JPH05144939A - Semiconductor holding device and dicing method - Google Patents

Abstract

PURPOSE:To fix and hold a semiconductor wafer surely by improving groove structure of a vacuum introducing board member and by properly using a vacuum pump regarding a semiconductor holding device and a dicing method. CONSTITUTION:A semiconductor holding device which holds a semiconductor wafer 10 by vacuum. It is provided with a porous board member 16 whereon a semiconductor wafer is mounted and a vacuum introducing board member 18 which has a central groove 20 arranged in opposition to the semiconductor wafer of the porous board member and is positioned in a central part and a plurality of circular grooves 22 provided concentrically around the central groove. A width of at least one circular groove 22 of the circular grooves of the vacuum introducing board member is made equal to a diameter of the central groove 20 or larger.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor holding device and a dicing method. As one of the semiconductor manufacturing processes,
There is a dicing process for cutting a semiconductor wafer into semiconductor chips. In the dicing process, a semiconductor wafer is attached to an annular support frame with an adhesive tape and placed on a dicing table. The dicing table sucks and holds the semiconductor wafer by vacuum.

In dicing, conventionally, a semiconductor wafer is half-cut to cut its thickness halfway,
After that, the method of completely cutting by cracking was adopted. In recent years, according to the demand for high integration and high reliability of ICs, a method has been adopted in which a semiconductor wafer is cut to the middle of an adhesive tape through its entire thickness, and then the cut semiconductor chip is picked up. There is. In the latter case, the semiconductor chip cut at the time of pickup is peeled from the adhesive tape, and the next semiconductor chip is cut, but the position of the adhesive tape on the dicing table when peeling the cut semiconductor chip from the adhesive tape. Tends to shift. If the position of the adhesive tape on the dicing table shifts, it causes a Y-axis shift at the time of cutting the next semiconductor chip, and if such a shift accumulates, defective products may occur. For this reason, it is required that the adhesive tape be held so as not to move on the dicing table.

[0003]

2. Description of the Related Art Conventionally, as shown in FIG. 5, a semiconductor wafer 10 is attached to an annular support frame 14 with an adhesive tape 12. That is, with the adhesive surface of the adhesive tape 12 facing upward, the annular support frame 14 and the semiconductor wafer 10 are placed thereon, and thus the semiconductor wafer 10 is integrated with the support frame 14 and the semiconductor wafer 10
Can be cut together with the adhesive tape 12. The dicing table as a semiconductor holding device used in the dicing process was composed of a porous ceramic porous layer 16 on which the semiconductor wafer 10 is placed, and a vacuum introducing plate member 18 disposed below the porous ceramic porous layer 16.

As shown in FIGS. 5 and 6, the vacuum introducing plate member 18 includes a central groove 20 located in the central portion and a plurality of annular grooves 22 concentrically provided around the central groove 20.
The central groove 20 and the annular groove 22 communicate with each other and are connected to the vacuum pump 24. As the vacuum pump 24, a small and inexpensive convum was used. In the vacuum introducing plate member 18, the central groove 20 and the annular groove 22 are separated by the annular wall 26, and the cross-shaped groove 28 connects the central groove 20 and the annular groove 22 to each other. A vacuum pump 24 was connected to the central groove 20 so that the vacuum spread from the central groove 20 to the annular groove 22 around it. Therefore, the diameter of the central groove 20 is formed larger than the width of the other annular grooves 22.

[0005]

[Problems to be Solved by the Invention] Ceramic Porous 1
Reference numeral 6 has a large number of minute hole structures, and allows the vacuum of the vacuum introducing plate member 18 to pass therethrough to adsorb and hold the adhesive tape 12 of the semiconductor wafer 10. As described above, in order for the adhesive tape 12 to be held so as not to move on the dicing table, it is necessary to receive a sufficiently large vacuum and a uniform vacuum over the entire surface.

[0006] Therefore, the inventor who discovered the tendency of the adhesive tape 12 to move on the dicing table was found by the inventor.
To prevent it from moving on the dicing table,
The attempt was made by increasing the vacuum supplied by the vacuum pump 24. However, the vacuum level supplied by the vacuum pump 24 does not rise as expected, and even if the vacuum is raised as much as possible,
It was not possible to completely eliminate the tendency of the adhesive tape 12 to move on the dicing table.

In particular, when the vacuum supplied by the vacuum pump 24 is increased, the central portion of the ceramic porous 16 is depressed in the vacuum working direction. Then, the adhesive tape 12 that is in contact with the ceramic porous 16 is also dented so that the adhesive tape 12 is not flat, or when the adhesive tape 12 maintains a flat state, the ceramic porous 16
The suction fixing force may be weakened in the recessed part of the. Further, although the vacuum becomes strong in the central portion of the ceramic porous body 16, the vacuum does not become sufficiently high in the peripheral portion of the ceramic porous body 16. Therefore, in the dicing process, the semiconductor wafer 10 is not sufficiently fixed, resulting in a large error in the cutting position, a change in the cut amount of the adhesive tape 12, or a displacement of the adhesive tape 12 during pickup. Has occurred.

Also, in the conventional dicing process, a convum is used as the vacuum pump 24, but there is a limit to the vacuum level that can be achieved with a small-sized convum, and it is insufficient to obtain a large suction fixing force. Was found. Using a large convum may increase the vacuum level, but it is noisy and unsuitable for use in the clean room of a semiconductor manufacturing plant.

It is an object of the present invention to improve the groove structure of the vacuum introducing plate member and to properly use a vacuum pump to securely hold a semiconductor wafer and a semiconductor holding device and a dicing method. Is to provide.

[0010]

A semiconductor holding device according to the present invention is a semiconductor holding device for holding a semiconductor wafer in a vacuum, and a porous plate member on which the semiconductor wafer is placed, and a semiconductor of the porous plate member. The vacuum introduction plate member is provided on the opposite side of the wafer, and includes a vacuum introduction plate member having a central groove located in the central portion and a plurality of annular grooves provided concentrically around the central groove. The width of at least one of the annular grooves is equal to or larger than the diameter of the central groove. Also,
The dicing method of the present invention comprises a porous plate member on which a semiconductor wafer is mounted, a central groove located on the opposite side of the porous plate member from the semiconductor wafer, and a central groove located in the central portion, and around the central groove. A semiconductor holding device including a vacuum introduction plate member having a plurality of concentric circular grooves is prepared, and a vacuum is supplied to the vacuum introduction plate member by a water seal pump to form a semiconductor wafer into the porous plate member. The method is characterized in that the semiconductor wafer is suction-held and held, and the semiconductor wafer is diced with a dicing saw.

[0011]

In the above structure, since the width of at least one of the annular grooves of the vacuum introducing plate member is equal to or larger than the diameter of the central groove,
The vacuum supplied from the central groove spreads evenly to the peripheral annular groove without locally increasing in the central groove, and it is possible to eliminate imperfect fixing due to the depression of the central groove portion of the porous plate member, The fixing at the peripheral portion can be further ensured. In addition, when a water ring pump is used, a high vacuum can be obtained and the noise level is low,
It is particularly suitable for dicing semiconductor devices.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram showing the principle of the present invention and the first embodiment. As in the conventional case, the semiconductor wafer 10 is attached to the annular support frame 14 by the adhesive tape 12. The dicing table as a semiconductor holding device is composed of a table body 30, a porous ceramic porous layer 16 on which the semiconductor wafer 10 is mounted, and a vacuum introducing plate member 18 arranged below the porous ceramic porous layer 16. The ceramic porous 16 is made of a porous material, and the vacuum introducing plate member is made of a metal such as stainless steel. Table body 30
Has a cylindrical concave portion on the upper surface side, and the vacuum introduction plate member 18 and the ceramic porous member 16 are inserted exactly into this cylindrical concave portion. The table body 30 has a through hole 32 and a tube connecting portion 34 in the central portion.

As shown in FIGS. 1 and 2, the vacuum introducing plate member 18 includes a central groove 20 located in the central portion and a plurality of annular grooves 22 provided concentrically around the central groove 20. Have. The central groove 20 and the annular groove 22 are separated by an annular wall 26, and a radial groove 28 connects the central groove 20 and the annular groove 22 to each other. These radial grooves 28 are formed by arranging two sets of cross-shaped grooves with a shift of 45 degrees, and make the communication between the central groove 20 and the annular groove 22 smoother.

The vacuum pump 24 is connected to the tube connecting portion 34 and communicates with the central groove 20. In this example,
As the vacuum pump 24, a water ring pump that can obtain a high vacuum and has low noise is used. For example, a water ring pump can achieve a vacuum from atmospheric pressure to about 750 mmHG. The conventional vacuum used was a vacuum of about 630 or 650 mmHG.

In the embodiment shown in FIGS. 1 and 2, all the annular grooves 22 have the same width and are larger than the diameter of the central groove 20. Accordingly, the annular wall 26
Is smaller than the width of the annular groove 22. For this reason, the vacuum supplied from the central groove 20 is evenly distributed to the peripheral annular groove 22 without locally increasing in the central groove 20, and the ceramic porous 16 is prevented from being dented at the central groove 20 portion. It is possible to maintain a flat posture. The ceramic porous 16 has a large number of minute hole structures, and allows the vacuum of the vacuum introducing plate member 18 to pass therethrough to adsorb and hold the adhesive tape 12 of the semiconductor wafer 10. The ceramic porous 16 undergoes a generally uniform vacuum, and the high vacuum from the vacuum pump 24 further secures the ceramic porous 16 at the periphery. In this way, the adhesive tape 12 receives a sufficiently large vacuum uniformly on the entire surface and is held so as not to move on the dicing table. Therefore, in this state, the semiconductor wafer 10 is diced with a dicing saw. Although not particularly shown, a dicing saw known in the art can be used.

Incidentally, conventionally, the width of the annular groove 22 is set to the central groove 2.
The diameter was smaller than 0. In the present invention, the width of at least one annular groove 22 is equal to or larger than the diameter of the central groove 20, so that the vacuum is concentrated on the central groove 20 of the ceramic porous member 16. It is possible to prevent the occurrence of local depressions.

FIG. 3 shows a second embodiment of the present invention, which has a ceramic porous member 16 and a vacuum introducing plate member 18 as in the first embodiment. In the second embodiment, the width of the annular groove 22 of the vacuum introducing plate member 18 increases toward the outer circumference, and the high vacuum from the vacuum pump 24 further secures the fixing of the ceramic porous member 16 at the peripheral portion. It is like this. Therefore, the tendency of the central portion of the ceramic porous 16 to be depressed is alleviated more and more. When the vacuum is locally concentrated on the central portion of the ceramic porous 16 as in the conventional case, the lateral force is weak, whereas if the fixing at the peripheral portion of the ceramic porous 16 is strengthened, the adhesive tape 12 moves. Can be effectively prevented. Further, in this embodiment, the width of the annular groove 22 is all larger than the diameter of the central groove 20.

FIG. 4 shows a third embodiment of the present invention, which has a ceramic porous member 16 and a vacuum introducing plate member 18 as in the first embodiment. The annular grooves 22 are all formed to have the same width and larger than the diameter of the central groove 20. In the third embodiment, the vacuum pump 24 is line 3
6 individually connected to the central groove 20 and the annular groove 22,
A pressure regulator 38 is arranged on each line 36. Therefore, according to this configuration, the adhesive tape 12
The vacuum levels of the central groove 20 and the annular groove 22 can be individually and optimally controlled so that the movement of the grooves can be effectively prevented.

The pressure regulator 38 of the third embodiment can also be adopted in the case of the structure of the second embodiment, for example, when the width relationship between the central groove 20 and the annular groove 22 changes. Further, in the above description, the ceramic porous 1
Although 6 and the vacuum introducing plate member 18 are configured as separate members, such a member may be integrated. For example, ceramic porous 1 as the porous plate member
When a metal porous material is used instead of 6, the vacuum introducing plate member 18 can be provided integrally with the metal porous material.

[0020]

As described above, according to the present invention,
Since the width of at least one of the annular grooves of the vacuum introducing plate member is equal to the diameter of the central groove or larger than the width of the central groove, the vacuum supplied from the central groove is at the center. The groove is spread evenly to the peripheral annular groove without locally increasing in size, and it is possible to eliminate the improper fixing due to the depression of the central groove portion of the porous plate member,
The fixing at the peripheral portion can be further ensured.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle of the present invention and also a first embodiment.

FIG. 2 is a plan view of the vacuum introduction plate member of FIG.

FIG. 3 is a diagram showing a second embodiment of the present invention.

FIG. 4 is a diagram showing a third embodiment of the present invention.

FIG. 5 is a diagram showing a conventional technique.

FIG. 6 is a plan view of the vacuum introducing plate member of FIG.

[Explanation of symbols]

 10 ... Semiconductor wafer 12 ... Adhesive tape 16 ... Ceramic porous 18 ... Vacuum introducing plate member 20 ... Central groove 22 ... Annular groove 24 ... Vacuum pump 26 ... Annular wall 38 ... Pressure regulator

Claims (9)

[Claims] 1. A semiconductor holding device for holding a semiconductor wafer (10) in a vacuum, wherein a porous plate member (16) on which the semiconductor wafer is placed and a side of the porous plate member opposite to the semiconductor wafer. A vacuum introduction plate member (18) having a central groove (20) arranged in the central portion and a plurality of annular grooves (22) provided concentrically around the central groove.
And the width of at least one annular groove (22) of the annular grooves of the vacuum introduction plate member is equal to or greater than the diameter of the central groove (20). Holding device. 2. The semiconductor holding device according to claim 1, wherein all of the widths of the annular groove (22) are equal to or larger than the diameter of the central groove (20). 3. The semiconductor holding device according to claim 1, wherein the width of the annular groove (22) increases toward the outer periphery. 4. The central groove (20) and the annular groove (22).
2. The semiconductor holding device according to claim 1, further comprising means (38) for adjusting the pressure of each. 5. The semiconductor holding device according to claim 1, wherein the porous plate member is made of ceramic porous material, and the vacuum introduction plate member is made of metal. 6. The semiconductor holding device according to claim 1, wherein the porous plate member and the vacuum introducing plate member are made of metal porous. 7. A porous plate member (16) on which a semiconductor wafer is placed, a central groove (20) arranged on the opposite side of the porous plate member from the semiconductor wafer, and located in the center, and the center. A plurality of annular grooves (2 provided concentrically around the groove)
2) and a vacuum holding plate member (18) having a semiconductor holding device is prepared, and a vacuum is supplied to the vacuum introducing plate member (18) by a water-sealed pump (24) so that the semiconductor wafer (10) is held. A dicing method, characterized in that the semiconductor wafer (10) is held by suction on a porous plate member (16) and is diced with a dicing saw. 8. The dicing method according to claim 7, wherein the semiconductor wafer (10) is attached to an adhesive tape (12), and the adhesive tape is placed on the porous plate member (16). 9. When preparing the semiconductor holding device,
The width of at least one annular groove (22) of the annular grooves of the vacuum introduction plate member is equal to or larger than the diameter of the central groove (20). Item 7. The dicing method according to Item 7.