KR101889081B1 - Polishing pad and preparation method thereof - Google Patents

Abstract

According to an embodiment of the present invention, provided is a method for manufacturing a polishing pad, which comprises: a polishing layer having a first through-hole; a support layer having a second through-hole; an adhesive layer having a third through-hole and disposed between the polishing layer and the support layer; and a window inserted into the first through-hole and having a notch-processed area at a lower edge portion adhered to the adhesive layer. Accordingly, delamination between layers can be prevented.

Description

TECHNICAL FIELD [0001] The present invention relates to a polishing pad,

Embodiments relate to a polishing pad for use in a chemical mechanical planarization (CMP) process of semiconductors and a method of manufacturing the same.

A chemical mechanical planarization (CMP) process during a semiconductor manufacturing process is a process in which a wafer attached to a head is brought into contact with the surface of a polishing pad formed on a platen, And the platen and the head are relatively moved while reacting, thereby mechanically flattening the uneven portion of the wafer surface.

It is also important to determine the end point at which the process is terminated by detecting the point at which the desired surface properties or thickness are obtained in the CMP process. Thus, various planarization endpoint determination methods have been developed and, as an example, there is an optical technique for providing a transparent window to the polishing pad to select the wavelength of light. The light beam is directed to the surface of the wafer being processed through the window, which is reflected back to the detector through the window. The wafer surface characteristics can be measured based on the return signal.

A conventional laminated polishing pad having a window is generally bonded after forming holes penetrating the polishing layer and the support layer, respectively. At this time, to align the holes of the abrasive layer with the holes of the support layer, notches were formed on the abrasive layer and the support layer to align them, but this alignment process was inconvenient.

In addition, although a method of removing a lower end portion of a desired position by forming a peelable protective member at a portion corresponding to the light transmitting region has been developed, there is a problem that the optical transparency is lowered because the adhesive layer remains at the lower end of the light transmitting region Patent Publication No. 10-1633766).

Korean Patent Registration No. 10-1633766 (Rohm and Haas Electronic Materials CMP Holdings, Inc.) 2016.06.21.

Since the conventional laminated polishing pad having a window generally has a hole formed in the polishing layer and the supporting layer and then adhered to each other, the process of forming the light transmitting region at a predetermined position at the time of manufacturing is troublesome, There is a problem that the optical transmittance is lowered as the layer is present.

Therefore, the object of the embodiment is to provide a polishing pad capable of easily forming a light transmitting region at a predetermined position without forming a notch and preventing interlayer separation by enhancing the interlaminar adhesive force without lowering the optical transmittance, and a manufacturing method thereof .

In order to achieve the above object,

(a) providing an abrasive layer;

(b) forming a first through hole through the polishing layer;

(c) providing a support layer opposite the polishing layer;

(d) adhering the abrasive layer and the support layer to each other through the adhesive layer, wherein an adhesive layer is interposed between the abrasive layer and the support layer in which the first through hole is formed;

(e) forming a third through hole passing through the adhesive layer in a predetermined region of the adhesive layer with respect to the first through hole, and a second through hole passing through the support layer in a predetermined region of the support layer; And

(f) inserting a window having a notched region in the lower edge portion into the first through hole.

According to another aspect of the present invention,

An abrasive layer having a first through hole formed therein;

A second penetrating hole formed in the region where the first through hole is formed, and a supporting layer opposed to the polishing layer;

An adhesive layer interposed between the polishing layer and the supporting layer, the third through-hole being formed in the region where the first through hole is formed; And

And a window inserted into the first through hole and having a notched region at a bottom edge portion adhered to the adhesive layer,

The first through hole and the second through hole are aligned with each other without forming a notch for aligning the first through hole and the second through hole in the polishing layer and the supporting layer .

The polishing pad manufacturing method according to the embodiment can easily form the light transmitting region at a predetermined position without forming a notch.

In addition, according to the polishing pad manufacturing method according to the embodiment, since there is no adhesive layer at the bottom of the window, a polishing pad having excellent optical transparency can be formed.

Further, according to the polishing pad manufacturing method according to the embodiment, the hot-melt adhesive is used instead of the double-sided tape when bonding the abrasive layer and the support layer, and the window is fixed by allowing the hot-melt adhesive to permeate into the notched area of the lower- The interlaminar adhesive strength is strengthened and interlayer delamination is prevented.

1 schematically shows a method of manufacturing a polishing pad according to an embodiment.
2 schematically illustrates a cutting method according to one embodiment.
Fig. 3 schematically shows a cutting method according to another embodiment.
4 shows a polishing pad manufactured by a method of manufacturing a polishing pad according to an embodiment.
Figure 5 shows a window with a notched region at the bottom edge.

Hereinafter, a method of manufacturing a polishing pad according to an embodiment will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals refer to the same components, and the sizes and thicknesses of the respective components may be exaggerated for convenience of explanation. On the other hand, the embodiments described below are exemplary and various modifications are possible from these embodiments.

A method of manufacturing a polishing pad according to an embodiment will be described with reference to FIG.

The polishing pad manufactured by the method of manufacturing the polishing pad has a polishing layer 101, a first through hole 201 penetrating the polishing layer, a supporting layer 102, a polishing layer 101 and the supporting layer 102, And a window 104B which is inserted into the first through hole 201 and has a notched portion at a bottom edge portion adhered to the adhesive layer 103. [

First, the polishing layer 101 is provided (see " (a) " in FIG. 1).

The abrasive layer 101 may be a foam or a non-foam, and preferably a foam having micro-bubbles.

The abrasive layer 101 may be formed of a polyurethane resin, a polyester resin, a polyamide resin, an acrylic resin, a polycarbonate resin, a halogen resin, a polystyrene resin, a polyolefin resin, an epoxy resin, But is not limited to, any combination thereof.

The polyurethane resin is excellent in abrasion resistance and can be obtained as a material for forming the polishing layer 101 because a polymer having desired physical properties can be easily obtained by variously changing the raw material composition.

The surface of the polishing layer 101 preferably has a concavo-convex structure for maintaining and updating the slurry. In addition, although the concavo-convex structure is generally regular, it is possible to change the groove pitch, groove width, groove depth and the like at specific positions in order to maintain and update the slurry.

The shape of the abrasive layer 101 is not particularly limited, and the size of the abrasive layer 101 can be appropriately adjusted according to the polishing apparatus used.

The thickness of the abrasive layer 101 is not particularly limited, but may be 0.8 to 5.0 mm, preferably 1.0 to 3.0 mm.

Then, a first through hole 201 penetrating the polishing layer 101 is formed (see "(b)" in FIG. 1).

The method of forming the first through hole 201 through the polishing layer 101 includes a method of pressing or grinding with a cutting tool, a method using a laser such as a carbonic acid laser, a method of forming a first through hole 201 A method in which a raw material is introduced into a mold to be cured, and the like, but the present invention is not limited thereto.

The plane shape of the first through hole 201 is not particularly limited and may be circular, elliptical, square, rectangular, or polygonal.

Next, a support layer 102 opposed to the abrasive layer 101 is provided (see "(c)" in FIG. 1).

The support layer 102 may be a polyester nonwoven fabric impregnated with a polyurethane resin, a polyurethane resin suede type, a polyurethane foam type foam, or any combination thereof, but is not limited thereto.

The thickness of the support layer 102 is not particularly limited, but may be 0.1 to 3.0 mm, preferably 0.4 to 1.5 mm.

An adhesive layer 103 is interposed between the polishing layer 101 and the supporting layer 102 where the first through hole 201 is formed and the polishing layer 101 and the supporting layer 102 are bonded to each other through the adhesive layer 103. [ (See Fig. 1 (d)).

The adhesive layer 103 may include, but is not limited to, a polyurethane resin, a polyester resin, an ethylene-vinyl acetate resin, a polyamide resin, a polyolefin resin, or any combination thereof. Preferably, the adhesive layer 103 may be a polyurethane resin, a polyester resin, or any combination thereof.

The adhesive layer 103 may include a first adhesive layer attached to one side of the polishing layer 101 and a second adhesive layer attached to one side of the supporting layer 102.

The adhesive layer 103 may include a first adhesive layer attached to one side of the polishing layer 101 and a second adhesive layer attached to one side of the supporting layer 102.

For a description of the materials of the first adhesive layer and the second adhesive layer, refer to the description of the material of the " adhesive layer 103 ".

The thickness of the adhesive layer 103 may be 10 to 400 mu m, and preferably 20 to 250 mu m.

The thickness of the first adhesive layer may be 5 to 200 mu m, preferably 10 to 125 mu m.

The thickness of the second adhesive layer may be 5 to 200 탆, and preferably 10 to 125 탆.

When the thickness of the adhesive layer 103 is in the above range, the polishing layer and the support layer can be attached by melting at a low temperature, and the adhesive strength is strong.

The adhesive layer 103 may be formed by heating the first adhesive layer and the second adhesive layer to melt some or all of the first adhesive layer and the second adhesive layer, and then adhering the first adhesive layer and the second adhesive layer in contact with each other.

The melting temperature of the first adhesive layer and the second adhesive layer may be 80 to 170 ° C.

When the melting temperature of the first adhesive layer and the second adhesive layer is in the above range, the adhesion of the adhesive layer 103 is excellent and the peeling between the polishing layer 101 and the support layer 102 can be prevented easily, It is possible to prevent the layer 101 or the support layer 102 from being deformed or deteriorated.

When the polishing layer 101 and the supporting layer 102 are bonded using the adhesive layer 103, the polishing layer 101 and the supporting layer 102 are not easily peeled off even when a long time of polishing proceeds, The slurry permeation preventing performance can be excellent.

A third through hole 203 penetrating the adhesive layer 103 is formed in a predetermined region of the adhesive layer 103 with respect to the first through hole 201 and a predetermined region of the support layer 102, A second through hole 202 penetrating the support layer 102 is formed (see "(e)" in FIG. 1).

The third through-hole 203 is formed in the region where the first through-hole 201 is formed, and the planar area of the third through-hole 203 is smaller than the planar area of the first through-hole 201.

The second through-hole 202 is formed in a region where the first through-hole 201 is formed, and the planar area of the second through-hole 202 is smaller than the planar area of the first through-hole 201 .

The plane shape of the third through hole 203 is not particularly limited and may be circular, elliptical, square, rectangular or polygonal.

The plane shape of the second through hole 202 is not particularly limited, and may be circular, elliptical, square, rectangular, or polygonal.

When the planar area of the third through-hole 203 and the planar area of the second through-hole 202 are made smaller than the planar area of the first through-hole 201, the window can be supported at the lower end of the first through- Since the adhesive layer 103 and the supporting layer 102 are present, the window can be effectively fixed to the first through hole 201.

The third through hole 203 and the second through hole 202 are simultaneously formed so that the third through hole 203 and the second through hole 202 correspond to each other.

The method of forming the third through hole 203 and the second through hole 202 may be a method of cutting using a guide member.

The step of forming the third through hole 203 and the second through hole 202 with reference to the first through hole 201 may include forming a through hole 201 in the first through hole 201, Inserting a member; Aligning the cut portion with a predetermined position by the guide member; And cutting the adhesive layer and a part of the supporting layer by the cutting portion.

The cutting portion may be fixed to the guide member or guided by the guide member.

The guide member may contact the inner surface of the first through hole 201 to guide the cut portion.

The cutting portion can cut the adhesive layer 103 and the support layer 102 at the same time.

The method of forming the third through hole 203 and the second through hole 202 is different from the method of forming a through hole in the polishing layer and the supporting layer respectively and then adhering to each other, Since the region can be formed at a predetermined position, the manufacturing process is simple. If the third through hole 203 and the second through hole 202 are formed so as to correspond to the first through hole 201, the adhesive layer 103 does not exist in the light transmitting region Therefore, a polishing pad having excellent optical detection accuracy can be produced.

Then, a window 104B having a notched portion at the lower edge portion is inserted into the first through hole 201 (refer to "(f)" in FIG. 1).

The window 104B having the notched portion at the lower edge portion is manufactured by notching the lower edge portion of the un-notched window 104A.

Specifically, the lower end edge portion of the window is notched by rotating the diamond tip while moving the window fixing jig that is not notched, or the router device which moves while rotating the diamond tip while fixing the window not- And the bottom edge of the window is notched.

The non-notched window 104A may be the same size as the first through hole 201.

The windows 104A and 104B may be foamed or non-foamed, and preferably may be non-foamed. If the windows 104A and 104B are non-foamed, the micro-bubbles do not exist in the windows 104A and 104B, so that the possibility of infiltration of slurry is reduced, thereby improving the optical detection precision and preventing damage to the light- have.

The windows 104A and 104B may be formed of any one of a polyester resin, a polyamide resin, an acrylic resin, a polycarbonate resin, a halogen resin, a polystyrene resin, a polyolefin resin, an epoxy resin, a photosensitive resin, But is not limited thereto.

However, it is preferable that the windows 104A and 104B have a wear rate equal to or slightly higher than that of the material used for the polishing layer 101. [ If the abrasion rate of the window 104 is smaller than the abrasion rate of the abrasive layer 101, scratches may be generated on the wafer to be polished by projecting only the window portion after polishing for a predetermined period of time, .

The light transmittance of the windows 104A and 104B may be 20% or more at a wavelength of 400 to 700 nm, and more preferably 30% or more at a wavelength of 670 to 680 nm.

The polishing pad manufacturing method further includes the step of adhering the window 104B having the notched portion at the lower edge portion to the adhesive layer 103. [

In the step of bonding the window 104B to the adhesive layer 103, a part or all of the adhesive layer 103 may be melted and bonded to the window 104B.

At this time, the adhesive of the adhesive layer 103 is impregnated into the notched area of the window 104B.

The melting temperature of the adhesive layer 103 may be 80 to 170 ° C.

The bonding strength between the adhesive layer 103 and the window 104B is excellent and the adhesive layer 103 and the polishing layer 101 and the supporting layer 102 are bonded to each other at a temperature in the range of the melting temperature of the adhesive layer 103, It can be prevented from being deformed or deteriorated. In addition, even if polishing proceeds for a long time, the slurry penetration between the adhesive layer 103 and the window 104B can be prevented.

In order to adhere the window 104B to the adhesive layer 103, it is possible to use heat or vibration, although it is not limited thereto. Specifically, a heat welding or an ultrasonic welding method may be used to adhere the window 104B to the adhesive layer 103 and to fix the window 104B to the first through hole 201. [

The adhesive of the adhesive layer 103 penetrates and fills the notched portion of the window 104B so that the adhesion between the window 104B and the polishing layer 101 The adhesive strength can be improved, and delamination between layers can be prevented.

Meanwhile, a method of manufacturing a polishing pad according to another embodiment may further include the step of providing an adhesive tape to the support layer.

At this time, the adhesive tape is bonded to the other surface opposite to the surface on which the adhesive layer is formed.

The adhesive tape may be a double-sided tape.

The adhesive tape is for allowing the polishing pad manufactured by the polishing pad manufacturing method to be mounted on a platen.

And a fourth through hole passing through the adhesive tape is formed in a predetermined area of the adhesive tape with reference to the first through hole.

The fourth through-hole may be formed in an area where the first through-hole is formed, and the planar area of the fourth through-hole may be smaller than the planar area of the first through-hole.

The third through hole, the second through hole and the fourth through hole are formed at the same time. Specifically, the third through holes, the second through holes, and the fourth through holes may be formed at the same time so that the third through holes, the second through holes, and the fourth through holes correspond to each other.

When the third through holes, the second through holes and the fourth through holes are formed simultaneously so that the third through holes, the second through holes and the fourth through holes correspond to each other, the adhesive layer alone Since there is no adhesive tape, a polishing pad having excellent optical detection accuracy can be produced.

A cutting method according to one embodiment will be described with reference to FIG.

Specifically, FIG. 2 illustrates a third through hole passing through the adhesive layer 103 and a second through hole passing through the support layer 102. Referring to FIG.

A guide member 301 having a cut portion 303 fixed to form the third through hole and the second through hole may be used.

The guide member 301 is inserted into the first through hole passing through the polishing layer 101 and the cut portion 303 is aligned at a predetermined position by the guide member 301, A portion of the adhesive layer 103 and the supporting layer 102 is cut.

The guide member 301 contacts the inner surface of the first through hole to guide the cut portion, and the cut portion can cut the adhesive layer 103 and the support layer 102 at the same time.

A cutting method according to another embodiment will be described with reference to FIG.

Specifically, FIG. 3 illustrates another embodiment in which the third through-hole penetrating the adhesive layer 103 and the second through-hole penetrating the support layer 102 are formed.

The cut portion 304 can be guided by the guide member 302 to form the third through hole and the second through hole.

The guide member 302 is inserted into the first through hole passing through the polishing layer 101 and the cut portion 304 is aligned at a predetermined position by the guide member 302, A portion of the adhesive layer 103 and the supporting layer 102 is cut.

The guide member 302 contacts the inner surface of the first through hole to guide the cut portion, and the cut portion can cut the adhesive layer 103 and the support layer 102 at the same time.

Referring to FIG. 4, a polishing pad according to an embodiment will be described as follows.

The polishing pad has an abrasive layer (101) having a first through hole formed therein; A support layer (102) formed with a second through hole (203) in the region where the first through hole is formed and facing the polishing layer (101); An adhesive layer 103 interposed between the polishing layer 101 and the supporting layer 102, and a third through hole 203 formed in the area where the first through hole is formed; And a window (104B) inserted in the first through hole and having a notched region at a bottom edge portion bonded to the adhesive layer (103), wherein the polishing layer (101) and the supporting layer The first through-hole and the second through-hole 202 are aligned with each other without forming a notch for aligning the first through-hole and the second through-hole 202.

A part or the whole of the adhesive layer 103 is melted and adhered to the window 104B.

Further, the adhesive of the adhesive layer 103 penetrates into the notched area of the window 104B.

The adhesive force of the adhesive layer 103 is filled in the notched area of the window 104B so that the adhesion force between the window 104B and the polishing layer 101 increases as the area of the window 104B increases, And the interlayer separation is prevented.

The polishing pad may be a polishing pad manufactured by the method of manufacturing the polishing pad according to the embodiment.

The polishing pad manufactured by the method of manufacturing a polishing pad according to the above embodiment has an effect of enhancing optical transparency, strengthening interlayer adhesion and preventing delamination.

4 shows a cross section of a polishing pad according to an embodiment. Specifically, FIG. 4 is a cross-sectional view of the polishing pad, in which portions where the window 104B, the third through holes 203, and the second through holes 202 are all present.

W _A in Fig. 4 represents the width of the " upper " window 104B having a notched portion at the lower edge of the polishing pad section, and W _B represents the width of the second through hole 202 or the third through hole And W _C represents the width of the window 104B " bottom " having a notched region in the lower edge portion of the polishing pad cross section.

The W _A may be 10 to 100 mm, but is not limited thereto.

The W _B may be 5 to 95 mm, but is not limited thereto.

On the other hand, W _B is preferably less than W _A.

The W _B may be from 17% to 95% of the W _A , but is not limited thereto.

When the W _B is between 17% and 95% of the W _A , it is possible to prevent the support layer from interfering with the transmission and reflection of the light beam, thereby preventing the window 104 B from being stably fixed to the polishing pad have.

Further, it is preferable that W _C is more than W _B and less than W _A.

The window 104B can be stably fixed at the correct position of the polishing pad without being deflected toward the second through hole 202 or the third through hole 203 when W _C is greater than W _B and less than W _A .

Since the polishing pad has no film or adhesive layer at the bottom of the window 104, the polishing pad has excellent optical transparency.

Referring to FIG. 5, a window having a notched portion in a bottom corner according to an exemplary embodiment will be described.

The window 104B having the notched portion in the lower edge portion can be formed by notching the lower edge portion of the window by rotating the diamond tip while moving the window fixing jig that is not notched, The lower edge of the window is notched using a router device that fixes the jig and moves while rotating the diamond tip.

5 illustrates a cross-section of a window having a notched region at a bottom edge according to one embodiment.

W _D in Fig. 5 represents the height of the window 104B, and W _E represents the height of the notched portion of the window.

The W _D may be 0.5 to 5.0 mm, but is not limited thereto.

When the W _D is 0.5 to 2.5 mm, the W _E may be 10% to 100%, specifically 20% to 70% of the W _D , but is not limited thereto.

When W _D is more than 2.5 mm and 5.0 mm, W _E may be 5% to 90%, more preferably 20% to 50% of W _D , but is not limited thereto.

When the W _D is in the above range, the window 104B can be stably fixed to the polishing pad.

In general, it is necessary to detect when the desired surface flatness or layer thickness has been reached, or when the underlying layer has been exposed, in order to determine whether to abort the polishing. Various techniques exist for in-situ detection of endpoints during the CMP process. For example, an optical monitoring system for in-situ measurement of the uniformity of a layer on a substrate during polishing of the layer may be used. The optical monitoring system may include a light source that directs light toward the substrate during polishing, a detector that measures light reflected from the substrate, and a computer that analyzes the signal from the detector and calculates whether an endpoint has been detected.

101: abrasive layer
102: Support layer
103: Adhesive layer
104A: Window
104B: window with notched area in lower corner
201: first through hole
202: second through hole
203: third through hole
301: Guide member
302: Guide member
303: Cutting section
304:
W _A : Width at the top of the window with a notched area at the bottom edge of the polishing pad section
W _B : Width of the second through hole or the third through hole in the polishing pad section
W _C : width of the bottom of the window with the notched area at the lower edge of the polishing pad section
W _D : height of the window
W _E : height of notched area of window

Claims (15)

(a) providing an abrasive layer;
(b) forming a first through hole through the polishing layer;
(c) providing a support layer opposite the polishing layer;
(d) adhering the abrasive layer and the support layer to each other through the adhesive layer, wherein an adhesive layer is interposed between the abrasive layer and the support layer in which the first through hole is formed;
(e) forming a third through hole passing through the adhesive layer in a predetermined region of the adhesive layer with respect to the first through hole, and a second through hole passing through the support layer in a predetermined region of the support layer;
(f) inserting a window having a notched region in a bottom edge portion into the first through hole; And
And bonding the window to the adhesive layer,
Wherein the step of gluing the window with the adhesive layer comprises the step of melting some or all of the adhesive layer by heat or vibration to cause the adhesive of the adhesive layer to penetrate into the notched area of the window,
A method of manufacturing a polishing pad.
The method according to claim 1,
The third through hole is formed in the region where the first through hole is formed,
Wherein a plane of the third through hole is smaller than a plane of the first through hole,
The second through hole is formed in the region where the first through hole is formed,
And the planar area of the second through-hole is smaller than the planar area of the first through-hole.
3. The method of claim 2,
And the third through hole and the second through hole are simultaneously formed so that the third through hole and the second through hole correspond to each other.
delete delete delete delete The method according to claim 1,
The step (e)
Inserting a guide member into the first through hole;
Aligning the cut portion with a predetermined position by the guide member; And
And cutting the adhesive layer and a part of the supporting layer by the cut portion,
Wherein the cut portion is fixed to the guide member or guided by the guide member.
9. The method of claim 8,
Wherein the guide member is in contact with an inner surface of the first through hole to guide the cut portion.
10. The method of claim 9,
And the cut portion simultaneously cuts the adhesive layer and the support layer.
The method of claim 3,
Providing an adhesive tape to the support layer,
The adhesive tape is adhered to the other surface opposite to the surface on which the adhesive layer is formed,
A fourth through hole passing through the adhesive tape is formed in a predetermined area of the adhesive tape with respect to the first through hole,
And the third through holes, the second through holes, and the fourth through holes are formed at the same time.
The method according to claim 1,
In the step (f), the window having the notched portion at the bottom edge portion may be formed by
The notch-free window fixing jig is rotated while rotating the diamond tip to notch the lower edge of the window,
Wherein the lower edge portion of the window is notched using a router device that fixes the notched window fixing jig and rotates while rotating the diamond tip.
An abrasive layer having a first through hole formed therein;
A second penetrating hole formed in the region where the first through hole is formed, and a supporting layer opposed to the polishing layer;
An adhesive layer interposed between the polishing layer and the supporting layer, the third through-hole being formed in the region where the first through hole is formed; And
And a window inserted into the first through hole and having a notched region at a bottom edge portion adhered to the adhesive layer,
The first through hole and the second through hole are aligned with each other without forming a notch for aligning the first through hole and the second through hole in the polishing layer and the supporting layer,
A part or the whole of the adhesive layer is melted by heat or vibration and the adhesive of the adhesive layer is impregnated into the notched area of the window,
Polishing pad.
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