Air bag device for a grinding head

Abstract

The application discloses a kind of air bag devices for lapping head, comprising: a plurality of first bag body, the side wall of adjacent two first bag body meets, first bag body has oppositely arranged contact surface and adjustment surface, contact surface is used to contact with wafer;Second bag body is arranged in adjustment surface, at least covers the edge of one first bag body, so that the edge of first bag body is moved when second bag body deformation;Control component, including first control and second control, first control is connected to first bag body to fill medium to first bag body, so that the deformation of first bag body occurs, contact surface is attached to wafer;Second control is connected to second bag body to fill or remove medium, so that the deformation of second bag body occurs, the bottom wall of second bag body drives first bag body to move, so that contact surface is closely attached to wafer.The application can improve the pressure control at air bag interface, to further control the lapping rate at interface.

Description

Technical Field

[0001] This invention relates to the field of semiconductor processing equipment technology, and more particularly to an airbag device for a grinding head. Background Technology

[0002] Chemical mechanical polishing (CMP) is a key planarization technique in semiconductor manufacturing and is widely used in multiple process steps of integrated circuit manufacturing.

[0003] In existing technologies, polishing heads typically comprise multiple independent airbag zones, each capable of controlling the pressure in different areas to achieve precise control over material removal rates across different regions of the wafer surface. However, uneven pressure distribution at the interfaces between airbag zones can lead to variations in polishing rates. For example, if there is a difference in pressure settings between two zones, excessively high or low pressure may occur at their interfaces, resulting in abnormal removal rates in those areas. Furthermore, physical discontinuities may exist at the interfaces of the airbag zones, causing uneven stress on the wafer surface. This uneven stress can lead to uneven contact between the polishing pad and the wafer surface, affecting the uniform removal of material. Specifically, this manifests as variations in polishing rates at the interface, such as increases or decreases in removal rates, and may even result in over- or under-polishing in localized areas.

[0004] Therefore, it is necessary to provide a new airbag device for grinding heads to solve the above-mentioned problems existing in the prior art. Summary of the Invention

[0005] The purpose of this invention is to provide an airbag device for a grinding head for grinding wafer surfaces, which can improve pressure control at the airbag interface and thus further regulate the grinding rate at the interface.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: An airbag device for a grinding head, comprising: Multiple first capsules, with the sidewalls of two adjacent first capsules connected together, each first capsule having a contact surface and an adjustment surface arranged opposite to each other, the contact surface being used to contact the wafer; The second capsule is disposed on the adjustment surface and covers at least one edge of the first capsule, so that when the second capsule deforms, it drives the edge of the first capsule to move. The control component includes a first control element and a second control element. The first control element is connected to the first capsule to fill the first capsule with a medium, causing the first capsule to deform, and the contact surface is in contact with the wafer. The second control element is connected to the second capsule to fill or remove a medium from the second capsule, causing the second capsule to deform, and the bottom wall of the second capsule drives the first capsule to move so that the contact surface is in close contact with the wafer.

[0007] By adopting the above technical solution, during the grinding process, when pressurization is applied, the valve for inflation of the second bladder opens, and gas is injected into the second bladder. The positive pressure inside the bladder expands, and the pressure is precisely transmitted to the wafer surface through the contact surface of the first bladder, thereby precisely increasing the grinding rate at the contact surface. When depressurization is applied, the valve for inflation of the second bladder opens, and gas is extracted from the bladder. The negative pressure inside the bladder contracts, and the contraction force is transmitted to the wafer surface through the contact surface of the first bladder, thereby precisely reducing the grinding rate at the interface. Since the second bladder does not contact the wafer surface, the positive or negative pressure of the second bladder is mainly transmitted through the first bladder. The contact surface transmits the pressure to the wafer surface, thus allowing precise control of the grinding rate at the contact surface of the first capsule. Since the second capsule does not directly contact the wafer surface, it can be subjected to both positive and negative pressure. When the second capsule is under negative pressure, the pressure applied by the first capsule at the interface is effectively reduced, thereby decreasing the interface grinding rate. This improves the problem of uneven surface development after direct negative pressure application to the contact capsule, which can easily lead to wafer slippage and breakage. Furthermore, a small portion of the pressure in the second capsule is transmitted through the gas inside the first capsule, thus creating a pressure buffer and mitigating the problem of sudden pressure changes at the first capsule interface.

[0008] Optionally, the bottom wall of the second capsule covers the edges of the two adjacent first capsules, so that when the first capsule moves, it drives the edges of the two adjacent first capsules to move.

[0009] Optionally, a retaining ring may also be included; The inner wall of the retaining ring contacts the side wall of the first capsule, and the bottom wall of the retaining ring is used to contact the wafer to fix the wafer and adjust the pressure of the first capsule.

[0010] Optionally, the sidewall of the second capsule contacts the inner wall of the retaining ring or the sidewall of an adjacent second capsule; The bottom wall of the second capsule contacts the adjustment surface so that when the first capsule moves, it drives the edge of the outer first capsule to move.

[0011] Optionally, the second control element includes: A filling tube, one end of which is connected to the second bladder, and the other end of which is used to connect to the filling device; The extraction pipe has one end connected to the second capsule and the other end connected to the extraction device. Both the filling pipe and the extraction pipe are equipped with a first control valve to control the opening and closing of the filling pipe and the extraction pipe.

[0012] Optionally, the second control element includes: The first control conduit has one end connected to the second bladder and the other end branched out to connect the filling device and the extraction device respectively. A second control valve is located in the first control pipeline to control the opening and closing of the first control pipeline.

[0013] Optionally, the first control element includes: The second control conduit has one end connected to the first capsule and the other end connected to the filling device to fill the first capsule with a medium. A third control valve is located in the second control pipeline to control the opening and closing of the control pipeline.

[0014] Optionally, both the first and second capsules are made of flexible material so that they can deform when the pressure inside changes.

[0015] Optionally, the contact surface is provided with a pressure detection device to detect the pressure on the contact surface; When the pressure at the center of the contact surface is greater than the pressure at the edge, the second control member fills the second bladder with a medium so that the pressure at the center of the contact surface is the same as the pressure at the edge. When the pressure at the center of the contact surface is less than the pressure at the edge, the second control member removes the medium from the second capsule to make the pressure at the center of the contact surface the same as the pressure at the edge.

[0016] Optionally, the second capsule sidewall is provided with a limiting member so that when the second control member fills or removes the medium into the second capsule, the bottom surface of the second capsule can drive the first capsule to move. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an airbag device according to an embodiment of the present invention; Figure 2 This is a schematic diagram showing the positional relationship between a first airbag and a second airbag in an embodiment of the airbag device of the present invention. Figure 3 This is a schematic diagram showing the positional relationship between the first and second airbag bodies in another embodiment of the airbag device of the present invention. Figure 4This is a schematic diagram showing the positional relationship between the first and second airbag bodies in another embodiment of the airbag device of the present invention. Figure 5 This is a schematic diagram illustrating the positional relationship between a second control element and a second bladder body according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the second capsule with a limiting ring according to an embodiment of the present invention; Figure 7 A schematic diagram of the interface of the first capsule before applying positive pressure to the second capsule in this embodiment of the invention; Figure 8 for Figure 7 A schematic diagram of the pressure at the contact surface of two adjacent first bladders in the state; where the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first bladders, x2 represents the contact surface of the other first bladder; the Y-axis represents the pressure value of the contact surface; Figure 9 A schematic diagram of the pressure at the interface of the first capsule after applying positive pressure to the second capsule in an embodiment of the present invention. Figure 10 for Figure 9 A schematic diagram of the pressure at the contact surface of two adjacent first bladders in the state; where the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first bladders, x2 represents the contact surface of the other first bladder; the Y-axis represents the pressure value of the contact surface; Figure 11 A schematic diagram of the interface of the first capsule before applying negative pressure to the second capsule in this embodiment of the invention; Figure 12 for Figure 11 A schematic diagram of the pressure at the contact surface of two adjacent first bladders in the state; where the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first bladders, x2 represents the contact surface of the other first bladder; the Y-axis represents the pressure value of the contact surface; Figure 13 A schematic diagram of the pressure at the interface of the first cyst after applying negative pressure to the second cyst in an embodiment of the present invention. Figure 14 for Figure 13 A schematic diagram of the pressure at the contact surface of two adjacent first bladders in the state; where the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first bladders, and x2 represents the contact surface of the other first bladder; the Y-axis represents the pressure value of the contact surface.

[0018] Figure label: 100, First capsule; 110, Contact surface; 120, Adjustment surface; 200, Second capsule; 300, Control assembly; 310, First control element; 311, Second control conduit; 312, Third control valve; 320, Second control element; 321, Filling conduit; 322, Extraction conduit; 323, First control valve; 324, First control conduit; 325, Second control valve; 400, Limiting element; 500, Wafer; 600, Retaining ring. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects.

[0020] The following is in conjunction with the appendix Figure 1-14 The specific embodiments of the present invention will be further described in detail below.

[0021] Embodiments of the present invention provide an airbag device for a grinding head, wherein the grinding head is used to grind the surface of a wafer 500, and the airbag device is disposed at the end of the grinding head. The grinding head typically includes multiple independent airbag sections, which can control the pressure in different areas, thereby achieving precise control over the material removal rate in different areas of the wafer 500 surface. However, the grinding rate may vary at the contact surface 110 of the airbag sections due to uneven pressure distribution. To address the problem of grinding rate variations at the contact surface 110 of the airbag sections caused by uneven pressure distribution, the contact surface 110 effect, and edge effects, [further details are provided]. Figure 1 The airbag device includes: Multiple first capsules 100, with the sidewalls of two adjacent first capsules 100 connected together, and each first capsule 100 having a contact surface 110 and an adjustment surface 120 disposed opposite to each other, the contact surface 110 being used to contact the wafer 500; The second capsule 200 is disposed on the adjustment surface 120 and covers at least one edge of the first capsule 100 so that when the second capsule 200 deforms, it drives the edge of the first capsule 100 to move. The control component 300 includes a first control element 310 and a second control element 320. The first control element 310 is connected to the first capsule 100 to fill the first capsule 100 with a medium, causing the first capsule 100 to deform, and the contact surface 110 to be in contact with the wafer 500. The second control element 320 is connected to the second capsule 200 to fill or remove a medium from the second capsule 200, causing the second capsule 200 to deform, and the bottom wall of the second capsule 200 drives the first capsule 100 to move, so that the contact surface 110 is in close contact with the wafer 500.

[0022] In some embodiments, there are multiple first capsules 100, which together form a circle, with the sidewalls of two adjacent first capsules 100 connected. Therefore, when a medium is filled into the first capsule 100, the first capsule 100 deforms. When the first capsule 100 deforms, its bottom surface contacts the surface of the wafer 500. At this time, the rotation of the polishing head causes the first capsule 100 to rotate on the surface of the wafer 500, thereby polishing the surface of the wafer 500. In some specific embodiments, the first capsule 100 has a contact surface 110 and an adjustment surface 120, which are arranged opposite to each other. The contact surface 110 is used to contact the surface of the wafer 500, thereby facilitating the polishing of the wafer 500 surface by the first capsule 100. In some more specific embodiments, the upper surface of the first capsule 100 is an adjustment surface 120, and the lower surface of the first capsule 100 is a contact surface 110, wherein the contact surface 110 is used to contact the surface of the wafer 500.

[0023] In some embodiments, multiple second capsules 200 are provided, and all second capsules 200 are disposed on the adjustment surface 120. The second capsules 200 are used to assist the first capsule 100 in deformation. In some specific embodiments, the bottom surface of the second capsule 200 contacts the adjustment surface 120; more specifically, the second capsule 200 covers at least one edge of the first capsule 100.

[0024] The bottom wall of the second capsule 200 covers the edges of the two adjacent first capsules 100, so that when the first capsule 100 moves, it drives the edges of the two adjacent first capsules 100 to move.

[0025] In some specific embodiments, refer to Figure 1 A second capsule 200 is provided at the junction of the edges of two adjacent first capsules 100. The bottom surface of the second capsule 200 covers the edges of the two adjacent first capsules 100, so that when each second capsule 200 deforms, it will drive the edges of the two first capsules 100 to move.

[0026] In some embodiments, refer to Figure 2Each first capsule 100 has a second capsule 200 at its edge, so that when each second capsule 200 deforms, it will drive the edge of the corresponding first capsule 100 to move.

[0027] More specifically, after the first capsule 100 is filled with a medium, the middle part of the contact surface 110 is in contact with the surface of the wafer 500, and there is a gap between the edge of the contact surface 110 and the surface of the wafer 500, so it cannot be fully ground. At this time, the second capsule 200 is filled with a medium, and the second capsule 200 deforms. Since the bottom surface of the second capsule 200 is in contact with the adjustment surface 120, during the deformation of the second capsule 200, the adjustment surface 120 of the first capsule 100 will be moved, which in turn will move the contact surface 110 of the first capsule 100, so that the edge of the contact surface 110 is in contact with the surface of the wafer 500.

[0028] In some embodiments, the bottom surface of the second bladder 200 is fixedly disposed on the adjustment surface 120 of the first bladder 100.

[0029] When the first capsule 100 is filled with too much medium, the edges of two adjacent first capsules 100 will be squeezed, increasing the pressure of the edge of the contact surface 110 of the first capsule 100 on the surface of the wafer 500. In order to reduce the pressure on the surface of the wafer 500, the medium in the second capsule 200 can be removed. At this time, the bottom surface of the second capsule 200 moves away from the surface of the wafer 500. Since the bottom surface of the second capsule 200 is fixed to the adjustment surface 120 of the first capsule 100, during the movement of the bottom surface of the second capsule 200, the adjustment surface 120 of the first capsule 100 can be moved away from the surface of the wafer 500, thereby moving the contact surface 110 of the first capsule 100 away from the surface of the wafer 500, so that the pressure of the edge and the middle of the contact surface 110 on the surface of the wafer 500 is the same, which facilitates the grinding process.

[0030] In some embodiments, the bottom surface of the second bladder 200 and the adjustment surface 120 of the first bladder 100 can be fixed by adhesive bonding or by integral molding, without limitation, with the bottom surface of the second bladder 200 driving the adjustment surface 120 to move, thereby driving the edge of the contact surface 110 to move.

[0031] In order to facilitate the control of the deformation of the first capsule 100 and the second capsule 200, a control component 300 is also provided on the grinding head, wherein the control component 300 includes a first control element 310 and a second control element 320.

[0032] In some embodiments, the first control member 310 is connected to the first capsule 100 and is used to fill the first capsule 100 with a contact, thereby deforming the first capsule 100.

[0033] In some specific embodiments, refer to Figure 1 The first control element 310 is tubular, which allows the interior of the first control element 310 to transport the medium. The medium can enter the interior of the first capsule 100 through the first control element 310, thereby causing the first capsule 100 to deform.

[0034] In some specific embodiments, the medium is air, and the pressure of the first capsule 100 on the surface of the wafer 500 is changed by inflating the first capsule 100.

[0035] In some embodiments, refer to Figure 1 The second control element 320 is connected to the second capsule 200 and is used to fill or remove the medium into the second capsule 200, thereby causing the second capsule 200 to deform.

[0036] In some specific embodiments, the second control member 320 is tubular, enabling the interior of the second control member 320 to transport a medium. The medium can enter the interior of the second capsule 200 through the second control member 320, thereby causing the second capsule 200 to deform.

[0037] In some specific embodiments, the medium is air. By inflating the second capsule 200 or extracting gas from the second capsule 200, the pressure of the second capsule 200 on the adjustment surface 120 of the first capsule 100 is changed, thereby changing the pressure of the contact surface 110 of the first capsule 100 on the surface of the wafer 500.

[0038] Reference Figure 1 The airbag device also includes a retaining ring 600; The inner wall of the retaining ring 600 is in contact with the side wall of the first capsule 100, and the bottom wall of the retaining ring 600 is used to contact the wafer 500; so as to fix the wafer 500 and adjust the pressure of the first capsule 100.

[0039] In some embodiments, the retaining ring 600 is a ring structure and is designed around the outer edge of the wafer 500, with an inner diameter slightly larger than the diameter of the wafer 500 and an outer diameter that matches the size of the grinding head.

[0040] In some embodiments, the retaining ring 600 is made of a highly wear-resistant and highly elastic material (such as engineering plastics or composite materials), so that the retaining ring 600 can withstand grinding pressure and adapt to the positional changes of the wafer 500 through deformation.

[0041] In some embodiments, the retaining ring 600 is integrated with a plurality of first bladders 100 of the polishing head and is fixed together below the polishing head. Specifically, the inner wall of the retaining ring 600 contacts the side wall of the first bladder 100, and the bottom wall of the retaining ring 600 is used to contact the wafer 500 to fix the wafer 500 and adjust the pressure of the first bladders 100.

[0042] During the grinding process, the inner edge of the retaining ring 600 makes slight contact with the outer edge of the wafer 500, forming a physical limit to prevent lateral movement of the wafer 500. Simultaneously, the retaining ring 600, through its synergistic action with the first bladder 100, uniformly transmits the pressure at the contact point between the first bladder 100 and the sidewall of the retaining ring 600 to the edge region of the wafer 500. Furthermore, when the pressure of each first bladder is adjusted due to process requirements (such as pressurization or depressurization of the second bladder), the elastic deformation of the retaining ring 600 can absorb some pressure fluctuations, preventing abrupt changes in the grinding rate at the edge of the wafer 500. The elastic design of the retaining ring 600 also allows it to automatically adjust the clamping force when there are slight differences in the thickness of the wafer 500, avoiding localized pressure anomalies caused by unevenness of the wafer 500.

[0043] During the grinding process, the first bladder 100 of the grinding head applies main pressure by inflation, which acts directly on the surface of the wafer 500. The retaining ring 600 transmits part of the pressure to the edge of the wafer 500, while balancing the pressure distribution in the bladder zones through its own deformation.

[0044] In some embodiments, refer to Figure 3 and Figure 4 The sidewall of the second capsule 200 contacts the inner wall of the retaining ring 600 or the sidewall of the adjacent second capsule 200. The bottom wall of the second capsule 200 contacts the adjustment surface 120 so that when the first capsule 100 moves, it drives the edge of the outer first capsule 100 to move.

[0045] In some embodiments, a portion of the second bladder 200 is disposed on the adjustment surface 120 of the outermost of a plurality of first bladders 100, such that the bottom wall of the second bladder 200 contacts the adjustment surface 120 of the first bladder 100, and the side wall of the second bladder 200 contacts the side wall of the retaining ring 600; a portion of the second bladder 200 is disposed on the adjustment surface 120, and the bottom surface of the second bladder 200 simultaneously covers the connection point of two adjacent second bladders 200; at this time, the second bladder 200 deforms, and the bottom surface of the second bladder 200 contacts the side wall of the retaining ring 600. The deformation of the second bladder 200 in contact with the wall causes the first bladder 100 to move, thereby moving the edge of the contact surface 110 that contacts the inner wall of the retaining ring 600, further adjusting the pressure of the contact surface 110 at the junction of the first bladder 100 and the inner wall of the retaining ring 600 on the surface of the wafer 500; the deformation of the remaining second bladders 200 simultaneously causes the contact surfaces 110 at the junction of two adjacent first bladders 100 to move, further adjusting the pressure of the contact surfaces 110 at the junction of two adjacent first bladders 100 on the surface of the wafer 500.

[0046] In some embodiments, a portion of the second bladder 200 is disposed on the adjustment surface 120 of the outermost first bladder 100 among a plurality of first bladders 100, such that the bottom wall of the second bladder 200 contacts the adjustment surface 120 of the first bladder 100, and the side wall of the second bladder 200 contacts the side wall of the retaining ring 600; a portion of the second bladder 200 is disposed on the adjustment surface 120, and the bottom surface of the second bladder 200 covers the edge of the first bladder 100 on which it is located, while the side walls of two adjacent second bladders 200 on two adjacent first bladders 100 are in contact; at this time, the second bladder 200 deforms and conforms to the side wall of the retaining ring 600. The deformation of the second capsule 200 causes the first capsule 100 to move, causing the edge of the contact surface 110 that contacts the inner wall of the retaining ring 600 to move, further adjusting the pressure of the contact surface 110 at the junction of the first capsule 100 and the inner wall of the retaining ring 600 on the surface of the wafer 500; the deformation of the remaining second capsules 200 causes the edge of the corresponding first capsule 100 to move, and the two adjacent second capsules 200 simultaneously cause the edge of the corresponding first capsule 100 to move, further adjusting the pressure of the contact surface 110 at the junction of the two adjacent first capsules 100 on the surface of the wafer 500.

[0047] Reference Figure 5 The second control element 320 includes: The filling pipe 321 has one end connected to the second bladder 200 and the other end connected to the filling device; The extraction pipe 322 is connected at one end to the second capsule 200 and at the other end to the extraction device. Both the filling pipe 321 and the extraction pipe 322 are equipped with a first control valve 323 to control the opening and closing of the filling pipe 321 and the extraction pipe 322.

[0048] In some embodiments, one end of the filling pipe 321 is connected to the filling device, allowing the medium provided by the filling device to enter the second bladder 200 through the filling pipe, thereby regulating the pressure of the second bladder 200. Specifically, in this embodiment, the filling device is selected as an air pump, which facilitates filling the second bladder 200 with gas, thereby adding positive pressure to the inside of the second bladder 200; the extraction device is selected as a vacuum pump, which facilitates extracting the gas from the second bladder 200, thereby adding negative pressure to the inside of the second bladder 200.

[0049] In some embodiments, a first control valve 323 on the filling pipe 321 controls the opening and closing of the filling pipe 321. When the first control valve 323 controls the filling pipe 321 to open, the gas in the filling device can enter the second bladder 200 through the filling pipe 321. A first control valve 323 on the extraction pipe 322 controls the opening and closing of the extraction pipe 322. When the first control valve 323 controls the extraction pipe 322 to open, the extraction device can extract the gas in the second bladder 200, thereby regulating the pressure inside the second bladder 200.

[0050] In some embodiments, when the first control valve 323 on the filling pipe 321 is open, the first control valve 323 on the extraction pipe 322 is closed; when the first control valve 323 on the extraction pipe 322 is open, the first control valve 323 on the filling pipe 321 is closed.

[0051] In some embodiments, since there are multiple second capsules 200, there are also multiple filling pipes 321 and extraction pipes 322. In some embodiments, each filling pipe 321 is connected to a filling device, and each extraction pipe 322 is connected to an extraction device. In some embodiments, the ends of the multiple filling pipes 321 converge into a main pipeline, which is connected to the filling device and cooperates with a first control valve 323 on the filling pipe to control the gas in each filling pipe; the ends of the multiple extraction pipes converge into another main pipeline, which is connected to the extraction device and cooperates with a first control valve 323 on the extraction pipeline to control the gas in each extraction pipe.

[0052] In some embodiments, the first control valve 323 is a one-way inflation valve.

[0053] In some embodiments, the first control valve 323 is a solenoid valve.

[0054] In addition, refer to Figure 1 The second control element 320 may also include: The first control conduit 324 has one end connected to the second bladder 200, and the other end forms a branch and is used to connect the filling device and the extraction device respectively. The second control valve 325 is located in the first control pipe 324 to control the opening and closing of the first control pipe 324.

[0055] In some embodiments, one end of the first control conduit 324 is connected to the interior of the second capsule 200, and the other end forms two branch conduits, which are respectively connected to a filling device and a extraction device. When the filling device is activated, the second capsule 200 is filled with media; when the extraction device is activated, the media inside the second capsule 200 is extracted. In some embodiments, the extraction device is closed when the filling device is activated, and the filling device is closed when the extraction device is activated.

[0056] In some embodiments, the second control valve 325 controls the opening and closing of the first control pipe 324 to control the inflation or deflation process.

[0057] In some embodiments, the second control valve 325 is a two-way inflation valve to satisfy the inflation of the filling device and the degassing of the extraction device.

[0058] In some embodiments, the second control valve 325 is a solenoid valve.

[0059] In some embodiments, the second control valve 325 can adjust the size of the opening in the first control conduit 324 to regulate the rate of pressure change within the second bladder 200.

[0060] In some embodiments, each end of the second control pipe 311 corresponds to a filling device and a extraction device, respectively.

[0061] In some embodiments, the branch pipes at the ends of each second control pipe 311 that are connected to the filling device first converge into a main pipe, which is connected to the filling device, so that the branch pipes are connected to the filling device; the branch pipes at the ends of each second control pipe 311 that are connected to the extraction device first converge into a main pipe, which is connected to the extraction device, so that the branch pipes are connected to the extraction device.

[0062] Reference Figure 1 The first control element 310 includes: The second control conduit 311 has one end connected to the first capsule 100 and the other end connected to the filling device to fill the first capsule 100 with a medium. A third control valve 312 is installed on the second control pipe 311 to control the opening and closing of the second control pipe 311.

[0063] In some embodiments, the second control conduit 311 is connected to the filling device, which fills the first bladder 100 with a medium through the second control conduit 311 to regulate the pressure of the first bladder 100.

[0064] In some embodiments, the third control valve 312 is a solenoid valve to regulate the opening and closing of the second control pipe 311.

[0065] In some embodiments, the third control valve 312 is a one-way inflation valve.

[0066] To facilitate the deformation of the first capsule 100 and the second capsule 200, both the first capsule 100 and the second capsule 200 are made of flexible material, so that the first capsule 100 and the second capsule 200 can deform when the internal pressure changes.

[0067] In some embodiments, the method of fixing valves and pipelines is existing technology and will not be described in detail here.

[0068] In some embodiments, the first capsule 100 and the second capsule 200 are both made of flexible materials prepared from organic or inorganic materials.

[0069] The contact surface 110 is equipped with a pressure detection device to detect the pressure on the contact surface 110; When the pressure at the center of the contact surface 110 is greater than the pressure at the edge, the second control element 320 fills the second bladder 200 with a medium so that the pressure at the center of the contact surface 110 is the same as the pressure at the edge. When the pressure in the middle of the contact surface 110 is less than the pressure at the edge, the second control element 320 extracts the medium from the second bladder 200 so that the pressure in the middle of the contact surface 110 is the same as the pressure at the edge.

[0070] In some embodiments, the pressure detection device is used to detect the pressure on the contact surface 110, thereby detecting the pressure exerted by the contact surface 110 on the surface of the wafer 500. When the pressure at the center of the contact surface 110 is less than the pressure at the edge, it indicates that the center of the contact surface 110 is in contact with the surface of the wafer 500, and the edge has a gap with the surface of the wafer 500. When the pressure at the center of the contact surface 110 is less than the pressure at the edge, it indicates that the excessive filling of the medium in the first bladder 100 causes the edge of the contact surface 110 to be squeezed, thus increasing the pressure on the surface of the wafer 500.

[0071] In some embodiments, refer to Figure 6 In order to enable the bottom surface of the second bladder 200 to drive the first bladder 100 to move when the pressure of the second bladder 200 changes, a limiting member 400 can also be provided around the side wall of the second bladder 200. The limiting member 400 is annular and adapted to the shape of the second bladder 200. When the pressure of the second bladder 200 changes, the position of the side wall of the second bladder 200 will not change due to the limitation of the limiting member 400. At this time, the bottom surface of the second bladder 200 rises or falls to drive the edge of the first bladder 100 to move.

[0072] In some embodiments, the sidewall of the second bladder 200 is fixed to the inner wall of the limiting member 400.

[0073] In some embodiments, the shape of the first capsule 100 can be different, such as square, triangle, or circle, without limitation, as long as it can achieve the aforementioned functions.

[0074] In some embodiments, the second capsule 200 may be square, triangular, circular, or other shapes, without limitation, as long as it can achieve the aforementioned functions.

[0075] Specifically, during pressurization, the valve of the second bladder 200 opens, allowing gas to fill it. The second bladder 200 expands under positive pressure, and this pressure is precisely transmitted to the surface of the wafer 500 through the contact surface 110 of the first bladder 100, thereby precisely increasing the polishing rate at the contact surface 110. During depressurization, the valve of the second bladder 200 opens, allowing gas to be drawn out of the bladder. The bladder contracts under negative pressure, and this contraction force is transmitted to the surface of the wafer 500 through the contact surface 110 of the first bladder 100, thereby precisely reducing the polishing rate at the contact surface 110. In summary, during this process… A small portion of the pressure in the second bladder 200 is transmitted through the gas inside the first bladder 100, thus creating a pressure buffer. This improves the problem of sudden pressure changes at the contact surface 110 of the first bladder 100. At the same time, the second bladder 200 does not directly contact the wafer 500, but rather contacts the contact surface 110 of the first bladder 100. Therefore, it can apply both positive and negative pressure. When the second bladder 200 is under negative pressure, the pressure applied by the first bladder 100 at the contact surface 110 is actually reduced, thereby reducing the grinding rate of the contact surface 110. This directly solves the problem that the uneven surface caused by direct negative pressure contraction of the contact airbag can easily lead to wafer slippage and breakage.

[0076] Figure 7 A schematic diagram of the state of the contact surface 110 of the first bladder 100 before applying positive pressure to the second bladder 200. Due to the partition of the air bladder, the contact surface 110 of the air bladder is concave, which reduces the pressure and further reduces the grinding rate at the contact surface 110. Figure 8 This is a schematic diagram of the pressure at the contact surface 110 of the corresponding first bladder 100, where the pressure causes a fault at the contact surface 110; Figure 9 This diagram illustrates the state of the contact surface 110 of the first airbag 100 after positive pressure is applied to the second airbag 200. At this point, the depressions on the airbag surface are flattened, the airbag surface is smooth, the pressure is uniform, and the grinding rate is uniform. Figure 10 This is a schematic diagram of the pressure at the contact surface 110 of the corresponding first bladder 100. The pressure does not cause a fault at the contact surface 110. Figure 11 A schematic diagram of the state of the contact surface 110 of the first capsule 100 before applying negative pressure to the second capsule 200. Since a high-intensity positive pressure is applied to the first capsule 100 at this time, a small protrusion is generated at the junction of two adjacent first capsules 100, thereby increasing the pressure at the contact surface 110 and increasing the grinding rate. Figure 12 This is a schematic diagram of the pressure at the contact surface 110 of the corresponding first bladder 100, where the pressure causes a fault at the contact surface 110; Figure 13This diagram illustrates the state of the contact surface 110 of the first airbag 100 after applying negative pressure to the second airbag 200. At this point, the protrusions on the airbag surface are flattened, resulting in a smooth surface, uniform pressure, and uniform grinding rate. Figure 14 This is a schematic diagram of the pressure at the contact surface 110 of the corresponding first bladder 100. The pressure does not cause a fault at the contact surface 110.

[0077] This enables precise control of the pressure at the interface.

[0078] The principle of the airbag device for the grinding head of the present invention is as follows: during operation, air is first injected into the first bladder 100 to fix the wafer 500 and achieve the target grinding rate; then, air is injected or depressurized into the second bladder 200. The positive pressure generated by the inflation or the negative pressure generated by the depressurization can be accurately transmitted to the surface of the wafer 500 through the contact surface 110 of the first bladder 100, thereby realizing the pressure increase or depressurization at the contact surface 110, and further realizing the precise control of the grinding rate at the contact surface 110.

[0079] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. An airbag device for a grinding head, characterized in that, include: Multiple first capsules (100), with the sidewalls of two adjacent first capsules (100) connected together, each first capsule (100) having a contact surface (110) and an adjustment surface (120) disposed opposite to each other, the contact surface (110) being used to contact a wafer (500); The second capsule (200) is disposed on the adjustment surface (120) and covers at least one edge of the first capsule (100). The bottom wall of the second capsule (200) covers the edges of two adjacent first capsules (100) so that when the second capsule (200) deforms, it drives the edges of the two adjacent first capsules (100) to move. The control component (300) includes a first control element (310) and a second control element (320). The first control element (310) is connected to the first capsule (100) to fill the first capsule (100) with a medium, causing the first capsule (100) to deform. The contact surface (110) is in contact with the wafer (500). The second control element (320) is connected to the second capsule (200) to fill or remove a medium from the second capsule (200), causing the second capsule (200) to deform. The bottom wall of the second capsule (200) drives the first capsule (100) to move, so that the contact surface (110) is in close contact with the wafer (500). A retaining ring (600) has its inner wall in contact with the side wall of the first capsule (100), and its bottom wall is used to contact the wafer (500) to fix the wafer (500) and adjust the pressure of the first capsule (100); the side wall of the second capsule (200) is in contact with the inner wall of the retaining ring (600) or with the side wall of an adjacent second capsule (200); the bottom wall of the second capsule (200) is in contact with the adjusting surface (120) so that when the second capsule (200) moves, it drives the edge of the outer first capsule (100) to move; The contact surface (110) is provided with a pressure detection device to detect the pressure on the contact surface (110); When the pressure in the middle of the contact surface (110) is greater than the pressure at the edge, the second control member (320) fills the second bladder (200) with a medium so that the pressure in the middle of the contact surface (110) is the same as the pressure at the edge. When the pressure in the middle of the contact surface (110) is less than the pressure at the edge, the second control member (320) extracts the medium from the second bladder (200) so that the pressure in the middle of the contact surface (110) is the same as the pressure at the edge.

2. The airbag device according to claim 1, characterized in that, The second control element (320) includes: A filling tube (321) is connected at one end to the second bladder (200) and at the other end to the filling device; The extraction pipe (322) is connected at one end to the second capsule (200) and at the other end to the extraction device; Both the filling pipe (321) and the extraction pipe (322) are equipped with a first control valve (323) to control the opening and closing of the filling pipe (321) and the extraction pipe (322).

3. The airbag device according to claim 1, characterized in that, The second control element (320) includes: The first control conduit (324) is connected at one end to the second bladder (200) and at the other end forms a branch for connecting the filling device and the extraction device respectively; A second control valve (325) is provided in the first control pipe (324) to control the opening and closing of the first control pipe (324).

4. The airbag device according to claim 1, characterized in that, The first control element (310) includes: The second control conduit (311) is connected at one end to the first capsule (100) and at the other end to the filling device to fill the first capsule (100) with a medium. A third control valve (312) is provided in the second control pipe (311) to control the opening and closing of the control pipe.

5. The airbag device according to claim 4, characterized in that, Both the first capsule (100) and the second capsule (200) are made of flexible material so that the first capsule (100) and the second capsule (200) can deform when the pressure inside the first capsule (100) and the second capsule (200) changes.

6. The airbag device according to claim 1, characterized in that, The second capsule (200) has a limiting member (400) on its side wall so that when the second control member (320) fills or removes the medium into the second capsule (200), the bottom surface of the second capsule (200) can drive the first capsule (100) to move.

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