JP2004349454A - Plate-shaped object transporting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plate-shaped object transporting device that can transport a plate-shaped object stuck to an adhesive sheet and attached to a frame through the adhesive sheet, by suppressing the deflections of the adhesive sheet and plate-shaped object to the utmost when transporting the plate-shaped object. <P>SOLUTION: The plate-shaped object transporting device 10 is provided with a sheet sucking section 18 which holds the adhesive sheet T by sucking, a cup 12 which covers the sheet T and plate-shaped object W, and an evacuating means 20 which evacuates the inside of the cup 12 in addition to a frame sucking section 15 which sucks the frame F. The device 10 is also provided with sensors 31, 31A, 32, and 32A which detect the position of the plate-shaped object W in the gravitational direction. The device holds the adhesive sheet T by sucking the sheet T by means of the sheet sucking section 18 and, at the same time, transports the plate-shaped object W while the deflection of the object W is suppressed to the utmost by controlling the evacuated state in the cup 12 based on the signals of the sensors 31, 31A, 32, and 32A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a device for transporting a plate-like material, and more particularly to a plate-like material transport device that suctions and transports a plate-like material such as a wafer such as a semiconductor device or an electronic component.
[0002]
[Prior art]
Conventionally, a wafer, which is a plate-like object having a semiconductor device, an electronic component, or the like formed on a front surface, is adhered on the back surface to an adhesive sheet T called a dicing sheet having an adhesive material on an upper surface as shown in FIG. In a state integrated with the frame F via T, the wafer is conveyed in the dicing apparatus, between the dicing apparatus / die bonding apparatus, and in the die bonding apparatus.
[0003]
The dicing device is a device that cuts the wafer W by putting a grinding groove in the wafer W with a grindstone called a dicing blade and divides it into individual chips.The dicing blade is a device in which fine diamond abrasive grains are electrodeposited with Ni. And an extremely thin one having a thickness of about 30 μm is used.
[0004]
The dicing blade was rotated at a high speed of 30,000 to 60,000 rpm to cut into the wafer W, and the wafer W was completely cut (full cut) or incompletely cut (half cut or semi-full cut). The full cut is a method in which the wafer W stuck on the dicing sheet is cut until the cut of about 10 μm is formed in the dicing sheet, and the half cut is a method in which the wafer W is cut to about half the thickness of the wafer W. This is a method of forming a grinding groove while leaving a thickness of about 10 μm on the wafer W.
[0005]
However, in the case of grinding with a dicing blade, since the wafer W is a highly brittle material, brittle mode processing is performed, and chipping occurs on the front and back surfaces of the wafer W, and this chipping is a factor that lowers the performance of the divided chips. I was In particular, chipping on the back surface is a troublesome problem because cracks gradually progress inside.
[0006]
As a means for solving this problem of chipping in the dicing process, a laser beam adjusted to a converging point is incident on the inside of the wafer W instead of cutting by a conventional dicing blade, and the modified region by multiphoton absorption is introduced into the wafer. There has been proposed a laser dicing apparatus for forming a wafer and dividing the wafer into individual chips.
[0007]
In these dicing apparatuses, the wafer W is generally transferred by vacuum suction of the frame F and transferred (for example, see Patent Document 1).
[0008]
After this dicing step, the wafer W is transferred to a die bonding apparatus. The die bonding device is a device that mounts the divided individual chips on the base material. First, an expanding process is performed to extend the dicing sheet to expand the interval between the individual chips, and then the individual chips are picked up. And die-bonded to the substrate.
[0009]
Also in this die bonding apparatus, the wafer W was transferred by the same transfer method.
[0010]
[Patent Document 1]
JP-A-7-169716
[Problems to be solved by the invention]
However, a conventional dicing apparatus using a dicing blade forms a dividing groove in a wafer W with an ultrathin dicing blade having a thickness of about 30 μm. With the modified region as a base point, the wafer is divided into chips by cleavage along the crystal plane of the wafer by a blue-opening action, and in both cases, the interval between the chips is extremely narrow.
[0012]
Therefore, when the diced wafer W is transported in the dicing apparatus, or from the dicing apparatus to the die bonding apparatus, or when transported in the die bonding apparatus, the dicing sheet and the wafer W attached to the dicing sheet are bent, and the chip is bent. There is a problem that the edges contact each other and chipping occurs at the edges.
[0013]
The present invention has been made in view of such circumstances, and when the plate-like material attached to the adhesive sheet and attached to the frame via the adhesive sheet is transported, the bending of the adhesive sheet and the plate-like material is performed. It is an object of the present invention to provide a plate-like object conveying device capable of conveying as little as possible.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the present invention according to claim 1, wherein the invention is applied to an adhesive sheet, and a plate-like object transport device for transporting a plate-like object attached to an annular frame via the adhesive sheet. A frame suction unit that suctions the frame, and a sheet suction unit that is disposed between the plate-shaped object and the frame suction unit and that suction-holds the adhesive sheet between the plate-shaped object and the frame. , Are provided.
[0015]
According to the first aspect of the invention, in addition to the frame suction portion for sucking the frame, the sheet suction portion for sucking and holding the adhesive sheet is provided. Only the bending at the portion where the sheet and the sheet are bonded can be achieved, so that the plate-like object can be conveyed with a small amount of bending.
[0016]
The invention according to claim 2 is a plate-like material transporting device that transports a plate-like material attached to an adhesive sheet and attached to an annular frame via the adhesive sheet, wherein the plate-like material and the adhesive sheet are used. A cover provided on the cup, a frame suction unit provided on the cup for suctioning the frame, and a pressure reducing unit for reducing the pressure in the space inside the cup, wherein the frame suction unit sucks and holds the frame, The inside is decompressed to suppress the bending of the plate-like material and the pressure-sensitive adhesive sheet.
[0017]
According to the second aspect of the invention, the frame is sucked and held by the frame suction portion, and the inside of the cup covering the plate-like object and the pressure-sensitive adhesive sheet is depressurized. Can be.
[0018]
According to a third aspect of the present invention, in the first aspect of the present invention, there is provided a cup for covering the plate-like material, and a decompression means for decompressing a space in the cup, and the frame suction section holds the frame by suction. The pressure-sensitive adhesive sheet is suction-held by the sheet suction portion, and the inside of the cup is depressurized to suppress the bending of the plate-like material.
[0019]
According to the third aspect of the present invention, the frame is sucked and held by the frame sucking section, the adhesive sheet is sucked and held by the sheet sucking section, and the inside of the cup covering the plate is depressurized. Can be suppressed.
[0020]
According to a fourth aspect of the present invention, in the second or third aspect, a sensor for detecting the position of the plate-like object in the direction of gravity, and the gravity of the plate-like object based on a detection signal from the sensor. A control unit for controlling a reduced pressure state in the cup so that the position in the direction falls within a predetermined range.
[0021]
According to the fourth aspect of the present invention, the depressurized state in the cup is controlled based on the detection signal of the sensor for detecting the position of the plate-like object in the direction of gravity. can do.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of a plate-like object transfer device according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same members are given the same numbers or symbols.
[0023]
FIG. 1 is a perspective view illustrating a form of a plate-like object conveyed by the plate-like object conveying device according to the present invention. As shown in FIG. 1, the back surface of a wafer W as a plate is attached to an adhesive sheet T having an adhesive material on an upper surface, and an annular frame F is attached to the outside of the wafer W to form a wafer W, an adhesive sheet T , And the frame F are integrated. The wafer W is transported in the dicing apparatus or the die bonding apparatus in this state.
[0024]
FIG. 2 is a side sectional view showing the configuration of the plate-like object transfer device according to the present invention. The plate-like material transfer device 10 includes a cup 12 fixed to a holder 11 by a clamper 13 and a ring-shaped frame suction unit 15 attached to the cup 12. The holder 11 is connected to an arm 16 via a diaphragm 17. Attached to.
[0025]
The suction portion 15A has a suction groove 15A formed on the lower surface thereof. The suction groove 15A communicates with a pressure reducing line 25 of the pressure reducing means 20 and is connected to a vacuum pump 21 via a regulator 23A of a control panel 22 and a valve 24A. .
[0026]
The decompression means 20 has a vacuum pump 21 and decompression lines 25, 26, and 27 connected thereto, and each decompression line is connected to a regulator 23A, 23B, 23C and a valve 24A, 24B, 24C in the control panel 22, respectively. Have been.
[0027]
The sheet suction unit 18 is attached to the inside of the frame suction unit 15. The sheet suction unit 18 is ring-shaped, and has a suction groove 18A formed on the lower surface thereof. The suction groove 18A communicates with the pressure reducing line 26 of the pressure reducing means 20 and is connected to the vacuum pump 21 via the regulator 23B and the valve 24B of the control panel 22. It is connected. The sheet suction section 18 suctions and holds the suction sheet T in a portion where the wafer W and the frame F are not attached by the suction groove 18A. The lower surface of the sheet suction portion 18 is Teflon-coated (Teflon is a product name of DuPont), so that the adhesive material of the adhesive sheet T is hardly attached.
[0028]
A suction hole 13A is formed on the lower surface of the clamper 13. The suction hole 13A communicates with a pressure reducing line 27 of the pressure reducing means 20, and is connected to a vacuum pump 21 via a regulator 23C and a valve 24C of a control panel 22, and The pressure in the chamber 12 is reduced.
[0029]
The diaphragm 17 interposed between the holder 11 and the arm 16 absorbs an extra vertical displacement of the cup 12 and an omni-directional tilt generated when the wafer W is held by sucking the frame F. Has become.
[0030]
A light-emitting element 31 that emits light horizontally in the radial direction of the wafer W and a light-receiving element 32 that receives the emitted light are mounted on the inner peripheral side of the sheet suction unit 18 at a position facing the light-emitting element 31. Further, a light emitting element 31A that emits light horizontally in the radial direction of the wafer W and an optical element that receives light emitted at a position facing the light emitting element 31A are also provided on the inner peripheral side of the mounting ring 19 attached to the outer peripheral part of the frame attracting section 15. 32A is mounted.
[0031]
The light emitting elements 31, 31A and the light receiving element 32 are arranged such that the light emitted from the light emitting element 31 is located above the upper surface of the wafer W, and the light emitted from the light emitting element 31A is located below the lower surface of the adhesive sheet T. , 32A.
[0032]
When the wafer W blocks light emitted from the light emitting element 31, the light receiving element 32 detects the light. When the adhesive sheet T blocks light emitted from the light emitting element 31 A, the light receiving element 32 A detects the light. The light emitting elements 31 and 31A and the light receiving elements 32 and 32A function as sensors for detecting the position of the wafer W in the direction of gravity.
[0033]
The light emitting elements 31 and 31A, the light receiving elements 32 and 32A, and the control panel 22 are connected to the control unit 40 and controlled respectively. The control unit 40 includes a CPU, a memory, an input / output circuit unit, and the like, and is connected to each other via a bus line.
[0034]
Next, the operation of the plate-shaped object transport device 10 configured as described above will be described. First, when holding the wafer W placed on the mounting table (not shown) by the plate-like material transfer device 10, the plate-like material transfer device 10 descends, and the frame suction unit 15 comes into contact with the frame F and stops. At this time, the inclination of the frame suction portion 15 and an extra descending stroke are absorbed by the diaphragm 17.
[0035]
Next, the pressure reducing line 25 is opened, the pressure in the suction groove 15A of the frame suction unit 15 is reduced, and the frame F is suction-held by the frame suction unit 15. Next, the decompression line 26 is opened, and a portion of the adhesive sheet T where the wafer W and the frame F are not attached is suction-held by the sheet suction portion 18. Next, the decompression line 27 is opened, and the inside of the cup 12 is slightly depressurized. In this state, the plate-like material transfer device 10 moves up, and lifts the wafer W from the mounting table.
[0036]
Since the portion of the pressure-sensitive adhesive sheet T where the wafer W and the frame F are not attached is suction-held by the sheet suction portion 18, the bending of the pressure-sensitive adhesive sheet T hardly occurs. Further, the wafer W tends to bend downward by its own weight, but since the pressure in the cup is slightly reduced, the atmospheric pressure from below and the own weight of the wafer W are suspended, and the wafer W does not bend.
[0037]
If the pressure in the cup is too weak, the wafer W bends downward by its own weight, and the lower surface of the adhesive sheet T blocks light from the light emitting element 31A, so that the light receiving element 32A detects this. The controller 40 receives the signal from the light receiving element 32A, controls the regulator 23C, and increases the pressure in the cup.
[0038]
If the pressure in the cup is too high, the wafer W bends upward, and the upper surface of the wafer W blocks the light from the light emitting element 31, so that the light receiving element 32 detects this and the pressure in the cup is reduced.
[0039]
The wafer W transported to the destination is lowered onto the mounting table at the destination, where the pressure reduction lines 25, 26, and 27 are released to the atmosphere, and the suction is released. Note that, at the time of releasing the suction, the pressure reducing lines 25 and 26 may be switched to an air source (not shown) so that a small amount of air is blown out to the suction unit. With this configuration, the suction release can be instantaneously and reliably performed.
[0040]
As described above, since the pressure-sensitive adhesive sheet T is suction-held by the sheet suction unit 18 and the pressure in the cup 12 is appropriately controlled, the wafer W is transferred while the bending of the wafer W is kept within a predetermined value. Is done. Therefore, when the laser beam is condensed on the inside of the wafer and the wafer W on which the laser dicing for forming the modified area is carried is conveyed, the wafer W may be cut at an inappropriate portion before the expansion. Is prevented. Also, in the case of individually divided wafers W, contact between chips is suppressed as much as possible, and chipping at chip edges can be prevented.
[0041]
FIG. 3 to FIG. 6 show another embodiment of the plate-like object transfer device 10 of the present invention. 3 to 6, the description of common parts with FIG. 2 will be omitted. 3 differs from the embodiment of FIG. 2 in that a sensor 30 for detecting the position of the wafer W in the direction of gravity is provided above the center of the wafer W in the cup 12.
[0042]
As shown in FIG. 3, a sensor 30 for detecting the upper surface of the wafer W is attached to the tip of the clamper 14. Although the sensor 30 is a capacitance type sensor, various known sensors such as an optical interference type optical sensor are not limited to the capacitance type sensor.
[0043]
The controller 40 controls the regulator 23C of the decompression line 27 so that the distance between the sensor 30 and the upper surface of the wafer W is within a predetermined range, based on the signal from the sensor 30, and determines the degree of decompression in the cup 12. Control.
[0044]
FIG. 4 is for transporting a wafer W that is relatively hard to bend, and is configured to adsorb and hold the adhesive sheet portion on which the wafer W and the frame F are not attached by the sheet adsorbing section 18. In the case of the plate-like object transfer device 10, since the adhesive sheet portion does not bend, a bending moment is hardly applied to the wafer W. Therefore, the bending of the wafer W can be suppressed with a simple configuration.
[0045]
In the case of FIG. 4, the cup 12 is not particularly required, and may be any member that supports the frame suction unit 15 and the sheet suction unit 18, and its shape is not particularly limited.
[0046]
FIG. 5 shows a method in which the wafer W and the pressure-sensitive adhesive sheet portion are not bent by the pressure reduction in the cup 12 without the sheet suction portion 18. In this case, the pressure reduction control in the cup 12 is not performed, and the set value of the regulator 23C is switched to an appropriate value according to the type of the wafer W based on the experimental value obtained in advance for each type of the wafer W.
[0047]
FIG. 6 shows a configuration in which a sensor 30 for detecting the upper surface of the wafer W is added to the configuration of FIG. 5, and the control unit 40 determines the distance between the sensor 30 and the upper surface of the wafer W by a signal from the sensor 30. The pressure in the cup 12 is controlled by controlling the regulator 23C of the pressure reducing line 27 so as to fall within the range.
[0048]
As described above, also in the embodiment shown in FIGS. 3 to 6, the bending of the wafer W during transfer can be suppressed.
[0049]
【The invention's effect】
As described above, according to the plate-like object conveying device of the present invention, since the sheet adsorbing section that adsorbs and holds the adhesive sheet is provided in addition to the frame adsorbing section that adsorbs the frame, the bending only at the adhesive sheet section is performed. Is eliminated, and only the bending at the portion where the plate-like material and the adhesive sheet are bonded to each other can be carried with a reduced amount of bending of the plate-like material.
[0050]
In addition, since the frame is sucked and held by the frame suction portion and the pressure inside the cup covering the plate-like object and the pressure-sensitive adhesive sheet is reduced, the bending of the plate-like material and the pressure-sensitive adhesive sheet can be suppressed.
[0051]
Further, the frame is sucked and held by the frame sucking section, the pressure-sensitive adhesive sheet is sucked and held by the sheet sucking section, and the pressure inside the cup covering the plate is reduced, so that the bending of the plate can be suppressed.
[0052]
In addition, since the pressure-reduced state in the cup is controlled based on the detection signal of the sensor that detects the position of the plate-like object in the direction of gravity, the plate-like object can be conveyed with the bending thereof being suppressed as much as possible.
[0053]
As described above, since the wafer W is transported in a state where the deflection of the wafer W is kept within a predetermined value, laser dicing is performed in which laser light is focused inside the wafer and a modified region is formed inside. Also, when the wafer W is transferred, the wafer W is prevented from being cut at an inappropriate portion before being expanded. Also, in the case of individually divided wafers W, contact between the chips is suppressed as much as possible, and chipping is prevented from occurring at the edge portions of the chips.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a wafer mounted on a frame. FIG. 2 is a conceptual configuration diagram of a plate-like object transfer device according to an embodiment of the present invention. FIG. 3 is a plate-like shape according to another embodiment of the present invention. FIG. 4 is a conceptual configuration diagram of a plate-like material transfer device according to another embodiment of the present invention. FIG. 5 is a conceptual configuration diagram of a plate-like material transfer device according to another embodiment of the present invention. FIG. 6 is a conceptual configuration diagram of a plate-like object transfer device according to another embodiment of the present invention.
DESCRIPTION OF SYMBOLS 10 ... Plate-like material conveyance apparatus, 12 ... Cup, 15 ... Frame suction part, 18 ... Sheet suction part, 20 ... Pressure reduction means, 30 ... Sensor, 40 ... Control part, T ... Adhesive sheet, W ... Wafer (plate-like thing) )

Claims (4)

In a plate-like object conveying device that is attached to an adhesive sheet and conveys a plate-like object attached to an annular frame via the adhesive sheet,
A frame suction unit for suctioning the frame,
A sheet suction unit that is disposed between the plate-shaped object and the frame suction unit and that suction-holds the pressure-sensitive adhesive sheet between the plate-shaped object and the frame. Conveyance device. In a plate-like object conveying device that is attached to an adhesive sheet and conveys a plate-like object attached to an annular frame via the adhesive sheet,
The plate-like object, and a cup covering the adhesive sheet,
A frame suction unit provided on the cup and suctioning the frame;
Pressure reducing means for reducing the pressure in the space in the cup,
The plate-like object conveyance device, wherein the frame suction unit holds the frame by suction and reduces the pressure in the cup to suppress the bending of the plate-like object and the adhesive sheet. A cup covering the plate-like object,
Pressure reducing means for reducing the pressure in the space in the cup,
The frame suction unit holds the frame by suction, the sheet suction unit suctions and holds the pressure-sensitive adhesive sheet, and suppresses the bending of the plate-like object by reducing the pressure in the cup. 2. The plate-like object transfer device according to 1. A sensor for detecting the position of the plate-like object in the direction of gravity,
A control unit that controls a reduced pressure state in the cup such that the position of the plate-like object in the direction of gravity falls within a predetermined range based on the detection signal of the sensor, The plate-like object conveyance device according to claim 2 or 3.

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