JPH10177975A - Dicing blade, dicing method thereby, and manufacturing method of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a semiconductor wafer to be diced along narrow dicing lines by a method wherein abrasive particles which contain fullerene particles are provided to edges provided to a rotary hub along is periphery. SOLUTION: A rotary dicing blade 20 is composed of a rotary hub 21 which is formed of Al alloy or the like, and provided with a hole 21a where the drive shaft of a drive device is inserted and a cutting edge 22 which is formed of nickel or nickel alloy and provided along the periphery of the rotary hub 21. A film 23 of nickel or nickel alloy which contains fullerene C 60 particles is formed on the surface of the cutting edge 22. The cutting edge 22 is typically 1.2mm or so in length and 60μm or so in edge width. Fullerene is an allotrope of carbon, and fullerene C 60 is composed of sixty carbon atoms which are mutually bonded together by covalent bonding alternately forming pentagons and hexagons, so that the C 60 has such a structure that it looks like a hollow reticulate soccer ball.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to the manufacture of semiconductor devices, and more particularly to a rotary dicing blade, a method of dicing a wafer using the rotary dicing blade, and a method of manufacturing a semiconductor device. In manufacturing a semiconductor device, a large number of semiconductor device patterns are formed on a semiconductor wafer by a wafer process. After the formation of the semiconductor device patterns, the semiconductor wafer is divided into individual semiconductor chips by a so-called dicing process. In such a dicing process, a rotary dicing blade constituting a part of a dicing apparatus cuts a semiconductor wafer along a predetermined dicing line.

In the manufacture of semiconductor devices, it is required to reduce the width of the dicing line as much as possible in a dicing process in order to reduce the price of each semiconductor device as much as possible. By reducing the width of the dicing line, the number of semiconductor chips obtained from one wafer increases. In order to increase the manufacturing throughput of the semiconductor device, it is preferable to maximize the speed at which the rotating blade is moved along the dicing line, that is, the dicing feed speed.

[0003]

2. Description of the Related Art FIGS. 7A and 7B are a front view and a side view showing the structure of a rotary dicing blade used in a conventional dicing process, and FIG. 7C is an enlarged view. It is. Referring to FIGS. 7A and 7B, the rotary dicing blade 10 includes a hub 11 made of an Al alloy or the like having a hole 12 for receiving a drive shaft (not shown) of a dicing device, and the hub 11. 11 is formed along the outer peripheral portion of Ni or Ni alloy, and as shown in the enlarged view of FIG.
Diamond granules are buried on electrode 3 by electrodeposition.

FIG. 8 shows a Si wafer 15 cut by the rotary dicing blade 10 shown in FIGS. Referring to FIG. 8, a large number of semiconductor chips 16 are defined on a wafer 15 by a large number of dicing lines 17 extending in a grid pattern, and the rotating dicing blade 10 divides the wafer 15 into the dicing. Line 1
Cut along each of 7. Each semiconductor chip 16 includes a number of semiconductor elements (not shown) to form an integrated circuit.

FIG. 9 shows an example of cutting the Si wafer 15 by the rotary dicing blade 10 shown in FIGS. 7A to 7C along the dicing line 17 shown in FIG. FIG.
As shown in FIG.
m in the dicing line 17 and a dicing groove 17 having a width approximately corresponding to the width W of the cutting edge 13.
A is formed. The cutting edge of the cutting edge 13 typically has a cutting edge length of about 700 μm and a cutting edge width W of about 60 μm,
Diamond abrasive grains 14 having a particle size of 4 to 8 μm are electrodeposited on the outer peripheral surface and side surfaces of the cutting edge.

[0006]

As can be seen from FIG. 9, the dicing groove 17A formed by such a rotary dicing blade 10 is generally defined by an irregular side wall surface 18. The unevenness Δ is called chipping. In order to minimize the width w of the dicing line 17, it is necessary to minimize the chipping Δ. However, when dicing is performed with the rotary dicing blade 10 having the above configuration, the size of the chipping Δ is reduced to 30 μm or less. In order to suppress, the dicing feed speed, that is, the semiconductor wafer 15 of the rotary dicing blade 10 is controlled.
Is required to be suppressed to a low speed of typically 100 mm / sec or less. However, when the dicing feed speed is reduced in this way, the manufacturing throughput of the semiconductor device is inevitably reduced. Also, when dicing at such a low speed for a long time,
The life of the rotary dicing blade 10 is also 6 inch diameter S
The limit is about 50,000 lines for i-wafer.

On the other hand, in the configuration shown in FIG. 9, when the width w of the dicing line 17 is 90 μm, the edge length L of the rotary dicing blade 10 must be reduced to about 500 μm, and the edge width W is also reduced. It needs to be reduced to about 45 μm. In order to suppress the chipping Δ to 20 μm or less in such a configuration, the dicing feed speed needs to be suppressed to about 60 mm / sec, and the manufacturing throughput of the semiconductor device is further reduced. Also,
The life of the rotary dicing blade 10 is also reduced to about 30,000 lines when dicing a 6-inch diameter Si wafer.

In order to extend the life, the blade edge length L is set to 7
It is conceivable to increase the diameter up to about 00 μm, but with such a rotary dicing blade having a large blade edge length L, the blade edge is easily bent, so that the rotation speed cannot be increased. For example, the rotation speed needs to be suppressed to about 70 mm / sec or less. In addition, such specially configured rotating blades are expensive.

Accordingly, the present invention provides a method for manufacturing a new and useful semiconductor device, a dicing method,
And to provide a dicing apparatus. A more specific object of the present invention is a dicing blade that can be applied to dicing along a narrow dicing line and can perform dicing efficiently, a dicing method using such a dicing apparatus, and a semiconductor using such a dicing method. An object of the present invention is to provide a method for manufacturing a device.

[0010]

The present invention solves the above problems,
As described in claim 1, in a dicing blade including a rotating hub, a blade provided along an outer periphery of the hub, and abrasive grains provided on the blade, the abrasive grains include fullerene particles. Or a dicing blade according to claim 1, wherein the abrasive grains are substantially composed of fullerene only.
As described in the above, the abrasive grains are composed of a mixture of fullerene and diamond abrasives, the dicing blade according to claim 1, or as described in claim 4, the abrasive grains are fullerene and A dicing blade according to claim 1, wherein the dicing blade is made of a mixture with CBN, or as set forth in claim 5, provided in a method for dicing a wafer, provided along a rotating hub and an outer periphery of the hub. 7. A dicing method comprising a blade and abrasive grains provided on the blade, wherein the abrasive grains include a step of cutting the wafer with a dicing blade containing fullerene particles.
The abrasive grains are substantially composed of fullerene only, as described in claim 5, or the abrasive grains are fullerene and diamond abrasive grains, as described in claim 7, The dicing method according to claim 5, comprising a mixture of
Alternatively, as set forth in claim 8, the abrasive grains are composed of a mixture of fullerene and CBN, and the dicing method of a semiconductor substrate according to claim 5, or as set forth in claim 9, In the method for manufacturing a semiconductor device including a step, the dicing step includes a rotating hub, a blade provided along an outer periphery of the hub, and abrasive grains provided on the blade, wherein the abrasive grains are fullerene particles. By a dicing blade containing, by a method of manufacturing a semiconductor device, comprising a step of cutting the semiconductor substrate, or as described in claim 10, the abrasive grains are substantially composed of only fullerene The method of manufacturing a semiconductor device according to claim 9, or as described in claim 11, wherein the abrasive grains are formed by fullerene and diamond polishing. The method according to claim 9, wherein the abrasive grains comprise a mixture of fullerene and CBN. 13. The method of manufacturing a semiconductor device according to claim 9, wherein the abrasive grains comprise a mixture of fullerene and CBN. The problem is solved by the method of manufacturing a semiconductor device according to item 9. [Function] According to the present invention, by using fullerene as abrasive grains of a rotary dicing blade, it is possible to suppress chipping without lowering the dicing feed speed when dicing a wafer using the rotary dicing blade. it can.

FIG. 1 shows the molecular structure of fullerene C60. Fullerenes were identified in 1985 as C
In C60, as shown in FIG. 1, 60 C atoms 1 indicated by white circles and black circles are mutually bonded by a covalent bond 2 to form hexagons and pentagons which are alternately repeated, as shown in FIG. As a result, the C60 molecule has a structure resembling a hollow mesh soccer ball. One molecule of C60 has a size of 7 °, and is considered to have a higher hardness than diamond according to molecular theory. It is known that the fullerene has a stable C70 structure in addition to the C60 structure. In addition, a higher fullerene such as C960 or a heterofullerene incorporating a metal atom may be used.

Therefore, in the present invention, the above fullerene molecules are used as abrasive grains of the rotary dicing blade instead of the conventional diamond. By using fullerene molecules, chipping of the semiconductor wafer can be significantly reduced. Therefore, the dicing width on the semiconductor wafer can be reduced, and the number of semiconductor chips obtained from one wafer can be increased. Further, it is not necessary to reduce the blade feed speed during dicing to suppress the chipping, and the manufacturing throughput of the semiconductor device does not decrease even if the dicing width is reduced. Further, the life of the rotary dicing blade is also improved.

[0013]

FIG. 2 shows the structure of a rotary dicing blade 20 according to a first embodiment of the present invention. Referring to FIG. 2, a rotary dicing blade 20 includes a rotary hub 21 made of an Al alloy or the like having a hole 21a for receiving a drive shaft of a driving device, and nickel or a nickel alloy formed along the outer periphery of the rotary hub. Cutting edge 22 consisting of etc.
The surface of the cutting edge 22 has fullerene C60
The nickel or nickel alloy film 23 containing the particles of the above is formed. The cutting edge 22 is typically about 1.2 mm
And a blade width W of about 60 μm.

FIG. 3 shows the rotary dicing blade 2 of FIG.
0 shows a part of the manufacturing process. Referring to FIG. 3, water 25 is placed in a water tank 26 on which a base 27 made of metal such as Al is installed.
Is satisfied, and fullerene particles 24 having a particle size of several to several nanometers are suspended in the water 25. Further, the table 2
The rotary dicing blade 20 is placed flat on the 7 while holding the cutting edge 22.

A carbon electrode 28 is buried in the base 27, and by applying a negative voltage to the carbon electrode 28, the positively charged fullerene particles 24 are electrically conducted in the water toward the hub 21. Moved by electrophoresis,
2 is deposited. In this step, it is preferable to form a mask 21A on the hub 21 so that only the cutting edge 22 is exposed. Fullerene particles 2 on the cutting edge 22
The deposition density of No. 4 can be controlled by adjusting the concentration of the fullerene particles 24 in the water 25.

FIG. 4A shows a semi-finished product of the rotary dicing blade 20 obtained in the step of FIG. On the semi-finished product of FIG. 4 (A), in the step of FIG. 4 (B), a metal film 29 made of Ni or a Ni alloy is vapor-phased so as to cover the fullerene particles deposited on the cutting edge 22. 4 (C), a resin protective film 30 such as a so-called metal bond is formed on the metal film 29 in the step of FIG.

FIG. 5 is a schematic view of the process using the rotary dicing blade 20 obtained in the steps shown in FIGS. 3 and 4A to 4C.
It shows the maximum chipping amount Δ when dicing the i-wafer. However, the results in FIG. 5 are for the case where the cutting edge width W of the rotary dicing blade 20 is 60 μm, the dicing feed speed is 100 mm / sec, and the Si wafer is diced along a dicing line having a width of 90 μm. is there. As described above with reference to FIG. 9, the chipping amount Δ is for one side of the dicing groove 17A.

Referring to FIG. 5, it can be seen that the maximum chipping amount Δ can be suppressed to 15 μm or less by using fullerene particles having a particle size of several tens of degrees as abrasive grains.
On the other hand, when the Si substrate is polished under the same conditions by a rotary dicing blade using diamond having a particle diameter of 4 to 8 μm as the abrasive, the maximum chipping amount Δ is 2
Reaches 5 μm. Also, when diamond having a particle size of 4 to 6 μm is used as an abrasive, the maximum chipping amount is 2 μm.
Reaches 0 μm.

The above results indicate that the rotary dicing blade 2
0 indicates that by using fullerene particles as abrasive grains, it is possible to suppress the chipping amount Δ without having to suppress the dicing feed speed even when the dicing width is narrow. Further, in the rotary dicing blade 20, there is no need to reduce the dicing feed speed, so that the life of the dicing blade is greatly extended. For example, in the case of a dicing blade having a blade edge width W of 45 μm,
Although dicing of 50,000 lines or more is possible, this is a value which has been conventionally achieved with a dicing blade having a cutting edge width of 60 μm.

FIG. 5 shows that the abrasive grains are obtained by mixing CBN (carbon BN) particles having a particle size of 4 to 6 μm with fullerene particles having a particle size of several tens of mm in a ratio of about 1: 1; The case where diamond particles having a particle size of 4 to 8 μm are mixed with the fullerene particles in the same ratio of about 1: 1 will be shown in comparison. Also in these cases, it can be seen that the maximum chipping amount Δ decreases to about 15 μm or less.

In the present invention, the fullerene particles are not limited to C60 shown in FIG.
Other fullerene particles such as 0 or heterofullerene particles containing a metal element can also be used. FIG.
Rotary dicing blade 40 according to a second embodiment of the present invention
Is shown. However, in FIG. 6, the parts described above are denoted by the same reference numerals, and description thereof will be omitted.

Referring to FIG. 6, in the rotary dicing blade 40, the metal film 23 including the fullerene abrasive grains is
It is formed not on the entire exposed surface of the cutting edge 22, but only on the tip. Even in this case, the polishing characteristics shown in FIG. 5 can be obtained. As described above, the present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to such embodiments, and various modifications and changes can be made without departing from the spirit of the appended claims.

[0023]

According to the features of the present invention, chipping of a semiconductor wafer can be significantly reduced by using fullerene molecules as abrasive grains of a rotary dicing blade for cutting a wafer. Therefore, the dicing width on the semiconductor wafer can be reduced, and the number of semiconductor chips obtained from one wafer can be increased. Further, it is not necessary to reduce the blade feed speed during dicing to suppress the chipping, and the manufacturing throughput of the semiconductor device does not decrease even if the dicing width is reduced. Further, the life of the rotary dicing blade is also improved.

[Brief description of the drawings]

FIG. 1 is a view showing the molecular structure of fullerene C60.

FIG. 2 is a view showing a configuration of a rotary dicing blade according to a first embodiment of the present invention.

FIG. 3 is a diagram illustrating a process of attaching fullerene particles onto the rotary dicing blade of FIG. 2;

FIGS. 4 (A) to 4 (C) are diagrams illustrating a manufacturing process of the rotary dicing blade of FIG. 2;

5 is a diagram showing the amount of chipping when dicing an Si wafer using the rotary dicing blade of FIG. 2 in comparison with the case where a conventional rotary dicing blade is used.

FIG. 6 is a view illustrating a configuration of a rotary dicing blade according to a second embodiment of the present invention.

FIGS. 7A to 7C are diagrams showing a configuration of a conventional rotary dicing blade.

FIG. 8 is a diagram illustrating dicing along a dicing line of a semiconductor wafer.

9 is a diagram illustrating a problem of chipping that occurs in the conventional dicing process of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 C atom 2 Covalent bond 10,20 Rotating dicing blade 11,21 Hub 12,21a Shaft hole 13,22 Cutting edge 14,23 Metal film and abrasive grain 15 Si wafer 16 Semiconductor chip 17 Dicing line 17A Dicing groove 18 Chipping 24 Fullerene particles 25 water 26 water tank 27 units 28 carbon electrode 29 metal film 30 resin film

Claims (12)

[Claims] 1. A dicing blade comprising a rotary hub, a blade provided along the outer periphery of the hub, and abrasive grains provided on the blade, wherein the abrasive grains include fullerene particles. Dicing blade. 2. The dicing blade according to claim 1, wherein the abrasive grains are substantially composed of only fullerene. 3. The dicing blade according to claim 1, wherein said abrasive grains comprise fullerene and diamond abrasive grains. 4. The dicing blade according to claim 1, wherein said abrasive grains comprise fullerene and CBN. 5. A method of dicing a wafer, comprising: a rotating hub; a blade provided along an outer periphery of the hub;
A dicing method comprising: a step of cutting the wafer by a dicing blade including abrasive grains provided on the blade, wherein the abrasive grains include fullerene particles. 6. The dicing method according to claim 5, wherein the abrasive grains are substantially composed of fullerene only. 7. The dicing method according to claim 5, wherein said abrasive grains comprise fullerene and diamond abrasive grains. 8. The dicing method according to claim 5, wherein said abrasive grains comprise fullerene and CBN. 9. A method for manufacturing a semiconductor device including a dicing step of a semiconductor substrate, wherein the dicing step comprises: a rotating hub; a blade provided along an outer periphery of the hub; and abrasive grains provided on the blade. A method of manufacturing a semiconductor device, comprising a step of cutting the semiconductor substrate with a dicing blade containing fullerene particles as the abrasive grains. 10. The method of manufacturing a semiconductor device according to claim 9, wherein said abrasive grains are substantially composed of only fullerene. 11. The method according to claim 9, wherein the abrasive grains are made of fullerene and diamond abrasive grains. 12. The method according to claim 9, wherein the abrasive grains are made of fullerene and CBN.