Uniformity detection device for polishing head flexible membrane, cmp apparatus and detection method

Abstract

The application provides a device for detecting uniformity of a flexible film of a polishing head, a CMP equipment and a detection method, comprising: a light beam emitter arranged in the CMP equipment and capable of displacement adjustment in the vertical direction; a light beam detection member arranged in the CMP equipment and used for detecting the light beam emitted by the light beam emitter; during detection, the polishing head performs rotational movement, the light beam emitter emits horizontal light beams to ring sub-zones of the flexible film after pressure is applied, and the uniformity of the flexible film is judged according to the light beam detection condition of the light beam detection member, wherein the flexible film is divided into a plurality of ring sub-zones in the radial direction of the flexible film and in the shape of a ring. In the present application, if the light beam detection member detects intermittent light beams during one rotation of the polishing head, it is judged that the uniformity of the flexible film is abnormal. By arranging the light beam emitter and the light beam detection member in the CMP equipment, the flexible film can be detected in time during the process, and the flexible film with problems can be found in time and measures can be taken.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a uniformity testing device, CMP equipment, and testing method for a flexible film with a grinding head. Background Technology

[0002] The semiconductor industry is a high-precision industry, placing extremely high demands on wafer processing equipment. Chemical Mechanical Polishing (CMP), as a planarization process, is widely used in semiconductor manufacturing. Its main purpose is to maintain the uniformity of wafer thickness after polishing. The working principle of a CMP machine is to use a polishing head that holds the wafer through an internal flexible film. During polishing, corresponding pressure is applied to various zones above the polishing head, pressing the wafer onto a polishing pad for polishing. The zone pressure is a key factor determining the flatness of the polished surface. Currently, a common problem in the industry is that if there are deviations in the manufacturing process of the flexible film on the polishing head, resulting in poor local thickness uniformity of the film, the applied local pressure to the wafer may be insufficient or excessive, leading to wafer contour deviations after polishing.

[0003] The actual effect of partition pressure is the expansion of the flexible film. However, the current method for assessing the uniformity of the flexible film is usually to measure its thickness. This method requires removing the flexible film from the machine, making it impossible to detect the flexible film in a timely and effective manner during the process. If a problematic flexible film continues to undergo chemical mechanical polishing, it will affect the uniformity and quality of wafer polishing, thereby reducing product yield.

[0004] In view of this, it is necessary to propose a uniformity testing device, CMP equipment and testing method for the flexible membrane of the grinding head to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a uniformity testing device, CMP equipment, and testing method for flexible films with grinding heads, so as to improve the problem that existing methods cannot detect flexible films in a timely and effective manner during the process.

[0006] This invention provides a device for detecting the uniformity of a flexible membrane in a grinding head, comprising: A beam emitter is located within a chemical mechanical polishing apparatus and is capable of vertical displacement adjustment; A beam detection device is disposed within the chemical mechanical polishing apparatus and is used to detect the beam emitted by the beam emitter. During detection, the polishing head rotates, and the beam emitter emits a horizontal beam into the annular partitions of the pressurized flexible membrane. Based on the beam detection results of the beam detection device, the uniformity of the flexible membrane is determined. The flexible membrane is divided into several annular partitions in a ring shape along the radial direction of the flexible membrane.

[0007] The beneficial effect of the uniformity detection device for flexible films in the polishing head provided by this invention is that, since the annular partition is ring-shaped, the beam emitted by the beam emitter can detect one ring of the annular partition through the rotation of the polishing head. If the beam detection device detects an intermittent beam during one rotation of the polishing head, it is determined that the uniformity of the flexible film is abnormal. By setting the beam emitter and the beam detection device in the chemical mechanical polishing equipment, the flexible film can be detected in a timely and effective manner during the process, so as to promptly identify problematic flexible films and take measures to avoid affecting subsequent wafer polishing.

[0008] In one possible embodiment, the uniformity detection device further includes a lifting adjustment component vertically disposed within the chemical mechanical polishing apparatus, the beam emitter being horizontally disposed at the top of the lifting adjustment component, and the lifting adjustment component being extendable and adjustable and used to drive the beam emitter to adjust its displacement in the vertical direction.

[0009] Its beneficial effects are as follows: by adjusting the length of the lifting adjustment component, the distance between the flexible film and the beam emitter can be finely and gradually adjusted, so that the beam emitted by the beam emitter can gradually approach the surface of the pressurized annular partition. Through the rotational movement of the grinding head, the beam detects a circumference of the surface of the annular partition. When the beam detection device detects an intermittent beam, the surface of the deformed annular partition is uneven around the circumference, that is, the height is inconsistent. Thus, it can be determined that the uniformity of the flexible film is abnormal.

[0010] In one possible embodiment, the chemical mechanical polishing apparatus is provided with a support platform, which serves as the position for adsorbing and placing the polishing head on the wafer. The support platform is hollow inside and has an open top. The lifting and adjusting assembly is located on the bottom wall of the support platform. After the lifting and adjusting assembly is retracted, the lifting and adjusting assembly and the beam emitter are located inside the support platform.

[0011] Its advantages are as follows: the support platform is hollow inside and open at the top. The lifting and adjusting component is located inside the support platform. When no testing is required, the lifting and adjusting component can be retracted, allowing both the lifting and adjusting component and the beam emitter to be stored inside the support platform without affecting its original function. When testing is required, the lifting and adjusting component can be extended to allow the beam emitter to extend, enabling it to work with the beam detection device to complete uniformity testing.

[0012] In one possible embodiment, the beam detection element is an image acquisition element or a surface beam receiver.

[0013] In one possible embodiment, when the beam detection element is an image acquisition element, the uniformity detection device further includes: An image recognition module is connected to the image acquisition element and is used to perform image recognition on the detection image acquired by the image acquisition element in order to identify whether a beam of light exists in the detection image; The first judgment module is connected to the image recognition module and is used to analyze and process the recognition results of the image recognition module to determine the uniformity of the flexible film.

[0014] Its beneficial effects are as follows: by using an image acquisition element, an image recognition module, and a first judgment module, the uniformity of the flexible membrane can be automatically determined through image recognition and data analysis.

[0015] In one possible embodiment, for the case where the beam detection element is a surface beam receiver, the uniformity detection device further includes: A signal processing module is connected to the planar beam receiver and is used to process the signals received from the planar beam receiver; The second judgment module is connected to the signal processing module and is used to analyze and process the signal processing results of the signal processing module to determine the uniformity of the flexible membrane.

[0016] Its beneficial effects are as follows: by using a surface beam receiver, a signal processing module, and a second judgment module, the uniformity of the flexible film can be automatically determined through signal processing and data analysis.

[0017] In one possible embodiment, the uniformity detection device further includes a protective pad disposed on the top surface of the beam emitter, the protective pad being elastic.

[0018] Its beneficial effect is that by setting the protective pad on the beam emitter, wear on the flexible membrane can be avoided due to contact between the beam emitter and the flexible membrane.

[0019] The present invention also provides a CMP apparatus, comprising: a bearing stage, a grinding head, and a uniformity detection device for the flexible membrane of the grinding head as described in any of the above embodiments.

[0020] The present invention also provides a method for detecting the uniformity of a flexible film with a grinding head, employing a grinding head and a uniformity detection device for the flexible film with a grinding head as described in any of the above embodiments. The uniformity detection method includes: Move and adjust the grinding head so that the center of the grinding head is collinear with the center of the lifting and adjusting assembly; Each of the annular sections of the flexible membrane is pressurized and its uniformity is tested. During the uniformity test, the distance between the flexible membrane and the beam emitter is gradually increased or decreased according to a set step distance and a set step interval time, so that the beam emitted by the beam emitter can gradually approach the surface of the annular section. At each set step interval time, the grinding head is controlled to rotate, and the beam emitter emits a horizontal beam. The beam detection device detects the beam. If the beam detection device detects an intermittent beam during one revolution of the grinding head, the uniformity of the flexible membrane is determined to be abnormal.

[0021] The beneficial effect of the uniformity detection method for flexible films using a grinding head provided by this invention is as follows: the grinding head is placed directly above the lifting adjustment assembly, which is located at the center of the flexible film. During the rotation of the grinding head, a horizontal beam emitted by a beam emitter is used to detect a circumference of the annular partition. If the surface of the annular partition is not uniform, the beam detection element will not be able to continuously receive the beam during rotation, thus indicating an abnormality in the uniformity of the flexible film.

[0022] In one possible embodiment, controlling the spacing between the flexible membrane and the beam emitter to gradually increase or decrease according to a set step distance and a set step interval time includes: Initially, the flexible membrane is close to the beam emitter, and the beam detection device can detect the beam emitted by the beam emitter. The device controls the beam emitter to move closer to the flexible membrane according to a set step distance and a set step interval, thereby gradually reducing the distance between the flexible membrane and the beam emitter; or... In the initial state, the beam emitter is in contact with the flexible membrane, and the beam detection device does not detect the beam emitted by the beam emitter. The beam emitter is controlled to move away from the flexible membrane according to a set step distance and a set step interval time, so as to gradually increase the distance between the flexible membrane and the beam emitter.

[0023] Its beneficial effects are as follows: the beam emitter can be displaced and adjusted in the vertical direction. It can be moved gradually towards the flexible membrane so that the beam emitted by the beam emitter can gradually approach the surface of the annular partition; or, it can be moved gradually away from the flexible membrane so that the beam emitted by the beam emitter can gradually approach the surface of the annular partition. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the installation of the uniformity detection device for the flexible membrane of the grinding head according to the present invention.

[0025] Figure 2 This is a schematic diagram illustrating the uniformity detection device for the flexible membrane of the grinding head according to the present invention, which detects different ring partitions and ensures good uniformity of the different ring partitions.

[0026] Figure 3 This is a schematic diagram illustrating the detection of uniformity anomalies in different ring zones using the uniformity detection device for the flexible membrane of the grinding head according to the present invention.

[0027] Figure 4 This is a schematic diagram of the lifting adjustment component, beam emitter, and protective pad in the uniformity detection device for the flexible membrane of the grinding head of the present invention.

[0028] Figure 5 This is a logic block diagram of one embodiment of the uniformity detection device for the flexible membrane of the grinding head of the present invention.

[0029] Figure 6 This is a logic block diagram of another embodiment of the uniformity detection device for the flexible membrane of the grinding head of the present invention.

[0030] Figure 7 This is a flowchart of the uniformity detection method for the flexible membrane of the grinding head according to the present invention.

[0031] Explanation of reference numerals in the attached drawings: 110, beam emitter; 120, beam detection component; 130, lifting and adjusting assembly; 141, image acquisition element; 142, surface beam receiver; 150, image recognition module; 161, first judgment module; 171, first alarm; 180, signal processing module; 162, second judgment module; 172, second alarm; 190, protective pad; 200, support platform; 300, grinding head; 400, flexible membrane; 410, annular partition. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0033] To address the problems existing in the prior art, embodiments of the present invention provide a device for detecting the uniformity of a flexible membrane in a grinding head. Figure 1 This is a schematic diagram of the installation of the uniformity detection device for the flexible membrane of the grinding head according to the present invention. Figure 2 This is a schematic diagram illustrating the uniformity detection device for the flexible membrane of the grinding head according to the present invention, which detects different ring sections with good uniformity. Figure 3 This is a schematic diagram illustrating the detection of uniformity anomalies in different annular zones using the uniformity detection device for the flexible membrane of the grinding head according to the present invention. (See attached diagram.) Figure 1 , Figure 2 as well as Figure 3 The uniformity testing device includes a beam emitter 110 and a beam detection element 120. The beam emitter 110 is disposed within a chemical mechanical polishing (CMP) apparatus and is vertically adjustable. The beam detection element 120 is disposed within the CMP apparatus and is used to detect the beam emitted by the beam emitter 110. During testing, the polishing head 300 rotates, and the beam emitter 110 emits a horizontal beam into the annular partitions 410 of the pressurized flexible membrane 400. Based on the beam detection results of the beam detection element 120, the uniformity of the flexible membrane 400 is determined. The flexible membrane 400 is divided into several annular partitions 410 in a ring shape along the radial direction of the flexible membrane 400.

[0034] The beam emitter 110 and beam detection component 120 are directly installed inside the chemical mechanical polishing (CMP) equipment. Uniformity testing can be integrated into the production process, allowing for real-time monitoring of the flexible film 400 during operation without requiring disassembly and inspection during downtime. This enables timely detection of problems with the flexible film 400 and timely intervention, preventing defective films from continuing to participate in CMP and causing wafer polishing quality issues. Furthermore, it improves the convenience and efficiency of testing, avoiding production disruptions caused by frequent downtime for inspection.

[0035] The flexible membrane 400 is divided into multiple annular regions, and the beam emitter 110 can perform independent detection on each annular region 410. During the rotation of the polishing head 300, the beam emitter 110 emits a beam around the circumference of the annular region 410. The rotation of the polishing head 300 provides a continuous and stable "scanning path" for the beam emitter 110, enabling comprehensive detection of the entire circumferential region of the flexible membrane 400 and ensuring the comprehensiveness and accuracy of the detection results. During one rotation of the polishing head 300, the beam detection element 120 detects intermittent beams. Intermittent beams can be understood as sometimes being detected (the beam is not blocked by the annular region 410) and sometimes not being detected (the beam is blocked by the annular region 410). If the uniformity of the annular region 410 is good, inconsistent beam blocking will not occur. Therefore, by observing intermittent beams, an abnormality in the uniformity of the flexible membrane 400 can be determined.

[0036] In actual chemical mechanical polishing (CMP) processes, the flexible membrane 400 expands and deforms under applied pressure. Current methods for measuring the thickness of the flexible membrane 400 are performed under non-pressurized conditions, failing to consider its deformation under pressure and thus unable to simulate the actual conditions in CMP processes. Therefore, the measurement results may not accurately reflect the performance of the flexible membrane 400 in the actual process. In this solution, the flexible membrane 400 does not need to be removed from the polishing head 300. Pressure can be applied to cause the annular section 410 to expand and deform, simulating the actual conditions in CMP processes. Therefore, this solution can more accurately detect the deformation of the annular section 410 after pressure application. Consequently, the obtained uniformity assessment results for the flexible membrane 400 will be more accurate and better reflect the actual process conditions.

[0037] See Figure 2 The beam emitter 110 is located at the center of the flexible membrane 400. When the uniformity of the annular partition 410 is good, the deformation of different regions on the annular partition 410 is consistent, and the beam detector 120 will not detect the discontinuous beam.

[0038] See Figure 3 The beam emitter 110 is located at the center of the flexible membrane 400. When the uniformity of the annular partition 410 is abnormal, the regional variables of some parts of the annular partition 410 are too large or too small, such as... Figure 3 In the middle, the deformation on the left side of the ring partition 410 is greater than that on the right side. This causes the beam emitted by the beam emitter 110 to be blocked when it hits the bottom of the side with greater deformation. However, when the beam hits the side with less deformation during this rotation, the beam will not be blocked. In other words, the beam detector 120 will detect the intermittent beam.

[0039] In one embodiment, Figure 4This is a schematic diagram of the lifting adjustment component, beam emitter, and protective pad in the uniformity detection device for the flexible film of the grinding head of the present invention. See also... Figure 4 The uniformity testing device also includes a lifting adjustment assembly 130 vertically installed within the chemical mechanical polishing equipment. A beam emitter 110 is horizontally positioned at the top of the lifting adjustment assembly 130. The lifting adjustment assembly 130 is telescopically adjustable and used to drive the beam emitter 110 to adjust its vertical displacement. The lifting adjustment assembly 130 can be a cylinder, hydraulic cylinder, or electric telescopic rod, etc.

[0040] In this embodiment, the distance between the flexible membrane 400 and the beam emitter 110 can be adjusted by extending and retracting the length of the lifting adjustment component 130. When performing uniformity detection on the annular partition 410, the flexible membrane 400 and the beam emitter 110 are gradually brought closer or further apart. By adjusting the lifting adjustment component 130, the beam emitted by the beam emitter 110 can gradually approach the surface of the pressurized annular partition 410. If the surface of the annular partition 410 is not uniform, that is, the surface of the deformed annular partition 410 is not on the same horizontal plane, and since the beam emitter 110 emits a horizontal beam, during the rotation of the grinding head 300, some areas of the surface of the annular partition 410 will block the beam, while other areas will not block the beam. This will cause the beam detection component 120 to detect the intermittent beam, thereby determining that the uniformity of the flexible membrane 400 is abnormal.

[0041] In one embodiment, see Figure 1 The chemical mechanical polishing (CMP) equipment includes a support platform 200, which serves as the location for the polishing head 300 to adsorb and place the wafer. The support platform 200 is hollow inside and open at the top, with support pillars along its edges to support the wafer. A lifting adjustment assembly 130 is located on the bottom wall of the support platform 200. When the lifting adjustment assembly 130 is retracted, it and the beam emitter 110 are located inside the support platform 200.

[0042] In this embodiment, since the support platform 200 is hollow inside and open at the top, the lifting adjustment component 130 can be placed inside the support platform 200. When uniformity testing is not required, the lifting adjustment component 130 and the beam emitter 110 are housed inside the support platform 200 by shrinking the length of the lifting adjustment component 130. That is, the height of the beam emitter 110 is lower than the height of the support column located at the edge of the support platform 200, so as to avoid obstructing the grinding head 300 from adsorbing and placing the wafer on the support platform 200. The support column can still support the wafer normally, so the normal operation process of the wafer will not be affected by adding the lifting adjustment component 130 and the beam emitter 110. When uniformity testing is required, the lifting adjustment component 130 is stretched so that the beam emitter 110 extends out of the support platform 200, which can cooperate with the beam detection component 120 to realize the uniformity testing of the flexible film 400.

[0043] In some embodiments, Figure 5 This is a logic block diagram of one embodiment of the uniformity detection device for the flexible membrane of the grinding head according to the present invention. Figure 6 Here is a logic block diagram of the uniformity detection device for the flexible membrane of the grinding head according to another embodiment of the present invention. See also: Figure 5 and Figure 6 The beam detection element 120 is either an image acquisition element 141 or a surface beam receiver 142. During detection, by moving the polishing head 300, the beam detection element 120 is positioned outside and close to the polishing head 300. The beam detection element 120 can detect the flexible film 400. The lifting adjustment assembly 130 adjusts its extension and retraction to place the beam emitter 110 within the detection range of the beam detection element 120.

[0044] Image acquisition element 141 is an image sensor, camera, etc. During the detection process, image acquisition element 141 acquires the detection image containing flexible film 400 in real time, and determines the occlusion of the light beam by the ring partition 410 of flexible film 400 based on whether the detection image contains a light beam.

[0045] The surface beam receiver 142 has a receiving area for receiving the beam. The receiving area is surface-shaped. Since the lifting adjustment component 130 needs to be extended and retracted during the detection process, the surface-shaped receiving area is set to ensure that the beam emitter 110 can always be within the detection range of the receiving area during the movement of the beam emitter 110, thus avoiding detection errors caused by the beam deviating from the receiving area.

[0046] In one embodiment, see Figure 5 For the case where the beam detection element 120 is an image acquisition element 141, the uniformity detection device further includes: The image recognition module 150 is connected to the image acquisition element 141 and is used to perform image recognition on the detection image acquired by the image acquisition element 141 to identify whether there is a beam of light in the detection image; The first judgment module 161 is connected to the image recognition module 150 and is used to analyze and process the recognition results of the image recognition module 150 to determine the uniformity of the flexible film 400.

[0047] In this embodiment, the image recognition module 150 accurately identifies the presence of a light beam in the acquired detection image by analyzing the image. The image recognition module 150 identifies the light beam situation in the detection image acquired by the image acquisition element 141 during one rotation of the grinding head 300. In the aforementioned scheme, the light beam detection element 120 detects intermittent light beams. In this scheme, it can be understood that some detection images acquired during this rotation contain light beams, while others do not. Therefore, it can be determined that the uniformity of the flexible membrane 400 is abnormal. This scheme achieves automation and intelligence in detection through the image acquisition element 141, the image recognition module 150, and the first judgment module 161. It can automatically acquire and analyze image data to determine the uniformity of the flexible membrane 400 without manual intervention, avoiding errors from human judgment and improving detection efficiency and accuracy.

[0048] In one specific embodiment, see Figure 5 The uniformity detection device also includes a first alarm 171 connected to the first judgment module 161. The first alarm 171 is used to trigger an alarm when the first judgment module 161 determines that the uniformity of the flexible film 400 is abnormal. This instant feedback mechanism ensures that the operator can quickly know the test results and take timely countermeasures to prevent the problematic flexible film 400 from continuing to participate in chemical mechanical polishing and causing wafer polishing quality problems.

[0049] In one specific embodiment, see Figure 5 The first judgment module 161 is also connected to the grinding head 300 and the lifting adjustment assembly 130. The first judgment module 161 analyzes and processes the recognition results of the image recognition module 150 to determine the uniformity of the flexible film 400, including: During the uniformity testing process, the uniformity testing device performs uniformity testing on each annular section 410 of the flexible membrane 400 one by one and obtains the uniformity testing results of the annular section 410, specifically including: If there is at least one anomaly in the uniformity of the ring partition 410, then the uniformity of the flexible membrane 400 is abnormal. If the uniformity of all annular partitions 410 is normal, based on the changes in beam obstruction during the detection of each annular partition 410, the displacement data of the grinding head 300, and the extension and retraction length data of the lifting adjustment component 130, the surface height of each annular partition 410 under the same pressure is determined one by one. If the deviation between the surface heights of each annular partition 410 is within the set range, it can be understood that the deformation degree of each annular partition 410 is the same under the same pressure, and the uniformity of the flexible membrane 400 is normal; otherwise, the uniformity of the flexible membrane 400 is abnormal.

[0050] In another embodiment, see Figure 6 For the case where the beam detection element 120 is a surface beam receiver 142, the uniformity detection device further includes: The signal processing module 180 is connected to the surface beam receiver 142 and is used to process the signals received from the surface beam receiver 142; The second judgment module 162 is connected to the signal processing module 180 and is used to analyze and process the signal processing results of the signal processing module 180 to judge the uniformity of the flexible membrane 400.

[0051] In this embodiment, when the beam is blocked by the ring partition 410, the surface beam receiver 142 will not be able to receive the beam. When the beam is not blocked by the ring partition 410, the surface beam receiver 142 will receive the beam. The surface beam receiver 142 sends an electrical signal indicating the beam reception status to the signal processing module 180 in real time. The signal processing module 180 can determine the current beam blocking status, i.e., whether the beam is blocked or not at the current moment, by processing and analyzing the real-time received signal. In the aforementioned scheme, the beam detection element 120 detects an intermittent beam. In this scheme, it can be understood that within one rotation, the signal processing module 180 analyzes and finds that the beam is blocked at some moments and not blocked at other moments. Therefore, it can be determined that the uniformity of the flexible film 400 is abnormal. In this scheme, the detection is automated and intelligent through the surface beam receiver 142, the signal processing module 180 and the second judgment module 162. It can automatically collect and analyze image data, and then judge the uniformity of the flexible film 400 without human intervention, thus avoiding errors caused by human judgment and improving detection efficiency and accuracy.

[0052] In one specific embodiment, see Figure 6The uniformity detection device also includes a second alarm 172 connected to the second judgment module 162. The second alarm 172 is used to trigger an alarm when the second judgment module 162 determines that the uniformity of the flexible film 400 is abnormal. This instant feedback mechanism ensures that the operator can quickly know the test results and take timely countermeasures to prevent the problematic flexible film 400 from continuing to participate in chemical mechanical polishing and causing wafer polishing quality problems.

[0053] In one specific embodiment, see Figure 6 The second judgment module 162 is also connected to the grinding head 300 and the lifting adjustment assembly 130. The second judgment module 162 analyzes the signal processing results of the signal processing module 180 to determine the uniformity of the flexible membrane 400, including: During the uniformity testing process, the uniformity testing device performs uniformity testing on each annular section 410 of the flexible membrane 400 one by one and obtains the uniformity testing results of the annular section 410, specifically including: If there is at least one anomaly in the uniformity of the ring partition 410, then the uniformity of the flexible membrane 400 is abnormal. If the uniformity of all annular partitions 410 is normal, based on the changes in beam obstruction during the detection of each annular partition 410, the displacement data of the grinding head 300, and the extension and retraction length data of the lifting adjustment component 130, the surface height of each annular partition 410 under the same pressure is determined one by one. If the deviation between the surface heights of each annular partition 410 is within the set range, it can be understood that the deformation degree of each annular partition 410 is the same under the same pressure, and the uniformity of the flexible membrane 400 is normal; otherwise, the uniformity of the flexible membrane 400 is abnormal.

[0054] In one specific embodiment, see Figure 4 The uniformity detection device also includes a protective pad 190 disposed on the top surface of the beam emitter 110. The protective pad 190 is elastic and is made of elastic materials such as rubber and silicone.

[0055] In this embodiment, by providing a protective pad 190 on the beam emitter 110, the force between the beam emitter 110 and the flexible membrane 400 during contact can be buffered, ensuring a gentler contact between the beam emitter 110 and the flexible membrane 400 and avoiding wear on the flexible membrane 400.

[0056] In some embodiments, the beam emitter 110 is a visible light beam emitter, an infrared beam emitter, or a laser emitter, etc.

[0057] The present invention also provides a CMP device, including: a support stage 200, a grinding head 300, and a uniformity detection device for the flexible film of the grinding head as in any of the above embodiments.

[0058] This invention also provides a method for detecting the uniformity of a flexible membrane in a grinding head. Figure 7 The flowchart of the uniformity detection method for the flexible membrane of the grinding head of the present invention is shown below. Figure 7 The uniformity detection method employs a grinding head 300 and a uniformity detection device for the flexible membrane of the grinding head as described in any of the above embodiments, and includes: S510: Move and adjust the grinding head 300 so that the center of the grinding head 300 is collinear with the center of the lifting adjustment component 130; S520: Pressurize each annular section 410 of the flexible membrane 400 one by one and perform uniformity detection on each annular section 410. When performing uniformity detection on each annular section 410, control the distance between the flexible membrane 400 and the beam emitter 110 to gradually increase or decrease according to the set step distance and set step interval time, so that the beam emitted by the beam emitter 110 can gradually approach the surface of the annular section 410. At each set step interval time, control the polishing head 300 to rotate, and at the same time, the beam emitter 110 emits a horizontal beam. The beam detection element 120 detects the beam. If the beam detection element 120 detects an intermittent beam during one rotation of the polishing head 300, it is determined that the uniformity of the flexible membrane 400 is abnormal.

[0059] In this embodiment, the grinding head 300 is moved so that its center is collinear with the center of the lifting adjustment component 130, i.e., the lifting adjustment component 130 is located at the center of the flexible membrane 400. When the grinding head 300 rotates, the annular partition 410 rotates one revolution, and the beam emitter 110 emits a horizontal beam of light, which can detect the circumference of the annular partition 410. If the surface of the annular partition 410 after pressure is not uniform, i.e., the surface of the annular partition 410 after pressure is not on the same horizontal plane, the beam detection component 120 will not be able to continuously detect the beam during the rotation of the grinding head 300. Thus, it can be determined that the uniformity of the flexible membrane 400 is abnormal.

[0060] In one specific embodiment, the lifting adjustment component 130 in the above embodiment is used to adjust the distance between the flexible membrane 400 and the beam emitter 110.

[0061] In some embodiments, controlling the spacing between the flexible membrane 400 and the beam emitter 110 to gradually increase or decrease according to a set step distance and a set step interval time includes: Initially, the flexible membrane 400 is close to the beam emitter 110. The beam detection unit 120 can detect the beam emitted by the beam emitter 110 and controls the beam emitter 110 to move closer to the flexible membrane 400 according to a set step distance and a set step interval time, so as to gradually reduce the distance between the flexible membrane 400 and the beam emitter 110; or, In the initial state, the beam emitter 110 is in contact with the flexible membrane 400, and the beam detection unit 120 does not detect the beam emitted by the beam emitter 110. The beam emitter 110 is controlled to move away from the flexible membrane 400 according to the set step distance and the set step interval time, so as to gradually increase the distance between the flexible membrane 400 and the beam emitter 110.

[0062] This embodiment provides two specific spacing adjustment methods, which are explained below: One spacing adjustment method is as follows: In the initial state, the beam detection element 120 can detect the beam emitted by the beam emitter 110, meaning the beam is not blocked by the pressurized and expanded annular partition 410, and the flexible film 400 is close to the beam emitter 110, meaning the distance between the flexible film 400 and the beam emitter 110 is close, which can reduce the number of step adjustments and improve detection efficiency. By extending the length of the lifting adjustment component 130, the beam emitter 110 is gradually moved closer to the flexible film 400, so that the beam emitted by the beam emitter 110 can gradually approach the surface of the pressurized annular partition 410. During one revolution of the polishing head 300, if the beam detection element 120 does not detect any beam, it indicates that the uniformity of the annular partition 410 is good. If the beam detection element 120 detects intermittent beams, it indicates that the uniformity of the annular partition 410 is abnormal, and the regional variation of the annular partition 410 is too large or insufficient.

[0063] Another spacing adjustment method is as follows: In the initial state, the beam emitter 110 is in contact with the flexible membrane 400, and the beam detector 120 does not detect the beam emitted by the beam emitter 110, that is, the beam is blocked by the pressurized and expanded annular partition 410. By shortening the length of the lifting adjustment component 130, the beam emitter 110 is gradually moved away from the flexible membrane 400, so that the beam emitted by the beam emitter 110 can gradually approach the surface of the pressurized annular partition 410. During the rotation of the polishing head 300 after the beam detector 120 just detects the beam, if the beam detector 120 detects the beam continuously, it indicates that the uniformity of the annular partition 410 is good. If the beam detector 120 detects the beam intermittently, it indicates that the uniformity of the annular partition 410 is abnormal, and the partial deformation of the annular partition 410 is too large or insufficient.

[0064] In one specific embodiment, the pressure applied to the ring section 410 ranges from 2 psi to 4 psi.

[0065] The technical effects of the uniformity testing device, CMP equipment, and testing method for the grinding head flexible membrane of the present invention will be explained in detail.

[0066] 1. Existing methods for evaluating the uniformity of flexible film 400 involve thickness measurement, which requires removing the flexible film 400 from the machine. This is not only cumbersome but also prevents timely and effective detection of the flexible film 400 during the process. In contrast, the uniformity detection device of this invention directly detects the flexible film 400 inside the chemical mechanical polishing equipment using a beam emitter 110 and a beam detection element 120, eliminating the need to remove the flexible film 400 and enabling detection during the process.

[0067] 2. In the prior art, the uniformity of the flexible membrane 400 is measured by measuring its thickness. This measurement is performed without pressure. However, in the actual chemical mechanical polishing process, the flexible membrane 400 needs to be expanded and deformed by applying pressure. This solution can detect the annular zone 410 that expands and deforms after pressure, which is more in line with the actual process conditions. Therefore, the detection results are more accurate.

[0068] 3. By accurately detecting the uniformity of the flexible film 400 in real time, problematic flexible films 400 can be identified promptly, and corresponding measures can be taken to replace them with new ones. This avoids uneven wafer grinding and grinding quality issues caused by the non-uniformity of the flexible film 400. This not only improves the uniformity and quality of wafer grinding but also reduces the wafer scrap rate due to poor grinding, thereby improving the overall product yield.

[0069] 4. The rotational motion of the grinding head 300 enables the beam emitted by the beam emitter 110 to scan along the circumference of the annular partition 410, thereby achieving comprehensive detection of the surface of the annular partition 410.

[0070] 5. The lifting adjustment component 130 can gradually adjust the distance between the flexible membrane 400 and the beam emitter 110 according to a set step distance and a set step interval time. This precise adjustment method allows the beam to gradually approach the surface of the pressurized annular partition 410, thereby more accurately judging the uniformity of the flexible membrane 400.

[0071] 6. The lifting adjustment assembly 130 and the beam emitter 110 are located within the support platform 200, eliminating the need for additional space within the chemical mechanical polishing equipment. When not in use, the lifting adjustment assembly 130 and the beam emitter 110 can be retracted into the support platform 200 without affecting its original function.

[0072] 7. Either the image acquisition element 141 or the surface beam receiver 142 can be selected as the beam detection element 120. The image acquisition element 141 determines the uniformity of the flexible film 400 through image recognition and data analysis, while the surface beam receiver 142 determines the uniformity of the flexible film 400 through signal processing and data analysis. Automatic detection and judgment improve the efficiency and accuracy of detection.

[0073] 8. The protective pad 190 provided on the top surface of the beam emitter 110 is elastic and can effectively prevent wear caused when the beam emitter 110 comes into direct contact with the flexible membrane 400.

[0074] In the description of this invention, it should be understood that the terms “comprising” and “having” as used herein, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0075] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0076] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0077] 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. Unless otherwise defined, the technical or scientific terms used herein should be understood in their ordinary sense by one of ordinary skill in the art to which this invention pertains.

Claims

1. A device for detecting the uniformity of a flexible membrane in a grinding head, characterized in that, include: A beam emitter is located within a chemical mechanical polishing apparatus and is capable of vertical displacement adjustment; A beam detection device is disposed within the chemical mechanical polishing apparatus and is used to detect the beam emitted by the beam emitter. During detection, the polishing head rotates, and the beam emitter emits a horizontal beam into the annular partitions of the pressurized flexible membrane. Based on the beam detection results of the beam detection device, the uniformity of the flexible membrane is determined. The flexible membrane is divided into several annular partitions in a ring shape along the radial direction of the flexible membrane.

2. The uniformity detection device for the flexible membrane of the grinding head according to claim 1, characterized in that, It also includes a lifting adjustment assembly vertically disposed within the chemical mechanical polishing equipment, with the beam emitter horizontally disposed at the top of the lifting adjustment assembly. The lifting adjustment assembly is telescopically adjustable and used to drive the beam emitter to adjust its displacement in the vertical direction.

3. The uniformity detection device for the flexible membrane of the grinding head according to claim 2, characterized in that, The chemical mechanical polishing equipment is equipped with a support platform, which serves as the position for adsorbing and placing the polishing head on the wafer. The support platform is hollow inside and has an open top. The lifting and adjusting assembly is located on the bottom wall of the support platform. After the lifting and adjusting assembly is retracted, the lifting and adjusting assembly and the beam emitter are located inside the support platform.

4. The uniformity detection device for the flexible membrane of the grinding head according to claim 1, characterized in that, The beam detection element is an image acquisition element or a surface beam receiver.

5. The uniformity detection device for the flexible membrane of the grinding head according to claim 4, characterized in that, For cases where the beam detection element is an image acquisition element, the uniformity detection device further includes: An image recognition module is connected to the image acquisition element and is used to perform image recognition on the detection image acquired by the image acquisition element in order to identify whether a beam of light exists in the detection image; The first judgment module is connected to the image recognition module and is used to analyze and process the recognition results of the image recognition module to determine the uniformity of the flexible film.

6. The uniformity detection device for the flexible membrane of the grinding head according to claim 4, characterized in that, For cases where the beam detection element is a surface beam receiver, the uniformity detection device further includes: A signal processing module is connected to the planar beam receiver and is used to process the signals received from the planar beam receiver; The second judgment module is connected to the signal processing module and is used to analyze and process the signal processing results of the signal processing module to determine the uniformity of the flexible membrane.

7. The uniformity detection device for the flexible membrane of the grinding head according to any one of claims 2-6, characterized in that, It also includes a protective pad disposed on the top surface of the beam emitter, the protective pad being elastic.

8. A CMP device, characterized in that, include: A support platform, a grinding head, and a device for detecting the uniformity of the flexible membrane of the grinding head as described in any one of claims 1-7.

9. A method for detecting the uniformity of a flexible membrane in a grinding head, characterized in that, The uniformity detection method employs a grinding head and a uniformity detection device for a flexible membrane made with the grinding head as described in any one of claims 1-7, the uniformity detection method comprising: Move and adjust the grinding head so that the center of the grinding head is collinear with the center of the lifting and adjusting assembly; Each of the annular sections of the flexible membrane is pressurized and its uniformity is tested. During the uniformity test, the distance between the flexible membrane and the beam emitter is gradually increased or decreased according to a set step distance and a set step interval time, so that the beam emitted by the beam emitter can gradually approach the surface of the annular section. At each set step interval time, the grinding head is controlled to rotate, and the beam emitter emits a horizontal beam. The beam detection device detects the beam. If the beam detection device detects an intermittent beam during one revolution of the grinding head, the uniformity of the flexible membrane is determined to be abnormal.

10. The method for detecting the uniformity of the flexible membrane of the grinding head according to claim 9, characterized in that, The spacing between the flexible membrane and the beam emitter is gradually increased or decreased according to a set step distance and a set step interval time, including: Initially, the flexible membrane is close to the beam emitter, and the beam detection device can detect the beam emitted by the beam emitter. The device controls the beam emitter to move closer to the flexible membrane according to a set step distance and a set step interval, thereby gradually reducing the distance between the flexible membrane and the beam emitter; or... In the initial state, the beam emitter is in contact with the flexible membrane, and the beam detection device does not detect the beam emitted by the beam emitter. The beam emitter is controlled to move away from the flexible membrane according to a set step distance and a set step interval time, so as to gradually increase the distance between the flexible membrane and the beam emitter.

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