TW201819110A - Apparatus for shaping the surface of chemical mechanical polishing pads - Google Patents

Abstract

The present invention provides apparatus for pre-conditioning polymeric, preferably, porous polymeric, chemical mechanical (CMP) polishing pads or layers and polishing a substrate that comprise a rotary grinder assembly having a rotor with a grinding surface of a porous abrasive material, a flat bed platen for holding the CMP polishing pad or layer in place so that the grinding surface of the rotary grinder is disposed above and parallel to the surface of the flat bed platen to form an interface of the surface of the CMP polishing layer and the porous abrasive material, and a substrate holder located above and parallel to a top surface of the flat bed platen and to which a CMP substrate is attached, thereby creating a polishing interface between the surface of the substrate and the CMP polishing layer wherein the substrate holder rotates independently from the rotary grinder assembly and the flat bed platen.

Description

   Device for forming surface of chemical mechanical polishing pad   

The present invention relates to a device for providing a pad surface with a microtextured structure to a polishing pad, such as a polymer pad, which is used for chemical mechanical planarization (CMP) of substrates such as semiconductor substrates, magnetic substrates, and optical substrates. ); And a method of using the device. More specifically, the present invention relates to a device for polishing the surface of a CMP polishing layer, the device comprising: a rotary grinder having a polishing surface of a porous abrasive material to form a surface of the CMP polishing layer and porous polishing The interface of the material surface; and a platform platen for holding the CMP polishing layer in place.

The manufacture of polishing pads for chemical mechanical planarization is known to involve shaping and curing a foam or porous polymer in a mold having the desired diameter of the final polishing pad, such as a polyurethane, followed by curing the polymer Demold and cut (eg, by cutting) the cured polymer in a direction parallel to the top surface of the mold to form a layer of the desired thickness, and then shape the resulting layer, such as by grinding, routing, or pressing the final surface design Printed on top of polishing pad. Previously, known methods for forming such layers into polishing pads include layer injection molding, layer extrusion, polishing the layer with a fixed abrasive tape, and / or turning the end faces of the layer to a desired thickness and flatness. These methods have limited ability to achieve a uniform pad surface micro-textured structure that is necessary to reduce the degree of defects in the polished substrate and uniformly remove material from the substrate. In fact, the methods often produce visible designs, such as grooves with a specified width and depth, and visible but inconsistent textures. For example, because the mold stiffness changes with the thickness of the mold and the cutting inserts are continuously worn, the cutting process is not reliable due to the mat surface forming. Due to continuous tool wear and lathe positioning accuracy, the single-point end-face turning technology has been unable to produce a consistent micro-textured surface of the pad surface. The pad produced by the injection molding process lacks uniformity due to the inconsistent material flow through the mold; in addition, the curable molding material and the remainder of the molding material can be injected during the injection into the surrounding area, especially at high temperatures. It flows at different rates, 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 having a harder surface. In one example of a polishing method, U.S. Patent No. 7,118,461 to West et al. Discloses a smooth pad for chemical mechanical planarization and a method of manufacturing the pad, the method comprising polishing or polishing the surface of the pad with an abrasive tape to Remove material from pad surface. In one example, a smaller polishing belt is used for subsequent polishing steps after polishing. The products of the method exhibit improved planarization capabilities compared to the same pad products without polishing. Unfortunately, although West et al.'S method can smooth the pad, it fails to provide a consistent pad surface microtexture and cannot be used to process softer pads (pads or polymer mat substrates according to ASTM D2240-15 (2015 ) Has a Shore D hardness of 40 or less). In addition, the West et al. Method removes so much material that the useful life of the resulting polishing pad may be adversely affected. It is still desirable to provide a chemical mechanical polishing pad having a uniform surface microtexture structure without limiting the life of the pad.

The conditioning of chemical mechanical polishing pads is similar to polishing, where the pads are typically conditioned with a rotating abrasive wheel having a surface similar to fine sandpaper in use. After the 'run-in' period (during which no pad is used for polishing), such conditioning improves the flattening efficiency. It is still desirable to eliminate the run-in period and provide a preconditioned pad that can be used immediately for polishing.

The present inventors have devoted to discovering a device for manufacturing a pre-conditioned CMP pad having a uniform micro-textured surface of the pad surface while maintaining its original surface configuration.

1. According to the present invention, there is provided a polyurethane (polyurethane or polyurethane foam) chemical mechanical mechanism having a pre-conditioned polymer (preferably a porous polymer) having a micro-textured structure effective for polishing a pad surface. (CMP) A device for a polishing pad or layer includes: a rotary grinder assembly having a wheel or rotor having a polishing surface of a porous abrasive material; and a means for holding the CMP polishing layer in place, such as By means of a pressure-sensitive adhesive (or preferably a vacuum) platen platen, the grinding surface of the rotary grinder is placed above the surface of the platen platen and parallel or substantially parallel to the surface of the platen platen to form a CMP The interface between the surface of the polishing layer and the surface of the porous abrasive material.

2. The device according to the present invention as described in item 1 above, wherein said CMP polishing layer has a radius extending from its center point to its outer periphery and a grinding surface of a wheel or rotor of said rotary grinder assembly The diameter of is equal to or greater than the radius of the CMP polishing layer, and preferably equal to the radius of the CMP polishing layer.

3. The device according to the present invention as described in item 2 above, wherein the wheel or rotor of the rotary grinder assembly is positioned such that during grinding, the outer periphery of the grinding surface rests directly on the center of the CMP polishing layer on.

4. The device according to any one of items 1, 2 or 3 above, wherein the rotor or rotor of the rotary grinder assembly and the CMP polishing layer and the platen platen are each on the CMP polishing layer. Rotate during grinding. Preferably, the rotation direction of the platen platen is opposite to that of the rotary grinder assembly.

5. The device according to the invention as described in item 4 above, wherein the wheel or rotor of the rotary grinder assembly rotates at a rate of 50 to 500 rpm or preferably 150 to 300 rpm, and the platform type The platen is rotated at a rate of 6 to 45 rpm, or preferably 8 to 20 rpm.

6. The device according to any one of items 1, 2, 3, 4 or 5 above, wherein a wheel or a rotor of the rotary grinder assembly is positioned on the CMP polishing layer during grinding and Above the platen-type platen, and the rotary grinder feeds down from a point just above the surface of the CMP polishing layer at a rate of 0.1 to 15 microns / revolution or preferably 0.2 to 10 microns / revolution, that is, to polish the CMP The interface between the layer surface and the surface of the porous abrasive material shrinks.

7. The apparatus according to any one of items 1, 2, 3, 4, 5, or 6 above, wherein the rotary grinder assembly includes a motor or rotary actuator (such as an electric motor) Or servomotors), and vertically mounted axles (such as by gears or drive belts) connected to and driven by a motor or rotary actuator, such as by gears or drive belts Inside and at its lower end, it is connected to a wheel or rotor by a mechanical linkage such as a gear or drive belt so that it rotates at a desired number of revolutions per minute (rpm).

8. The device according to the present invention as described in item 7 above, wherein in the driving housing, the vertically arranged wheel axle comprises a ball screw or a secondary servo motor, and the ball screw or the secondary servo motor is located between the wheel axle and the The connection of the motor or the rotary actuator, the mechanical connection of the wheel and the rotor or the rotor, or these two positions, so that the rotor or the rotor of the rotary grinder assembly can be lowered at a set increasing rate. feed.

9. A device according to the invention according to item 8 above, wherein the runner or rotor comprises one or more eccentric mechanisms, a pneumatic drive (such as a cylinder), an electronic actuator or a motor actuator, such as a servo motor Three to eight such actuators are preferably arranged in a radial array around the runner or rotor, whereby the runner or rotor can be tilted so that its abrasive surface is substantially parallel to the top surface of the platform platen, This allows grinding to produce a CMP polishing layer or pad with a thick or thin center.

10. The device according to the present invention, wherein a wheel or rotor of said rotary grinder assembly has a porous abrasive material grinding medium preferably carried on a single washer, said grinding medium being attached to its lower peripheral surface, such as by A radial array of clips, fasteners or a lateral spring-loaded snap ring is located on the lower surface of the rotary grinder assembly and fits tightly with the periphery of the porous abrasive material ring.

11. The device according to the invention according to item 11 above, wherein the porous abrasive material grinding medium is arranged in a plurality of sections, the sections extending around the lower surface of the peripheral edge of the rotary grinder assembly and There is a gap between the sections.

12. The device of the present invention according to any one of the above 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11, wherein the porous abrasive material is a composite of a porous continuous phase The porous continuous phase has been dispersed in its fine powdery non-porous abrasive particles, such as boron nitride or preferably diamond particles.

13. The device according to the invention according to item 12 above, wherein the porous continuous phase of the porous abrasive material has an average pore diameter of 3 to 240 μm or preferably 10 to 80 μm.

14. The device according to any one of items 8 or 9 above, wherein the porous continuous phase of the porous abrasive material comprises a ceramic, preferably a sintered ceramic, such as alumina or cerium dioxide.

15. The device according to any one of items 1 to 14 above, wherein the platform platen includes a plurality of small holes, such as small holes having a diameter of 0.5 to 5 mm, penetrating the platen and communicating with the vacuum. The holes may be arranged by any suitable means to keep the CMP polishing layer substrate in place during grinding, such as along a series of spokes extending outwardly from the center point of the platen platen or in a series of concentric rings.

16. A device according to the invention according to any one of items 1 to 15 above, further comprising a duct, hose, nozzle or valve for intermittently or preferably continuously blowing compressed inert gas or air, And positioned to blow an inert gas or air into the interface between the surface of the CMP polishing layer material and the surface of the porous abrasive material in order to impact the porous abrasive material during grinding, preferably from a point adjacent to the center point of the CMP polishing layer on the platen platen Blow through the interface of the CMP polishing layer and the porous abrasive material, or more preferably, the conduit, hose, nozzle or valve is positioned to blow an inert gas or air from a point adjacent to the center point of the CMP polishing layer on the platform platen Traverses the interface of the CMP polishing layer with the porous abrasive material to impact the porous abrasive material; and separately includes a second conduit, hose, or valve for blowing compressed pressure upward from a point just below the peripheral edge of the rotary grinder assembly An inert gas or air to impact the porous abrasive material during grinding, for example, where the periphery of the CMP polishing layer and the periphery of the rotary grinder meet.

17. The device of the invention according to any one of items 1 to 16 above, the device further comprising a substrate holder positioned above the top surface of the platform platen and parallel to the platform platen The top surface of the substrate so as not to overlap the area where the rotary grinder assembly is placed and the area where the CMP substrate (such as a semiconductor substrate or wafer, magnetic substrate or optical substrate) is attached (eg, clamped). A polishing interface is generated between the surface of the CMP polishing layer and the substrate holder, which rotates independently of the rotary grinder assembly and the platen platen, for example, at an individual speed of 1 to 200 rpm or preferably 10 to 100 rpm.

18. The device of the present invention as described in item 17 above, wherein the diameter of the substrate holder is smaller than the radius of the CMP polishing layer or pad held by the platen platen, and further wherein the substrate holder is mechanically Connected to or mounted on a first actuator, such as a servo motor, to rotate the grinder around a central axis; and a second actuator, such as a second servo motor or Z-axis ball screw, to press the substrate holder A CMP polishing layer or pad.

19. The device of the invention as described in any one of items 1 to 18 above, wherein the entire device is enclosed inside an airtight enclosure, such as where the relative humidity (RH) range can be 5 to 100% (e.g. 5 To 50%).

Unless stated otherwise, temperature and pressure conditions are ambient temperature and standard pressure. All the ranges mentioned are inclusive and combinable.

Unless otherwise stated, any term containing parentheses may alternatively refer to the complete term (as if parentheses are absent and the term is without them) and the combination of each alternative. Accordingly, the term "(poly) isocyanate" refers to an isocyanate, a polyisocyanate, or a mixture thereof.

The entire range is inclusive and combinable. By way of example, the term "range 50 to 3000 cps, or 100 cps or greater" will include each of 50 to 100 cps, 50 to 3000 cps, and 100 to 3000 cps.

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

As used herein, the term "thickness change" means a value determined based on the largest change in the thickness of the CMP 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 platen platen and terminating at the outer periphery of the platen platen 178 ° to 182 °, or preferably 179 ° to 181 °, wherein the first and second line segments are in a plane orthogonal to the flat platen, and the plane passes through the center point of the CMP polishing layer and the rotary type The position on the periphery of the abrasive surface of the grinder is the farthest point 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 height of a surface relative to the best fit plane at any given point on the top surface of a given CMP polishing layer, the best fit The plane represents a horizontal surface parallel to and on the top surface of a given CMP polishing layer. An 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 plate

2‧‧‧CMP polishing layer or pad

3‧‧‧ window

4‧‧‧Rotary Grinder Assembly / Rotor

5‧‧‧ porous abrasive material

6‧‧‧ substrate holder

7‧‧‧ wafer

Fig. 1 depicts a rotary grinder device according to the present invention and shows a flat platen platen and a CMP polishing layer containing a transparent window.

FIG. 2 depicts a CMP polishing layer processed by the device of the present invention. The surface of the CMP polishing layer has a uniform groove microtexture structure defined by intersecting arcs, wherein the radius of curvature of each arc is equal to or slightly larger than that of the CMP polishing layer. radius.

Figure 3 depicts a rotary grinder with a substrate holder and a polishing device adapted to planarize or polish a substrate, such as a semiconductor, and a polishing device according to the present invention.

According to the present invention, the polishing device improves the surface micro-textured structure of the CMP polishing layer (including the CMP polishing pad and the top surface of the polishing layer). The device produces a uniform surface microtextured structure, which is characterized in that the surface of the CMP polishing layer has a series of intersecting arcs with the same radius of curvature as the circle defined by the outer periphery of the grinding surface of the rotary grinder. ; And the surface roughness of the upper surface of the CMP polishing layer is 0.01 to 25 μm Sq. The inventors have found that the CMP polishing layer treated by the rotary grinder according to the present invention has good performance and requires little or no conditioning, that is, it is a pre-conditioned type. In addition, the micro-textured structure of the pad surface of the CMP polishing layer treated by the rotary grinder enhances substrate polishing. The device of the present invention helps to avoid irregularities in the shape of the pad due to cutting, which may cause surface defects in the chemical mechanical polishing pads, such as gouges, and drums that are softer than the rest of the CMP polishing layer. bubble. In addition, the device of the present invention helps to minimize the negative effects due to the deformation of the polishing layer during pad stacking, in which two or more pad layers are passed through a nip group separated by a fixed distance. This is especially important for soft and compressible CMP polishing layers. In addition, the device and the treated pad of the present invention provide an optimized surface micro-textured structure, which reduces defects and improves uniform removal of material on the entire substrate surface (such as a semiconductor or wafer surface).

The inventors have found that grinding a CMP polishing layer with a porous abrasive material can complete the polishing without fouling the polishing medium and without damaging the substrate of the CMP polishing layer. The pores in the porous abrasive material are large enough to store particles removed from the CMP polishing layer substrate; and the porosity of the porous abrasive material is sufficient to store the body of the material removed during grinding. Preferably, blowing compressed air across the interface between the porous abrasive material and the substrate of the CMP polishing layer further helps to remove the abrasive substance and prevent the fouling of the polishing equipment.

In any method using the device of the invention, compressed gas or air can also be blown before or after grinding.

The device of the present invention may include a rotary grinder and a platen platen. The rotary grinder is lowered onto the CMP polishing layer resting on the platen platen at a set rate or feed rate.

As shown in FIG. 1, the device of the present invention grinds the surface of a CMP polishing layer positioned on the surface of a platen platen ( 1 ), which is equipped with a vacuum orifice (not shown). Place the CMP polishing layer or pad ( 2 ) 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 platform platen ( 1 ) in FIG. 1 has a vacuum exhaust port (not shown) to hold the CMP polishing layer ( 2 ) in place. In Figure 1, the CMP polishing layer ( 2 ) has a window ( 3 ). The grinding mechanism of the present invention includes a rotary grinding machine (rotary wheel) 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 It is arranged in a plurality of sections extending around the lower surface of the periphery of the rotor ( 4 ). There is a small gap between the sections. In FIG. 1, the rotary grinder assembly ( 4 ) is positioned so that its peripheral edge is just above the center point of the CMP polishing layer ( 2 ) as needed. In addition, the rotary grinder assembly ( 4 ) has a desired size. So that its diameter is approximately equal to the radius of the CMP polishing layer ( 2 ).

The device of the present invention may preferably include a grinder / conditioner and a polishing device, wherein the CMP polishing pad is mounted on a platen platen and the rotary polishing machine assembly and the substrate holder are independently lowered onto the CMP polishing pad to Each of them forms an interface with the top of the CMP polishing layer. The substrate holder is mechanically connected to or mounted on a first actuator, such as a servo motor, to rotate the substrate holder about a central axis; and a second actuator, such as a second servo motor or Z-axis ball screw, so that The substrate holder is pressed against the CMP polishing pad.

As shown in FIG. 3, the device of the present invention polishes the substrate while grinding the surface of the CMP polishing layer positioned on the surface of the platen-type platen ( 1 ). Place the CMP polishing layer or pad ( 2 ) 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 platform platen ( 1 ) in FIG. 3 has a vacuum exhaust port (not shown) to hold the CMP polishing layer ( 2 ) in place. In Fig. 3, the CMP polishing layer ( 2 ) has a window ( 3 ). The grinding mechanism of the present invention includes a rotary grinding machine (rotary wheel) 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 It is arranged in a plurality of sections extending around the lower surface of the periphery of the rotor ( 4 ). In addition, a substrate holder ( 6 ) or a wafer carrier that is offset from the rotary grinder assembly ( 4 ) holds a 300mm wafer ( 7 ) on its lower surface.

The grinding and polishing device operates as follows: a substrate (such as a semiconductor wafer) is held on the lower surface of the substrate holder and pressed against a CMP polishing pad on the upper surface of the platen-type platen. The platform-type platen and the substrate holder rotate relative to each other, thereby enabling the lower surface of the substrate to achieve sliding contact with the polishing pad. At this time, a polishing liquid nozzle (not shown) supplies a polishing liquid, such as an aqueous silicon dioxide or abrasive oxide, carbide or nitride particle slurry, to the polishing pad. The lower surface of the substrate is polished by a combination of abrasive particles in a polishing solution and mechanical polishing of the surface of the CMP polishing layer.

The rotary grinder of the present invention includes a circular rotary grinder assembly or a rotor, and the grinder assembly or rotor is provided with a porous abrasive material at its peripheral edge, preferably in a zigzag shape or including around the peripheral edge of the rotary grinder. Porous abrasive material with discrete points or gaps. The lower surface of the porous abrasive material is the abrasive surface of a rotary grinder. The porous abrasive material may be in the form of a ring or ring segment that is mounted or attached to the lower surface of the rotary grinder assembly. The porous abrasive material may include a radial array of downwardly facing turning sections, typically 10 to 40 porous abrasive material sections with a gap therebetween; or a perforated ring made of porous abrasive material with periodic perforations therein. Gaps or perforations allow compressed gas or air to be blown into the interface between the surface of the CMP polishing layer and the surface of the porous abrasive material before, during, or after grinding to remove the abrasive material and clean the porous abrasive material. In addition, the notches or gaps in the porous abrasive material help to cool the surface of the porous abrasive material and the substrate of the CMP polishing layer during polishing.

The device of the present invention can be positioned to compensate for undesired contour wear of the CMP substrate, such as when the contour wear of the CMP process is inconsistent, such as too little or too much removal at the edge of the substrate. This in turn can extend pad life. In such a position, the grinding surface of the rotary grinder assembly can be adjusted such that it is substantially parallel, but not exactly parallel, to the top surface of the platen platen or CMP polishing layer. For example, the grinding surface of a rotary grinder can be adjusted to produce a center thickness (the angle between the radius of the rotary grinder and the platform platen exceeds 180 °, the plane where the angle lies is orthogonal to the platform platen and passes through The center point of the CMP polishing layer and the position on the peripheral edge of the grinding surface of the rotary grinder is the point farthest from the center point of the CMP polishing layer) or the center is thin (the angle is less than 180 °).

The device of the present invention can be used in a humid environment, such as combined water or ground aqueous slurry, such as silica or cerium dioxide slurry.

Since the size of the rotary grinder element can be changed, the device of the present invention can be scaled to fit CMP polishing layers of various sizes. According to the device of the present invention, the platform platen should be larger than the CMP polishing layer or preferably have a radius equal to the radius of the CMP polishing layer or a radius within 10 cm longer than the radius of the CMP polishing layer. The device can thus be scaled to process CMP polishing layers with a radius of 100mm to 610mm.

Various rotary grinder assemblies can be used with the device according to the invention, one at a time. The rotary grinder assembly is selected so that its diameter matches or is slightly larger than the radius of the CMP polishing layer being ground. Alternatively, the rotary grinder assembly is adapted to allow porous media of various diameters to grind a media ring or disc (preferably a single washer) to adhere to the lower surface of its periphery.

Various substrate holders can be used with the device according to the invention, one at a time. The substrate holder is selected so that its diameter is smaller than the radius of the CMP polishing layer used for polishing and larger than the diameter of the substrate being polished.

The device of the present invention can provide a CMP polishing layer or pad that does not exhibit window bulging and defects caused by cutting. Therefore, according to a method using the apparatus of the present invention, a CMP polishing layer can be formed by molding a polymer to form a porous molding having a desired diameter or radius, which diameter or radius will be the size of a pad made therefrom. , And then cutting the molded article to a desired thickness, which will be the target thickness of the pad manufactured according to the present invention, and then grinding the pad or CMP polishing layer to provide the desired pad surface on the pad polishing surface Micro-textured structure.

In the method using the apparatus of the present invention, a single layer or a single pad and a stacked pad having a sub-pad layer can be ground. Preferably, in the case of stacked pads, the method includes grinding the CMP polishing layer after the stacked pads, so that grinding can help eliminate deformation of the stacked pads.

A suitable CMP polishing pad can be formed by molding the polymer and cutting the polymer to form a CMP polishing layer for use as a pad, or preferably by forming the polymer and cutting the polymer to form a CMP polishing layer, and then The CMP polishing layer is stacked on top of a sub-pad or bottom layer having the same diameter as the CMP polishing layer to form a CMP polishing pad.

In a method using the apparatus of the present invention, it may include forming a CMP polishing pad, forming a groove in the pad (such as by turning the pad), and then grinding the CMP polishing pad with a rotary grinder to form a pad surface micro The texture structure includes a series of visible intersecting arcs on the polishing surface and the curvature radius is equal to or greater than (preferably equal to) the polishing layer radius, and the substrate is planarized with a CMP polishing pad. In such methods, the CMP polishing pad is conditioned and surface reconstituted during use.

In the method using the device of the present invention, it may include forming a CMP polishing pad, and grinding the CMP polishing pad with a rotary grinder to form a micro-textured structure on the surface of the pad, including polishing on a polishing surface with a curvature radius equal to or greater than (preferably) polishing. A series of visible intersecting arcs of the layer radius while planarizing the substrate with a CMP polishing pad, and then forming grooves in the pad, such as by turning the pad to form the groove.

In addition, the apparatus of the present invention can be used as a CMP polishing or planarizing tool, that is, a grinding and polishing apparatus.

In another aspect, the present invention provides a method using the grinding and polishing apparatus of the present invention. According to the method of using the grinding and polishing device of the present invention, a CMP polishing pad is attached to the upper surface of a platen-type platen and a substrate (such as a semiconductor wafer to be polished) is clamped to a substrate holder so that the substrate holder The lower surface can be lowered onto the CMP polishing pad located on the platen platen, and then all the platen platen, the rotary grinder assembly and the substrate holder are rotated.

In the method of using the grinding and polishing apparatus of the present invention, a polishing liquid containing abrasive particles such as silicon dioxide, cerium dioxide, or alumina or a mixture thereof is supplied to and retained on a polishing pad. During operation, the substrate holder applies a desired downward pressure of 2 to 69 kPa, preferably 3 to 48 kPa, to the platen platen, and therefore, while the substrate holder and platen platen rotate, they are held against the CMP polishing pad. The surface of the substrate is flattened.

Preferably, in the method for polishing a substrate according to the present invention, the substrate holder and the platform-type platen are rotated in the same direction.

A CMP polishing layer suitable for use in accordance with the method of use of the device of the present invention includes a polymer or preferably a porous polymer, a polymer foam, or a porous polymer material containing a filler, according to ASTM D2240-15 (2015) A Shore D hardness of 80 or, for example, 40 or less.

Preferably, the method of the present invention can be performed on any CMP polishing pad, including a CMP polishing pad made of a relatively soft polymer, and especially used to treat soft pads having a Shore D hardness of 40 or less.

The CMP polishing layer suitable for use according to the method of using the device of the present invention may further include one or more non-porous transparent window sections, such as window sections including non-porous polyurethane having a glass transition temperature (DSC) of 75 to 105 ° C. , Such as a window section that does not extend past the center point of the CMP polishing layer. In such a CMP polishing layer, one or more window sections have a top surface that varies with respect to the largest dimension of the window (such as the diameter of a circular window, or a rectangular window) according to a window thickness change of 50 μm or less. The greater of its length or width).

In addition, the CMP polishing layer suitable for use with the method of using the device of the present invention may include multiple pores or micro-elements with an average particle size of 10 to 60 μm, preferably polymer microspheres. Preferably, the CMP polishing layer has a higher-density and lower-density alternating endless belt extending outwardly from the center point of the CMP polishing layer to its outer periphery. For example, the density of higher density endless belts is 0.01 to 0.2 g / cm ³ higher than that of lower density endless belts.

Accordingly, a chemical mechanical (CMP) polishing pad made according to the method of using the device of the present invention includes a porous polymer CMP polishing layer having a radius, the CMP polishing layer having at least 0.01 μm to 25 μm Sq or preferably 1 μm to 15 μm Sq has a surface roughness and has a series of visible intersecting arcs on the surface of the polishing layer, the radius of curvature of the intersecting arcs being equal to or greater than (preferably) half the radius of curvature of the polishing layer. Preferably, the series of visible intersecting arcs extend around the center of the polishing layer and extend across the surface of the polishing layer in a radial symmetry.

The CMP polishing pad made according to the method of using the device of the present invention has a center point and a radius. Such polishing pads may have a thickness by which the pad is inclined such that the closer it is to its center point, the greater the thickness becomes, or the further it is inclined from the center point, the greater the thickness becomes.

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

Example 1: Two forms of a 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 hardness of the polyurethane is It is 64.9. In Example 1-2, the CMP polishing layer includes stacking the same polyurethane pad of Example 1-1 onto a SUBA IV ^TM particle made of polyester felt (Dow) using a pressure-sensitive adhesive. Mat to get a stack of mats.

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

All pads have 1010 grooves (concentric circle groove pattern with 0.0768cm (0.030 ") depth x 0.0511cm (0.020") width x 0.307cm (0.120 ") pitch) and no window.

The porous abrasive material was a vitrified porous diamond abrasive having an average abrasive size of 151 μm. To grind the substrate, the rotary grinder assembly is positioned parallel to the top of the platen platen and rotates counterclockwise at 284 rpm and the platen aluminum platen rotates clockwise at 8 rpm. Starting from the point where the porous abrasive material just touched the substrate of the CMP polishing layer, the rotary grinder assembly was fed down to the platen platen at a rate of 5.8 μm (0.0002 ") increments per 3 pad revolutions. During this period The compressed dry air (CDA) is 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 is located just above the center point of the CMP polishing layer and the other is behind the porous abrasive material. The side is about 210mm (8.25 ") from the center of the pad. Grinding lasted about 5 minutes.

The pad removal rate, non-uniformity, and chatter marks (defectivity) from Example 1 were evaluated in a polishing test as follows:

Removal rate: On a 200mm-sized tetraethoxysilicate (TEOS) substrate, the substrate was flattened by using a specified pad and a 200ml / min flow rate of ILD3225 ^TM smoke-like silica aqueous slurry (Dow). Determination. Using a Mirra ^TM polishing tool (Applied Materials, Santa Clara, CA), at a 93/87 platen / substrate carrier, the polishing pressure was 0.11, 0.21, and 0.32 kg / cm ² (1.5 , 3.0, 4.5 psi) down pressure. Before testing, use SAESOL ^TM 8031C1 disc (sintered diamond dust surface, 10.16 cm diameter, Saesol Diamond Ind. Co., Ltd., Korea) ) As a conditioner, all polishing pads were conditioned for 40 minutes at 3.2 kg (7 pounds). During the test, the same conditioning was continued on the pads. Each pad was tested for a total of 18 wafers and averaged.

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

Flutter or defect count: The same TEOS substrate that was flattened 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 obtained pad has a pad surface micro-textured structure including an intersecting arc line having a radius of curvature equal to a radius of curvature of a peripheral edge of the rotary grinder assembly. In addition, as shown in Table 1 below, the flattening rate generated by the pads of Examples 1-1 and 1-2 of the present invention on the substrate is the same 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 which have not been subjected to the polishing method of the present invention, the pads of Examples 1-1 and 1-2 of the present invention have significantly reduced defects and significantly reduced chatter marks in the substrate.

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

Tests were performed on 14 pads and the average results of thickness changes were reported, which were 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 pad center to the edge. The thickness change is calculated by subtracting the thinnest measurement from the thickest measurement. The results are shown in Table 2 below.

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

Example 3: The surface roughness of the pad of Example 2 was measured compared to a commercially available IC1000 ^™ pad (Dow). The pad of Comparative Example 2 was the same pad of 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 pad center to the edge 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 structure and a defined surface roughness characterized by a reduced valley depth.

Claims (11)

    A device for providing a pre-conditioned polymer chemical mechanical (CMP) polishing pad or layer with a micro-textured structure on a pad surface and a polishing substrate, the device comprising: a rotary grinder assembly having a wheel or a rotor; The wheel or rotor has a grinding surface of a porous abrasive material; a flat platen for holding the CMP polishing layer in place, the grinding surface of the rotary grinder is placed above the surface of the flat platen and parallel to Or substantially parallel to the surface of the platform-type platen to form an interface between the surface of the CMP polishing layer and the surface of the porous abrasive material; and a substrate holder, the substrate-holder being positioned on the platform-type Above the top surface of the platen and parallel to the top surface of the flat platen plate so as not to overlap the area where the rotary grinder assembly is placed and the area where the CMP substrate is attached, so that the A polishing interface is generated between the surface and the surface of the CMP polishing layer, wherein the substrate holder is independent of the rotary grinder assembly and the platform press. Rotate.         The device of the present invention as claimed in claim 1, wherein the flat platen holds the CMP polishing layer in place by vacuum.         The device of the present invention as claimed in claim 1, wherein said CMP polishing layer has a radius extending from its center point to its outer periphery and said grinding of said wheel or rotor of said rotary grinder assembly The surface has a diameter equal to or larger than the radius of the CMP polishing layer.         The device of the present invention as claimed in claim 3, wherein the diameter of the rotary grinder assembly is equal to the radius of the CMP polishing layer.         The device of the present invention as claimed in claim 1, wherein the wheel or rotor of the rotary grinder assembly is positioned so that during grinding, the outer peripheral edge of its grinding surface is directly placed on the CMP polishing On the center of the layer.         The device of the present invention as claimed in claim 1, wherein the rotor or rotor of the rotary grinder assembly, the CMP polishing layer, and the platen platen are each rotated during the polishing of the CMP polishing layer.         The device of the present invention as claimed in claim 1, wherein the rotary grinder assembly includes a drive housing including a motor or a rotary actuator, and is connected to and driven by the motor or the rotary actuator. Or rotary actuator driven vertical mounted axles that extend into the drive housing and are connected to the runner or rotor at its lower end by a mechanical linkage so that it is at the desired number of revolutions per minute (rpm) rotation.         For example, the device of the present invention in the scope of patent application, wherein in the drive housing, the vertically arranged wheel axle includes a ball screw or a secondary servo motor, and the ball screw or the secondary servo motor is located between the wheel shaft and the The connection of the motor or the rotary actuator, the mechanical connection of the wheel and the rotor or the rotor, or these two positions, whereby the rotor of the rotary grinder assembly can be made Or the rotor feeds down at the set increment rate.         The device of the invention as claimed in claim 1 further comprises a conduit, hose, nozzle or valve for intermittently or continuously blowing a compressed inert gas or air and positioned to blow said inert gas or air into the place In the interface of the surface of the CMP polishing layer material and the surface of the porous abrasive material to impact the porous abrasive material during grinding; and separately include a second conduit, hose, or valve for A compressed inert gas or air is blown upward from a point just below the peripheral edge of the rotary grinder assembly to impact the porous abrasive material during grinding.         According to the device of the present invention, the diameter of the substrate holder is smaller than the radius of the CMP polishing layer or pad held by the platform platen, and in addition, the substrate The holder is mechanically connected to or mounted to a first actuator to rotate the grinder around a central axis; and a second actuator to press the substrate holder against the CMP polishing layer or pad.         The device of the present invention as claimed in claim 1, wherein the entire device is enclosed inside an airtight enclosure.