherein the at least one spring frame cushion is removable from the film frame shipper.   14. The film frame shipper of claim 1 or 13, wherein the at least one spring frame cushion includes a first spring frame cushion disposed on the cover and a second spring frame cushion disposed on the receptacle.   The film frame shipper of claim 14, wherein the at least one spring frame cushion comprises a third spring frame cushion disposed on the receptacle.   The film frame shipper of claim 1, comprising at least one film frame disposed therein. A spring frame cushion connected to the film frame shipper,
Opposite sides that extend in a front / rear direction and support a main cushion portion, wherein the main cushion portion defines a plurality of positioning slots, each of the plurality of positioning slots being in the front / Opposite sides extending laterally perpendicular to the rear direction and adapted to capture the outer edge of the film frame and limit the movement of the outer edge in the front / rear direction And
A plurality of first comb protrusions extending vertically from a first one of the opposed sides of the spring frame cushion and spaced apart from one another to define a plurality of first comb gaps A first comb-like structure comprising: a first comb-like structure, wherein the vertical direction is perpendicular to the front / rear direction and perpendicular to the lateral direction;
Adjacent protrusions of the plurality of first comb-shaped protrusions are adapted to engage and receive the outer edge of the film frame, and each of the plurality of first comb-shaped gaps is the first comb-shaped protrusion. The first comb-like projections of the structure are defined between adjacent projections, and each of the plurality of first comb-like gaps captures the outer edge portion of the film frame and moves in the front / rear direction. Adapted to limit movement of the outer edge,
Each of the plurality of positioning slots is aligned with a corresponding one of the plurality of first comb-shaped gaps in the lateral direction. A plurality of second comb projections extending in the vertical direction from a second one of the opposed side walls of the spring frame cushion and spaced apart from each other to define a plurality of second comb gaps. Including a second comb-like structure,
Adjacent protrusions of the plurality of second comb-shaped protrusions are adapted to engage and receive the outer edge of the film frame, and each of the plurality of second comb-shaped gaps is configured to receive the second comb-shaped protrusion. Defined between adjacent protrusions of the plurality of second comb-shaped protrusions of the structure, each of the plurality of second comb-shaped gaps capturing the outer edge of the film frame, and Adapted to limit the movement of the outer edge to
18. The spring frame cushion according to claim 17, wherein each of the plurality of positioning slots is aligned with a corresponding gap among the plurality of second comb-like gaps in the lateral direction.   The spring frame cushion of claim 17, wherein the main cushion portion defines a plurality of through slots, each of the plurality of through slots being disposed between adjacent positioning slots of the plurality of positioning slots. .   At least a portion of the plurality of first comb-shaped protrusions each include a proximal end and a distal end, and define a laterally projecting tapered shape, the tapered shape extending in the vertical direction. The spring frame cushion of claim 17, wherein the spring frame cushion is symmetrical about an extending protrusion axis and is inclined from the proximal end to the distal end toward the protrusion axis.   21. The spring frame cushion of claim 20, wherein at least a portion of the tapered shape is arched. Each of the plurality of first comb-like gaps defines a gap depth having a proximal tip;
Each of the plurality of first comb-shaped protrusions is connected to the adjacent one of the plurality of first comb-shaped protrusions from the proximal tip of the adjacent one of the plurality of first comb-shaped gaps. Defining a vertical projection height to the distal tip,
Each of the plurality of positioning slots defines a slot depth in the vertical direction with respect to an upward surface of the main cushion portion;
21. The spring frame cushion according to claim 20, wherein a ratio of the protrusion height to the slot depth is in a range of 1.5 or more and 5 or less.   The spring frame cushion according to claim 25, wherein the ratio is one of a group consisting of a range of 2 to 4 and a range of 2.5 to 3.5.   At least a portion of the plurality of first comb-shaped gaps each define a minimum gap dimension in the front / rear direction, and the minimum gap dimension is sized for a close slip fit with the film frame. The spring frame cushion according to claim 17.   The minimum gap dimension is comprised of a range from 0.05 inch to 0.085 inch, a range from 0.055 inch to 0.075 inch, and a range from 0.055 inch to 0.065 inch. 25. The spring frame cushion of claim 24, wherein the spring frame cushion is one of a group of gap dimensions.   The spring frame cushion of claim 17, wherein the opposed side walls are part of a continuous frame.   27. The spring frame cushion of claim 26, wherein the continuous frame includes four side walls to define four corners. 28. The spring frame cushion of claim 27, wherein the first comb-like structure includes a protrusion extending around two of the four corners.

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