JP2005136228A - Method for dicing semiconductor substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for dicing a semiconductor substrate for easily removing chipping(default) to be generated on the back face of a semiconductor substrate on which a plurality of semiconductor elements are formed in dicing the semiconductor substrate in order to prevent the reattachment of such chipping. <P>SOLUTION: This method for dicing a substrate is configured to cut the substrate on which a plurality of elements are formed, and to separate the substrate into individual element chips. The method is provided with a process to attach the back face of the substrate to a film base material; a process to cut the substrate from the surface by a cutting blade, and to cut and divided the substrate into individual element chips on the film base material; a process to enlarge a gap between the cut and divided individual element chips by extending the film base material; and a process to wash the gap area between the individual semiconductor chips, and to remove chipping generated on the backside of the semiconductor substrate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a semiconductor substrate dicing method in which a substrate on which a plurality of semiconductor elements are formed is cut and separated into individual semiconductor chips.

Conventionally, various semiconductor elements are manufactured through a process such as forming a plurality of semiconductor elements simultaneously on a semiconductor substrate (hereinafter referred to as a semiconductor wafer), separating each element into chips in a dicing process, and enclosing the package. .
Conventionally, as shown in FIG. 7, the semiconductor wafer 1 is adhered and fixed to the center portion of a synthetic resin dicing tape 11 of the frame 10, and the frame 10 is placed and fixed on a chuck table on a dicing apparatus. After the positioning by the apparatus, the tip portion as shown in FIG. 5 is diced along the street of the semiconductor wafer by the rotary blade 7 having a rectangular cross section and cut completely or with a small amount of uncut.

When the semiconductor wafer 1 is diced as described above, as shown in FIG. 6, a crack 9 is generated from the vicinity of the cut groove 8, and chipping (missing) occurs. As for the cracks and chipping, those peeled off at the time of picking up the pellet cause contamination as particles. Therefore, as a conventional example for preventing such redeposition of chipping, for example, when dicing as described in Patent Document 1, the adhesive force of an ultraviolet curable adhesive on the line in advance is changed to ultraviolet UV or A method of cutting with a blade while reducing by irradiation with heat rays has been disclosed.
Japanese Patent Laid-Open No. 9-17752

However, the above-described conventional example has a problem that the configuration of the apparatus becomes complicated when a material that hardly transmits ultraviolet rays UV or heat rays, such as a Si wafer, is used for a semiconductor substrate on which a plurality of semiconductor elements are formed. .
Therefore, the present invention solves such a problem, and when chipping a semiconductor substrate on which a plurality of semiconductor elements are formed, the chipping (missing) generated on the back surface of the semiconductor substrate can be easily removed. An object of the present invention is to provide a semiconductor substrate dicing method capable of preventing reattachment.

The present invention provides a semiconductor substrate dicing method configured as follows.
That is, the semiconductor substrate dicing method of the present invention is a semiconductor substrate dicing method in which a substrate on which a plurality of semiconductor elements are formed is cut and separated into individual semiconductor chips. The step of adhering, the step of cutting the substrate from the surface with a cutting blade and cutting the substrate into individual semiconductor chips on the film base, and the individual semiconductor chips cut out by stretching the film base The method includes a step of enlarging a gap between the semiconductor chips, and a step of cleaning a gap region between the individual semiconductor chips to remove chipping generated on the back surface of the semiconductor substrate.
Further, the dicing method of the semiconductor substrate of the present invention cures the adhesive layer of the film base between the step of cutting into the individual semiconductor chips and the step of expanding the gap between the individual semiconductor chips. And it can be set as the structure which has the process of reducing adhesive force.
Further, the semiconductor substrate dicing method of the present invention is a semiconductor substrate dicing method in which a substrate on which a plurality of semiconductor elements are formed is cut and separated into individual semiconductor chips. The step of adhering to the adhesive layer, the step of cutting the substrate from the surface with a cutting blade, cutting into individual semiconductor chips on the film base, and the cutting by stretching the film base A step of expanding the gap between the individual semiconductor chips, a step of curing the adhesive layer of the film base material to reduce the adhesive force, and cleaning a gap region between the individual semiconductor chips, And a step of removing chipping generated on the back surface.
Further, the dicing method of the semiconductor substrate of the present invention uses an ultraviolet curable adhesive for the adhesive layer of the film base material and irradiates the adhesive layer with ultraviolet light in the step of reducing the adhesive force. It can be configured to cure.
Moreover, the semiconductor substrate dicing method of the present invention can irradiate the ultraviolet light only on the dicing street.
Further, the semiconductor substrate dicing method of the present invention can adopt a configuration in which the irradiation to the dicing street is performed with respect to the interval between the semiconductor chips after the step of expanding the gap between the individual semiconductor chips.
In the semiconductor substrate dicing method according to the present invention, after the step of cleaning the gap region between the individual semiconductor chips and removing the chipping generated on the back surface of the semiconductor substrate, ultraviolet light is irradiated from the back surface side of the substrate. And it can be set as the structure which has the process of hardening the said ultraviolet curing adhesive, and reducing adhesive force.

  According to the present invention, at the time of dicing a semiconductor substrate on which a plurality of semiconductor elements are formed, chipping (missing) generated on the back surface of the semiconductor substrate can be easily removed, and chipping reattachment can be prevented. A semiconductor substrate dicing method can be realized.

  The best mode for carrying out the present invention will be described by the following examples.

[Example 1]
FIG. 1 is a process diagram showing an outline of a dicing method in Embodiment 1 of the present invention.
The dicing method of this embodiment will be described with reference to FIG. 1. First, in the first step shown in FIG. 1 (1), a synthetic resin dicing tape is attached to the entire back surface of the semiconductor wafer 1 to be cut. . A Si wafer is used as the semiconductor wafer 1 here.
In the dicing tape of this example, the adhesive 2 having a predetermined adhesive force is applied to the surface of the film-like substrate 3, and the adhesive layer side is adhered to the wafer back side. In this embodiment, the thickness of the semiconductor wafer is about 600 μm, and D-105V manufactured by Lintec Corporation is used as the dicing tape. The thickness of the adhesive is 10 μm, and the thickness of the film serving as the substrate is 80 μm.

  Next, in the 2nd process shown to (2) of FIG. 1, product number NBC-ZB2030 by DISCO Corporation is used as a dicing blade for dicing. FIG. 2 shows the relationship between the semiconductor wafer 1 and the dicing tape 11 diced by the dicing blade in this step. Here, the thickness of the surface layer of the adhesive of the dicing tape 11 is 10 μm as described above, and the thickness of the film is 80 μm. Therefore, the thickness of the entire adhesive sheet is 90 μm. Here, the tip of the dicing blade is cut to 40 μm in the dicing tape. Thereby, the dicing tape can be left uncut by 40 μm. Since the dicing blade cuts the dicing tape by 40 μm further below the adhesive layer, the tapered portion near the tip of the dicing blade does not touch the cut portion of the semiconductor wafer, and the cut surface of the semiconductor wafer. Can be flat. The dicing speed is 5 mm / s. When dicing is performed, the back surface chipping 4 occurs due to chipping of the back surface of the substrate due to chip vibration during cutting or the like.

Next, radial stretching is performed in the third step (3) of FIG. Thereby, the back surface chipping 4 hidden in the shadow of the chip is separated from the chip and appears on the surface of the dicing tape.
Subsequently, in the fourth step of (4) in FIG. 1, the back surface chipping 4 can be easily removed by removing the back surface chipping 4 in the vicinity of the street by air blowing or running water cleaning 6.
Finally, in the fifth step of FIG. 1 (5), the chip is picked up. After removing the back surface chipping in this way, the back surface chipping 4 is contaminated as particles by picking up the chip. Can be prevented.

[Example 2]
FIG. 3 is a process diagram showing an outline of the dicing method in Embodiment 2 of the present invention. In this example, a UV irradiating type in which a step of irradiating ultraviolet rays from the back surface of the wafer is provided between the second step and the third step of the dicing method in the above-described first embodiment, and the back side of the wafer is adhered to the dicing tape The adhesive strength of the adhesive is reduced, and the back surface chipping 4 is easily removed by air blowing or running water cleaning. In the first step shown in FIG. 3 (1), the UV curing type adhesive is used as the adhesive 2 having a predetermined adhesive force on the surface of the film-like substrate 3 in the dicing tape. The difference is that it is applied and a third step of irradiating ultraviolet rays from the back surface of the wafer is added, and the others are basically the same as in the first embodiment.

First, in the first step shown in FIG. 3A, a synthetic resin dicing tape is attached to the entire back surface of the semiconductor wafer 1 to be cut. A Si wafer is used as the semiconductor wafer 1 here.
In the dicing tape of this embodiment, the surface of the film-like substrate 3 is coated with an adhesive 2 having an ultraviolet curing type predetermined adhesive force, and the adhesive layer side is adhered to the wafer back side. ing. In this embodiment, the thickness of the semiconductor wafer is about 600 μm, and D-105V manufactured by Lintec Corporation is used as the dicing tape. The thickness of the adhesive is 10 μm, and the thickness of the film serving as the substrate is 80 μm. Next, in the second step shown in (2) of FIG. 3, a product model number NBC-ZB2030 manufactured by DISCO Corporation is used as a dicing blade for dicing. FIG. 2 shows the relationship between the semiconductor wafer 1 and the dicing tape 11 diced by the dicing blade in this step. The thickness of the surface layer of the adhesive of the dicing tape 11 here is 10 μm as described above, and the thickness of the film is, for example, 80 μm. Therefore, the thickness of the entire adhesive sheet is 90 μm. Here, the tip of the dicing blade is cut into a dicing tape to 40 μm. Thereby, the dicing tape can be left uncut by 40 μm. Since the dicing blade cuts the dicing tape by 40 μm further below the adhesive layer, the tapered portion near the tip of the dicing blade does not touch the cut portion of the semiconductor wafer, and the cut surface of the semiconductor wafer. Can be flat. The dicing speed is 5 mm / s. When dicing is performed, the back surface chipping 4 occurs due to chipping of the back surface of the substrate due to chip vibration during cutting or the like.

Next, in the third step shown in FIG. 3 (3), the back surface of the wafer is irradiated with ultraviolet rays by an ultraviolet irradiation device. The light intensity of the ultraviolet light 5 to be irradiated is 500 mj / cm ² . The irradiated adhesive is cured and its adhesive strength is reduced or eliminated. At this time, the adhesive strength of the dicing tape is 400 g / 25 mm before irradiation with ultraviolet rays, and decreases to about 40 g / 25 mm after irradiation with ultraviolet rays. The adhesive force is an adhesive force to the Si wafer.

Next, radial stretching is performed in the fourth step (4) of FIG. Thereby, the back surface chipping 4 hidden in the shadow of the chip is separated from the chip and appears on the surface of the dicing tape.
Subsequently, in the fifth step of (5) in FIG. 3, the back surface chipping 4 can be easily removed by removing the back surface chipping 4 in the vicinity of the street by air blowing or running water cleaning 6.
Finally, in the sixth step (6) in FIG. 3, the chip is picked up. According to the present embodiment, when the back surface chipping in the vicinity of the street is removed by air blow or running water cleaning in the fifth step (5) of FIG. Since the back surface chipping and the peel strength of the tape are reduced by curing, the back surface chipping 4 can be easily removed.

[Example 3]
FIG. 4 is a process diagram showing an outline of the dicing method in Embodiment 3 of the present invention.
The dicing method of this embodiment will be described with reference to FIG. 4. First, in the first step shown in FIG. 4 (1), a dicing tape is attached to the entire back surface of the semiconductor wafer to be cut. A Si wafer is used as the semiconductor wafer 1 here.
Next, dicing is performed in the second step shown in FIG. At that time, the back surface chipping occurs when the substrate is put on the back surface of the substrate due to the vibration of the chip during cutting or the like.
Next, in the third step shown in FIG. 4 (3), the distance between the chips is increased by radial stretching. Thereby, the back surface chipping 4 hidden in the shadow of the chip is separated from the chip and appears on the surface of the dicing tape.
Next, ultraviolet irradiation is performed from the upper surface side of the wafer by an ultraviolet irradiation device in a fourth step shown in FIG. The irradiated ultraviolet light exposes the adhesive layer in the region A where no Si chip is present. The irradiated adhesive is cured and its adhesive strength is reduced or eliminated. Thereby, the adhesive force of the back surface chipping 4 in the area A is lowered.
Next, in the fifth step shown in FIG. 4 (5), the back surface chipping 4 can be easily removed by air blowing or running water cleaning 6. Further, even if cleaning is performed under high pressure such as high pressure, the adhesive force in the B region is maintained, so that the Si chip does not scatter.
Subsequently, after cleaning and drying, in the sixth step shown in FIG. 4 (6), ultraviolet light is irradiated from the back surface to reduce the adhesive strength of the entire wafer including the B region. As a result, the chip can be favorably picked up in the seventh step shown in FIG.
Further, in the present embodiment, when the ultraviolet light is irradiated from the surface, the irradiation may be limited to the street.

It is process drawing which shows the outline | summary of the dicing method in Example 1 of this invention. It is a fragmentary sectional view which shows the state of the full dicing in Example 1 of this invention. Process drawing which shows the outline | summary of the dicing method in Example 2 of this invention. Process drawing which shows the outline | summary of the dicing method in Example 3 of this invention. It is the figure which showed the rotary blade front-end | tip part. It is sectional drawing of the semiconductor wafer diced. It is a state figure of the semiconductor wafer fixed to the flame | frame.

Explanation of symbols

1: Semiconductor wafer 2: Adhesive 3: Film-like substrate 4: Back surface chipping 5: Ultraviolet light 6: Air blow / flowing water cleaning 7: Rotating blade 8: Cut groove 9: Crack 10: Frame 11: Dicing tape

Claims (7)

In a semiconductor substrate dicing method of cutting a substrate on which a plurality of semiconductor elements are formed and separating them into individual semiconductor chips,
Adhering the back surface of the substrate to a film base;
Cutting the substrate from the surface with a cutting blade, and cutting into individual semiconductor chips on the film substrate;
Extending the gap between the separated semiconductor chips by stretching the film substrate; and
Cleaning the gap region between the individual semiconductor chips and removing chipping generated on the back surface of the semiconductor substrate;
A method for dicing a semiconductor substrate, comprising:   Between the step of cutting into the individual semiconductor chips and the step of expanding the gap between the individual semiconductor chips, having a step of reducing the adhesive force by curing the adhesive layer of the film substrate. The method for dicing a semiconductor substrate according to claim 1, wherein: In a semiconductor substrate dicing method of cutting a substrate on which a plurality of semiconductor elements are formed and separating them into individual semiconductor chips,
Adhering the back surface of the substrate to the adhesive layer of the film base;
Cutting the substrate from the surface with a cutting blade, and cutting into individual semiconductor chips on the film substrate;
Extending the gap between the separated semiconductor chips by stretching the film substrate; and
Curing the adhesive layer of the film substrate to reduce the adhesive force;
Cleaning the gap region between the individual semiconductor chips and removing chipping generated on the back surface of the semiconductor substrate;
A method for dicing a semiconductor substrate, comprising:   4. The method according to claim 3, wherein, in the step of reducing the adhesive force, an ultraviolet curable adhesive is used for the adhesive layer of the film base material, and the adhesive layer is cured by irradiation with ultraviolet light. Dicing method for semiconductor substrate.   The semiconductor substrate dicing method according to claim 4, wherein the irradiation with the ultraviolet light is performed only on a dicing street.   6. The method of dicing a semiconductor substrate according to claim 5, wherein the irradiation to the dicing street is performed on the interval between the semiconductor chips after the step of expanding the gap between the individual semiconductor chips.   After the step of cleaning the gap region between the individual semiconductor chips and removing the chipping generated on the back surface of the semiconductor substrate, the ultraviolet curable adhesive is cured by irradiating ultraviolet light from the back surface side of the substrate. The method for dicing a semiconductor substrate according to claim 4, further comprising a step of reducing an adhesive force.

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