Carrying head for chemical mechanical polishing and chemical mechanical polishing apparatus

Abstract

The utility model relates to chemical mechanical polishing technical field, specifically disclose a bearing head for chemical mechanical polishing and chemical mechanical polishing equipment. The bearing head includes the face pressure air bag module along the vertical direction extension, face pressure air bag module includes face pressure elastic film, trimming support plate and gasket, the gasket is pasted in the bottom end of trimming support plate, face pressure elastic film wraps trimming support plate and gasket, the bottom end of face pressure elastic film is formed with the contact surface parallel to horizontal plane, and the contact surface is used for abutting the wafer, the projection profile of trimming support plate in horizontal plane is located in the projection profile of gasket in horizontal plane. The bearing head is through the optimization design to specific structure, realizes the controllable adjustment to wafer edge area, increases the effective use area of wafer, and promotes the stability and uniformity of chemical mechanical polishing process.

Description

Technical Field

[0001] This utility model relates to the field of chemical mechanical polishing technology, and in particular to a bearing head and chemical mechanical polishing equipment for chemical mechanical polishing. Background Technology

[0002] In semiconductor integrated circuit manufacturing processes, global wafer planarization is one of the key steps in achieving high-density, high-performance integrated circuits. Among these processes, chemical mechanical polishing (CMP) is a core technique for achieving ultra-precision wafer surface processing and is widely used in the planarization of structures such as interlayer dielectrics, metal layers, and shallow trench isolation.

[0003] In traditional chemical mechanical polishing (CMP) processes, a support head is typically used to adsorb the wafer and apply a load, bringing it into contact with a rotating polishing pad. With the assistance of the polishing slurry, material removal and surface planarization are achieved. The core structure of the support head usually includes an elastic membrane, support components, and a vacuum adsorption system. Pressure distribution applied to the wafer surface is controlled by air pressure adjustment, thereby regulating the overall planarization effect of the wafer.

[0004] However, in existing technologies, especially in the chemical mechanical polishing (CMP) process of 6-inch wafers, the carrier head structure has several significant technical defects that limit wafer processing accuracy and the expansion of the effective area. Firstly, the trimming support plate and gasket structure used in traditional carrier heads easily form localized sealed cavities when wrapped in an elastic membrane. This leads to uneven pressure distribution at the wafer edge, resulting in uncontrollable pressure-free areas (i.e., cavity areas) and creating a large area of ​​ineffective edge regions (typically 3mm-5mm per side). This ineffective area not only reduces the effective usable area of ​​the wafer but may also affect subsequent wafer edge trimming, dicing, and packaging processes, with the negative impact being particularly pronounced in the manufacturing of highly integrated chips.

[0005] Secondly, as semiconductor processes evolve towards higher integration and smaller feature sizes, the requirements for wafer surface flatness are increasing, especially in the manufacturing of 4-inch and 6-inch wafers. The ability to control local pressure in the wafer edge region has become a key factor affecting the overall polishing uniformity. However, traditional bearing head structures lack independent pressure adjustment capabilities for the edge region, making it difficult to meet the needs of selective adsorption and local pressure optimization. This results in poor consistency of wafer surface flattening, and even problems such as edge collapse or stress concentration.

[0006] Furthermore, existing bearing head structures have poor compatibility, making it difficult to adapt to the high-precision polishing requirements of wafers of different sizes or different material systems, thus limiting the versatility and process adaptability of the equipment. Especially in applications requiring high flatness, such as bonded wafers, traditional bearing heads struggle to achieve good parallel adhesion between the lower surface of the wafer and the polishing pad, thereby affecting polishing uniformity and surface defect control.

[0007] In summary, the existing carrier head structure has significant shortcomings in terms of wafer edge pressure control, ineffective region control, and process compatibility, and there is an urgent need for a new type of carrier head for chemical mechanical polishing. Utility Model Content

[0008] The purpose of this invention is to provide a carrier head and chemical mechanical polishing equipment for chemical mechanical polishing, so as to achieve controllable adjustment of the wafer edge area, increase the effective usable area of ​​the wafer, and improve the stability and uniformity of the chemical mechanical polishing process.

[0009] To achieve this objective, the present invention adopts the following technical solution:

[0010] A carrier head for chemical mechanical polishing selectively adsorbs wafers. The carrier head for chemical mechanical polishing includes a surface pressure airbag module extending vertically. The surface pressure airbag module includes a surface pressure elastic membrane, a trimming support plate, and a gasket. The gasket is attached to the bottom end of the trimming support plate. The surface pressure elastic membrane wraps around the trimming support plate and the gasket. The bottom end of the surface pressure elastic membrane forms a contact surface parallel to the horizontal plane, which is used to abut the wafer. The projected outline of the trimming support plate in the horizontal plane is located within the projected outline of the gasket in the horizontal plane.

[0011] As an optional technical solution for the bearing head used in chemical mechanical polishing, the bearing head for chemical mechanical polishing further includes an adsorption control module. The adsorption control module is located above the surface pressure airbag module. The top end of the surface pressure elastic membrane is fixed to the adsorption control module, and the surface pressure elastic membrane and the adsorption control module form a surface pressure chamber. The adsorption control module is configured to pressurize or depressurize the surface pressure chamber, so that the trimming support plate squeezes the gasket to adjust the morphology of the contact surface.

[0012] As an optional technical solution for the bearing head used in chemical mechanical polishing, the surface pressure airbag module also includes a retainer, which is disposed outside the surface pressure chamber and sleeved on the outer side of the top end of the trimming support plate; the surface pressure elastic membrane passes through the intersecting surface between the top end of the trimming support plate and the retainer, and extends around the outer edge of the trimming support plate.

[0013] As an optional technical solution for the bearing head used in chemical mechanical polishing, the top of the trimming support plate is provided with an air venting groove, and the center of the bottom end of the trimming support plate is provided with a cylindrical groove extending in a vertical direction. The bottom of the cylindrical groove is provided with an annular groove, which is coaxially arranged with the cylindrical groove. The outer side of the annular groove is coplanar with the side of the cylindrical groove. The trimming support plate is provided with a plurality of air venting channels, which connect the annular groove and the air venting groove.

[0014] As an optional technical solution for the bearing head used in chemical mechanical polishing, the air passage includes a connecting groove and an air passage hole. The air passage hole passes through the trimming support plate. The connecting groove is opened at the bottom of the cylindrical groove. One end of the connecting groove is opened on the inner side of the annular groove, and the other end is opened on the wall of the air passage hole.

[0015] As an optional technical solution for the bearing head used in chemical mechanical polishing, the air vent extends vertically and the connecting groove extends radially along the trimming support plate.

[0016] As an optional technical solution for the bearing head used in chemical mechanical polishing, all of the air passages are evenly distributed at circumferential intervals along the trimming support plate.

[0017] As an optional technical solution for the bearing head used in chemical mechanical polishing, the adsorption control module further includes an air supply component, a flange connection component, a lifting elastic membrane, and a main body component. The flange connection component, the lifting elastic membrane, and the main body component are connected in sequence to form a lifting chamber. The air supply component can pressurize or depressurize the lifting chamber, causing the main body component to move closer to or further away from the flange connection component. The surface pressure elastic membrane is connected to the bottom end of the main body component.

[0018] As an optional technical solution for the bearing head used in chemical mechanical polishing, the bottom end of the main body component is also provided with several trimming chambers, which are located in the lifting chamber. The air supply component can pressurize or depressurize the trimming chamber, so that the cavity wall of the trimming chamber squeezes the gasket to adjust the shape of the contact surface.

[0019] A chemical mechanical polishing (CMP) apparatus includes a dresser, a slurry supply device, a polishing pad, and a bearing head for CMP, wherein the polishing pad is used to support the wafer, the slurry supply device is used to spray polishing slurry onto the surface of the polishing pad, and the dresser is used to shape the surface of the polishing pad.

[0020] The beneficial effects of this utility model are:

[0021] This bearing head for chemical mechanical polishing utilizes a surface pressure elastic membrane within a surface pressure airbag module to wrap a trimming support plate and a gasket, forming a contact surface that contacts the wafer. This allows for full-area and uniform pressure distribution on the wafer surface, better transferring pressure and preventing wafer deformation or damage caused by localized stress concentration. This significantly improves wafer adsorption stability and uniformity, resulting in more consistent and stable wafer surface planarization. The structure allows for independent control of surface pressure in different areas. Particularly at the wafer edges, the trimming support plate and gasket work together to achieve localized depressurization or pressurization adjustment, meeting selective adsorption requirements. The projected contour of the trimming support plate lies within the projected contour of the gasket, ensuring that the area within the surface pressure elastic membrane on the contact surface is fully loaded, avoiding cavities, reducing ineffective edge areas, and expanding the effective processing area of ​​the wafer. This increases the effective usable area of ​​the wafer, making it particularly suitable for high-precision processes such as bonding wafers, contributing to improved polishing quality and product yield. Meanwhile, the contact surface is parallel to the horizontal plane, ensuring good parallel contact and adhesion between the lower surface of the wafer and the polishing pad. This improves the flatness and consistency of the wafer surface during chemical mechanical polishing and avoids pressure concentration or loss in edge areas due to uneven support. The modularly designed surface pressure airbag module can adapt to the high-precision polishing requirements of wafers of different sizes, improving the versatility and compatibility of the equipment.

[0022] This chemical mechanical polishing (CMP) equipment integrates a bearing head, dresser, slurry supply device, and polishing pad for CMP, forming a complete closed-loop polishing process. It achieves highly efficient collaborative operation throughout the entire wafer polishing process, from wafer adsorption, positioning, polishing to release, improving process automation and efficiency, and realizing the integration and automation of the entire wafer polishing process. The dresser can perform real-time dressing and activation of the polishing pad, maintaining its surface morphology uniformity and activity; the slurry supply device ensures that the slurry evenly covers the polishing pad surface, promoting the chemical reaction; and the bearing head for CMP, through its multi-chamber pressure control system, achieves uniform pressure and adsorption on the wafer surface, thereby achieving high-precision polishing of the wafer surface and improving the quality and consistency of the polished surface. The overall equipment has a compact structure, strong functional synergy, and extremely high process adaptability and production efficiency, significantly improving the flatness, bonding, and overall yield of wafer bonding, and enhancing the processing quality and yield of high-end products such as bonded wafers. Attached Figure Description

[0023] Figure 1 This is an exploded view of the support head for chemical mechanical polishing provided in an embodiment of this utility model;

[0024] Figure 2 This is a top view of the carrier head for chemical mechanical polishing provided in an embodiment of the present invention;

[0025] Figure 3 yes Figure 2 Cross-sectional view of plane AA;

[0026] Figure 4 yes Figure 3 A magnified view of part B in the image;

[0027] Figure 5 yes Figure 4 A magnified view of part C;

[0028] Figure 6 This is an exploded view of the surface pressure airbag module provided in this embodiment of the utility model;

[0029] Figure 7 This is a schematic diagram of the trimming support plate provided in an embodiment of the present utility model;

[0030] Figure 8 This is a bottom view of the trimming support plate provided in this embodiment of the utility model;

[0031] Figure 9 yes Figure 8 Cross-sectional view of the DD plane.

[0032] In the picture:

[0033] 100. Bearing head for chemical mechanical polishing; 110. Top cover; 120. Flange connection assembly; 121. Connecting flange; 122. Air passage cavity; 1221. First air passage; 1222. Second air passage; 1223. Third air passage; 123. Sealing pressure ring; 131. Bearing seat; 132. Trimming elastic membrane; 140. Surface pressure airbag module; 141. Surface pressure elastic membrane; 142. Cage; 143. Damping ring; 144. Trimming support plate; 1441. Connecting groove; 1442. Cylindrical groove; 1443. Annular groove; 1444. Air vent; 1445. Air vent groove; 145. Gasket; 150. Retaining ring; 160. First locking element; 170. Second locking element; 180. Lifting elastic membrane;

[0034] 900, wafer. Detailed Implementation

[0035] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0036] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Moreover, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0037] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0038] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0039] like Figures 1 to 9 As shown, this embodiment provides a chemical mechanical polishing (CMP) apparatus, including a dresser, a slurry supply device, a polishing pad, and a bearing head 100 for CMP polishing. The polishing pad is used to support a wafer 900, the slurry supply device is used to spray polishing slurry onto the surface of the polishing pad, and the dresser is used to shape the surface of the polishing pad.

[0040] This chemical mechanical polishing (CMP) equipment integrates a carrier head 100, a dresser, a slurry supply device, and a polishing pad for CMP, forming a complete closed-loop polishing process. It achieves highly efficient collaborative operation throughout the entire wafer 900 polishing process, from wafer 900 adsorption, positioning, polishing to release, improving the level of process automation and efficiency, and realizing the integration and automation of the entire wafer 900 polishing process. The dresser can perform real-time dressing and activation of the polishing pad, maintaining the uniformity and activity of its surface morphology; the slurry supply device ensures that the slurry evenly covers the surface of the polishing pad, promoting the chemical reaction; and the carrier head 100 for CMP, through its multi-chamber pressure control system, achieves uniform pressure and adsorption on the wafer 900 surface, thereby achieving high-precision polishing of the wafer 900 surface and improving the quality and consistency of the polished surface. The overall equipment has a compact structure and strong functional synergy, with extremely high process adaptability and production efficiency. It significantly improves the flatness, bonding and overall yield of wafer 900 bonding, and improves the processing quality and yield of high-end products such as bonded wafer 900.

[0041] This equipment is compatible with polishing various sizes of 900 wafers. Through the modular design of the carrier head 100 used for chemical mechanical polishing (CMP), it is easy to upgrade and expand, enhancing the compatibility and scalability of the CMP equipment and improving its adaptability to complex 900 wafer materials and structures. Furthermore, the structure of this CMP equipment facilitates the integration of sensors and control systems, supporting process data acquisition and feedback control, aligning with the development trend of intelligent manufacturing and supporting intelligent manufacturing and data acquisition.

[0042] This embodiment also provides a carrier head 100 for chemical mechanical polishing (CMP), applied to the aforementioned CMP equipment. The carrier head 100 selectively adsorbs wafers 900. The carrier head 100 includes a surface pressure airbag module 140 extending vertically. The surface pressure airbag module 140 includes a surface pressure elastic membrane 141, a trimming support plate 144, and a gasket 145. The gasket 145 is attached to the bottom end of the trimming support plate 144. The surface pressure elastic membrane 141 wraps around the trimming support plate 144 and the gasket 145. The bottom end of the surface pressure elastic membrane 141 forms a contact surface parallel to the horizontal plane, which is used to abut against the wafer 900. The projection outline of the trimming support plate 144 in the horizontal plane is located within the projection outline of the gasket 145 in the horizontal plane.

[0043] The bearing head 100 for chemical mechanical polishing utilizes a surface pressure elastic membrane 141 within a surface pressure airbag module 140 to wrap a trimming support plate 144 and a gasket 145, forming a contact surface with the wafer 900. This allows for full-area and uniform pressure distribution on the wafer 900 surface, better transferring pressure to the wafer 900 surface and preventing deformation or damage caused by localized stress concentration. This significantly improves the adsorption stability and uniformity of the wafer 900, resulting in more consistent and stable surface planarization. The aforementioned structure supports independent control of surface pressure in different areas. Particularly in the wafer 900 edge region, the trimming support plate 144 and the gasket 145 work synergistically to achieve localized depressurization or pressurization adjustment in the edge region, meeting selective adsorption requirements. The projected contour of the trimming support plate 144 lies within the projected contour of the pad 145, ensuring that the contact surface fully generates load within the area of ​​the surface pressure elastic membrane 141, avoiding cavity areas, reducing ineffective edge areas, and expanding the effective processing area of ​​the wafer 900. This increases the effective usable area of ​​the wafer 900, making it particularly suitable for high-precision processes such as bonding wafers 900, and helping to improve polishing quality and product yield. Simultaneously, the contact surface is parallel to the horizontal plane, ensuring good parallel contact and adhesion between the lower surface of the wafer 900 and the polishing pad, improving the flatness and consistency of the wafer 900 surface during chemical mechanical polishing, and preventing pressure concentration or loss in edge areas due to uneven support. Through the modular design of the surface pressure airbag module 140, it can adapt to the high-precision polishing requirements of wafers 900 of different sizes, improving the versatility and compatibility of the equipment.

[0044] In this embodiment, wafer 900 is preferably a 4-inch or 6-inch wafer 900.

[0045] In this embodiment, the bearing head 100 for chemical mechanical polishing also includes an adsorption control module. The adsorption control module is located above the surface pressure airbag module 140. The top end of the surface pressure elastic membrane 141 is fixed to the adsorption control module, and the surface pressure elastic membrane 141 and the adsorption control module form a surface pressure chamber. The adsorption control module is configured to pressurize or depressurize the surface pressure chamber, so that the trimming support plate 144 squeezes the pad 145 to adjust the shape of the contact surface.

[0046] The adsorption control module and the surface pressure elastic membrane 141 form a surface pressure chamber. By pressurizing or depressurizing the surface pressure chamber, the degree of compression of the surface pressure elastic membrane 141 on the trimming support plate 144 and the gasket 145 can be dynamically adjusted, changing the pressure distribution on the surface of the wafer 900. This achieves precise control of the contact surface morphology and realizes dynamic pressure feedback and adjustment. This module can independently control the adsorption state, and the wafer 900 can be firmly adsorbed below the contact surface, realizing flexible control of wafer 900 adsorption and release. This prevents slippage and displacement during the polishing process and avoids wafer 900 damage caused by traditional rigid contact. It is suitable for processing high-precision, high-value wafers 900, further ensuring processing accuracy and operational safety. During the adsorption stage, pressurization ensures that the contact surface fully adheres to the wafer 900, and during the release stage, depressurization reduces the adsorption force, improving the reliability and efficiency of wafer 900 adsorption and release. For bonded wafers 900 or wafers 900 with non-uniform surfaces, the above structure can achieve local pressure compensation and adaptive bonding by adjusting the surface pressure distribution, improving process stability. During the polishing process, by adjusting the adsorption pressure, the wafer 900 and the polishing pad can maintain optimal contact, ensuring the adhesion between the wafer 900 and the polishing pad, improving polishing efficiency and surface quality, and enhancing the flatness control accuracy and consistency of the wafer 900 surface during the polishing process. The rapid response capability of the surface pressure chamber significantly enhances the adaptability of the carrier head 100 for chemical mechanical polishing to different wafer 900 thicknesses, curvatures, and surface conditions, enabling the carrier head 100 for chemical mechanical polishing to quickly adjust its state in different process stages (such as pre-pressure, polishing, and release), improving the flexibility and stability of the process.

[0047] Furthermore, the surface pressure airbag module 140 also includes a retainer 142, which is located outside the surface pressure chamber and is sleeved on the outer side of the top end of the trimming support plate 144; the surface pressure elastic membrane 141 passes through the intersecting surface between the top end of the trimming support plate 144 and the retainer 142, and extends around the outer edge of the trimming support plate 144.

[0048] The retainer 142 reinforces and positions the structure of the trimming support plate 144 and the surface-pressure elastic membrane 141, improving equipment assembly efficiency and consistency, and optimizing component assembly processability. Specifically, the retainer 142, fitted outside the trimming support plate 144, limits the membrane's deformation range, enhancing the structural stability and sealing performance of the surface-pressure elastic membrane 141. This ensures controllable movement during pressurization or depressurization, preventing the elastic membrane from shifting, twisting, or over-expanding under high pressure or high-frequency operation. It also improves the structural stability and deformation control of the surface-pressure elastic membrane 141, reducing wear and fatigue during repeated stretching, improving the durability and maintenance cycle of the entire chemical mechanical polishing equipment, and extending the service life and reliability of the surface-pressure elastic membrane 141. Simultaneously, the optimized fit between the retainer 142 and the trimming support plate 144 optimizes the stress distribution of the surface-pressure elastic membrane 141, reducing localized stress concentration and allowing it to act more evenly on the gasket 145 and the wafer 900 surface under pressure, improving pressure transmission efficiency and morphology control. The intersecting surfaces between the retainer 142 and the trimming support plate 144 effectively isolate different pressure areas, enhance structural sealing and isolation, prevent air pressure cross-contamination, and improve the reliability of the chemical mechanical polishing equipment.

[0049] Specifically, a damping ring 143 is also sandwiched between the retainer 142 and the trimming support plate 144. The damping ring 143 is a conventional feature in the art, and its specific structure and working principle are common knowledge in the art. Moreover, the damping ring 143 is not the focus of this embodiment, and will not be described in detail here.

[0050] Furthermore, the top of the trimming support plate 144 is provided with an air vent 1445, and the center of the bottom end of the trimming support plate 144 is provided with a cylindrical groove 1442. The cylindrical groove 1442 extends vertically, and the bottom of the cylindrical groove 1442 is provided with an annular groove 1443. The annular groove 1443 is coaxially arranged with the cylindrical groove 1442, and the outer side of the annular groove 1443 is coplanar with the side of the cylindrical groove 1442. The trimming support plate 144 is provided with several air vents, and the air vents connect the annular groove 1443 and the air vent 1445.

[0051] By setting air vents 1445, cylindrical grooves 1442, and annular grooves 1443 on the trimming support plate 144, a multi-path gas flow structure is constructed, achieving efficient gas flow and pressure distribution control. This improves the flow velocity and uniformity of gas pressure distribution within the trimming support plate 144, optimizes the gas flow path and pressure transmission efficiency, and avoids local pressure imbalances caused by gas pressure stagnation or uneven distribution. This enhances the adhesion accuracy and consistency of the surface pressure elastic membrane 141 to the wafer 900 surface, improves the gas pressure response speed, and achieves a more stable pressure response, further improving the polishing effect. Simultaneously, the above design reduces airflow resistance, accelerates gas pressure transmission speed, and makes the carrier head 100 used for chemical mechanical polishing more sensitive to pressurization or depressurization commands, shortening the response time of the chemical mechanical polishing equipment, improving the response speed of the carrier head 100 to gas pressure changes, and increasing process efficiency. The design of the cylindrical groove 1442 and the annular groove 1443 helps to enhance the sealing between the trimming support plate 144 and the flange connection assembly 120, prevent air pressure leakage, improve control accuracy, and enhance airtightness and sealing control capabilities. In particular, the limited position of the annular groove 1443 makes the pressure distribution in the edge area controllable, further improving the planarization accuracy of the edge area of ​​the wafer 900.

[0052] Furthermore, the air passage includes a connecting groove 1441 and an air vent 1444. The air vent 1444 passes through the trimming support plate 144. The connecting groove 1441 is opened at the bottom of the cylindrical groove 1442. One end of the connecting groove 1441 is opened on the inner side of the annular groove 1443, and the other end is opened on the wall of the air vent 1444.

[0053] By dividing the air passage into a connecting groove 1441 and an air outlet 1444, a multi-segment airflow channel structure is constructed, achieving an optimized layout of the air pressure path. This makes the airflow path easier to control, facilitating adjustments and optimizations based on different process requirements, and improving the accuracy and flexibility of airflow path control. This structure allows air pressure to enter the air outlet 1444 more quickly from the annular groove 1443 via the connecting groove 1441, ensuring the stable operation of the surface pressure elastic membrane 141 under complex conditions and reducing process deviations caused by air pressure delays or uneven distribution. Simultaneously, the multi-segment airflow channel structure allows for segmented application and control of air pressure in different areas, improving the uniformity and controllability of pressure distribution. Furthermore, the separate design of the connecting groove 1441 and the air outlet 1444 facilitates manufacturing and assembly, improving production efficiency and structural reliability, enhancing structural machining accuracy and assembly convenience, and helping to strengthen control over the contact surface edges. It is suitable for mass production and maintenance replacement, with a compact structure and high processing feasibility.

[0054] In this embodiment, the air vent 1444 extends vertically, and the connecting groove 1441 extends radially along the trimming support plate 144.

[0055] Radial grooves facilitate the uniform transmission of air pressure from the center to the edge, while axial holes enable vertical pressure transmission, improving the pressure uniformity on the wafer 900 surface and enhancing the uniform distribution of air pressure. Limiting the axial extension of the venting holes 1444 and the radial extension of the connecting grooves 1441 helps construct a more rational airflow path, allowing air pressure to be evenly distributed throughout the entire support structure in the shortest possible time. This makes the air pressure distribution more three-dimensional and spatial, thereby improving overall pressure-driven efficiency and forming a three-dimensional airflow distribution network. The three-dimensional airflow structure can cope with different pressure gradients and process parameter variations, improving the process adaptability and stability of the carrier head 100 used for chemical mechanical polishing (CMP), and enhancing its adaptability to complex pressure environments. The aforementioned directional design effectively reduces airflow resistance, thereby improving the response speed and accuracy of the carrier head 100 for CMP in controlling the pressure on the wafer 900 surface.

[0056] For example, all the air passages are evenly distributed along the circumferential intervals of the trimmed support plate 144.

[0057] The uniform distribution structure ensures that the air pressure is evenly distributed in all directions, enabling differentiated pressure control in different areas of the wafer 900. This avoids uneven pressure on the wafer 900 surface caused by airflow asymmetry, improves the circumferential symmetry and consistency of the air pressure distribution, and helps reduce vibration and imbalance caused by air pressure fluctuations. The uniform distribution design not only improves the overall stability of the carrier head 100 used for chemical mechanical polishing, but also enhances the process consistency and repeatability of the carrier head 100 used for chemical mechanical polishing during the polishing process, which is conducive to achieving process standardization.

[0058] In this embodiment, the adsorption control module also includes an air supply component, a flange connection component 120, a lifting elastic membrane 180, and a main body component. The flange connection component 120, the lifting elastic membrane 180, and the main body component are connected in sequence to form a lifting chamber. The air supply component can pressurize or depressurize the lifting chamber, causing the main body component to move closer to or further away from the flange connection component 120. The surface pressure elastic membrane 141 is connected to the bottom end of the main body component.

[0059] The lifting chamber, formed by the flange connection assembly 120, the lifting elastic diaphragm 180, and the main body assembly, enables the vertical movement control of the bearing head 100 used for chemical mechanical polishing (CMP). The pressure within the lifting chamber is controlled by the air supply assembly, driving the main body assembly to move vertically to adapt to the requirements of multi-stage polishing processes. This facilitates the adsorption, polishing, and release of the wafer 900, allowing for dynamic adjustment of the overall height of the bearing head 100. The lifting control function enables fine-tuning and precise control of the contact pressure, improving the polishing quality and consistency of the wafer 900 and enhancing the contact control accuracy between the bearing head 100 and the polishing pad. The lifting elastic diaphragm 180, with its excellent resilience, combined with the precision air supply assembly, enables rapid and accurate vertical displacement control, improving the response speed and accuracy of the CMP equipment. The flange connection assembly 120 ensures good sealing between components, preventing air pressure leakage, improving the operational stability of the CMP equipment, and enhancing structural sealing and stability.

[0060] The aforementioned structure significantly enhances the adaptability, versatility, and versatility of the carrier head 100 for chemical mechanical polishing to different processing stages (such as contact, pressure, and separation), strengthens its ability to adapt to complex grinding processes, and improves the intelligence and automation level of chemical mechanical polishing equipment.

[0061] Furthermore, the bottom of the main component is provided with several trimming chambers, which are located within the lifting chamber. The air supply component can pressurize or depressurize the trimming chambers, causing the chamber walls of the trimming chambers to squeeze the gaskets 145 to adjust the morphology of the contact surface. Specifically, the bottom of the support 131 is connected to several trimming elastic membranes 132, which together with the support 131 form trimming chambers. The trimming support plate 144 has through-holes through which the trimming elastic membranes 132 pass.

[0062] Multiple trimming chambers are located at the bottom of the main component, allowing the air supply component to independently pressurize or depressurize them. This enables localized pressure adjustment of the gasket 145 and the contact surface edge area, adjusting the morphology of the contact surface edge area. This effectively reduces unevenness and scratches in the edge area, ensuring consistent edge treatment for each wafer 900 during polishing. It refines the control capability of the wafer 900 edge area, improves edge flattening, achieves independent pressure control of the edge area, improves process repeatability and yield, enhances polishing consistency and repeatability, and improves the polishing quality and utilization efficiency of the wafer 900 edge area. This function is particularly suitable for trimming and polishing the wafer 900 edge area, effectively controlling the width of ineffective edge areas, enhancing the polishing quality and utilization rate of the wafer 900 edge area, and improving the overall effective area utilization of the wafer 900. Simultaneously, through independent control of the trimming chambers, differentiated pressure distribution in the wafer 900 edge area can be achieved, meeting the diverse needs of high-precision polishing processes.

[0063] Exemplarily, the main component includes a top cover 110, a support base 131, a retaining ring 150, a plurality of first locking members 160, and a plurality of second locking members 170. The retaining ring 150 is fixed to the bottom end of the support base 131 via the first locking members 160. A portion of the surface pressure elastic membrane 141 is clamped between the retaining ring 150 and the support base 131 to fix the adsorption control module to the surface pressure elastic membrane 141, and the retaining ring 150 is sleeved on the outside of the gasket 145. The top cover 110 is fixed to the top end of the support base 131 via the second locking members 170. A portion of the lifting elastic membrane 180 is clamped between the top cover 110 and the support base 131 to fix the main component to the lifting elastic membrane 180. Specifically, both the first locking members 160 and the second locking members 170 are bolts.

[0064] In this embodiment, the flange connection assembly 120 includes a connecting flange 121, an air passage cavity 122, and a sealing ring 123. The connecting flange 121 is fixed to the top end of the air passage cavity 122 for connecting external components. The sealing ring 123 is fixed to the bottom end of the air passage cavity 122, and a portion of the lifting elastic membrane 180 is clamped between the sealing ring 123 and the air passage cavity 122 to fix the main component and the lifting elastic membrane 180. The air passage cavity 122 has a first air passage 1221, a second air passage 1222, and a third air passage 1223. The air supply assembly pressurizes or depressurizes the lifting chamber through the first air passage 1221, pressurizes or depressurizes the trimming chamber through the second air passage 1222, and pressurizes or depressurizes the pressure chamber through the third air passage 1223.

[0065] When the air supply component pressurizes the second air passage 1222, the pressure enters the trimming chamber, and the trimming elastic membrane 132 transmits the pressure to the trimming support plate 144, driving the surface pressure airbag module 140 to move downward.

[0066] Before the polishing process, the air supply component is used to pressurize the third air channel 1223 so that the pressure enters the surface pressure chamber. The surface pressure airbag module 140 transmits the pressure to the entire surface of the wafer 900, so that the lower surface of the wafer 900 is completely in contact with the polishing pad. The polishing fluid flows into the surface of the polishing pad, and the polishing pad and the bearing head rotate in the same direction to enter the space between the wafer 900 and the polishing pad to carry out a chemical reaction, ultimately achieving the ultra-precision polishing process.

[0067] After the polishing process is completed, the air supply component pressurizes the second air channel 1222, and the pressure enters the trimming chamber. The air supply component evacuates the third air channel 1223, and the vacuum enters the surface pressure chamber, so that the surface pressure elastic membrane 141 and the clearance hole form a vacuum chamber, causing the wafer 900 to be adsorbed on the bottom end of the surface pressure elastic membrane 141. Then the air supply component evacuates the first air channel 1221, causing the carrier 131 and the surface pressure airbag module 140 to move upward.

[0068] In this embodiment, the specific structure and working principle of the lifting chamber and the trimming chamber are common knowledge in the field, and the lifting chamber and the trimming chamber are not the focus of this embodiment, so they will not be described in detail here.

[0069] By working together in the surface pressure chamber, lifting chamber, and trimming chamber, the differential pressure dynamic adjustment of wafer 900 in different regions can be achieved. This helps to achieve consistent pressure control between the edge and center regions of wafer 900, so as to meet complex process requirements, improve process consistency and wafer 900 quality stability, adapt to multiple process requirements, and support complex process paths.

[0070] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A carrier head for chemical mechanical polishing, selectively adsorbing wafers (900), characterized in that, The bearing head for chemical mechanical polishing includes a surface pressure airbag module (140) extending vertically. The surface pressure airbag module (140) includes a surface pressure elastic membrane (141), a trimming support plate (144), and a gasket (145). The gasket (145) is attached to the bottom end of the trimming support plate (144). The surface pressure elastic membrane (141) wraps around the trimming support plate (144) and the gasket (145). The bottom end of the surface pressure elastic membrane (141) forms a contact surface parallel to the horizontal plane, which is used to abut against the wafer (900). The projection outline of the trimming support plate (144) in the horizontal plane is located within the projection outline of the gasket (145) in the horizontal plane.

2. The bearing head for chemical mechanical polishing according to claim 1, characterized in that, The bearing head for chemical mechanical polishing also includes an adsorption control module, which is located above the surface pressure airbag module (140). The top end of the surface pressure elastic membrane (141) is fixed to the adsorption control module, and the surface pressure elastic membrane (141) and the adsorption control module form a surface pressure chamber. The adsorption control module is configured to pressurize or depressurize the surface pressure chamber, so that the trimming support plate (144) squeezes the pad (145) to adjust the shape of the contact surface.

3. The bearing head for chemical mechanical polishing according to claim 2, characterized in that, The surface pressure airbag module (140) also includes a retainer (142), which is located outside the surface pressure chamber and is sleeved on the outer side of the top end of the trimming support plate (144). The surface pressure elastic membrane (141) passes through the intersecting surface between the top end of the trimming support plate (144) and the retainer (142) and extends around the outer edge of the trimming support plate (144).

4. The bearing head for chemical mechanical polishing according to claim 3, characterized in that, The top of the trimming support plate (144) is provided with an air passage groove (1445), and the center of the bottom end of the trimming support plate (144) is provided with a cylindrical groove (1442). The cylindrical groove (1442) extends vertically, and the bottom of the cylindrical groove (1442) is provided with an annular groove (1443). The annular groove (1443) and the cylindrical groove (1442) are coaxially arranged. The outer side of the annular groove (1443) is coplanar with the side of the cylindrical groove (1442). The trimming support plate (144) is provided with a plurality of air passages, and the air passages connect the annular groove (1443) and the air passage groove (1445).

5. The bearing head for chemical mechanical polishing according to claim 4, characterized in that, The air passage includes a connecting groove (1441) and an air passage hole (1444). The air passage hole (1444) passes through the trimming support plate (144). The connecting groove (1441) is opened at the bottom of the cylindrical groove (1442). One end of the connecting groove (1441) is opened on the inner side of the annular groove (1443), and the other end is opened on the wall of the air passage hole (1444).

6. The bearing head for chemical mechanical polishing according to claim 5, characterized in that, The air vent (1444) extends vertically, and the connecting groove (1441) extends radially along the trimming support plate (144).

7. The bearing head for chemical mechanical polishing according to claim 4, characterized in that, All of the air passages are evenly distributed along the circumferential intervals of the trimmed support plate (144).

8. The bearing head for chemical mechanical polishing according to claim 2, characterized in that, The adsorption control module further includes an air supply component, a flange connection component (120), a lifting elastic membrane (180), and a main body component. The flange connection component (120), the lifting elastic membrane (180), and the main body component are connected in sequence to form a lifting chamber. The air supply component can pressurize or depressurize the lifting chamber, causing the main body component to move closer to or further away from the flange connection component (120). The surface pressure elastic membrane (141) is connected to the bottom end of the main body component.

9. The carrier head for chemical mechanical polishing according to claim 8, characterized in that, The bottom end of the main component is also provided with several trimming chambers, which are located in the lifting chamber. The air supply component can pressurize or depressurize the trimming chamber, so that the cavity wall of the trimming chamber squeezes the gasket (145) to adjust the shape of the contact surface.

10. A chemical mechanical polishing device, characterized in that, The device includes a dresser, a slurry supply device, a polishing pad, and a bearing head for chemical mechanical polishing as described in any one of claims 1-9, wherein the polishing pad is used to support the wafer (900), the slurry supply device is used to spray polishing slurry onto the surface of the polishing pad, and the dresser is used to shape the surface of the polishing pad.

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