A method for precisely controlling pressure partition of a polishing head of a chemical mechanical polishing device

Abstract

The application relates to the technical field of pressure control, in particular to a polishing head pressure partition accurate control method of a chemical mechanical polishing device. The application realizes self-adaptive accurate regulation and control of pressure partition by integrating multi-dimensional sensors to collect key data such as basic conditions of the polishing device and wafer topography in real time, combining intelligent analysis to carry out dynamic analysis and damage prediction, can automatically optimize and adapt pressure load, significantly improves polishing uniformity and process stability, effectively prevents wafer damage, and thus improves the yield and material utilization.

Description

Technical Field

[0001] This application relates to the field of pressure control technology, and in particular to a method for precise control of pressure zones in the polishing head of a chemical mechanical polishing device. Background Technology

[0002] Chemical mechanical polishing (CMP) is a key process in semiconductor manufacturing for achieving global wafer planarization. It uses a polishing head to apply pressure to the wafer surface in conjunction with a polishing slurry to achieve high-precision material removal. However, traditional CMP equipment often faces problems such as uneven pressure distribution, inconsistent polishing pad wear, wafer surface damage (e.g., microcracks, scratches), and edge effects during polishing, severely impacting polishing uniformity and yield. Especially at advanced process nodes, the requirements for consistent surface roughness, defect control, and material removal rates are becoming increasingly stringent, and existing pressure control methods struggle to meet the demands for high precision and adaptive adjustment.

[0003] Currently, most CMP equipment employs fixed-zone pressure control or pressure adjustment strategies based on simple feedback, lacking real-time monitoring and comprehensive analysis of polishing pad condition, wafer surface morphology, and material properties. During polishing, the polishing head may deform or change its surface smoothness due to prolonged use, leading to a decrease in pressure transmission efficiency. Simultaneously, defects such as wafer hardness and internal microcracks are prone to propagate under polishing stress, further exacerbating surface damage. Existing technologies often fail to dynamically correlate polishing head condition, wafer properties, and the evolution of polishing damage, resulting in lagging and insufficiently precise pressure control, making it difficult to achieve accurate optimization of zoned pressure.

[0004] Therefore, there is an urgent need for an intelligent control method that can sense the state of the polishing pad and the wafer in real time, predict the damage propagation trend, and dynamically adjust the partition pressure accordingly, so as to improve the stability, uniformity and defect control capability of the polishing process and meet the stringent requirements of high-end semiconductor manufacturing for CMP process. Summary of the Invention

[0005] To overcome the defects and shortcomings of existing technologies, this application integrates multi-dimensional sensors to collect key data such as the basic condition of polishing equipment and wafer morphology in real time. Combined with intelligent analysis, it performs dynamic analysis and damage prediction to achieve adaptive and precise control of pressure zones. This enables automatic optimization and adaptation of pressure load, significantly improving polishing uniformity and process stability, effectively preventing wafer surface damage, and thus improving yield and material utilization.

[0006] To achieve the above objectives, this application adopts the following technical solution:

[0007] In a first aspect, this application provides a method for precise control of the pressure zone of the polishing head in a chemical mechanical polishing device, comprising the following specific steps:

[0008] Step 1: Obtain information on the surface condition of the polishing head of the polishing equipment, the smoothness of the polishing wafer at each corresponding location, the presence of cracks, and the frictional properties.

[0009] Step 2: Analyze the surface condition of the polishing head to identify any abnormalities in its operation. Analyze the abnormalities in the polishing process by examining the surface condition of the polishing head and its friction properties.

[0010] The analysis of the abnormal operation of the polishing head includes the following specific steps:

[0011] The first step is to acquire images of the polishing head and the operational deviation of the control commands, and to detect any abnormalities in the smoothness of the polishing head's surface or the deformation of the polishing head relative to the initial stage.

[0012] The second step is to obtain the average vibration amplitude and vibration frequency of the polishing head at the corresponding rotation speed. The amplitude abnormality is obtained by dividing the average vibration amplitude by the safe amplitude, the vibration frequency abnormality is obtained by dividing the vibration frequency by the safe vibration frequency, and the vibration abnormality is obtained by multiplying the amplitude abnormality and the vibration frequency abnormality.

[0013] The third step involves obtaining abnormalities in the smoothness, deformation, and vibration of the polishing head, and then performing a weighted summation to determine the abnormalities in the polishing head's operation. The analysis of polishing process abnormalities includes the following specific aspects:

[0014] The first step is to obtain the calculated abnormal operation of the polishing head and the mechanical damping of the material. The mechanical damping is the loss factor or attenuation coefficient of the force transmitted inward per unit distance.

[0015] The second step is to obtain the attenuation by multiplying the depth of the crack by the mechanical damping condition, and then multiplying the difference between the attenuation and the value of 1 by the polishing head operation abnormality to obtain the abnormal impact of the polishing process on the crack.

[0016] Step 3: Predict the propagation of polishing damage by analyzing the smoothness of the corresponding locations on the polished wafer and the condition of surrounding cracks.

[0017] The polishing damage propagation prediction includes the following specific details:

[0018] The first step is to obtain the size of the crack and the smoothness of the corresponding positions on the polished wafer; the crack anomaly is obtained by dividing the crack volume by the crack safety volume, and the crack propagation prediction anomaly is obtained by multiplying the crack anomaly by the impact of the polishing process on the crack.

[0019] The second step is to obtain the smoothness anomaly of the wafer by dividing the smoothness to be achieved after polishing by the smoothness of the corresponding position on the wafer.

[0020] Step 4: Analyze the polishing pressure in the area based on the results of polishing process anomalies, hardness, and polishing damage propagation predictions.

[0021] Step 5: Release the polishing pressure based on the obtained regional polishing pressure analysis results.

[0022] In one implementation of this application, the surface condition of the polishing head includes an image of the polishing head and the vibration amplitude and frequency generated during the operation of the polishing head. The image is acquired by a three-dimensional image acquisition component and is used to analyze abnormal operation of the polishing head. The smoothness of each corresponding position of the polished wafer is a three-dimensional image of the polished wafer surface acquired by an image acquisition module. The crack condition is the size and depth of the acquired cracks. The friction properties are the hardness of the corresponding wafer and the mechanical damping of the material, used to analyze the damage to the cracks inside the wafer during the polishing process.

[0023] In one implementation of this application, the area polishing pressure analysis includes the following specific steps:

[0024] Obtain the smoothness anomaly, hardness, and polishing head operation anomaly of the corresponding wafer; obtain the wafer's hardness anomaly by dividing the wafer's hardness by the safe hardness; obtain the wafer's wear resistance value by taking the weighted sum of the smoothness anomaly and the wafer's hardness anomaly and then taking the reciprocal. It should be noted that, to avoid the denominator being 0 and meaningless when calculating the reciprocal, a minimum value that does not affect the numerical value needs to be added to the denominator during the calculation. This is a conventional technique; obtain the wafer's polishing anomaly by taking the weighted sum of the wafer's wear resistance value and the polishing head operation anomaly.

[0025] The overall polishing process anomaly is obtained by weighted summation of wafer polishing anomaly and crack propagation prediction anomaly. The safe pressure range of the polishing equipment is obtained. The overall polishing process anomaly threshold is divided by the overall polishing process anomaly to obtain the quotient. If the result is greater than 1, it indicates that the corresponding wafer will be damaged during polishing, and it is recommended to replace the polishing equipment. The safe pressure range of the polishing equipment is scaled proportionally to the range between 0 and 1. The quotient of the overall polishing process anomaly divided by the overall polishing process anomaly threshold is obtained. The pressure value obtained is the pressure required for polishing.

[0026] Overall outliers reflect the comprehensive balance between quality, efficiency, and risk during the polishing process. By mapping them to the safe pressure range, risk adaptive control can be achieved. When the outlier is high (high risk), the pressure is automatically reduced to avoid damage, while the pressure can be increased to improve efficiency. At the same time, the health status warning of the polishing equipment is realized through quotient judgment (such as result > 1), providing a quantitative basis for production decisions (such as equipment replacement).

[0027] Secondly, this application also provides a method for precise control of the pressure zone of the polishing head in a chemical mechanical polishing device, including the following specific modules:

[0028] The system includes a data acquisition module, a polishing process analysis module, a damage propagation prediction module, a polishing pressure analysis module, and a pressure release module.

[0029] The data acquisition module is used to acquire information about the surface condition of the polishing head of the polishing equipment, the smoothness, crack conditions, and friction properties of the corresponding positions of the polishing wafer.

[0030] The polishing process analysis module is used to analyze the abnormal operation of the polishing head by examining the surface condition of the polishing head of the polishing equipment, and to analyze the abnormal operation of the polishing head and the friction properties to analyze the abnormality of the polishing process.

[0031] The damage propagation prediction module predicts the propagation of polishing damage by considering the smoothness of the polished wafer at corresponding locations and the condition of surrounding cracks.

[0032] The polishing pressure analysis module performs regional polishing pressure analysis based on polishing process anomalies, hardness, and polishing damage propagation prediction results.

[0033] The pressure release module releases polishing pressure based on the obtained regional polishing pressure analysis results.

[0034] Thirdly, this application provides an electronic device comprising: a processor and a memory, wherein the memory stores a computer program that can be called by the processor, and the processor executes a method for precise control of the pressure zone of a polishing head in a chemical mechanical polishing device by calling the computer program stored in the memory.

[0035] Fourthly, this application provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform a method for precise control of the pressure zone of a polishing head in a chemical mechanical polishing device.

[0036] Compared with the prior art, this application has the following advantages:

[0037] By integrating multi-dimensional sensors to collect key data such as the basic condition of the polishing equipment and the morphology of the wafer in real time, and combining intelligent analysis for dynamic analysis and damage prediction, the system can achieve adaptive and precise control of pressure zones. It can automatically optimize and adapt to pressure load, significantly improve polishing uniformity and process stability, effectively prevent wafer damage, and thus improve yield and material utilization. Attached Figure Description

[0038] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0039] Figure 1 This is a schematic diagram of the overall process structure of the method in this application;

[0040] Figure 2 This is a schematic diagram illustrating the abnormal operation process of the polishing head analyzed by the method of this application;

[0041] Figure 3 This is a schematic diagram of the system structure of this application. Detailed Implementation

[0042] The technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of this application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other.

[0043] Please see Figures 1 to 2 , Figure 1 This is a schematic diagram of the overall process of a method for precise control of polishing head pressure zones in a chemical mechanical polishing device provided in this application embodiment, which specifically includes the following steps:

[0044] Step 1: Obtain information on the surface condition of the polishing head of the polishing equipment, the smoothness of the polishing wafer at each corresponding location, the presence of cracks, and the frictional properties.

[0045] In this embodiment, the surface condition of the polishing head includes the image of the polishing head, the vibration amplitude and frequency generated by the operation of the polishing head; the image is acquired by a three-dimensional image acquisition component and used to analyze abnormal operation of the polishing head; the smoothness of each position of the polishing wafer is obtained by the three-dimensional image of the polishing wafer surface acquired by the image acquisition module, and the crack condition is the size and depth of the cracks acquired; the friction properties are the hardness of the corresponding wafer and the mechanical damping of the material, used to analyze the damage to the cracks inside the wafer during the polishing process;

[0046] In this step, images of the polishing head are acquired using a 3D laser scanner or a high-precision confocal microscope, with resolution typically set at the micrometer level (e.g., 1-10 micrometers) to accurately reconstruct the surface morphology. The amplitude and frequency of vibrations are collected in real-time by an accelerometer integrated on the polishing head spindle, with a sampling frequency at least twice the highest operating frequency of the polishing head (according to the Nyquist theorem). For example, if the highest rotational speed of the polishing head corresponds to a frequency of 200 Hz, the sampling frequency should be no less than 400 Hz. The smoothness of the polished wafer surface is also obtained using an online or offline 3D surface profilometer, with a lateral resolution at the sub-micrometer level and a longitudinal resolution at the nanometer level to accurately assess surface roughness (Ra, Rz, etc.). The size and depth of cracks can be obtained using a scanning acoustic microscope (SAM) or a laser ultrasonic testing system, with a detection depth resolution typically set at the micrometer level. The hardness of the wafer is obtained by averaging measurements at multiple representative locations on the wafer using a nanoindenter, while the mechanical damping (loss factor or attenuation coefficient) of the material is experimentally determined using a dynamic mechanical analyzer at simulated polishing conditions at different frequencies and temperatures.

[0047] Step 2: Analyze the surface condition of the polishing head to identify any abnormalities in its operation. Analyze the abnormalities in the polishing process by examining the surface condition of the polishing head and its friction properties.

[0048] In this embodiment, the analysis of abnormal polishing head operation includes the following specific steps:

[0049] The first step involves acquiring images of the polishing head and monitoring deviations in control commands. This includes identifying surface smoothness anomalies and deformation anomalies relative to the initial stage. Polishing can easily cause hard deformation or smoothing of the polishing head. The smoothness of the polishing head is determined by dividing the average height of each point relative to the standard surface by the safety height, then taking the reciprocal of the quotient. For smoothness anomalies, a significant difference in smoothness compared to the original smoothness makes wafer polishing difficult, requiring higher pressure; conversely, a smaller difference can easily damage the wafer, requiring lower pressure. The smoothness anomaly is calculated as the difference between the original smoothness and the current smoothness, divided by the original smoothness. For deformation anomalies relative to the initial stage, the deformation volume of the polishing head relative to the initial stage is divided by the volume of the polishing head in the initial stage.

[0050] In this step, the surface condition (smoothness, deformation) of the polishing head is precisely quantified through three-dimensional images, providing a direct basis for pressure control. Since the change in the smoothness of the polishing head directly affects the friction coefficient and pressure transmission efficiency between it and the wafer, and the deformation reflects the structural integrity of the polishing head, the two together determine the polishing uniformity. The advantage is that it realizes an objective and quantitative assessment of the polishing head condition and avoids the errors of traditional experience judgment.

[0051] The second step is to obtain the average vibration amplitude and vibration frequency of the polishing head at the corresponding rotation speed. The amplitude abnormality is obtained by dividing the average vibration amplitude by the safe amplitude, the vibration frequency abnormality is obtained by dividing the vibration frequency by the safe vibration frequency, and the vibration abnormality is obtained by multiplying the amplitude abnormality and the vibration frequency abnormality.

[0052] In this step, the dynamic operational stability of the polishing head is monitored. Since abnormal vibrations often originate from polishing head imbalance, wear, or drive system failure, they can directly lead to polishing pressure fluctuations and scratches on the wafer surface. This step, through comprehensive analysis of amplitude and frequency, can identify mechanical faults or assembly problems in the early stages, enabling preventive maintenance, reducing batch defects caused by equipment abnormalities, and improving process stability.

[0053] The third step is to obtain abnormalities in the smoothness, deformation, and vibration of the polishing head, and then perform a weighted summation to obtain the abnormalities in the operation of the polishing head.

[0054] In this step, the initial smoothness of the polishing head is taken as the benchmark based on the initial measurement of a new polishing head or a polishing head after standard repair; the safety height is set according to the material properties and process specifications of the polishing head, usually taking the maximum allowable wear depth threshold; the safety amplitude and safety vibration frequency are set according to the tolerance range provided by the equipment manufacturer or the statistical upper limit value during long-term stable operation; when analyzing abnormalities in the polishing process, mechanical damping parameters (such as attenuation coefficient) are obtained through standard material testing methods, or by the material supplier providing typical values ​​at specific frequencies; the safety volume of cracks is calculated based on the maximum allowable defect size in the wafer quality acceptance standard; in this step, the performance of the polishing head is a comprehensive reflection of surface condition, structural deformation, and dynamic stability, and the weighted sum can reflect the contribution of each factor; this step provides a comprehensive indicator reflecting the health status of the polishing head, facilitating the system to quickly determine whether process parameters need to be adjusted or equipment maintenance performed.

[0055] In this embodiment, the analysis of polishing process anomalies includes the following specific aspects:

[0056] The first step is to obtain the calculated abnormal operation of the polishing head and the mechanical damping of the material. The mechanical damping can be the loss factor or attenuation coefficient of the force transmitted inward per unit distance, which is obtained through experiments.

[0057] The second step is to obtain the attenuation condition by multiplying the depth of the crack by the mechanical damping condition. The difference between the attenuation condition and the value of 1 is multiplied by the abnormal operation of the polishing head to obtain the abnormal impact of the polishing process on the crack. The attenuation condition is the attenuation ratio of the external vibration force transmitted to the crack location during the polishing process.

[0058] Step 3: Predict the propagation of polishing damage by analyzing the smoothness of the corresponding locations on the polished wafer and the condition of surrounding cracks.

[0059] In this embodiment, the polishing damage propagation prediction includes the following specific aspects:

[0060] The first step is to obtain the size of the crack and the smoothness of the corresponding positions on the polished wafer; the crack anomaly is obtained by dividing the crack volume by the crack safety volume, and the crack propagation prediction anomaly is obtained by multiplying the crack anomaly by the impact of the polishing process on the crack.

[0061] This step quantifies the potential risk of the polishing process exacerbating internal defects (such as cracks) in the wafer; the material damping properties determine the stress dissipation capacity at the crack tip; abnormal polishing head increases local stress, and the two coupled affect the crack propagation trend. For the first time, the polishing head state is dynamically correlated with the wafer material properties, realizing the risk prediction of hidden damage (internal cracks) and providing a basis for protective polishing strategies.

[0062] The second step is to obtain the smoothness anomaly of the wafer by dividing the smoothness to be achieved after polishing by the smoothness of the corresponding position on the wafer.

[0063] The safe volume threshold for cracks is calculated based on fracture mechanics principles and the critical stress intensity factor of the wafer material, or directly adopts the defect specifications allowed for wafers at specific technology nodes in industry standards. The target smoothness to be achieved after polishing is explicitly set according to the surface roughness requirements of downstream processes (such as photolithography), usually a specific roughness value. These thresholds and targets are directly derived from product technical specifications or process design documents.

[0064] This step assesses the risk of defect propagation and the surface polishing quality requirements; crack volume reflects the severity of existing damage; the gap between the target and the current smoothness defines the polishing process requirements; and it provides a two-way constraint for subsequent pressure optimization, which helps to minimize damage risk while ensuring polishing effect.

[0065] Step 4: Analyze the polishing pressure in the area based on the results of polishing process anomalies, hardness, and polishing damage propagation predictions.

[0066] In this embodiment, the area polishing pressure analysis includes the following specific steps:

[0067] Obtain the smoothness anomaly, hardness, and polishing head operation anomaly of the corresponding wafer; obtain the wafer's hardness anomaly by dividing the wafer's hardness by the safe hardness; obtain the wafer's wear resistance value by taking the weighted sum of the smoothness anomaly and the wafer's hardness anomaly and then taking the reciprocal. It should be noted that, to avoid the denominator being 0 and meaningless when calculating the reciprocal, a minimum value that does not affect the numerical value needs to be added to the denominator during the calculation. This is a conventional technique; obtain the wafer's polishing anomaly by taking the weighted sum of the wafer's wear resistance value and the polishing head operation anomaly.

[0068] The overall polishing process anomaly is obtained by weighted summing of wafer polishing anomalies and crack propagation prediction anomalies. The safe pressure range of the polishing equipment is then determined. The overall polishing process anomaly threshold is divided by the overall polishing process anomaly threshold to obtain the quotient. If the quotient is greater than 1, it indicates that the corresponding wafer will be damaged during polishing, and it is recommended to replace the polishing equipment. The safe pressure range of the polishing equipment is then proportionally scaled down to between 0 and 1. The quotient of the overall polishing process anomaly divided by the overall polishing process anomaly threshold is obtained and compared with the proportionally scaled result. The resulting pressure value is the pressure required for polishing. For example, for a standard 300mm wafer, to generate the required polishing pressure, the force applied by the equipment's bearing head at the corresponding position is approximately 1000 Newtons to 3000 Newtons. If the quotient of the overall polishing process anomaly threshold divided by the overall polishing process anomaly is 0.85, then the force applied by the equipment's bearing head at the corresponding position is 2700 Newtons.

[0069] In this step, the safe hardness is taken as the median or lower limit of the standard hardness range of the wafer material grade; the overall polishing process anomaly threshold is an empirical critical value, usually determined by statistical analysis of the overall polishing process anomalies in successful and failed (damaged) cases in historical production data (such as using the decision boundary of a machine learning classification model or the upper control limit of statistical process control); the safe pressure range of the polishing equipment is strictly set according to the rated pressure working range of the bearing head for the corresponding wafer size specified in the polishing equipment manufacturer's technical manual (e.g., 1000-3000 N); the minimum value added in the calculation to prevent division by zero errors is usually a number much smaller than the normal calculated value, such as 1e-10;

[0070] Overall outliers reflect the comprehensive balance between quality, efficiency, and risk during the polishing process. By mapping them to the safe pressure range, risk adaptive control can be achieved. When the outlier is high (high risk), the pressure is automatically reduced to avoid damage, while the pressure is increased to improve efficiency. At the same time, the health status warning of the polishing equipment is realized through quotient judgment (such as result > 1), providing a quantitative basis for production decisions (such as equipment replacement).

[0071] Step 5: Release the polishing pressure based on the obtained regional polishing pressure analysis results;

[0072] The required pressure for polishing at each location is obtained from the analysis, and the required pressure is released at the corresponding location during polishing by controlling the components through a PLC.

[0073] Specifically, the PLC receives a pressure distribution matrix or pressure command table from the host computer via industrial Ethernet or fieldbus. This data typically includes: dividing the polishing head's working area into an MxN grid; the ideal polishing pressure (units: Newtons, Pascals, or percentage) corresponding to each grid cell, calculated through analysis; if the pressure needs to change dynamically over time, the data will include timestamps or process step information. After receiving the data, the PLC's CPU parses it and stores it in a specific data block (DB) or register area for subsequent control logic calls. The PLC obtains the precise position (X, Y coordinates and rotation angle) of the polishing head (or wafer carrier) in real time through an encoder or servo driver. Based on the current position, the PLC quickly retrieves the target pressure values ​​corresponding to all execution units below the polishing head from the stored pressure distribution data block using a preset mapping algorithm. Pressure setpoint output: For each independent pressure control unit (such as a pneumatic proportional valve or an electric servo cylinder), the PLC uses the retrieved target pressure value as the setpoint. The PLC outputs the SP value to the corresponding analog output (AO) module (to control the proportional valve current) or directly sends it to the servo driver via motion control commands (to control the servo cylinder force). Each pressure actuator is equipped with a pressure sensor (such as piezoelectric or strain gauge type). The sensor signal is fed back to the PLC in real time via the analog input (AI) module as a process value. Deviation calculation and adjustment: The PLC's internal PID control function block continuously calculates the deviation. Control output: The PID algorithm dynamically calculates the control signal (such as adjusting the opening of the proportional valve or the current of the servo motor) based on the magnitude, direction, and trend of the deviation, and outputs it through the AO module to drive the actuator to accurately reach and maintain the target pressure.

[0074] It should be noted that the conventional technical means used in this embodiment will not be described in detail.

[0075] It should be noted that the setting parameters (weights and thresholds) in this embodiment are obtained as follows: the surface condition of the polishing head of the polishing equipment in the historical polishing process, the smoothness, cracks, and friction properties of the corresponding positions of the polished wafer; the polishing force and the judgment result of whether the polishing meets the production requirements; the surface condition of the polishing head of the polishing equipment in the historical polishing process, the smoothness, cracks, and friction properties of the corresponding positions of the polished wafer, are imported into this embodiment to calculate the pressure required for polishing; the judgment result of meeting the production requirements and the calculation result of the embodiment are imported into fitting software (such as MATLAB) for linear fitting of the data; and the value of the setting parameter that meets the maximum judgment accuracy is output.

[0076] The overall benefits of this solution are as follows: By integrating multi-dimensional sensors to collect key data such as the basic condition of the polishing equipment and the morphology of the wafer in real time, and combining intelligent analysis for dynamic analysis and damage prediction, the solution enables adaptive and precise control of pressure zones. It can automatically optimize and adapt to pressure loads, significantly improve polishing uniformity and process stability, effectively prevent wafer damage, and thus improve yield and material utilization.

[0077] Please see Figure 3 , Figure 3 This is a schematic diagram of a method for precise control of polishing head pressure zones in a chemical mechanical polishing device according to an embodiment of this application, including:

[0078] Includes the following specific modules:

[0079] The system includes a data acquisition module, a polishing process analysis module, a damage propagation prediction module, a polishing pressure analysis module, and a pressure release module.

[0080] The data acquisition module is used to acquire information about the surface condition of the polishing head of the polishing equipment, the smoothness, crack conditions, and friction properties of the corresponding positions on the polishing wafer;

[0081] The polishing process analysis module is used to analyze polishing head operation abnormalities by examining the surface condition of the polishing head in the polishing equipment, and to analyze polishing process abnormalities by examining polishing head operation abnormalities and friction properties.

[0082] The damage propagation prediction module predicts the propagation of polishing damage by considering the smoothness of the polished wafer at corresponding locations and the condition of surrounding cracks.

[0083] The polishing pressure analysis module performs regional polishing pressure analysis based on polishing process anomalies, hardness, and polishing damage propagation prediction results.

[0084] The pressure release module releases polishing pressure based on the obtained regional polishing pressure analysis results.

[0085] The parameters and steps of each unit module in the above-described method for precise control of the pressure zone of the polishing head in a chemical mechanical polishing device of this application can be referred to the parameters and steps in the embodiments of the above-described method for precise control of the pressure zone of the polishing head in a chemical mechanical polishing device, and will not be repeated here.

[0086] Embodiments of this application also provide an electronic device, including a memory, a processor, and a communication bus; the memory and the processor are connected via the communication bus. The memory stores a method for precise control of polishing head pressure zones in a chemical mechanical polishing apparatus, as provided in the above embodiments, which can be loaded and executed by the processor.

[0087] The memory can be used to store instructions, programs, code, code sets, or instruction sets. The memory may include a program storage area and a data storage area. The program storage area may store instructions for implementing an operating system, instructions for at least one function, and instructions for implementing the precise pressure zone control method for the polishing head of the chemical mechanical polishing equipment provided in the above embodiments; the data storage area may store data involved in the precise pressure zone control method for the polishing head of the chemical mechanical polishing equipment provided in the above embodiments.

[0088] A processor may include one or more processing cores. The processor executes instructions, programs, code sets, or instruction sets stored in memory, and calls data stored in memory to perform various functions and process data as described in this application. The processor may be at least one of a specific application-specific integrated circuit, a digital signal processor, a digital signal processing device, a programmable logic device, a field-programmable gate array, a central processing unit, a controller, a microcontroller, and a microprocessor. It is understood that, for different devices, the electronic devices used to implement the above-described processor functions may also be other types, and the embodiments of this application do not specifically limit this.

[0089] A communication bus may include a pathway for transmitting information between the aforementioned components. The communication bus can be a PCI bus or an EISA bus, etc. Communication buses can be categorized into address buses, data buses, control buses, etc.

[0090] This application provides a computer-readable storage medium storing a computer program that can be loaded by a processor and executed as described in the above embodiments, a method for precise control of polishing head pressure zoning in a chemical mechanical polishing apparatus.

[0091] In this embodiment, a computer-readable storage medium can be a tangible device that holds and stores instructions used by an instruction execution device. The computer-readable storage medium can be, but is not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof. Specifically, the computer-readable storage medium can be a portable computer disk, a hard disk, a USB flash drive, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), staging random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory stick, floppy disk, optical disk, magnetic disk, mechanical encoding device, or any combination thereof.

[0092] The term includes, or any other variation thereof, is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0093] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the foregoing application concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions claimed in this application.

Claims

1. A method for precise control of pressure zone in the polishing head of a chemical mechanical polishing device, characterized in that, The specific steps include the following: Step 1: Obtain information on the surface condition of the polishing head of the polishing equipment, the smoothness of the polishing wafer at each corresponding location, the presence of cracks, and the frictional properties. Step 2: Analyze the surface condition of the polishing head to identify any abnormalities in its operation. Analyze the abnormalities in the polishing process by examining the surface condition of the polishing head and its friction properties. The analysis of the abnormal operation of the polishing head includes the following specific steps: The first step is to acquire images of the polishing head and the operational deviation of the control commands, and to detect any abnormalities in the smoothness of the polishing head's surface or the deformation of the polishing head relative to the initial stage. The second step is to obtain the average vibration amplitude and vibration frequency of the polishing head at the corresponding rotation speed. The amplitude abnormality is obtained by dividing the average vibration amplitude by the safe amplitude, the vibration frequency abnormality is obtained by dividing the vibration frequency by the safe vibration frequency, and the vibration abnormality is obtained by multiplying the amplitude abnormality and the vibration frequency abnormality. The third step is to obtain abnormalities in the smoothness, deformation, and vibration of the polishing head, and then perform a weighted summation to obtain the abnormalities in the operation of the polishing head. The analysis of the polishing process abnormalities includes the following specific details: The first step is to obtain the calculated abnormal operation of the polishing head and the mechanical damping of the material. The mechanical damping is the loss factor or attenuation coefficient of the force transmitted inward per unit distance. The second step is to obtain the attenuation condition by multiplying the depth of the crack by the mechanical damping condition. The difference between the attenuation condition and the value of 1 is multiplied by the abnormal operation of the polishing head to obtain the abnormal impact of the polishing process on the crack. The attenuation condition is the attenuation ratio of the external vibration force transmitted to the crack location during the polishing process. Step 3: Predict the propagation of polishing damage by analyzing the smoothness of the corresponding locations on the polished wafer and the condition of surrounding cracks. The polishing damage propagation prediction includes the following specific details: The first step is to obtain the size of the crack and the smoothness of the corresponding positions on the polished wafer; the crack anomaly is obtained by dividing the crack volume by the crack safety volume, and the crack propagation prediction anomaly is obtained by multiplying the crack anomaly by the impact of the polishing process on the crack. The second step is to obtain the smoothness anomaly of the wafer by dividing the smoothness to be achieved after polishing by the smoothness of the corresponding position on the wafer. Step 4: Analyze the polishing pressure in the area based on the results of polishing process anomalies, hardness, and polishing damage propagation predictions. Step 5: Release the polishing pressure based on the obtained regional polishing pressure analysis results.

2. The method for precise control of polishing head pressure zones in a chemical mechanical polishing device according to claim 1, characterized in that, The regional polishing pressure analysis includes the following specific steps: Obtain the smoothness anomaly, hardness, and polishing head operation anomaly of the corresponding wafer; obtain the wafer hardness anomaly by dividing the wafer hardness by the safe hardness; obtain the wafer wear resistance value by taking the reciprocal of the weighted sum of the smoothness anomaly and the wafer hardness anomaly; obtain the wafer polishing anomaly by taking the weighted sum of the wafer wear resistance value and the polishing head operation anomaly. The overall polishing process anomaly is obtained by weighted summation of wafer polishing anomalies and crack propagation prediction anomalies. The safe pressure range of the polishing equipment is then obtained. The overall polishing process anomaly threshold is divided by the overall polishing process anomaly threshold to obtain the quotient. If the quotient is greater than 1, it indicates that the corresponding wafer will be damaged during polishing, and it is recommended to replace the polishing equipment. The safe pressure range of the polishing equipment is scaled proportionally to the range between 0 and 1. The quotient of the overall polishing process anomaly divided by the overall polishing process anomaly threshold is obtained. The quotient is then compared with the scaled-down result to obtain the pressure value required for polishing.

3. The method for precise control of polishing head pressure zones in a chemical mechanical polishing device according to claim 1, characterized in that, The surface condition of the polishing head includes images of the polishing head and the amplitude and frequency of vibrations generated during its operation. The images are acquired through a 3D image acquisition component and used to analyze abnormalities in the polishing head's operation. The smoothness of the polished wafer at corresponding locations is obtained from 3D images of the polished wafer surface acquired by the image acquisition module. The crack condition includes the size and depth of the acquired cracks. The friction properties include the hardness of the corresponding wafer and the mechanical damping of the material, used to analyze the damage to internal cracks of the wafer during the polishing process.

4. The method for precise control of polishing head pressure zones in a chemical mechanical polishing device according to claim 1, characterized in that, The smoothness of the polishing head is obtained by dividing the average height of each point relative to the standard surface by the safety height, and then taking the reciprocal of the quotient. The smoothness anomaly is calculated by subtracting the current smoothness from the original smoothness and dividing by the original smoothness. The deformation anomaly of the polishing head relative to the initial stage is obtained by dividing the deformation volume of the current polishing head relative to the initial stage by the volume of the polishing head in the initial stage.

5. A precise control system for pressure zoning of a polishing head in a chemical mechanical polishing (CMP) apparatus, used to implement the precise control method for pressure zoning of a polishing head in a CMP apparatus as described in any one of claims 1-4, characterized in that, Includes the following specific modules: The system includes a data acquisition module, a polishing process analysis module, a damage propagation prediction module, a polishing pressure analysis module, and a pressure release module. The data acquisition module is used to acquire information about the surface condition of the polishing head of the polishing equipment, the smoothness, crack conditions, and friction properties of the corresponding positions of the polishing wafer. The polishing process analysis module is used to analyze the abnormal operation of the polishing head by examining the surface condition of the polishing head of the polishing equipment, and to analyze the abnormal operation of the polishing head and the friction properties to analyze the abnormality of the polishing process. The damage propagation prediction module predicts the propagation of polishing damage by considering the smoothness of the polished wafer at corresponding locations and the condition of surrounding cracks. The polishing pressure analysis module performs regional polishing pressure analysis based on polishing process anomalies, hardness, and polishing damage propagation prediction results. The pressure release module releases polishing pressure based on the obtained regional polishing pressure analysis results.

6. An electronic device, comprising: A processor and a memory, wherein the memory stores a computer program that can be called by the processor; characterized in that the processor executes a method for precise control of polishing head pressure zones in a chemical mechanical polishing apparatus as described in any one of claims 1-4 by calling the computer program stored in the memory.

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