JPH06151585A - Dicing device - Google Patents

Abstract

PURPOSE:To prevent a dicing device from causing the clogging of a suction groove by dust, chips, etc., by providing an opening for suction at the topside of a dicing table, and sucking and holding a pallet on the topside, and sticking a wafer onto the pallet through a double-sided adhesive tape. CONSTITUTION:A pallet 10, whereon a wafer 30 is stuck through a double-sided adhesive sheet 20, is placed on a dicing table 1, and the pallet 10 is heated after cutting the wafer 30, using a diamond blade 40. Though the adhesive strength of the first binder layer 22 of the adhesive sheet 20 drops by heating, the adhesive strength of the second binder layer 23 does not drop. Since the adhesive sheet 20 sticks fast fast to the pallet 10 by the binder layer 23, a chip can be taken out easily of the adhesive sheet 20. The dust, chips, etc., adhering to the pallet 10 fall onto the dicing table 1, and one part of them may get in a suction groove 2, but the suction groove 2 has an opening area, so it cannot cause clogging.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dicing apparatus for separating a wafer made of, for example, ceramics or silicon into chips by using a diamond blade or the like.
Particularly, it relates to a structure for holding a wafer on the dicing table.

[0002]

2. Description of the Related Art Conventionally, a dicing apparatus for separating a large number of silicon chips from a silicon wafer has been known. This dicing device attaches a wafer onto the adhesive surface of an adhesive sheet that has an adhesive layer whose adhesive strength is reduced by irradiating ultraviolet rays on one side, and places the non-adhesive surface of the adhesive sheet on a dicing table. To do. The dicing table is made of a porous material, and the adhesive sheet is evenly adsorbed by vacuum suction from the lower surface side thereof. In this state, the wafer is subdivided by dicing with a diamond blade or the like. After that, the vacuum suction is stopped and the pressure-sensitive adhesive sheet is transferred to the expanding device together with the finely divided wafer, and the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer on the pressure-sensitive adhesive sheet is reduced by irradiating with ultraviolet rays, and the sheet is stretched individually. After increasing the distance between the silicon chips, the silicon chips are taken out from the adhesive sheet by the suction chuck device and the push-up pin.

[0003]

However, in the case of the above dicing apparatus, since the dicing table is made of a porous material, the unit price of the product is high, and moreover, the clogging is likely to occur due to dust or shavings. for that reason,
When the number of times of use increases, the sheet cannot be stably adsorbed, and there is a problem that the sheet and the wafer are displaced during the dicing. Therefore, an object of the present invention is to provide a dicing device which has a low unit price of the dicing table, is unlikely to be clogged with dust or shavings, and can be stably used many times. Another object is to provide a dicing device in which chips can be easily taken out after dicing.

[0004]

In order to achieve the above object, the dicing apparatus of the present invention is provided with a suction opening connected to a vacuum suction device on the upper surface of a dicing table,
A pallet made of a hard plate is adsorbed and held on this upper surface, and a wafer is attached onto the pallet via a double-sided adhesive sheet. The pressure-sensitive adhesive layer on the wafer side of the pressure-sensitive adhesive sheet is a first pressure-sensitive adhesive layer whose adhesive strength is reduced by heating or ultraviolet irradiation, and the pressure-sensitive adhesive layer on the pallet side of the pressure-sensitive adhesive sheet is not decreased in adhesive strength by heating or ultraviolet irradiation. Alternatively, it is the second pressure-sensitive adhesive layer in which the decrease in the pressure-sensitive adhesive force due to heating or ultraviolet irradiation is less than that of the pressure-sensitive adhesive layer on the wafer side.

[0005]

First, the lower surface (second adhesive layer) side of the double-sided adhesive sheet is attached to the upper surface of the pallet, and the wafer is attached to the upper surface (first adhesive layer) side of the double-sided adhesive sheet. As a result, the sheet and the wafer are held integrally with the pallet. Place this pallet on the dicing table,
The pallet is suction-held by vacuum suction from the suction opening of the dicing table. Dicing is performed in this state. Unlike the conventional porous hole, the suction opening has a certain opening area, but since the pallet itself has rigidity, it does not bend, and the suction opening of the dicing table is not clogged. Stable holding power can be maintained without causing it. After dicing, suction and hold are stopped, the pallet is removed from the dicing table, and the pallet is heated or irradiated with ultraviolet rays. As a result, the adhesive force of the first adhesive layer is reduced, and when the individual chips are taken out from the sheet by a suction chuck device or the like in this state, the sheet has the second adhesive layer in close contact with the pallet. Can be taken out easily.

The suction opening of the dicing table may be, for example, a plurality of holes or a continuous groove. The suction opening has an opening area such that the pallet does not bend when the pallet is adsorbed. In other words, when the suction opening has a predetermined opening area, the rigidity is such that the pallet itself does not bend. It is necessary to have Also,
It is desirable to disperse the suction openings on the upper surface of the dicing table so that almost the entire area of the pallet can be sucked uniformly. As the first pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, a foaming peelable pressure-sensitive adhesive whose adhesive strength is reduced by heating or an adhesive whose adhesive strength is reduced by ultraviolet irradiation can be used.
When the first pressure-sensitive adhesive layer is a foam-peeling pressure-sensitive adhesive, the heating temperature is about 120 ° C.
It is desirable to use a relatively heat resistant material such as aluminum or glass. In the case where the first adhesive layer is an adhesive whose adhesive strength is reduced by ultraviolet irradiation, the palette transmits ultraviolet rays like quartz glass so that the first adhesive layer can be irradiated with ultraviolet rays from the lower side. It is desirable to use materials.

[0007]

1 and 2 show an example of a dicing apparatus according to the present invention. The dicing table 1 is made of a non-porous material, and a plurality of pedestals 3 partitioned by suction grooves 2 having a constant depth are formed on the upper surface. The upper surface of this pedestal 3 is located on the same plane as the upper surface of the peripheral portion 4. A total of three positioning pins 5 are provided on the upper surface of the peripheral portion 4 in a protruding manner. A plurality of ventilation holes 6 are formed on the bottom surface of the suction groove 2, and these ventilation holes 6 are connected to a vacuum suction device 8 via a tube 7 connected to the lower surface of the dicing table 1.

On the upper surface of the dicing table 1, a rectangular plate-shaped pallet 10 slightly larger than the contour of the suction groove 2 is adsorbed. The pallet 10 is positioned at a fixed position by pressing two adjacent sides of the pallet 10 against the positioning pins 5 by an air cylinder device or the like (not shown). The pallet 10 is a hard plate made of iron, aluminum, glass or the like, and its upper and lower surfaces are flat and smooth surfaces.

A wafer 30 is attached to the upper surface of the pallet 10 via a double-sided adhesive sheet 20. As shown in FIG. 3, the double-sided pressure-sensitive adhesive sheet 20 has a first pressure-sensitive adhesive layer 22 formed on one surface of a base film 21 made of a synthetic resin film such as a PET film, and a second pressure-sensitive adhesive layer 23 on the other surface.
Is formed. The first pressure-sensitive adhesive layer 22 is made of a foam-peeling pressure-sensitive adhesive whose adhesive strength is reduced by heating, and for example, an acrylic pressure-sensitive adhesive or an isobutane-based pressure-sensitive adhesive can be used. The second pressure-sensitive adhesive layer 23 is a pressure-sensitive adhesive such as an acrylic pressure-sensitive adhesive whose adhesive strength does not decrease by heating, or the first adhesive layer 2 whose adhesive strength decreases by heating.
Less than 2 adhesives such as acrylic adhesives are used. The second adhesive layer 23 of the adhesive sheet 20 is attached to the upper surface of the pallet 10, and the wafer 30 is attached to the upper surface of the first adhesive layer 22.

The operation of the dicing device will be described below. First, the pallet 10 having the wafer 30 attached to the upper surface of the dicing table 1 via the double-sided adhesive sheet 20 is attached.
It is placed on top and pressed against the positioning pin 5 for positioning. In this state, the vacuum suction device is driven to move the pallet 10
Is suction-held on the upper surface of the dicing table 1. At this time, since the suction groove 2 on the upper surface of the dicing table 1 evenly adsorbs almost the entire area of the pallet 10 and the pallet 10 itself has strength, the pallet 10 is not bent or warped. Diamond blade 4 in this state
The wafer 30 is cut by using 0. At the time of dicing, the blade 40 forms a cut reaching the adhesive sheet 20, but is adjusted so as not to damage the pallet 10.
After dicing, the pallet 10 is taken out from the dicing table 1 and conveyed to a heating device (not shown) to heat the pallet 10. The heating reduces the adhesive force of the first adhesive layer 22 of the adhesive sheet 20, but does not reduce the adhesive force of the second adhesive layer 23. In this state, if the individual chips 31 are sucked by a suction chuck device or the like, the adhesive sheet 20
Is adhered to the pallet 10 by the second adhesive layer 23, the chip 31 can be easily taken out from the adhesive sheet 20, and no excessive force is applied to the chip 31. When removing the pallet 10 from the dicing table 1, dust or shavings attached to the pallet 10 may drop onto the dicing table 1 and part of the dust may enter the suction groove 2, but the suction groove 2 is opened to some extent. Since it has an area, it does not cause clogging.

The present invention is not limited to the above embodiment. The present invention can be used for dicing other wafers in addition to silicon wafers and ceramic wafers. Further, the dicing table may be provided with a plurality of suction holes instead of the suction grooves.

[0012]

As is apparent from the above description, according to the present invention, the suction opening is provided on the upper surface of the dicing table, and the pallet made of the hard plate is sucked and held on the upper surface. Unlike the porous dicing table, the dicing table can be manufactured at low cost, is unlikely to be clogged with dust or shavings, and can be used stably many times. Further, since the wafer is attached to the pallet by the double-sided adhesive sheet, the sheet does not bend when the wafer is transferred to the heating device or the ultraviolet irradiation device after dicing, and the chips can be safely transferred without dropping. Further, since the adhesive force of the wafer-side adhesive layer of the adhesive sheet is lowered by heating or irradiation with ultraviolet rays, the sheet does not float up when the chip is taken out and can be taken out easily.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of a dicing apparatus according to the present invention.

FIG. 2 is a sectional view of the dicing device of FIG.

FIG. 3 is a cross-sectional view of a double-sided PSA sheet.

[Explanation of symbols]

 1 Dicing Table 2 Suction Groove (Suction Opening) 8 Vacuum Suction Device 10 Pallet 20 Double-sided Adhesive Sheet 22 First Adhesive Layer 23 Second Adhesive Layer 30 Wafer 40 Blade

Claims (1)

[Claims] 1. A dicing apparatus for holding a wafer on a dicing table and cutting the wafer by a rotating blade to separate the chips into chips. A suction opening connected to a vacuum suction device on the upper surface of the dicing table. Is provided, and a pallet made of a hard plate is adsorbed and held on this upper surface, and a wafer is attached on the pallet via a double-sided adhesive sheet, and the adhesive layer on the wafer side of the adhesive sheet is adhered by heating or ultraviolet irradiation. The pressure-sensitive adhesive layer is the first pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer on the pallet side of the pressure-sensitive adhesive sheet does not lose its adhesive force by heating or UV irradiation, or the adhesive force by heating or UV irradiation is higher than that on the wafer side. Second with less decrease in
A dicing device, which is an adhesive layer.