JP4256132B2 - Plate-shaped material transfer device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transport apparatus for transporting a plate-like object such as a semiconductor wafer.
[0002]
[Prior art]
In the semiconductor device manufacturing process, circuits such as ICs and LSIs are formed in a large number of regions arranged in a lattice pattern on the surface of a substantially disc-shaped semiconductor wafer, and each region where the circuits are formed is defined on a predetermined street. Individual semiconductor chips are manufactured by dicing along a cutting line. The semiconductor chip thus divided is packaged and widely used in electric devices such as mobile phones and personal computers. In order to improve the heat dissipation of the semiconductor chip, it is desirable to form the semiconductor chip as thin as possible. In order to reduce the size of mobile phones, smart cards, personal computers, etc. that use a large number of semiconductor elements, it is desirable to make the semiconductor elements as thin as possible.
[0003]
As a technique for reducing the thickness of the semiconductor chip, a cutting groove having a predetermined depth (a depth corresponding to the finished thickness of the semiconductor chip) is previously formed along the street by a cutting device before grinding the back surface of the semiconductor wafer. A so-called tip dicing method in which the semiconductor wafer is divided into individual semiconductor chips by grinding the back surface of the semiconductor wafer with a grinding device to expose the cut grooves is widely used.
[0004]
[Problems to be solved by the invention]
Thus, if the cutting groove is formed on the surface of the semiconductor wafer, it becomes easy to break, and the semiconductor wafer having the cutting groove is cracked during its conveyance. In order to solve such problems, a non-contact type Bernoulli pad is used as a suction holding mechanism of a transport device for transporting a semiconductor wafer on which a cutting groove is formed in a cutting device that forms a cutting groove on the surface of a semiconductor wafer. ing. However, this Bernoulli pad is configured to generate a negative pressure by allowing air to flow out along the inner surface of the conical pad and to suck and hold the semiconductor wafer by this negative pressure. When a suction action occurs and the semiconductor wafer is thin, the central portion is greatly curved and a large bending moment is generated. Therefore, particularly when a cutting groove is formed, cracking cannot be reliably prevented.
[0005]
This invention is made | formed in view of the said fact, The main technical subject is the plate-shaped material conveying apparatus which can be conveyed without cracking, even if it is a plate-shaped material in which the cutting groove was formed in the surface. It is to provide.
[0006]
[Means for Solving the Problems]
In order to solve the main technical problem, according to the present invention, a suction holding mechanism for sucking and holding a plate-like object, and a movement for moving the suction holding mechanism between a first predetermined position and a second predetermined position. A plate-like material conveying device comprising a mechanism,
The suction holding mechanism includes a plate-like object holding member, at least three non-contact type suction holders disposed on the lower surface of the central area of the plate-like object holding member, and an outer peripheral area lower surface of the plate-like object holding member. And a restricting means for restricting the horizontal movement of the plate-like object ,
The restricting means includes a long hole formed radially from the center of the plate-like object holding member, and an outer peripheral support member guided by the long hole. The object holding member has an inclined surface that inclines upward toward the center side, and a rubber sheet is disposed on the inclined surface, and the outer peripheral support member comes into contact with the upper surface of the outer peripheral portion of the plate-like object and A plate-like object conveying apparatus characterized by restricting horizontal movement of the object.
[0007]
The restricting means includes at least three outer peripheral support members that contact the upper surface of the outer periphery of the plate-like object to restrict the horizontal movement of the plate-like object, and the outer peripheral support member in the radial direction of the plate-like object holding member. And adjusting means for adjusting the movement.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of a plate-like material conveying apparatus configured according to the present invention will be described in detail with reference to the accompanying drawings.
[0009]
FIG. 1 shows a perspective view of a cutting apparatus as a dicing apparatus equipped with a plate-like material conveying apparatus constructed according to the present invention.
The cutting device in the illustrated embodiment includes a device housing 2 having a substantially rectangular parallelepiped shape. In the apparatus housing 2, a chuck table 3 for holding a workpiece is disposed so as to be movable in a direction indicated by an arrow X that is a cutting feed direction. The chuck table 3 includes a suction chuck support 31 and a suction chuck 32 mounted on the suction chuck support 31, and the suction chuck 32 is connected to a negative pressure control means (not shown). Therefore, when a disk-shaped semiconductor wafer, for example, a workpiece is placed on the placement surface, which is the surface of the suction chuck 32, and a negative pressure is applied to the suction chuck 32 by a negative pressure control means (not shown), the semiconductor The wafer is sucked and held on the suction chuck 32. The chuck table 3 is configured to be rotatable by a rotation mechanism (not shown).
[0010]
The cutting apparatus in the illustrated embodiment includes a spindle unit 4 as a cutting mechanism. The spindle unit 4 is mounted on a moving base (not shown) and is adjusted to move in a direction indicated by an arrow Y that is an indexing direction and a direction indicated by an arrow Z that is a cutting direction. A rotary spindle 42 supported and rotated by a rotary drive mechanism (not shown) is provided, and a cutting blade 43 attached to the rotary spindle 42 is provided.
[0011]
The cutting apparatus in the illustrated embodiment images the surface of the semiconductor wafer held on the surface of the suction chuck 32 constituting the chuck table 3 to detect an area to be cut by the cutting blade 43 or to form a cutting groove. An imaging mechanism 5 for confirming the state is provided. The imaging mechanism 5 is composed of optical means such as a microscope and a CCD camera. In addition, the dicing apparatus includes a display unit 6 that displays an image captured by the imaging mechanism 5.
[0012]
The cutting apparatus in the illustrated embodiment includes a cassette mounting mechanism 8 that mounts a cassette 7 that is disposed in a cassette mounting region and accommodates a semiconductor wafer that is a workpiece. Here, the cassette 7 mounted on the cassette mounting mechanism 8 will be described. The cassette 7 in the illustrated embodiment has a loading / unloading opening 71 for loading / unloading semiconductor wafers on one side, and a plurality of rack shelves 72 for loading the semiconductor wafers 9 are provided in the vertical direction. Is provided. The cassette mounting mechanism 8 for mounting the cassette 7 includes a cassette table 81 for mounting the cassette 7 and a lifting mechanism (not shown) for moving the cassette table 81 up and down. The cassette table 81 is provided with a positioning member 811 for positioning when the cassette 7 is placed on the upper surface, and a cassette sensor 812 for detecting that the cassette is placed. Further, the illustrated cutting apparatus includes a workpiece unloading mechanism 11 for unloading a semiconductor wafer 9 as a workpiece housed in a cassette 7 mounted on a cassette table 81 of the cassette mounting mechanism 8. . The workpiece unloading mechanism 11 moves forward and backward with respect to the cassette 7 mounted on the cassette mounting mechanism 8, thereby aligning the semiconductor wafer 10 accommodated in the cassette 7 in the temporary placement region. 12 to transport.
[0013]
The cutting device in the illustrated embodiment includes a first transfer device 13 for transferring the semiconductor wafer 9 carried out to the alignment mechanism 12 onto the chuck table 3, and the semiconductor wafer 9 cut on the chuck table 3. A cleaning means 14 for cleaning and a second transport device 15 for transporting the semiconductor wafer 9 cut on the chuck table 3 to the cleaning means 14 are provided. The first transport device 13 also functions as a transport device that transports the semiconductor wafer 9 cleaned by the cleaning means 14 to the alignment mechanism 12.
[0014]
Next, the first transfer device 13 will be described with reference to FIGS.
The first transport device 13 includes an L-shaped operating arm 131. One end of the L-shaped operating arm 131 is connected to the lifting means 132. The elevating means 132 is composed of, for example, an air piston, and operates the operating arm 131 in the vertical direction as indicated by an arrow 130a in FIG. The lifting / lowering means 132 connected to one end of the operating arm 131 is connected to a moving mechanism 133 including an electric motor that can rotate forward and reverse. Therefore, by driving the moving mechanism 133 in the forward direction or the reverse direction, the operating arm 131 is swung in the direction indicated by the arrow 130b in FIG. As a result, the actuating arm 131 is actuated in the horizontal plane, and a suction holding mechanism 20 (described later) mounted on the other end of the actuating arm 131 via the mounting member 135 is positioned in the horizontal plane with the positioning mechanism 12 and the positioning mechanism 12. It is moved between the chuck table 3 and the cleaning means 14.
[0015]
The suction holding mechanism 20 mounted on the other end of the operating arm 131 via a mounting member 135 includes a disk-shaped plate-like object holding member 21 as shown in FIG. A plurality of elongated holes 211 are radially formed in the outer peripheral portion of the plate-like object holding member 21 in the radial direction. The elongated hole 211 functions as a restricting means that is disposed on the lower surface of the outer peripheral area of the plate-like object holding member 21 and contacts the upper surface of the outer peripheral part of the plate-like object such as a semiconductor wafer to restrict the horizontal movement of the plate-like object. The outer peripheral support members 22 are mounted respectively. As shown in FIG. 3, the outer peripheral support member 22 includes a rectangular parallelepiped moving block 221 and a rubber sheet 222 attached to the lower surface of the moving block 221. The moving block 221 is provided with a guided projection 221a that fits into the elongated hole 211 on the upper surface, and a screw hole 221b. The outer peripheral support member 22 is formed so as to be inclined so that the lower surface thereof approaches the upper surface from the screw hole 221b side toward the guided projection 221a side. The outer peripheral support member 22 configured in this manner is adjusted by fitting the guided projection 221a into the elongated hole 211 from the lower surface side of the plate-like object holding member 21 and through the elongated hole 211 from the upper surface side of the plate-like object holding member 21. The bolt 23 is attached to the plate-like object holding member 21 by screwing into the screw hole 221b. At the time of mounting, before tightening the adjusting bolt 23, the outer peripheral supporting member 22 is moved along the long hole 211 and is positioned at a predetermined position corresponding to the outer dimension of the plate-like object such as a semiconductor wafer. Tighten. Therefore, the long hole 211 and the adjusting bolt 23 formed in the plate-like object holding member 21 function as adjusting means for moving and adjusting the outer peripheral support member 22 in the radial direction of the plate-like object holding member 21. Thus, since the outer peripheral support member 22 is configured to be movable and adjustable in the radial direction of the plate-like object holding member 21, it can correspond to the size of the plate-like object such as a semiconductor wafer to be conveyed. The outer peripheral support member 22 is preferably at least three in order to stably support the outer peripheral portion of the plate-like object.
[0016]
Three non-contact type suction holders 24 are disposed on the lower surface of the central region of the plate-like object holding member 21. As shown in FIG. 4, the non-contact type suction holder 24 includes a disk-shaped main body 241, a nozzle 242 that blows air along the lower surface at the center of the main body 241, and a nozzle 242 connected to the main body 241. The air supply passage 243 is formed. Note that a connecting portion 244 communicating with the air supply passage 243 protrudes from the upper surface of the main body 241 constituting the non-contact type suction holder 24. In the non-contact type suction holder 24, when air is ejected from the nozzle 242 along the lower surface of the main body 241 through the air supply passage 243, a negative pressure is generated in the center portion, and the plate-like object is caused by the negative pressure. However, when the plate-like object approaches, the air flowing between the lower surface of the main body 241 and the plate-like object acts as a repulsive force to prevent contact with the plate-like object and suck and hold the plate-like object in a non-contact manner. The non-contact type suction holder 24 configured as described above is mounted on the lower surface of the center region of the plate-like object holding member 21, and the connection portion 244 has a hole (not shown) provided in the plate-like object holding member 21. It is inserted and arranged. The connecting portion 244 is also inserted into a hole (not shown) provided in the mounting member 135 and is connected to a flexible pipe 136 communicated with a blown air control circuit (not shown). Note that at least three non-contact type suction holders 24 are desirable in order to suck the central region of the plate-like object widely and stably.
[0017]
The suction holding mechanism 20 in the illustrated embodiment is configured as described above, and its operation will be described with reference to FIG.
FIG. 4 shows a state where the suction holding mechanism 20 is positioned above the semiconductor wafer 9 which is a plate-like object, and blown air is supplied to each of the three non-contact type suction holders 24 and air is ejected from the nozzles 242. Thus, a negative pressure is generated at the center of each non-contact type suction holder 24. The semiconductor wafer 9 is sucked by this negative pressure. However, as described above, when the semiconductor wafer 9 approaches the non-contact type suction holder 24, air acts as a repulsive force, and contact with the semiconductor wafer 9 is prevented and contactless. Suction hold. When the semiconductor wafer 9 is sucked into the three non-contact suction holders 24 in this way, the outer peripheral edge of the semiconductor wafer 9 is a plurality of outer peripheries disposed on the lower surface of the outer peripheral area of the plate-like object holding member 21. Contact with the rubber sheet 222 constituting the support member 22, the horizontal movement of the semiconductor wafer 9 is restricted. The central portion of the semiconductor wafer 9 sucked and held by the suction holding mechanism 20 as described above is partially sucked by the three non-contact type suction holders 24, so that the center portion is greatly curved. Therefore, even if a cutting groove is formed as described later, it will not crack.
[0018]
Next, the second transport mechanism 15 will be described with reference to FIG.
The second transport mechanism 15 in the illustrated embodiment includes an operating arm 151. One end of the operating arm 151 is connected to a conventionally used reciprocating mechanism (not shown). Accordingly, a suction holding mechanism 20 (to be described later) attached to the other end of the operating arm 151 is moved between the cleaning means 14 and the chuck table 3 in a horizontal plane. The suction holding mechanism 20 attached to the other end of the operating arm 151 has substantially the same configuration as the suction holding mechanism 20 of the first transport mechanism 13 shown in FIGS. Are denoted by the same reference numerals, and description thereof is omitted. A mounting member 135 attached to the upper surface of the plate-like object holding member 21 constituting the suction holding mechanism 20 is attached to an elevating means 152 disposed at the other end of the operating arm 151. The elevating means 152 is composed of, for example, an air piston.
[0019]
The cutting apparatus equipped with the plate-shaped article conveying apparatus configured according to the present invention is configured as described above, and the operation thereof will be described below with reference to FIG.
When cutting the semiconductor wafer 9, the cassette body 71 containing the semiconductor wafer 9 is placed on the cassette table 81 of the cassette placement mechanism 8 with the loading / unloading opening 71 facing the temporary placement region side, so that the cutting work can be performed. Preparation is complete.
When an instruction to start the cutting operation is given, the workpiece unloading mechanism 11 moves forward and backward to transport the semiconductor wafer 9 accommodated in a predetermined position of the cassette body 71 to the alignment mechanism 12. The semiconductor wafer 9 transported to the alignment mechanism 12 is center-aligned here, and then transported onto the mounting surface of the suction chuck 32 constituting the chuck table 3 by the first transport device 13. That is, the lifting / lowering means 132 and the moving mechanism 133 (see FIG. 2) constituting the first transfer device 13 are operated so that the suction holding mechanism 20 is positioned above the semiconductor wafer 9 aligned by the alignment mechanism 12. As shown in FIG. 5, the semiconductor wafer 9 is sucked and held in the suction holding mechanism 20 by the operation of the blown air control circuit. Then, the raising / lowering means 132 and the moving mechanism 133 are operated to convey the semiconductor wafer 9 sucked and held by the sucking and holding mechanism 20 onto the mounting surface of the suction chuck 32 constituting the chuck table 3.
[0020]
The semiconductor wafer 9 transported onto the suction chuck 32 of the chuck table 3 by the first transport device 13 as described above is released from the suction and holding by the suction and holding mechanism 20 constituting the first transport device 13. The suction chuck 32 holds the suction. The chuck table 3 that sucks and holds the semiconductor wafer 9 in this manner is moved to a position directly below the imaging mechanism 5. When the chuck table 3 is positioned immediately below the image pickup mechanism 5, a cutting line formed on the semiconductor wafer 8 is detected by the image pickup mechanism 5, and the spindle unit 4 is moved and adjusted in the arrow Y direction as the indexing direction to adjust the precise position. Matching work is performed.
[0021]
Thereafter, while the cutting blade 43 is rotated in a predetermined direction, the chuck table 3 holding the semiconductor wafer 9 is sucked and held in a direction indicated by an arrow X that is a cutting feed direction (a direction orthogonal to the rotation axis of the cutting blade 43). By moving at the cutting feed rate, a cutting groove having a depth corresponding to the finished thickness of the semiconductor chip is formed along the street on the surface of the semiconductor wafer 8 held on the chuck table 3. That is, the cutting blade 43 is mounted on the spindle unit 4 that is moved and adjusted in the direction indicated by the arrow Y that is the indexing direction and the direction indicated by the arrow Z that is the cutting direction, and is rotationally driven. Is moved in the cutting feed direction along the lower side of the cutting blade 43, the semiconductor wafer 8 held on the chuck table 3 is cut by the cutting blade 43 along the street with a predetermined cutting depth. If the cutting groove is formed along the street on the surface of the semiconductor wafer 9 in this way, the chuck table 3 holding the semiconductor wafer 9 is first returned to the position where the semiconductor wafer 9 is sucked and held. The suction holding of the semiconductor wafer 9 is released.
[0022]
Next, the semiconductor wafer 8 which has been released from the suction on the chuck table 3 is transported to the cleaning means 14 by the second transport device 15. That is, the raising / lowering means 152 and the reciprocating mechanism (not shown) constituting the second transfer device 15 are operated to be positioned above the semiconductor wafer 8 placed on the chuck table 3 and the blown air control circuit (not shown) is operated. Thus, the semiconductor wafer 9 is sucked and held in the suction holding mechanism 20 as shown in FIG. Then, the raising / lowering means 152 and the reciprocating mechanism (not shown) are operated to transport the semiconductor wafer 9 sucked and held by the suction holding mechanism 20 to the cleaning means 14. At this time, since the semiconductor wafer 9 sucked and held by the suction holding mechanism 20 is partially sucked by the three non-contact type suction holders 24 as described above, the center part is greatly curved. Therefore, a large bending moment does not occur, and even if a cutting groove is formed on the surface, it does not crack.
[0023]
The semiconductor wafer 9 transported to the cleaning means 14 as described above is cleaned and removed by the cleaning means 14 during the cutting. The semiconductor wafer 9 cleaned by the cleaning means 14 is temporarily placed on the alignment mechanism 12 by the first transport mechanism 13. At this time, the semiconductor wafer 9 sucked and held by the suction holding mechanism 20 constituting the first transport mechanism 13 is partially sucked by the three non-contact suction holders 24 at the center as described above. Therefore, since the central portion is not greatly bent, a large bending moment does not occur, and even if a cutting groove is formed on the surface thereof, it does not crack. The semiconductor wafer 9 conveyed to the alignment mechanism 12 is stored in a predetermined position of the cassette 7 by the workpiece unloading means 11.
[0024]
【The invention's effect】
The plate-shaped material conveying apparatus according to the present invention is configured as described above, and the central portion of the plate-shaped material is partially sucked by at least three non-contact type suction holders. Therefore, a large bending moment does not occur, and even if a cutting groove is formed on the surface, it does not crack. Therefore, it is not necessary to reduce the suction force in order to avoid cracking, so that it is possible to reliably prevent the plate-like object from falling off during conveyance.
[Brief description of the drawings]
FIG. 1 is a perspective view of a cutting apparatus as a dicing apparatus equipped with a plate-shaped article conveying apparatus constructed according to the present invention.
FIG. 2 is an exploded perspective view showing a suction holding mechanism of a first transfer device as a transfer mechanism configured according to the present invention.
3 is a perspective view of an outer peripheral support member and an adjustment screw that constitute the suction holding mechanism shown in FIG. 2;
4 is a cross-sectional view of a non-contact type suction holder constituting the suction holding mechanism shown in FIG.
5 is a cross-sectional view showing a state in which a plate-like object is sucked and held by the suction holding mechanism shown in FIG. 2;
FIG. 6 is a perspective view showing a suction holding mechanism of a second transfer device as a transfer mechanism configured according to the present invention.
[Explanation of symbols]
2: Device housing 3: Chuck table 31: Adsorption chuck support base 32: Adsorption chuck 4: Spindle unit 41: Spindle housing 42: Spindle spindle 43: Cutting blade 5: Imaging mechanism 6: Display means 7: Cassette 8: Cassette placement Mechanism 81: Cassette table 9: Semiconductor wafer 11: Workpiece unloading means 12: Positioning mechanism 13: First transfer device 131: Actuating arm 132: Lifting means 133: Moving mechanism 14: Cleaning means 15: Second transfer Device 152: Lifting means 20: Suction holding mechanism 21: Plate-like object holding member 22: Outer peripheral support member 23: Adjustment bolt 24: Non-contact type suction holder

Claims (2)

In a plate-like object conveying apparatus comprising: a suction holding mechanism that sucks and holds a plate-like object; and a moving mechanism that moves the suction holding mechanism between a first predetermined position and a second predetermined position.
The suction holding mechanism includes a plate-like object holding member, at least three non-contact type suction holders disposed on the lower surface of the central area of the plate-like object holding member, and an outer peripheral area lower surface of the plate-like object holding member. And a restricting means for restricting the horizontal movement of the plate-like object ,
The restricting means includes a long hole formed radially from the center of the plate-like object holding member, and an outer peripheral support member guided by the long hole. The object holding member has an inclined surface that inclines upward toward the center side, and a rubber sheet is disposed on the inclined surface, and the outer peripheral support member comes into contact with the upper surface of the outer peripheral portion of the plate-like object and The horizontal movement of the object was restricted.
A plate-like material conveying apparatus.   The restricting means includes at least three outer peripheral support members that contact the upper surface of the outer periphery of the plate-like object to restrict the horizontal movement of the plate-like object, and the outer peripheral support member in the radial direction of the plate-like object holding member. The plate-like object conveying apparatus according to claim 1, wherein the plate-like object conveying device is configured to be adjusted.

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