JP4686010B2 - Polishing pad - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polishing pad used for polishing a member to be polished such as a semiconductor or an electronic component. More specifically, the polishing pad of a member to be polished such as a semiconductor wafer is improved in flatness and has a long life. The present invention relates to a polishing pad that can be made simple.
[0002]
[Prior art]
In general, when polishing a wafer, the polishing pad is held on the lower surface plate side, the wafer as the object to be polished is held on the upper surface plate side, and the wafer and the polishing pad are pressurized while supplying the polishing slurry. This is done by sliding it.
[0003]
Incidentally, as shown in FIG. 5 , the conventional polishing pad has a pad main body 10, a base layer 11 laminated on the pad main body 10 with a pressure-sensitive adhesive layer 15, and a double-sided adhesive tape 14. ing. When manufacturing such a polishing pad 20, as shown in FIG. 6 , the base layer 11 and the pad main body 10 are bonded to each other with a double-sided adhesive tape 15, and polishing is performed by punching this laminate into a polishing pad shape. The pad 20 is obtained.
[0004]
However, when the wafer is polished using the polishing pad 20, the slurry penetrates into the inside from the peripheral side surface of the foundation layer 11, and as a result, the physical properties such as the compressibility of the foundation layer change due to the penetration of the slurry. Thus, there is a drawback that the polishing performance is lowered, and a defect such as peeling between the adhesive layer and the underlying layer occurs due to the penetration of the slurry.
[0005]
Furthermore, in a polishing pad provided with a transparent window member through which laser light or visible light passes in order to measure the polishing rate of the wafer surface while polishing the wafer, the slurry soaks into the measurement window. For this reason, there is a disadvantage that detection failure occurs.
[0006]
[Problems to be solved by the invention]
The present invention has been made in order to eliminate the above-mentioned drawbacks. The object of the present invention is to prevent the slurry from penetrating into the underlayer, so that the polishing characteristics are not adversely affected, and the polishing rate is not affected. It is an object of the present invention to provide a polishing pad that can improve the detection accuracy of.
[0011]
[Means for Solving the Problems]
The polishing pad according to claim 1 is a polishing pad having an underlayer and a pad main body laminated on the surface of the underlayer, and on the surface of the underlayer on the surface side of the underlayer at the periphery of the underlayer. The groove is formed along the periphery of the underlayer, thereby achieving the above object.
[0012]
In one embodiment, the groove is formed by the notch portions of the underlying layer.
[0013]
In one embodiment, a seal member is disposed in the groove.
[0014]
The operation of the present invention is as follows.
[0015]
In order to to grant excellent polishing properties to the polishing pad, the base layer is made of those generally porous having elasticity, thus, the slurry from the peripheral surface of the undercoat layer is to easily penetrate into the interior but, in the present invention, the peripheral portion of the base layer, by grooves in the surface of the surface plate side of the underlayer is formed along the periphery of the base layer, that slurry penetrates into the interior underlayer Therefore, it is possible to moderate the change in the polishing characteristics (uniformity), thereby improving the yield, improving the productivity and stabilizing the quality.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below.
Migaku Ken pad 1 includes a porous base layer 11 and the pressure-sensitive adhesive layer on the surface of the underlying layer 11 pad body 10 laminated via a (double-sided adhesive tape) 15 having elasticity.
[0017]
The pad body 10 is usually formed of a resin layer having fine bubbles. The underlayer 11 is formed of a synthetic resin foam layer or a nonwoven fabric having elasticity compared to the pad main body 10. A release sheet (not shown) is laminated on the back surface of the base layer 11 via a pressure-sensitive adhesive layer (double-sided adhesive tape) 14, and the release sheet is peeled off to place the pressure-sensitive adhesive layer 14 on a surface plate. The polishing pad 1 is used by sticking to the surface.
[0018]
The pad body 10 can be manufactured from one or more of urethane resin, acrylic resin, polycarbonate, polyamide, polyester and the like by a known casting method, extrusion molding method, or the like. Usually, it is manufactured by a casting method or an extrusion molding method using a thermoplastic resin, but may be manufactured by heat curing using a thermosetting resin.
[0019]
The underlayer 11 can be produced from one or more of urethane resin, acrylic resin, polycarbonate, polyamide, polyester and the like by a known casting method, extrusion molding method, or the like. Usually, a thermoplastic resin is used and manufactured by a casting method or an extrusion molding method. Moreover, it can also form with the material which has air permeability like a nonwoven fabric.
[0029]
(Working-shaped state)
In the embodiment shown in FIG. 1 , a groove 13 is formed on the lower surface of the peripheral portion of the base layer 11 as the waterproof layer 12 formed on the peripheral portion of the base layer 11.
[0030]
The groove 13 is formed along the periphery of the base layer 11 on the surface of the base layer 11 on the surface plate side, and has a ring shape when viewed from the lower surface side of the base layer 11. The width of the groove wafer b is preferably 1 to 4 mm, and the dimension from the peripheral end surface of the base layer 11 is preferably 1 to 4 mm. Especially preferably, it is about 2-3 mm respectively. A plurality of grooves 13 may be formed concentrically.
[0031]
In order to form the groove 13 on the lower surface of the underlayer 11, a known method can be employed. For example, a cut may be made on the back surface side of the underlayer 11 with a cutting blade to separate it.
[0032]
As shown in FIG. 2 , the polishing pad 1 manufactured in this manner is attached to the lower surface plate 2, and the slurry supplied between the polishing pad 1 and the wafer is introduced into the underlayer 11 from its peripheral side surface. When trying to permeate, it is blocked at the groove 13 and flows downward, so that the slurry does not penetrate into the base layer 11 on the lower surface plate 2.
[0033]
As shown in FIG. 3 , when the polishing pad 1 is stuck on the lower surface plate 2, a seal member 17 is preferably disposed in the groove portion 13. As the seal member 17, for example, an O-ring, a sealing agent, or the like can be used. In this case, the slurry that permeates from the peripheral end surface of the base layer 11 is blocked by the seal member 17 and does not enter the base layer 11 any more.
[0034]
The polishing pad 1 may have a transparent window member formed on a part thereof. In this case, an opening is formed in the base layer 11 at a position corresponding to the window member.
[0041]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples.
( Example)
As shown in FIG. 4 , the pad main body is laminated on the underlayer via the second double-sided adhesive tape, and a groove is formed on the lower surface side of the outer peripheral portion of the underlayer. The underlayer is bonded to the first double-sided adhesive. The polishing machine was operated with the tape attached to the lower surface plate 2 with nothing attached to the carrier, and the permeability of the slurry was visually observed.
[0042]
The test conditions are as follows.
Polishing machine: Strasbaugh's Down force: 4.3 (psi)
Platen speed: 30 (rpm)
Carrier speed: 27 (rpm)
Carrier diameter: 230 (mm)
Liquid used: Slurry Slurry flow rate: 300 (ml / min) Circulation system operation time: 480 (min)
As a result of the test, no permeation of the slurry from the end of the underlayer was observed. Furthermore, no peeling was observed between the underlayer and the pad body.
[0043]
When the conventional polishing pad was tested under the same conditions as in the example, the penetration of the slurry (about 20 mm) from the end of the underlayer was observed.
[0044]
【The invention's effect】
According to the present invention, since the slurry can be prevented from penetrating into the underlayer, the polishing characteristics are not adversely affected, and the detection accuracy of the polishing rate can be increased. Therefore, changes in polishing characteristics (uniformity) can be moderated, thereby improving yield, improving productivity, and stabilizing quality.
[Brief description of the drawings]
[1] Figure 1 (a) is a fragmentary cross-sectional view of the implementation form of the polishing pad of the present invention. FIG. 1B is a plan view of the polishing pad.
FIG. 2 is an explanatory diagram of use of the polishing pad shown in FIG.
FIG. 3 is a schematic cross-sectional view of another embodiment of the polishing pad of the present invention .
FIG. 4 is an explanatory diagram of an embodiment .
FIG. 5 is a cross-sectional view of a conventional polishing pad .
FIG. 6 is a schematic view showing a conventional method for producing a polishing pad .
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Polishing pad 2 Polishing machine 10 Pad main body 11 Base layer 12 Waterproofing layer 13 Groove part 14 1st double-sided adhesive tape 15 2nd double-sided adhesive tape

Claims (3)

A polishing pad having an underlayer and a pad body laminated on the surface of the underlayer, wherein a groove is formed along a periphery of the underlayer in a peripheral surface of the underlayer at a side surface of the base layer. Polishing pad . The polishing pad according to claim 1, wherein the groove is formed by cutting out a part of the base layer . The polishing pad according to claim 1, wherein a seal member is disposed in the groove .

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