Grinding fluid distribution device and chemical mechanical grinding device

Abstract

The invention provides a grinding fluid distribution device and a chemical mechanical grinding device.The grinding fluid distribution device comprises a hollow cylinder and a coating roll shaft, an opening is formed in the hollow cylinder, the interior of the hollow cylinder is communicated with the outside through the opening, and the hollow cylinder is used for storing grinding fluid; the coating roll shaft is arranged at the opening and can move towards or away from the opening so as to block the opening or form a gap with the opening. The coating roll shaft is arranged at the opening of the hollow cylinder to control the outflow of the grinding fluid in the hollow cylinder, so that the grinding fluid can be uniformly provided.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor integrated circuits, and particularly to a slurry dispensing device and a chemical mechanical polishing device. Background Art

[0002] In the production process of semiconductors, it is often necessary to polish wafers using a chemical mechanical polishing device. A chemical mechanical polishing device generally includes a polishing head (head), a polishing pad (pad), a polishing pad conditioner (disk), a slurry dispensing arm (slurry arm), and a polishing platen for placing the polishing pad.

[0003] The chemical mechanical polishing device uses the polishing head to control the wafer to rub back and forth on the surface of the polishing pad. At the same time, the slurry provided by the slurry dispensing arm reacts with the surface of the wafer. Under the combined action of mechanical friction and chemical reaction, a part of the thin film on the surface of the wafer is removed. However, uneven distribution of the slurry, abrasive by-products generated during the polishing process, impurities such as slurry crystallization, etc. will reduce the surface roughness of the polishing pad and affect the polishing efficiency. Summary of the Invention

[0004] The purpose of the present invention is to provide a slurry dispensing device and a chemical mechanical polishing device, which can provide slurry evenly and ensure a stable polishing rate.

[0005] To solve the above technical problems, the present invention provides a slurry dispensing device for providing slurry, including: a hollow cylinder and a coating roller. An opening is provided on the hollow cylinder, and the inside of the hollow cylinder is communicated with the outside through the opening. The hollow cylinder is used for storing slurry; the coating roller is arranged at the opening and can move towards or away from the opening to block the opening or form a gap with the opening.

[0006] Optionally, as the coating roller moves towards the opening, the gap gradually decreases; as the coating roller moves away from the opening, the gap gradually increases.

[0007] Optionally, both ends of the coating roller have protrusions, and both ends of the inner side of the hollow cylinder have limiting devices. The protrusions are movably connected to the limiting devices, and the limiting devices are used to limit the range of movement of the protrusions towards or away from the opening.

[0008] Optionally, the limiting device includes a chute, and at least part of the protrusion is located in the chute.

[0009] Optionally, the coating roller can rotate around its axis.

[0010] Optionally, the caliber of the opening gradually increases along the extension direction of the coating roller.

[0011] Optionally, the abrasive liquid dispensing device further includes an abrasive liquid pipeline, which is communicated with the inside of the hollow cylinder to supply abrasive liquid to the inside of the hollow cylinder.

[0012] Optionally, a plurality of nozzles are respectively arranged on the hollow cylinders on both sides of the coating roller shaft for supplying cleaning liquid, and the orientation of the nozzles is adjustable.

[0013] Optionally, a cleaning liquid pipeline is arranged inside the hollow cylinder, and the cleaning liquid pipeline is communicated with a plurality of the nozzles to supply the cleaning liquid to the nozzles.

[0014] Optionally, the hollow cylinder is in the shape of a triangular prism, the coating roller shaft is arranged on one side edge of the triangular prism, and the nozzles are arranged on the adjacent two side surfaces of the triangular prism on both sides of the coating roller shaft.

[0015] Correspondingly, the present invention further provides a chemical mechanical polishing device, which includes the abrasive liquid dispensing device as described above. The chemical mechanical polishing device further includes a base, a lifting rod arranged on the base, and a polishing pad arranged below the abrasive liquid dispensing device. The lifting rod is connected to the abrasive liquid dispensing device and is used to drive the abrasive liquid dispensing device away from the polishing pad, or drive the abrasive liquid dispensing device close to the polishing pad so that the coating roller shaft contacts the polishing pad, so as to coat the abrasive liquid on the polishing pad.

[0016] In summary, in the abrasive liquid dispensing device provided by the present invention, it includes a hollow cylinder and a coating roller shaft. An opening is provided on the hollow cylinder, and the inside of the hollow cylinder is communicated with the outside through the opening. The hollow cylinder is used to store abrasive liquid; the coating roller shaft is arranged at the opening and can move towards or away from the opening to block the opening or form a gap with the opening. The present invention controls the outflow of the abrasive liquid in the hollow cylinder by arranging the coating roller shaft at the opening of the hollow cylinder, so as to be able to uniformly supply the abrasive liquid.

[0017] In the chemical mechanical polishing device provided by the present invention, the lifting rod is connected to the abrasive liquid dispensing device, drives the abrasive liquid dispensing device away from the polishing pad, or drives the abrasive liquid dispensing device close to the polishing pad so that the coating roller shaft contacts the polishing pad, so as to coat the abrasive liquid on the polishing pad. As the polishing pad and the abrasive liquid dispensing device rotate relative to each other, the abrasive liquid is uniformly coated on the polishing pad, so that the polishing rate of the wafer remains stable.

[0018] In addition, a number of nozzles are provided on the hollow cylinders on both sides of the coating roller shaft for supplying cleaning liquid. The orientation of the nozzles is adjustable, so that the cleaning liquid in the nozzles flushes the polishing pad at an inclined angle, thereby being able to flush out the impurities in the pores of the polishing pad, effectively cleaning the polishing pad and reducing the scratch defects caused by residual impurities. Description of the Drawings

[0019] Figure 1 is a schematic structural diagram of a chemical mechanical polishing device in the related art.

[0020] Figure 2 is a schematic structural diagram of a polishing liquid distribution device provided by an embodiment of the present invention.

[0021] Figure 3 is a partial cross-sectional schematic diagram of a polishing liquid distribution device provided by an embodiment of the present invention.

[0022] Figure 4 is a schematic diagram of a coating roller shaft coating polishing liquid provided by an embodiment of the present invention.

[0023] Figure 5 is a schematic diagram of a nozzle spraying cleaning liquid onto a polishing pad provided by an embodiment of the present invention.

[0024] Figure 6 is a schematic structural diagram of a chemical mechanical polishing device provided by an embodiment of the present invention.

[0025] Description of the Reference Numerals:

[0026] 1 - polishing head; 2 - polishing pad; 3 - polishing pad trimmer; 4 - polishing liquid distribution arm; 5 - polishing disk; 6 - wafer; 7 - polishing liquid distribution device; 71 - hollow cylinder; 711 - chute; 72 - coating roller shaft; 721 - protrusion; 73 - nozzle; 74 - cleaning liquid pipeline; 8 - base; 9 - lifting rod; 10 - polishing liquid. Detailed Embodiments

[0027] To make the objectives, advantages, and features of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and specific embodiments. It should be noted that the accompanying drawings are in very simplified forms and not drawn to scale, and are only used to conveniently and clearly assist in explaining the objectives of the embodiments of the present invention. In addition, the structures shown in the accompanying drawings are often part of the actual structures. In particular, the accompanying drawings need to show different emphases and sometimes use different scales.

[0028] As used in the present invention, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. As used in the present invention, the term "or" is generally used in the sense of including "and / or" unless the context clearly dictates otherwise. As used in the present invention, the term "several" is generally used in the sense of including "at least one" unless the context clearly dictates otherwise. As used in the present invention, the term "at least two" is generally used in the sense of including "two or more" unless the context clearly dictates otherwise. In addition, the terms "first", "second", "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", "third" may explicitly or implicitly include one or at least two of such features.

[0029] Figure 1 is a schematic structural diagram of a chemical mechanical polishing apparatus in the related art. Please refer to Figure 1 As shown, the chemical mechanical polishing apparatus mainly includes a polishing head 1, a polishing pad 2, a polishing pad conditioner 3, a polishing liquid dispensing arm 4, and a polishing platen 5 for placing the polishing pad 2.

[0030] During the chemical mechanical polishing process, the polishing head 1 controls the wafer 6 to rub back and forth on the surface of the polishing pad 2. At the same time, the polishing liquid provided by the polishing liquid dispensing arm 4 reacts chemically with the surface of the wafer 6, and a part of the thin film on the surface of the wafer 6 is removed under the combined action of mechanical friction and chemical reaction.

[0031] In this related art embodiment, the main functions of the polishing liquid dispensing arm 4 include supplying the polishing liquid. The polishing liquid is sent to the center of the polishing pad 2 through a single nozzle of the polishing liquid dispensing arm 4, and the polishing liquid is thrown off on the surface of the polishing pad 2 by the centrifugal force generated by the rotation of the platform, and a part of the thin film on the surface of the wafer 6 is removed through chemical reaction. However, the liquid flow supplied by a single nozzle is relatively narrow, and the polishing liquid is not easily dispersed quickly. In addition, the linear velocity at the edge of the polishing pad 2 is relatively large, and the polishing liquid at the edge is more easily thrown out, resulting in uneven distribution of the polishing liquid on the surface of the polishing pad 2 and affecting the polishing stability.

[0032] On the other hand, the method for cleaning impurities on the surface of the polishing pad 2 in this embodiment is as follows: The polishing pad conditioner 3 rubs back and forth on the surface of the polishing pad 2 to expose the impurities therein, and a row of nozzles below the polishing liquid dispensing arm 4 provides high-pressure flushing water to wash and remove the impurities. However, the row of nozzles below the polishing liquid dispensing arm 4 provides vertical flushing water, which will squeeze and block the impurities in the pores of the polishing pad 2 and cannot effectively clean the polishing pad 2. This not only affects the service life of the polishing pad 2, but also the residual impurities are likely to scratch the surface of the wafer 6.

[0033] To solve the above problems, Figure 2 is a schematic structural diagram of a polishing liquid dispensing device provided by an embodiment of the present invention. Please refer to Figure 2 As shown, the polishing liquid dispensing device provided in this embodiment is used to provide polishing liquid. The polishing liquid dispensing device 7 includes: a hollow cylinder 71 and a coating roller shaft 72. An opening is provided on the hollow cylinder 71. The inside of the hollow cylinder 71 is communicated with the outside through the opening. The hollow cylinder 71 is used to store the polishing liquid 10; the coating roller shaft 72 is arranged at the opening and can move towards or away from the opening, blocking the opening or forming a gap with the opening to control the outflow of the polishing liquid 10.

[0034] In this embodiment, the coating roller shaft 72 can move towards or away from the opening. When moving in the direction towards the opening, the gap with the opening can be reduced or the opening can be blocked. When moving in the direction away from the opening, the coating roller shaft can form a gap with the opening or increase the gap with the opening, thereby controlling the outflow of the polishing liquid 10. Specifically, the direction towards the opening refers to the direction pointing from the inside of the hollow cylinder 71 to the opening, and the direction away from the opening refers to the direction pointing from the opening to the inside of the hollow cylinder 71.

[0035] The present invention controls the outflow of the polishing liquid 10 in the hollow cylinder 71 by providing the coating roller shaft 72 at the opening of the hollow cylinder 71. Compared with the method of providing the polishing liquid through a single nozzle by the polishing liquid distribution arm in the related art, it can provide the polishing liquid more uniformly in the extending direction of the coating roller shaft.

[0036] In this embodiment, the axis line of the coating roller shaft 72 is located on the side where the opening faces the inside of the hollow cylinder 71. The polishing liquid 10 flows out from the gap formed between the coating roller shaft 72 and the opening. As the coating roller shaft 72 moves in the direction towards the opening (i.e., Figure 2 moving downward in Figure 2 ), the gap gradually decreases and finally blocks the opening. As the coating roller shaft 72 moves in the direction away from the opening (i.e.,

[0037] moving upward in ), the gap gradually increases. By changing or controlling the moving distance of the coating roller shaft 72 in the direction towards the opening, the width of the gap can be adjusted, and the outflow volume of the polishing liquid per unit time can be adjusted. The larger the gap, the larger the flow rate of the polishing liquid. Both ends of the coating roller shaft 72 have protrusions. There are limiting devices inside both ends of the hollow cylinder 71. The protrusions are movably connected with the limiting devices. The limiting devices are used to limit the moving range of the protrusions towards or away from the opening. In an embodiment of the present invention, the limiting device includes a chute. The extending direction of the chute faces the opening, and at least part of the protrusion is located in the chute.

[0038] Figure 3 is a partial cross-sectional schematic view of the abrasive liquid dispensing device provided by an embodiment of the present invention. Please refer to Figure 3 As shown, both ends of the coating roller shaft 72 have protrusions 721, and both ends of the inner side of the hollow cylinder 71 have chutes 711, and at least a part of the protrusions 721 is located in the chutes 711. Figure 3 The direction indicated by the arrow in is the extending direction of the chute 711, the protrusions 721 slide along the extending direction of the chute 711, and the chute 711 defines the range for the protrusions 721 to move towards or away from the opening.

[0039] In an embodiment of the present invention, the coating roller shaft 72 can rotate around its axis, and as the coating roller shaft 72 rotates, the abrasive liquid 10 flows out of the gap more evenly.

[0040] In an embodiment of the present invention, the caliber of the opening gradually increases along the extending direction of the coating roller shaft 72. Figure 4 is a schematic view of the coating roller shaft coating the abrasive liquid on the surface of the abrasive pad provided by an embodiment of the present invention. Please refer to Figure 4 As shown, the coating roller shaft 72 is located on a certain radius of the abrasive pad 2. As the abrasive pad 2 rotates, the abrasive liquid is coated on the abrasive pad 2. When the abrasive pad 2 rotates one week, the abrasive pad 2 is evenly coated with the abrasive liquid. Since the larger the radius of the abrasive pad 2, the greater the linear velocity, so from one side to the other side of the coating roller shaft 72, that is, along the direction away from the center of the abrasive pad 2, the caliber of the opening of the hollow cylinder 71 gradually increases, so that the gap between the coating roller shaft 72 and the opening gradually increases, making the coating amount of the abrasive liquid 10 less in the central area close to the abrasive pad 2 and larger in the area far from the center of the abrasive pad 2, thereby improving the uniformity of the coating of the abrasive liquid 10 on the surface of the abrasive pad 2 at each radius.

[0041] In an embodiment of the present invention, the abrasive liquid dispensing device further includes an abrasive liquid pipeline (not shown), and the abrasive liquid pipeline is communicated with the inside of the hollow cylinder 71 to supply abrasive liquid to the inside of the hollow cylinder 71.

[0042] Please continue to refer to Figure 2 , on both sides of the coating roller shaft 72 on the hollow cylinder 71, a plurality of nozzles 73 are respectively arranged for providing cleaning liquid, and the orientation of the nozzles 73 can be adjusted. When the abrasive liquid dispensing device supplies cleaning liquid to the abrasive pad, the orientation of the nozzles 73 can be adjusted. Figure 5 is a schematic view of the nozzle spraying cleaning liquid to the abrasive pad provided by an embodiment of the present invention. Please refer to Figure 2 AndFigure 5 As shown, the angle between the cleaning liquid ejected from the nozzle 73 and the polishing pad 2 is adjustable. By adjusting it to an acute angle, the high-pressure cleaning liquid in the nozzle 73 can wash the polishing pad 2 at an inclined angle, so as to flush out the impurities in the pores of the polishing pad 2, effectively clean the polishing pad 2, and reduce the scratch defects caused by residual impurities.

[0043] In this embodiment, the direction of the cleaning liquid ejected from the nozzle 73 is adjustable, that is, the angle between the cleaning liquid ejection direction and the polishing pad 2 is adjustable. The nozzle 73 is rotatably fixed on the hollow cylinder 71, and the direction of the nozzle 73 can be changed according to actual needs to provide cleaning liquid at multiple lateral angles.

[0044] Please continue to refer to Figure 2 As shown, a cleaning liquid pipeline 74 is provided in the hollow cylinder 71. The cleaning liquid pipeline 74 is communicated with a plurality of the nozzles 73 to supply the cleaning liquid to the nozzles 73. In this embodiment, the cleaning liquid can be deionized water (DIW), and the high-pressure deionized water is ejected from the nozzle 73. Of course, it is not limited to this, and other cleaning liquids known to those skilled in the art can also be used, which can be selected according to actual needs.

[0045] Please continue to refer to Figure 2 As shown, in an embodiment of the present invention, the hollow cylinder 71 is in the shape of a triangular prism. The coating roller shaft 72 is arranged on one side edge of the triangular prism, and the nozzles 73 are arranged on the adjacent two side surfaces of the triangular prism on both sides of the coating roller shaft 72. Of course, the shape of the hollow cylinder 71 is not limited to this, and other shapes known to those skilled in the art can also be used.

[0046] In an embodiment of the present invention, the material of the coating roller shaft 72 is standard special engineering plastic PPS (polyphenylene sulfide), carbon fiber reinforced PEEK (polyether ether ketone), PET-P (polyethylene terephthalate plastic), or PAI (polyamide imide), and other materials known to those skilled in the art with high temperature resistance, wear resistance, corrosion resistance, and high mechanical strength can also be used.

[0047] Correspondingly, the present invention also provides a chemical mechanical polishing device, and the chemical mechanical polishing device includes the polishing liquid distribution device as described above.

[0048] Figure 6 It is a schematic structural diagram of a chemical mechanical polishing device provided by an embodiment of the present invention. Please refer to Figure 6As shown in the figure, the chemical mechanical polishing device includes a base 8, a lifting rod 9 disposed on the base 8, and a polishing pad 2 disposed below a polishing liquid dispensing device 7. The lifting rod 9 is connected to the polishing liquid dispensing device 7 and is used to drive the polishing liquid dispensing device 7 away from the polishing pad 2, or drive the polishing liquid dispensing device 7 close to the polishing pad 2 to make the coating roller shaft 72 contact the polishing pad 2, so as to coat the polishing liquid on the polishing pad 2. The coating roller shaft 72 of the polishing liquid dispensing device 7 is arranged in the direction towards the polishing pad 2. Such an arrangement can make the polishing liquid be evenly coated on each area of the surface of the polishing pad 2 when the polishing liquid dispensing device 7 supplies the polishing liquid to the polishing pad 2.

[0049] During the chemical mechanical polishing process, lower the lifting rod 9. The lifting rod 9 drives the polishing liquid dispensing device 7 close to the polishing pad 2 to make the coating roller shaft 72 contact the surface of the polishing pad 2. Along with the rotation of the polishing pad 2, the polishing liquid is evenly coated on the polishing pad 2. After the chemical mechanical polishing process ends, raise the lifting rod 9. The lifting rod 9 drives the polishing liquid dispensing device 7 away from the polishing pad 2 to make the coating roller shaft 72 no longer contact the polishing pad 2, and stop the supply of the polishing liquid. Then, a nozzle 73 can be used to provide a lateral cleaning liquid to clean the impurities on the surface of the polishing pad 2. The angle of the lateral cleaning liquid can be adjusted according to actual needs.

[0050] Furthermore, by changing the distance that the lifting rod 9 continues to move towards the polishing pad 2 after contacting the polishing pad 2, that is, changing the moving distance of the coating roller shaft 72 in the hollow cylinder 71, the size of the gap formed between the coating roller shaft 72 and the opening of the hollow cylinder 71 can be adjusted, thereby controlling the coating amount and coating speed of the polishing liquid. For example, the greater the distance that the lifting rod 9 continues to move towards the polishing pad 2 after contacting the polishing pad 2, the greater the moving distance of the coating roller shaft 72 in the hollow cylinder 71, the greater the gap formed between the coating roller shaft 72 and the opening, the greater the coating amount of the polishing liquid, and the faster the coating speed.

[0051] In summary, in the polishing liquid dispensing device provided by the present invention, it includes a hollow cylinder and a coating roller shaft. An opening is provided on the hollow cylinder. The inside of the hollow cylinder is communicated with the outside through the opening. The hollow cylinder is used to store the polishing liquid; the coating roller shaft is arranged at the opening and can move towards or away from the opening to block the opening or form a gap with the opening. The present invention controls the outflow of the polishing liquid in the hollow cylinder by arranging the coating roller shaft at the opening of the hollow cylinder, so as to be able to evenly provide the polishing liquid.

[0052] In the chemical mechanical polishing device provided by the present invention, the lifting rod is connected to the polishing liquid distribution device, driving the polishing liquid distribution device away from the polishing pad, or driving the polishing liquid distribution device close to the polishing pad to make the coating roller shaft contact the polishing pad, so as to coat the polishing liquid on the polishing pad. With the relative rotation of the polishing pad and the polishing liquid distribution device, the polishing liquid is evenly coated on the polishing pad, so as to keep the polishing rate of the wafer stable.

[0053] In addition, a plurality of nozzles are respectively arranged on the hollow cylinders on both sides of the coating roller shaft to provide cleaning liquid. The orientation of the nozzles is adjustable, so that the cleaning liquid in the nozzles flushes the polishing pad at an inclined angle, so as to be able to flush out the impurities in the pores of the polishing pad, effectively clean the polishing pad, and reduce the scratch defects caused by residual impurities.

[0054] The above description is only a description of the preferred embodiments of the present invention, and does not limit the scope of the present invention in any way. Any changes and modifications made by those of ordinary skill in the art of the present invention according to the above disclosure shall fall within the protection scope of the claims.

Claims

1. A polishing liquid dispensing device for providing polishing liquid, characterized in that, Comprising: A hollow cylinder and a coating roller. An opening is provided on the hollow cylinder. The interior of the hollow cylinder communicates with the outside through the opening. The hollow cylinder is used for storing abrasive liquid. The coating roller is arranged at the opening and can move towards or away from the opening to block the opening or form a gap with the opening.

2. The abrasive liquid dispensing device according to claim 1, characterized in that, As the coating roller moves in the direction towards the opening, the gap gradually decreases; as the coating roller moves in the direction away from the opening, the gap gradually increases.

3. The abrasive liquid dispensing device according to claim 1, characterized in that, Both ends of the coating roller have protrusions. Inside both ends of the hollow cylinder, there are limiting devices. The protrusions are movably connected to the limiting devices. The limiting devices are used to define the range of movement of the protrusions towards or away from the opening.

4. The abrasive liquid dispensing device according to claim 3, characterized in that, The limiting device includes a chute, and at least a part of the protrusion is located in the chute.

5. The abrasive liquid dispensing device according to claim 1, characterized in that, The coating roller can rotate around its axis.

6. The abrasive liquid dispensing device according to claim 1, characterized in that, The diameter of the opening gradually increases along the extending direction of the coating roller.

7. The abrasive liquid dispensing device according to claim 1, characterized in that, The abrasive liquid dispensing device further includes an abrasive liquid pipeline, which is communicated with the interior of the hollow cylinder to supply abrasive liquid to the interior of the hollow cylinder.

8. The abrasive liquid dispensing device according to claim 1, characterized in that, On the hollow cylinder on both sides of the coating roller, a plurality of nozzles are respectively arranged for providing cleaning liquid, and the orientation of the nozzles is adjustable.

9. The abrasive liquid dispensing device according to claim 8, characterized in that, A cleaning liquid pipeline is arranged inside the hollow cylinder. The cleaning liquid pipeline is communicated with a plurality of the nozzles to supply the cleaning liquid to the nozzles.

10. The abrasive liquid dispensing device according to claim 8, wherein, The hollow cylinder is in the shape of a triangular prism. The coating roller is arranged on one edge of the triangular prism, and the nozzles are arranged on the adjacent two side faces of the triangular prism on both sides of the coating roller.

11. A chemical mechanical polishing device, characterized in that, Comprising the abrasive liquid dispensing device according to any one of claims 1 to 10, the chemical mechanical polishing device further includes a base, a lifting rod arranged on the base, and a polishing pad arranged below the abrasive liquid dispensing device. The lifting rod is connected to the abrasive liquid dispensing device and is used to drive the abrasive liquid dispensing device away from the polishing pad, or drive the abrasive liquid dispensing device close to the polishing pad so that the coating roller contacts the polishing pad to coat abrasive liquid on the polishing pad.

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