JP2011096925A - Removing device and removing method of convex portion in semiconductor wafer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a removing device and a removing method of a convex portion in a semiconductor wafer which prevents a trouble in an expanding step or the like to be performed afterward by removing the convex portion even if the wafer has the convex portion at an outer edge thereof. <P>SOLUTION: By adsorbing and holding a concave portion bottom surface WB by a concave portion supporting means 4 and lowering it while supporting a convex portion WA of a wafer W by a convex portion supporting means 3, the convex portion WA can be separated from the wafer W and only a wafer W' corresponding to a concave portion WC can be left in a tape T for mounting. Accordingly, in a post process, when the tape T for mounting is extended before bonding (pickup), since the convex portion WA does not obstruct, each chip can be expanded at a proper interval, and the chip expanded at a predetermined position can be certainly picked up and bonded efficiently. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an apparatus and method for removing a convex portion of a semiconductor wafer.

  Conventionally, in a semiconductor manufacturing process, a semiconductor wafer (hereinafter sometimes simply referred to as a wafer) is cut into a predetermined shape and a predetermined size and separated into semiconductor chips (dicing process). After expanding (expanding process), each chip is picked up and bonded to the substrate (bonding process). Among these processes, an expanding apparatus that expands a diced chip has been proposed (see, for example, Patent Document 1). The expanding apparatus described in Patent Document 1 supports a wafer integrated with a ring frame via an adhesive sheet from the adhesive sheet side, and extends the adhesive sheet to the outside of the wafer to increase the chip interval. It is configured with a stage.

  On the other hand, in the dicing process in the semiconductor manufacturing process, the back surface of the wafer is ground to reduce the thickness of the semiconductor chip. In this grinding process, the inside of the wafer is ground deeper than the outer edge portion. Thus, a semiconductor wafer is known in which the inner side is formed thinner than the outer edge part, that is, the outer edge part has an annular convex part protruding in the thickness direction and the inner part surrounded by the convex part has a concave part (for example, , See Patent Document 2).

JP 2005-57158 A JP 2007-19461 A

  By the way, in the wafer which has a convex part in the outer edge part as described in patent document 2, since it cut | disconnects according to the thickness of a recessed part in a dicing process, only a part is cut | disconnected in the thickness direction with respect to a convex part. However, since the convex portion remains in an annularly continuous state, there is an inconvenience that even if the adhesive sheet is stretched outward in the expanding step, the convex portion interferes with the expansion. Also, when the adhesive sheet is stretched outward in the expanding process, the convex part may crack and expand, but the convex part cannot be expected to crack evenly, and it will be unevenly cracked. Further, there is a problem in that the distance between the expanded chips varies, and the pickup cannot be accurately picked up and the bonding is hindered.

  An object of the present invention is to remove a convex portion of a semiconductor wafer that can prevent a hindrance in an expanding process performed later by removing the convex portion even if the wafer has a convex portion on an outer edge portion. It is to provide an apparatus and a removal method.

  In order to achieve the above object, a semiconductor wafer convex portion removing apparatus according to the present invention has an annular convex portion protruding to one side in a thickness direction at an outer edge portion and a semiconductor having a concave portion inside surrounded by the convex portion. A device for removing a convex portion of a semiconductor wafer that removes the convex portion from a wafer, wherein the semiconductor wafer is held on one side of the semiconductor wafer via an adhesive sheet affixed to the entire region of the convex portion and the concave portion. The holding means includes a convex portion supporting means for supporting the convex portion, a concave portion supporting means for holding the concave bottom surface, and the convex portion supporting means and the concave portion supporting means orthogonal to the surface of the semiconductor wafer. And a moving means for separating the convex portion from the semiconductor wafer by relative movement in the direction to be adopted.

At this time, it is preferable that the convex removing device for a semiconductor wafer of the present invention includes a pressing unit that sandwiches a bottom region of the concave between the convex supporting unit and can be driven synchronously with the moving unit.
In the semiconductor wafer convex portion removing apparatus of the present invention, it is preferable that a recovery means for recovering the separated convex portions is provided.
Furthermore, in the convex part removal apparatus for a semiconductor wafer according to the present invention, the adhesive sheet is an energy ray curable adhesive sheet, and is opposed to the adhesive sheet affixed to the convex part surface, and energy rays are applied to the adhesive sheet. It is preferable to include an energy beam irradiation means for irradiating

  Further, the method for removing a convex portion of a semiconductor wafer according to the present invention includes an annular convex portion protruding in one of the thickness directions at an outer edge portion and the convex portion from a semiconductor wafer having a concave portion inside surrounded by the convex portion. A method for removing a convex portion of a semiconductor wafer, wherein the convex portion is held by a convex portion supporting means via an adhesive sheet affixed to the entire region of the convex portion and the concave portion on one side of the semiconductor wafer. The concave bottom surface is held by the concave portion supporting means via the adhesive sheet, and the convex portion is moved from the semiconductor wafer by relatively moving the portion supporting means and the concave portion supporting means in a direction perpendicular to the surface of the semiconductor wafer. It is characterized by separating.

According to the present invention as described above, since the convex portion can be removed prior to the expanding step or the like, when the adhesive sheet is stretched in the expanding step or the like, the convex portion is not disturbed, Chips can be expanded at appropriate intervals. Moreover, since the convex portion supporting means and the concave portion supporting means constituting the holding means for holding the semiconductor wafer can be separated from the convex portion and the concave portion only by relatively moving in the direction orthogonal to the surface of the semiconductor wafer, The device can be simplified and downsized.
Furthermore, if the pressing means that can be driven synchronously with the moving means by sandwiching the bottom surface area of the concave portion between the convex portion supporting means and the convex portion supporting means, the concave bottom surface can be reliably moved relative to the convex portion.
When the adhesive sheet is an energy ray curable sheet, the adhesive sheet on the surface of the convex portion is cured by irradiating the adhesive sheet affixed to the surface of the convex portion with the energy ray irradiating means, so that the convex portion is cured. Can be easily peeled off, and the convex portion can be easily and reliably removed.

The fragmentary sectional view of the convex part removal device of the semiconductor wafer concerning one embodiment of the present invention. Operation | movement explanatory drawing of the convex part removal apparatus of FIG. Operation | movement explanatory drawing following FIG. 2 of the convex part removal apparatus of FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
The semiconductor wafer convex portion removing apparatus 1 according to the present embodiment is an apparatus that removes the convex portion WA formed on the outer edge portion of the wafer W. Note that the target wafer W is, for example, as described in Patent Document 2, an annular protrusion protruding in the thickness direction (back surface side) by thinly grinding the inner peripheral portion other than the outer edge portion. A portion WA is formed on the outer edge, and a concave portion WC having a concave bottom surface WB is formed on the inner side surrounded by the convex portion WA, and the surface thereof (the surface opposite to the grinding surface, the upper surface in FIG. 1) A circuit is formed in the WD. Further, the wafer W may be a piece that has been diced into chips of a predetermined shape by dicing, a one whose street has been weakly modified by a laser, or one that has not been modified by dicing or laser. . A mounting tape T, which is an adhesive sheet, is attached to the entire rear surface of the wafer W over the convex portion WA and the concave bottom surface WB, and is integrated with the ring frame RF via the mounting tape T. The mounting tape T is an energy ray curable adhesive sheet that is cured by energy rays such as ultraviolet rays and has a reduced adhesive force.

  The convex removing device 1 collects the holding means 2 for holding the wafer W via the mounting tape T, the pressing means 7 for pressing the wafer W toward the holding means 2, and the convex WA separated from the wafer W. And collecting means 8 to be configured.

  The holding means 2 includes a convex support means 3 that faces the lower portion of the convex portion WA and holds the convex portion WA via the mount tape T, and a mounting tape T that faces the lower portion of the concave bottom surface WB of the wafer W. The concave portion supporting means 4 that holds the concave portion bottom surface WB, and the convex portion supporting means 3 and the concave portion supporting means 4 are moved relative to each other in a direction perpendicular to the surface of the wafer W to separate the convex portion WA from the wafer W. And means 5.

  The convex portion support means 3 includes a central concave portion 21 formed of a cylindrical side surface portion 21A and a bottom surface portion 21B opened upward, a concave groove portion 41 opened upward along the outer periphery of the central concave portion 21, and a convex portion WA. The support means main body 22 includes an outer support portion 61 that holds the mounting tape T that is located outside and extends to the ring frame RF. The opening of the concave groove 41 is provided with a transmission member 42 made of a glass plate or the like that faces the lower portion of the convex portion WA in a state of being flat with the upper surface of the support means main body 22 and that can transmit energy rays. And the ultraviolet lamp 6 as an energy ray irradiation means is incorporated in the inside of the concave groove part 41, and the ultraviolet light emitted from the ultraviolet lamp 6 is transmitted through the transmission member 42, so that the mount attached to the convex part WA. The adhesive tape T is cured to reduce its adhesive strength. The outer support portion 61 is constituted by the upper surface of the support means main body 22, and a plurality of suction ports 51 for sucking and holding the ring frame RF via the mounting tape T are formed on the upper surface, and the plurality of suction ports 51. Is connected to a suction device (not shown) through a chamber 52 formed in the support means body 22. A heater H as a heating means is provided along the outer periphery of the central recess 21 inside the support means main body 22.

  The recess support means 4 is formed in substantially the same plane shape as the entire area of the recess bottom surface WB, and includes an inner support means 23 that is slid vertically guided by the central recess 21, and the inner support means 23 is provided via the moving means 5. It is supported by the bottom surface portion 21 </ b> B and is driven to advance and retract in the vertical direction in the drawing by the operation of the moving means 5. On the upper surface of the inner support means 23, a plurality of suction ports 31 for sucking and holding the recess bottom surface WB via the mounting tape T are formed. These suction ports 31 are chambers formed inside the inner support means 23. A suction device (not shown) is connected via 32.

  The moving means 5 includes a linear motor 34, the motor main body 34 </ b> A is fixed to the bottom surface portion 21 </ b> B, and the output shaft 34 </ b> B is coupled to the lower surface of the inner support means 23 in FIG. 1. Thus, the convex portion WA can be separated from the wafer W by relatively moving the support means main body 22 and the inner support means 23 in a direction perpendicular to the concave bottom surface WB of the wafer W.

  The holding means 7 is formed in a disc shape in accordance with the planar shape of the concave bottom surface WB of the wafer W, and is formed in an annular shape along the outer peripheral edge of the lower surface of FIG. An abutting member 72 capable of abutting on the surface WD and a linear motion motor 73 supported by a frame (not shown) and moving the support 71 up and down in FIG. 1 are provided. Although the contact member 72 is not particularly limited, the contact member 72 is made of an elastic member such as rubber or resin, and is a boundary region between the convex portion WA and the concave bottom surface WB, and is opposite to the concave bottom surface WB (surface WD). ) And the inner support means 23 so as to sandwich the concave bottom surface WB region. In addition, the contact member 72 may be formed in a disk shape in accordance with the planar shape of the bottom surface WB of the recess in addition to the ring shape.

  The recovery means 8 removes the convex portion WA by winding the removal tape PT after the removal tape PT having an adhesive layer on the lower surface side in FIG. It is supported above the holding means 2 via a frame (not shown). The collection means 8 supports the removal tape PT in a rolled state, and supports the removal tape PT at a predetermined height above the holding roller 81 and the holding means 2 that can be rotated by a motor 81A. Two guide rollers 82A and 82B for guiding, a pressing roller 83 that can roll in the left-right direction in FIG. 1 along the upper surface of the holding means 2 via a driving means (not shown), and a motor 84A are driven to rotate. And a recovery roller 84 that winds and recovers the removal tape PT from the pressing roller 83. Then, when the rolling roller 83 rolls in the right direction in FIG. 1, the collecting means 8 presses and applies the removal tape PT to the convex portion WA and rolls in the left direction in the pressing roller 83 in FIG. 1. At this time, the convex portion WA adhered to the removal tape PT together with the removal tape PT is peeled off from the mounting tape T and collected.

  In the above-described convex portion removing apparatus 1, as a procedure for removing the convex portion WA of the wafer W, first, the wafer W integrated with the ring frame RF is conveyed by a conveying means (not shown) via the mounting tape T, The concave portion WC is positioned on the concave portion support means 4, the convex portion WA is positioned on the transmission member 42, and the ring frame RF is positioned on the outer side support portion 61. Next, the holding means 2 drives a suction device (not shown) to suck air from the plurality of suction ports 31, 51, and sucks and holds the recess bottom surface WB by the recess support means 4 via the mounting tape T. The outer support portion 61 sucks and holds the mounting tape T and the ring frame RF outside the convex portion WA. Then, the mounting tape T in the convex portion WA is irradiated with ultraviolet rays from the ultraviolet lamp 6 to be cured.

  Next, as shown in FIG. 2, the linear motion motor 73 is driven to bring the contact member 72 into contact with the surface WD of the wafer W. Thereafter, the linear motion motor 34 and the linear motion motor 73 are driven synchronously while the concave bottom surface WB and the ring frame RF are attracted and held by the plurality of suction ports 31, 51, and the inner support means 23 is moved relative to the support means main body 22. To lower. That is, the convex portion WA is separated from the wafer W by relatively moving the concave portion supporting means 4 and the convex portion supporting means 3 up and down. When the convex portion WA is separated from the wafer W, the linear motion motor 73 is driven to separate the contact member 72 from the surface WD of the wafer W as shown in FIG. Next, as shown by a two-dot chain line in FIG. 3, while the motor 84A is driven to feed out the removal tape PT from the collection roller 84, the rolling roller 83 rolls in the right direction in the figure to remove the removal tape. PT is pressed and stuck on the convex part WA. After the removal tape PT is pasted on the entire upper surface of the convex portion WA, the motor 84A is driven to wind the removal tape PT with the collection roller 84, and the pressing roller 83 is rolled in the left direction in the drawing, thereby producing the convex portion. The WA is peeled off from the mounting tape T, wound around the collection roller 84, and collected. When the convex portion WA is peeled off from the mounting tape T, the mounting tape T having a step is flattened by removing the convex portion WA by heating with the heater H. When the recovery of the convex portion WA is completed, the motors 81A and 84A co-operate, and the unused removal tape PT used for recovery of the next convex portion WA is moved from the support roller 81 side to the recovery roller 84 side. The operation of feeding out is performed.

  On the other hand, the wafer W ′ left in the recess supporting means 4 together with the mounting tape T and the ring frame RF is transferred to the bonding apparatus or the like by the transfer means (not shown) together with the ring frame RF.

According to this embodiment as described above, the following effects are obtained.
That is, since the convex portion WA can be removed at the stage before the expanding step, the convex portion WA does not get in the way in the expanding step, and each chip can be expanded at an appropriate interval, and the predetermined position It is possible to reliably pick up the expanded chip and perform bonding efficiently.

  As described above, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described with particular reference to certain specific embodiments, but without departing from the spirit and scope of the invention, Various modifications can be made by those skilled in the art in terms of material, quantity, and other detailed configurations. In addition, the description of the shape, material, and the like disclosed above is exemplary for ease of understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

  For example, in the above-described embodiment, the concave portion supporting means 4 is moved downward to separate the convex portion WA from the wafer W by lowering the concave portion supporting means 4 relative to the convex portion supporting means 3. Alternatively, the convex support means 3 may be raised. Further, the concave portion supporting means 4 may be lowered and the convex portion supporting means 3 may be raised. That is, in the present invention, it is sufficient that the moving means is configured to relatively move the convex portion supporting means 3 and the concave portion supporting means 4 in the direction perpendicular to the surface of the wafer W (the vertical direction in the embodiment). As long as the conditions are satisfied, the moving object and the moving direction are not particularly limited, and any configuration can be adopted as the moving means.

Moreover, the ultraviolet lamp 6, the pressing means 7, and the recovery means 8 as the energy beam irradiation means in the embodiment are not essential requirements of the present invention and can be omitted. Further, the collecting means 8 is not limited to removing the convex portion WA using the removal tape PT as in the above-described embodiment, but may also be one that removes the convex portion WA by suction holding using a suction pad or the like. It is also possible to use one that is removed and recovered by other appropriate removal methods. In addition, the energy beam irradiation means is not provided in the holding means 2 but is provided as a separate body, and the mounting tape T corresponding to the convex portion WA is irradiated with the energy rays before the wafer W is placed on the holding means 2. You may comprise as follows.
Further, in the above-described embodiment, the holding means 2 sucks and holds the mounting tape T and the ring frame RF with the outer support portion 61, and the convex portion support means 3 only supports the convex portion WA from below without being sucked and held. However, the present invention is not limited to this, and the convex portion support means 3 may be held by suction.
The wafer W may be a silicon wafer or a compound wafer.
Further, the energy beam irradiation means is not limited to the device that irradiates ultraviolet rays, and any device that irradiates an appropriate energy beam such as an electron beam to cure the adhesive sheet may be used.

DESCRIPTION OF SYMBOLS 1 Convex part removal apparatus 2 Holding means 3 Convex part support means 4 Concave part support means 5 Moving means 6 Ultraviolet lamp (energy ray irradiation means)
8 Collecting means T Mounting tape (adhesive sheet)
RF ring frame W, W 'wafer (semiconductor wafer)
WA Convex WB Concave bottom WC Concave

Claims (5)

An apparatus for removing a convex portion of a semiconductor wafer having an annular convex portion protruding in one of the thickness directions at an outer edge portion and removing the convex portion from a semiconductor wafer having a concave portion on the inner side surrounded by the convex portion,
Including holding means for holding the semiconductor wafer via an adhesive sheet affixed to the entire convex portion and the concave portion on one side of the semiconductor wafer;
The holding means has a convex portion supporting means for supporting the convex portion, a concave portion supporting means for holding the concave bottom surface, and the convex portion supporting means and the concave portion supporting means in a direction perpendicular to the surface of the semiconductor wafer. A projection removing device for a semiconductor wafer, comprising: moving means for separating the projection from the semiconductor wafer.   The apparatus for removing a convex portion of a semiconductor wafer according to claim 1, further comprising a pressing means that sandwiches a bottom area of the concave portion between the convex portion supporting means and can be driven synchronously with the moving means.   The apparatus for removing a convex portion of a semiconductor wafer according to claim 1, further comprising a collecting means for collecting the separated convex portion. The adhesive sheet is an energy ray curable adhesive sheet,
The semiconductor wafer according to any one of claims 1 to 3, further comprising energy beam irradiation means for irradiating the adhesive sheet with energy rays facing the adhesive sheet attached to the surface of the convex portion. Convex removal device. A method for removing a convex portion of a semiconductor wafer having an annular convex portion protruding in one of the thickness directions at an outer edge portion and removing the convex portion from a semiconductor wafer having a concave portion inside surrounded by the convex portion,
The convex portion is held by the convex portion support means via the adhesive sheet affixed to the entire area of the convex portion and the concave portion on one side of the semiconductor wafer, and the concave portion bottom surface is supported by the concave portion via the adhesive sheet. Hold on,
A method for removing a convex portion of a semiconductor wafer, wherein the convex portion supporting means and the concave portion supporting means are relatively moved in a direction orthogonal to the surface of the semiconductor wafer to separate the convex portion from the semiconductor wafer.

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