JP2011108698A - Wafer carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wafer carrier where dusting is prevented. <P>SOLUTION: The wafer carrier 10 includes: a lower unit 30 where a semiconductor wafer 200 is mounted; and an upper unit 20 to which the lower unit 30 is attachable, and where a sealed space to house the semiconductor wafer 200 is formed between the upper unit 20 and the attached lower unit 30. In the lower unit 30, a plurality of positioning members 40 that contact with circumference edge of the mounted semiconductor wafer 200 are provided along a circumferential direction. Each positioning member 40 is, for example, a roller member that is rotatable about an axis, and is rotatably supported. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a wafer carrier that accommodates a semiconductor wafer.

  In the manufacturing process of a semiconductor device, a very advanced clean environment is required due to miniaturization of a processing process. In order to realize such a clean environment, the manufacturing process of the SMIF (Standard Mechanical Interface) method that does not clean the entire manufacturing process uniformly but concentrates only on the space where the semiconductor wafer is present. Has been proposed. In the SMIF manufacturing process, an airtight container called a wafer carrier is used when a semiconductor wafer is transferred and stored. Each processing apparatus that performs various processes is provided with a load port device, and the wafer carrier is opened and closed by the load port device while being isolated from the atmosphere.

  Patent Document 1 discloses a conventional wafer carrier. The wafer carrier includes a lower unit that supports a semiconductor wafer and an upper unit to which the lower unit can be attached and detached. The upper unit forms a sealed space for accommodating the semiconductor wafer between the upper unit and the attached lower unit. The lower unit is provided with a plurality of positioning members in contact with the outer peripheral edge of the semiconductor wafer placed along the circumferential direction. The semiconductor wafer is placed at a fixed position with respect to the lower unit by the positioning member.

JP-A-5-175321

  When the positioning member is provided on the wafer carrier, for example, when the semiconductor wafer is taken in and out, the semiconductor wafer may be rubbed by the positioning member, and dust may be generated. However, if a positioning member is not provided on the wafer carrier, the semiconductor wafer is moved by the wafer carrier, and dust is also generated. In view of this problem, the present invention provides a wafer carrier in which dust generation is suppressed.

  A wafer carrier according to the present invention includes a lower unit on which a semiconductor wafer is placed, and an upper unit in which the lower unit is detachable and forms a sealed space for accommodating the semiconductor wafer between the lower unit to which the wafer carrier is attached. ing. The lower unit is provided with a plurality of positioning members in contact with the outer peripheral edge of the semiconductor wafer placed along the circumferential direction. In this wafer carrier, each positioning member is rotatably supported.

  In the wafer carrier described above, the positioning member can passively rotate with respect to the semiconductor wafer when the semiconductor wafer is taken in and out of the lower unit. Thereby, sliding between the semiconductor wafer and the positioning member is prevented, and generation of dust is significantly suppressed.

In the above-described wafer carrier, each positioning member is preferably rotatable at least about an axis parallel to the semiconductor wafer placed on the lower unit.
According to such a configuration, the positioning member can smoothly rotate with respect to the semiconductor wafer that is taken in and out of the lower unit. Here, as an example, each positioning member may be a roller member that can rotate around one axis, or a free bearing that supports the sphere so as to be rotatable in an arbitrary direction.

In the wafer carrier described above, it is preferable that at least one positioning member abuts on a notch formed on the outer peripheral edge of the semiconductor wafer.
According to such a configuration, the plurality of positioning members can not only position the semiconductor wafer but also determine the phase of the semiconductor wafer at the same time. That is, the wafer carrier can always support the semiconductor wafer in a constant phase.

  It is preferable that the positioning member in contact with the above-described notch has a different shape as compared with other positioning members. That is, it is preferable that what contacts the semiconductor wafer at the notch has a shape corresponding to the notch.

  According to the wafer carrier described above, dust generation caused by the positioning member can be significantly suppressed. However, the conventional wafer carrier has other locations that cause dust generation. For example, the wafer carrier of Patent Document 1 further includes a clamp member that clamps the upper unit and the lower unit. The clamp member is swingably supported by the upper unit and has a contact portion that contacts the lower unit at the clamp position.

  If the clamp member is provided on the wafer carrier, for example, when the clamp member opens and closes, the lower unit may be rubbed by the clamp member, and dust may be generated. However, if the clamping member is not provided on the wafer carrier, the upper unit and the lower unit cannot be firmly fixed, and the airtightness of the space for housing the semiconductor wafer may not be maintained.

In view of the above problems, when the wafer carrier includes the clamp member described above, the abutting portion is rotatably supported and can be passively rotated with respect to the upper unit or the lower unit in contact with the wafer carrier. Is preferred.
According to such a structure, when the clamp is opened and closed, the contact portion passively rotates, thereby preventing sliding between the upper unit or the lower unit and the contact portion, and generation of dust is significantly increased. It is suppressed.

The abutting portion of the clamp member is preferably rotatable at least about an axis parallel to the swing axis of the clamp member.
According to such a configuration, the contact portion can smoothly rotate with respect to the movement of the swinging clamp member. Here, as an example, a roller member that can rotate around one axis or a free bearing that supports a sphere so as to be rotatable in an arbitrary direction can be adopted as the contact portion.

Normally, the clamp member of the wafer carrier is opened / closed by a clamp opening / closing device provided in a load port device or the like. Therefore, it is preferable that the clamp member is provided with an engaging portion that engages with an external clamp opening / closing device, and the engaging portion is rotatably supported.
According to this configuration, when the clamp opening / closing device opens and closes the clamp member, the sliding between the engaging portion of the clamp member and the movable jig of the clamp opening / closing device is suppressed, and dust generated by the sliding is prevented. It can be significantly suppressed.

It is preferable that the engaging portion of the clamp member described above is rotatable at least about an axis parallel to the swing axis of the clamp member.
According to such a configuration, the engaging portion can smoothly rotate with respect to the movement of the movable jig of the clamp opening / closing device that swings the clamp member. Further, if the movable jig of the clamp opening / closing device is U-shaped, the engaging portion and the movable jig can be easily engaged, and sliding of both at the time of engagement can be prevented. Here, as an example, a roller member that can rotate around one axis or a free bearing that supports a sphere so as to be rotatable in an arbitrary direction can be adopted as the engaging portion.

  According to the wafer carrier of the present invention, dust generation associated with sliding of two members can be significantly suppressed.

The top view which shows the wafer carrier of an Example. It is the II-II sectional view taken on the line in FIG. 1, and shows the wafer carrier of the closed state. It is the II-II sectional view taken on the line in FIG. 1, and shows the wafer carrier of the open state. The top view of a regular positioning unit. The side view of a fixed positioning unit. The top view of the positioning unit for notches. The side view of the positioning unit for notches. The figure which shows the clamp member in a clamp position. The figure which shows the clamp member in an unclamp position. The figure which shows the load port apparatus with which the wafer carrier was mounted. The figure which shows a clamp opening / closing apparatus (state of a clamp position). The figure which shows a clamp opening / closing apparatus (state of an unclamp position). The figure which shows the load port apparatus which open | releases a wafer carrier.

First, the main features of the embodiment are listed.
(Mode 1) The wafer carrier includes an upper unit and a lower unit detachable from the upper unit. A cavity that opens downward is formed in the upper unit, and the lower unit can be attached to and detached from the opening. The lower unit hermetically closes the cavity of the upper unit, and a sealed space that can accommodate a semiconductor wafer is formed between the upper unit and the lower unit.
(Mode 2) The lower unit is provided with a plurality of positioning units. The plurality of positioning units are arranged in the circumferential direction with respect to the central axis of the semiconductor wafer placed on the lower unit. Each positioning unit has a positioning roller that contacts the outer peripheral edge of the semiconductor wafer, and a support block that rotatably supports the positioning roller. The support block is provided with a lower surface support portion that contacts the lower surface of the semiconductor wafer.
(Mode 3) The upper unit is provided with a plurality of clamp members. The clamp member is supported in a swingable manner, and can move between a clamp position that abuts on the lower surface of the lower unit and an unclamp position that is separated from the lower unit. The clamp member has a contact roller that is rotatably supported. When the clamp member is at the clamp position, the contact roller contacts the lower surface of the lower unit.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a wafer carrier 10 according to an embodiment. FIG. 2 is a cross-sectional view of the wafer carrier 10 taken along line II-II in FIG. 1 and shows the wafer carrier 10 in a closed state. FIG. 3 is a cross-sectional view of the wafer carrier 10 taken along the line II-II in FIG. 1, and shows the wafer carrier 10 in an open state. In FIG. 1, a part of the top plate 24 is not shown.

  The wafer carrier 10 is a container that hermetically accommodates the semiconductor wafer 200, and is used for transporting and transporting the semiconductor wafer 200 in the manufacturing process of the semiconductor device adopting the SMIF method. This type of wafer carrier 10 may be referred to as a clean box, for example.

  As shown in FIGS. 1 to 3, the wafer carrier 10 includes a lower unit 30 on which the semiconductor wafer 200 is placed and an upper unit 20 to which the lower unit 30 can be attached and detached. The upper unit 20 is formed with a cavity 22 that opens downward. The upper part of the cavity 22 is airtightly closed by the top plate 24. A lower unit 30 can be attached to and detached from the upper unit 20. When the lower unit 30 is attached to the upper unit 20, the cavity 22 of the upper unit 20 is airtightly closed. Thereby, a sealed space in which the semiconductor wafer 200 is accommodated is formed between the upper unit 20 and the lower unit 30.

  The lower unit 30 is provided with a plurality of positioning units 40. In this embodiment, five positioning units 40 are provided, but at least three positioning units 40 may be provided. The plurality of positioning units 40 are arranged along the circumferential direction with respect to the central axis of the semiconductor wafer 200 to be placed. The plurality of positioning units 40 abut on the semiconductor wafer 200 and support the semiconductor wafer 200 in a fixed position and a fixed phase (constant direction). Of the five positioning units 40, four positioning units 40a are of a fixed type, but one positioning unit 40b is for a notch. The fixed positioning units 40a are arranged at equal intervals in the circumferential direction, and the notch positioning units 40b are arranged at an intermediate position between the adjacent fixed positioning units 40a.

The positioning unit 40 will be described in detail with reference to FIGS. 4 and 5 show a plan view and a side view of the fixed positioning unit 40a, respectively. FIGS. 6 and 7 show a plan view and a side view of the positioning unit 40b for notches, respectively.
As shown in FIGS. 4 to 7, the fixed positioning unit 40 a includes a positioning roller 46 and a support block 42 that rotatably supports the positioning roller 46. The positioning roller 46 contacts the outer peripheral edge 200 e of the semiconductor wafer 200 to position the semiconductor wafer 200 in the surface direction. Although the positioning roller 46 is an example, it is made of PEEK resin so as to prevent the semiconductor wafer 200 from being contaminated.

  Here, as shown in FIGS. 6 and 7, the positioning unit 46b for the notch is different in the shape of the positioning roller 46, and can contact the notch 200n formed on the outer peripheral edge 200e of the semiconductor wafer 200. it can. By including the notch positioning unit 40b among the plurality of positioning members 40 as in the present embodiment, when the semiconductor wafer 200 is placed on the lower unit 30, the phase determination of the semiconductor wafer 200 (semiconductor wafer) (Specific orientation) can be performed at the same time.

  The positioning roller 46 is supported by a shaft 47. A radial bearing 48 is provided between the positioning roller 46 and the shaft 47, and the positioning roller 46 is supported so as to be rotatable about the shaft 47 as a central axis. When the positioning roller 46 is rotatably supported, the positioning roller 46 can passively rotate with respect to the semiconductor wafer 200 when the semiconductor wafer 200 is taken in and out of the lower unit 30. Thereby, sliding between the semiconductor wafer 200 and the positioning roller 46 is prevented, and the generation of dust is significantly suppressed. In particular, in the positioning roller 46 of this embodiment, a shaft 47 serving as a rotation axis extends parallel to the semiconductor wafer 200 to be placed. According to such a configuration, the positioning roller 46 can smoothly rotate with respect to the semiconductor wafer 200 that is taken in and out, and dust generation can be effectively suppressed. Instead of the positioning roller 46 that can rotate around one axis, a free bearing that supports the sphere so as to be rotatable in an arbitrary direction may be adopted.

  Each positioning unit 40 is formed with a lower surface support portion 44 that contacts the lower surface 200 b of the semiconductor wafer 200. The lower surface support portion 44 is formed integrally with the support block 42 of the positioning unit 40. The lower surface support portion 44 abuts on the lower surface 200 b of the semiconductor wafer 200 and defines the vertical position of the semiconductor wafer 200. In addition, as shown in FIGS. 1 and 2, the lower unit 30 is further provided with a center support unit 49. The center support unit 49 is located on the center axis of the semiconductor wafer 200 to be placed. The center support unit 49 has a conical shape, and supports the central portion of the semiconductor wafer 200 by its top. In the lower unit 30, the peripheral portion of the semiconductor wafer 200 is supported by the plurality of positioning units 40, and the peripheral portion of the semiconductor wafer 200 is supported by the center support unit 49. This prevents the mounted semiconductor wafer 200 from being bent.

As shown in FIGS. 1 to 3, the upper unit 20 is provided with a plurality of clamp members 50. The plurality of clamp members 50 clamp the upper unit 20 and the lower unit 30 and press-contact the upper unit 20 and the lower unit 30 to ensure the sealing of the accommodation space. Although not shown, a seal member is provided on the joint surface between the upper unit 20 and the lower unit 30.
The clamp member 50 is swingably supported by the upper unit 20, and can move between a clamp position shown in FIG. 2 and an unclamp position shown in FIG. As shown in FIG. 3, when the clamp member 50 moves to the unclamp position, the clamp by the clamp member 50 is released, and the lower unit 30 is removed from the upper unit 20, whereby the wafer carrier 10 can be opened. As will be described in detail later, the opening / closing operation for moving the clamp member 50 between the clamp position and the unclamp position is performed by the clamp opening / closing device 150 of the load port device 100.

The clamp member 50 will be described in detail with reference to FIGS. FIG. 8 shows the clamping member 50 in the clamping position, and FIG. 9 shows the clamping member 50 in the unclamping position.
As shown in FIGS. 8 and 9, the clamp member 50 is supported by a shaft 51 provided in the upper unit 20. The clamp member 50 can swing about the shaft 51 as a swing axis, and can swing between a clamp position approaching the lower unit 30 and an unclamp position spaced apart from the lower unit 30.

  The clamp member 50 is provided with a contact roller 52. The contact roller 52 is rotatably supported by a shaft 53. The contact roller 52 is provided at a position where it comes into contact with the lower unit 30. That is, when the clamp member 50 is in the clamp position, the contact roller 52 contacts the lower surface 30b of the lower unit 30, and when the clamp member 50 moves to the unclamp position, the contact roller 52 moves from the lower surface 30b of the lower unit 30. Get away.

  Since the contact roller 52 is rotatable, the contact roller 52 can passively rotate with respect to the movement of the clamp member 50 that is opened and closed. Thereby, when the clamp member 50 is opened and closed, sliding between the contact roller 52 and the lower unit 30 is prevented, and generation of dust is significantly suppressed. In particular, in the contact roller 52 of the present embodiment, the shaft 53 serving as the rotation shaft extends parallel to the shaft 51 serving as the swing shaft of the clamp member 50. According to such a configuration, the contact roller 52 can smoothly rotate with respect to the swinging movement of the clamp member 50, and dust generation can be effectively suppressed. Instead of the contact roller 52 that can rotate around one axis, a free bearing that supports the sphere so as to be rotatable in an arbitrary direction may be adopted.

  The clamp member 50 is provided with an engagement roller 54. The engagement roller 54 is rotatably supported by the shaft 55. The engagement roller 54 engages with a movable jig 152 of a clamp opening / closing device 150 described later. Here, the clamp opening / closing device 150 is provided in the load port device 100 shown in FIG. Therefore, prior to the description of the engagement roller 54, the load port device 100 will be described first.

  As shown in FIG. 10, the load port apparatus 100 is provided in a processing apparatus 170 that performs various processing processes on the semiconductor wafer 200. The load port device 100 is a device that opens and closes the received wafer carrier 10. The internal space 102 of the load port apparatus 100 and the internal space 172 of the processing apparatus 170 are cleaned at a higher level than the surrounding atmosphere.

The load port apparatus 100 includes a fixed stage 110 and a movable stage 120 on which the wafer carrier 10 is placed. The fixed stage 110 is a ring-shaped stage and surrounds the movable stage 120 located substantially at the center. The movable stage 120 can be moved up and down by the linear motion guide 130 and the cylinder device 132.
Vacuum channels 112 and 122 for adsorbing the wafer carrier 10 are formed in the fixed stage 110 and the movable stage 120, respectively. In the load port apparatus 100, when the wafer carrier 10 is placed, the wafer carrier 10 is supported only by the fixed stage 110, and a gap is formed between the movable stage 120 and the wafer carrier 10. . According to this configuration, the dust adhering to the bottom surface of the wafer carrier 10 can be sucked by the vacuum flow path 122 of the movable stage 120, and the load port device 100 and the processing device 170 can enter the internal spaces 102 and 172. Can be prevented.

Although not shown in FIG. 10, the clamp opening / closing device 150 is provided on the fixed stage 110. The clamp opening / closing device 150 is provided at a position corresponding to the clamp member 50 of the wafer carrier 10 to be placed. The clamp opening / closing device 150 will be described with reference to FIGS. 11 and 12.
As shown in FIGS. 11 and 12, the clamp opening / closing device 150 includes a movable jig 152 and a cylinder device 154 that moves the movable jig 152. The cylinder device 154 is an example of an actuator that moves the movable jig 152, and can be replaced with another type of actuator. The movable jig 152 is a generally U-shaped member, and has a slit 152a that opens upward.

  As shown in FIG. 11, when the wafer carrier 10 is placed on the load port device 100, the engagement roller 54 of the clamp member 50 engages with the slit 152 a of the movable jig 152. Here, the slit 152a is slightly larger than the diameter of the engagement roller 54, and a gap is formed between them. As described above, the engagement roller 54 is rotatably supported. Therefore, when the clamp member 50 and the movable jig 152 are engaged, the engagement roller 54 is passively rotated with respect to the movable jig 152, thereby sliding between the clamp member 50 and the movable jig 152. Is suppressed. Thereby, dust generation can be suppressed significantly.

  The movable jig 152 engaged with the engagement roller 54 is moved in a direction away from the wafer carrier 10 by the cylinder device 154. Thereby, as shown in FIG. 12, the clamp member 50 moves to the unclamping position. Also in the opening operation of the clamp member 50, the sliding between the clamp member 50 and the movable jig 152 is suppressed by the passive rotation of the engagement roller 54. Thereby, dust generation is significantly suppressed.

  As shown in FIG. 13, when the clamp by the clamp member 50 is released, the load port device 100 opens the wafer carrier 10 by lowering the movable stage 120. The semiconductor wafer 200 is drawn into the internal space 102 of the load port apparatus 100 together with the lower unit 30. The semiconductor wafer 200 moved into the load port apparatus 100 is picked up by the robot arm 180 and carried into the processing apparatus 170. When picking up the semiconductor wafer 200, the positioning roller 46 is passively rotated to suppress dust generation. After the processing process by the processing apparatus 170 is completed, the semiconductor wafer 200 is accommodated in the wafer carrier 10 by a flow reverse to the above. The wafer carrier 10 containing the semiconductor wafer 200 again is sent to another processing apparatus 170 that performs the next processing process.

As described above, in the wafer carrier 10 of this embodiment, the positioning roller 46 that is rotatably supported by the positioning member of the semiconductor wafer 200 is employed. Thereby, the dust generation accompanying the contact of the semiconductor wafer 200 and the positioning member can be significantly suppressed.
Further, in the wafer carrier 10 of this embodiment, a contact roller 52 that is rotatably supported is provided at a portion of the clamp member 50 that contacts the lower unit 30. Thereby, the dust generation accompanying the contact of the clamp member 50 and the lower unit 30 can be suppressed significantly.

Further, in the wafer carrier 10 of the present embodiment, a rotatable engagement roller 54 is provided on the clamp member 50, and the engagement roller 54 is engaged with the movable jig 152 of the clamp opening / closing device 150. Thereby, the dust generation accompanying the contact of the clamp member 50 and the movable jig 152 can be significantly suppressed.
As described above, in the wafer carrier 10 of this embodiment, it is possible to realize a high-level clean environment by arranging a rotatable member at a contact location that may cause dust generation.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

10: Wafer carrier 20: Upper unit 30: Lower unit 40, 40a, 40b: Positioning unit 46: Positioning roller 50: Clamping member 52: Contact roller 54: Engaging roller 100: Load port device 150: Clamp opening / closing device 152: Movable jig 152a of clamp opening / closing device: slit 200 of movable jig: semiconductor wafer 200e outer periphery 200n of semiconductor wafer: notch of semiconductor wafer

Claims (10)

A wafer carrier for housing a semiconductor wafer,
A lower unit on which a semiconductor wafer is placed;
The lower unit is detachable, and includes an upper unit that forms a sealed space for accommodating a semiconductor wafer between the lower unit and the attached lower unit.
The lower unit is provided with a plurality of positioning members in contact with the outer peripheral edge of the semiconductor wafer placed along the circumferential direction.
Each positioning member is supported so that rotation is possible, The wafer carrier characterized by the above-mentioned.   2. The wafer carrier according to claim 1, wherein each positioning member is rotatable at least about an axis parallel to a semiconductor wafer placed on the lower unit.   The wafer carrier according to claim 1, wherein the at least one positioning member abuts on a notch formed on an outer peripheral edge of the semiconductor wafer.   4. The wafer carrier according to claim 1, wherein the positioning member that contacts the notch has a different shape as compared with the other positioning members. 5. A clamp member for clamping the upper unit and the lower unit;
The clamp member is swingably supported by one of the upper unit and the lower unit, and has a contact portion that contacts the other of the upper unit and the lower unit at the clamp position.
The wafer carrier according to claim 1, wherein the contact portion is rotatably supported.   6. The wafer carrier according to claim 5, wherein the contact portion of the clamp portion is rotatable at least about an axis parallel to the swing axis of the clamp member. The clamp member is provided with an engaging portion that engages with an external clamp opening and closing device,
The wafer carrier according to claim 5 or 6, wherein the engaging portion is rotatably supported.   8. The wafer carrier according to claim 7, wherein the engaging portion is rotatable at least about an axis parallel to the swing axis of the clamp member.   The wafer carrier according to any one of claims 5 to 8, wherein the engaging portion is engageable with a U-shaped movable member provided in the clamp opening / closing device. A wafer carrier for housing a semiconductor wafer,
A lower unit on which a semiconductor wafer is placed;
An upper unit that is detachable from the lower unit and forms a sealed space for housing a semiconductor wafer between the lower unit and the attached lower unit;
It has a clamp member that clamps the upper unit and lower unit,
The clamp member is supported by one of the upper unit and the lower unit so as to be swingable between the clamp position and the unclamp position, and has a contact portion that contacts the other of the upper unit and the lower unit at the clamp position. And
The wafer carrier is characterized in that the contact portion is rotatably supported.

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