Abrasion detection device of grinding head retaining ring and chemical mechanical grinding equipment

Abstract

The utility model provides an abrasion detection device of a grinding head retaining ring and chemical mechanical grinding equipment. The abrasion detection device comprises a liquid flowing hole, a liquid flowing groove, a light beam emitter, a light beam receiver and a controller. At least one protrusion is provided with a liquid flowing hole, and the liquid flowing hole is connected with a liquid supply pipeline of the grinding head so that detection liquid can be conveyed to the liquid flowing hole through the liquid supply pipeline. The liquid flowing groove is formed in the bottom face of the protrusion and communicated with the liquid flowing hole. The light beam emitter and the light beam receiver are respectively arranged in the chemical mechanical polishing equipment, the light beam emitter is used for emitting a plurality of mutually parallel detection light beams, and the light beam receiver is used for receiving the plurality of detection light beams. The controller is in control connection with the light beam emitter, the light beam receiver and the grinding head. The wear detection device is arranged in the chemical mechanical polishing equipment, and can detect the retaining ring in the production process, so that the worn retaining ring can be detected in time, the worn retaining ring can be replaced in time, and the influence on the production quality of subsequent wafers is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a wear detection device for a polishing head retaining ring and a chemical mechanical polishing equipment. Background Art

[0002] The semiconductor industry belongs to a high-precision industry, which puts extremely high requirements on wafer processing equipment. Chemical Mechanical Polishing (CMP), as a planarization process, is widely used in semiconductor manufacturing. The processing mechanism of CMP is mainly to soften the film quality on the wafer surface through chemical reactions, and at the same time use the grinding force of mechanical force to remove surface substances.

[0003] The main function of the retaining ring of the polishing head is to press on the polishing pad with a relatively large pressure, so that the polishing of the wafer can be carried out within the retaining ring, that is, to ensure that the wafer operates within the control range of the polishing head and prevent the wafer from slipping out and causing fragments. Since the function of the retaining ring is to keep the wafer rotating at a high speed within the control range, a relatively high pressure will be applied. Due to the participation of mechanical force, during the processing, the hardware consumables of CMP will have a certain degree of wear with the increase of the polishing time. The most important one is the wear between the retaining ring of the polishing head and the polishing pad. The wear of the retaining ring will cause deformation of the polishing pad, which will in turn affect the polishing effect of the edge part of the wafer. At present, for the detection of the retaining ring, only after the machine is turned off, the retaining ring is detected by an instrument. However, if the retaining ring is worn, it has already affected the product. How to timely detect the wear of the retaining ring during the production process to avoid affecting the subsequent wafer production quality is a technical problem to be solved urgently.

[0004] In view of this, it is necessary to provide a wear detection device for a polishing head retaining ring and a chemical mechanical polishing equipment to solve the above problems. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a wear detection device for a polishing head retaining ring and a chemical mechanical polishing equipment, so as to improve the problem that the wear of the retaining ring cannot be detected in time during the production process.

[0006] The utility model provides a wear detection device for a polishing head retaining ring. A plurality of protrusions are formed at intervals at the bottom of the retaining ring and gaps are formed between adjacent protrusions. The wear detection device includes: a liquid flow hole, a liquid flow groove, a light beam emitter, a light beam receiver and a controller;

[0007] At least one of the protrusions is provided with the liquid flow holes, one end of each liquid flow hole extends to the top surface of the protrusion and the other end extends to the bottom surface of the protrusion, and one end of the liquid flow hole is connected to the liquid supply pipeline of the polishing head to convey the detection liquid into the liquid flow hole through the liquid supply pipeline;

[0008] The liquid flow groove is arranged on the bottom surface of the protrusion and is communicated with the liquid flow hole. One end of the liquid flow groove extends to the inner arc side of the protrusion and the other end extends to the outer arc side of the protrusion;

[0009] The beam emitter and the beam receiver are respectively arranged inside the chemical mechanical polishing equipment. The beam emitter is used for emitting a plurality of parallel detection beams, and the beam receiver is used for receiving the plurality of detection beams;

[0010] The controller is respectively connected to the beam emitter, the beam receiver and the polishing head in a controlled manner. The position and direction of the polishing head are controlled and adjusted through the controller so that the liquid flow hole is located above the detection beam. When the bottom surface of the protrusion is not worn, the detection liquid will vertically drip after flowing out of the liquid flow hole. When the bottom surface of the protrusion is inclined due to wear, the detection liquid will flow along the liquid flow groove towards the inner arc side or the outer arc side of the protrusion after flowing out of the liquid flow hole, causing the dripping position of the detection liquid to deviate from the liquid flow hole. The controller determines whether the protrusion is worn according to the positional relationship between the blocked detection beam and the liquid flow hole.

[0011] The beneficial effect of the wear detection device for the polishing head retaining ring provided by the present utility model is as follows: By arranging the liquid flow holes and the liquid flow grooves on the protrusions of the retaining ring, when the bottom surface of the protrusion is not worn, the detection liquid will vertically drip after flowing out of the liquid flow holes. Once the bottom surface of the protrusion is worn to form a slope, the detection liquid will flow along the slope in the liquid flow groove, resulting in the dripping position of the detection liquid deviating from the liquid flow hole. The position and direction of the polishing head are controlled and adjusted through the controller so that the liquid flow hole is located above the detection beam. When the detection liquid drips downward, it will block the detection beam. The controller can determine whether the protrusion is worn according to the positional relationship between the blocked detection beam and the liquid flow hole. The wear detection device is arranged inside the chemical mechanical polishing equipment, and the retaining ring can be detected during the production process, so that the worn retaining ring can be detected in time and replaced in time to avoid affecting the production quality of the subsequent wafers.

[0012] In a possible embodiment, the controller includes:

[0013] A signal receiving unit, connected to the beam receiver and used for receiving the detection signal of the detection beam sent by the beam receiver;

[0014] A wear detection unit, connected to the signal receiving unit and configured to obtain the occlusion condition of each detection beam according to the detection signal of the detection beam. If the occluded detection beam is the detection beam aligned with the liquid flow hole, it is determined that the protrusion has not worn; if the occluded detection beam is not the detection beam aligned with the liquid flow hole, it is determined that the protrusion has worn.

[0015] Its beneficial effect is that: the cooperative work of the signal receiving unit and the wear detection unit realizes accurate and reliable detection of the wear condition of the retaining ring on the grinding head.

[0016] In a possible embodiment, the controller further includes:

[0017] A slope detection unit, connected to the wear detection unit and configured to, when the wear detection unit determines that the protrusion has worn, obtain the detection time according to the supply start time of the detection liquid to the occlusion time of the detection beam, and look up a pre-established slope detection table according to the detection time to obtain the slope of the bottom surface of the protrusion. The slope detection table includes the corresponding relationship between different slopes of the bottom surface of the protrusion and the detection time.

[0018] Its beneficial effect is that: the slope detection unit can look up a pre-established slope detection table according to the detection time to obtain the slope of the bottom surface of the protrusion, without the need for complex slope calculation, improving the detection efficiency.

[0019] In a possible embodiment, the depth range of the liquid flow groove is 8mm - 12mm. Its beneficial effect is that: by reasonably setting the depth of the liquid flow groove, it is avoided that when the bottom surface of the protrusion wears, the liquid flow groove is also worn away together, making the detection liquid unable to flow along the liquid flow groove.

[0020] In a possible embodiment, the width range of the liquid flow groove is 3mm - 4mm. Its beneficial effect is that: by reasonably setting the width of the liquid flow groove, the detection liquid can flow along the path defined by the liquid flow groove without deviation.

[0021] In a possible embodiment, the liquid flow groove is arranged along the radial direction of the retaining ring. Its beneficial effect is that: the protrusion of the retaining ring usually wears along the radial direction of the retaining ring. By arranging the liquid flow groove along the radial direction of the retaining ring, when the bottom surface of the protrusion wears, the detection liquid will directly flow along the slope direction of the bottom surface of the protrusion.

[0022] In a possible embodiment, the liquid flow hole is arranged vertically. When the bottom surface of the protrusion is not worn, the detection liquid flows straight down along the vertically arranged liquid flow hole without changing the flow path, avoiding the detection liquid deviating from the liquid flow hole after flowing out.

[0023] In a possible embodiment, the wear detection device further includes an alarm connected to the controller. When the controller determines that the protrusion is worn, the controller controls the alarm to give an alarm. The beneficial effect is that when it is detected that the protrusion is worn, the controller controls the alarm to give an alarm to timely remind the operator to take measures.

[0024] In a possible embodiment, there are several protrusions provided with the liquid flow holes on the retaining ring;

[0025] There are several groups of the beam emitters and the beam receivers;

[0026] By adjusting the position and direction of the retaining ring, each protrusion provided with the liquid flow hole can correspond to a group of the beam emitters and the beam receivers.

[0027] The beneficial effect is that by respectively providing the liquid flow holes on several protrusions and synchronously detecting the protrusions provided with the liquid flow holes through several groups of the beam emitters and the beam receivers, the wear conditions of the protrusions in different directions on the retaining ring can be obtained simultaneously, thereby improving the detection efficiency.

[0028] The present invention also provides a chemical mechanical polishing device, including: a wear detection device of a polishing head retaining ring in any of the above embodiments. Description of the Drawings

[0029] Figure 1 It is an improved schematic diagram of the wear detection device of the polishing head retaining ring of the present invention on the retaining ring.

[0030] Figure 2 It is a schematic diagram of the protrusion and the detection beam in the wear detection device of the polishing head retaining ring of the present invention.

[0031] Figure 3 It is a schematic diagram when the detection liquid drops in the wear detection device of the polishing head retaining ring of the present invention.

[0032] Figure 4 It is a schematic diagram of the beam emitter, the beam receiver, the controller and the polishing head in the wear detection device of the polishing head retaining ring of the present invention.

[0033] Figure 5 It is a schematic diagram of the beam receiver, the controller and the alarm in the wear detection device of the polishing head retaining ring of the present invention.

[0034] Description of reference numerals: 100, retaining ring; 110, protrusion; 111, liquid flow hole; 112, liquid flow groove; 120, gap; 210, beam emitter; 220, beam receiver; 230, detection beam; 300, controller; 310, signal receiving unit; 320, wear detection unit; 330, slope detection unit; 400, alarm; 500, detection liquid; 600, polishing head. Detailed implementation manners

[0035] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0036] In view of the problems existing in the prior art, the embodiments of the present utility model provide a wear detection device for a polishing head retaining ring. Refer to Figures 1 to 4 , a plurality of protrusions 110 arranged at intervals and a gap 120 located between two adjacent protrusions 110 are formed at the bottom of the retaining ring 100. The wear detection device includes: a liquid flow hole 111, a liquid flow groove 112, a beam emitter 210, a beam receiver 220 and a controller 300. The liquid flow hole 111 is arranged on at least one protrusion 110. One end of the liquid flow hole 111 extends to the top surface of the protrusion 110 and the other end extends to the bottom surface of the protrusion 110. One end of the liquid flow hole 111 is connected to the liquid supply pipeline of the polishing head 600 to convey the detection liquid 500 into the liquid flow hole 111 through the liquid supply pipeline. The liquid flow groove 112 is arranged on the bottom surface of the protrusion 110 and is communicated with the liquid flow hole 111. One end of the liquid flow groove 112 extends to the inner arc side of the protrusion 110 and the other end extends to the outer arc side of the protrusion 110. The beam emitter 210 and the beam receiver 220 are respectively arranged in the chemical mechanical polishing equipment. The beam emitter 210 is used for emitting a plurality of mutually parallel detection beams 230, and the beam receiver 220 is used for receiving the plurality of detection beams 230. The detection beam 230 can be a visible light beam, an infrared beam or a laser beam, etc.

[0037] The controller 300 is respectively connected to the beam emitter 210, the beam receiver 220, and the polishing head 600 in a controlled manner. The position and orientation of the polishing head 600 are controlled and adjusted through the controller 300, so that the liquid flow hole 111 is located above the detection beam 230. When the bottom surface of the protrusion 110 is not worn, the detection liquid 500 will vertically drip after flowing out of the liquid flow hole 111. When the bottom surface of the protrusion 110 is inclined due to wear, the detection liquid 500 will flow along the liquid flow groove 112 towards the inner arc side or the outer arc side of the protrusion 110 after flowing out of the liquid flow hole 111, causing the dripping position of the detection liquid 500 to deviate from the liquid flow hole 111. The controller 300 determines whether the protrusion 110 is worn according to the positional relationship between the blocked detection beam 230 and the liquid flow hole 111.

[0038] The existing chemical mechanical polishing equipment does not have the function of detecting the wear of the retaining ring 100 of the polishing head 600. The detection of the retaining ring 100 can only be carried out after the machine is taken off. In this embodiment, a wear detection device is provided in the chemical mechanical polishing equipment, which can detect the wear condition of the protrusion 110 of the retaining ring 100. By detecting the retaining ring 100 during the production process, the wear condition of the retaining ring 100 can be found in time, and measures can be taken quickly. For example, the worn retaining ring 100 can be replaced to avoid affecting the production quality of the subsequent wafers. The existing detection of the retaining ring 100 can only be carried out after the machine is stopped. The wear detection device in this embodiment can detect the wear state of the retaining ring 100 without stopping the machine, reducing the interruption time due to shutdown inspection and improving the production efficiency.

[0039] In one embodiment, referring to Figure 5 , the controller 300 includes: a signal receiving unit 310, which is connected to the beam receiver 220 and is used to receive the detection signal of the detection beam 230 sent by the beam receiver 220; a wear detection unit 320, which is connected to the signal receiving unit 310 and is used to obtain the occlusion condition of each detection beam 230 according to the detection signal of the detection beam 230. If the blocked detection beam 230 is the detection beam 230 aligned with the liquid flow hole 111, it is determined that the protrusion 110 is not worn; if the blocked detection beam 230 is not the detection beam 230 aligned with the liquid flow hole 111, it is determined that the protrusion 110 is worn.

[0040] In this embodiment, the signal receiving unit 310 can receive the detection signal of the detection beam 230 and transmit it to the wear detection unit 320. The wear detection unit 320 determines the occlusion situation of each detection beam 230 according to the received detection signal. If the detected beam 230 blocked is the detection beam 230 aligned with the liquid flow hole 111, and the bottom surface of the protrusion 110 has no deformation to generate a slope, and the detection liquid 500 vertically drops onto the detection beam 230 aligned with the liquid flow hole 111 after flowing out of the liquid flow hole 111, it is determined that the protrusion 110 has not worn. If the detected beam 230 blocked is not the detection beam 230 aligned with the liquid flow hole 111, and the bottom surface of the protrusion 110 deforms to generate a slope, the detection liquid 500 will flow along the liquid flow groove 112 towards the inner arc side or the outer arc side of the protrusion 110 after flowing out of the liquid flow hole 111, and the dropping position of the detection liquid 500 is not the detection beam 230 aligned with the liquid flow hole 111, it is determined that the protrusion 110 has worn.

[0041] In a preferred embodiment, referring to Figure 5 , the controller 300 further includes: a slope detection unit 330, connected to the wear detection unit 320 and used to obtain a detection time from the supply start time of the detection liquid 500 to the occlusion time of the detection beam 230 when the wear detection unit 320 determines that the protrusion 110 has worn, and look up a pre-established slope detection table according to the detection time to obtain the slope of the bottom surface of the protrusion 110. The slope detection table includes the corresponding relationship between different slopes of the bottom surface of the protrusion 110 and the detection time.

[0042] The corresponding relationship table between different slopes of the bottom surface of the protrusion 110 and the detection time is obtained by means of simulation experiments in advance. For example, a batch of retaining rings 100 with different slopes of the bottom surface of the protrusion 110 and known slopes of each protrusion 110 are obtained, and simulation experiments are carried out on this batch of retaining rings 100 respectively to obtain the detection time under different slopes of the bottom surface of the protrusion 110, and the corresponding relationship table between different slopes of the bottom surface of the protrusion 110 and the detection time is established. During the actual detection process, according to the actually measured detection time, looking up this corresponding relationship table can obtain the corresponding slope of the bottom surface of the protrusion 110, avoiding the complex slope calculation process. This lookup operation is much faster than real-time calculation, can significantly shorten the detection time, and improve the detection efficiency.

[0043] It should be emphasized that the signal receiving unit 310, the wear detection unit 320, and the slope detection unit 330 in the present invention are all hardware devices provided on the controller 300.

[0044] In a specific embodiment, referring to Figure 1 and Figure 3, the depth range of the liquid flow groove 112 is 8 mm - 12 mm. Since the liquid flow groove 112 is located at the bottom surface of the protrusion 110, when the depth of the liquid flow groove 112 is too shallow, when the bottom surface of the protrusion 110 is worn, the liquid flow groove 112 may also be worn away. Without the flow path defined by the liquid flow groove 112, the detection liquid 500 may flow randomly, thereby affecting the accuracy of the detection. When the depth of the liquid flow groove 112 is too deep, it will reduce the thickness of the protrusion 110 at the position of the liquid flow groove 112. As a result, when subjected to the same external force, this position of the liquid flow groove 112 will become a stress concentration point. Over time, this stress concentration will accelerate the fatigue wear of the protrusion 110 with the liquid flow groove 112 and reduce the service life of the retaining ring 100.

[0045] In another specific embodiment, refer to Figure 1 and Figure 3 , the width range of the liquid flow groove 112 is 3 mm - 4 mm. The design of the liquid flow groove 112 is to guide and restrict the flow path of the detection liquid 500. An overly wide liquid flow groove 112 may cause the detection liquid 500 to disperse during the flow process. By reasonably setting the width of the liquid flow groove 112, the detection liquid 500 can flow along the flow path defined by the liquid flow groove 112 without deviation. In addition, since the liquid flow groove 112 is located at the bottom surface of the protrusion 110, when the width of the liquid flow groove 112 is too wide, the structure at the bottom of the protrusion 110 will become relatively weak, resulting in uneven stress distribution between the bottom of the protrusion 110 and other parts of the protrusion 110. Over time, this uneven stress distribution will accelerate the fatigue wear of the protrusion 110 with the liquid flow groove 112 and reduce the service life of the retaining ring 100.

[0046] In a preferred embodiment, refer to Figure 1 and Figure 3 , the liquid flow groove 112 is arranged along the radial direction of the retaining ring 100. During the use of the retaining ring 100, the bottom surface of its protrusion 110 is usually worn along the radial direction of the retaining ring 100. Setting the liquid flow groove 112 along the radial direction of the retaining ring 100 conforms to the natural trend of the wear of the protrusion 110. After the bottom surface of the protrusion 110 is worn, the detection liquid 500 can flow smoothly directly along this slope direction, making the flow of the detection liquid 500 smoother.

[0047] In a possible embodiment, refer to Figure 3 , the liquid flow hole 111 is arranged vertically. When the bottom surface of the protrusion 110 is not worn, the detection liquid 500 flows straight down along the vertically arranged liquid flow hole 111 without changing the flow path, avoiding the detection liquid 500 deviating from the liquid flow hole 111 after flowing out, thereby improving the accuracy and reliability of the detection.

[0048] In a possible embodiment, refer to Figure 5, the wear detection device further includes an alarm 400 connected to the controller 300. When the controller 300 determines that the protrusion 110 is worn, the controller 300 controls the alarm 400 to give an alarm. By connecting the alarm 400 to the controller 300, the wear detection device can quickly make a judgment through the controller 300 and control the alarm 400 to give an alarm at the moment when it detects that the protrusion 110 is worn. This instant feedback mechanism ensures that the operator can learn about the wear condition of the retaining ring 100 in a timely manner, so that corresponding measures can be taken promptly.

[0049] In one embodiment, there are several protrusions 110 provided with liquid flow holes 111 on the retaining ring 100; there are several groups of beam emitters 210 and beam receivers 220; by adjusting the position and direction of the retaining ring 100, each protrusion 110 provided with a liquid flow hole 111 can correspond to a group of beam emitters 210 and beam receivers 220. In this embodiment, by providing several protrusions 110 provided with liquid flow holes 111 on the retaining ring 100 and equipping corresponding numbers of combinations of beam emitters 210 and beam receivers 220, synchronous detection of these protrusions 110 can be achieved, the wear conditions of multiple protrusions 110 can be obtained simultaneously, and moreover, it is not necessary to detect each protrusion 110 provided with a liquid flow hole 111 one by one, thus greatly improving the detection efficiency and shortening the detection time.

[0050] Furthermore, several protrusions 110 provided with liquid flow holes 111 are evenly spaced along the circumferential direction of the retaining ring 100, and the wear conditions of the protrusions 110 in different directions on the retaining ring 100 can be obtained simultaneously, ensuring comprehensive and uniform detection of the wear condition of the entire retaining ring 100. This circumferential uniform distribution method avoids detection blind spots or repeated detections caused by the over-concentration or sparseness of the positions of the protrusions 110, thus improving the accuracy and reliability of the detection.

[0051] The following explains the wear detection process of the retaining ring protrusion in combination with a specific embodiment.

[0052] When detecting the wear of the protrusion 110 of the retaining ring 100, the controller 300 controls and turns on the beam emitter 210 and the beam receiver 220, and controls and adjusts the position and direction of the grinding head 600 through the controller 300 to make the liquid flow hole 111 located above the detection beam 230.

[0053] The controller 300 starts the liquid supply system to convey the detection liquid 500 to the liquid supply pipeline of the polishing head 600. The beam receiver 220 transmits the detection signal of the detection beam 230 to the signal receiving unit 310 in real time. The signal receiving unit 310 then transmits the detection signal of the detection beam 230 to the wear detection unit 320. The wear detection unit 320 determines the occlusion situation of each detection beam 230 according to the detection signal of the detection beam 230, and based on the positional relationship between the occluded detection beam 230 and the liquid flow hole 111, that is, whether the occluded detection beam 230 is the detection beam 230 aligned with the liquid flow hole 111. If so, the protrusion 110 has not been worn. If not, the protrusion 110 has been worn.

[0054] When the wear detection unit 320 determines that the protrusion 110 has been worn, the controller 300 controls the alarm 400 to issue an alarm. At the same time, the slope detection unit 330 obtains the detection time from the supply start time of the detection liquid 500 to the occlusion time of the detection beam 230, and looks up the pre-established slope detection table according to the detection time to obtain the slope of the bottom surface of the protrusion 110.

[0055] The present utility model also provides a chemical mechanical polishing device, including: the wear detection device of the polishing head retaining ring in any of the above embodiments.

[0056] The technical effects of the wear detection device of the polishing head retaining ring and the chemical mechanical polishing device of the present utility model are explained in detail.

[0057] 1. Compared with the prior art where the detection of the retaining ring 100 can only be carried out after taking the machine off, in the present utility model, the wear detection device is directly arranged in the chemical mechanical polishing device, which means that during the production process, the wear of the protrusion 110 of the retaining ring 100 can be detected without stopping the machine, so as to timely discover the wear situation of the retaining ring 100, and measures can be taken quickly, greatly improving the production efficiency.

[0058] 2. By detecting the dripping detection liquid 500 through the beam emitter 210 and the beam receiver 220, and combined with the intelligent analysis of the controller 300, the wear situation of the protrusion 110 on the retaining ring 100 can be quickly and accurately judged. Further, by using a plurality of groups of beam emitters 210 and beam receivers 220 to respectively detect the detection liquid 500 flowing out of the liquid flow holes 111 of a plurality of protrusions 110, the wear situations of the protrusions 110 in different directions on the retaining ring 100 can be detected simultaneously, thereby improving the comprehensiveness and accuracy of the detection of the overall wear situation of the retaining ring 100.

[0059] 3. The wear detection unit 320 can determine whether the protrusion 110 is worn according to the positional relationship between the blocked detection light beam 230 and the liquid flow hole 111. If the protrusion 110 is worn, the slope detection unit 330 obtains the detection time from the supply start time of the detection liquid 500 to the blocked time of the detection light beam 230, and looks up the pre-established slope detection table according to this detection time, so as to quickly obtain the slope of the bottom surface of the protrusion 110, avoiding the complex slope calculation process and greatly improving the slope detection efficiency.

[0060] 4. By setting reasonable depths and widths of the liquid flow grooves 112 and the path of the liquid flow grooves 112 in the radial direction of the retaining ring 100, it is avoided that the liquid flow grooves 112 are also worn away when the bottom surface of the protrusion 110 is worn, so that the detection liquid 500 can flow along the path defined by the liquid flow grooves 112 without deviation, ensuring the accuracy of detection.

[0061] 5. When it is detected that the protrusion 110 is worn, the controller 300 controls the alarm 400 to give an alarm, so as to timely remind the operator to take measures and timely replace the worn retaining ring 100, avoiding affecting the production quality of subsequent wafers.

[0062] Although the embodiments of the present invention have been described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes are all within the scope and spirit of the present invention described in the claims. Moreover, the present invention described herein may have other embodiments and can be implemented or realized in various ways. Unless otherwise defined, the technical terms or scientific terms used herein should have the ordinary meaning understood by those of ordinary skill in the art to which the present invention belongs.

Claims

1. A wear detection device for a grinding head retaining ring, characterized in that, A plurality of protrusions are formed at intervals on the bottom of the retaining ring, and gaps are formed between adjacent protrusions. The wear detection device includes: a liquid flow hole, a liquid flow groove, a light beam emitter, a light beam receiver, and a controller; The liquid flow hole is provided on at least one of the protrusions. One end of the liquid flow hole extends to the top surface of the protrusion and the other end extends to the bottom surface of the protrusion. One end of the liquid flow hole is connected to the liquid supply pipeline of the polishing head to convey the detection liquid into the liquid flow hole through the liquid supply pipeline; The liquid flow groove is provided on the bottom surface of the protrusion and is communicated with the liquid flow hole. One end of the liquid flow groove extends to the inner arc side of the protrusion and the other end extends to the outer arc side of the protrusion; The light beam emitter and the light beam receiver are respectively arranged in the chemical mechanical polishing equipment. The light beam emitter is used to emit a plurality of parallel detection light beams, and the light beam receiver is used to receive the plurality of detection light beams; The controller is respectively connected to the light beam emitter, the light beam receiver, and the polishing head. The position and direction of the polishing head are controlled and adjusted through the controller so that the liquid flow hole is located above the detection light beam. When the bottom surface of the protrusion is not worn, the detection liquid will vertically drip after flowing out of the liquid flow hole. When the bottom surface of the protrusion is inclined due to wear, the detection liquid will flow along the liquid flow groove towards the inner arc side or the outer arc side of the protrusion after flowing out of the liquid flow hole, causing the dripping position of the detection liquid to deviate from the liquid flow hole. The controller judges whether the protrusion is worn according to the positional relationship between the blocked detection light beam and the liquid flow hole.

2. The wear detection device for the grinding head retaining ring according to claim 1, characterized in that, The controller includes: A signal receiving unit, connected to the light beam receiver and used to receive the detection signal of the detection light beam sent by the light beam receiver; A wear detection unit, connected to the signal receiving unit and used to obtain the occlusion situation of each detection light beam according to the detection signal of the detection light beam. If the blocked detection light beam is the detection light beam aligned with the liquid flow hole, it is judged that the protrusion is not worn; if the blocked detection light beam is not the detection light beam aligned with the liquid flow hole, it is judged that the protrusion is worn.

3. The wear detection device for the grinding head retaining ring according to claim 2, characterized in that, The controller further includes: A slope detection unit, connected to the wear detection unit and used to obtain the detection time according to the start time of the supply of the detection liquid to the occlusion time of the detection light beam when the wear detection unit judges that the protrusion is worn, and to find the slope of the bottom surface of the protrusion by looking up a pre-established slope detection table according to the detection time. The slope detection table includes the corresponding relationship between different slopes of the bottom surface of the protrusion and the detection time.

4. The wear detection device for the grinding head retaining ring according to claim 1, wherein, The depth range of the liquid flow groove is 8 mm - 12 mm.

5. The wear detection device for the grinding head retaining ring according to any one of claims 1-4, characterized in that, The width range of the liquid flow groove is 3 mm - 4 mm.

6. The wear detection device for the grinding head retaining ring according to any one of claims 1-4, characterized in that, The liquid flow groove is arranged along the radial direction of the retaining ring.

7. The wear detection device for the grinding head retaining ring according to any one of claims 1-4, characterized in that, The liquid flow hole is arranged vertically.

8. The wear detection device for the grinding head retaining ring according to any one of claims 1-4, characterized in that, An alarm is further included and is connected to the controller. When the controller judges that the protrusion is worn, the controller controls the alarm to give an alarm.

9. The wear detection device for the grinding head retaining ring according to any one of claims 1-4, characterized in that, The number of protrusions provided with the liquid flow holes on the retaining ring is several; The beam emitter and the beam receiver are provided in several groups; By adjusting the position and orientation of the holding ring, each projection provided with the liquid flow hole can correspond to a group of the beam emitter and the beam receiver.

10. A chemical mechanical polishing apparatus, characterized in that, Comprising: The wear detection device for the grinding head holding ring according to any one of claims 1-9.

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