Polishing ring and chemical mechanical grinding device
By setting grooves and through holes on the lower surface of the polishing ring, the problem of uneven distribution of the abrasive liquid is solved, and more uniform wafer grinding and higher product performance and yield are achieved.
Patent Information
- Application Number
- CN202422244230.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-12
- Publication Date
- 2025-07-29
- Estimated Expiration
- 2034-09-12
AI Technical Summary
In existing chemical mechanical grinding devices, the abrasive liquid is unevenly distributed on the wafer surface, resulting in poor chemical mechanical grinding effect, affecting the performance and manufacturing yield of wafer products.
A groove and through through holes are provided on the lower surface of the ring body of the polishing ring. The abrasive liquid enters the groove through the through holes and is distributed to the surface of the abrasive pad to ensure that the abrasive liquid is evenly covered before the wafer reaches.
It improves the uniformity of wafer grinding, improves the quality of chemical mechanical grinding, and improves the performance and manufacturing yield of wafer products.
Smart Images
Figure CN223160722U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a polishing ring and a chemical mechanical polishing device. Background Art
[0002] Chemical Mechanical Polish (CMP) process is a planarization process. Since it was introduced into the integrated circuit manufacturing process in 1990, through continuous practice and development, it has become a key process to promote the continuous reduction of the integrated circuit technology node. In today's rapidly developing semiconductor manufacturing industry, chemical mechanical polishing is an advantageous and superior method for planarizing and polishing a semiconductor substrate to remove excess material above the surface of the semiconductor substrate. During chemical mechanical polishing, a chemical solution mixed with extremely fine abrasive grains reacts chemically with the processing surface to change the chemical bonds on its surface, generating products that are easily removed mechanically. Then, the chemical reactants are removed by mechanical friction to obtain a super-smooth and damage-free planarized surface.
[0003] The current chemical mechanical polishing device includes a polishing pad, a polishing head located on the polishing pad, a polishing ring located below the polishing head for fixing a wafer, and a polishing liquid nozzle located above the polishing pad. The polishing liquid nozzle sprays polishing liquid onto the polishing pad, and the polishing liquid is dispersed on the polishing pad under the action of centrifugal force, and chemical mechanical polishing is carried out through the contact between the wafer and the polishing liquid. However, only through the action of centrifugal force, the polishing liquid will be unevenly distributed on the surface of the wafer. For example, the polishing liquid does not contact the wafer, resulting in uneven reaction between the wafer and the polishing liquid and affecting the effect of chemical mechanical polishing.
[0004] Therefore, how to improve the effect of chemical mechanical polishing is a technical problem that needs to be solved urgently at present. Summary of the Invention
[0005] The utility model provides a polishing ring and a chemical mechanical polishing device, which are used to improve the effect of chemical mechanical polishing and enhance the performance and manufacturing yield of wafer products.
[0006] According to some embodiments, the utility model provides a polishing ring, including:
[0007] A ring body, the ring body includes an upper surface and a lower surface that are oppositely distributed in a first direction, and the ring body is used to fix the wafer to be polished;
[0008] A groove, the groove is located on the lower surface of the ring body;
[0009] A through hole, the through hole penetrates the ring body along the first direction, and the through hole communicates with the groove.
[0010] In some embodiments, the ring body includes an inner ring region for fixing the wafer to be polished and a ring body region distributed around the inner ring region, and the groove penetrates through the ring body region in the radial direction of the ring body.
[0011] In some embodiments, the grooves are symmetrically distributed around the projection of the through hole on the lower surface of the ring body.
[0012] In some embodiments, the groove is in an arc shape protruding towards the through hole in the first direction.
[0013] In some embodiments, the number of the grooves is multiple, the number of the through holes is multiple, and the multiple grooves are in one-to-one communication with the multiple through holes;
[0014] The multiple grooves are evenly distributed on the lower surface of the ring body.
[0015] According to some other embodiments, the present invention further provides a chemical mechanical polishing device, including:
[0016] A polishing pad;
[0017] A polishing ring located above the polishing pad, the polishing ring including a ring body, a groove, and a through hole, the ring body including an upper surface and a lower surface oppositely distributed in a first direction, the ring body being used for fixing the wafer to be polished, the groove being located on the lower surface of the ring body, the through hole penetrating through the ring body in the first direction, and the through hole communicating with the groove.
[0018] In some embodiments, the ring body includes an inner ring region for fixing the wafer to be polished and a ring body region distributed around the inner ring region, and the groove penetrates through the ring body region in the radial direction of the ring body.
[0019] In some embodiments, the through hole is directly above the groove in the first direction.
[0020] In some embodiments, the groove is in an arc shape protruding towards the through hole in the first direction.
[0021] In some embodiments, it further includes:
[0022] A transmission structure located above the polishing pad, the transmission structure being used for transmitting polishing liquid to the through hole.
[0023] The polishing ring and chemical mechanical polishing device provided by the present utility model are such that by providing a groove on the lower surface of the ring body of the polishing ring and providing a through hole that penetrates the ring body in a first direction and communicates with the groove, the polishing liquid can enter the groove through the through hole, a part of the polishing liquid in the groove can be transmitted to the surface of the polishing pad below the polishing ring through the groove, and another part of the polishing liquid in the groove can be transmitted to the surface of the polishing pad outside the polishing ring through the groove, so that the surface of the polishing pad can be evenly and sufficiently covered with the polishing liquid before the wafer arrives, thereby improving the uniformity of wafer polishing, improving the quality of chemical mechanical polishing, and realizing the improvement of the performance and manufacturing yield of the wafer product. Description of the Drawings
[0024] Figure 1 is a top view schematic diagram of the polishing ring in the specific embodiment of the present utility model;
[0025] Figure 2 is a bottom view schematic diagram of the polishing ring in the specific embodiment of the present utility model;
[0026] Figure 3 is a partial cross-sectional schematic diagram of the polishing ring in the specific embodiment of the present utility model;
[0027] Figure 4 is a top view schematic diagram of the chemical mechanical polishing device in the specific embodiment of the present utility model;
[0028] Figure 5 is a partial cross-sectional schematic diagram of the chemical mechanical polishing device in the specific embodiment of the present utility model. Specific Embodiment
[0029] The following describes in detail the specific embodiments of the polishing ring and chemical mechanical polishing device provided by the present utility model with reference to the accompanying drawings.
[0030] This specific embodiment provides a polishing ring. Figure 1 is a top view schematic diagram of the polishing ring in the specific embodiment of the present utility model, Figure 2 is a bottom view schematic diagram of the polishing ring in the specific embodiment of the present utility model, Figure 3 is a partial cross-sectional schematic diagram of the polishing ring in the specific embodiment of the present utility model. As Figures 1 - 3 shown, the polishing ring includes:
[0031] A ring body 10, the ring body 10 includes an upper surface 101 and a lower surface 102 that are oppositely distributed in a first direction, and the ring body 10 is used to fix the wafer to be polished;
[0032] A groove 20, the groove 20 is located on the lower surface of the ring body 10;
[0033] A through hole 11 that penetrates the ring body 10 along the first direction, and the through hole 11 communicates with the groove 20.
[0034] Specifically, the polishing ring is disposed below the polishing head, and the wafer to be polished is placed in the inner region P1 of the ring. The polishing ring is used to fix the wafer to be polished. During chemical mechanical polishing, the polishing head applies a pressure to the wafer to be polished through the polishing ring to press the wafer to be polished against the surface of the polishing pad. At the same time, the polishing head drives the wafer to be polished to reciprocate on the surface of the polishing pad to achieve chemical mechanical polishing through the contact between the wafer to be polished and the polishing liquid on the surface of the polishing pad. By providing the groove 20 and the through hole 11 communicating with the groove 20 on the ring body 10, the polishing liquid can be transmitted from above the polishing ring to the groove 20 through the through hole 11. A part of the polishing liquid in the groove 20 can be transmitted to the surface of the polishing pad below the ring body 10 through the groove 20, and another part of the polishing liquid in the groove 20 can overflow to the surface of the polishing pad outside the polishing ring through the groove 20, so that the surface of the polishing pad can be evenly and sufficiently covered with the polishing liquid before the wafer to be polished arrives, thereby improving the polishing uniformity of the wafer to be polished and improving the quality of chemical mechanical polishing, and realizing the improvement of the performance and manufacturing yield of the wafer product.
[0035] In some embodiments, the ring body 10 includes an inner ring region P1 for fixing the wafer to be polished and a ring body region P2 distributed around the inner ring region P1, and the groove 20 penetrates the ring body region P2 along the radial direction of the ring body 10.
[0036] Specifically, the annular region surrounded by the ring body 10 is the inner ring region P1, and the ring body region P2 is distributed around the outer periphery of the inner ring region P1. The inner ring region P1 is used to fix the wafer to be polished. By making the groove 20 penetrate the ring body region P2 along the radial direction of the ring body 10, the length of the groove 20 along the radial direction of the ring body 10 can be increased, so as to increase the area of the polishing liquid in contact with the polishing pad below the ring body 10, and through the pressure applied by the polishing ring towards the surface of the polishing pad, the polishing liquid on the surface of the polishing pad can be further smeared evenly, so as to further improve the polishing uniformity of the wafer to be polished.
[0037] In some embodiments, the grooves 20 are symmetrically distributed around the projection of the through hole 11 on the lower surface of the ring body 10, so as to further improve the uniformity of the distribution of the polishing liquid on the surface of the polishing pad.
[0038] In some embodiments, the groove 20 is in an arc shape protruding towards the through hole 10 along the first direction.
[0039] Specifically, the groove 20 is in an arc shape protruding towards the through hole 10 along the first direction, that is, the groove 20 arches towards the through hole 10 and is in an arch shape, so that more of the abrasive liquid can be retained in the groove 20. On the one hand, it enables the surface of the polishing pad (especially the surface of the polishing pad below the ring body 10) to be covered by more of the abrasive liquid before the wafer to be polished arrives, thereby ensuring sufficient reaction between the wafer to be polished and the abrasive liquid to further ensure the effect of chemical mechanical polishing; on the other hand, since more of the abrasive liquid is retained in the groove 20, it can reduce the influence of the centrifugal force generated by the rotation of the polishing head and the rotation of the polishing pad on the abrasive liquid, thereby further improving the uniformity of the distribution of the abrasive liquid on the surface of the polishing pad.
[0040] In some embodiments, the number of the grooves 20 is multiple, the number of the through holes 11 is multiple, and the multiple grooves 20 communicate with the multiple through holes 11 one by one;
[0041] The multiple grooves 20 are evenly distributed on the lower surface of the ring body 10.
[0042] Specifically, the ring body 10 of the polishing ring has multiple grooves 20 symmetrically distributed about the center of the ring body 10 and multiple through holes 11 corresponding to the multiple grooves 20 one by one. By providing multiple grooves 20 and multiple through holes 11 evenly distributed on the ring body 10, on the one hand, it can increase the amount of the abrasive liquid distributed around the wafer to be polished and ensure the sufficiency of polishing; on the other hand, it can increase the amount of the abrasive liquid below the ring body 10, so that the abrasive liquid can be further evenly and sufficiently covered on the surface of the polishing pad by the pressure of the ring body 10, thereby further enabling the wafer to be polished to contact the abrasive liquid evenly, and further improving the uniformity of polishing. The term "multiple" as described in this specific embodiment means more than two.
[0043] This specific embodiment also provides a chemical mechanical polishing device, Figure 4 which is a top view schematic diagram of the chemical mechanical polishing device in the specific embodiment of the present invention, Figure 5 and is a partial cross-sectional schematic diagram of the chemical mechanical polishing device in the specific embodiment of the present invention. Among them, Figure 5 the solid arrows in represent the flow direction of the abrasive liquid. The structure of the polishing ring in the chemical mechanical polishing device can be referred to Figures 1 - 3As shown in Figures 1 - 5 the chemical mechanical polishing apparatus includes:
[0044] a polishing pad 40;
[0045] a polishing ring located above the polishing pad 40, the polishing ring including a ring body 10, a groove 20, and a through hole 11. The ring body 10 includes an upper surface and a lower surface that are oppositely distributed in a first direction. The ring body 10 is used to fix a wafer to be polished. The groove 20 is located on the lower surface of the ring body 10. The through hole 11 penetrates the ring body 10 along the first direction, and the through hole 11 communicates with the groove 20.
[0046] Specifically, the chemical mechanical polishing apparatus includes a polishing table, the polishing pad 40 located on the polishing table, a polishing head located on the polishing pad 40, and the polishing ring located below the polishing head. During the chemical mechanical polishing process, the wafer to be polished is fixed below the polishing head through the polishing ring. The polishing table drives the polishing pad 40 to rotate, and the polishing head applies a pressure to the wafer to be polished through the polishing ring to press the wafer to be polished against the surface of the polishing pad. At the same time, the polishing head drives the wafer to be polished to reciprocate on the surface of the polishing pad to achieve chemical mechanical polishing through the contact between the wafer to be polished and the polishing liquid on the surface of the polishing pad. The polishing liquid is transmitted to the groove 20 through the through hole 11. A part of the polishing liquid in the groove 20 can be transmitted to the surface of the polishing pad below the ring body 10 through the groove 20, and another part of the polishing liquid in the groove 20 can overflow to the surface of the polishing pad outside the polishing ring through the groove 20, so that the surface of the polishing pad can be evenly and sufficiently covered with the polishing liquid before the wafer to be polished arrives, thereby improving the polishing uniformity of the wafer to be polished and improving the quality of chemical mechanical polishing, and realizing the improvement of the performance and manufacturing yield of the wafer product.
[0047] In some embodiments, the ring body 10 includes a ring inner region P1 for fixing the wafer to be polished and a ring body region P2 distributed around the ring inner region P1. The groove 20 penetrates the ring body region P2 in the radial direction of the ring body 10.
[0048] Specifically, by making the groove 20 penetrate the ring body area P2 along the radial direction of the ring body 10, the length of the groove 20 along the radial direction of the ring body 10 can be increased, thereby increasing the area of the polishing liquid in contact with the polishing pad below the ring body 10. Through the pressure applied by the polishing ring towards the surface of the polishing pad, the polishing liquid on the surface of the polishing pad can be further spread evenly, so as to further improve the polishing uniformity of the wafer to be polished.
[0049] In some embodiments, the through hole 11 is located directly above the groove 20 along the first direction.
[0050] In some embodiments, the groove 20 has an arc shape protruding towards the through hole 11 along the first direction.
[0051] In some embodiments, the chemical mechanical polishing device further includes:
[0052] A transmission structure, located above the polishing pad 40, for transmitting the polishing liquid to the through hole 11.
[0053] Specifically, the through hole 11 includes an outlet facing the groove 20 and communicating with the groove 20, and an inlet opposite to the outlet along the first direction. The polishing liquid is transmitted to the inlet of the through hole 11 through the transmission structure, and then transmitted to the groove 20 through the outlet of the through hole 11. Among them, the transmission structure can be a diversion tube or a nozzle, etc., as long as it can transmit the polishing liquid into the through hole 11 from the inlet of the through hole 11.
[0054] The polishing ring and the chemical mechanical polishing device provided by this specific embodiment are provided with grooves on the lower surface of the ring body of the polishing ring, and through holes that penetrate the ring body along the first direction and communicate with the grooves, so that the polishing liquid can enter the grooves through the through holes. A part of the polishing liquid in the grooves can be transmitted to the surface of the polishing pad below the polishing ring through the grooves, and another part of the polishing liquid in the grooves can be transmitted to the surface of the polishing pad outside the polishing ring through the grooves, so that the surface of the polishing pad can be evenly and fully covered with the polishing liquid before the wafer arrives, so as to improve the polishing uniformity of the wafer, thereby improving the quality of chemical mechanical polishing and realizing the improvement of the performance and manufacturing yield of the wafer product.
[0055] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.
Claims
1. A polishing ring, characterized in that, Comprising: A ring body, the ring body comprising an upper surface and a lower surface that are oppositely distributed in a first direction, the ring body being used for fixing a wafer to be polished; A groove, the groove being located on the lower surface of the ring body; A through hole, the through hole penetrating the ring body in the first direction, and the through hole being communicated with the groove.
2. The polishing ring according to claim 1, wherein The ring body comprises a ring inner region for fixing the wafer to be polished and a ring body region distributed around the ring inner region, and the groove penetrates the ring body region in the radial direction of the ring body.
3. The polishing ring according to claim 1, wherein, The grooves are symmetrically distributed around the projection of the through hole on the lower surface of the ring body.
4. The polishing ring according to claim 1, characterized in that, The groove is in an arc shape protruding towards the through hole in the first direction.
5. The polishing ring according to claim 1, characterized in that, The number of the grooves is multiple, the number of the through holes is multiple, and the multiple grooves are communicated with the multiple through holes one by one; The multiple grooves are evenly distributed on the lower surface of the ring body.
6. A chemical mechanical polishing device, characterized in that, Comprising: A polishing pad; A polishing ring, located above the polishing pad, the polishing ring comprising a ring body, a groove and a through hole, the ring body comprising an upper surface and a lower surface that are oppositely distributed in a first direction, the ring body being used for fixing a wafer to be polished, the groove being located on the lower surface of the ring body, the through hole penetrating the ring body in the first direction, and the through hole being communicated with the groove.
7. The chemical mechanical polishing apparatus according to claim 6, characterized in that, The ring body comprises a ring inner region for fixing the wafer to be polished and a ring body region distributed around the ring inner region, and the groove penetrates the ring body region in the radial direction of the ring body.
8. The chemical mechanical polishing apparatus according to claim 6, wherein The through hole is located directly above the groove in the first direction.
9. The chemical mechanical polishing apparatus according to claim 6, wherein, The groove is in an arc shape protruding towards the through hole in the first direction.
10. The chemical mechanical polishing apparatus according to claim 6, wherein, Further comprising: A transmission structure, located above the polishing pad, the transmission structure being used for transmitting polishing liquid to the through hole.