Polishing pad finishing method, device, equipment, controller and storage medium

Abstract

The invention relates to a polishing pad trimming method, device and equipment, a controller and a storage medium. According to the trimming method, an initial trimming formula is adopted when a polishing pad is trimmed in an initial trimming period, and a trimming formula adjusted through a self-learning adjustment method is adopted when the polishing pad is trimmed in a subsequent trimming period. Controllable finishing of the polishing pad is achieved through the polishing pad finishing method, the finishing parameters are adjusted and optimized according to the abrasion state of the polishing pad, the service life of the polishing pad is prolonged, and the replacement frequency and cost of the polishing pad are reduced.

Description

Technical Field

[0001] The present invention relates to the field of chemical mechanical planarization (CMP) of semiconductor wafers, and more particularly to a polishing pad conditioning method, apparatus, device, controller and storage medium of a chemical mechanical polishing device. Background Art

[0002] Integrated Circuits (ICs) are the core and lifeblood of the development of the information technology industry. Integrated Circuits are generally formed by depositing a conductive layer, a semiconductor layer or an insulating layer on a silicon wafer. As a result, a thin film formed by a filler layer is deposited on the surface of the wafer. In the manufacturing process, it is necessary to continuously flatten the filler layer until the patterned top surface is exposed to form a conductive path between the raised patterns.

[0003] Chemical Mechanical Polishing (CMP) is the preferred planarization process in the IC manufacturing process. In chemical mechanical polishing, for the manufacturing process of semiconductor devices, excessive polishing may cause damage to material properties and affect device performance; if the polishing is insufficient, additional processing steps may be required, increasing costs.

[0004] Polishing pads play a vital role in the chemical mechanical polishing process. They are responsible for storing and transporting polishing fluid, removing processing residues, transmitting mechanical loads, and maintaining the polishing environment. During the polishing process, the surface of the polishing pad will gradually wear, reducing the polishing efficiency and quality. Therefore, the polishing pad must be trimmed during use. Currently, common trimming methods include trimming with diamond dressers. Diamonds have extremely high hardness and have a good mechanical grinding effect when trimming polishing pads. However, the current trimming methods mainly rely on empirical formulas and lack a comprehensive theoretical model. They have disadvantages such as long trimming time, short polishing pad life, uneven removal efficiency, and poor accuracy. Summary of the invention

[0005] The purpose of the present invention is to provide a polishing pad dressing method, device, equipment, controller and storage medium, which utilize intelligent adjustment of dressing parameters to improve dressing accuracy and efficiency, improve the uniformity of the polishing pad and extend its service life.

[0006] In order to achieve the above object, the first aspect of the present invention provides a polishing pad conditioning method, the method comprising the following steps:

[0007] Determine the dressing cycle of the polishing pad;

[0008] The dressing formula of the polishing pad is updated once after each dressing cycle of the polishing operation performed by the polishing pad.

[0009] The initial dressing formula is used when dressing the polishing pad in the first dressing cycle, and the dressing formula adjusted by the self-learning adjustment method is used when dressing in each subsequent dressing cycle.

[0010] In the polishing pad dressing method as described above, optionally, the dressing cycle is an integer multiple of the time required to complete the polishing of each box of wafers to be polished, and the parameters of the dressing formula include the dressing time, the dressing pressure, and the movement speed of the dresser relative to the polishing pad.

[0011] In the polishing pad dressing method as described above, optionally, the self-learning adjustment method comprises the following steps:

[0012] Step I: using a topography detection component to collect current topography data of the polishing pad after trimming;

[0013] Step II: Calculate the actual dressing removal amount of the polishing pad based on the current topography data and the historical topography data of the previous cycle of the polishing pad, collect the dressing time used for the current dressing of the polishing pad, and fit the polishing pad dressing removal amount calculation formula according to the actual dressing removal amount and the dressing time;

[0014] Step III: calculating the predicted dressing removal amount of the next cycle based on the dressing removal amount calculation formula, and calculating the predicted topography data of the polishing pad after dressing in the next cycle according to the predicted dressing removal amount of the next cycle and the current topography data, and calculating the expected dressing adjustment coefficient of the dressing recipe parameters through the deviation between the predicted topography data and the target dressing topography data;

[0015] Step IV: Determine the weights of system random influence and hardware parameter influence based on historical trim adjustment coefficients, and perform weighted processing on the expected trim adjustment coefficients;

[0016] Step V: Outputting the weighted desired dressing adjustment coefficient, and outputting a new dressing recipe based on the weighted desired dressing adjustment coefficient for the polishing pad dressing of the next cycle.

[0017] In the polishing pad conditioning method as described above, optionally, steps I to V are all performed on the polishing pad in different areas.

[0018] In the polishing pad conditioning method as described above, optionally, in step I, the topography detection component collects the current topography data via a contact sensor and / or a non-contact sensor.

[0019] In the polishing pad dressing method as described above, optionally, the step of fitting the polishing pad dressing removal amount calculation formula includes:

[0020] A linear regression model y=kx+b is established, wherein y is the dressing removal amount of the polishing pad, x is the dressing time of the polishing pad, k is the dressing removal rate of the polishing pad, and b is the intercept term of the linear model;

[0021] The actual trimming removal amount y of each area of ​​the polishing pad is collected i and trim time x i ;

[0022] Define the error function, select the initial k and b values, and set the tolerance;

[0023] An iterative method is used to approximate k and b. When the value of the error function is less than or equal to the tolerance, the iteration is stopped and k and b are output.

[0024] In the polishing pad conditioning method as described above, optionally, the error function is a mean square error function:

[0025]

[0026] Here, m is the number of data points.

[0027] In the polishing pad conditioning method as described above, optionally, the iterative equation is:

[0028]

[0029] in, is the partial derivative of the error function M with respect to k, is the partial derivative of the error function with respect to b, and α is the step size, which is used to control the size of each step update.

[0030] In the polishing pad conditioning method as described above, optionally, the initial k value and b value are randomly selected values, or the initial k value and b value are calculated by the following formula:

[0031]

[0032]

[0033] Σx is all x i The sum of , Σy is all y i The sum of Σxy is the sum of all x i y i The sum of Σx 2 For all x i 2 The sum of , n is the number of areas on the polishing pad.

[0034] In order to achieve the above-mentioned purpose, the second aspect of the present invention provides a polishing pad dressing device for chemical mechanical polishing equipment, the polishing pad dressing device includes a fixed seat, a swing arm and a dresser, the dresser is connected to the fixed seat through the swing arm, the swing arm can swing around the fixed seat, and the dresser located at the end of the swing arm dresses the polishing pad by a dressing method as described in any one of the first aspects above.

[0035] In order to achieve the above-mentioned object, a third aspect of the present invention provides a chemical mechanical polishing device, wherein the chemical mechanical polishing device comprises the polishing pad conditioning device as described in the second aspect.

[0036] In order to achieve the above object, a fourth aspect of the present invention provides an intelligent controller, the intelligent controller comprising:

[0037] A memory, wherein the memory is used to store computer executable instructions or computer programs;

[0038] A processor, wherein when the processor is used to execute the computer executable instructions or computer programs stored in the memory, the processor implements the dressing method described in any one of the first aspects to dress the polishing pad used for the chemical mechanical polishing equipment.

[0039] In order to achieve the above-mentioned purpose, the fifth aspect of the present invention provides a computer-readable storage medium, which stores computer-executable instructions or computer programs. When the computer-executable instructions or computer programs are executed by the processor, the polishing pad used for the chemical mechanical polishing equipment is trimmed by the trimming method described in any one of the first aspects above.

[0040] The polishing pad dressing method, device, equipment, controller and storage medium provided by the present invention adopt an initial dressing formula when dressing the polishing pad in the first dressing cycle, and adopt a dressing formula adjusted by a self-learning adjustment method when dressing in the subsequent dressing cycle. The present invention realizes controllable dressing of the polishing pad through the polishing pad dressing method, adjusts the dressing parameters according to the wear state of the polishing pad, optimizes the dressing effect, prolongs the service life of the polishing pad, and reduces the replacement frequency and cost of the polishing pad.

[0041] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0043] Figure 1 is a flow chart of a polishing pad dressing method provided by an embodiment of the present invention;

[0044] Figure 2 is a schematic diagram of the implementation effect of the traditional trimming method provided by an embodiment of the present invention;

[0045] Figure 3 is a schematic diagram of the implementation effect of an example of a trimming method provided by an embodiment of the present invention;

[0046] Figure 4 is a schematic structural diagram of a dressing device for chemical mechanical polishing provided by an embodiment of the present invention;

[0047] Figure 5 It is a schematic diagram of the structure of the chemical mechanical polishing equipment provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in the field based on the embodiments in the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0049] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0050] The term "including" and its variations used in this document are open inclusions, i.e., "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Relevant definitions of other terms will be given in the following description.

[0051] During actual use, the polishing pad will produce wear and deformation, and the abrasive debris generated during the polishing process will fill the micropores on the surface of the polishing pad, resulting in glazing, which will reduce the ability of the polishing pad to store and transport abrasives, resulting in a decrease in material removal rate. Therefore, it is necessary to remove the glaze layer on the surface of the polishing pad and increase the surface roughness of the polishing pad. The polishing pad will also deform during use, so it is also necessary to trim the polishing pad to make it flat. Appropriate trimming can restore excessive wear and glazing on the surface of the polishing pad and extend the service life of the polishing pad. However, after trimming, the thickness of the polishing pad is reduced. Excessive trimming may cause excessive wear of the polishing pad and reduce the service life of the polishing pad. If the polishing pad wears too quickly, the loss of the polishing pad can be reduced by optimizing the parameters of the trimming formula.

[0052] Figure 1 It is a flow chart of a polishing pad dressing method provided by an embodiment of the present invention.

[0053] In this embodiment, the dressing cycle of the polishing pad is determined. According to the usage of the polishing pad and the polishing effect, a dressing formula needs to be used to dress the polishing pad, and the time interval for regularly adjusting the dressing formula is the dressing cycle. The dressing formula of the polishing pad is updated once every dressing cycle when the polishing pad performs a polishing operation.

[0054] In an optional embodiment, the frequency of polishing pad dressing within a dressing cycle may be appropriately selected according to the type of polishing pad and the polishing process requirements. For example, the polishing pad may be dressed once each time the polishing pad is used to perform a polishing operation.

[0055] In this embodiment, the dressing cycle is an integral multiple of the time taken to complete the polishing of each box of wafers to be polished. The advantage of this embodiment is that it can ensure that the polishing pad uses the same dressing formula during the polishing process of each batch of wafers, thereby maintaining a stable polishing efficiency.

[0056] In some embodiments, the parameters of the dressing formula of the polishing pad include the dressing time, the dressing pressure, and the movement speed of the dresser relative to the polishing pad. The dressing time refers to the length of time the dresser dresses the polishing pad. It is understandable that too long a dressing time may cause excessive wear of the polishing pad, and too short a dressing time may not be able to fully dress the polishing pad to achieve appropriate performance. The movement speed of the dresser relative to the polishing pad affects the uniformity and efficiency of the dressing effect. The dressing pressure is the pressure applied by the dresser to the polishing pad. Appropriate dressing pressure ensures that the surface of the polishing pad is effectively dressed. In an optional embodiment, the parameters of the dressing formula of the polishing pad may also include other parameters that affect the dressing effect of the polishing pad, such as the dressing depth and the dressing temperature.

[0057] In the polishing pad dressing method of the present invention, an initial dressing formula needs to be pre-set based on historical data and experience. The initial dressing formula refers to the dressing formula used in the initial stage of the polishing pad. The dressing parameters in the initial dressing formula, such as dressing pressure, speed, dressing time, etc., are set based on the type of polishing pad and the polishing process requirements. For more precise calculations, the surface of the polishing pad is divided into multiple areas according to the shape and size of the polishing pad, and the initial polishing parameters are set for each area.

[0058] When performing subsequent trimming, the trimming formula adjusted by the self-learning adjustment method is used, and the trimming parameters are automatically optimized through the algorithm. The self-learning adjustment method of the trimming formula includes the following steps:

[0059] Step I: using a topography detection component to collect current topography data of the polishing pad after trimming;

[0060] Step II: Calculate the actual dressing removal amount of the polishing pad based on the current topography data and the historical topography data of the previous cycle of the polishing pad, collect the dressing time used for the current dressing of the polishing pad, and fit the polishing pad dressing removal amount calculation formula according to the actual dressing removal amount and the dressing time;

[0061] Step III: Calculate the predicted dressing removal amount of the next cycle based on the dressing removal amount calculation formula, and calculate the predicted topography data of the polishing pad after dressing in the next cycle according to the predicted dressing removal amount of the next cycle and the current topography data, and calculate the expected dressing adjustment coefficient of the dressing recipe parameters through the deviation between the predicted topography data and the target topography data;

[0062] Step IV: Determine the weights of system random effects and hardware parameter effects based on historical trim adjustment coefficients, and perform weighted processing on the expected trim adjustment coefficients;

[0063] Step V: Outputting the weighted expected dressing adjustment coefficient, and outputting a new dressing recipe based on the weighted expected dressing adjustment coefficient for the polishing pad dressing of the next cycle.

[0064] In step I, the topography data of the polishing pad refers to the profile of the polishing pad, that is, the collection of height information of each area on the surface of the polishing pad. In different embodiments, the topography detection component can be a contact sensor, which measures the surface topography of the polishing pad by directly contacting the polishing pad. Other detection devices such as non-contact sensors such as acoustic sensors and optical sensors all fall within the scope of protection of the present invention. In some embodiments, a contact sensor can be used to measure the roughness and pressure distribution of the polishing pad, while a non-contact sensor can also be used to measure the surface profile and thickness of the polishing pad. In an optional embodiment, the topography of the polishing pad can be obtained by a sensor abutting the surface of the polishing pad and following the ups and downs of the polishing pad by measuring the distance between the sensor and the polishing disk below the polishing pad.

[0065] In step II, the actual removal amount of the polishing pad is the amount of material removed from the polishing pad during the polishing process. The value of the actual removal amount of the polishing pad is calculated based on the difference between the current morphological data of the polishing pad and the morphological data of the previous cycle of the polishing pad.

[0066] In an optional embodiment, the calculation formula for fitting the dressing removal amount of the polishing pad may include:

[0067] A linear regression model y=kx+b is established, where y is the dressing removal amount of the polishing pad, x is the dressing time of the polishing pad, k is the dressing removal rate of the polishing pad, and b is the intercept term of the linear model. Then, the actual dressing removal amount y of the data points in each area of ​​the polishing pad is collected. i and trim time x i The linear regression model assumes that there is a linear relationship between the polishing pad dressing removal amount y and the polishing pad dressing time x. By finding the optimal k value and b value, the difference between the polishing pad dressing removal amount predicted by the model and the actual polishing pad dressing removal amount is minimized. By establishing a linear regression model, the best match for the function of the dressing removal amount of each area of ​​the polishing pad is found, so that the data points of each area of ​​the polishing pad are as close as possible to the dressing removal calculation formula of each area. In optional embodiments, other linear or nonlinear regression models can also be used.

[0068] In an optional embodiment, an error function is defined to measure the difference between the predicted polishing pad dressing removal amount and the actual polishing pad dressing removal amount, and the initial k value and b value are selected, and the tolerance is set. It can be understood that the tolerance is the maximum error range that the model can accept.

[0069] In some embodiments, the error function may be an average error function, the equation of which is:

[0070]

[0071] Here, m is the number of data points.

[0072] It can be understood that the mean error function can be used to evaluate the accuracy of model prediction. During the model training process, the mean square error function can be used as a loss function to adjust the model parameters and improve the model's prediction performance by minimizing the value of the mean error function.

[0073] In some optional embodiments, an iterative method may be used to approximate k and b, and when the value of the error function is less than or equal to the tolerance, the iteration is stopped. In some embodiments, the iterative equations of k and b are:

[0074]

[0075] in, is the partial derivative of the error function M with respect to k, is the partial derivative of the error function with respect to b, and α is the step size, which is used to control the size of each step update.

[0076] In some examples, the tolerance is usually set to a small value to ensure that the model can find the most suitable solution during the iteration process.

[0077] In an optional embodiment, the initial k value and b value may be random values ​​or estimated values.

[0078] As a feasible implementation method, the initial k value and b value can be calculated by the least squares method, where

[0079] The calculation equation for k is:

[0080]

[0081] The calculation equation for b is:

[0082]

[0083] Where Σx is all x i The sum of , Σy is all y i The sum of Σxy is the sum of all x i y i The sum of Σx 2 For all x i 2 The sum of , n is the number of data points in the dataset.

[0084] It can be understood that estimating the initial k value and b value by the least squares method helps the above iterative algorithm converge to the optimal solution more quickly.

[0085] In step III, the predicted trimming removal amount of the next cycle is calculated according to the trimming removal amount calculation formula. According to the predicted trimming removal amount of the next cycle and the current morphology data, the predicted morphology data of the polishing pad after trimming in the next cycle can be preliminarily calculated. By comparing the predicted morphology data with the target trimming morphology data, the deviation, that is, the expected trimming removal amount of the polishing pad in the next cycle, is calculated. The expected trimming adjustment coefficient of the trimming formula parameters is calculated by the expected trimming removal amount of the polishing pad in the next cycle. The trimming adjustment coefficient is used to modify the coefficient corresponding to each parameter in the trimming formula, such as the trimming time, the trimming pressure, and the movement speed of the dresser relative to the polishing pad. Adjusting the trimming adjustment coefficient refers to adjusting the coefficient of modification of each parameter. The trimming adjustment coefficient will be affected by many factors, such as hardware parameters and random effects of the system. These factors that will affect the accuracy of the trimming adjustment coefficient are analyzed, and the trimming adjustment coefficient is adjusted by adjusting the weights of these factors to achieve the expected trimming effect.

[0086] In step IV, hardware parameters, such as hardness, elasticity and particle size of the polishing pad, will have an impact on the dressing process of the polishing pad. By adjusting the desired dressing adjustment coefficient in a weighted manner, the accuracy of the model can be improved.

[0087] It can be understood that the random effects of the system are caused by a variety of unpredictable reasons, such as temperature changes, material non-uniformity and random jitter of the system. This random effect may affect the accuracy of the data. By adjusting the weight of the random effects of the system, the expected dressing adjustment coefficient of the polishing pad is optimized.

[0088] In an optional embodiment, the desired trimming adjustment coefficient can be adjusted more accurately by comparing the trimming adjustment coefficients in several recent trimming processes, and the influence of abnormal values ​​can be reduced by analyzing similar data points.

[0089] In step V, a new dressing recipe is formulated according to the weighted desired dressing adjustment coefficient of the polishing pad, and the new dressing recipe is implemented in the dressing of the polishing pad in the next cycle.

[0090] Figure 2 and Figure 3 It is a schematic diagram of the effects of a conventional dressing method and an example of a polishing pad dressing method provided by an embodiment of the present invention.

[0091] exist Figure 2 and Figure 3 In the figure, the horizontal axis represents the radius of the polishing pad, in units of inches, i.e., inches; the vertical axis represents the groove depth of the polishing pad, in units of millimeter, i.e., one thousandth of an inch. The trend lines in the figure show the different dressing effects of the polishing pad in the conventional dressing method and the polishing pad dressing method provided by the present invention. The different trend lines are marked as 0H, 5H, 10H, 15H, and 20H, in units of hours, representing hours, indicating the time period during the polishing pad dressing process. Figure 2 and / or Figure 3 It can be seen that during the dressing process of the polishing pad, as time goes by, the dressing effect of the polishing pad becomes worse and the trend line becomes more unstable.

[0092] like Figure 2 and Figure 3 As shown, compared with the traditional dressing method, the polishing pad dressing method provided by the present invention has a smoother trend line, which may mean that the polishing pad dressing method provided by the present invention adjusts the dressing formula to make the polishing pad more flat, which can enable the polishing pad to maintain better uniformity during dressing and improve the stability and repeatability of the dressing process.

[0093] Figure 4 It is a schematic diagram of the structure of a dressing device for chemical mechanical polishing provided by an embodiment of the present invention.

[0094] like Figure 4 As shown, the dressing device 100 includes a fixed seat 101, a swing arm 102, and a dresser 103. The dresser 103 includes a dressing head 104 and a morphology detection device (not shown in the figure). In an optional embodiment, the bottom of the dresser 103 is inlaid with diamonds, and the diamonds have high hardness and corrosion resistance. The dressing head 104 reciprocates on the surface of the polishing pad, and the diamond particles cut and dress the polishing pad. The morphology detection device can measure the morphology of the polishing pad. In an optional embodiment, the type of the morphology detection device is not limited, for example, non-contact sensors such as eddy current sensors and contact sensors such as contact displacement sensors all fall within the protection scope of the present invention. In some embodiments, the morphology detection device and the dressing head 104 are arranged adjacent to each other in the horizontal direction. The advantage of this arrangement is that it can avoid the dressing head 104 interfering with the measurement of the morphology detection device during the process of dressing the polishing pad.

[0095] In an optional embodiment, the dresser 103 is connected to the fixed seat 101 through the swing arm 102. The dresser 103 located at the end of the swing arm 102 can perform reciprocating motion to dress the polishing pad by swinging the swing arm 102 around the fixed seat 101.

[0096] Figure 5 It is a schematic diagram of the structure of the chemical mechanical polishing equipment provided in an embodiment of the present invention.

[0097] Figure 5 In the present invention, the chemical mechanical polishing device includes a dressing device 100, and the structure of the dressing device 100 is as follows: Figure 4 shown. Figure 5 In the illustrated embodiment, the chemical mechanical polishing apparatus further includes a polishing plate 200, a carrier head 300, and a liquid supply device 400. Figure 5 In the example, the polishing disc 200 covers the polishing pad to be used for polishing the wafer, the carrier head 300 presses the wafer against the polishing pad on the polishing disc 200, and the liquid supply device 400 sprays the polishing liquid onto the surface of the polishing pad. Under the chemical action of the polishing liquid, the wafer and the polishing pad are rubbed against each other through the relative movement of the carrier head 300 and the polishing disc 200, thereby polishing. During the polishing process, the trimming device 100 trims the polishing pad. Specifically, the trimming device 100 can trim the surface deformation of the polishing pad generated during the polishing process of the wafer, so that the morphology of the polishing pad meets the process requirements, thereby stabilizing the polishing removal rate of the wafer, achieving global flattening of the wafer, and extending the service life of the polishing pad.

[0098] The present invention also provides an intelligent controller, including a memory and a processor. The memory is used to store computer executable instructions or computer programs. When the processor is used to execute the computer executable instructions or computer programs stored in the memory, the dressing method in any of the above embodiments is implemented to dress the polishing pad of the chemical mechanical polishing device.

[0099] Furthermore, the present invention also provides a computer-readable storage medium, which stores computer-executable instructions or a computer program. When the computer-executable instructions or the computer program are executed by a processor, the dressing method in any of the aforementioned embodiments is implemented for dressing the polishing pad of a chemical mechanical polishing device.

[0100] It should be noted that the computer-readable storage medium of the present invention may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, device, or component.

[0101] The above implementation methods are only used to illustrate the embodiments of the present invention, and are not limitations of the embodiments of the present invention. Ordinary technicians in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present invention. The patent protection scope of the embodiments of the present invention should be defined by the claims.

Claims

1. A polishing pad dressing method, characterized in that: The method comprises the following steps: Determine the dressing cycle of the polishing pad; The dressing formula of the polishing pad is updated once after each dressing cycle of the polishing operation performed by the polishing pad. The initial dressing formula is used when dressing the polishing pad in the first dressing cycle, and the dressing formula adjusted by the self-learning adjustment method is used when dressing in each subsequent dressing cycle.

2. The polishing pad conditioning method according to claim 1, wherein: The dressing cycle is an integer multiple of the time taken to complete the polishing of each box of wafers to be polished, and the parameters of the dressing formula include the dressing time, the dressing pressure, and the movement speed of the dresser relative to the polishing pad.

3. The polishing pad conditioning method according to claim 1, wherein: The self-learning adjustment method comprises the following steps: Step I: using a topography detection component to collect current topography data of the polishing pad after trimming; Step II: Calculate the actual dressing removal amount of the polishing pad based on the current topography data and the historical topography data of the previous cycle of the polishing pad, collect the dressing time used for the current dressing of the polishing pad, and fit the polishing pad dressing removal amount calculation formula according to the actual dressing removal amount and the dressing time; Step III: calculating the predicted dressing removal amount of the next cycle based on the dressing removal amount calculation formula, and calculating the predicted topography data of the polishing pad after dressing in the next cycle according to the predicted dressing removal amount of the next cycle and the current topography data, and calculating the expected dressing adjustment coefficient of the dressing recipe parameters through the deviation between the predicted topography data and the target dressing topography data; Step IV: Determine the weights of system random influence and hardware parameter influence based on historical trim adjustment coefficients, and perform weighted processing on the expected trim adjustment coefficients; Step V: Outputting the weighted desired dressing adjustment coefficient, and outputting a new dressing recipe for polishing pad dressing in the next cycle based on the weighted desired dressing adjustment coefficient.

4. The polishing pad conditioning method according to claim 3, wherein: The steps I to V are all performed on the polishing pad in different areas.

5. The polishing pad conditioning method according to claim 4, wherein: In the step I, the shape detection component collects the current shape data through a contact sensor and / or a non-contact sensor.

6. The polishing pad conditioning method according to claim 4, wherein: The step of fitting the polishing pad dressing removal amount calculation formula comprises: A linear regression model y=kx+b is established, wherein y is the dressing removal amount of the polishing pad, x is the dressing time of the polishing pad, k is the dressing removal rate of the polishing pad, and b is the intercept term of the linear model; The actual trimming removal amount y of each area of ​​the polishing pad is collected i and trim time x i ; Define the error function, select the initial k and b values, and set the tolerance; An iterative method is used to approximate k and b. When the value of the error function is less than or equal to the tolerance, the iteration is stopped and k and b are output.

7. The polishing pad conditioning method according to claim 6, wherein: The error function is the mean square error function: Here, m is the number of data points.

8. The polishing pad conditioning method according to claim 6, wherein: The iterative equation is: in, is the partial derivative of the error function M with respect to k, is the partial derivative of the error function with respect to b, and α is the step size, which is used to control the size of each step update.

9. The polishing pad conditioning method according to claim 6, wherein: The initial k value and b value are randomly selected values, or the initial k value and b value are calculated by the following formula: ∑x is all x i The sum of ∑y is the sum of all y i The sum of ∑xy is the sum of all x i y i The sum of ∑x 2 For all x i 2 The sum of , n is the number of areas on the polishing pad.

10. A polishing pad dressing device for chemical mechanical polishing equipment, characterized in that: The polishing pad dressing device includes a fixed seat, a swing arm and a dresser, wherein the dresser is connected to the fixed seat via the swing arm, and the swing arm can swing around the fixed seat. The dresser located at the end of the swing arm uses the dressing method described in any one of claims 1 to 9 to dress the polishing pad.

11. A chemical mechanical polishing device, characterized in that: The chemical mechanical polishing equipment comprises the polishing pad conditioning device according to claim 10 .

12. An intelligent controller, characterized in that: The intelligent controller comprises: A memory, wherein the memory is used to store computer executable instructions or computer programs; A processor, wherein when the processor is used to execute the computer executable instructions or computer programs stored in the memory, the processor implements the dressing method according to any one of claims 1 to 9 to dress the polishing pad used for the chemical mechanical polishing device.

13. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions or a computer program. When the computer-executable instructions or the computer program are executed by a processor, the dressing method according to any one of claims 1 to 9 is implemented to dress the polishing pad used for the chemical mechanical polishing device.

Images