Chemical mechanical polishing apparatus

Abstract

The utility model discloses a chemical mechanical polishing device belongs to the field of semiconductor, the chemical mechanical polishing device at least includes: polishing head main part, with the axis of the polishing head main part as center, encircle setting in the one side of the polishing head main part, air bag, setting in the holding ring, and with the polishing head main part is connected, and the spray head combination, setting in the lateral wall of the holding ring. Through the chemical mechanical polishing device provided by the utility model, can protect the wafer surface from corrosion when the polishing device is down.

Description

Technical Field

[0001] This utility model belongs to the field of semiconductor technology, and specifically relates to a chemical mechanical polishing device. Background Technology

[0002] Chemical Mechanical Polishing (CMP) is a crucial step in semiconductor manufacturing, removing the polishing layer from wafers to achieve surface planarization. However, when a CMP unit malfunctions and shuts down, residual polishing slurry remains on the wafer surface despite the cessation of slurry supply and polishing operations. This residual slurry continues to corrode the polishing layer, creating chemical depressions. Furthermore, due to surface tension, the slurry concentrates in these depressions, further exacerbating the corrosion and resulting in uneven chemical depressions. These depressions are amplified in subsequent processing steps, ultimately leading to semiconductor device failure. Therefore, preventing residual polishing slurry from corroding the polishing layer during a Metal CMP unit shutdown is a critical technical challenge. Utility Model Content

[0003] The purpose of this invention is to provide a chemical mechanical polishing device that can protect the wafer surface from corrosion when the polishing device is shut down.

[0004] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:

[0005] This utility model provides a chemical mechanical grinding apparatus, comprising:

[0006] Grinding head body;

[0007] A retaining ring is arranged around one side of the grinding head body with the axis of the grinding head body as the center;

[0008] An airbag, disposed within the retaining ring and connected to the grinding head body; and

[0009] The nozzle assembly is disposed within the side wall of the retaining ring.

[0010] In one embodiment of the present invention, the nozzle assembly includes a plurality of nozzles, which are arranged at intervals within the side wall around the center of the retaining ring.

[0011] In one embodiment of the present invention, each nozzle includes a surface and a back surface disposed opposite to each other, the back surface being located within the sidewall, and the surface being exposed outside the retaining ring.

[0012] In one embodiment of the present invention, each of the nozzles is inclinedly disposed within the sidewall.

[0013] In one embodiment of the present invention, the plurality of nozzles include a plurality of first nozzles, which are spaced apart and disposed within the sidewall of the semi-circular side of the retaining ring.

[0014] In one embodiment of the present invention, the plurality of nozzles further includes a plurality of second nozzles, which are symmetrically arranged with respect to the first nozzles within the sidewall of the other half of the retaining ring.

[0015] In one embodiment of the present invention, the plurality of nozzles further includes a plurality of third nozzles, with at least one third nozzle disposed between adjacent first nozzles and second nozzles, between the plurality of first nozzles, and between the plurality of second nozzles.

[0016] In one embodiment of the present invention, the first nozzle is a water spray nozzle, the second nozzle is an air spray nozzle, and the third nozzle is an air spray nozzle or a liquid spray nozzle.

[0017] In one embodiment of this utility model, the coverage area of ​​the medium sprayed by each nozzle is distributed in a fan shape with the center of the nozzle as the center.

[0018] In one embodiment of this utility model, the central angle of the fan-shaped distribution is 30°-150°.

[0019] In summary, this utility model provides a chemical mechanical polishing (CMP) apparatus. Through structural improvements to the CMP apparatus, the unexpected technical effect of this application is the removal of residual polishing slurry from the layer to be polished when the polishing apparatus shuts down. This prevents the polishing slurry from continuously corroding the layer, thereby avoiding the formation of uneven chemical depressions on the wafer surface and improving wafer quality. Furthermore, the CMP apparatus provided by this utility model can form a protective layer on the layer to be polished, further preventing wafer damage when the polishing apparatus shuts down. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a chemical mechanical grinding apparatus.

[0022] Figure 2 for Figure 1Top view of the retaining ring, nozzle assembly, and wafer.

[0023] Figure 3 for Figure 2 A schematic diagram of the first nozzle.

[0024] Figure 4 for Figure 2 A schematic diagram of the second nozzle.

[0025] Figure 5 for Figure 2 A schematic diagram of the third nozzle.

[0026] Label Explanation:

[0027] 11. Grinding head body; 12. Holding ring; 13. Airbag; 14. Nozzle assembly; 141. Surface; 142. Back side; 15. First nozzle; 16. Second nozzle; 17. Third nozzle; 171. First sub-nozzle; 172. Second sub-nozzle; 173. Third sub-nozzle; 174. Fourth sub-nozzle; 18. Wafer; 181. First surface; 182. Second surface. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0030] In the description of this specification, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," and "right," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this solution and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this solution. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] Please see Figures 1 to 5As shown, this utility model provides a chemical mechanical polishing (CMP) apparatus, including, for example, a polishing head body 11, a retaining ring 12, an air bladder 13, and a nozzle assembly 14. The retaining ring 12 is arranged around one side of the polishing head body 11 with the axis of the polishing head body 11 as the center. The air bladder 13 is disposed inside the retaining ring 12 and connected to the polishing head body 11. The nozzle assembly 14 is disposed inside the side wall of the retaining ring 12. In the CMP apparatus provided by this utility model, when the polishing process is running normally, the air bladder 13 adsorbs and moves the wafer 18 to the side of the retaining ring 12 away from the polishing head body 11. The side of the wafer 18 away from the air bladder 13 is provided with the layer to be polished (not shown in the figure). The polishing liquid in the polishing liquid supply system (not shown in the figure) located outside the polishing apparatus flows onto the polishing pad (not shown in the figure) outside the polishing apparatus. At the same time, the air bladder 13 drives the wafer 18 to move to the polishing pad, so that the polishing liquid on the polishing pad is mixed with the layer to be polished. The polishing layer contacts the wafer 18 to achieve the purpose of chemical mechanical polishing of the layer to be polished. When the polishing process is stopped, the polishing slurry supply system stops outputting polishing slurry. After the airbag 13 moves the wafer 18 upward into the retaining ring 12, the nozzle assembly 14 sprays the medium onto the layer to be polished to remove the residual polishing slurry on the layer to be polished, thereby preventing the polishing slurry from continuously corroding the surface of the layer to be polished on the wafer 18, and thus preventing the formation of uneven chemical depressions on the surface of the layer to be polished on the wafer 18, protecting the layer to be polished on the wafer 18 from being damaged.

[0032] Please see Figure 1 As shown, in one embodiment of this utility model, the grinding head body 11 is used to support the retaining ring 12 and the airbag 13. The grinding head body 11 includes, for example, a drive system (not shown) and an air path control system (not shown). The drive system and the air path control system are each connected to the airbag 13. The drive system drives the airbag 13 to move, and the air path control system provides negative pressure to the airbag 13 to adsorb and fix the wafer 18.

[0033] Please see Figure 1 As shown, in one embodiment of this utility model, a retaining ring 12 is arranged around one side of the grinding head body 11 with the axis of the grinding head body 11 as the center. By providing the retaining ring 12, the wafer 18 is confined within the retaining ring 12.

[0034] Please see Figure 1 As shown, in one embodiment of this utility model, the airbag 13 is disposed within the retaining ring 12 and connected to the grinding head body 11. Specifically, the drive system and the air path control system in the grinding head body 11 are each connected to the airbag 13. The drive system drives the airbag 13 to move up and down within the retaining ring 12, and the air path control system provides negative pressure to the airbag 13 for adsorbing and fixing the wafer 18.

[0035] Please see Figure 1As shown, in one embodiment of this invention, the wafer 18 is adsorbed and connected to the side of the airbag 13 away from the polishing head body 11. The wafer 18 includes a first surface 181 and a second surface 182 disposed opposite to each other. The second surface 182 is used for direct contact with the airbag 13. The first surface 181 is located on the side of the wafer 18 away from the airbag 13. The first surface 181 is, for example, the surface of the layer to be polished, and the outer diameter of the wafer 18 is, for example, smaller than the inner diameter of the retaining ring 12. In this embodiment, the polishing apparatus is described using a metal layer as an example. Specifically, the structure of the wafer 18 includes, for example, a substrate (not shown) and a metal layer (not shown). The metal layer is disposed on the substrate, the side of the metal layer away from the substrate is the first surface 181, and the side of the substrate away from the metal layer is the second surface 182.

[0036] Please see Figures 1 to 2 As shown, in one embodiment of this utility model, in a chemical mechanical polishing apparatus, when the polishing process is running normally, under the action of the drive system and the air path control system in the polishing head body 11, the airbag 13 adsorbs and drives the wafer 18 to move to the side of the retaining ring 12 away from the polishing head body 11. After the first surface 181 is aligned with the side of the retaining ring 12 away from the polishing head body 11, the polishing liquid in the polishing liquid supply system (not shown in the figure) set outside the polishing apparatus flows onto the polishing pad (not shown in the figure) set outside the polishing apparatus. At the same time, the airbag 13 drives the wafer 18 to move to the polishing pad, so that the first surface 181 comes into contact with the polishing liquid, thereby achieving the purpose of chemical mechanical polishing of the wafer 18.

[0037] Please see Figures 1 to 2 As shown, in one embodiment of this utility model, the nozzle assembly 14 is disposed within the sidewall of the retaining ring 12. Specifically, the nozzle assembly 14 is located within the sidewall of the retaining ring 12 on the side away from the grinding head body 11, and the nozzle assembly 14 includes a plurality of nozzles, which are arranged at intervals around the center of the retaining ring 12 within the sidewall of the retaining ring 12. Each nozzle, for example, includes a surface 141 and a back surface 142 disposed opposite to each other. The back surface 142 is located within the sidewall of the retaining ring 12, while the surface 141 is exposed outside the retaining ring 12 to prevent the retaining ring 12 from blocking the surface 141, allowing the medium in the nozzle to be ejected from the surface 141. Furthermore, each nozzle is inclined inside the side wall, that is, the surface 141 and the axis of the grinding head body 11 maintain a preset angle α, for example, 5°-60°, so that when the subsequent grinding device fails, the wafer 18 can be moved so that the center of the first surface 181 is aligned with the center of the surface 141, thereby facilitating the spraying of the medium in the nozzle onto the first surface 181.

[0038] Please see Figures 1 to 5As shown, in one embodiment of this utility model, the plurality of nozzles includes a first nozzle 15 and a second nozzle 16, etc. The first nozzle 15 may be multiple, and these multiple first nozzles 15 are spaced apart within the sidewall of the semi-annular side of the retaining ring 12. Specifically, in this embodiment, there may be four first nozzles 15, which may be water spray nozzles, for example, spraying deionized water, so that when the polishing device malfunctions, the water sprayed from the water spray nozzles can wash away the residual polishing liquid on the first surface 181.

[0039] Please see Figures 1 to 5 As shown, in one embodiment of this utility model, there are, for example, multiple second nozzles 16, which are symmetrically arranged with the first nozzles 15 within the sidewall of the other half of the retaining ring 12. Specifically, in this embodiment, the number of second nozzles 16 and first nozzles 15 is equal, for example, four. The second nozzle 16 is, for example, an air jet nozzle, and the gas ejected by the air jet nozzle is, for example, an inert gas. By providing the second nozzle 16, after the water ejected from the first nozzle 15 washes away the residual polishing liquid on the first surface 181, the gas ejected from the second nozzle 16 can blow away the water on the first surface 181.

[0040] Please see Figures 1 to 5As shown, in another embodiment of this utility model, the nozzle further includes a third nozzle 17. For example, there may be multiple third nozzles 17, with at least one third nozzle 17 disposed between adjacent first nozzles 15 and second nozzles 16, between multiple first nozzles 15, and between multiple second nozzles 16. Specifically, in this embodiment, there may be four third nozzles 17, including, for example, a first sub-nozzle 171, a second sub-nozzle 172, a third sub-nozzle 173, and a fourth sub-nozzle 174. The first sub-nozzle 171 and the second sub-nozzle 172 are respectively disposed between adjacent first nozzles 15 and second nozzles 16, and the first nozzles 15 and the second nozzles 16 are symmetrically distributed with the line connecting the center of the first sub-nozzle 171 and the center of the second sub-nozzle 172 as the center. Furthermore, a third sub-nozzle 173 is disposed between the first nozzles 15, and a fourth sub-nozzle 174 is disposed between the second nozzles 16. The line connecting the center of the third sub-nozzle 173 and the center of the fourth sub-nozzle 174 is perpendicular to the line connecting the center of the first sub-nozzle 171 and the center of the second nozzle 172. Further, the third nozzle 17 is, for example, a liquid spray nozzle or an air spray nozzle. When the third nozzle 17 is a liquid spray nozzle, the sprayed liquid is, for example, a passivating liquid. In this embodiment, the passivating liquid includes, for example, at least one alkaline liquid such as trimethylamine, dimethylamine, and its derivatives. When the third nozzle 17 is an air spray nozzle, the sprayed gas includes, for example, at least one of nitrogen-containing gas and silane. The nitrogen-containing gas includes, for example, at least one of nitrous oxide, nitrogen dioxide, and nitric oxide. By providing the third nozzle 17, after the second nozzles 16 purge and remove water from the first surface 181, a passivation protective layer can be formed on the first surface 181, protecting the first surface 181.

[0041] Please see Figures 1 to 5 As shown, in one embodiment of this utility model, in the first nozzle 15, the second nozzle 16, and the third nozzle 17, the coverage area of ​​the medium sprayed by each nozzle is distributed in a fan shape with the center of the nozzle as the center. The central angle of the fan shape is, for example, 30°-150°. Specifically, in this embodiment, for the first nozzle 15, the central angle of the fan shape of the sprayed water is, for example, 60°; for the second nozzle 16, the central angle of the fan shape of the sprayed gas is, for example, 90°; and for the third nozzle 17, the central angle of the fan shape of the sprayed liquid or gas is, for example, 120°.

[0042] Please see Figures 1 to 5As shown in one embodiment of this utility model, in a chemical mechanical polishing apparatus, when the apparatus malfunctions, i.e., the polishing process is stopped midway, the polishing slurry supply system stops outputting polishing slurry. The airbag 13 moves the wafer 18 upwards into the retaining ring 12, making the first surface 181 higher than the nozzle assembly 14, and aligning the center of each nozzle surface 141 with the center of the first surface 181. Water is then sprayed from one side of the wafer 18 onto the first surface 181 through the first nozzle 15. The water causes the residual polishing slurry on the first surface 181 to detach from the other side of the wafer 18, preventing the polishing slurry from continuously corroding the metal layer in the first surface 181. Then, water spraying stops. Next, inert gas is sprayed from the other side of the wafer 18 onto the first surface 181 through the second nozzle 16. The inert gas causes the water on the first surface 181 to detach from one side of the wafer 18. Then, inert gas spraying stops. Finally, passivating liquid or gas is sprayed onto the first surface 181 from four directions through four third nozzles 17. The passivating liquid or gas forms a uniform passivation protective layer on the first surface 181, thereby preventing uneven chemical depressions from forming on the first surface 181 and protecting the wafer 18 from damage.

[0043] In summary, this utility model provides a chemical mechanical polishing (CMP) apparatus. By incorporating a first nozzle and a second nozzle within the sidewall of the retaining ring, the unexpected technical effect of this application is that it can remove residual polishing slurry from the wafer's surface to be polished when the CMP apparatus malfunctions, preventing the polishing slurry from continuously corroding the metal layer and thus avoiding the formation of uneven chemical depressions on the wafer surface, thereby improving wafer quality. Furthermore, the CMP apparatus provided by this utility model, by incorporating a third nozzle within the sidewall of the retaining ring, can form a protective layer on the wafer's surface to be polished, further preventing wafer damage when the polishing apparatus malfunctions.

[0044] The embodiments of this utility model disclosed above are merely illustrative of the present utility model. The embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Obviously, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.

Claims

1. A chemical mechanical grinding apparatus, characterized in that, At least including: Grinding head body; A retaining ring is arranged around one side of the grinding head body with the axis of the grinding head body as the center; An airbag, disposed within the retaining ring and connected to the grinding head body; and The nozzle assembly is disposed within the side wall of the retaining ring.

2. The chemical mechanical grinding apparatus according to claim 1, characterized in that, The nozzle assembly includes multiple nozzles, which are arranged at intervals within the sidewall around the center of the retaining ring.

3. The chemical mechanical grinding apparatus according to claim 2, characterized in that, Each of the nozzles includes a surface and a back surface disposed opposite to each other, the back surface being located within the sidewall, and the surface being exposed outside the retaining ring.

4. The chemical mechanical grinding apparatus according to claim 2, characterized in that, Each of the nozzles is angled within the sidewall.

5. The chemical mechanical grinding apparatus according to claim 2, characterized in that, The plurality of nozzles includes a plurality of first nozzles, which are spaced apart within the sidewall of the semi-circular side of the retaining ring.

6. The chemical mechanical grinding apparatus according to claim 5, characterized in that, The plurality of nozzles also include a plurality of second nozzles, which are symmetrically arranged with respect to the first nozzles within the sidewall of the other half of the retaining ring.

7. The chemical mechanical grinding apparatus according to claim 6, characterized in that, The plurality of nozzles also include a plurality of third nozzles, with at least one of the third nozzles disposed between adjacent first nozzles and second nozzles, between the plurality of first nozzles, and between the plurality of second nozzles.

8. The chemical mechanical grinding apparatus according to claim 7, characterized in that, The first nozzle is a water spray nozzle, the second nozzle is an air spray nozzle, and the third nozzle is an air spray nozzle or a liquid spray nozzle.

9. The chemical mechanical grinding apparatus according to claim 2, characterized in that, The coverage area of ​​the medium sprayed by each nozzle is distributed in a fan shape with the center of the nozzle as the center.

10. The chemical mechanical grinding apparatus according to claim 9, characterized in that, The central angle of the fan-shaped distribution is 30°-150°.

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