Polishing head detection device and method, chemical mechanical polishing equipment and computer storage medium

Abstract

The invention discloses a polishing head detection device and method, chemical mechanical polishing equipment and a computer storage medium. The polishing head detection device comprises external image acquisition equipment and an analysis unit, and the external image acquisition equipment is arranged on the outer side of a bearing cup; the external image acquisition equipment is used for at least acquiring a first detection image on the outer side of a retaining ring located on the outer side of the end, close to the bearing cup, of the polishing head when the polishing head and the bearing cup do not bear the wafer; and the analysis unit is used for determining that the connection part is abnormal when the gray value of the connection part corresponding to the metal layer and the non-metal layer in the retaining ring in the first detection image is greater than a preset gray threshold. According to the invention, through the first detection image acquired by the external image acquisition equipment, whether the connection part has the gap can be analyzed based on the first detection image, so that whether the retaining ring is abnormal can be known in time before wafer processing, corresponding processing can be carried out in time, and damage to the wafer and chemical mechanical polishing equipment is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of chemical mechanical polishing, and in particular to a polishing head detection device, method, chemical mechanical polishing equipment and computer storage medium. Background Art

[0002] In the manufacture of integrated circuits / semiconductors (IC), the surface flatness of the wafer is very high, so the wafer surface needs to be polished. Chemical mechanical polishing (CMP) is one of the important process steps in the current semiconductor integrated circuit manufacturing industry. CMP equipment mainly uses a polishing head to adsorb and carry the wafer to the polishing pad, and completes the flattening of the wafer surface under the combined action of mechanical friction and chemical reaction. The polishing head is an important component of the CMP equipment, which is directly related to the effect and efficiency of polishing.

[0003] However, the retaining ring on the polishing head used to fix the wafer position is usually made of a metal part and a plastic part bonded together. During the polishing process, as the polishing time increases, the glue at the bonding position of the metal part and the plastic part on the retaining ring may corrode or fail, eventually causing the plastic part of the retaining ring to fall off, resulting in the CMP equipment shutting down. Summary of the invention

[0004] In view of this, the present application provides a polishing head detection device, method, chemical mechanical polishing equipment and computer storage medium to at least partially solve the above technical problems.

[0005] The first aspect of the present application provides a polishing head detection device, comprising: an external image acquisition device and an analysis unit, wherein the external image acquisition device is arranged on the outside of a carrying cup; the external image acquisition device is used to at least acquire a first detection image of the outside of a retaining ring located on the outside of one end of the polishing head close to the carrying cup when no wafer is carried on the polishing head and the carrying cup; the analysis unit is used to determine that an abnormality occurs in the connection portion when a grayscale value of the connection portion between the metal layer and the non-metallic layer in the retaining ring in the first detection image is greater than a preset grayscale threshold.

[0006] Optionally, the external image acquisition device includes a plurality of first image acquisition units, which are arranged in sequence along the outer side of the retaining ring, each of the first image acquisition units is spaced the same distance from the outer side of the retaining ring, and the plurality of first image acquisition units are of the same height.

[0007] Optionally, the first image acquisition units are spaced apart from each other at the same distance.

[0008] Optionally, the polishing head detection device also includes: an internal image acquisition device, which is arranged on the inner side of the supporting cup, and the internal image acquisition device is arranged on a bracket included in the supporting cup, and the bracket is used to transport the supported wafer to reciprocate along a direction perpendicular to the gripping surface of the polishing head; the internal image acquisition device is used to acquire a second detection image located on the inner side of the retaining ring when the external image acquisition device acquires the first detection image and the elastic membrane inside the polishing head is lifted under the action of negative pressure, wherein the edge of the elastic membrane is connected to the inner side of the retaining ring; the analysis unit is used to determine that an abnormality occurs in the connection portion when the grayscale value of the connection portion between the metal layer and the non-metallic layer in the retaining ring in the second detection image is greater than a preset grayscale threshold.

[0009] Optionally, the internal image acquisition device includes a plurality of second image acquisition units, which are arranged in sequence along the inner side of the retaining ring, each of the second image acquisition units is spaced the same distance from the outer side of the retaining ring, and the plurality of second image acquisition units are of the same height.

[0010] Optionally, the polishing head detection device also includes: an image collection unit; the image collection unit is used to collect the first detection image and / or the second detection image, and send the collection result to the analysis unit; the analysis unit is used to determine that an abnormality has occurred in the connection part when the grayscale value of the connection part between the metal layer and the non-metallic layer in the retaining ring corresponding to the collection result is greater than a preset grayscale threshold.

[0011] Optionally, the polishing head detection device further includes: a flushing unit, which is arranged on the outer edge of the bracket; the flushing unit is used to flush the lens included in the internal image acquisition device and / or the external image acquisition device.

[0012] Optionally, the first image acquisition unit includes: a first camera or a first laser emitter, and a lifting bracket and a fixed platform, the camera or laser emitter is fixedly connected to one end of the lifting bracket, and the other end of the lifting bracket is fixedly connected to the fixed platform; the first camera is used to capture the outside detection image of the outside of the retaining ring frame by frame, wherein the first detection image is obtained based on multiple frames of outside detection images; the first laser emitter is used to emit a laser to the outside of the retaining ring, and capture the outside laser detection image of the laser reflected back from the outside of the retaining ring frame by frame, wherein the first detection image is obtained based on multiple frames of outside laser detection images; the lifting bracket is used to reciprocate in a direction perpendicular to the ground to drive the first camera or the first laser emitter to move, and make the image acquisition range of the first camera or the first laser emitter include the outside of the retaining ring; the fixed platform is used to fix the lifting bracket to fix the first camera or the first laser emitter.

[0013] Optionally, the second image acquisition unit includes: a second camera or a second laser emitter, and a rotating bracket, a rotating shaft and a lifting platform, wherein the second camera or the second laser emitter is fixedly connected to one end of the rotating bracket, and the other end of the rotating bracket is fixedly connected to the lifting platform through the rotating shaft; the second camera is used to capture the inner detection image of the inner side of the retaining ring frame by frame, wherein the second detection image is obtained based on multiple frames of inner detection images; the second laser emitter is used to emit laser to the inner side of the retaining ring, and capture the inner laser detection image of the laser reflected back from the inner side of the retaining ring frame by frame, wherein the second detection image is obtained based on multiple frames of inner laser detection images; the rotating bracket is used to rotate around the rotating shaft to drive the second camera or the second laser emitter to rotate, and make the image acquisition range of the second camera or the second laser emitter include the inner side of the retaining ring; the lifting platform is used to drive the rotating bracket to reciprocate in a direction perpendicular to the ground, so as to drive the second camera or the second laser emitter to reciprocate in a direction perpendicular to the ground, so that the rotating bracket and the second camera or the second laser emitter move toward the direction close to the ground after the detection is completed.

[0014] Optionally, the analysis unit is used to send an alarm signal to a corresponding data receiving end when an abnormality occurs in the connection part, so that the corresponding data receiving end replaces the polishing head with the abnormality in the connection part according to the prompt of the alarm signal.

[0015] A second aspect of the present application provides a polishing head detection method, comprising: when neither the polishing head nor the supporting cup carries a wafer, collecting a first detection image of the outside of a retaining ring located on the outside of one end of the polishing head close to the supporting cup by an external image acquisition device, wherein the external image acquisition device is arranged on the outside of the supporting cup, and the supporting cup is used to carry the wafer to be polished or the wafer after polishing; analyzing the first detection image, and when the grayscale value of the connection portion corresponding to the metal layer and the non-metallic layer in the retaining ring in the first detection image is greater than a preset grayscale threshold, it is determined that the connection portion is abnormal.

[0016] Optionally, the polishing head detection may also include: when the external image acquisition device acquires the first detection image and the elastic membrane inside the polishing head is lifted under the action of negative pressure, the internal image acquisition device acquires a second detection image located on the inner side of the retaining ring, wherein the edge of the elastic membrane is connected to the inner side of the retaining ring; analyzing the second detection image, and when the grayscale value of the connection part between the metal layer and the non-metallic layer in the retaining ring in the second detection image is greater than a preset grayscale threshold, it is determined that the connection part is abnormal.

[0017] The third aspect of the present application provides a polishing system, comprising: a polishing disk, a polishing head, a polishing pad, a liquid supply device, a dresser, a supporting cup and a polishing head detection device as described in the first aspect of the embodiment; the polishing head is used to grab the wafer to be polished on the supporting cup and abut it against the polishing pad above the polishing disk, and place the polished wafer on the supporting cup after polishing; the liquid supply device is used to supply polishing liquid between the polishing pad and the wafer during the polishing process; the dresser is used to dress the surface of the polishing pad; the supporting cup is used to support the wafer to be polished or the polished wafer.

[0018] A fourth aspect of the present application provides a computer storage medium having a computer program stored thereon, which, when executed by a processor, implements the method described in the second aspect of the embodiment.

[0019] In a fifth aspect, the present application provides a computer program product, including computer instructions, which instruct a computing device to perform operations corresponding to the method described in the second aspect of the embodiment.

[0020] The present application uses an external image acquisition device to capture a first detection image of the outside of a retaining ring located on the outside of one end of the polishing head close to the carrying cup when no wafer is carried on the polishing head and the carrying cup. Based on the first detection image, it can be analyzed whether a gap has appeared in the connection part due to corrosion from the polishing liquid or friction damage. Therefore, it can be timely known whether there is any abnormality in the retaining ring before wafer processing, and corresponding processing can be performed in time to avoid damage to the wafer and chemical mechanical polishing equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0022] Figure 1 is a schematic diagram of a polishing head detection device according to an embodiment of the present application; Figure 2 is a cross-sectional view of a retaining ring applicable to an embodiment of the present application; Figure 3 It is a structural schematic diagram of a polishing head detection device according to an embodiment of the present application; Figure 4 It is a schematic diagram of an application scenario of an internal image acquisition device according to an embodiment of the present application; Figure 5 is a schematic diagram of a polishing head detection device according to another embodiment of the present application; Figure 6 is a schematic diagram of a first image acquisition unit according to an embodiment of the present application; Figure 7 is a schematic diagram of a second image acquisition unit according to an embodiment of the present application; Figure 8 is a flowchart of the steps of a polishing head detection method according to an embodiment of the present application; Fig. 9 is a schematic diagram of a polishing system according to an embodiment of the present application; Fig.10 is a schematic diagram of a polishing system according to another embodiment of the present application; Fig.11 is a cross-sectional view of a polishing system according to an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the embodiments of the present application should fall within the scope of protection of the embodiments of the present application.

[0024] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0025] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0026] The technical solutions in the embodiments of the present application are clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In the absence of conflict, the following embodiments and their technical features can be combined with each other.

[0027] Figure 1 FIG. 1 is a schematic diagram of a polishing head detection device according to an embodiment of the present application. Figure 1 As shown, the polishing head detection device 100 includes: an external image acquisition device 101 and an analysis unit 102 , and the external image acquisition device 101 is arranged outside the carrying cup 200 .

[0028] The external image acquisition device 101 is used to acquire at least a first detection image of the outer side of the retaining ring 301 located on the outer side of one end of the polishing head 300 close to the carrying cup 200 when no wafer is carried on the polishing head 300 and the carrying cup 200. The analysis unit 102 is used to determine that an abnormality occurs in the connection portion when the grayscale value of the connection portion between the metal layer and the non-metal layer in the retaining ring 301 in the first detection image is greater than a preset grayscale threshold.

[0029] like Figure 2As shown, the retaining ring 301 is formed by bonding a metal layer and a non-metal layer. When processing the wafer, the retaining ring 301 on the polishing head 300 contacts the polishing pad and applies pressure to it, thereby keeping the wafer on the inner side of the retaining ring 301, i.e., inside the polishing head 300, so that the wafer will not be thrown out during the rotational polishing process. On the other hand, the removal rate of the edge of the wafer can be adjusted by controlling the pressure in the active area of ​​the retaining ring 301. During this process, due to the friction and the invasion of the polishing liquid, the bonding position between the metal layer and the non-metallic layer of the retaining ring 301, that is, the glue at the connection part, will corrode or fail, causing the bonding state of the connection part of the retaining ring 301 to change. Over a long period of time, it will affect the overall flatness of the plastic part of the retaining ring, causing over-polishing or under-polishing of the wafer edge. At the same time, the polishing liquid will continue to penetrate inward through the position where the glue is corroded or failed. Combined with the effect of friction, the eroded part will be further increased, and eventually the non-metallic part of the retaining ring close to the polishing pad will fall off, and under the action of centrifugal force, abnormal pressure will be applied to the wafer or it will fall out and hit other parts, causing damage to the wafer and the chemical mechanical polishing equipment. In order to avoid the occurrence of this phenomenon, it is necessary to monitor the connection between the metal layer and the non-metal layer in the retaining ring 301 before wafer processing. Specifically, an external image acquisition device 101 is arranged on the outside of the carrier cup 200. The external image acquisition device 101 may include at least one image acquisition device, such as a camera, etc. Before wafer processing, that is, when no wafer is carried on the polishing head 300 and the carrier cup 200, at least a first detection image of the outside of the retaining ring 301 located on the outside of one end of the polishing head 300 close to the carrier cup 200 is collected. The first detection image includes The image of the bonding position between the metal layer and the non-metal layer of the retaining ring 301 is encapsulated. After obtaining the first detection image, the analysis unit 102 detects the first detection image. Since the grayscale value of the gap in the connection part is greater than the grayscale value of the metal layer or the non-metal layer in the image, when the grayscale value of the connection part between the metal layer and the non-metal layer in the retaining ring 301 in the first detection image is greater than the preset grayscale threshold, it can be judged that the connection part may have a gap due to corrosion by the polishing liquid or friction damage, and it is determined that the connection part is abnormal.

[0030] Specifically, the analysis unit 102 is used to send an alarm signal to the corresponding data receiving end 400 when an abnormality occurs in the connection part, so that the corresponding data receiving end 400 replaces the polishing head 300 with the abnormality in the connection part according to the prompt of the alarm signal.

[0031] When the analysis unit 102 determines that an abnormality has occurred in the connection part, it will send an alarm signal to the corresponding data receiving end 400. After receiving the alarm signal, the data receiving end 400 will emit a series of short and sharp alarm sounds such as buzzers and sirens, and / or emit bright flashing lights to prompt the staff to replace the polishing head 300 with the abnormality in the connection part, so as to avoid the staff from negligently using the polishing head including the retaining ring with the abnormality in the connection part to process the wafer, thereby further improving the safety of production.

[0032] In the embodiment of the present application, when no wafer is carried on the polishing head 300 and the carrying cup 200, a first detection image of the outside of the retaining ring 301 located on the outside of the end of the polishing head 300 close to the carrying cup 200 is collected by the external image acquisition device 101. Based on the analysis of the first detection image, it can be determined whether there is cracking of the connection portion due to corrosion by the polishing liquid or friction damage, and thus whether there is an abnormality in the retaining ring 301 can be promptly known before wafer processing, so that corresponding processing can be performed in time, thereby avoiding damage to the wafer and the chemical mechanical polishing equipment.

[0033] Figure 3 is a schematic diagram of the structure of a polishing head detection device according to an embodiment of the present application. Figure 3 As shown, the external image acquisition device 101 includes a plurality of first image acquisition units 1011, which are arranged in sequence along the outer side of the retaining ring 301, each first image acquisition unit 1011 has the same spacing with the outer side of the retaining ring 301, and the plurality of first image acquisition units 1011 have the same height.

[0034] In order to better capture the image of the connecting portion of the retaining ring 301, the external image acquisition device 101 may include a plurality of first image acquisition units 1011, for example, including four first image acquisition units 1011, the four first image acquisition units 1011 are of the same height, that is, they are in the same horizontal plane, and each first image acquisition unit 1011 has the same spacing with the outer side of the retaining ring 301, therefore, the four first image acquisition units 1011 are located at four positions on the concentric circles of the retaining ring 301.

[0035] Specifically, the intervals between the first image acquisition units 1011 are the same. For example, the four first image acquisition units 1011 may be arranged at four positions with equal intervals on the concentric circles of the retaining ring 301. At this time, each first image acquisition unit 1011 will capture an image of the connection portion of a quarter of the retaining ring 301 when capturing an image. Therefore, at least three first image acquisition units 1011 may be further arranged to ensure the detection effect of the connection portion of the retaining ring 301.

[0036] By setting the intervals between the first image acquisition units 1011 to be the same, the number of the first image acquisition units 1011 can be reduced to the greatest extent while ensuring that the acquired first detection image can reflect the state of the connection portion of the retaining ring 301 .

[0037] In the embodiment of the present application, since the acquisition range of the first image acquisition unit 1011 is generally a fan-shaped area, a plurality of first image acquisition units 1011 are arranged in sequence along the outer side of the retaining ring 301, and the spacing between each first image acquisition unit 1011 and the outer side of the retaining ring 301 is the same, and the plurality of first image acquisition units 1011 are of the same height, it is possible to ensure as much as possible that the first detection image acquired by the first image acquisition unit 1011 can reflect the state of the connecting portion of the retaining ring 301.

[0038] Figure 4 Schematic diagram of an application scenario of an internal image acquisition device according to an embodiment of the present application. Figure 3-4 As shown, the polishing head detection device 100 also includes: an internal image acquisition device 103, which is arranged on the inner side of the supporting cup 200, and the internal image acquisition device 103 is arranged on the bracket 201 included in the supporting cup 200, and the bracket 201 is used to transport the supported wafer to reciprocate along a direction perpendicular to the gripping surface of the polishing head 300.

[0039] The internal image acquisition device 103 is used to acquire a second detection image located inside the retaining ring 301 when the external image acquisition device 101 acquires the first detection image and the elastic membrane 302 inside the polishing head 300 is lifted under the negative pressure, wherein the edge of the elastic membrane 302 is connected to the inner side of the retaining ring 301. The analysis unit 102 is used to determine that an abnormality occurs in the connection portion when the gray value of the connection portion between the metal layer and the non-metal layer in the retaining ring 301 in the second detection image is greater than a preset gray value threshold.

[0040] Since the external image acquisition device 101 can only capture images of the outside of the retaining ring 301, and the inside of the retaining ring 301 also needs to be inspected, an internal image acquisition device 103 can be set on the bracket 201 inside the carrying cup 200. An elastic membrane 302 is set inside the polishing head 300. When the polishing head 300 needs to grab the wafer, negative pressure will be applied to the elastic membrane 302 to lift the elastic membrane 302. Under the action of atmospheric pressure, negative pressure will be generated between the elastic membrane 302 and the wafer, and the polishing head 300 can complete the grabbing of the wafer. During the inspection process, negative pressure can also be applied to the elastic membrane 302 to lift the elastic membrane 302. At this time, the inside of the retaining ring 301 will not be blocked by the elastic membrane 302, so the internal image acquisition device 103 can capture the second inspection image of the inside of the retaining ring 301. The second detection image includes an image of the bonding position between the metal layer and the non-metal layer on the inner side of the retaining ring 301. After obtaining the second detection image, the analysis unit 102 detects the second detection image. Since the grayscale value of the polishing liquid in the image is greater than the grayscale value of the metal layer or the non-metallic layer in the image, when the grayscale value of the connection between the metal layer and the non-metallic layer in the retaining ring 301 in the second detection image is greater than the preset grayscale threshold, it can be determined that the connection may have a gap due to corrosion by the polishing liquid or friction damage, and it is determined that the connection is abnormal.

[0041] Specifically, the internal image acquisition device 103 includes a plurality of second image acquisition units 1031, which are arranged in sequence along the inner side of the retaining ring 301, each second image acquisition unit 1031 has the same spacing with the outer side of the retaining ring 301, and the plurality of second image acquisition units 1031 have the same height.

[0042] In order to better capture the image of the connecting portion inside the retaining ring 301, the internal image acquisition device 103 may include a plurality of second image acquisition units 1031, for example, including 6 second image acquisition units 1031, the 6 second image acquisition units 1031 are of the same height, that is, they are located in the same horizontal plane, and each second image acquisition unit 1031 is at the same distance from the inner side of the retaining ring 301, therefore, the 6 second image acquisition units 1031 are located at six positions on the concentric circles of the retaining ring 301.

[0043] By setting the intervals between the second image acquisition units 1031 to be the same, the number of the second image acquisition units 1031 can be reduced to the greatest extent while ensuring that the acquired second detection image can reflect the state of the connecting portion inside the retaining ring 301 .

[0044] In the embodiment of the present application, by providing the internal image acquisition device 103 , the inner side of the retaining ring 301 can be inspected, thereby further improving the inspection of the retaining ring 301 .

[0045] Specifically, the polishing head detection device 100 may further include: a flushing unit, which is disposed on the outer edge of the bracket 201. The flushing unit is used to flush the lens included in the internal image acquisition device 103 and / or the external image acquisition device 101.

[0046] Since the lenses included in the internal image acquisition device 103 and the external image acquisition device 101 may be stained, the acquired first detection image and / or the second detection image may be abnormal, affecting the detection of the retaining ring 301, a flushing unit may be provided to flush the lenses included in the internal image acquisition device 103 and the external image acquisition device 101.

[0047] In the embodiment of the present application, by providing a flushing unit, it is possible to ensure that the lenses included in the internal image acquisition device 103 and the external image acquisition device 101 remain clean, so as to further improve the accuracy of the detection of the retaining ring 301.

[0048] Figure 5 is a schematic diagram of a polishing head detection device according to another embodiment of the present application. Figure 5 As shown, the polishing head detection device 100 may further include: an image collection unit 104. The image collection unit 104 is used to collect the first detection image and / or the second detection image, and send the collection result to the analysis unit 102. The analysis unit 102 is used to determine that the connection part is abnormal when the gray value of the connection part between the metal layer and the non-metal layer in the corresponding retaining ring in the collection result is greater than a preset gray value threshold.

[0049] In the embodiment of the present application, by providing the image collection unit 104 , it is possible to share the data processing pressure with the analysis unit 102 , thereby avoiding the analysis unit 102 from performing data reception and data analysis at the same time, thereby improving the efficiency of the detection of the retaining ring 301 .

[0050] Figure 6 is a schematic diagram of a first image acquisition unit according to an embodiment of the present application, such as Figure 6As shown, the first image acquisition unit 1011 includes: a first camera 10111 or a first laser emitter 10112, and a lifting bracket 10113 and a fixed platform 10114. The camera 10111 or the laser emitter 10112 is fixedly connected to one end of the lifting bracket 10113, and the other end of the lifting bracket 10113 is fixedly connected to the fixed platform 10114. The first camera 10111 is used to capture the outer detection image of the outer side of the retaining ring 301 frame by frame, wherein the first detection image is obtained based on multiple frames of outer detection images. The first laser emitter 10112 is used to emit a laser to the outer side of the retaining ring 301, and capture the outer laser detection image reflected back by the laser from the outer side of the retaining ring 301 frame by frame, wherein the first detection image is obtained based on multiple frames of outer laser detection images. The lifting bracket 10113 is used to reciprocate in a direction perpendicular to the ground to drive the first camera 10111 or the first laser emitter 10112 to move, and make the image acquisition range of the first camera 10111 or the first laser emitter 10112 include the outside of the retaining ring 301. The fixing platform 10114 is used to fix the lifting bracket 10113 to fix the first camera 10111 or the first laser emitter 10112.

[0051] In the process of detecting the bonding position of the metal layer and the non-metallic layer of the retaining ring 301, the polishing head 300 is first moved to the corresponding position, and then the lifting bracket 10113 is controlled to move to adjust the first camera 10111 or the first laser emitter 10112 to a suitable detection position, and a first detection image is obtained through the first camera 10111 or the first laser emitter 10112 for analysis by the analysis unit 102.

[0052] It should be noted that the first camera 10111 or the first laser emitter 10112 can be adjusted to a suitable detection position by: determining the position of the connection part through the analysis unit 102 according to the outer laser detection image collected by the first laser emitter 10112 and reflected back through the outer side of the retaining ring, and controlling the lifting bracket 10113 to rise and fall according to the position of the connection part and the position of the first laser emitter 10112, so that the first laser emitter 10112 is located at a suitable detection position and the emitted laser is located at the connection part. Or determining the position of the connection part through the analysis unit 102 according to the outer laser detection image collected by the first camera 10111, and controlling the lifting bracket 10113 to rise and fall according to the position of the connection part and the position of the first camera 10111, so that the first camera 10111 is located at a suitable detection position, and the shooting position of the first camera 10111 is located at the connection part. Alternatively, a laser sensor is provided on the polishing head, and the laser sensor is located above the retaining ring 301 and is fixed in position, and controls the first camera 10111 or the first laser emitter 10112 to rise until the laser sensor is triggered, indicating that the first camera 10111 or the first laser emitter 10112 rises to a suitable detection position.

[0053] In the embodiment of the present application, since the first image acquisition unit 1011 includes a lifting bracket 10113, the position of the first camera 10111 or the first laser emitter 10112 can be adjusted according to actual conditions to ensure that the first detection image obtained can include an image of the bonding position between the metal layer and the non-metallic layer of the retaining ring 301.

[0054] Figure 7 is a schematic diagram of a second image acquisition unit according to an embodiment of the present application, such as Figure 7 The second image acquisition unit 1031 includes: a second camera 10311 or a second laser emitter 10312, and a rotating bracket 10313, a rotating shaft 10314 and a lifting platform 10315. The second camera 10311 or the second laser emitter 10312 is fixedly connected to one end of the rotating bracket 10313, and the other end of the rotating bracket 10313 is fixedly connected to the lifting platform 10315 through the rotating shaft 10314.

[0055] The second camera 10311 is used to capture the inner detection image of the inner side of the retaining ring 301 frame by frame, wherein the second detection image is obtained based on multiple frames of the inner detection image. The second laser emitter 10312 is used to emit a laser to the inner side of the retaining ring 301, and capture the inner laser detection image reflected back by the laser from the inner side of the retaining ring 301 frame by frame, wherein the second detection image is obtained based on multiple frames of the inner laser detection image. The rotating bracket 10313 is used to rotate around the rotating shaft 10314 to drive the second camera 10311 or the second laser emitter 10312 to rotate, and make the image acquisition range of the second camera 10311 or the second laser emitter 10312 include the inner side of the retaining ring 301. The lifting platform 10315 is used to drive the rotating bracket 10313 to reciprocate in a direction perpendicular to the ground, so as to drive the second camera 10311 or the second laser emitter 10312 to reciprocate in a direction perpendicular to the ground, so that the rotating bracket 10313 and the second camera 10311 or the second laser emitter 10312 move toward the ground after the detection is completed.

[0056] In the process of detecting the bonding position of the inner metal layer and the non-metallic layer of the retaining ring 301, the polishing head 300 is first moved to the corresponding position, and then the rotating bracket 10313 is controlled to rotate around the rotating shaft 10314 to adjust the shooting angle of the second camera 10311 or the second laser emitter 10312 to a suitable position, and a second detection image is obtained through the second camera 10311 or the second laser emitter 10312 for analysis by the analysis unit 102.

[0057] It should be noted that the second camera 10311 or the second laser emitter 10312 needs to be adjusted to the same height as the first camera 10111 or the first laser emitter 10112 through the lifting platform 10315. The adjustment method can be that the analysis unit 102 calculates the target height of the second camera 10311 or the second laser emitter 10312 according to the height of the first camera 10111 or the first laser emitter 10112, and controls the lifting platform 10315 to rise and fall according to the target height, so that the second camera 10311 or the second laser emitter 10312 moves to the target height.

[0058] In the embodiment of the present application, since the second image acquisition unit 1031 includes a rotating bracket 10313, the shooting angle of the second camera 10311 or the second laser emitter 10312 can be adjusted according to actual conditions to ensure that the second detection image obtained can include an image of the bonding position between the inner metal layer and the non-metallic layer of the retaining ring 301.

[0059] Figure 8 is a flow chart of the steps of the polishing head detection method according to an embodiment of the present application. Figure 8As shown, the polishing head detection method includes the following steps: Step 501: When no wafer is carried on the polishing head and the carrying cup, a first detection image of the outer side of a retaining ring located on the outer side of one end of the polishing head close to the carrying cup is collected by an external image collection device.

[0060] When there is no wafer on the polishing head and the carrying cup, the position of the external image acquisition device can be adjusted first. The external image acquisition device is arranged on the outside of the carrying cup. The carrying cup is used to carry the wafer to be polished or the wafer after polishing. The adjustment method can be to analyze the position information of the polishing head, determine the target position of the external image acquisition device, and adjust the external image acquisition device to the target position. After that, the camera included in the external image acquisition device starts to focus automatically. After focusing is completed, the first detection image of the outside of the retaining ring located on the outside of the end of the polishing head close to the carrying cup is collected.

[0061] Step 502: Analyze the first detection image. When the grayscale value of the connection portion between the metal layer and the non-metal layer in the retaining ring in the first detection image is greater than a preset grayscale threshold, it is determined that an abnormality occurs in the connection portion.

[0062] After obtaining the first detection image, OpenCV can be used to perform image grayscale processing, and then the grayscale value of the bonding position between the outer metal layer and the non-metallic layer of the retaining ring 301 is extracted and compared with the preset grayscale threshold. If the grayscale value of the connection between the metal layer and the non-metallic layer in the retaining ring corresponding to the first detection image is greater than the preset grayscale threshold, it is determined that there is an abnormality in the connection.

[0063] In an embodiment of the present application, when no wafer is carried on the polishing head and the carrying cup, a first detection image of the outside of the retaining ring located on the outside of the end of the polishing head close to the carrying cup is collected by an external image acquisition device. Based on the first detection image, it can be analyzed whether a gap has appeared in the connection part due to corrosion from the polishing liquid or friction damage, and thus it can be known in time whether there is any abnormality in the retaining ring before wafer processing, so that corresponding processing can be performed in time, thereby avoiding damage to the wafer and the chemical mechanical polishing equipment.

[0064] In a possible implementation, the polishing head detection method may further include: when an external image acquisition device acquires a first detection image and the elastic membrane inside the polishing head is lifted under the action of negative pressure, an internal image acquisition device acquires a second detection image located inside the retaining ring, wherein the edge of the elastic membrane is connected to the inner side of the retaining ring. The second detection image is analyzed, and when the grayscale value of the connection portion between the metal layer and the non-metallic layer in the retaining ring in the second detection image is greater than a preset grayscale threshold, it is determined that an abnormality occurs in the connection portion.

[0065] Since the external image acquisition device can only capture images of the outside of the retaining ring, and the inside of the retaining ring also needs to be inspected, the image of the inside of the retaining ring can be acquired through the internal image acquisition device. An elastic membrane is provided inside the polishing head. When the polishing head needs to grab the wafer, negative pressure is applied to the elastic membrane to lift the elastic membrane. Under the action of atmospheric pressure, negative pressure is generated between the elastic membrane and the wafer, and the polishing head can now grab the wafer. During the inspection process, negative pressure can also be applied to the elastic membrane to lift the elastic membrane. At this time, the inside of the retaining ring will not be blocked by the elastic membrane, so the internal image acquisition device can capture a second inspection image of the inside of the retaining ring. The second detection image includes an image of the bonding position between the metal layer and the non-metallic layer on the inner side of the retaining ring. After obtaining the second detection image, the analysis unit detects the second detection image. Since the grayscale value of the polishing liquid in the image is greater than the grayscale value of the metal layer or the non-metallic layer in the image, when the grayscale value of the connection between the metal layer and the non-metallic layer in the retaining ring in the second detection image is greater than the preset grayscale threshold, it can be judged that the connection may have a gap due to corrosion by the polishing liquid or friction damage, and it is determined that an abnormality has occurred in the connection.

[0066] In the embodiment of the present application, by providing an internal image acquisition device, the bonding position of the metal layer and the non-metal layer on the inner side of the retaining ring can be detected, thereby further improving the detection of the retaining ring.

[0067] Fig. 9 is a schematic diagram of a polishing system according to an embodiment of the present application, Fig.10 is a schematic diagram of a polishing system according to another embodiment of the present application. Fig.11 is a cross-sectional view of a polishing system according to an embodiment of the present application, Figure 9-11 As shown, the polishing system 600 includes: a polishing plate 601, a polishing head 300, a polishing pad 602, a liquid supply device 603, a dresser 604, a carrier cup 200 and the polishing head detection device 100 in the above embodiment.

[0068] The polishing head 300 is used to grab the wafer to be polished on the carrier cup 200 and place it against the polishing pad 602 above the polishing plate 601, and place the polished wafer on the carrier cup 200 after polishing. The liquid supply device 603 is used to supply polishing liquid between the polishing pad 602 and the wafer during the polishing process. The trimmer 604 is used to trim the surface of the polishing pad 602. The carrier cup 200 is used to carry the wafer to be polished or the polished wafer.

[0069] The specific implementation of the polishing head detection device 100 detecting the retaining ring 301 included in the polishing head 300 can refer to the corresponding descriptions in the corresponding steps and units in the above-mentioned polishing head detection method embodiment or the polishing head detection device embodiment, which will not be repeated here. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the above-described equipment and modules can refer to the corresponding process description in the above-mentioned method embodiment, which will not be repeated here.

[0070] In this embodiment, a computer-readable storage medium is provided, which stores instructions for causing a machine to execute the polishing head detection method as described herein. Specifically, a system or device equipped with a storage medium can be provided, on which a software program code for implementing the functions of any of the above embodiments is stored, and a computer (or CPU or MPU) of the system or device reads and executes the program code stored in the storage medium.

[0071] In this case, the program code read from the storage medium itself can implement the functions in the above method embodiments, so the program code and the storage medium storing the program code constitute part of the present application.

[0072] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer via a communication network.

[0073] In this embodiment, a computer program product is provided, including computer instructions, which instruct a computing device to perform operations corresponding to the above method embodiments.

[0074] It should be pointed out that, according to the needs of implementation, the various components / steps described in the embodiments of the present application can be split into more components / steps, or two or more components / steps or partial operations of components / steps can be combined into new components / steps to achieve the purpose of the embodiments of the present application.

[0075] The above-mentioned method according to the embodiment of the present application can be implemented in hardware, firmware, or implemented as software or computer code that can be stored in a recording medium (such as a CD ROM, RAM, floppy disk, hard disk or magneto-optical disk), or implemented as a computer code originally stored in a remote recording medium or a non-temporary machine-readable medium downloaded through a network and to be stored in a local recording medium, so that the method described herein can be stored in such software processing on a recording medium using a general-purpose computer, a dedicated processor or programmable or dedicated hardware (such as an ASIC or FPGA). It can be understood that a computer, a processor, a microprocessor controller or programmable hardware includes a storage component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by a computer, a processor or hardware, the method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the method shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the method shown herein. Although the present application has been shown and described with respect to one or more implementations, those skilled in the art will think of equivalent deformations and modifications based on the reading and understanding of this specification and the accompanying drawings. The present application includes all such modifications and changes and is limited only by the scope of the appended claims. In particular, with respect to the various functions performed by the above-described components, the terms used to describe such components are intended to correspond to any component that performs the specified function of the component (e.g., which is functionally equivalent) (unless otherwise indicated), even if not structurally equivalent to the disclosed structure that performs the function in the exemplary implementation of the present specification shown herein.

[0076] That is, the above description is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of the present application, such as the mutual combination of technical features between the embodiments, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

[0077] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0078] In order to enable any technician in the field to implement and use the application, the application provides the above description. In the above description, various details are listed for the purpose of explanation. It should be understood that those of ordinary skill in the art can recognize that the application can also be implemented without using these specific details. In other embodiments, the well-known process will not be elaborated in detail to avoid unnecessary details that make the description of the application obscure. Therefore, the application is not intended to be limited to the embodiments shown, but is consistent with the widest range of principles and features disclosed in the application.

[0079] It should be noted that, under the premise of no conflict, the various embodiments and / or the technical features in the various embodiments described in this application can be arbitrarily combined with each other, and the technical solution obtained after the combination should also fall within the protection scope of this application.

[0080] It should be understood that the specific examples in the embodiments of the present application are only to help those skilled in the art to better understand the embodiments of the present application, rather than to limit the scope of the embodiments of the present application. Those skilled in the art can make various improvements and modifications based on the above embodiments, and these improvements or modifications all fall within the scope of protection of the present application.

[0081] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A polishing head detection device, characterized in that: include: An external image acquisition device and an analysis unit, wherein the external image acquisition device is arranged outside the carrying cup; The external image acquisition device is used to acquire at least a first detection image of the outer side of the retaining ring located outside one end of the polishing head close to the carrying cup when no wafer is carried on the polishing head and the carrying cup; The analysis unit is used to determine that an abnormality occurs in the connection portion when a grayscale value of the connection portion between the metal layer and the non-metal layer in the retaining ring in the first detection image is greater than a preset grayscale threshold.

2. The device according to claim 1, characterized in that The external image acquisition device includes a plurality of first image acquisition units, which are arranged in sequence along the outer side of the retaining ring, each of the first image acquisition units has the same distance from the outer side of the retaining ring, and the plurality of first image acquisition units have the same height.

3. The device according to claim 2, characterized in that The first image acquisition units are spaced at the same distance from each other.

4. The device according to claim 2, characterized in that The device further comprises: an internal image acquisition device, the internal image acquisition device is arranged inside the carrying cup, and the internal image acquisition device is arranged on a bracket included in the carrying cup, the bracket is used to transport the carried wafer to reciprocate in a direction perpendicular to the gripping surface of the polishing head; The internal image acquisition device is used to acquire a second detection image located on the inner side of the retaining ring when the external image acquisition device acquires the first detection image and the elastic membrane inside the polishing head is lifted under the negative pressure, wherein the edge of the elastic membrane is connected to the inner side of the retaining ring; The analysis unit is used to determine that an abnormality occurs in the connection portion when a grayscale value of the connection portion between the metal layer and the non-metal layer in the retaining ring in the second detection image is greater than a preset grayscale threshold.

5. The device according to claim 4, characterized in that The internal image acquisition device includes a plurality of second image acquisition units, which are arranged in sequence along the inner side of the retaining ring, each of the second image acquisition units has the same spacing with the outer side of the retaining ring, and the plurality of second image acquisition units have the same height.

6. The device according to claim 4, characterized in that The device further comprises: an image collection unit; The image collection unit is used to collect the first detection image and / or the second detection image, and send the collection result to the analysis unit; The analysis unit is used to determine that an abnormality occurs in the connection portion when a grayscale value of the connection portion between the metal layer and the non-metal layer in the retaining ring corresponding to the collected result is greater than a preset grayscale threshold.

7. The device according to claim 4, characterized in that The device further comprises: a flushing unit, the flushing unit being arranged on the outer edge of the bracket; The flushing unit is used to flush the lens included in the internal image acquisition device and / or the external image acquisition device.

8. The device according to claim 2, characterized in that The first image acquisition unit includes: a first camera or a first laser emitter, and a lifting bracket and a fixed platform, the camera or the laser emitter is fixedly connected to one end of the lifting bracket, and the other end of the lifting bracket is fixedly connected to the fixed platform; The first camera is used to collect the outer detection image of the outer side of the retaining ring frame by frame, wherein the first detection image is obtained based on multiple frames of outer detection images; The first laser emitter is used to emit a laser toward the outside of the retaining ring, and collect an outer laser detection image frame by frame of the laser reflected back from the outer side of the retaining ring, wherein the first detection image is obtained based on multiple frames of outer laser detection images; The lifting bracket is used to reciprocate in a direction perpendicular to the ground to drive the first camera or the first laser emitter to move, and make the image acquisition range of the first camera or the first laser emitter include the outside of the retaining ring; The fixed platform is used to fix the lifting bracket to fix the first camera or the first laser emitter.

9. The device according to claim 5, characterized in that The second image acquisition unit includes: a second camera or a second laser emitter, and includes a rotating bracket, a rotating shaft and a lifting platform, the second camera or the second laser emitter is fixedly connected to one end of the rotating bracket, and the other end of the rotating bracket is fixedly connected to the lifting platform through the rotating shaft; The second camera is used to collect the inner detection image of the inner side of the retaining ring frame by frame, wherein the second detection image is obtained based on multiple frames of inner detection images; The second laser emitter is used to emit a laser toward the inner side of the retaining ring, and collect the inner laser detection image of the laser reflected back from the inner side of the retaining ring frame by frame, wherein the second detection image is obtained based on multiple frames of inner laser detection images; The rotating bracket is used to rotate around the rotating shaft to drive the second camera or the second laser emitter to rotate, and make the image acquisition range of the second camera or the second laser emitter include the inner side of the retaining ring; The lifting platform is used to drive the rotating bracket to reciprocate in a direction perpendicular to the ground, so as to drive the second camera or the second laser emitter to reciprocate in a direction perpendicular to the ground, so that the rotating bracket and the second camera or the second laser emitter move toward the ground after the detection is completed.

10. The device according to claim 1, characterized in that The analysis unit is used to send an alarm signal to the corresponding data receiving end when the connection part is abnormal, so that the corresponding data receiving end can replace the polishing head with the abnormal connection part according to the alarm signal.

11. A polishing head detection method, characterized in that: include: When no wafer is carried on the polishing head and the carrying cup, a first detection image of the outer side of a retaining ring located on the outer side of one end of the polishing head close to the carrying cup is collected by an external image acquisition device, wherein the external image acquisition device is arranged on the outer side of the carrying cup, and the carrying cup is used to carry the wafer to be polished or the polished wafer; The first detection image is analyzed, and when a grayscale value of a connection portion between a metal layer and a non-metal layer in the retaining ring in the first detection image is greater than a preset grayscale threshold, it is determined that an abnormality occurs in the connection portion.

12. The method according to claim 11, characterized in that The method further comprises: When the external image acquisition device acquires the first detection image and the elastic membrane inside the polishing head is lifted under the negative pressure, the internal image acquisition device acquires a second detection image located inside the retaining ring, wherein the edge of the elastic membrane is connected to the inner side of the retaining ring; The second detection image is analyzed, and when a grayscale value of a connection portion between a metal layer and a non-metal layer in the retaining ring in the second detection image is greater than a preset grayscale threshold, it is determined that an abnormality occurs in the connection portion.

13. A polishing system, characterized in that: include: A polishing disc, a polishing head, a polishing pad, a liquid supply device, a dresser, a carrying cup, and a polishing head detection device as described in any one of claims 1 to 10; The polishing head is used to grab the wafer to be polished on the carrying cup and place it against the polishing pad above the polishing plate, and place the polished wafer on the carrying cup after polishing; The liquid supply device is used to supply polishing liquid between the polishing pad and the wafer during the polishing process; The dresser is used to dress the surface of the polishing pad; The carrying cup is used to carry the wafer to be polished or the wafer after polishing.

14. A computer storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the method according to any one of claims 11 to 12 is implemented.

15. A computer program product, characterized in that The method comprises computer instructions, wherein the computer instructions instruct a computing device to execute operations corresponding to the method according to any one of claims 11 to 12.

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