JP2012049217A - Substrate storage container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate storage container preventing an increase in resistance when removing a lid body.SOLUTION: A substrate storage container includes: a container main body that has an opening, and is capable of storing a substrate; a lid body closing the opening of the container main body; and a gasket for sealing provided in the lid body. When the lid body is attached to the container main body to be fixed; force for removing the lid body in an initial state is defined as F0; and force for removing the lid body after the lapse of 72 hours is defined as F1, FO is smaller than 20 N, and the value of (F1-F0)/F0 is 2.0 or less.

Description

  The present invention relates to a seal gasket used for a substrate storage container used for storing, storing, transporting, transporting articles such as a substrate made of a semiconductor wafer.

As a substrate storage container, there is known a substrate storage container having a container body that has an opening in the front and stores a plurality of substrates arranged in a fixed interval inside, and a lid that closes the opening in a sealable manner. ing. The lid of the substrate storage container incorporates a locking mechanism that can be operated from the outside, and a front retainer that holds the substrate is attached to the inner surface of the lid. A gasket for sealing is provided on the side wall of the lid, and the opening of the substrate storage container body is closed by the lid so as to be sealed.
The lid is automatically opened and closed by a lid opening / closing device (LP device) provided in the processing apparatus or the like, and the substrate is loaded or unloaded.

  Various conveying means such as a robotic flange provided on the top surface and a conveyor rail provided on the bottom surface are attached to the substrate storage container, and automatic conveyance such as ceiling conveyance and conveyor conveyance is possible. It is used to transport and store a substrate in a process for processing and processing.

  As disclosed in Patent Document 1, as a gasket for a substrate storage container, an endless portion that fits into a fitting groove and a projecting piece that extends obliquely outward from one side of the endless portion are in contact with the inner surface of the opening of the container body. What forms a seal is known.

JP 2002-68364 A

Problems to be solved by the invention

Nowadays, semiconductor wafers are beginning to be examined for a transition from a diameter of 300 mm to 450 mm. On the other hand, electronic circuits that are processed into semiconductor wafers are becoming increasingly finer with a minimum line width of 90 nm to 40 nm or less, and when semiconductor wafers are transported and stored in substrate storage containers. In addition, further consideration is required so that the semiconductor wafer is not contaminated by particles or organic contaminants.
Therefore, the substrate storage container is required to be sealed for a long period of time so that particles, organic contaminants, and the like do not enter the substrate storage container from the outside. In addition, it has been difficult to uniformly seal the inner peripheral surface of the container body having a large opening due to dimensional errors.

On the other hand, if it compresses strongly so that the sealing performance of a gasket member may be exhibited sufficiently, the inner surface of the opening of the container main body and the gasket will come into surface contact with each other, which makes it easy to stick. In addition, if the container body is stored for a long time with the lid closed, the gasket creeps and the seal forming part changes from line contact to surface contact, increasing the contact area. As a result, it sticks to the container body, and it may occur that the resistance when removing the lid increases.
If the contact area is increased and the sticking force is increased in this way, when the lid is removed from the container body using the LP device, the opening / closing operation of the lid is stopped due to a load caused by the sticking of the gasket. Trouble occurred.

  The present invention has been made in view of the above problems, and the substrate storage container of the present invention has an opening, a container main body capable of storing a substrate, a lid for closing the opening of the container main body, and a lid. A substrate storage container having a sealing gasket provided on the body, the lid body being attached and fixed to the container main body, the removal force of the lid body in the initial state is F0, and the lid body is removed after 72 hours When the force is F1, F0 is smaller than 20N, and the value of (F1-F0) / F0 is 2.0 or less.

  The gasket has an endless portion and a projecting piece that forms a seal, and at least one of the endless portions is fitted into a fitting groove formed in the lid, and is positioned on the opening side of the fitting groove of the endless portion. A protrusion is formed on the other side of the protrusion, and a sticking prevention means is further formed or a sticking prevention measure is provided on the seal forming surface side of the protrusion; It is preferable that the crushing margin of the protruding piece of the gasket when closing is restricted to be 0.6 mm or less.

  Furthermore, the sticking prevention means is a spherical protrusion formed so as to face the seal forming surface, and the spherical protrusion is in contact with the seal forming surface of the container body, the protruding piece, It is also preferable to have a horizontal part that extends horizontally from the endless part and a curved part that is curved from the end of the horizontal part.

  In the gasket of the present invention, since the spherical protrusion is prevented from adhering to the portion facing the seal forming surface of the projecting piece forming the seal, it is possible to prevent the gasket member from adhering while maintaining the sealing performance. become. Accordingly, the substrate storage container can be kept sealed for a long period of time, and contamination of the substrate can be prevented. Further, the load does not increase when the lid is opened and closed by the lid opening / closing device, and the productivity when processing the substrate is not lowered.

It is a disassembled perspective view showing the substrate storage container of this invention. It is a front view showing the cover body of the substrate storage container of this invention. It is a top view showing the gasket of this invention. FIG. 4 is a sectional view taken along line AA in FIG. 3. It is a partial expanded sectional view at the time of unlocking of the locking mechanism of the BB line of FIG. It is a partial expanded sectional view at the time of locking of the locking mechanism of the BB line of FIG. It is sectional drawing explaining the height of a gasket in order to define the amount of crushing of the seal part of a gasket, Comprising: It is a figure showing height H0 before a gasket contacts a seal formation surface. It is sectional drawing explaining the height of a gasket in order to define the amount of crushing of the seal part of a gasket, Comprising: It is a figure showing height H1 of the state which a gasket contacts the seal formation surface and forms the seal | sticker. is there.

  FIG. 1 is a perspective view of a substrate storage container for storing a semiconductor wafer. The substrate storage container includes a container main body 1 having an opening 3 for storing a semiconductor wafer on the front surface and a pair of support portions 4 on an inner wall. The lid 2 has a lid 2 that closes the opening 3 of the container body 1 and a front retainer 5 that holds the semiconductor wafer. The lid 2 has a locking mechanism 6 that fixes the lid 2 to the container body 1. A sealing gasket 7 is provided on the side of the lid 2. The opening 3 of the container body 1 is sealed by being closed by the lid 2.

  A robotic flange 8 for transportation is attached to the top surface of the container body 1, and a bottom plate (not shown) having a conveyor rail for transportation is provided at the bottom. Three positioning members (not shown) are disposed on the bottom plate and the bottom surface of the container body 1 and are fitted to the positioning pins of the apparatus to center the apparatus and the substrate storage container.

  As shown in an enlarged view in FIG. 2, the pair of locking mechanisms 6 incorporated in the lid body 2 includes an operation hole 10 that can be accessed from the outside, a rotation member 11 that is rotated by the operation hole 10, and the rotation member 11. The latch bar 12 that moves in the vertical direction in the figure and the latch bar 12 is locked to the tip of the latch bar 12 and protrudes and retracts from the through hole 13 on the lid side wall into the locking recess 14 (FIG. 1) of the container body 1. And a locking portion 15 to be engaged.

  FIG. 3 is a plan view showing the gasket of the embodiment of the present invention, and FIG. 4 is an enlarged cross-sectional view showing the main part of the gasket in a state where the AA line part of FIG. 3 is cut. The gasket 7 includes an endless portion 16 having a substantially rectangular shape and a projecting piece 17 for forming a seal that protrudes from the outside of the endless portion 16. Two rows of fitting ribs 18 a and 18 b are formed on the upper surface of the endless portion 16, and the inner rib 18 a has a cross section formed in a columnar shape with an arc at the tip, and the outer rib 18 b includes an inclined surface 19. Furthermore, it is formed in a larger and higher cross-sectional triangle shape.

  The projecting piece 17 has a horizontal portion 20 that extends horizontally from a corner portion on the outer upper side of the endless portion 16, and a curved portion 21 that obliquely extends upward from an end portion of the horizontal portion 20. A spherical protrusion 22 is formed on the surface. On the upper surface of the bending portion 21, a spherical protrusion serving as an anti-sticking means 23 having a semicircular cross section is further provided.

5 and 6 are partially enlarged cross-sectional views of the locking mechanism 6 built in the lid, FIG. 5 shows a state when unlocking, and FIG. 6 shows a state when locking.
That is, in FIG. 5, the locking portion 15 moves away from the locking recess 14, and the lid 2 moves so as to slightly protrude from the opening of the container body 1. This represents a state in which the seal has been eliminated. In addition, 24 is a gasket accommodation recessed part, 25 is a seal formation surface.
6 shows that the locking mechanism 5 is locked from the state of FIG. 5, the locking portion 15 is inserted into the locking recess 14 and engaged, and the lid 2 seals with the container body 1. The formed state is shown.

  Here, in the gasket of the present embodiment, the sticking prevention means 23 is formed on the projecting piece 17 serving as a seal forming portion, and the increase in the contact area of the projecting piece 17 is limited. Even in a state of being attached for a long time, it is possible to prevent the projecting piece from excessively contacting and sticking to the seal forming surface. Further, since the sticking prevention means 23 is formed so as to face the seal forming surface 25, the sticking prevention means that has been compressed by unlocking the locking mechanism attempts to return to its original shape. The protruding piece can be slightly lifted from the seal forming surface, and when removing the lid from the container body, an excessive load is not applied to the lid opening / closing device, and the lid opening / closing device is attached by attaching a gasket. Stop trouble can be prevented, and the productivity of the substrate is not reduced.

  The gasket material can be formed from rubber such as fluorine rubber, EPDM, NBR, urethane rubber, various thermoplastic elastomers such as polyester, polyolefin, and polystyrene. Preferably, the hardness of such raw materials can be 60 ° or more and 80 ° or less, particularly preferably in the range of 60 ° or more and 70 ° or less when measured according to the measurement method of JIS 6253 type A. If the hardness is 60 ° or more, by providing a sticking prevention means, it is possible to prevent the seal forming portion of the gasket member from coming into surface contact with the seal forming surface of the container body due to creep deformation and sticking. The lid opening / closing operation is not stopped when the lid is opened and closed by an automatic machine. If it is 80 ° or less, the reaction force when the lid is pressed against the container body can be 110 N or less which does not exceed the capacity of the device, so that it can be handled by the current lid opening / closing device. In addition, by setting the range to 60 ° or more and 70 ° or less, the generation of particles when the lid is repeatedly opened and closed can be minimized.

Moreover, it is possible to prevent the sticking resistance of the gasket member from increasing with time by regulating the crushing amount T of the seal portion of the gasket.
The crushing amount T of the seal part of the gasket is H0, the height before the gasket comes into contact with the seal formation surface, and H1, the height when the gasket is in contact with the seal formation surface and forms a seal. Is defined by T = H0−H1.
In this embodiment, when the cover is attached to the container body, the gasket is crushed by reducing the protrusion amount of the seal forming portion of the gasket so that the collapse amount T of the gasket is less than 1 mm, preferably 0.6 mm or less. The amount of change with time of the attached resistance can be significantly reduced.

  In this embodiment, the sticking prevention means is formed on the gasket. However, in order to obtain a more effective effect, a diamond-like carbon coating or a silicon-based resin is formed on the projecting piece forming the gasket seal or the seal forming surface of the container body. It is possible to prevent the sticking by coating the surface to the extent that it does not impair the seal.

Examples having the cross-sectional shape as shown in FIG. 4 having spherical protrusions in the seal portion and the crushing amount of the seal forming portion being 0.2 mm, 0.3 mm, and 0.4 mm, respectively, are designated as Examples 1, 2, and 3. As shown in FIG. 7, instead of forming spherical protrusions on the seal portion, Examples 4 and 5 were used in which the height of the seal portion was lowered and the crushed amount was 0.6 mm.
These gaskets are made of fluororubber with hardness of 60 °, 70 °, and 75 °, incorporated in the substrate storage container, and the load required to remove the lid in the initial state when the lid is locked to the container body is measured. Then, the load required for removing the lid after storing the lid in a closed state for a predetermined time was measured. Similarly, Example 6 was a gasket formed from fluoro rubber having a hardness of 65 ° so that the crushing margin was 0.6 mm.
In addition, a substrate storage container containing 25 semiconductor wafers with a diameter of 300 mm is set in a lid automatic opening / closing device, and the number of particles generated on the substrate before and after the lid is repeatedly opened and closed 100 times is measured. This was confirmed using a machine.
A comparison was made between the number in the initial state and the number after the open / close test, and the case where the number of particles increased was 10 or less was regarded as acceptable.

For comparison, a fluororubber having a hardness of 65 °, 70 °, and 85 ° was used as a material, and a gasket having no spherical protrusion formed on the seal portion was formed so that the crushed amount was 1.5 mm and 1.0 mm. As the comparative examples 1, 2, and 3, the load necessary for removing the lid was measured in the same manner.
Table 1 summarizes the change over time in the load required for removing the lid.
In Table 1, it is preferable that the change with time of the load necessary for removing the lid ((F1-F0) / F0)) is less than 2.

DESCRIPTION OF SYMBOLS 1 Container body 2 Lid 3 Opening 4 Support part 5 Front retainer 6 Locking mechanism 7 Gasket 8 Robotic flange 10 Operation hole 11 Rotating member 12 Latch bar 13 Through hole 14 Locking recessed part 15 Locking part 16 Endless part 17 Projection piece 18a, b Rib 19 Inclined surface 20 Horizontal portion 21 Curved portion 22 Spherical protrusion 23 Sticking prevention means 24 Gasket housing recess 25 Seal forming surface gasket contact portion

Claims (5)

  A substrate storage container having an opening and a container main body capable of storing a substrate, a lid for closing the opening of the container main body, and a sealing gasket provided in the lid, wherein the lid is attached to the container main body F0 is smaller than 20N, and (F1-F0) / F0, where F0 is the removal force of the lid in the initial state and F1 is the removal force of the lid after 72 hours. A substrate storage container having a value of 2.0 or less.   The gasket has an endless portion and a projecting piece that forms a seal, and at least one of the endless portions is fitted into a fitting groove formed in the lid, and is positioned on the opening side of the fitting groove of the endless portion. A protrusion is formed on the other side of the protrusion, and a sticking prevention means is further formed or a sticking prevention measure is taken on the seal forming surface side of the protrusion. The substrate storage container as described.   3. The substrate storage container according to claim 1, wherein when the lid is attached to the container body and fixed, a crushing margin of the protruding piece of the gasket is regulated to be 0.6 mm or less.   The said sticking prevention means is a projection part protrudingly formed so as to face the seal formation surface, and this projection part is in contact with the seal formation surface of the container body. Substrate storage container.   5. The substrate storage container according to claim 2, wherein the projecting piece has a horizontal portion that extends horizontally from the endless portion, and a curved portion that is curved from the end of the horizontal portion.

Images