Chemical mechanical polishing control method, chemical mechanical polishing apparatus, and electronic device

Abstract

The application provides a chemical mechanical polishing control method, a chemical mechanical polishing device and an electronic device. The method is used for chemical mechanical polishing of a wafer, the wafer comprising a first film and a second film, the first film covering the second film, and the method comprising: obtaining polishing pressure information applied by a polishing head to a plurality of historical wafers before a current wafer; obtaining first thickness information of the first film of the current wafer before chemical mechanical polishing; obtaining second thickness information of the second film of the plurality of historical wafers after chemical mechanical polishing; determining target polishing pressure information for the current wafer according to each polishing pressure information, the first thickness information and each second thickness information; and controlling the polishing head of the chemical mechanical polishing device to apply pressure to the current wafer according to the target polishing pressure information, so as to perform chemical mechanical polishing on the current wafer.

Description

Technical Field

[0001] This application relates to the field of chemical mechanical polishing technology, and in particular to a chemical mechanical polishing control method, chemical mechanical polishing equipment, and electronic equipment. Background Technology

[0002] Current chemical mechanical polishing (CMP) equipment, when performing CMP on wafers containing multilayer thin films, requires a polishing head to apply pressure to the wafer, pressing it onto a polishing pad on a polishing disk. The polishing pad then grinds and removes one layer of the thin film on the wafer. In these technologies, the polishing head uses the same polishing parameters for each wafer. However, when polishing multiple wafers, significant thickness differences can lead to poor thickness uniformity and large variations after CMP, thus reducing the effectiveness of CMP on multiple wafers. Therefore, a technical solution is needed to address this issue. Summary of the Invention

[0003] This application provides a chemical mechanical polishing control method, chemical mechanical polishing equipment, and electronic equipment to at least partially solve the above-mentioned problems.

[0004] According to a first aspect of this application, a chemical mechanical polishing (CMP) control method is provided for chemically mechanically polishing a wafer, the wafer comprising a first thin film and a second thin film, the first thin film covering the second thin film, the method comprising:

[0005] Obtain polishing pressure information from the polishing head applied during chemical mechanical polishing of multiple historical wafers preceding the current wafer;

[0006] Obtain the first thickness information of the first thin film of the current wafer before chemical mechanical polishing;

[0007] Obtain the second thickness information of the second thin film remaining after chemical mechanical polishing of the plurality of historical wafers;

[0008] Based on the polishing pressure information, the first thickness information, and the second thickness information, the target polishing pressure information for the current wafer is determined;

[0009] Based on the target polishing pressure information, the polishing head of the chemical mechanical polishing equipment is controlled to apply pressure to the current wafer in order to perform chemical mechanical polishing on the current wafer.

[0010] According to a second aspect of this application, a chemical mechanical polishing (CMP) apparatus is provided for chemically mechanically polishing a wafer, the wafer including a first thin film and a second thin film, the first thin film covering the second thin film, the CMP apparatus including a polishing head, a polishing disk, and a control device, wherein: the control device is configured to: acquire polishing pressure information applied by the polishing head to a plurality of historical wafers preceding the current wafer during CMP; acquire second thickness information of the second thin film remaining after CMP of the plurality of historical wafers; determine target polishing pressure information for the current wafer based on the polishing pressure information, the first thickness information, and the second thickness information; and control the polishing head to apply pressure to the current wafer to perform CMP on the current wafer based on the target polishing pressure information.

[0011] According to a third aspect of this application, an electronic device is provided, characterized in that it includes: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; the memory is used to store a computer program; and the processor is used to execute the method described in the first aspect by running the computer program stored in the memory.

[0012] According to a fourth aspect of this application, a computer storage medium is provided that stores a computer program thereon, which, when executed by a processor, implements the method described in the first aspect above.

[0013] According to a fifth aspect of this application, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the method described in the first aspect above.

[0014] The chemical mechanical polishing (CMP) control scheme provided in this application combines the polishing pressure information of previous historical wafers, the first thickness information of the first thin film before CMP polishing of the current wafer, and the second thickness information of the remaining second thin film after CMP polishing of the historical wafers, and determines the target polishing pressure information for the current wafer after comprehensive consideration. Therefore, it achieves adaptive adjustment of polishing pressure for different wafers. By controlling the polishing head of the CMP equipment to apply pressure to the current wafer through such polishing pressure information, the thickness uniformity of the current wafer after CMP polishing and the historical wafers can be effectively improved, and the thickness variation of the wafer can be reduced, thereby effectively improving the CMP effect. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0016] Figure 1 This is a flowchart illustrating the steps of an exemplary chemical mechanical polishing control method in this application.

[0017] Figure 2 This is a schematic diagram of an exemplary first and second thin film in this application.

[0018] Figure 3 This is a structural block diagram of an exemplary chemical mechanical polishing apparatus according to this application.

[0019] Figure 4 This is a structural block diagram of an exemplary electronic device according to this application.

[0020] Figure 5 This is a structural block diagram of an exemplary chemical mechanical polishing control device according to this application. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art should fall within the scope of protection of this application. It should be understood that the various steps described in the method implementation of this disclosure can be performed in different orders and / or in parallel. In addition, the method implementation may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect.

[0022] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc., mentioned in this application are used only to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies. It should be noted that the modifications "a" and "a plurality" mentioned in this application are illustrative rather than restrictive, and those skilled in the art should understand that, unless explicitly stated in the context, they should be understood as "one or more".

[0023] The specific implementation of this application will be further explained below with reference to the accompanying drawings.

[0024] According to a first aspect of this application, a chemical mechanical polishing control method is provided. Figure 1 This is a flowchart illustrating an exemplary chemical mechanical polishing (CMP) control method according to this application. The CMP control method is used to perform CMP on a wafer, the wafer comprising a first film and a second film, the first film covering the second film, as shown below. Figure 1 As shown, the chemical mechanical polishing control method includes steps S101, S102, S103, S104, and S105, specifically:

[0025] S101: Obtain polishing pressure information from the polishing head applied during chemical mechanical polishing of multiple historical wafers preceding the current wafer.

[0026] Optionally, the current wafer and multiple historical wafers can be consecutive wafers, and the chemical mechanical polishing (CMP) equipment can sequentially perform CMP polishing. The wafer surface is covered with a first thin film and a second thin film. Optionally, the first and second thin films can be non-metallic thin films. Optionally, the non-metallic thin films can be, for example, including but not limited to, TEOS (tetraethyl orthosilicate) films, Silicon films, and SiN (silicon nitride) films. (See reference...) Figure 2 The structural example shown has a first film covering a second film. During chemical mechanical polishing, the first film needs to be ground and removed to expose the second film.

[0027] Optionally, refer to Figure 3As shown, the chemical mechanical polishing (CMP) apparatus 100 may include a polishing head 101, a polishing disc 102, and a control device 103. The CMP control method of this application can be executed by the control device 103. Optionally, the polishing disc 102 includes a polishing pad. Optionally, the polishing head 101 can adsorb and transfer the wafer onto the polishing disc 102, and apply pressure to the wafer toward the polishing disc 102, thereby pressing the wafer onto the polishing pad of the polishing disc 102. The polishing disc 102 can rotate, and the polishing head 101 can drive the wafer to rotate relative to the polishing disc 102. With the assistance of polishing solutions, the polishing pad of the polishing disc 102 can grind the first thin film on the contacted wafer surface to perform CMP polishing.

[0028] Optionally, the polishing head 101 includes multiple pressure-applying areas for applying pressure to different areas of the wafer. Optionally, the polishing head 101 may include an elastic gas film, which includes multiple gas chambers. The wafer can be held in place by the elastic gas film, and pressure can be applied to different areas of the wafer by adjusting the gas pressure in the gas chambers.

[0029] Optionally, the multiple pressure-applying regions may include a circular pressure-applying region and multiple annular pressure-applying regions, with the circular region located at the center and the multiple annular pressure-applying regions arranged radially outwards from the circular region. Correspondingly, the multiple different regions of the wafer may include a circular region and multiple annular regions, with the multiple annular pressure-applying regions arranged radially outwards from the circular region, so that these multiple pressure-applying regions can correspondingly apply pressure to the multiple different regions on the wafer. For ease of explanation, we can take the polishing head in this application as having M polishing regions (M≥2 and an integer), and both the current wafer and the historical wafer having M different regions corresponding to the M polishing regions as an example. M can be determined according to the actual structure of the polishing head; for example, we can take M=7 as an example below, and denote the M=7 different regions of the wafer as Zone1, Zone2, ..., Zone7.

[0030] For ease of explanation, we can take multiple historical wafers, including N historical wafers (N≥2 and an integer), as an example. N can be chosen arbitrarily as needed. For example, in the following text, we can take N=3 as an example, and refer to the 3 historical wafers as the 1st, 2nd, and 3rd historical wafers respectively.

[0031] Optionally, multiple historical wafers can be consecutive wafers preceding and adjacent to the current wafer. For example, if the current wafer is the 4th wafer, then N=3 historical wafers could be the 1st, 2nd, and 3rd consecutive wafers preceding it. The same applies to the others.

[0032] Based on this, this application combines the relevant polishing pressure information of multiple consecutive wafers preceding and adjacent to the current wafer with the second thickness information to determine the target polishing pressure information for the current wafer. This can effectively ensure the uniformity of the thickness of the current wafer after polishing with the thickness of historical wafers, reduce the thickness variation of the wafer, and thus effectively improve the chemical mechanical polishing effect.

[0033] Optionally, the polishing pressure information includes: the polishing pressure values ​​applied by multiple pressure zones of the polishing head to multiple different areas of the historical wafer during chemical mechanical polishing. Optionally, in the following description, P can be used. j (i) represents the polishing pressure value corresponding to the j-th region among the M different regions of the i-th historical wafer in N historical wafers, where 1≤i≤N and 1≤j≤M.

[0034] For example, taking the i=1th historical wafer's Zone2 as an example, that is, when the i=1th historical wafer is chemically mechanically polished, the polishing pressure value applied by the j=2th pressure area of ​​the polishing head to the j=2nd zone2 of the i=1th historical wafer is P2(1), and the others can be deduced in the same way.

[0035] S102: Obtain the first thickness information of the first thin film of the current wafer before chemical mechanical polishing.

[0036] Reference Figure 2 The schematic diagram of the first and second thin films on the wafer illustrates that the first thickness information of the first thin film on the current wafer can be obtained by any suitable method before chemical mechanical polishing of the current wafer. For example, the first thickness information of the first thin film on the wafer can be obtained by real-time thickness detection. The first thickness information can reflect the state of the current wafer before polishing.

[0037] Optionally, the first thickness information includes: the first thickness values ​​of the first thin films in multiple different regions of the current wafer that are in contact with multiple pressure-applying regions before chemical mechanical polishing. Optionally, PreTHK may be used in the following description. j (N+1) represents the first thickness value of the first thin film in the j-th region among the M different regions of the current wafer, where 1≤j≤M.

[0038] For example, taking the current wafer's Zone2 as an example, that is, before chemical mechanical polishing, the first thickness value of the first thin film in Zone2, which is the j=2th pressure area of ​​the current wafer (equivalent to the N+1th wafer), is PreTHK2(N+1). The others can be deduced similarly.

[0039] S103: Obtain the second thickness information of the second thin film remaining after chemical mechanical polishing of multiple historical wafers.

[0040] During chemical mechanical polishing, it is generally necessary to grind away a portion of the second film to ensure that the first film is completely removed. (Refer to...) Figure 2 As shown, an example of the thickness of the second thin film on a wafer before it is polished is illustrated (e.g., ...). Figure 2 The upper boundary of this state is represented by a solid line, which includes the portion that will be removed and the remaining portion, and an example of the thickness of the second film remaining after chemical mechanical polishing (e.g.) Figure 2 (The upper boundary of this state is represented by a dashed line). It should be understood that the thickness ratio shown in the illustration does not represent an actual ratio and is only used for illustrative purposes. The second thickness information of the second film remaining after chemical mechanical polishing of multiple historical wafers can be obtained by any suitable method. For example, the second thickness information of the second film of the wafer can be obtained by real-time thickness detection. The second thickness information can reflect the chemical mechanical polishing results of the historical wafers.

[0041] Optionally, the second thickness information includes: the second thickness values ​​of the second thin film remaining in multiple different regions of the historical wafer after chemical mechanical polishing, wherein the multiple different regions of the historical wafer are subjected to pressure by multiple pressure-applying regions. Optionally, PostTHK may be used in the following description. j (i) represents the second thickness value of the remaining second film in the j-th region among the M different regions of the i-th historical wafer in N wafers, where 1≤i≤N and 1≤j≤M.

[0042] For example, taking the i=1th historical wafer's Zone2 as an example, that is, after the i=1th historical wafer is chemically mechanically polished, the second thickness value of the remaining second film in the j=2th zone2 of the i=1th historical wafer is PostTHK2(1), and the others can be deduced in the same way.

[0043] In this application, the polishing pressure information including multiple polishing pressure values, the first thickness information including multiple first thickness values, and the second thickness information including multiple second thickness values ​​are used to conveniently calculate the target polishing pressure values ​​for multiple regions of the current wafer. This is to improve the chemical mechanical polishing effect of the current wafer and effectively improve the thickness uniformity of the current wafer after chemical mechanical polishing and the historical wafer, reduce the thickness variation of the wafer, and thus effectively improve the chemical mechanical polishing effect.

[0044] S104: Determine the target polishing pressure information for the current wafer based on the polishing pressure information, the first thickness information, and the second thickness information.

[0045] This application does not limit the specific implementation of S104. Optionally, the target polishing pressure information includes target polishing pressure values ​​for different regions of the current wafer; multiple historical wafers are N historical wafers, the polishing head includes M polishing regions, and both the current wafer and the historical wafers include M different regions corresponding to the M polishing regions, where N≥2 and are integers, and M≥2 and are integers; step S104 includes:

[0046] Each target polishing pressure value in the target polishing pressure information is determined according to the following formula:

[0047]

[0048] Where 1≤i≤N, 1≤j≤M;

[0049] P j (N+1) represents the target polishing pressure value for the j-th region among the M different regions of the current wafer. It should be noted that the target polishing pressure value for the M different regions of the current wafer can be calculated using the above formula. This can be understood as M = 7 different regions, Zone1 to Zone7, thus obtaining the target polishing pressure value corresponding to the 7 different regions.

[0050] PreTHK j (N+1) represents the first thickness value of the first thin film in the j-th region among the M different regions of the current wafer.

[0051] PreTHK(N+1) ref This refers to the first thickness value of the first thin film in a reference region among M different regions of the current wafer. It should be noted that the reference region can be any region among the M different regions of the wafer, excluding the edges; the method of designation is not limited in this application. For example, the region whose first thickness value is closest to the average of the first thickness values ​​of these M different regions can be designated as the reference region. Taking M = 7 different regions (Zone1 to Zone7) of the current wafer as an example, the j = 5th region (Zone5) can be designated as the reference region, and the first thickness value of the first thin film in region Zone5 can be defined as PreTHK(N+1). ref .

[0052] P j (i) represents the polishing pressure value corresponding to the j-th region among the M different regions of the i-th historical wafer in N historical wafers.

[0053] PostTHK j (i) represents the second thickness value of the remaining second film in the j-th region among the M different regions of the i-th historical wafer.

[0054] PostTHK(i)ref This represents the second thickness value of the remaining second thin film in the reference region among the M different regions of the i-th historical wafer. It should be noted that the reference region has already been introduced and will not be repeated here. Assuming N=3 historical wafers are used, taking the M=7 different regions Zone1 to Zone7 of the i=1-th historical wafer as an example, the j=5th region Zone5 can be designated as the reference region, and the second thickness value of the second thin film in Zone5 can be defined as PostTHK(1). ref The same logic applies to the others.

[0055] w(i) represents the preset influence coefficient corresponding to the i-th historical wafer, and It should be noted that w(i) can be preset according to actual needs, and it can be used as a weight for weighted summation according to the above formula. Assuming that N=3 historical wafers are used, w(1), w(2) and w(3) can be preset, and w(1)+w(2)+w(3)=1 can be satisfied. The others can be deduced in the same way. For example, as one example, w(1)=0.7, w(2)=0.2, w(3)=0.1 can be set.

[0056] Zmt j This represents the preset reference removal thickness of the first thin film in the j-th region out of M distinct regions on the wafer when a polishing pressure of 1 psi is increased. It should be noted that psi is a unit of pressure, meaning "pounds per square inch," and Zmt... j It can be preset by engineers based on experience and is applicable to any wafer.

[0057] Zmb j This represents the preset reference removal thickness of the second thin film in the j-th region among M different regions of the wafer when the polishing pressure is increased by 1 psi. It should be noted that, similar to Zmt... j Similarly, Zmb j It can also be preset by engineers based on experience, and is applicable to any wafer.

[0058] Based on this, this application calculates each target polishing pressure value in the target polishing pressure information using the above formula, which more effectively combines the polishing pressure information of the historical wafers before the current wafer, the first thickness information of the first thin film before chemical mechanical polishing of the current wafer, and the second thickness information of the remaining second thin film after chemical mechanical polishing of the historical wafers, and takes them into consideration. Therefore, it can better achieve adaptive adjustment of polishing pressure for different wafers. By using the target polishing pressure values ​​for different regions of the current wafer calculated by the above formula, the polishing head of the chemical mechanical polishing equipment can be controlled to apply pressure to the current wafer. Chemical mechanical polishing of the current wafer can more effectively improve the thickness uniformity between the current wafer and the historical wafer after chemical mechanical polishing, and more effectively reduce the thickness variation of the wafer, thereby more effectively improving the chemical mechanical polishing effect.

[0059] Optionally, some preset default polishing pressure information and second thickness information can be provided in advance (which can be preset by engineers based on past experience). If there are no previous historical wafers for the current wafer (i.e., the current wafer is the first wafer to undergo chemical mechanical polishing), the preset default polishing pressure information and second thickness information can be used as the polishing pressure information and second thickness information of the historical wafers. Combined with the first thickness information corresponding to the current wafer, each target polishing pressure value in the target polishing pressure information for the current wafer can be calculated. If there are fewer than N previous historical wafers required by the above formula (e.g., N equals 3, and the current wafer is the second or third wafer, with only one or two previous historical wafers), the preset default polishing pressure information and second thickness information can be used to supplement the missing historical wafer polishing pressure information and second thickness information. Combined with the first thickness information corresponding to the current wafer, each target polishing pressure value in the target polishing pressure information for the current wafer can be calculated. This application does not impose specific limitations on the above situations.

[0060] S105: Based on the target polishing pressure information, control the polishing head of the chemical mechanical polishing equipment to apply pressure to the current wafer in order to perform chemical mechanical polishing on the current wafer.

[0061] Based on this, the chemical mechanical polishing control scheme selected in steps S101 to S105 of this application, when performing chemical mechanical polishing on the current wafer, combines the polishing pressure information of the previous historical wafers, the first thickness information of the first thin film before chemical mechanical polishing of the current wafer, and the second thickness information of the remaining second thin film after chemical mechanical polishing of the historical wafers, and comprehensively considers these factors to determine the target polishing pressure information for the current wafer. Therefore, it achieves adaptive adjustment of the polishing pressure for different wafers. By controlling the polishing head of the chemical mechanical polishing equipment to apply pressure to the current wafer through such polishing pressure information, the chemical mechanical polishing of the current wafer can be effectively improved to enhance the thickness uniformity between the current wafer and the historical wafers after chemical mechanical polishing, reduce the thickness variation of the wafer, and thus effectively improve the chemical mechanical polishing effect.

[0062] Optionally, for the optional implementation of obtaining multiple optional target polishing pressure values ​​as described above, step S105 includes: according to the determined M target polishing pressure values, controlling the M pressure application areas of the polishing head to apply pressure to the M different areas of the current wafer in a one-to-one correspondence, so as to perform chemical mechanical polishing on the current wafer.

[0063] For example, to obtain the target polishing pressure values ​​P1(N+1) to P7(N+1) corresponding to the M=7 different regions Zone1 to Zone7 for the current wafer, the M=7 pressure application areas of the polishing head are controlled to apply pressure to the regions Zone1 to Zone7 one by one with P1(N+1) to P7(N+1), thereby achieving chemical mechanical polishing of the current wafer.

[0064] Based on this, by controlling the polishing head to apply pressure to the current wafer through the above optional methods to achieve chemical mechanical polishing of the current wafer, the thickness uniformity of the current wafer after chemical mechanical polishing and the historical wafer can be effectively improved, and the thickness variation of the wafer can be reduced, thereby effectively improving the chemical mechanical polishing effect.

[0065] Optionally, the chemical mechanical polishing method in this application further includes: performing polishing endpoint detection during the chemical mechanical polishing of the current wafer, and stopping the chemical mechanical polishing of the current wafer when the termination condition of the polishing endpoint detection is met. Based on this, over-polishing of the current wafer can be avoided, thereby ensuring the effectiveness of the chemical mechanical polishing.

[0066] Optionally, an optional termination condition for polishing endpoint detection can be that the polishing time of chemical mechanical polishing reaches a time threshold. When the polishing time reaches the time threshold, the termination condition for polishing endpoint detection is considered met; if the polishing time does not reach the time threshold, the termination condition is considered not met. Optionally, the time threshold can be preset as needed. Optionally, the preset time threshold can be calculated in advance and then preset. For example, optionally, the required removal amount can be obtained by subtracting the target thickness from the current wafer's overall thickness. Dividing the removal amount by the removal rate yields the required grinding time for the current wafer. Alternatively, the time threshold can be set based on the required grinding time for the current wafer; for example, the time threshold can be set to the required grinding time, or set to be slightly larger than the required grinding time.

[0067] Based on this, the polishing pressure adjustment method and the polishing endpoint detection method can be combined to achieve both adaptive adjustment of polishing pressure and endpoint detection to stop the chemical mechanical polishing process. Optionally, the polishing time can be controlled solely by the polishing endpoint detection method, while the polishing pressure adjustment method is only used to adjust the polishing pressure of the wafer, avoiding the use of computational resources for polishing pressure adjustment during endpoint detection, thereby improving the calculation speed of the target polishing pressure information.

[0068] Alternatively, another optional method for detecting the polishing endpoint involves using a sensor to detect in real-time changes in the intensity of reflected light from the thin films on the wafer during chemical mechanical polishing, based on the reflectivity of the first and second thin films. This allows for the detection of intensity transitions in reflected light from different thin films during the chemical mechanical polishing process, and the polishing endpoint can be determined after a transition occurs. Therefore, the termination condition for polishing endpoint detection is determined based on the intensity of the reflected light. For example, the termination condition can be considered met when the intensity of the reflected light suddenly reaches a predetermined value, and not met when the intensity change does not reach the predetermined value.

[0069] Alternatively, another optional method for detecting the polishing endpoint can be based on the change in motor torque during the current wafer grinding process in chemical mechanical polishing. This method utilizes the different coefficients of friction of different thin films, which cause changes in the force and torque acting on the motor, thereby determining the transition of different thin films during the grinding process and controlling the polishing time. For example, the endpoint detection condition can be considered met when the sudden change in motor torque reaches a predetermined value, and not met when the torque change does not reach the predetermined value.

[0070] It should be noted that the above polishing endpoint detection method can be selected as needed, or other methods can be used, and this application does not impose any restrictions on this.

[0071] It should be understood that the above content is only some optional implementations of the chemical mechanical polishing control method of this application, and is not intended to limit this application in any way.

[0072] According to a second aspect of this application, a chemical mechanical polishing (CMP) apparatus is provided for chemically mechanically polishing a wafer, the wafer comprising a first thin film and a second thin film, the first thin film covering the second thin film, as shown below. Figure 3 As shown, the chemical mechanical polishing (CMP) apparatus 100 includes a polishing head 101, a polishing disk 102, and a control device 103, wherein the control device 103 is used to: acquire polishing pressure information of multiple historical wafers preceding the current wafer during CMP; acquire second thickness information of the second thin film remaining after CMP of the multiple historical wafers; determine target polishing pressure information for the current wafer based on the polishing pressure information, the first thickness information, and the second thickness information; and control the polishing head 101 to apply pressure to the current wafer based on the target polishing pressure information, so as to press the current wafer onto the polishing disk 102 for CMP.

[0073] It should be understood that the chemical mechanical polishing equipment 100 has been described in the previous embodiments and will not be repeated here.

[0074] According to a third aspect of this application, an electronic device is provided, comprising: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus; the memory is used to store a computer program; and the processor is used to execute the chemical mechanical polishing control method described in the first aspect by running the computer program stored in the memory.

[0075] Figure 4 A structural block diagram of an optional electronic device according to this application is shown. This application does not limit the specific implementation of the electronic device 400; however, as an example, reference is made to... Figure 4 The electronic device 400 provided in this application includes: a processor 402, a communications interface 404, a memory 406, and a communication bus 408. Wherein:

[0076] The processor 402, communication interface 404, and memory 406 communicate with each other via communication bus 408.

[0077] Communication interface 404 is used to communicate with other electronic devices or servers.

[0078] The processor 402 is used to execute the computer program 410, specifically the relevant steps in any of the aforementioned chemical mechanical polishing control method embodiments.

[0079] Specifically, computer program 410 may include program code that includes computer operation instructions.

[0080] Processor 402 may be a central processing unit (CPU), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement this application. The one or more processors included in the intelligent device may be processors of the same type, such as one or more CPUs; or they may be processors of different types, such as one or more CPUs and one or more ASICs.

[0081] Memory 406 is used to store computer program 410. Memory 406 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0082] Specifically, computer program 410 can be used to cause processor 402 to execute the chemical mechanical polishing control method in any of the foregoing embodiments.

[0083] The specific implementation of each step in computer program 410 can be found in the corresponding steps and units described in any of the foregoing embodiments of the chemical mechanical polishing control method, and will not be repeated here. Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the devices and modules described above can be referred to the corresponding process descriptions in the foregoing method embodiments, and will not be repeated here.

[0084] The electronic device 400 in this application has been described in detail in the aforementioned embodiments of the chemical mechanical polishing control method. Therefore, its related content and beneficial effects can be understood by referring to the above-mentioned method embodiments, and will not be repeated here.

[0085] According to a fourth aspect of this application, a computer storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the chemical mechanical polishing control method as described in the first aspect.

[0086] According to a fifth aspect of this application, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the chemical mechanical polishing control method as described in the first aspect.

[0087] According to a sixth aspect of this application, a chemical mechanical polishing control device is provided. Figure 5 This diagram illustrates a structural block diagram of an exemplary chemical mechanical polishing (CMP) control device 500 of this application. The CMP control device 500 of this embodiment is used for CMP polishing of a wafer, the wafer comprising a first thin film and a second thin film, the first thin film covering the second thin film. (Refer to...) Figure 5 As shown, the chemical mechanical polishing control device 500 includes:

[0088] The first acquisition module 501 is used to acquire polishing pressure information of multiple historical wafers before the current wafer during chemical mechanical polishing, which was applied by the polishing head.

[0089] The second acquisition module 502 is used to acquire the first thickness information of the first thin film of the current wafer before chemical mechanical polishing;

[0090] The third acquisition module 503 is used to acquire the second thickness information of the second thin film remaining after chemical mechanical polishing of the plurality of historical wafers;

[0091] The determination module 504 is used to determine the target polishing pressure information for the current wafer based on the polishing pressure information, the first thickness information, and the second thickness information.

[0092] The control module 505 is used to control the polishing head of the chemical mechanical polishing equipment to apply pressure to the current wafer according to the target polishing pressure information, so as to perform chemical mechanical polishing on the current wafer.

[0093] The embodiments of chemical mechanical polishing equipment 100 / electronic device 400 / computer storage medium / computer program product / chemical mechanical polishing control device 500 in this application are all based on the same inventive concept as the chemical mechanical polishing control method provided in the first aspect above. They have been described in detail in the various optional embodiments of the aforementioned chemical mechanical polishing control method. Therefore, their related contents and beneficial effects can be understood by referring to the above method embodiments, and will not be repeated here.

[0094] It should be noted that, depending on the implementation needs, the various components / steps described in this application can be broken down into more components / steps, or two or more components / steps or parts of the operation of a component / step can be combined into a new component / step to achieve the purpose of this application.

[0095] The methods described above according to this application can be implemented in hardware, firmware, or 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 as computer code originally stored on a remote recording medium or a non-transitory machine-readable medium and subsequently stored on a local recording medium, downloaded via a network. Thus, the methods described herein can be processed by software stored on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It is understood that the computer, processor, microprocessor controller, or programmable hardware includes storage components (e.g., RAM, ROM, flash memory, etc.) capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods described herein. Furthermore, when a general-purpose computer accesses the code used to implement the methods shown herein, the execution of the code transforms the general-purpose computer into a dedicated computer for executing the methods shown herein.

[0096] Those skilled in the art will recognize that the units and method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0097] The above embodiments are only used to illustrate this application and are not intended to limit this application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this application. Therefore, all equivalent technical solutions also fall within the scope of this application, and the patent protection scope of this application should be defined by the claims.

Claims

1. A chemical mechanical polishing control method for performing chemical mechanical polishing on a wafer, the wafer comprising a first thin film and a second thin film, the first thin film covering the second thin film, the method comprising: Obtain polishing pressure information from the polishing head applied during chemical mechanical polishing of multiple historical wafers preceding the current wafer; Obtain the first thickness information of the first thin film of the current wafer before chemical mechanical polishing; Obtain the second thickness information of the second thin film remaining after chemical mechanical polishing of multiple historical wafers; Based on the polishing pressure information, the first thickness information, and the second thickness information, determine the target polishing pressure information for the current wafer; Based on the target polishing pressure information, the polishing head of the chemical mechanical polishing equipment is controlled to apply pressure to the current wafer in order to perform chemical mechanical polishing on the current wafer; The polishing head includes multiple pressure-applying areas, which are used to apply pressure to different areas of the wafer. The polishing pressure information includes: the polishing pressure values ​​applied to multiple different areas of the historical wafer by multiple pressure-applying areas of the polishing head during chemical mechanical polishing; The first thickness information includes: the first thickness value of the first thin film in multiple different regions of the current wafer that are in contact with multiple pressure areas before chemical mechanical polishing; The second thickness information includes: the second thickness value of the second thin film remaining in multiple different regions of the historical wafer after chemical mechanical polishing, wherein the multiple different regions of the historical wafer are subjected to pressure by multiple pressure-applying regions; The target polishing pressure information includes target polishing pressure values ​​for different regions of the current wafer; multiple historical wafers are N historical wafers, the polishing head includes M polishing regions, and both the current wafer and historical wafers include M different regions corresponding to the M polishing regions, where N≥2 and are integers, and M≥2 and are integers; The step of determining the target polishing pressure information for the current wafer based on the polishing pressure information, the first thickness information, and the second thickness information includes: Each target polishing pressure value in the target polishing pressure information is determined according to the following formula: ; ; This represents the target polishing pressure value for the j-th region among the M different regions of the current wafer; This represents the first thickness value of the first thin film in the j-th region among the M different regions of the current wafer; The first thickness value of the first thin film in the reference region among the M different regions of the current wafer; This represents the polishing pressure value corresponding to the j-th region among the M different regions of the i-th historical wafer in N historical wafers; The second thickness value of the remaining second thin film in the j-th region among the M different regions of the i-th historical wafer; The second thickness value of the second thin film remaining in the reference region among the M different regions of the i-th historical wafer; This represents the preset influence coefficient corresponding to the i-th historical wafer, and ; The preset reference removal thickness represents the first thin film thickness of the j-th region among M different regions of the wafer when the polishing pressure is increased by 1 psi. The preset reference removal thickness represents the second thin film thickness of the j-th region among M different regions of the wafer when the polishing pressure is increased by 1 psi.

2. The method according to claim 1, wherein, The step of controlling the polishing head of the chemical mechanical polishing (CMP) equipment to apply pressure to the current wafer based on the target polishing pressure information, in order to perform CMP on the current wafer, includes: Based on the determined M target polishing pressure values, the M pressure application areas of the polishing head are controlled to apply pressure to the M different areas of the current wafer in a one-to-one correspondence, so as to perform chemical mechanical polishing on the current wafer.

3. The method according to any one of claims 1-2, wherein, The plurality of historical wafers are consecutive wafers preceding and adjacent to the current wafer.

4. The method according to any one of claims 1-2, wherein, The method further includes: performing a polishing endpoint detection during the chemical mechanical polishing of the current wafer, and stopping the chemical mechanical polishing of the current wafer when the termination condition of the polishing endpoint detection is met.

5. A chemical mechanical polishing (CMP) apparatus for performing CMP on a wafer using the CMP control method according to any one of claims 1-4, wherein the wafer comprises a first thin film and a second thin film, the first thin film covering the second thin film, and the CMP apparatus comprising: A polishing head, a polishing disc, and a control device, wherein: the control device is configured to: acquire polishing pressure information of multiple historical wafers preceding the current wafer during chemical mechanical polishing (CMP); acquire second thickness information of the second thin film remaining after CMP of the multiple historical wafers; determine target polishing pressure information for the current wafer based on the polishing pressure information, the first thickness information, and the second thickness information; and control the polishing head to apply pressure to the current wafer based on the target polishing pressure information to perform CMP on the current wafer.

6. An electronic device, comprising: The processor, the communication interface, the memory, and the communication bus are provided, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus. The memory is used to store computer programs; The processor is configured to perform the method of any one of claims 1-4 by running the computer program stored in the memory.

7. A computer storage medium having a computer program stored thereon, which, when executed by a processor, implements the method as described in any one of claims 1-4.

8. A computer program product comprising a computer program that, when executed by a processor, implements the method as described in any one of claims 1-4.

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