TW201829125A - Chemical mechanical polishing pads having a consistent pad surface microtexture - Google Patents

Abstract

The present invention provides pre-conditioned chemical mechanical (CMP) polishing pads comprising a polymer, preferably, a porous polymer having a pad surface microtexture effective for polishing having a series of visibly intersecting arcs on the polishing layer surface, the intersecting arcs having a radius of curvature equal to or greater than half of the radius of curvature of the pad and extending all the way around the surface of the pad in radial symmetry around the center point of the pad wherein the resulting CMP polishing pad has a surface roughness of from 0.01[mu]m to 25[mu]m, Sq. The CMP polishing pads may be made by methods comprising grinding the surface of a CMP polishing pad with a rotary grinder to form the surface microtexture.

Description

   Chemical mechanical polishing pad with consistent pad surface microtexture   

The present invention relates to chemical mechanical polishing (CMP) pads with consistent pad surface microtexture. More specifically, the present invention relates to a CMP polishing pad having a CMP polishing layer of one or more polymers, preferably a porous CMP polishing layer, having a radius, and having a surface roughness of at least 0.01 μm to 25 μm Sq , Or preferably a surface roughness of 1 μm to 15 μm Sq, and a series of obvious cross arcs on the surface of the polishing layer, and the radius of curvature is equal to or greater than half the radius of curvature of the polishing layer, preferably the radius of curvature is equal to The radius of curvature of the polishing layer is half.

The manufacture of polishing pads for chemical mechanical planarization is known to involve forming and curing foam or porous polymers in a mold with the desired diameter of the final polishing pad (such as polyurethane), followed by curing the polymer Demolding and cutting (eg, by cutting) the cured polymer in a direction parallel to the top surface of the mold to form a layer with the desired thickness, and then, for example, by grinding, wiring, or embossing the final surface design into the top of the polishing pad The resulting layer is shaped. Previously, known methods for shaping such layers into polishing pads include layer injection molding, layer extrusion, polishing the layer with a fixed abrasive belt, and / or turning the layer end face to a desired thickness and flatness. These methods have limited ability to achieve uniform pad surface microtexture, which is necessary for polishing the substrate with low defects and uniformly removing material from the substrate. In practice, the method generally forms visible designs, such as grooves with specified width and depth and visible but inconsistent textures. For example, because the die rigidity changes with the die thickness and the cutting blade wears continuously, the cutting process is not reliable for forming the pad surface. Due to continuous tool wear and lathe positioning accuracy, single-point face turning technology has been unable to produce consistent pad surface microtexture. The mat prepared by the injection molding process lacks uniformity due to the inconsistent material flow through the mold; in addition, due to the curing agent and the remaining part of the molding material during injection into the surrounding beam area, especially at high temperatures can be different Flow rate, so when the pad is fixed and cured, the molded article tends to deform.

Polishing methods have also been used to smooth chemical mechanical polishing pads with harder surfaces. In one example of the polishing method, US Patent No. 7,118,461 of West et al. Discloses a smooth pad for chemical mechanical planarization and a method of manufacturing the pad, the method including using a self-pad surface transfer In addition to the material, the abrasive belt polishes or polishes the pad surface. In one example, a smaller abrasive is used for the subsequent polishing step after polishing. The product of the method exhibits improved planarization capabilities compared to the same mat product without smoothing. Unfortunately, although the method of West et al. Can make the pad smooth, it fails to provide a consistent microtexture of the pad surface and cannot be used to treat softer pads (pads or pad polymer matrices according to ASTM D2240-15 (2015) has a Shore D hardness of 40 or less). In addition, the method of West et al. Removed too much material, so that the service life of the resulting polishing pad may be adversely affected. There is still a need to provide a chemical mechanical polishing pad with consistent surface microtexture without limiting pad life.

The adjustment of a chemical mechanical polishing pad is similar to polishing, where the pad is usually adjusted with a rotating grinding wheel having a surface similar to fine sandpaper when in use. After the "run-in" period (during which no pad is used for polishing), such adjustments lead to improved flattening efficiency. It is still desirable to eliminate the run-in period and provide a pre-conditioning pad that can be used immediately for polishing.

The inventors have worked to find a pre-conditioned CMP pad that has consistent pad surface microtexture and improved polishing performance while maintaining its original surface configuration.

1. According to the present invention, there is provided a method of preconditioning a chemical mechanical (CMP) polishing pad having a CMP polishing layer of one or more polymers, the CMP polishing layer having a radius and having a surface roughness of 0.01 μm to 25 μm Sq, And has an effective polishing pad surface micro-texture, the method includes using a rotary grinder to grind the polymeric CMP polishing layer, preferably polyurethane or polyurethane foam CMP polishing layer, better porosity The surface of the CMP polishing layer, where the CMP polishing layer is maintained on the surface of the platform platen, such as by pressure-sensitive adhesive, or preferably vacuum, the rotary grinder includes a rotor and has a surface parallel to the surface of the platform platen A polishing surface made of or substantially parallel and made of a porous abrasive material to form an interface between the surface of the CMP polishing layer and the porous abrasive material.

2. The method according to the invention listed in item 1 above, wherein the radius of the CMP polishing layer extends from its center point to its outer periphery and the diameter of the rotary grinder is equal to or greater than the radius of the CMP polishing layer, or preferably equal to The radius of the CMP polishing layer.

3. The method of the present invention listed in item 2 above, wherein the rotary grinder is positioned so that its periphery directly rests on the center of the CMP polishing layer during grinding.

4. The method of the present invention listed in any one of items 1, 2 or 3 above, wherein the rotary grinder and the CMP polishing layer and the platen platen each rotate during the grinding of the CMP polishing layer. Preferably, the rotation direction of the platform press plate is opposite to that of the rotary grinder.

5. The method of the present invention listed in item 4 above, wherein the rotary grinder rotates at a rate of 50 to 500 rpm, or preferably 150 to 300 rpm, and the platform platen is at 6 to 45 rpm, or preferably Spin at a rate of 8 to 20 rpm.

6. A method according to the invention as listed in any one of items 1, 2, 3, 4 or 5 above, wherein the rotary grinder is positioned above the CMP polishing layer and platform platen during grinding and rotates The grinder is fed downward from a point just above the surface of the CMP polishing layer at a rate of 0.1 to 15 μm / revolution or preferably 0.2 to 10 μm / revolution, even if the interface loss between the surface of the CMP polishing layer and the grinding surface of the rotary grinder And the top surface of the CMP polishing layer is ground.

7. The method of the present invention according to any one of items 1, 2, 3, 4, 5, or 6 above, wherein before grinding, the CMP polishing pad is formed by molding the polymer and cutting the molded polymer to serve as The CMP polishing layer of the pad is formed, or preferably by molding the polymer and cutting the molded polymer to form the CMP polishing layer, followed by stacking the CMP polishing layer on top of the subpad or bottom layer with the same diameter as the CMP polishing layer to form the CMP Polishing pad to form.

8. The method according to the invention as listed in any one of items 1, 2, 3, 4, 5, 6 or 7 above, wherein the porous abrasive material is a composite of a continuous phase of porous material, the The continuous phase of the porous material has been dispersed in its finely powdered non-porous abrasive particles, such as silicon carbide, boron nitride or preferably diamond particles.

9. The method according to the invention as listed in item 8 above, wherein the average pore size of the porous abrasive material is 3 to 240 μm, or preferably 10 to 80 μm.

10. The method according to the invention as listed in any one of items 8 or 9 above, wherein the porous continuous phase of the porous abrasive material comprises ceramic, preferably sintered ceramic, such as alumina or ceria.

11. The method according to the invention as listed in any one of items 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 above, wherein during grinding, the method additionally comprises inert compression Gas or air is intermittently or preferably continuously blown into the interface between the surface of the CMP polishing layer material and the polishing surface of the rotary grinder to impact the porous abrasive material, preferably from a point above the center point of the CMP polishing layer The interface between the surface of the CMP polishing layer material and the grinding surface of the rotary grinder is blown in, or more preferably from the point above the center point of the CMP polishing layer The interface is blown in, and gas or air is blown upward from a point just below the outer periphery of the rotary grinder, for example, where the periphery of the CMP polishing layer and the periphery of the rotary grinder meet to impact the porous abrasive material. Compressed gas or air can also be blown in before or after grinding.

12. The method according to the present invention as listed in any one of items 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11 above, wherein the CMP polishing layer comprises a porous polymer or contains The filler of the porous polymer material has a Shore D hardness according to ASTM D2240-15 (2015) of 20 to 80, or, for example, 40 or less.

13. The method according to the invention as listed in any one of items 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 or 12 above, wherein the CMP polishing layer additionally comprises one or more Non-porous transparent window segments, such as those including non-porous polyurethane with a glass transition temperature (DSC) of 75 to 105 ° C, such as window segments that do not extend past the center point of the CMP polishing layer .

14. The method of the present invention as listed in any one of items 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, or 13 above, wherein the CMP polishing layer is striped And includes a plurality of pores or microelements with an average particle size of 10 to 60 μm, preferably polymerized microspheres.

15. The method of the present invention as listed in item 14 above, wherein the CMP polishing layer has an alternating higher density and lower density endless belt extending outward from the center point of the CMP polishing layer toward its outer periphery.

16. The method according to the invention as listed in item 15 above, wherein the density of the higher density endless belt is 0.01 to 0.2 g / cm ³ higher than that of the lower density endless belt.

17. In another aspect of the invention, the chemical mechanical (CMP) polishing pad includes one or more polymers, preferably a polyurethane CMP polishing layer, preferably a porous CMP polishing layer, CMP The polishing layer has a radius and has a surface roughness of at least 0.01 μm to 25 μm Sq, or preferably a surface roughness of 1 μm to 15 μm Sq, and has a series of obvious crossing arcs on the surface of the polishing layer, and the radius of curvature is equal to or greater than The radius of curvature of the CMP polishing layer is half, preferably the radius of curvature is equal to half of the radius of curvature of the CMP polishing layer. Preferably, the series of obvious crossing arcs always extend around the surface of the polishing layer in a radially symmetrical manner about the center point of the polishing layer.

18. According to the polishing pad of the present invention as listed in item 17 above, the CMP polishing layer has an alternating higher density and lower density endless belt extending outward from the center point of the CMP polishing layer toward its outer periphery.

19. The polishing pad of the present invention as listed in any one of items 17 or 18 above, the polishing pad having one or more non-porous and transparent window sections, such as a glass transition temperature (DSC) of 75 to 105 The non-porous polyurethane sections formed at ℃ do not extend beyond the center point of the CMP polishing pad, where one or more window sections have a maximum size that spans the window, such as a diameter of a circular window , Or the larger of the length or width of the rectangular window, with a peak-to-valley top surface defined by a window of 50 μm or less.

20. The polishing pad according to the present invention as listed in any one of items 17, 18, or 19 above, wherein the thickness of the polishing pad is inclined to become closer to its center point, or inclined to become further away from its center point.

21. A polishing pad according to the invention as listed in any of items 17, 18, 19 or 20 above, wherein the CMP polishing layer is on a non-woven pad such as a polymer, preferably polyurethane, impregnated Wait for stacking on submat or bottom layer.

22. The polishing pad according to the present invention as listed in any one of items 17, 18, 19, 20 or 21 above, wherein the CMP polishing layer includes a porous polymer or a filled porous polymer material according to ASTM D2240- The Shore D hardness of 15 (2015) is 20 to 80, or for example 40 or lower.

Unless otherwise indicated, the conditions of temperature and pressure are ambient temperature and standard pressure. All ranges listed are inclusive and combinable.

Unless otherwise indicated, any term containing parentheses may refer to all terms instead, as if the parentheses did not exist and the term had no parentheses, and a combination of each alternative. Therefore, the term "(poly) isocyanate" refers to isocyanate, polyisocyanate, or mixtures thereof.

All ranges are inclusive and composable. For example, the term "50 to 3000 cp or 100 cp or greater range" will include each of 50 cp to 100 cp, 50 cp to 3000 cp, and 100 cp to 3000 cp.

As used herein, the term "ASTM" refers to the publication of ASTM International, West Conshohocken, PA.

As used herein, the term "thickness change" means the value determined by the maximum change in the thickness of the polishing pad.

As used herein, the term "substantially parallel" refers to the angle formed by the grinding surface of the rotary grinder and the top surface of the CMP polishing layer, or more specifically, extends and terminates parallel to the grinding surface of the rotary grinder The angle defined by the intersection of the first line segment at a point above the center point of the CMP polishing layer and the second line segment extending from the end of the first line segment parallel to the top surface of the platform platen and terminating at the outer periphery of the platform platen , Which is 178 ° to 182 °, or preferably 179 ° to 181 °, wherein the first and second line segments lie in a plane perpendicular to the platen-shaped platen, the plane passing the center point of the CMP polishing layer and The position on the periphery of the grinding surface of the rotary grinder is the point farthest from the center point of the CMP polishing layer.

As used herein, the term "Sq." When used to define surface roughness means the root mean square of a specified number of surface roughness values measured at specified points on the surface of a given CMP polishing layer.

As used herein, the term "surface roughness" means a value determined by measuring the surface height relative to a best-fit plane, which represents a surface parallel to the top surface of a given CMP polishing layer and located at a given CMP The horizontal surface on the top surface of the polishing layer at any given point on the top surface; Svk refers to the valley depth measured in the low region; and Spk refers to the peak measured in the high region. The acceptable surface roughness range is 0.01 μm to 25 μm Sq, or preferably 1 μm to 15 μm Sq.

As used herein, the term "wt.%" Means weight percent.

1‧‧‧Platform platen

2‧‧‧CMP polishing layer or pad

3‧‧‧window

4‧‧‧Rotary grinding machine assembly / rotary grinding machine (rotor) assembly

5‧‧‧Porous abrasive materials

Figure 1 depicts an embodiment of the rotary grinder of the present invention and shows a flat platen and a CMP polishing layer containing a transparent window.

2 depicts a CMP polishing layer with a uniform groove microtexture defined by crossed arcs on the surface, where the radius of curvature of each arc is equal to or slightly greater than the radius of the CMP polishing layer.

According to the present invention, a CMP polishing pad having significantly improved defectivity performance is formed by a polishing method that improves the surface microtexture of the CMP polishing layer, including the surface microtexture of the top surface of the CMP polishing pad and the polishing layer. The uniform surface microtexture of the CMP polishing pad of the present invention is characterized by a series of crossed arcs in the surface of the CMP polishing layer and has the same radius of curvature as the circle defined by the outer periphery of the polishing surface of the rotary grinder, and is characterized by the CMP polishing layer The surface roughness on the upper surface is 0.01 to 25 μm, Sq. The inventors have found that the CMP polishing layers manufactured according to the present invention perform well with little or no adjustment, that is, they are pre-adjusted. In addition, the microtexture of the pad surface of the CMP polishing layer of the present invention enables enhanced polishing of the substrate. The pad shape of the CMP polishing pad of the present invention is less irregular than the same pad manufactured by molding and cutting, which may cause surface defects of the chemical mechanical polishing pad, such as chiseling, and blistering of window materials, windows The material is softer than the rest of the CMP polishing layer. In addition, the pads of the present invention are subject to less negative effects due to the deformation of the polishing layer during pad stacking, during which two or more pad layers are linearly corrugated by nip groups separated by a fixed distance. This is especially important for soft and compressible CMP polishing layers. In addition, the pad of the present invention spans the surface of the substrate, such as the surface of a semiconductor or wafer, with optimized surface microtexture, less defects, and improved uniform material removal.

The inventors have found that polishing with a porous abrasive material can polish but does not foul the polishing medium and does not damage the CMP polishing layer substrate. The pores in the porous abrasive material are large enough to store the particles removed from the CMP polishing layer substrate; and the porosity of the porous abrasive material is sufficient to store the material body removed during grinding. Preferably, blowing compressed air through the interface of the surface of the CMP polishing layer material (below) and the polishing surface of the rotary grinder (above) and the CMP polishing layer substrate further helps to remove abrasive particles and prevent fouling of the polishing equipment.

The porous abrasive material is preferably zigzag and includes discontinuous portions or gaps at the periphery of the rotary grinder. Such gaps help to cool the abrasive surface of the porous abrasive material and the CMP polishing layer substrate during grinding and remove abrasive particles during processing. The gap also allows compressed gas or air to be blown into the interface between the surface of the CMP polishing layer and the grinding surface of the rotary grinder to remove abrasive particles during grinding.

The method of the present invention can be changed to compensate for undesired CMP substrate profile wear, such as in the case of inconsistent profile wear caused by the CMP process, such as too little or too much removal at the edge of the substrate. This in turn can extend the life of the pad. In such methods, the grinding surface of the rotary grinder is adjusted so that it is substantially parallel but not exactly parallel to the top surface of the flat platen or CMP polishing layer. For example, the grinding surface of the rotary grinder can be adjusted to produce a center thickness (the angle between the grinding surface of the rotary grinder and the radius of the platform platen exceeds 180 °, and the plane of the angle is perpendicular to the platform platen And by the center point of the CMP polishing layer and the peripheral edge of the grinding surface of the rotary grinder farthest from the center point of the CMP polishing layer) or the center is thin (angle less than 180 °).

The method of the present invention can be carried out in a humid environment, such as combining water or grinding an aqueous slurry, such as silica or ceria slurry.

Since the size of the components of the rotary grinder can be changed, the method of the present invention can be scaled to fit CMP polishing layers of various sizes. According to the method of the present invention, the flat platen should be larger than the CMP polishing layer or preferably have a size equal to the radius of the CMP polishing layer or within a radius longer than the radius of the CMP polishing layer. The method can therefore be scaled to handle CMP polishing layers with a radius of 100 mm to 610 mm.

The method of the present invention removes the top surface of the CMP polishing layer to form a uniform pad surface microtexture and can be used to remove 1 to 300 μm from the top surface of the CMP polishing layer, or preferably 15 to 150 μm, or more preferably 25 μm or more Multi-pad material.

The method of the present invention can provide a CMP polishing layer or pad free from defects caused by window swell and cutting. Therefore, according to the present invention, the CMP polishing layer can form a porous molded article having a desired diameter or radius by molding the polymer, which diameter or radius will be the size of the pad manufactured therefrom; The desired thickness, which will be the target thickness of the pad manufactured according to the present invention; an abrasive pad or CMP polishing layer is then formed on its polishing surface to provide the desired pad surface microtexture.

The method of the present invention can be performed on a single layer or individual pads, as well as on stacked pads with sub-pad layers. Preferably, in the case of stacked pads, a grinding method is performed after the pads are stacked, so that grinding can help eliminate distortion in the stacked pads.

The method of the present invention includes forming a groove in the pad after grinding, such as by turning the pad.

Suitable CMP polishing layers used in accordance with the method of the present invention preferably include porous polymers or fillers containing porous polymeric materials, which have a Shore D hardness of 20 to 80 according to ASTM D2240-15 (2015).

The method of the present invention can be performed on any pad, including those made from relatively soft polymers, and has been found to be of particular use in the treatment of soft pads with a Shore D hardness of 40 or less. The pad may preferably be porous. The pores may be provided by spaces in the pad polymer matrix or pore-forming agents or microelements or fillers containing voids or pores.

Suitable CMP polishing layers for use in accordance with the method of the present invention may further include one or more non-porous transparent window sections, such as those including non-porous polyurethane with a glass transition temperature (DSC) of 75 to 105 ° C Window segments, such as those that do not extend past the center point of the CMP polishing layer. In this type of CMP polishing layer, one or more window sections have a maximum size spanning the window, such as the diameter of a circular window, or the greater of the length or width of a rectangular window, which is a window thickness of 50 μm or less Changes define the top surface.

In addition, suitable CMP polishing layers for use with the method of the present invention may include a plurality of pores or microelements with an average particle size of 10 to 60 μm, preferably polymerized microspheres.

According to the present invention, a soft CMP polishing layer with a Shore D hardness of 40 or less on the polished surface also has a uniform pad surface microtexture, which contains a series of distinct cross arcs on the polished surface and a radius of curvature equal to or greater than that of the polishing layer The radius of, preferably the radius of curvature is equal to the radius of the polishing layer. Preferably, the series of obvious crossing arcs always extend radially symmetrically about the surface of the polishing layer about the surface of the polishing layer.

As shown in FIG. 1, the method of the present invention is performed on the surface of a platform-type platen ( 1 ) having a vacuum port, not shown. The CMP polishing layer or pad ( 2 ) is placed on the flat platen ( 1 ) so that the center point of the flat platen ( 1 ) is aligned with the center point of the CMP polishing layer ( 2 ). The flat platen ( 1 ) in FIG. 1 has a vacuum exhaust port (not shown) to hold the CMP polishing layer ( 2 ) in place. In FIG. 1, the CMP polishing layer ( 2 ) has a window ( 3 ). The grinding mechanism of the present invention includes a rotary grinding machine (rotor) assembly ( 4 ) or a rotor, and a grinding medium including a porous grinding material ( 5 ) is attached to the lower surface of the peripheral edge, as shown in the figure, The grinding medium is arranged in a plurality of sections extending around the lower surface of the circumference of the rotor ( 4 ). There is a small gap between the sections of porous abrasive material. In FIG. 1, the rotary grinder assembly ( 4 ) is positioned as needed so that its periphery is just above the center point of the CMP polishing layer ( 2 ); in addition, the rotary grinder assembly ( 4 ) has the required size to So that its diameter is approximately equal to the radius of the CMP polishing layer ( 2 ).

The grinding equipment used in the method of the present invention includes a rotary grinding machine assembly and its drive housing, including a motor and a gear link mechanism; and a platform-type pressure plate. Additionally, the apparatus includes a conduit for directing compressed gas or air to the interface of the porous abrasive material attached to the rotary grinder assembly and the CMP polishing layer. The entire device is enclosed in a sealed enclosure, where the humidity is preferably controlled at RH 50% or lower.

The rotary grinder assembly of the grinding equipment used in the method of the present invention rotates on a vertical shaft that extends into the drive housing and is connected to the drive housing via a mechanical linkage mechanism such as a gear or transmission belt Motor or rotary actuator. The drive housing additionally contains a radial array of two or more pneumatic or electronic actuators located above the adjacent rotary grinder assembly, whereby the rotary grinder assembly can be used, for example, by slowly increasing it at a slow rate Feed downwards and obliquely to raise or lower. The actuator additionally enables the tilting of the rotary grinder assembly so that its grinding surface is substantially but not exactly parallel to the top surface of the platform platen; this enables grinding to form a thick center or thin center pad.

The rotary grinder assembly contains an array of clamps, fasteners, or lateral spring-loaded snap rings, where the ring of porous abrasive material is tightly fitted on the lower surface of the rotary grinder assembly.

The porous abrasive material is carried on a single support ring that fits into or is attached to the lower surface of the rotary grinder assembly. The porous abrasive material may include a radial array of turning sections at the lower end, usually 10 to 40 porous abrasive material sections with a gap in the middle; or a perforation made of porous abrasive material with periodic perforations in the middle ring. The gap or perforation allows compressed gas or air to be blown into the surface of the CMP polishing layer and the interface of the CMP polishing layer to clean the porous abrasive material before, during, or after use.

The pad surface microtexture of the CMP polishing layer manufactured according to the present invention is proportional to the surface roughness of the CMP polishing layer and the size of the fine powdery non-porous abrasive particles on the polishing surface of the rotary grinder. For example, the surface roughness of 1 μm Sq. Corresponds to fine powdery nonporous abrasive particles with an average particle diameter (X50) slightly lower than 1 μm.

The platform platen in the apparatus of the present invention contains a plurality of small holes, for example, small holes with a diameter of 0.5 to 5 mm, and these small holes are connected to a vacuum through the platen. The holes may be arranged in any suitable manner that holds the CMP polishing layer substrate in place during grinding, such as a series of spokes extending outward from the center point of the platform platen or a series of concentric rings.

Example: In the following example, unless otherwise stated, all pressure units are standard pressure (~ 101kPa) and all temperature units are room temperature (21-23 ° C).

Example 1: Two forms of VP5000 ^™ CMP polishing layer or pad (Dow Chemical, Midland, MI (Dow)) with a radius of 330 mm (13 ") were used for testing. The pad has no window. In Example 1-1, the CMP polishing layer includes a single porous polyurethane pad having a thickness of 2.03 mm (80 mils), and wherein the Shore D of the polyurethane The hardness is 64.9. In Example 1-2, the CMP polishing layer includes stacking the same polyurethane pad of Example 1-1 to SUBA IV ^TM made of polyester felt (Dow) using a pressure-sensitive adhesive Stacked pads from the sub-pads.

The comparisons in Examples 1-A and 1-B are the same pads as in Examples 1-1 and 1-2, respectively, but were not processed according to the method of the present invention: the stacked pads have SIV sub-pads.

All pads have 1010 grooves (a pattern of concentric circular grooves with a depth of 0.0768cm (0.030 ") x 0.0511cm (0.020") width x 0.307cm (0.120 "), and no windows.

The porous abrasive material is a vitrified porous diamond abrasive with an average grinding size of 151 μm. To grind the substrate, the rotary grinder assembly is positioned parallel to the top of the platform platen and rotates counterclockwise at 284 rpm and the platform aluminum platen rotates clockwise at 8 rpm. From the point where the porous abrasive material just starts to touch the CMP polishing layer substrate, the rotary grinder assembly is fed downward toward the platform platen at a rate of 5.8 μm (0.0002 ") increments per 3 pad revolutions. Here During this period, compressed dry air (CDA) was blown into the interface between the surface of the porous abrasive material and the surface of the CMP polishing layer from two nozzles, one of which was located just above the center point of the CMP polishing layer and the other was located in the porous The back side of the abrasive material is about 210mm (8.25 ") from the center of the pad. Grinding lasts about 5 minutes.

In the polishing test, the removal rate, non-uniformity, and chatter marks (defectiveness) of the pad from Example 1 were evaluated as follows: Removal rate: On a 200 mm-sized tetraethoxysilicate (TEOS) substrate, borrow It was determined by flattening the substrate using an ILD3225 ^TM fumed silica aqueous slurry (Dow) using a specified pad and a flow rate of 200 ml / min. Using the Mirra ^TM polishing tool (Applied Materials, Santa Clara, CA), at 93/87 platen / substrate carrier rpm, the polishing pressure was 0.11, 0.21, and 0.32 kg / cm ² (1.5, 3.0, 4.5 psi) the pressure varies. Before the test, a SAESOL ^TM 8031C1 disc (sintered diamond dust surface, 10.16 cm diameter, Saesol Diamond Ind. Co., Ltd., Korea) was used as the regulator, at 3.2 kg (7 lb ) Adjust all polishing pads for 40 minutes. During the test, continue to make the same adjustments to the pad. A total of 18 wafers were tested per pad and averaged.

Non-uniformity: For the same TEOS substrate flattened in the removal rate test and measured in the manner disclosed in the removal rate test, the exception is that the data is obtained by observing the thickness variation within the wafer. A total of 18 wafers were tested per pad and averaged.

Jitter or defect count: The same TEOS substrate that was planarized in the removal rate test was measured in the manner disclosed in the removal rate test, with the exception that the data was obtained by observing the total number of CMP defects. A total of 18 wafers were tested per pad and averaged.

The resulting pad has a pad surface micro-texture that includes a cross-arc with a radius of curvature equal to the radius of curvature of the circumference of the rotary grinder assembly. In addition, as shown in Table 1 below, the pads of Examples 1-1 and 1-2 of the present invention produced the same flattening rate on the substrate as the comparative pads of Examples 1-A (single) and 1-B (stacked); meanwhile, Compared with the pads of Comparative Examples 1-A and 1-B that have not undergone the polishing method of the present invention, the pads of Examples 1-1 and 1-2 of the present invention significantly reduce the degree of defects in the substrate and the chatter marks.

Example 2: A 419 mm (16.5 ") radius IC1000 ^TM single layer polyurethane pad (Dow) with a hardness of 61.0 Shore D was used for the test, wherein the pad of Example 2 was treated in the same manner as Example 1 above, with the exception The point is that the rotary grinder assembly is fed downward toward the platen platen at a rate of 20.3 μm (0.0007 ") increments per 8 pad revolutions and the grinding is continued for 5.5 minutes. The pad of Comparative Example 2-A is the same pad as Example 2 that was not treated according to the method of the present invention.

14 pads were tested and the average result of the thickness change was reported. The thickness change was tested as follows: Thickness change: measured on the entire surface of the polishing pad using a coordinate measuring machine. Each pad collects a total of 9 discrete measurement locations from the center to the edge of the pad. The thickness change is calculated by subtracting the thinnest measurement value from the thickest measurement value. The results are shown in Table 2 below.

The resulting pad of the present invention has a characteristic pad surface microtexture. The pad of Example 2 of the present invention has a smaller average thickness variation and therefore its shape is more consistent than the pad of Comparative Example 2-A.

Example 3: Compared to the commercially available IC1000 ^TM pad (Dow), the surface roughness of the pad of Example 2 above was measured. The pad of Comparative Example 2 is the same pad as Example 2-A, but was not treated according to the method of the present invention.

On each of the 2 pads, the surface roughness was measured at 5 equally spaced points from the center to the edge of the pad and the average results of the surface roughness are reported in Table 3 below.

As shown in Table 3 above, the CMP polishing layer of the present invention in Example 3 has a defined pad surface microtexture and a determined surface roughness characterized by reduced valley depth.

Example 3: Using a large 419mm (16.5 ") radius IK2060H ^TM single layer polyurethane pad (Dow) with a hardness of 33.0 Shore D, using Example 3-1 treated in the same manner as Example 2 above , 3-2, 3-3 pads are tested, the exception is to feed the rotary grinder assembly toward the platform platen and stop at different heights to achieve lightness (least grinding, most such as self-grinding surface) The highest peak measurement on the pad surface that touched the pad first was stopped after removing the 12.7μm (0.5 mil) pad), medium (e.g. stopped after removing the 50.8μm (2 mil) pad from the highest peak measurement on the pad surface) And complete surface microtexturing (maximum grinding, such as stopping after removing the 101.6 μm (4 mil) pad from the highest peak measurement on the pad surface.) Comparative Example 3-A pads are the same as Examples 3-1, 3-2 and 3-3 The same pad, but not treated according to the method of the present invention.

All pads have 1010 grooves (a pattern of concentric circular grooves with a depth of 0.0768cm (0.030 ") x 0.0511cm (0.020") width x 0.307cm (0.120 "), and no windows.

In the polishing test, the removal rate and defect degree of the pad from Example 3 were evaluated as follows: Removal rate: On a 200 mm-sized tetraethoxysilicate (TEOS) substrate, by using the specified pad and 200 ml / The AP5105 ^TM silica aqueous slurry (Dow) was used to flatten the substrate at the min flow rate. Using a Mirra ^™ polishing tool (Applied Materials, Santa Clara, California), the polishing pressure was constant at a pressure of 0.11 kg / cm ² (1.5 psi) at 93/87 platen / substrate carrier rpm. Before wafer polishing, no pad adjustment was performed. Using a SAESOL ^™ 8031C1 disc (sintered diamond dust surface, 10.16 cm diameter, Korea Sesol Diamond Co., Ltd.) as an adjustment machine, all polishing pads were completely adjusted in situ at 3.2 kg (7 pounds). During the test, continue to make the same adjustments to the pad. Each pad tests a total of 76 wafers and measures selected subgroups of 6 wafers (No. 1, No. 7, No. 13, No. 24, No. 50 and No. 76 wafers); The measured subgroups obtain average values and report defect counts and removal rates below. The measured value of wafer No. 24 is also reported below.

Defect count: For the same TEOS substrate flattened in the removal rate test and measured in the manner disclosed in the removal rate test, the exception is that the data is obtained by observing the total number of CMP defects. Each pad tested a total of 76 wafers, measured a subset of 6 wafers, and obtained an average value.

As shown in Table 4 below, the pads of Examples 3-2 and 3-3 of the present invention produced a significantly higher planarization rate on the substrate than the comparative pad of Example 3-A; at the same time, as compared to those not subjected to the grinding method of the present invention The pads of Comparative Example 3-A and the pads of Examples 3-2 and 3-3 of the present invention significantly reduce the degree of defects in the substrate. Examples 3-2 and 3-3 showed more grinding of the pad compared to Example 3-1, improving its polishing performance, at least up to about 51 μm of material removed from the pad surface.

Claims (10)

    A chemical mechanical (CMP) polishing pad, including a CMP polishing layer of one or more polymers, the CMP polishing layer has a radius, has a surface roughness of 0.01 μm to 25 μm Sq and has a series of obvious on the surface of the polishing layer , The radius of curvature of the cross arc is equal to or greater than half of the radius of curvature of the polishing layer and always around the surface of the polishing layer in a radially symmetrical manner about the center point of the polishing layer extend.         A chemical mechanical (CMP) polishing pad as described in item 1 of the patent application scope includes a porous CMP polishing layer of one or more polymers.         A chemical mechanical (CMP) polishing pad as described in item 2 of the patent application range, wherein the CMP polishing layer includes a porous polymer or a filled porous polymer material according to Shore D of ASTM D2240-15 (2015) The hardness is 20 to 80.         A chemical mechanical (CMP) polishing pad as described in item 3 of the patent application range, wherein the CMP polishing layer includes a porous polymer or a filled porous polymer material according to Shore D of ASTM D2240-15 (2015) The hardness is 40 or lower.         A chemical mechanical (CMP) polishing pad as described in item 1 of the patent scope, wherein the one or more polymers are polyurethanes.         The chemical mechanical (CMP) polishing pad as described in item 1 of the patent application range, wherein the radius of curvature of the cross-arc is equal to half of the radius of curvature of the CMP polishing layer.         A chemical mechanical (CMP) polishing pad as described in item 1 of the patent application range, wherein the CMP polishing layer has alternating higher density and lower extension extending outward from the center point of the CMP polishing layer toward its outer periphery Density of the endless belt.         The chemical mechanical (CMP) polishing pad of claim 1, wherein the polishing pad has one or more non-porous and transparent window sections that do not extend beyond the center point of the CMP polishing pad , Wherein the one or more window sections have a top surface defined by a window thickness variation that spans the maximum dimension of the window of 50 μm or less.         The chemical mechanical (CMP) polishing pad as described in item 1 of the patent application scope, wherein the CMP polishing layer is stacked on the subpad or the bottom layer.         A chemical mechanical (CMP) polishing pad as described in item 9 of the patent application scope, wherein the sub-pad or bottom layer is a polymer-impregnated non-woven pad.