TW201600242A - Polishing pad conditioner - Google Patents

Abstract

The present invention provides a polishing pad conditioner, which comprises: a substrate including a plurality of recessed parts which are inwardly concaved from the surface of the substrate; a plurality of fixed bases, each fixed base including a bottom part, a top part, at least one groove and one inclined face, the bottom part being arranged in the corresponding recessed part, the top part being connected to the bottom part, the groove being inwardly formed at the top part, the inclined face being formed by inclining from the contact surface of the top part and bottom part toward the groove so as to form an angle and a containing space between the inclined face and the side wall of the recessed part; and a plurality of abrasives disposed in the grooves. When the polishing pad is subjected to conditioning, the polishing pad is rebound to a natural thickness in the containing space without being limited by the abrasive size, so that the cutting depth imposed by the abrasive to the polishing pad can be increased thereby improving the cutting and conditioning effects.

Description

Polishing pad dresser

The present invention relates to a polishing pad conditioner, and more particularly to a polishing pad dresser having a bevel.

Chemical mechanical planarization is an indispensable method in semiconductor manufacturing. It is a polishing pad placed on a stage. The surface is filled with a polishing liquid. The rotation of the stage drives the polishing pad to polish the surface of the wafer. The wafer surface is flattened for subsequent processing. The surface of the polishing pad needs to maintain a certain roughness to maintain the polishing efficiency. However, during the polishing process, the debris generated by polishing the wafer will mix with the polishing liquid to gradually form a hardened layer on the surface of the polishing pad. This results in a decrease in polishing efficiency, which in turn shortens the life of the polishing pad.

Therefore, a polishing pad conditioner is required during the polishing process to continuously trim the surface of the polishing pad to maintain the roughness of the polishing pad surface and prolong the service life of the polishing pad.

As shown in FIG. 10, a conventional polishing pad conditioner includes a substrate 80, a plurality of metal bars 81 and a plurality of abrasives 82. The substrate 80 includes a plurality of holes 83 extending through the substrate 80. The metal bars 81 are mounted. The abrasive 82 is fixed to one end of the metal rod 81 and partially exposed with respect to the substrate 80. When the polishing pad conditioner 8 is used to trim the polishing pad 90, the substrate 80 is pressed against the polishing pad. 90, and partially exposing the surface of the polishing pad 90 through the abrasive material 82 to achieve the purpose of dressing the polishing pad 90, and the depth of cut D will be limited by the size limit of the abrasive material 82, if the abrasive material 82 is used after a certain period of time Not sharp enough will reduce the depth of cut D and affect the efficiency of dressing. Furthermore, the slurry can not achieve sufficient mixing at a limited depth of cut D, thus affecting the efficiency of dressing.

The purpose of this creation is to improve the depth of cut of the existing pad dresser due to the limitation of the size of the abrasive, and the effect of dressing the polishing pad is greatly affected by the wear of the abrasive.

The present invention provides a polishing pad conditioner comprising: a substrate comprising a plurality of concave portions, wherein the inner concave portion is concavely formed on a surface of the substrate, each inner concave portion has a side wall; and the plurality of fixed bases are fixed The base is columnar and includes a bottom portion, a top portion, at least one groove and a sloped surface, the bottom portion is fixedly fixed in the corresponding inner concave portion, the top portion is joined to the bottom portion, and the groove is concavely formed on the top portion The inclined surface is formed obliquely from the contact surface of the top portion and the bottom portion, and the inclined surface and the sidewall of the inner concave portion have an angle and an accommodating space, the angle is 30 degrees to 60 degrees; the plurality of abrasives The mounting is fixed in the recess and forms a tapered structure together with the top.

In the polishing pad dresser of the present invention, when the polishing pad is trimmed, the polishing liquid on the surface of the polishing pad can form a disturbance and turbulence effect in the accommodating space, so that the concentration of the polishing liquid is uniform, and the polishing pad is also in the accommodating space. The rebound back to its natural thickness is no longer limited by the size of the abrasive, so that the abrasive increases the depth of the polishing pad, thereby increasing the cutting and finishing effect.

Preferably, the bottom of each fixed base is mounted through a bonding layer The material of the bonding layer is ceramic material, brazing material, electroplating material, metal material or polymer material; wherein the brazing material is selected from the group consisting of iron, cobalt, nickel, chromium, manganese, A group consisting of bismuth and aluminum; the polymer material is a polyester resin, an epoxy resin, a polyacrylic resin or a phenolic resin.

Preferably, the fixed base is mounted through the bonding layer The fixing method fixed in the corresponding inner concave portion may be a ceramic sintering method, a metal brazing method, a plating method, a metal sintering method or a polymer hardening method.

Preferably, the inner recess is formed on the surface of the substrate. Concentrically arranged; alternatively, the inner recess is radially arranged from the surface of the substrate toward the periphery.

Preferably, the inner concave portion is formed through the base. board.

Preferably, the slope is inclined by a surface treatment Forming, the surface treatment is mechanical grinding, chemical etching or laser processing.

Preferably, each of the abrasives has an end portion, the end portion being located The vertical distance of each abrasive relative to one end of the groove, the end of the abrasive relative to the horizontal plane of the substrate surface, is the degree of exposure of the abrasive, the abrasive being exposed to a degree of 100 to 300 microns.

Preferably, the abrasive comprises at least two different dews The degree of difference, and the difference between the degrees of exposure is 20 to 100 μm; more preferably, the difference between the degrees of exposure is 40 to 60 μm.

Since the thickness of the polishing pad is not uniform, it is made of different abrasives. The degree of exposure matches the arrangement of the fixed base on the substrate, thereby enabling a more uniform trimming effect when the polishing pad is trimmed.

Preferably, the material of the abrasive is rhinestone, natural diamond, polycrystalline diamond or cubic boron nitride.

Preferably, the abrasive has a size of from 30 to 2000 microns; more preferably, from 600 to 1000 microns, and the smallest diameter of the abrasive is greater than 80% of the largest.

Preferably, the abrasive is fixed in the groove of the top by electroplating, sintering or brazing.

Preferably, the abrasive is subjected to a surface treatment to have a specific cutting edge angle, a crystal structure, a tip height and a tip orientation, and the surface processing is mechanical grinding, chemical etching or laser processing. .

Preferably, the abrasive has a cutting edge angle of from 30 to 150 degrees; more preferably, the cutting edge angle is 60 or 90 degrees.

Preferably, the crystal structure of the abrasive is a hexahedron or an octahedron.

Preferably, the substrate is a stainless steel substrate, a mold steel substrate, a metal alloy substrate, a ceramic substrate or a polymer substrate.

Preferably, the number of the inner recesses is between 50 and 300; more preferably between 60 and 100.

Preferably, the inner concave portion has a circular cross section and a cross section having a diameter of 2.6 to 3.6 mm.

Preferably, the fixed base has a cylindrical shape and is made of stainless steel, and the cross section has a diameter of 2.5 to 3.5 mm.

1, 1A, 1B‧‧‧ polishing pad dresser

10, 10A, 10B‧‧‧ substrate

11, 11A, 11B‧‧‧ recess

111, 111A, 111B‧‧‧ side wall

20, 20A, 20B, 20C‧‧‧ fixed base

21, 21A, 21C‧‧‧ bottom

22, 22A, 22C‧‧‧ top

23, 23A, 23C‧‧‧ grooves

24, 24A, 24B, 24C‧‧‧ bevel

25, 25A, 25B‧‧‧ accommodating space

30, 30A, 30B, 30C‧‧‧ abrasives

31, 31A, 31B, 31C‧‧‧ end

40, 40A, 40B‧‧‧ bonding layer

8‧‧‧ polishing pad dresser

80‧‧‧Substrate

81‧‧‧Metal rod

82‧‧‧Abrasive

83‧‧‧ hole

90‧‧‧ polishing pad

D‧‧‧During depth

H, H’‧‧‧ exposure

C‧‧‧Cross section diameter of the fixed base

‧‧‧‧ angle

Θ‧‧‧ cutting edge angle

Figure 1 is a cross-sectional view showing a first embodiment of the creation.

Figure 2 is a partial cross-sectional view showing the first embodiment of the creation.

Figure 3 is a cross-sectional, exploded view of the fixed base of the first embodiment of the present invention.

Fig. 4 is an electron micrograph of the fixed base and the abrasive of the first embodiment of the present invention.

Fig. 5 is a view showing the state of use of the polishing pad according to the first embodiment of the present invention.

Figure 6 is a cross-sectional view showing a second embodiment of the creation.

Figure 7 is a partial cross-sectional view showing a second embodiment of the creation.

Figure 8 is a partial cross-sectional view showing a third embodiment of the creation.

Figure 9 is a cross-sectional, exploded view of the fixed base of the fourth embodiment of the present invention.

FIG. 10 is a schematic view showing the state of use of the polishing pad dresser of the prior art for dressing the polishing pad.

The advantages and features of this creation will be more clearly presented in light of the following description. It should be noted that the drawings are in a simplified form and both use non-precise proportions, and are only used to facilitate and clearly explain the purpose of the present embodiment.

Example 1

As shown in FIG. 1 and FIG. 2, the present invention provides a polishing pad conditioner 1 comprising: a substrate 10, a plurality of fixed bases 20 and a plurality of abrasives 30.

The substrate 10 has a disk shape and includes a plurality of concave portions 11 recessed and formed on the surface of the substrate 10, and each of the concave portions 11 There is a side wall 111. In this embodiment, the substrate 10 is made of stainless steel and has a thickness of 6.35 mm. The number of the inner recesses 11 is 66 and is arranged concentrically on the surface of the substrate 10, wherein the outer ring has 36 inner portions. The number of the circles is 30 (only the schematic is shown in Fig. 1), and the cross section of each of the concave portions 11 is a circular shape having a diameter of 2.6 mm.

The fixed base 20 is fixedly disposed corresponding to the inner recess 11 and including a bottom portion 21, a top portion 22, a recess 23 and a slope 24, in the embodiment, the fixed base 20 is substantially cylindrical and the material is stainless steel, and each fixed base The cross section of the seat 20 has a diameter of 2.5 mm.

The bottom portion 21 of each fixed base 20 is transmitted through a bonding layer 40 The bottom portion 21 of each of the fixing bases 20 is fixed to the corresponding inner recess 11 by metal brazing and through the bonding layer 40, and is fixed in the corresponding inner recessed portion 11. The material of the bonding layer 40 is a brazing material. In this embodiment, the brazing material is aluminum.

The top portion 22 is integrally formed to the bottom portion 21, and The groove 23 is concavely formed on the top portion 22 and disposed at one end opposite to the bottom portion 21, and the top portion 22 has a slope 24 formed obliquely from the contact surface of the top portion 22 and the bottom portion 21 toward the groove 23. The angle between the inclined surface 24 and the side wall 111 of the inner concave portion 11 has an angle α and an accommodating space 25. In the embodiment, the angle α is 45 degrees.

As shown in FIG. 3 and FIG. 4, the abrasive material 30 is fixedly mounted. In the groove 23, a tapered structure is formed together with the top portion. In the embodiment, each of the abrasives 30 is fixedly fixed in the groove 23 by a brazing method and has one end portion 31, and each abrasive material 30 is made of synthetic diamonds and the size is 800 microns, and the end portion 31 of each of the abrasives 30 is located at one end of each of the abrasives 30 with respect to the groove 23, and the vertical distance of the end portion 31 of each of the abrasives 30 relative to the horizontal plane of the surface of the substrate 10 is the exposure of the respective abrasives 30. The degree H of the abrasive 30 is 100 micrometers. Further, the abrasive 30 is subjected to a surface treatment to have a specific cutting edge angle and a crystal structure. In the present embodiment, the cutting edge angle θ of the abrasive 30 is 60 degrees (illustration 3 is only schematic), the crystal structure is a hexahedron, and the exposure of each abrasive 30 and the cross section of each fixed base 20 The ratio of the diameter C is 1:25, and the ratio of the size of the abrasive 30 to the diameter C of the cross section of each fixed base 20 is 8:25.

As shown in Figure 5, the polishing pad conditioner 1 is used for polishing When the pad 90 is trimmed, the polishing liquid on the surface of the polishing pad 90 can form a disturbance and turbulence effect in the accommodating space 25, so that the concentration of the polishing liquid is uniform, and the polishing pad 90 also bounces back in the accommodating space 25. The natural thickness is no longer limited by the size of the abrasive 30, so that the abrasive 30 increases the depth of cut D to the polishing pad 90, thereby increasing the effect of cutting and trimming.

Example 2

As shown in FIG. 6 and FIG. 7 , the polishing pad conditioner 1A of the present embodiment is substantially the same as the first embodiment, except that in the embodiment, the substrate 10A is made of ceramic material. The recessed portion 11A penetrates the substrate 10A, and the number of the inner recessed portions 11A is 100, and is radiated by the center of the substrate 10A toward the periphery (only FIG. 6 is schematically shown), and the diameter of the cross section of each of the inner recessed portions 11A. It is 3.6 mm.

Each of the fixing bases 20A has a cross-sectional surface having a diameter of 3.5 mm, and the bottom portion 21A of each of the fixing bases 20A is polymer-hardened and transmits the knot. The bonding layer 40A is fixed in the corresponding inner recess 11A, and the material of the bonding layer 40A is a polymer material, and the polymer material is an epoxy resin.

Each abrasive 30A is fixedly fixed to the groove by sintering 23A, and the material thereof is cubic boron nitride, the size of which is 2000 micrometers, and the exposure degree H of the abrasive 30A is 300 micrometers, and the cutting edge angle θ of each abrasive 30A is 90 degrees (FIG. 7 is only schematic). The crystal structure is an octahedron, and the ratio of the degree of exposure of each of the abrasives 30A to the diameter C of the cross section of each of the fixed pedestals 20A is 3:35, and the size of the abrasive 30A and the diameter C of the cross section of each of the fixed pedestals 20A The ratio is 4:7.

Example 3

As shown in FIG. 8, the polishing pad conditioner 1B of the present embodiment is substantially the same as that of Embodiment 1, except that in the present embodiment, there are two different abrasives 30B exposure degrees H, H', The difference in the degree of exposure H, H' of the abrasive 30B is 20 to 100 μm, and in the present embodiment, the ratio of the size of the abrasive 30B to the diameter C of the cross section of each of the fixed pedestals 20B is 1:2.

Since the thickness of the polishing pad 90 is not uniform, the exposure degree H, H' of the different abrasives 30B is matched with the arrangement of the fixed base 20B on the substrate 10B, thereby making the polishing pad more uniform. Trimming effect.

Example 4

As shown in FIG. 9, the polishing pad conditioner of the embodiment is substantially the same as that of Embodiment 1, except that the fixing base 20C has at least two grooves 23C and the inclined surface 24C. The groove 23C is concavely formed on the top portion 22C, and the inclined surface 24C is from the top portion 22C and the bottom portion The contact surface of the portion 21C is formed obliquely to the groove 23C, and the abrasive 30C is mounted and fixed in the groove 23C, and each of the abrasives 30C is made of polycrystalline diamond, and its size is 300 micrometers, and each fixed The diameter C of the cross section of the susceptor 20C is 2.5 mm, and the ratio of the size of the abrasive 30C to the diameter C of the cross section of each of the fixed pedestals 20C is 1:8. A larger number of abrasives 30C are mounted on each of the fixed bases 20C, thereby increasing the efficiency of dressing the polishing pads.

Test case

Two identical polishing pads were taken and trimmed with the polishing pad conditioner of Example 1 and the existing polishing pad conditioner (control group, the structure is as described in the prior art), and the two polishing pads at different times were recorded. The thickness was calculated to calculate the polishing efficiency (the polishing pad thickness difference divided by the dressing time), and the results are shown in Table 1.

The polishing pad conditioner of Example 1 has a polishing efficiency of 118 μm/hr, which is 90 μm/hr relative to the existing pad conditioner. The polishing efficiency is increased by 31%. Through the accommodating space between the inclined surface and the inner concave portion, the polishing pad rebounds into the natural thickness of the polishing space, so that the abrasive increases the cutting depth of the polishing pad, so the creation The polishing pad conditioner does improve the cutting and trimming effect with respect to the existing pad dresser.

The above description is only a preferred example of the creation, not the The present invention is not limited to the scope of the present invention, and is not intended to limit the present invention, and is not limited to the scope of the present invention. When an equivalent embodiment of the above-discussed technical content is used to make a modification or modification to the equivalent embodiment, any simple modification of the above embodiment may be made according to the technical essence of the present invention without departing from the technical solution of the present invention. Equivalent changes and modifications are still within the scope of this creative technical solution.

1‧‧‧ polishing pad dresser

10‧‧‧Substrate

20‧‧‧Fixed base

24‧‧‧Bevel

25‧‧‧ accommodating space

30‧‧‧Abrasive

90‧‧‧ polishing pad

D‧‧‧During depth

Claims (10)

A polishing pad conditioner comprising: a substrate comprising a plurality of concave portions, wherein the inner concave portion is concavely formed on a surface of the substrate, each inner concave portion has a side wall; the plurality of fixed bases, each fixed base comprises a a bottom portion, a top portion, at least one groove and a sloped surface, the bottom portion being fixed in the corresponding inner concave portion, the top portion being joined to the bottom portion, wherein the groove is concavely formed on the top portion, the slope surface is from the top portion The bottom contact surface is formed obliquely to the groove, and the inclined surface and the sidewall of the inner recess have an angle and an accommodating space, the angle is 30 degrees to 60 degrees; a plurality of abrasives are fixed on the Inside the groove. The polishing pad conditioner according to claim 1, wherein the bottom of each of the fixing bases is fixed in a corresponding inner concave portion through a bonding layer, and the bonding layer is made of ceramic material, brazing material, plating material, metal. Material or polymer material. The polishing pad conditioner according to claim 1, wherein the bottom of each of the fixing bases is fixed in a corresponding inner concave portion through a bonding layer, and the material of the bonding layer is selected from the group consisting of iron, cobalt, nickel, chromium and manganese. Group of 矽, 矽 and aluminum. The polishing pad conditioner according to claim 1, wherein the bottom of each of the fixing bases is fixed in a corresponding inner concave portion through a bonding layer, and the bonding layer is made of polyester resin, epoxy resin, polyacrylic acid. Resin or phenolic resin. The polishing pad conditioner of claim 1, wherein the inner concave portion is arranged concentrically on a surface of the substrate. A polishing pad conditioner according to claim 1, wherein each of the abrasives has an end portion located at one end of each of the abrasives relative to the groove, and a vertical distance of the end portion relative to a horizontal plane of the substrate surface is an exposure of the abrasive The abrasive has an exposure of from 100 micrometers to 300 micrometers. The polishing pad conditioner of claim 6, wherein the abrasive comprises at least two different degrees of exposure, and the difference between the degrees of exposure is from 20 micrometers to 100 micrometers. A polishing pad conditioner according to claim 1, wherein said abrasive has a specific cutting edge angle of from 30 degrees to 150 degrees. A polishing pad conditioner according to claim 1, wherein the abrasive has a specific crystal structure, and the crystal structure is a hexahedron or an octahedron. A polishing pad conditioner according to any one of claims 1 to 9, wherein the inner recess is formed through the substrate.