Air bag device for grinding head

Abstract

The invention discloses an air bag device for a grinding head, which comprises a plurality of first bag bodies, the side walls of two adjacent first bag bodies are connected, each first bag body is provided with a contact surface and an adjusting surface which are oppositely arranged, and the contact surfaces are used for being in contact with a wafer; the second bag body is arranged on the adjusting surface and at least covers the edge of one first bag body, so that the edge of the first bag body is driven to move when the second bag body deforms; the control assembly comprises a first control piece and a second control piece, the first control piece is connected to the first capsule body so as to fill the first capsule body with a medium to enable the first capsule body to deform, and the contact surface is attached to the wafer; and the second control piece is connected to the second capsule body to fill the second capsule body with the medium or extract the medium from the second capsule body, so that the second capsule body deforms, and the bottom wall of the second capsule body drives the first capsule body to move, so that the contact surface is tightly attached to the wafer. The pressure control on the air bag interface can be improved, so that the grinding rate on the interface is further regulated and controlled.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor processing equipment, and in particular to an air bag device for a grinding head. Background Art

[0002] Chemical mechanical polishing is a key planarization technology in the semiconductor manufacturing process and is widely used in multiple process steps in integrated circuit manufacturing.

[0003] In the prior art, the grinding head usually includes a plurality of independent airbag partitions, which can respectively control the pressure of different areas, thereby realizing precise control of the material removal rate of different areas on the wafer surface. However, the interface of the airbag partitions may cause changes in the grinding rate due to the uneven pressure distribution. For example, if there is a difference in the pressure setting between the two partitions, the local pressure may be too high or too low at their interface, resulting in an abnormal removal rate in the area. In addition, there may be physical discontinuities at the interface of the airbag partitions, resulting in uneven force on the wafer surface. This uneven force may cause uneven contact of the grinding pad with the wafer surface, thereby affecting the uniform removal of the material. Specifically, changes in the grinding rate may occur at the partition interface, such as an increase or decrease in the removal rate, and may even lead to over-grinding or under-grinding of local areas.

[0004] Therefore, it is necessary to provide a new airbag device for a grinding head to solve the above problems in the prior art. Summary of the invention

[0005] The object of the present invention is to provide an airbag device for a grinding head for grinding the surface of a wafer, which can improve the pressure control at the airbag interface, thereby further regulating the grinding rate at the interface.

[0006] To achieve the above object, the technical solution of the present invention is as follows: An air bag device for a grinding head, comprising: A plurality of first capsules, side walls of two adjacent first capsules are connected, the first capsules have a contact surface and an adjustment surface that are oppositely arranged, and the contact surface is used to contact the wafer; A second capsule is disposed on the adjustment surface and covers at least one edge of the first capsule, so that when the second capsule is deformed, the edge of the first capsule is driven to move; The control component includes a first control component and a second control component. The first control component is connected to the first capsule to fill the first capsule with a medium to cause the first capsule to deform, and the contact surface is in contact with the wafer. The second control component is connected to the second capsule to fill or extract a medium from the second capsule to cause 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 pressurizing, the valve for inflating the second capsule opens, gas is filled into the second capsule, the positive pressure inside the capsule expands, and the pressure is accurately transmitted to the wafer surface through the contact surface of the first capsule, thereby accurately increasing the grinding rate at the contact surface; when depressurizing, the valve for inflating the second capsule opens, gas is extracted from the capsule, the negative pressure inside the capsule contracts, and the contraction force is transmitted to the wafer surface through the contact surface of the first capsule, thereby accurately reducing the grinding rate at the interface; since the second capsule does not contact the wafer surface, the positive or negative pressure of the second capsule is mainly transmitted through the first capsule. The contact surface is transmitted to the wafer surface, so the grinding rate at the contact surface of the first capsule can be accurately controlled. At the same time, since the second capsule is not in direct contact with the wafer surface, not only positive pressure but also negative pressure can be applied to the second capsule. When the second capsule is under negative pressure, the pressure applied by the first capsule is actually reduced at the interface, thereby reducing the interface grinding rate and improving the problem of wafer slip and breakage caused by the uneven surface after the contact airbag is directly contracted under negative pressure. In addition, a small part of the pressure of the second capsule is transmitted through the gas inside the first capsule, thus generating a pressure buffer, thereby improving the problem of sudden pressure changes at the interface of the first capsule.

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

[0009] Optionally, a retaining ring is also included; The inner wall of the retaining ring contacts the side wall of the first sac, and the bottom wall of the retaining ring contacts the wafer, so as to fix the wafer and adjust the pressure of the first sac.

[0010] Optionally, the side wall of the second capsule contacts the inner wall of the retaining ring or contacts the side wall of an adjacent second capsule; The bottom wall of the second capsule is in contact with the adjustment surface, so that the edge of the first capsule at the periphery moves when the first capsule moves.

[0011] Optionally, the second control element includes: A filling pipe, one end of which is connected to the second capsule and the other end of which is connected to the filling device; An extraction pipe, one end of which is connected to the second capsule and the other end of which is used to communicate with the extraction device; The filling pipeline and the extraction pipeline are both provided with a first control valve to control the opening and closing of the filling pipeline and the extraction pipeline.

[0012] Optionally, the second control element includes: A first control pipe, one end of which is connected to the second capsule, and the other end of which is branched and respectively used to connect to the filling device and the extraction device; The second control valve is arranged in the first control pipeline to control the on-off of the first control pipeline.

[0013] Optionally, the first control element includes: a second control pipe, one end of which is connected to the first sac, and the other end of which is connected to a filling device to fill the first sac with a medium; The third control valve is arranged in the second control pipeline to control the on-off of the control pipeline.

[0014] Optionally, the first capsule and the second capsule are both made of flexible materials, so that when the pressure inside the first capsule and the second capsule changes, the first capsule and the second capsule can be deformed.

[0015] Optionally, the contact surface is provided with a pressure detection device to detect the pressure of the contact surface; When the pressure in the middle of the contact surface is greater than the pressure at the edge, the second control member fills the medium into the second bladder to make the pressure in the middle of the contact surface equal to the pressure at the edge; When the pressure in the middle of the contact surface is less than the pressure at the edge, the second control member extracts the medium in the second bladder to make the pressure in the middle of the contact surface the same as the pressure at the edge.

[0016] Optionally, a limiting member is provided on the side wall of the second capsule body, so that when the second control member fills or extracts a medium into or from the second capsule body, the bottom surface of the second capsule body can drive the first capsule body to move. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic structural diagram of an airbag device according to an embodiment of the present invention; Figure 2 A schematic diagram of the positional relationship between a first bag body and a second bag body of an airbag device according to an embodiment of the present invention; Figure 3 A schematic diagram of the positional relationship between another first bag body and a second bag body of an airbag device according to an embodiment of the present invention; Figure 4A schematic diagram of the positional relationship between another first bag body and a second bag body of an airbag device according to an embodiment of the present invention; Figure 5 is a schematic diagram of the positional relationship between a second control member and a second capsule according to an embodiment of the present invention; Figure 6 This is a schematic structural diagram of a second capsule body provided with a limiting ring in an embodiment of the present invention; Figure 7 It is a schematic diagram of the interface of the first bladder before the second bladder is pressurized according to an embodiment of the present invention; Figure 8 for Figure 7 Schematic diagram of the pressure at the contact surface of two adjacent first capsules in the state; wherein the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first capsules, and x2 represents the contact surface of the other first capsule; the Y-axis represents the pressure value of the contact surface; Fig. 9 A schematic diagram of the pressure at the interface of the first bladder after the second bladder according to the embodiment of the present invention is pressurized; Fig.10 for Fig. 9 Schematic diagram of the pressure at the contact surface of two adjacent first capsules in the state; wherein the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first capsules, and x2 represents the contact surface of the other first capsule; the Y-axis represents the pressure value of the contact surface; Fig.11 This is a schematic diagram of the interface of the first bladder before negative pressure is applied to the second bladder according to an embodiment of the present invention; Fig.12 for Fig.11 Schematic diagram of the pressure at the contact surface of two adjacent first capsules in the state; wherein the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first capsules, and x2 represents the contact surface of the other first capsule; the Y-axis represents the pressure value of the contact surface; Fig.13 A schematic diagram of the pressure at the interface of the first bladder after negative pressure is applied to the second bladder according to an embodiment of the present invention; Fig.14 for Fig.13 Schematic diagram of the pressure at the contact surface of two adjacent first capsules in the state; the X-axis represents the extension direction of the contact surface, x1 represents the contact surface of one of the first capsules, and x2 represents the contact surface of the other first capsule; the Y-axis represents the pressure value of the contact surface.

[0018] Reference numerals: 100, first capsule; 110, contact surface; 120, adjustment surface; 200, second capsule; 300, control assembly; 310, first control member; 311, second control pipeline; 312, third control valve; 320, second control member; 321, filling pipeline; 322, extraction pipeline; 323, first control valve; 324, first control pipeline; 325, second control valve; 400, limit member; 500, wafer; 600, retaining ring. DETAILED DESCRIPTION

[0019] In order to make the purpose, 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 part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0020] The following is combined with Figure 1-14 , the specific implementation modes of the present invention are further described in detail.

[0021] An embodiment of the present invention provides 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 generally includes a plurality of independent airbag partitions, which can respectively control the pressure of different areas, thereby achieving precise control of the material removal rate of different areas on the surface of the wafer 500. However, the contact surface 110 of the airbag partition may cause a change in the grinding rate due to the uneven pressure distribution. In order to improve the problem that the contact surface 110 of the airbag partition may cause a change in the grinding rate due to the uneven pressure distribution, the contact surface 110 effect and the edge effect. Refer to Figure 1 , the airbag device comprises: A plurality of first capsules 100, side walls of two adjacent first capsules 100 are connected, the first capsules 100 have a contact surface 110 and an adjustment surface 120 that are oppositely arranged, and the contact surface 110 is 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 the second capsule 200 drives the edge of the first capsule 100 to move when the second capsule 200 is deformed; The control component 300 includes a first control component 310 and a second control component 320. The first control component 310 is connected to the first capsule 100 to fill the medium into the first capsule 100 to cause the first capsule 100 to deform and the contact surface 110 to fit the wafer 500. The second control component 320 is connected to the second capsule 200 to fill or extract the medium into the second capsule 200 to cause 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 tightly fitted with the wafer 500.

[0022] In some embodiments, there are multiple first capsules 100, and the multiple first capsules 100 together form a circle, wherein the side walls of two adjacent first capsules 100 are connected; therefore, when the medium is filled into the first capsule 100, the first capsule 100 will be deformed. When the first capsule 100 is deformed, the bottom surface of the first capsule 100 contacts the surface of the wafer 500. At this time, the rotation of the grinding head will drive the first capsule 100 to rotate on the surface of the wafer 500, thereby grinding the surface of the wafer 500. In some specific embodiments, the first capsule 100 has a contact surface 110 and an adjustment surface 120, and the contact surface 110 and the adjustment surface 120 are arranged opposite to each other, wherein the contact surface 110 is used to contact the surface of the wafer 500, so as to facilitate the first capsule 100 to grind the surface of the wafer 500. In some more specific embodiments, the upper surface of the first capsule 100 is the adjustment surface 120 , and the lower surface of the first capsule 100 is the contact surface 110 , wherein the contact surface 110 is used to contact the surface of the wafer 500 .

[0023] In some embodiments, a plurality of second capsules 200 are provided, and the second capsules 200 are all provided on the adjustment surface 120, and the second capsules 200 are used to assist the first capsule 100 in deforming. 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 the edges of the two adjacent first capsules 100 are driven to move when the first capsule 100 moves.

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

[0026] In some embodiments, reference Figure 2A second capsule 200 is provided at the edge of each first capsule 100, so that when each second capsule 200 is deformed, it will drive the edge of the corresponding first capsule 100 to move.

[0027] More specifically, after the medium is filled in the first capsule 100, 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 medium is filled into the second capsule 200, and the second capsule 200 is deformed. Since the bottom surface of the second capsule 200 is in contact with the adjustment surface 120, during the deformation process of the second capsule 200, the adjustment surface 120 of the first capsule 100 will be driven to move, thereby driving the contact surface 110 of the first capsule 100 to move, 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 capsule 200 is fixed to the adjustment surface 120 of the first capsule 100 .

[0029] When too much medium is filled in the first capsule 100, the edges of the two adjacent first capsules 100 will be squeezed, so that the pressure of the edge of the contact surface 110 of the first capsule 100 on the surface of the wafer 500 increases. At this time, in order to reduce the pressure on the surface of the wafer 500, the medium in the second capsule 200 can be extracted. At this time, the bottom surface of the second capsule 200 moves in the direction 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 driven away from the surface of the wafer 500, thereby driving the contact surface 110 of the first capsule 100 away from the surface of the wafer 500, so that the edge and the middle of the contact surface 110 have the same pressure on the surface of the wafer 500, which facilitates the grinding process.

[0030] In some embodiments, the bottom surface of the second capsule 200 and the adjustment surface 120 of the first capsule 100 can be fixed by bonding or by integral molding, without limitation herein, and the bottom surface of the second capsule 200 can drive 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 further provided on the grinding head, wherein the control component 300 includes a first control component 310 and a second control component 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 so as to deform the first capsule 100 .

[0033] In some specific embodiments, reference Figure 1 The first control member 310 is tubular, so that the inside of the first control member 310 can transport the medium, and the medium can enter the first capsule 100 through the first control member 310, thereby causing the first capsule 100 to deform.

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

[0035] In some embodiments, reference Figure 1 The second control member 320 is connected to the second capsule 200 and is used to fill the medium into the second capsule 200 or extract the medium, so that the second capsule 200 is deformed.

[0036] In some specific embodiments, the second control member 320 is tubular, so that the interior of the second control member 320 can transport the medium, and 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, and the pressure of the second capsule 200 on the adjustment surface 120 of the first capsule 100 is changed by inflating the second capsule 200 or extracting the gas from the second capsule 200, 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 further includes a retaining ring 600; 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 contacts the wafer 500 , so as to fix the wafer 500 and adjust the pressure of the first bladder 100 .

[0039] In some embodiments, the retaining ring 600 is an annular 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 matching 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 position changes of the wafer 500 through deformation.

[0041] In some embodiments, the retaining ring 600 is integrated with the plurality of first capsules 100 of the grinding head and fixed together under the grinding head. Specifically, the inner wall of the retaining ring 600 contacts the side wall of the first capsule 100, and the bottom wall of the retaining ring 600 contacts the wafer 500 to fix the wafer 500 and adjust the pressure of the first capsule 100.

[0042] During the grinding process, the inner edge of the retaining ring 600 slightly contacts the outer edge of the wafer 500 to form a physical limit to prevent the wafer 500 from moving laterally. At the same time, the retaining ring 600, through the synergistic effect with the first capsule 100, evenly transfers the pressure at the contact point between the first capsule 100 and the side wall of the retaining ring 600 to the edge area of ​​the wafer 500. In addition, when the pressure of each first airbag is adjusted due to process requirements (such as pressurization or decompression of the second airbag), the elastic deformation of the retaining ring 600 can absorb part of the pressure fluctuations to avoid sudden changes in the grinding rate at the edge of the wafer 500. At the same time, the elastic design of the retaining ring 600 allows it to automatically adjust the clamping force when there is a slight difference in the thickness of the wafer 500, avoiding local pressure abnormalities caused by the unevenness of the wafer 500.

[0043] During the grinding process, the first bladder 100 of the grinding head applies main pressure by inflating, directly acting on the surface of the wafer 500. The retaining ring 600 transmits part of the pressure to the edge of the wafer 500, and balances the pressure distribution of the airbag partitions through its own deformation.

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

[0045] In some embodiments, part of the second capsule 200 is arranged on the adjustment surface 120 of the first capsule 100 on the periphery of the plurality of first capsules 100, so that the bottom wall of the second capsule 200 contacts the adjustment surface 120 of the first capsule 100, and the side wall of the second capsule 200 contacts the side wall of the retaining ring 600; part of the second capsule 200 is arranged on the adjustment surface 120, and the bottom surface of the second capsule 200 simultaneously covers the connection between two adjacent second capsules 200; at this time, the second capsule 200 is deformed and contacts the side wall of the retaining ring 600. The second capsule 200 in contact with the wall is deformed, driving the first capsule 100 to move, causing the edge of the contact surface 110 in contact with 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 remaining second capsules 200 are deformed, and at the same time, the contact surface 110 at the contact point of two adjacent first capsules 100 is moved, further adjusting the pressure of the contact surface 110 at the contact point of two adjacent first capsules 100 on the surface of the wafer 500.

[0046] In some embodiments, part of the second capsule 200 is arranged on the adjustment surface 120 of the outer first capsule 100 among the plurality of first capsules 100, so that the bottom wall of the second capsule 200 contacts the adjustment surface 120 of the first capsule 100, and the side wall of the second capsule 200 contacts the side wall of the retaining ring 600; part of the second capsule 200 is arranged on the adjustment surface 120, and the bottom surface of the second capsule 200 covers the edge of the first capsule 100 where it is located, and at the same time, the side walls of the two adjacent second capsules 200 on the two adjacent first capsules 100 fit together; at this time, the second capsule 200 is deformed and contacts the side wall of the retaining ring 600 The second capsule 200 in contact is deformed, driving the first capsule 100 to move, causing the edge of the contact surface 110 in contact with 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 remaining second capsules 200 are deformed, each second capsule 200 drives the edge of the corresponding first capsule 100 to move, and the two connected second capsules 200 simultaneously drive the edge of the corresponding first capsule 100 to move, further adjusting the pressure of the contact surface 110 at the contact point of the two adjacent first capsules 100 on the surface of the wafer 500.

[0047] Reference Figure 5 , the second control element 320 includes: A filling pipe 321, one end of which is connected to the second capsule 200, and the other end of which is used to communicate with the filling device; An extraction pipe 322, one end of which is connected to the second capsule 200, and the other end of which is used to communicate with the extraction device; The filling pipeline 321 and the extraction pipeline 322 are both provided with a first control valve 323 to control the opening and closing of the filling pipeline 321 and the extraction pipeline 322 .

[0048] In some embodiments, one end of the filling pipe 321 is connected to the filling device, so that the medium provided by the filling device enters the second capsule 200 through the filling pipe, thereby adjusting the pressure of the second capsule 200. Specifically in this embodiment, the filling device is selected as an air pump, so that it is convenient to fill the second capsule 200 with gas, thereby adding positive pressure to the inside of the second capsule 200; the extraction device is selected as a vacuum pump, so that it is convenient to extract the gas in the second capsule 200, thereby adding negative pressure to the inside of the second capsule 200.

[0049] In some embodiments, the first control valve 323 on the filling pipe 321 controls the on-off of the filling pipe 321. When the first control valve 323 controls the filling pipe 321 to be opened, the gas in the filling device can enter the second capsule 200 through the filling pipe 321; the first control valve 323 on the extraction pipe 322 controls the on-off of the extraction pipe 322. When the first control valve 323 controls the extraction pipe 322 to be opened, the extraction device can extract the gas in the second capsule 200, thereby adjusting the pressure inside the second capsule 200.

[0050] In some embodiments, when the first control valve 323 on the filling pipeline 321 is opened, the first control valve 323 on the extraction pipeline 322 is closed; when the first control valve 323 on the extraction pipeline 322 is opened, the first control valve 323 on the filling pipeline 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 multiple filling pipes 321 are collected into a main pipe, which is connected to the filling device and cooperates with the first control valve 323 on the filling pipe to realize gas control of each filling pipe; the ends of multiple extraction pipes are collected into another main pipe, which is connected to the extraction device and cooperates with the first control valve 323 on the extraction pipe to realize gas control of 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 further include: A first control pipe 324, one end of which is connected to the second capsule 200, and the other end of which is branched and respectively used to connect to the filling device and the extraction device; The second control valve 325 is disposed in the first control pipeline 324 to control the on-off of the first control pipeline 324 .

[0055] In some embodiments, one end of the first control pipe 324 is connected to the interior of the second capsule 200, and the other end forms two branch pipes, which are respectively connected to the filling device and the extraction device. When the filling device is started, the second capsule 200 is filled with the medium, and when the extraction device is started, the medium in the second capsule 200 is extracted. In some embodiments, the extraction device is closed when the filling device is started, and the filling device is closed when the extraction device is started.

[0056] In some embodiments, the second control valve 325 controls the on-off of the first control pipeline 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 exhaust 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 adjust the rate of pressure change in the second bladder 200 .

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

[0061] In some embodiments, the branch pipelines at the ends of each second control pipeline 311 connected to the filling device are first converged into a main pipeline, and the main pipeline is connected to the filling device so that the branch pipelines are connected to the filling device; the branch pipelines at the ends of each second control pipeline 311 connected to the extraction device are first converged into a main pipeline, and the main pipeline is connected to the extraction device so that the branch pipelines are connected to the extraction device.

[0062] Reference Figure 1 , the first control element 310 includes: A second control pipe 311, one end of which is connected to the first capsule 100, and the other end of which is used to communicate with the filling device to fill the medium into the first capsule 100; The second control pipeline 311 is provided with a third control valve 312 to control the on-off of the second control pipeline 311 .

[0063] In some embodiments, the second control pipe 311 is connected to a filling device, and the filling device fills the first capsule 100 with a medium through the second control pipe 311 to adjust the pressure of the first capsule 100 .

[0064] In some embodiments, the third control valve 312 is a solenoid valve to adjust the on-off of the second control pipeline 311 .

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

[0066] In order to facilitate the deformation of the first capsule 100 and the second capsule 200, the first capsule 100 and the second capsule 200 are both made of flexible materials so that the first capsule 100 and the second capsule 200 can be deformed when the pressure inside the first capsule 100 and the second capsule 200 changes.

[0067] In some embodiments, the method of fixing the valve and the pipeline is prior art and will not be described in detail here.

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

[0069] The contact surface 110 is provided with a pressure detection device to detect the pressure of 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 medium into the second capsule 200 to make the pressure in the middle of the contact surface 110 equal to 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 in the second capsule 200 to make the pressure in the middle of the contact surface 110 the same as the pressure at the edge.

[0070] In some embodiments, the pressure detection device is used to detect the pressure exerted on the contact surface 110, thereby detecting the pressure applied by the contact surface 110 on the surface of the wafer 500, wherein when the pressure in the middle of the contact surface 110 is less than the edge pressure, the middle of the contact surface 110 is in contact with the surface of the wafer 500, and there is a gap between the edge and the surface of the wafer 500; when the pressure in the middle of the contact surface 110 is less than the edge pressure, the edge of the contact surface 110 is squeezed due to excessive filling of the medium in the first capsule 100, thereby increasing the pressure on the surface of the wafer 500.

[0071] In some embodiments, reference Figure 6 In order to enable the bottom surface of the second capsule 200 to drive the movement of the first capsule 100 when the pressure in the second capsule 200 changes, a limiting member 400 may be further arranged around the side wall of the second capsule 200. The limiting member 400 is annular and matches the shape of the second capsule 200. When the pressure in the second capsule 200 changes, the position of the side wall of the second capsule 200 will not change due to the limitation of the limiting member 400. At this time, the bottom surface of the second capsule 200 rises or falls to drive the edge movement of the first capsule 100.

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

[0073] In some embodiments, the first capsule 100 may be in a square, triangle, circle or other different shapes, which are not limited here, and are mainly based on being able to achieve the aforementioned functions.

[0074] In some embodiments, the second capsule 200 can be in a square, triangle, circle or other different shapes, which are not limited here, and are mainly based on being able to achieve the aforementioned functions.

[0075] Specifically, when pressurizing, the valve of the second capsule 200 opens, gas is filled into the second capsule 200, the second capsule 200 expands with positive pressure, and the pressure is accurately transmitted to the surface of the wafer 500 through the contact surface 110 of the first capsule 100, thereby accurately increasing the grinding rate at the contact surface 110; when depressurizing, the valve of the second capsule 200 opens, gas is extracted from the airbag, the negative pressure inside the airbag shrinks, and the contraction force is transmitted to the surface of the wafer 500 through the contact surface 110 of the first capsule 100, thereby accurately reducing the grinding rate at the contact surface 110; in this process, A small part of the pressure of the second capsule 200 is transmitted through the gas inside the first capsule 100, thus generating a pressure buffer, thereby improving the problem of sudden pressure change on the contact surface 110 of the first capsule 100. At the same time, the second capsule 200 is not in direct contact with the wafer 500, but in contact with the contact surface 110 of the first capsule 100. Therefore, it can not only apply positive pressure but also negative pressure. When the second capsule 200 is under negative pressure, the pressure applied by the first capsule 100 is actually reduced at the contact surface 110, thereby reducing the grinding rate of the contact surface 110. This directly solves the problem that the uneven surface of the contact airbag after direct negative pressure is applied and shrinks, which can easily cause the wafer 500 to slip and break.

[0076] Figure 7 A schematic diagram of the state of the contact surface 110 of the first bladder 100 before positive pressure is applied to the second bladder 200. The airbag contact surface 110 is concave due to the separation of the airbag, thereby reducing the pressure and further reducing the grinding rate at the contact surface 110; Figure 8 is a schematic diagram of the pressure at the contact surface 110 of the corresponding first capsule 100, where the pressure creates a fault at the contact surface 110; Fig. 9 Schematic diagram of the state of the contact surface 110 of the first bladder 100 after positive pressure is applied to the second bladder 200. At this time, the depression on the surface of the bladder is flattened, the surface of the bladder is flat, the pressure is uniform, and the grinding rate is uniform. Fig.10 is a schematic diagram of the pressure at the contact surface 110 of the corresponding first capsule 100, where the pressure does not produce a fault at the contact surface 110; Fig.11 A schematic diagram of the state of the contact surface 110 of the first capsule 100 before negative pressure is applied to the second capsule 200. Since the first capsule 100 is subjected to high-intensity positive pressure at this time, a tiny 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; Fig.12 is a schematic diagram of the pressure at the contact surface 110 of the corresponding first capsule 100, where the pressure creates a fault at the contact surface 110; Fig.13Schematic diagram of the state of the contact surface 110 of the first bladder 100 after negative pressure is applied to the second bladder 200. At this time, the protrusions on the surface of the bladder are flattened, the surface of the bladder is flat, the pressure is uniform, and the grinding rate is uniform. Fig.14 Schematic diagram of the pressure at the corresponding contact surface 110 of the first capsule 100 , where the pressure does not cause a fault at the contact surface 110 .

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

[0078] The implementation principle of the airbag device for the grinding head of the present invention is that, when working, air is first inflated into the first capsule 100 to fix the wafer 500 and achieve the target grinding rate at the same time; then, air is inflated or evacuated into the second capsule 200, and the positive pressure generated by the inflation or the negative pressure generated by the evacuation can be accurately transmitted to the surface of the wafer 500 through the contact surface 110 of the first capsule 100, thereby realizing pressurization or decompression at the contact surface 110, and further realizing precise control of the grinding rate at the contact surface 110.

[0079] Although the embodiments of the present invention are described in detail above, it is obvious 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 are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. An airbag device for a grinding head, characterized in that: include: A plurality of first capsules (100), the side walls of two adjacent first capsules (100) being connected, the first capsules (100) having a contact surface (110) and an adjustment surface (120) arranged opposite to each other, the contact surface (110) being used for contacting a wafer (500); A 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) is deformed, the edge of the first capsule (100) is driven to move; The control component (300) comprises a first control component (310) and a second control component (320), wherein the first control component (310) is connected to the first capsule (100) to fill the first capsule (100) with a medium so that the first capsule (100) is deformed, and the contact surface (110) is in contact with the wafer (500); the second control component (320) is connected to the second capsule (200) to fill or extract a medium from the second capsule (200) so that the second capsule (200) is deformed, 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).

2. The airbag device according to claim 1, characterized in that: The bottom wall of the second capsule (200) covers the edges of two adjacent first capsules (100), so that when the first capsule (100) moves, the edges of the two adjacent first capsules (100) are driven to move.

3. The airbag device according to claim 1, characterized in that: Also included is a retaining ring (600); The inner wall of the retaining ring (600) contacts the side wall of the first sac (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 sac (100).

4. The airbag device according to claim 3, characterized in that: The side wall of the second capsule (200) contacts the inner wall of the retaining ring (600) or contacts the side wall 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, the edge of the first capsule (100) at the periphery moves.

5. The airbag device according to claim 1, characterized in that: The second control member (320) comprises: A filling pipe (321), one end of which is connected to the second capsule (200) and the other end of which is used to communicate with a filling device; An extraction pipe (322), one end of which is connected to the second capsule (200) and the other end of which is used to be connected to the extraction device; The filling pipeline (321) and the extraction pipeline (322) are both provided with a first control valve (323) to control the opening and closing of the filling pipeline (321) and the extraction pipeline (322).

6. The airbag device according to claim 1, characterized in that: The second control member (320) comprises: A first control pipe (324), one end of which is connected to the second capsule (200), and the other end of which is branched and respectively used to connect to a filling device and an extraction device; The second control valve (325) is provided on the first control pipeline (324) to control the opening and closing of the first control pipeline (324).

7. The airbag device according to claim 1, characterized in that: The first control member (310) comprises: a second control pipe (311), one end of which is connected to the first sac (100), and the other end of which is used to communicate with a filling device so as to fill the first sac (100) with a medium; The third control valve (312) is provided on the second control pipeline (311) to control the on-off of the control pipeline.

8. The airbag device according to claim 7, characterized in that: The first capsule (100) and the second capsule (200) are both made of flexible materials, so that when the pressure inside the first capsule (100) and the second capsule (200) changes, the first capsule (100) and the second capsule (200) can be deformed.

9. The airbag device according to any one of claims 1 to 8, characterized in that: The contact surface (110) is provided with a pressure detection device to detect the pressure of 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 capsule (200) with a medium so that the pressure in the middle of the contact surface (110) is equal to 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 in the second capsule (200) to make the pressure in the middle of the contact surface (110) the same as the pressure at the edge.

10. The airbag device according to claim 8, characterized in that: The side wall of the second capsule (200) is provided with a limiting member (400) so that when the second control member (320) fills or extracts a medium into or from the second capsule (200), the bottom surface of the second capsule (200) can drive the first capsule (100) to move.

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