Chemical mechanical polishing method and apparatus

Abstract

The embodiment of the present application provides a chemical mechanical polishing method and device for wafer processing. The chemical mechanical polishing method comprises the following steps: obtaining historical polishing pressures of each area of a polishing head of a chemical mechanical polishing device; determining predicted removal rates of each area according to the obtained historical polishing pressures; the predicted removal rate of at least one area is determined according to the historical polishing pressure of the area and at least one other area other than the area; and determining polishing time required for current polishing and predicted polishing pressures of each area according to the predicted removal rates, the historical polishing pressures and a target removal amount of each area. In the embodiment of the present application, when determining the predicted removal rate of a certain area, not only the historical polishing pressure of the area itself is considered, but also the historical polishing pressures of other areas are considered, so that the predicted removal rate of each area can be more accurately predicted, the deviation between the actual removal amount of the wafer and the target removal amount is significantly reduced, and the phenomenon of local over-polishing or under-polishing is reduced.

Description

Technical Field

[0001] This application relates to the field of semiconductor wafer processing technology, and more particularly to a chemical mechanical polishing method and apparatus. Background Technology

[0002] In the field of semiconductor wafer fabrication technology, chemical mechanical polishing (CMP) is a process that combines chemical reactions and mechanical actions to smooth the surface of a wafer. Generally, the polishing head is divided into multiple zones, and different polishing pressures are applied to each zone during polishing to meet the polishing requirements of different parts of the wafer.

[0003] However, in related technologies, when polishing wafers, the polishing pressure applied to each area is the same as the pressure value of that area during the previous polishing. This results in a large difference between the actual removal amount and the target removal amount in each area, which seriously affects the polishing effect. Summary of the Invention

[0004] In view of this, embodiments of this application provide a chemical mechanical polishing method and apparatus to at least partially solve the above-mentioned problems.

[0005] According to a first aspect of the present application, a chemical mechanical polishing method is provided for wafer processing. The method includes the following steps: acquiring historical polishing pressures for each region of a polishing head of a chemical mechanical polishing apparatus; determining a predicted removal rate for each region based on the acquired historical polishing pressures; wherein the predicted removal rate for at least one region is determined based on the historical polishing pressures of that region and at least one other region outside that region; and determining the polishing time required for current polishing and the predicted polishing pressure for each region based on the predicted removal rate, historical polishing pressures, and target removal amount for each region.

[0006] Furthermore, in the above-mentioned chemical mechanical polishing method, the step of determining the predicted removal rate of each region based on the acquired historical polishing pressure further includes: establishing a multiple linear regression model between the removal rate of each region and the historical polishing pressure of that region and at least one other region outside that region; determining the weight value of the historical polishing pressure of each region in the multiple linear regression model; and determining the predicted removal rate of each region based on the determined multiple linear regression model, according to the historical polishing pressure of each region and the corresponding weight value.

[0007] Furthermore, in the above-mentioned chemical mechanical polishing method, determining the weight value of the historical polishing pressure of each region in the multiple linear regression model further includes: obtaining the historical removal rate of each region of the polishing head of the chemical mechanical polishing device; sequentially substituting the historical removal rate and historical polishing pressure of each region into the multiple linear regression model; and fitting the weight value of the historical polishing pressure of each region.

[0008] Furthermore, in the above-mentioned chemical mechanical polishing method, the step of determining the polishing time required for the current polishing and the predicted polishing pressure for each region based on the predicted removal rate, historical polishing pressure, and target removal amount for each region further includes: constructing a pressure constraint function based on the predicted polishing pressure and historical polishing pressure for each region; constructing a removal amount constraint function based on the target removal amount and predicted removal amount for the current polishing of each region; wherein the predicted removal amount is determined based on the predicted removal rate and the polishing time; constructing an objective function based on the pressure constraint function and the removal amount constraint function; and determining the polishing time and the predicted polishing pressure for each region based on the constructed objective function.

[0009] Furthermore, in the above chemical mechanical polishing method, the polishing time and the predicted polishing pressure of each region are determined based on the constructed objective function. In a further step, a single-objective optimization algorithm can be used to obtain the polishing time and the predicted polishing pressure of each region.

[0010] Furthermore, in the above chemical mechanical polishing method, the objective function constructed based on the pressure constraint function and the removal amount constraint function is:

[0011]

[0012] In the above formula: C is the objective function. Let i be the pressure constraint function for the i-th region. These are the weighting coefficients corresponding to the pressure constraint function of the i-th region. Let the historical polishing pressure of the i-th region be , The predicted polishing pressure for the i-th region is... Let j be the removal amount constraint function for the j-th region. These are the weighting coefficients corresponding to the removal amount constraint function of the j-th region. Let T be the target removal amount for the current polishing of the j-th region, and T be the polishing time. Let i be the current removal rate of the j-th region, where i takes the value of [1, n], j takes the value of [1, n], and n is the total number of polishing head regions.

[0013] Furthermore, in the above chemical mechanical polishing method, the pressure constraint function is: or ;in, It is the weight coefficient of the i-th region.

[0014] Furthermore, in the above chemical mechanical polishing method, the removal amount constraint function is: .

[0015] Furthermore, in the above-mentioned chemical mechanical polishing method, the area of ​​the polishing head includes an adjustable polishing pressure area; the area in which the historical polishing pressure of each area of ​​the polishing head of the chemical mechanical polishing device is obtained is the adjustable polishing pressure area.

[0016] Furthermore, in the above-mentioned chemical mechanical polishing method, the polishing head area also includes one or more polishing pressure fixing areas.

[0017] According to a second aspect of the embodiments of this application, a chemical mechanical polishing apparatus is provided, the apparatus comprising a base, a polishing disc, a polishing pad, a polishing liquid supply device, a polishing head, and a control unit; wherein the control unit is used to control the polishing pressure and polishing time of each region of the polishing head according to any of the above-described chemical mechanical polishing methods.

[0018] According to a third aspect of the embodiments of this application, an electronic device is provided. The device includes: a processor, a memory, a communication interface, and a communication bus, wherein the processor, the memory, and the communication interface communicate with each other via the communication bus; the memory stores at least one executable instruction, which causes the processor to perform an operation corresponding to any of the aforementioned chemical mechanical polishing methods.

[0019] According to a fourth aspect of the embodiments of this application, a computer storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements any of the above-described chemical mechanical polishing methods.

[0020] According to a fifth aspect of the embodiments of this application, a computer program product is provided, including computer instructions that instruct a computing device to perform an operation corresponding to any of the above-described chemical mechanical polishing methods.

[0021] The chemical mechanical polishing (CMP) method provided in this application addresses the issue that the polishing processes of different regions on the wafer surface are not entirely independent, as other regions can influence the material removal in the current region. Therefore, this application employs a more refined removal rate prediction process. When determining the predicted removal rate for a given region, it considers not only the historical polishing pressure of that region itself but also the historical polishing pressure of other regions. This cross-regional data analysis allows for a more accurate prediction of the predicted removal rate for each region, thereby optimizing the pressure distribution of the polishing head on the wafer. This significantly reduces the deviation between the actual and target removal amounts, improving the flatness of the entire wafer surface. It also enhances the uniformity and consistency of the wafer surface, reducing local over-polishing or under-polishing, ensuring the quality of the wafer in subsequent integrated circuit manufacturing, and ultimately improving the overall product reliability. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of 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 the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0023] Figure 1 A schematic diagram of the structure of a polishing apparatus for use with the chemical mechanical polishing method described in this application;

[0024] Figure 2 This application provides a schematic flowchart of a chemical mechanical polishing method.

[0025] Figure 3 This is a schematic diagram of the process for determining the predicted removal rate of each region in an embodiment of this application;

[0026] Figure 4 This application embodiment is a flowchart illustrating the process of determining the polishing time required for the current polishing and the predicted polishing pressure for each region;

[0027] Figure 5 This is a schematic diagram of the structure of an electronic device according to Embodiment 5 of this application. Detailed Implementation

[0028] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of 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 of this application, all other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of this application.

[0029] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0030] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0031] See Figure 1 The figure shows a polishing apparatus 100 applicable to the chemical mechanical polishing method proposed in the embodiments of this application. As shown, the polishing apparatus 100 mainly includes a base (not shown in the figure), a polishing disc 110, a polishing pad 120, a polishing slurry supply device 130, a dresser 140, a loading / unloading platform 150, and a polishing head 160. The polishing disc 110 is disposed on the base, and the polishing pad 120 is disposed on the polishing disc. The polishing disc 110 can drive the polishing pad 120 to rotate. The polishing slurry supply device 130 is used to supply polishing slurry to the polishing pad 120. The dresser 140 is used to maintain and dress the polishing pad 120. The loading / unloading platform 150 is disposed on one side of the polishing disc 110. The wafer is loaded onto the polishing head 160, and the polishing head 160 is configured to receive the wafer to be polished from the loading / unloading platform 150 or transfer the polished wafer to the loading / unloading platform 150.

[0032] During polishing, the polishing head 160 moves with the wafer toward the polishing pad 120 to press the wafer against the rotating polishing pad 120. Simultaneously, the polishing head 160 rotates with the wafer, and the polishing slurry supply device 130 injects a polishing slurry containing abrasives and chemical additives between the wafer and the polishing pad 120. Under the combined action of mechanical grinding and chemical reaction, the material on the wafer surface is uniformly removed, thereby achieving planarization.

[0033] Generally, the polishing head 160 is divided into multiple independent zones. During polishing, polishing pressure can be applied to each zone individually to meet the polishing requirements of different parts of the wafer. However, in related technologies, the previous polishing pressure of each zone is usually used as the current polishing pressure required for that zone. This results in a large deviation between the actual amount removed from the wafer and the target amount removed, which seriously affects the polishing effect.

[0034] Based on this, embodiments of this application propose a chemical mechanical polishing method to at least partially solve the above-mentioned problems.

[0035] The specific implementation of the embodiments of this application will be further described below with reference to the accompanying drawings.

[0036] See Figure 2 , Figure 2 A schematic flowchart of a chemical mechanical polishing method provided in an embodiment of this application is shown. As shown, the method includes the following steps:

[0037] Step S201: Obtain the historical polishing pressure of each region of the polishing head of the chemical mechanical polishing device.

[0038] Understandably, in chemical mechanical polishing (CMP), the polishing head is typically divided into multiple independent polishing zones. During polishing, polishing pressure is applied independently to each zone to meet the polishing requirements of different parts of the wafer.

[0039] For each region, the historical polishing pressure can be the previous polishing pressure for that region, the average polishing pressure over a certain period of time, or the maximum or minimum pressure over that period of time, etc., which can be determined according to the actual situation. This embodiment does not impose any limitations on it. The "certain period of time" can also be determined according to the specific situation, such as one day, one week, etc.

[0040] Step S202: Determine the current removal rate of each region based on the acquired historical polishing pressure. The current removal rate of at least one region is determined based on the historical polishing pressure of that region and at least one other region outside that region.

[0041] As can be understood, removal rate refers to the rate at which material is removed from the wafer surface per unit time. Specifically, it can refer to the thickness of material removed from the wafer surface per unit time by the pressure and friction applied to the wafer surface by the polishing head.

[0042] In actual polishing processes, the polishing processes of different regions on the wafer surface are not completely independent. The removal rate of each region is affected not only by the polishing pressure of its own region but also by the polishing pressure of other regions outside that region, and the closer the regions are, the greater the influence. Therefore, in calculating the predicted removal rate of each region in this application embodiment, the predicted removal rate of each region can be determined based on the historical polishing pressure of that region and at least one other region outside that region, or the predicted removal rate of some regions can be determined using this method, while the predicted removal rate of other regions can be determined only based on the historical polishing pressure of that region.

[0043] Specifically, in the embodiments of this application, two different methods can be adopted when calculating the predicted removal rate of each region: one method is to comprehensively consider the historical polishing pressure of the region and at least one other region outside the region to jointly determine the predicted removal rate of each region; the other method is to use this comprehensive consideration method only for some regions, while the predicted removal rate of other regions is calculated only based on the historical polishing pressure of the region.

[0044] For example, suppose the polishing head has three annular regions: region 1, region 2, and region 3, with region 2 located between region 1 and region 3. The predicted removal rate of region 1 can be determined based solely on the historical polishing pressures of regions 1 and 2, or regions 1 and 3, or simultaneously on the historical polishing pressures of regions 1, 2, and 3. The predicted removal rates of regions 2 and 3 can be determined solely on their respective historical polishing pressures, or, with reference to region 1, on the historical polishing pressures of their respective regions and any one or two other regions outside their respective regions. Since region 2 is closer to region 1 than region 3, the historical polishing pressure of region 2 has a greater impact on the predicted removal rate of region 1 than the historical polishing pressure of region 3. Therefore, when calculating the predicted removal rate of region 1 based on both regions 2 and 3, the weight of the historical polishing pressure of region 2 can be considered greater than that of region 3.

[0045] Step S203: Determine the polishing time required for the current polishing and the predicted polishing pressure for each region based on the predicted removal rate, historical polishing pressure, and target removal amount for each region.

[0046] The target removal amount is the amount of material removed from the wafer surface by the polishing head during the current polishing process; this value is a given, known amount.

[0047] For a given target removal amount, the higher the predicted removal rate in each region, the higher the predicted polishing pressure, and the less polishing time is required.

[0048] Since the polishing processes of different regions on the wafer surface are not completely independent, other regions can affect the material removal in the current region. Therefore, the chemical mechanical polishing process in this embodiment employs a more refined removal rate prediction. When determining the predicted removal rate for a certain region, it considers not only the historical polishing pressure of that region itself but also the historical polishing pressure of other regions. Through this cross-regional data analysis, the predicted removal rate for each region can be predicted more accurately, thereby optimizing the pressure distribution of the polishing head on the wafer. This significantly reduces the deviation between the actual removal amount and the target removal amount, improving the flatness of the entire wafer surface. It also improves the uniformity and consistency of the wafer surface, reduces local over-polishing or under-polishing, ensures the quality of the wafer in subsequent integrated circuit manufacturing, and ultimately improves the reliability of the overall product.

[0049] See Figure 3 , Figure 3 This is a flowchart illustrating the process of determining the predicted removal rate of each region based on the acquired historical polishing pressure in step S202 above. Specifically, it may include the following steps:

[0050] Step S301: Establish a multiple linear regression model between the removal rate of each region and the historical polishing pressure of that region and at least one other region outside that region.

[0051] During polishing, there are mutual coupling effects between different areas. Therefore, when calculating the removal rate of one area, the polishing pressure of other areas can be taken into account.

[0052] In one specific implementation, a multiple linear regression model can be established with the removal rate of each region as the dependent variable and the polishing pressure of each region as the independent variable. Specifically, the model can be:

[0053]

[0054] In the above formula, Let be the removal rate of the j-th region. For the first Polishing pressure in the area, , n is the total number of regions of the polishing head. When calculating the removal rate of the j-th region, the first... The weight value corresponding to the polishing pressure of each area This is random error.

[0055] It should be noted that, in practical implementation, a common total random error can be used when calculating the removal rate of each region. For example, assuming the polishing head has three regions: region 1, region 2, and region 3, then the removal rates of the three regions can be expressed as follows:

[0056] Y1= +

[0057] Y2= +

[0058] Y3= +

[0059] Of course, different random errors can be set for each region, and the specific method can be determined according to the actual situation. This embodiment does not impose any limitations here.

[0060] Step S302: Determine the weight values ​​of historical polishing pressure for each region in the multiple linear regression model.

[0061] In one specific implementation, the aforementioned weight values ​​can be fitted based on the historical removal rate and historical polishing pressure of each region.

[0062] Specifically, the historical removal rate data and corresponding historical polishing pressure data for each region of the polishing head in the chemical mechanical polishing (CMP) device are first obtained. Then, these data are sequentially input into a pre-defined multiple linear regression model, and statistical analysis methods are used to fit the weighted relationship between the historical polishing pressure and the removal rate for each region. In this process, mathematical fitting techniques such as the least squares method can be used to determine these weight values ​​to ensure the accuracy and reliability of the model. Through this fitting, we can obtain specific quantitative indicators of the impact of polishing pressure on the removal rate for each region, thereby providing data support for adjusting and optimizing the polishing process.

[0063] Step S303: Based on the determined multiple linear regression model, determine the predicted removal rate of each region according to the historical polishing pressure and corresponding weight values ​​of each region.

[0064] In step S301, once the weight values ​​in the multiple linear regression model are determined, this model can be used to predict the removal rate of each region. Specifically, historical polishing pressure data for each region can be input into the model, and the predicted removal rate for each region can be calculated by combining these historical polishing pressures with the weight values ​​fitted in step S302.

[0065] In practice, the historical polishing pressure can be the actual pressure value in the previous polishing operation, or the average value of multiple polishing pressure values, etc. It can be determined according to the actual situation, and this embodiment does not make any limitations.

[0066] See Figure 4 , Figure 4 for Figure 2 Step S203, which involves determining the polishing time and predicted polishing pressure for each region based on the predicted removal rate, historical polishing pressure, and target removal amount, can be illustrated with the following steps:

[0067] Step S401: Construct a pressure constraint function based on the predicted polishing pressure and historical polishing pressure of each region.

[0068] In one implementation, a pressure constraint function can be introduced to more precisely control the polishing pressure in each region. The basic form of this function can be: .in, Represents the historical polishing pressure in the current region. This represents the predicted polishing pressure for the i-th region. This function aims to... Searching nearby To find the optimal solution, the search range for the optimal solution is limited to avoid obtaining solutions that are detached from engineering practice.

[0069] Furthermore, considering that different regions on the wafer surface may have different physical properties and polishing requirements, the pressure constraint function can be further optimized. Specifically, weighting coefficients can be added to each term of the pressure constraint function for each region to form a weighted pressure constraint function in the following form: .in, This refers to the weighting coefficient for the i-th region. This weighting coefficient can be determined based on factors such as the material properties of the region, the polishing difficulty, and historical polishing results. In this way, different regions can be treated differently, making the model more accurate in predicting polishing pressure.

[0070] By introducing a weighted pressure constraint function, a more complete model can be obtained. This model not only considers the historical polishing pressure of each region, but also adapts to the specific polishing requirements of different regions on the wafer surface by adjusting the weight coefficients.

[0071] Step S402: Construct a removal amount constraint function based on the current target removal amount and predicted removal amount for each region. The predicted removal amount is determined based on the removal rate and polishing time.

[0072] In practical implementation, to precisely control the amount of material removed during chemical mechanical polishing (CMP), a removal amount constraint function can be defined. This function aims to constrain the target removal amount to a level close to the predicted removal amount, thus limiting the range for finding the optimal solution. The predicted removal amount is the product of the removal rate and the polishing time. The target removal amount for each region is a predefined, known quantity.

[0073] In one implementation, the expression for the removal amount constraint function can be: .in, The target material removal amount for the current polishing of the j-th region is the total amount of material that is desired to be removed in this region. For polishing time, Let be the removal rate of the j-th region.

[0074] In this embodiment, by applying a removal amount constraint function, it can be ensured that each area achieves the predetermined removal amount target within a given polishing time. The core function of this function is that it links the three key parameters—target removal amount, removal rate, and polishing time—forming a dynamic adjustment mechanism. In actual operation, if... A value that is not zero indicates a difference between the predicted removal amount and the target removal amount. In this case, it is necessary to adjust the polishing parameters, such as polishing pressure or polishing time, to reduce this difference.

[0075] Step S403: Construct the objective function based on the pressure constraint function and the removal amount constraint function.

[0076] In one specific implementation, the objective function can be:

[0077]

[0078] In the above formula: C is the objective function. Let i be the pressure constraint function for the i-th region. These are the weighting coefficients corresponding to the pressure constraint function of the i-th region. Let the historical polishing pressure of the i-th region be , The predicted polishing pressure for the i-th region is... Let j be the removal amount constraint function for the j-th region. These are the weighting coefficients corresponding to the removal amount constraint function of the j-th region. Let T be the target removal amount for the current polishing of the j-th region, and T be the polishing time. Let i be the current removal rate of the j-th region, where i takes the value of [1, n], j takes the value of [1, n], and n is the total number of polishing head regions.

[0079] In this implementation, the objective function is the sum of two parts: the first part is a function of the pressure constraint, and the second part is a function of the removal amount constraint. The weighting coefficients of the pressure constraint function... Weighting coefficients of the removal amount constraint function The pressure constraint function and the removal amount constraint function can be adjusted to the same magnitude so that they can be added together to form the objective function.

[0080] It should be noted that, in the actual implementation, and These are all predefined weighting coefficients. When setting these coefficients, the weighting coefficient for the region that has a greater impact on the overall wafer polishing is determined. and It should also be set to a larger value.

[0081] Step S404: Determine the polishing time and the predicted polishing pressure for each region based on the constructed objective function.

[0082] In practice, a single-objective optimization algorithm can be used to obtain the polishing time and the predicted polishing pressure for each region.

[0083] In one example, gradient descent can be used to find the optimal polishing time and the predicted polishing pressure for each region.

[0084] Specifically, the steps for solving the optimal polishing time and the predicted polishing pressure for each region using the gradient descent method are as follows:

[0085] Step 1, Initialize parameters: Randomly select an initial solution, including an initial polishing time. and the initial polishing pressure of each area Then set the initial learning rate (step size) for gradient descent; determine the stopping criteria, such as a preset number of iterations or a change in the objective function value that is less than a certain threshold.

[0086] Step 2, Calculate the gradient: Calculate the objective function. Regarding each parameter (polishing time) and polishing pressure in each area The gradient of the objective function. This typically involves calculating the partial derivatives of the objective function.

[0087] Step 3, Update Parameters: Update the polishing time using gradient and learning rate. and the initial polishing pressure of each area .

[0088] Evaluate the objective function: After updating the parameters, recalculate the objective function. The value of the parameter is used to evaluate whether the new parameter decreases the objective function value. If the preset number of iterations is reached or the change in the objective function is less than the stopping threshold, the iteration stops. Otherwise, return to step 2 and continue to the next iteration.

[0089] The algorithm stops when the stopping criterion is met, and outputs the final polishing time. and the initial polishing pressure of each area As the optimal solution.

[0090] In this embodiment, a single objective function is constructed, combining a pressure constraint function and a removal amount constraint function, to determine the optimal polishing time and the predicted polishing pressure for each region. Specifically, the pressure constraint function constrains the predicted polishing pressure within a reasonable range, thereby narrowing the search space for the optimal solution and ensuring that the predicted pressure does not deviate too far from the actual required polishing pressure. Simultaneously, the removal amount constraint function optimizes the polishing process, ensuring that the material removal amount in each polishing region reaches the predetermined target removal amount, and that this process is completed within the specified polishing time. By minimizing the objective function, this embodiment obtains a set of optimized polishing parameters, achieving a balance between polishing pressure and removal amount in each region of the wafer surface. This optimization process not only improves polishing efficiency but also ensures the uniformity of removal amount on the wafer surface, effectively avoiding local over-polishing or under-polishing problems, and minimizing wafer surface unevenness caused by uneven removal amount, thereby improving the overall quality of the wafer. Furthermore, this embodiment not only optimizes the wafer polishing process but also improves the yield and reliability in subsequent integrated circuit manufacturing, ensuring the performance and stability of the wafer throughout the entire production process.

[0091] In some implementations, the polishing head is divided into multiple adjustable polishing pressure zones. In the embodiments of this application, all zones involved in the steps of obtaining the historical polishing pressure of each zone of the polishing head of the chemical mechanical polishing apparatus, and determining the predicted removal rate of each zone based on these historical polishing pressures, refer to the adjustable polishing pressure zones. These adjustable zones allow for optimization of the polishing pressure during the polishing process to accommodate different polishing requirements.

[0092] Optionally, the polishing head may also include a polishing pressure fixing region that maintains constant pressure throughout the polishing process. One or more such regions may be provided, typically serving as a reference point during polishing or to meet specific process requirements. The presence of these fixed pressure regions ensures the stability of the polishing effect in certain critical areas while providing a reference standard for the entire polishing process. Through this distinction, this embodiment allows for more flexible control of the polishing process, optimization of removal rates, and maintenance of process consistency and reliability.

[0093] This application also proposes a chemical mechanical polishing (CMP) apparatus, which includes a base, a polishing disc, a polishing pad, a polishing slurry supply device, a polishing head, and a control unit. The control unit is used to control the polishing pressure and polishing time in each region of the polishing head according to any of the aforementioned CMP methods.

[0094] Since the above-mentioned chemical mechanical polishing method has the aforementioned effects, the chemical mechanical polishing device using this method also has the corresponding technical effects.

[0095] This application also proposes an electronic device. Figure 5 The diagram shows a structural schematic of an electronic device according to an embodiment of this application. The specific embodiments of this application do not limit the specific implementation of the electronic device.

[0096] like Figure 5 As shown, the electronic device may include: a processor 502, a communication interface 504, a memory 506, and a communication bus 508. The processor 502, communication interface 504, and memory 506 communicate with each other via the communication bus 508. The communication interface 504 is used to communicate with other electronic devices or servers. The processor 502 is used to execute program 510, specifically performing the relevant steps in the above-described chemical mechanical polishing method embodiments.

[0097] Specifically, program 510 may include program code that includes computer operation instructions.

[0098] Processor 502 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application. The smart device includes one or more processors, which may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0099] Memory 506 is used to store program 510. Memory 506 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0100] Specifically, program 510 can be used to cause processor 502 to perform the following operations:

[0101] The specific implementation of each step in procedure 510 can be found in the corresponding steps and units described in the above-described chemical mechanical polishing method embodiments, 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 equipment and modules described above can be referred to the corresponding process descriptions in the aforementioned method embodiments, and will not be repeated here.

[0102] The chemical mechanical polishing method of this embodiment can be executed by any suitable electronic device with data processing capabilities, including but not limited to: servers, mobile terminals (such as mobile phones, PADs, etc.) and PCs.

[0103] This application also proposes a computer storage medium storing a computer program that, when executed by a processor, implements a chemical mechanical polishing method as described above.

[0104] This application also proposes a computer program product, including computer instructions that instruct a computing device to perform operations corresponding to any of the above-described chemical mechanical polishing methods.

[0105] It should be noted that, depending on the implementation needs, the various components / steps described in the embodiments of this application can be broken down into more components / steps, or two or more components / steps or parts of the operation of components / steps can be combined into new components / steps to achieve the purpose of the embodiments of this application.

[0106] The methods described above according to the embodiments of this application can be implemented in hardware, firmware, or as software or computer code that can be stored in a recording medium (such as 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 stored on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA) for such software processing. 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 that, when accessed and executed by the computer, processor, or hardware, implements the chemical mechanical polishing method described herein. Furthermore, when a general-purpose computer accesses code for implementing the chemical mechanical polishing method shown herein, the execution of the code transforms the general-purpose computer into a dedicated computer for performing the chemical mechanical polishing method shown herein.

[0107] 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 the embodiments of this application.

[0108] The above embodiments are only used to illustrate the embodiments of this application, and are not intended to limit the embodiments of this application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of this application. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of this application, and the patent protection scope of the embodiments of this application should be defined by the claims.

Claims

1. A chemical mechanical polishing method for wafer processing, characterized in that, Includes the following steps: Obtain the historical polishing pressure of each region of the polishing head in a chemical mechanical polishing device; The predicted removal rate for each region is determined based on the obtained historical polishing pressure; wherein the predicted removal rate for at least one region is determined based on the historical polishing pressure of that region and at least one other region outside that region; The polishing time and the predicted polishing pressure for each region are determined based on the predicted removal rate, historical polishing pressure, and target removal amount for each region. The step of determining the predicted removal rate for each region based on the acquired historical polishing pressure includes: Establish a multiple linear regression model between the removal rate of each region and the historical polishing pressure of that region and at least one other region outside that region; Determine the weight values ​​of the historical polishing pressure for each region in the multiple linear regression model; Based on the established multiple linear regression model, the predicted removal rate of each region is determined according to the historical polishing pressure and corresponding weight values ​​of each region. The determination of the weight values ​​of the historical polishing pressure for each region in the multiple linear regression model includes: Obtain the historical removal rate of each region of the polishing head in a chemical mechanical polishing device; The historical removal rate and historical polishing pressure of each region were sequentially substituted into the multiple linear regression model. The weight values ​​of the historical polishing pressure for each region are fitted.

2. The chemical mechanical polishing method according to claim 1, characterized in that, The step of determining the polishing time required for the current polishing and the predicted polishing pressure for each region based on the predicted removal rate, historical polishing pressure, and target removal amount for each region further includes: A pressure constraint function is constructed based on the predicted polishing pressure and historical polishing pressure for each region. A removal amount constraint function is constructed based on the current target removal amount and the predicted removal amount for each region; wherein, the predicted removal amount is determined based on the predicted removal rate and the polishing time; Construct an objective function based on the pressure constraint function and the removal amount constraint function; The polishing time and the predicted polishing pressure for each region are determined based on the constructed objective function.

3. The chemical mechanical polishing method according to claim 2, characterized in that, Based on the constructed objective function, the polishing time and the predicted polishing pressure for each region are determined, further as follows: The polishing time and the predicted polishing pressure for each region can be obtained using a single-objective optimization algorithm.

4. The chemical mechanical polishing method according to claim 2, characterized in that, The objective function constructed based on the pressure constraint function and the removal amount constraint function is: In the above formula: C is the objective function. Let i be the pressure constraint function for the i-th region. These are the weighting coefficients corresponding to the pressure constraint function of the i-th region. Let the historical polishing pressure of the i-th region be , The predicted polishing pressure for the i-th region is... Let j be the removal amount constraint function for the j-th region. These are the weighting coefficients corresponding to the removal amount constraint function of the j-th region. Let T be the target removal amount for the current polishing of the j-th region, and T be the polishing time. Let i be the current removal rate of the j-th region, where i takes the value of [1, n], j takes the value of [1, n], and n is the total number of polishing head regions.

5. The chemical mechanical polishing method according to claim 4, characterized in that, The pressure constraint function is: or ;in, It is the weight coefficient of the i-th region.

6. The chemical mechanical polishing method according to claim 4, characterized in that, The removal amount constraint function is: .

7. The chemical mechanical polishing method according to any one of claims 1 to 6, characterized in that, The polishing head includes an area with adjustable polishing pressure. The regions in the historical polishing pressure data of each area of ​​the polishing head of the chemical mechanical polishing device are the adjustable polishing pressure regions.

8. The chemical mechanical polishing method according to claim 7, characterized in that, The polishing head area also includes one or more polishing pressure fixing areas.

9. A chemical mechanical polishing apparatus, characterized in that, It includes a base, a polishing disc, a polishing pad, a polishing fluid supply device, a polishing head, and a control unit; wherein the control unit is used to control the polishing pressure and polishing time of each region of the polishing head according to the chemical mechanical polishing method as described in any one of claims 1 to 8.

10. An electronic device, characterized in that, include: The processor, memory, communication interface, and communication bus are provided, wherein the processor, memory, and communication interface communicate with each other via the communication bus. The memory is used to store at least one executable instruction that causes the processor to perform the operation corresponding to the chemical mechanical polishing method as described in any one of claims 1-8.

11. A computer storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the chemical mechanical polishing method as described in any one of claims 1-8.

12. A computer program product, characterized in that, Includes computer instructions that instruct a computing device to perform operations corresponding to the chemical mechanical polishing method as described in any one of claims 1-8.

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