KR200419311Y1 - Polishing pad conditioner with abrasive patterns and channels - Google Patents

Abstract

The polishing pad conditioner includes a base and a pad conditioning a front surface over the base. The conditioning face includes a central and peripheral region. An abrasive spoke having a substantially constant width of abrasive particles extends from the center to the peripheral region. The spokes are symmetrical and radially spaced apart from one another and can have various shapes. Also, when the conditioning face is rubbed against the polishing pad, the conditioning face is at the cutout inlet channel containing the polishing slurry, the conduit to receive the polishing slurry from the cutout inlet channel, and at the peripheral edge of the base to release the received polishing slurry. It may be provided with an outlet.

Description

POLISHING PAD CONDITIONER WITH SHAPED ABRASIVE PATTERNS AND CHANNELS}

1A (Prior Art) is a partial side view of a rough polishing pad with upright fibers.

FIG. 1B (Prior Art) shows the polishing pad of FIG. 1A after the pad has been used to entangle the fiber to smooth out and block with waste particulate;

2 (Prior Art) is a plan view of a pad conditioner assembly conditioning a conditioning arm and a polishing pad.

3A-3D (Prior Art) are substantially covered with abrasive particles (FIG. 3A) and have a peripheral ring of abrasive particles (FIG. 3B), divided into multiple radial arcs of abrasive particles (FIG. 3C). Perspective view of a pad conditioner with conditioning pads, divided into wedges of abrasive particles oriented tangentially along an inner circle (FIG. 3D).

4 is a perspective view of a pad conditioner with a conditioning surface comprising straight legs of abrasive particles in which abrasive spokes are radially spaced apart from one another.

5 is a perspective view of a pad conditioner with conditioning surfaces spaced apart by polishing arcs located at different radial distances.

FIG. 6 is a perspective view of a pad conditioner having a conditioning surface comprising an S-shaped leg of abrasive particles in which the abrasive spokes extend radially outwardly from an inner circle; FIG.

FIG. 7 is a perspective view of a pad conditioner with a surface in which the abrasive spokes comprise a straight leg of abrasive particles and a second abrasive particle of tetrahedron thereon;

8 is a perspective view of a pad conditioner with a conditioning face that includes an array of abrasive squares spaced apart from each other and located in a non-polishing grid.

9A is a perspective view of a pad conditioner on which a cutout inlet channel includes a conditioning face with a conduit for receiving a polishing slurry from the cutout channel and the outlet of the peripheral edge;

9B is a cross-sectional view of the pad conditioner of FIG. 9A showing a cutout inlet channel, conduit, and outlet of the pad conditioner.

FIG. 9C is an exploded perspective view of the pad conditioner of FIG. 9A overturned, showing a conditioning face with a cutout inlet channel, and a rear face with conduits and outlets. FIG.

10A is a perspective view of a CMP polishing machine.

10B is a partially exploded perspective view of the CMP polishing machine of FIG. 10A.

10C is a diagrammatic top view of the CMP polishing machine of FIG. 10B.

FIG. 11 is a diagrammatic top view of a substrate to be polished and a polishing pad conditioned by the CMP grinder of FIG. 10A. FIG.

FIG. 12 is a perspective view of a portion of the conditioning head assembly of the CMP grinder of FIG. 10A when the polishing pad is in conditioning. FIG.

※ Description of code for drawing code ※

20: polishing pad 50, 50a to 50c: pad conditioner

52: conditioning face 54, 54a, 54b: abrasive grain

58: base 70: abrasive spokes

74: center region 76: peripheral region

82a to 82d: arc shape 84, 84a to 84d: polishing arc

91: polished square 94: cutout inlet channel

95, 95a, 95b: conduit 96: outlet

97: peripheral edge 100: chemical mechanical polishing machine

108, 108a to 108c: polishing station 112: substrate transfer station

116: rotating carousel 120: rotating substrate holder

140: substrate 160: support plate

162: slot 172: shaft

176: motor 178: removable sidewall

182, 182a to 182c: rotating platen 184, 184a to 184c: polishing pad

188, 188a-188c: Conditioning Assembly 192: Table Top

196: conditioning head 200: arm

204: Base 208: Cup

220: water jet 224: polishing pad surface

Embodiments of the present invention relate to a pad conditioner for conditioning a chemical mechanical polishing pad.

Chemical mechanical polishing (CMP) is used in the manufacture of integrated circuits and displays to smooth the surface topography of the substrate for subsequent etching and deposition processes. A typical CMP apparatus includes a polishing head that vibrates and pressurizes a substrate against a polishing pad while abrasive grain slurry is supplied therebetween to polish the substrate. CMP can be used to form flat surfaces, polysilicon or silicon oxides, deep or shallow trenches filled with metal films, and other layers in dielectric layers. CMP polishing has generally been considered to occur as a result of chemical and mechanical influences, for example, chemically altered layers are repeatedly formed on the surface of the material being polished and removed. For example, in metal polishing, a metal oxide layer is formed and repeatedly formed and removed from the surface of the metal layer being polished.

During the CMP process, the polishing pad 20 is periodically conditioned by the pad conditioner 24. After polishing a plurality of substrates, as shown in FIGS. 1A and 1B, the polishing pads 20 are accumulated or trapped residues 28 that block the space 30 between the twisted fibers and the pads 20 fibers. This results in a smoother surface. The resulting smooth pad 20 results in no retaining polishing slurry and results in increased defects and in certain cases may also result in non-uniform polishing of the substrate. In order to improve the pad smoothing, the pad 20 is provided by a pad conditioner 24 having a conditioning face 32 with abrasive particles 34, such as diamond particles, as shown in FIG. 2. Conditioned periodically, the conditioning surface is pressed against the used polishing surface 38 of the polishing pad 20. The conditioner 24 rotates relative to the pad surface to condition the pads 20 to remove polishing debris, eliminate pore and fiber obstruction on the polishing surface 38, and sometimes also form fine scratches that retain the polishing slurry. The pad conditioner 24 is then mounted to an arm 36 oscillating back and forth as shown by the second position of the dotted arm 36a. The pad conditioning process can be performed during the polishing process-known as in-situ conditioning-or outside the wafer polishing process known as ex-situ conditioning.

Conventional pad conditioner 24 may be covered with a continuous layer of abrasive particles 34, or a pattern strip. For example, FIG. 3A shows a pad conditioner 24 in which abrasive particles cover the entire conditioning face 32. A circular strip 40 of abrasive particles along the periphery of the conditioning pad has also been used as shown in FIG. 3B. The circular strip 40 may be broken into segments 40a and 40b while the abrasive particles and smooth areas alternately form bands, as shown in FIG. 3C. In another configuration, the wedges 42 of the abrasive particles 24 are disposed spaced apart from one another and extend tangentially across the conditioning face 32 as shown in FIG. 3D. The abrasive particle pattern can be used to limit the amount of diamond bonded area that can limit the cost. However, some of these patterns often result in non-uniform and uneven pad conditioning that can vary across the pad surface. The patterned polishing pad configuration can also be a cause for the slurry to get stuck or trapped within a specific area of the pad conditioner 24, further reducing the uniformity of the pad conditioning.

Conventional pad conditioner 24 also picks up the polishing slurry from polishing pad surface 38 and results in dry slurry accumulation while splashing when randomly draining the slurry from the edge of pad conditioner 24. For example, as shown in FIG. 2, the centrifugal force generated by the rotating pad conditioner 24 causes the slurry picked up by the pad conditioner 24 to move the edge of the pad conditioner as shown by arrow 44. To squirt out. Depletion of the slurry from the surface of the polishing pad 20 by the pad conditioner 24 can cause dry spots on the polishing pad surface and can result in increased particle defect counts and very large / very small scratched defects.

Thus, it is desirable to have a pad conditioner with a conditioning face that provides uniform and repeatable conditioning of the polishing pad. It is also desirable to condition the polishing pad without excessive loss of polishing slurry during the conditioning process. It is further desirable to have a pad conditioner that dispenses abrasive particles that provide optimum conditioning while controlling the amount of abrasive particles used on the conditioning side.

In one aspect, the polishing pad conditioner according to the present invention includes a base and a pad conditioning face on the base. The conditioning face includes a central and peripheral region. An abrasive spoke having substantially constant width abrasive particles extends from the center to the peripheral region. The spokes are symmetrical and radially spaced from each other.

In another aspect, the conditioning face comprises a plurality of abrasive arcs spaced by non-polishing strips. The polishing arc comprises one or more first arc sets at a _first radial distance R ₁ from the center of the conditioning face and a second arc set from the center of the conditioning face. Polishing arcs may have different circumferential lengths.

In another aspect, the conditioning faces comprise an array of polished squares spaced apart from each other and located in a non-polishing grid. The array provides a uniformly distributed abrasive particle square across the conditioning face while alternating the non-polishing and polishing regions.

In yet another aspect, the pad conditioning face includes one or more cutout inlet channels to receive the polishing slurry when the conditioning face is rubbed against the polishing pad. The conduit receives the polishing slurry from the cutout inlet channel. An outlet at the peripheral edge of the base is provided to discharge the received polishing slurry. This embodiment allows recycling of the polishing slurry to preserve the slurry.

The features, features and advantages of the present invention are better understood by the following detailed description, the appended claims and the drawings which illustrate embodiments of the present invention. However, it is to be understood that each feature may be used in the present invention, not merely in relation to a particular drawing, but may be used in general and that the present invention may include any combination of such features.

The polishing pad conditioner 50 according to an embodiment of the present invention is a pad having abrasive particles 54 rubbed against the polishing pad to condition the pad during the chemical mechanical polishing process, as shown in FIGS. 4 to 8. And a conditioning face 52. Base 58 is a support structure that provides structural strength and may be made of steel, or other rigid material, such as acrylic or aluminum oxide. Generally, base 58 includes a flat circular body, such as a disk. The base 58 may also be formed by the conical widening of two threaded holes 62a, 62b, or base 58, through the conditioning face 52 such that a screw or bolt is inserted to hold the base 58 in the grinder. Like a locking socket (not shown) located in the center of the rear face 64, a mechanism for holding the pad conditioner 50 in the CMP grinder may be included. While the illustrated embodiment of the pad conditioner 50 is described herein, it is to be understood that other embodiments are also possible, such that the scope of the claims is not limited to such illustrated embodiment.

The conditioning face 52 may be the front surface of the base 58, or as a disk having a back face provided with abrasive particles 54 as the front face and the adhesive face 46, as shown in FIG. 8, It can be formed in a separate structure. The adhesive surface 46 is generally relatively smooth or slightly roughened into grooves (not shown) to prevent easy removal or loosening from the strong frictional forces generated when the pad conditioner 50 is pressed against the polishing pad during the CMP polishing process. It may be connected to the receiving surface 48 of the base 58 to form a firm bond. The adhesive face 46 may be secured to the receiving face 48 of the base 58 with a brazing alloy or an epoxy adhesive, such as a nickel alloy.

In one embodiment, the conditioning face 52 comprises a matrix material that supports and holds the abrasive particles 54. For example, the matrix material may be a metal alloy, such as a nickel or cobalt alloy, which is coated in a desired pattern on the conditioning face 52, resulting in the abrasive particles 54 being embedded into the thermosoft film. In another aspect, the abrasive material 54 is initially positioned at the front conditioning face 52 of the base 58 such that the alloying material is formed to form the conditioning face 52 forming a unitary structure with the base 58. Penetrates between abrasive particles 54 in high temperature, high pressure manufacturing processes. In another embodiment, as described, for example, in US Pat. No. 6,159,087, commonly assigned to Birang et al., Which is incorporated herein by reference in its entirety, the matrix also incorporates abrasive particles 54 to cover the XY plane of the grid. As a result, the mesh may be fixed at positions related to each other. The mesh may be a wire mesh, such as a nickel wire, or a polymer string mesh.

The abrasive particles 54 are selected as the material having a higher hardness value than the material hardness of the polishing pad or polishing slurry particles. Suitable hardness of the abrasive particles is at least about 6 Mohr and preferably at least 8 mowers. Commonly used abrasive particles 54 include industrially produced diamond crystals. For example, the conditioning face 52 includes up to about 60% or more of the diamond volume, or up to about 90% or more of the diamond volume, with the remainder of the support matrix surrounding the particles 54. Abrasive particles 54 are also hard phase boron, such as cubic or hexagonal structures, as known, for example, in US Pat. Nos. 3,743,489 and 3,767,371, both of which are incorporated herein by reference in their entirety. It can be a carbide decision.

Typically, abrasive particles 54 are selected by size, such stone size, or weight, to provide the desired level of roughness of conditioning face 52. The abrasive particles 54 are also aligned by particles 54 having a relatively sharp outline or crystal cleavage as compared to particles having a shape, ie a relatively smooth outline. For example, abrasive particles 54, filed on July 8, 2004, and fully incorporated herein by reference, and described in commonly assigned patent application 10 / 888,941, also exhibit substantially identical crystal symmetry about an axis or cross section. It may be chosen to have a crystal structure. The abrasive particles 54 may be selected such that at least about 80%, and preferably more, at least about 90% of the particles 54 have the same crystal symmetry. Each symmetric abrasive particle 54 may be individually positioned, for example a mesh that is oriented and symmetrical with the point of symmetry pointed in a particular direction, for example in a direction perpendicular to the plane of the conditioning face 52. Are not spaced apart). The conditioning face 52 of the pad conditioner 50 may also be formed by embedding or encapsulating abrasive particles 54, such as metallized symmetric diamond particles formed in selected areas of the base 58 surface. For example, a nickel encapsulant may be first mixed with the selected symmetric diamond particles and then applied only to the desired area of the front face of the base 58. Suitable metals are brazing alloys and other metals and alloys used as joining techniques, such as diffusion bonding, hot pressing, resistance welding, and the like. The brazing alloy includes a low melting point metal component, which reduces the melting point temperature of the metal alloy to a melting point temperature that is typically less than about 400 ° C. and below the melting point temperature of the base where the conditioning surfaces are bonded together. Suitable brazing alloys include nickel base alloys.

Embodiments of the present invention of the pad conditioner 50 are designed to provide uniform pad conditioning, constant pad wear rate, and optionally optimal bonding properties such as low consumption slurry. This is achieved by the uniquely designed polishing area of the conditioning face 52 of the pad 50. For example, in one aspect, the pad conditioner 50 has a leg of substantially constant width from the central region 74 to the peripheral region 76 of the conditioning surface 52, as shown in FIG. 4. And a conditioning face 52 having an abrasive spoke 70 having abrasive particles. The spokes 70 extend outwardly from the inner circle 78 on the conditioning surface 52 which is symmetrical, radially spaced from each other and free of abrasive particles. The non-abrasive region 80 between the abrasive spokes 70 and the spokes 70 is selected to be oriented from the inner circle 78 so that the spokes 70 intersect each other to block the slurry flow region or the non abrasive region 80. Prevent it. The spokes 70 may extend beyond the conditioning surface 52 and wrap upward around the sidewalls 81 of the base 58. Sidewall extensions 83 provide more uniform conditioning that extends completely to the edge of the conditioning pad.

In one embodiment, the spokes 70 may be straight legs 70a that are spaced apart and radially extend outwardly from the inner circle 78. For example, the central axis 79 of each straight leg spoke 70a is separated at an angle θ of 15 degrees to 45 degrees to provide about 6 to about 20 spokes over the entire 360 degree angle range of the conditioning surface. The straight leg spokes 70a are separated by a non-abrasive wedge region 80 that is smooth and free of abrasive particles. The abrasive particles of the straight leg spokes 70a and the non-abrasive wedges 80 are advantageous because they together channel the slurry flow outward.

In another embodiment, the spokes 70 are sinusoidally curved S-shaped legs that cross the surface of the conditioning face forming two or more arch shapes 82a, 82b, as in the embodiment shown in FIG. 70b). Adjacent sigmoidal legs 70b are disposed such that the arch shapes 82a, 82b and 82c, 82d each draw the same sigmoid across the conditioning surface 52. The sigmoidal leg 70b is advantageous because the distance that the slurry flows outward is increased to keep the slurry under conditioning process for a longer period of time. In another embodiment, the spoke 70 further includes a tetrahedron 70c forming a second polishing region appended to the polishing straight leg 70a. The spokes may have a first abrasive particle 54a and the tetrahedron 70c may have a second and different type of abrasive particle 54b, or it may be the same type of abrasive particle but different area density, size, or It can be formed from both forms.

In another aspect, the conditioning face, in the embodiment shown in FIG. 5, includes a plurality of abrasive arcs 84 of a given width and spaced apart from the non-abrasive arcuate strip 86. The polishing arc 84 is at least a first set of arcs 84a at a first radial distance R ₁ from the center 85 of the conditioning face, and from the center 85 of the conditioning face 52 and the conditioning face 52. A second set of arcs 84b at a second radial distance R ₂ closer to the end 87. The distance R ₁ may be between about 6.35 mm (0.25 ″) to about 25.4 mm (1 ″) and the distance of R ₂ may be between about 50.8 mm (2 ″) and about 101.6 mm (4 ″). Preferably, the conditioning surfaces 52 are only more than two sets of arcs, for example a series of abrasive arcs 84a to 84d each at a different radius from the center 85 of the conditioning surface 52 as shown. ) May comprise a set. For example, arc 84 can be separated by ΔR of 0.125R, where R is the radius of the conditioning face. Therefore, for the conditioning face 52 having a radius R of about 44.45 mm (1.75 ") to about 57.15 mm (2.25"), a suitable ΔR is about 3.175 mm (0.125 ") to about 12.7 mm (0.5"). In one embodiment, the conditioning face 52 with a radius of 25.15 mm (2.25 mm) may have nine polishing arcs 84 across the radial distance from the center to the boundary of the conditioning face 52.

Each polishing arc 84 also has a different circumferential length, meaning the length of the outer circumference of the polishing arc 84. The inner circumference of arc 84 is a function of the radius of the outer circumference. For example in FIG. 5, the center 85 of the conditioning face 52 has a polishing circle 88, which is a polishing arc having a circumferential length that gradually increases in size from the center of the conditioning face 52 to a radial distance ( 84a to 84d). Increasing arc size is advantageous because increasing distance from the center produces higher centrifugal force, which in turn causes a greater amount of slurry to concentrate in the outer region, thereby increasing the arc size, thereby creating a larger barrier. Provided to hold the slurry below the conditioning surface, which provides better conditioning of the polishing pad.

In another aspect, the conditioning face 52 includes an array of abrasive polygons 90 spaced from each other and positioned in the non-polishing grid 92. Grid 92 has intersecting lines 93 of non-abrasive material forming abrasive polygon 90. For example, the polygons 90 may be rectangular with sides having a regular structure of four or more sides, such as right angles, parallelograms of parallel planes, or hexagons. In one embodiment, the non-abrasive intersecting lines 93 of the grid 92, free of abrasive material, are separately equivalent to both X and Y planes defining a rectangular grid with square spaces between the non-polishing nets. Are spaced apart. Each abrasive rectangle 91 is covered with abrasive particles 54 to form an array of abrasive rectangles 91 spaced apart from each other and located in a non-polishing grid. For example, each rectangle 91 may be made from about 2.54 mm (0.1 ") to about 25.4 mm (1") for a conditioning surface having a surface area of about 54.516 mm ² (0.1 sq "; inch ² ). .

The aforementioned aspect of the pad conditioner 50 provides a patterned polishing area tailored to the shape and size that optimizes the conditioning of the polishing pad to provide more uniform cleaning and conditioning to the polishing pad. The patterned abrasive zones are interspersed with non-abrasive zones, synergistic bonds and optimized forms that provide better pad conditioning. In the above-described aspect, the pad conditioner 50 positions the polishing area symmetrically in a predetermined periodic interval arrangement that provides more uniform and uniform wear of the polishing pad. When the conditioning surface 52 is pressed across the surface of the polishing pad, the pad wears in multiple directions to provide better and more uniform conditioning of the polishing pad. In addition, the patterned area is chosen to be consistent in shape and size with less likelihood of variation in the polishing area from one conditioning pad to another.

In another aspect, the pad conditioner 50 is the other side 52, such as the conditioning pad face 52 of the design described above, or, for example, the conditioning face 52 having abrasive particles 54 of a continuously covered surface. And a slurry slurry recycling system that can be used in combination. In the embodiment shown in FIGS. 9A-9C, the pad conditioner 50 of this aspect includes one or more cutout inlet channels 94 that receive a polishing slurry when the conditioning surface 52 is rubbed against the polishing pad 20. ). The cutout inlet channel 94 is contoured to effectively recover the polishing slurry from the surface of the polishing pad 20. For example, in the illustrated embodiment, the cutout inlet channel 94 has a tapered inner section 94a and a peripheral region of the base 58 having a first width around the central region 74 of the base 58. It is contoured to an outer section 94b having a second width around 76. The larger width of the outer section 94b of the channel 94 picks up a larger amount of polishing slurry, such that the polishing slurry is directed towards the center inlet 102 and the narrower inner section 94a The velocity of the slurry as it is forced into the center inlet 102 is increased. As shown, in one aspect, the inner section 94a of the cutout inlet channel 94 spirals radially outward from the curved and tapered distal end 98 to an intermediate section 94c having a constant width parallel wall. The parallel walls are then flared in order to form the outer portion 94b of the channel 94 with a width of which the v-shaped ends 99 increase radially. The cutout inlet channel 94 may be a single channel, two channels (shown) or multiple channels.

One or more conduits 95 are provided in the base 58 to receive the polishing slurry from the cutout inlet channel 94. Conduit 95 extends through base 58 to form a network passage 101 through base 58. For example, in one aspect, the conduit 95 includes a plurality of passages 101 that radially spread radially from the central circular hole 102 in the central region 74 of the base. The central circular hole 102 receives the polishing slurry from the cutout inlet channel 94 which is distributed in the star passage 101. The passage 101 supplies one or more outlets 96 at the peripheral edge 97 of the base 58 to discharge the received polishing slurry. The outlet 96 is located at the peripheral edge 97 of the base 58 so that the polishing slurry is recycled to the peripheral edge 97 of the conditioning pad. This causes the polishing slurry to be released from the peripheral edge 97 of the pad conditioner 50 and returned to the surface of the underlying polishing pad where it is conditioned. As shown in FIG. 9B, conduits 95a and 95b extend radially outward from the opposite end of base 58 from center hole 102.

The pad conditioner 50 described above can be used with any type of CMP grinder, so that the above-described CMP grinder described the use of the pad conditioner 50 is not limited in scope of the present invention in use. One embodiment of a chemical mechanical polishing (CMP) machine 100 that may utilize a pad conditioner is shown in FIGS. 10A-10C. Generally, the grinder 100 includes a housing 104 comprising multiple polishing stations 108a-108c, a substrate transfer station 112, and a rotatable carousel 116 that operates an independently rotatable substrate holder 120. ). The substrate loading device 124 includes a tub 126 attached to a housing 104 that includes a liquid bath 132 containing a cassette 136 that includes a substrate 140. For example, tub 126 may comprise a cleaning solution or may be a megasonic rinse washer using ultrasonic waves to clean substrate 140 before or after polishing, or an air or liquid dryer. Arm 144 runs along linear track 148 and supports w ΔRist assembly 152, which is a cassette claw that conveys cassette 136 from holding station 155 into tub 126. 154 and substrate blade 156 for transferring the substrate from tub 126 to delivery station 112.

The carousel 116 has a support plate 160 with a slot 162 on which the shaft 172 of the substrate holder 120 extends, as shown in FIGS. 10A and 10B. The substrate holder 120 rotates independently and vibrates back and forth in the slot to obtain a uniformly polished substrate surface. The substrate holder 120 is rotated by each motor 176 that normally hides behind the removable sidewall of the carousel 116. In operation, the substrate 140 is loaded from the tub 126 into the delivery station 112, from which the substrate is initially delivered to the substrate holder 120, which is maintained in vacuum. The carousel 116 then transfers the substrate through a series of one or more polishing stations 108a-108c and eventually returns the polished substrate to the delivery station 112.

Each polishing station 108a-108c includes rotatable platens 182a-182c, as shown in FIG. 10B, which supports the polishing pads 184a-184c, the pad conditioner assemblies 188a-188c. do. Both the platens 182a-182c and the pad conditioner assemblies 188a-188c are mounted to the tabletop 192 inside the grinder 100. During the polishing process, the substrate holder 120 holds, rotates, and presses the substrate 140 against the polishing pads 184a to 184c attached to the rotating polishing platen 182, and the polishing platen is attached to the substrate ( A retaining ring is also provided surrounding the platen 182 to prevent slipping during the polishing process of the substrate 140 to retain the 140. As the substrate 140 and polishing pads 184a through 184c rotate about each, a measurable amount of the deionized polishing slurry, including, for example, colloidal silica or alumina, is supplied according to the selected slurry recipe. Both the platen 182 and the substrate holder 120 may be programmed to rotate at different rotational speeds and directions depending on the process recipe.

Each polishing pad 184 typically has multiple layers made of a polymer, such as polyurethane, and includes fillers for added steric stability, and an outer resilient layer. The polishing pad 184 may be worn and replaced after about 12 hours of use under typical polishing conditioning. The polishing pad 184 may be a rigid, incompressible pad used for oxide polishing, a flexible pad used in other polishing processes, or a stacked pad. The polishing pad 184 has surface grooves that facilitate dispensing the slurry solution and trap the particles. The polishing pad 184 typically has a size at least several times larger than the diameter of the substrate 140, and the substrate remains off center on the polishing pad 184 to prevent polishing onto the non-flat surface over the substrate 140. do. The substrate 140 and the polishing pad 184 may be rotated at the same time on the axis of rotation parallel to each other, but are not collinear to prevent tapered polishing into the substrate. Typical substrate 140 includes a display for a semiconductor wafer or electronic flat panel.

Each pad conditioning assembly 188 of the CMP apparatus 100 includes a conditioning head 196, an arm 200, and a base 204, as shown in FIGS. 11 and 12. The pad conditioner 50 is mounted on the conditioning head 196. The arm 200 includes a distal end 198a connected to the conditioning head 196 and a proximal 198b connected to the base 204, wherein the arm has a conditioner head 196 attached to a polishing pad surface ( Sweeping across 224, the conditioning surface 52 of the pad conditioner 50 conditions the polishing surface 224 of the polishing pad 184 by rubbing the polishing pad surface to remove impurities and regenerate the surface. do. Each polishing station 108 also includes a cup 208, which includes a wash liquid for rinsing or cleaning the pad conditioner 50 mounted to the conditioning head 196.

During the polishing process, the polishing pad 184 polishes the substrate mounted to the substrate holder 120, while the polishing pad 184 can be conditioned by the polishing conditioning assembly 188. The pad conditioner 50 has an abrasive disk 24 having a conditioning face 52 with abrasive particles 52 used to condition the polishing pad 184. Generally, the conditioning surface 52 of the disk 24 is pressed against the polishing pad 184 while rotating or moving the pad or disk along a vibrating or translating path. The conditioning head 196 sweeps the pad conditioner 50 across the polishing pad 184 in a reciprocating motion synchronized with the movement of the substrate holder 120 across the polishing pad 184. For example, the substrate holder 120 along with the substrate to be polished can be positioned at the center of the polishing pad and the conditioning head 196 with the pad conditioner 50 is immersed in the wash liquid contained within the cup 208. During the polishing process, the cup 208 is pivoted out of the way as shown by the arrow 212, and the pad conditioner 50 of the conditioner head 196 and the substrate holder 120 carrying the substrate are each It may be swept back and forth across the polishing pad 184 as shown by arrows 214 and 216. Three water jets 220 manage the water flow toward the slowly rotating polishing pad 184 to rinse the slurry from the polishing pad or top pad surface 224 while the substrate 120 is transferred back. Typical operation and general features of the polishing machine 100 are better described by US Pat. No. 6,200,199B1, filed March 31, 1998 by Gurusamy et al., Which is incorporated herein by reference and commonly assigned.

Referring to FIG. 12, the conditioner 196 operates and drive mechanism 228 to rotate the conditioner head 196 carrying the pad conditioner 50 about a longitudinal axis 254 oriented perpendicular to the center of the head. It includes. The actuation and drive mechanisms include a conditioning head 196 between an elevated contracted position and a lowered extended position (shown) where the conditioning surface 52 of the pad conditioner 50 engages the polishing surface 224 of the pad 184 and It further provides movement of the pad conditioner 50. The actuation and drive mechanism 228 includes a vertically elongated shaft 240 that can be formed from heat treated 440C stainless steel, which is finished with an aluminum pulley 250. Pulley 250 is a sturdy carrier with a belt 258 extending along the length of arm 200 and connected to a remote motor (not shown) that rotates shaft 240 about longitudinal axis 254. The stainless steel collar with upper and lower pieces 260 and 262 are coaxial with the drive axis 240, respectively. The shaft, pulley, and collar form a rigid structure that generally rotates in units about the longitudinal axis 254. A generally annular drive sleeve 266 of stainless steel connects the conditioning head 196 to the drive shaft 240 and applies hydraulic or pneumatic pressure to the pad conditioner holder 274. Drive shaft 240 transmits torque and rotation from pulley to sleeve 266 and a bearing is located between them (not shown).

An optional removable pad conditioner holder 274 may be located between the pad conditioner 50 and the backing plate 270, as shown in FIG. 12. Four conventional flat sheet-like spokes 282 with distal ends fixed to the annular rim 284 extend radially outward from the hub 278. The spokes 282 are elastically flexible upwards and downwards, allowing the rim to tilt relative to the axis 254 from the other neutral horizontal direction, while the spokes are substantially relative to the axis 254. Transversely inflexible, it effectively transfers torque and rotation about axis 254 from hub 278 to rim 284. Under the spokes, the backing plate comprises a rigid, generally disc-shaped polystyrene perephthalate (PET) plate 270 extending radially outward. The pad conditioner 50 may be mounted to the pad conditioning holder 274 by a cylinder magnet located in a matching cylinder hole of the screw or holder 274.

In operation, the conditioner head 196 is positioned above the polishing pad 20 described above, and the drive shaft 240 rotates to cause rotation of the pad conditioner 50. The conditioner head 196 is then shifted from the retracted position to the extended position to engage the conditioning surface 52 of the pad conditioner 50 with the polishing surface 224 of the polishing pad 184. For example, the descending force that condenses the pad conditioner 50 relative to the pad 184 can be controlled by modularizing the hydraulic or air pressure applied within the cylinder 266. The descending force is transmitted to the pad conditioner holder 274 through the drive sleeve 266, the hub 278, the backing plate 270, and then to the pad conditioner 50. The torque for rotating the pad conditioner 50 relative to the polishing pad 184 is from the drive shaft 240 to the hub 278, the spoke 282, the rim 284 of the backing plate 270, the pad conditioner holder 274. It is supplied to the pad conditioner 50 via. The bottom surface of the rotating pad conditioner 50 engages with the polishing surface of the rotating polishing pad 184 and reciprocates in the path along the rotating polishing pad as described above. During this process, the conditioning surface 52 of the pad conditioner 50 is dipped into a thin layer of polishing slurry on top of the polishing pad 184.

To clean the pad conditioner 50, the conditioner head is rinsed and the pad conditioner 50 is released from the polishing pad. The cup 208 is then pivoted at a position below the head so that the head 196 is extended to immerse the pad conditioner 50 in the wash liquid of the conditioner cup 208. The pad conditioner 50 is rotated about the axis 254 within the body of the wash liquid (rotation does not need to be changed because the pad conditioner is engaged with the pad). Rotation causes a flow of the cleaning liquid past the pad conditioner 50 to clean impurities from the pad conditioner, including the worn material from the by-products of the pad, polishing, and the like.

The above described aspect of the pad conditioner 50 uniformly roughens the polishing surface 224 of the polishing pad 184 as the surface 224 gradually becomes smooth from repeated polishing. The pad conditioner 50 also keeps the surface 224 of the pad 184 flat when the pattern of sweeping and head pressure causes uneven wear of the polishing pad 184. Surface 224 is maintained smooth by grinding under very uneven areas of pad 184. The symmetric abrasive particles 54 of the pad conditioner 50 provide a more consistent polishing rate due to the more uniform shape and symmetry of the abrasive particles 54 to provide uniformity of conditioning across the polishing surface 224 of the pad. Improve. The pad conditioner 50 is also more consistent and reproducible from one pad conditioner 50 to another because a pad conditioner with the same form of abrasive particles 54 produces a better and more uniform conditioning ratio. It provides a possible outcome.

Although the present invention has been described with reference to certain preferred embodiments, other embodiments are possible. For example, pad conditioners may be used in conventional techniques, for example in other types of applications that are apparently as sand surfaces. Other configurations of CMP polishers can also be used. Moreover, polishing patterns equivalent to the selective channel configuration or those described may also be used in accordance with one of the common techniques and parameters of the instrument explicitly described. Therefore, the spirit of the appended claims is not limited to the details of the preferred embodiments contained herein.

The present invention has a pad conditioner with a conditioning face that provides uniform and repeatable conditioning of the polishing pad, thereby conditioning the polishing pad without undue loss of polishing slurry during the conditioning process, and controlling the amount of abrasive particles used on the conditioning face. It is effective to have a pad conditioner that dispenses abrasive particles while providing optimum conditioning.

Claims (10)

(a) a conditioning face, the conditioning face including one or more cutout inlet channels for receiving a polishing slurry when the conditioning face is rubbed against a polishing pad; (b) one or more conduits for receiving said polishing slurry from said cutout inlet channel; And (c) one or more outlets at the peripheral edge of the base to release the received polishing slurry, Polishing pad conditioner. The method of claim 1, The cutout inlet channel includes one or more of the following characteristics, The above characteristics (1) said cutout inlet channel is tapered from a first width in a central region of said conditioning face to a second width in a peripheral region of said conditioning face, said second width being greater than said first width; (2) at least a portion of the cutout inlet channel is radially spiraled outward from the center to a peripheral region of the base; (3) the cutout inlet channel comprises a v-shaped end having a radially increasing width; (4) the cutout inlet channel includes a curved tapered inlet; (5) said cutout inlet channel comprising a middle section having a radially constant width, Polishing pad conditioner. The method of claim 1, The conditioning surface comprises a plurality of abrasive spokes comprising a central and peripheral region and a substantially constant width of abrasive particles extending from the central region to the peripheral region, Each of the abrasive spokes comprises a central axis and radially spaced apart from one another such that the central axis of adjacent spokes is separated by an angle of about 15 ° to about 45 °; Polishing pad conditioner. The method of claim 1, The conditioning surface comprises abrasive particles, At least about 80% of the abrasive particles have crystal structures that are substantially the same crystal symmetry, Polishing pad conditioner. A chemical mechanical device comprising the pad conditioner of claim 1; (Iii) a polishing comprising a platen for holding a polishing pad, a support for holding a substrate to the polishing pad, a drive for supplying power to the platen or the support, and a slurry distributor for dispensing slurry on the polishing pad. station; (Ii) a conditioner head for receiving the pad conditioner of claim 1; And (Iii) a drive for powering the conditioner head such that the conditioning surface of the pad conditioner can be rubbed against the polishing pad to condition the pad, Chemical mechanical devices. (a) a conditioning face, the conditioning face comprising at least one cutout inlet channel for receiving a polishing slurry when the conditioning face is rubbed against a polishing pad, the cutout inlet channel comprising an intermediate section having a constant radial width; Conditioning cotton; (b) one or more conduits for receiving said polishing slurry from said cutout inlet channel; And (c) one or more outlets at the peripheral edge of the base to release the received polishing slurry, Polishing pad conditioner. The method of claim 6, The cutout inlet channel includes one or more of the following characteristics, The above characteristics (1) said cutout inlet channel is tapered from a first width in a central region of said conditioning face to a second width in a peripheral region of said conditioning face, said second width being greater than said first width; (2) at least a portion of the cutout inlet channel is radially spiraled outward from the center to a peripheral region of the base; (3) the cutout inlet channel comprises a v-shaped end having a radially increasing width; And (4) the cutout inlet channel comprises a curved tapered inlet, Polishing pad conditioner. The method of claim 6, The conditioning surface comprises a plurality of abrasive spokes comprising a central and peripheral region and a substantially constant width of abrasive particles extending from the central region to the peripheral region, Each of the abrasive spokes comprises a central axis and radially spaced apart from one another such that the central axis of adjacent spokes is separated by an angle of about 15 ° to about 45 °; Polishing pad conditioner. The method of claim 6, The conditioning surface comprises abrasive particles, At least about 80% of the abrasive particles have crystal structures that are substantially the same crystal symmetry, Polishing pad conditioner. A chemical mechanical device comprising the pad conditioner of claim 6; (Iii) a polishing comprising a platen for holding a polishing pad, a support for holding a substrate to the polishing pad, a drive for supplying power to the platen or the support, and a slurry distributor for dispensing slurry on the polishing pad. station; (Ii) a conditioner head for receiving the pad conditioner of claim 6; And (Iii) a drive for powering the conditioner head such that the conditioning surface of the pad conditioner can be rubbed against the polishing pad to condition the pad, Chemical mechanical devices.

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