Control method and system for maintaining dynamic stability of concentration of electroplating solution, electronic equipment and readable storage medium

Abstract

The invention provides a control method and system for maintaining dynamic stability of the concentration of electroplating liquid, electronic equipment and a readable storage medium. The control method comprises the steps that the working state of an electroplating cavity is monitored in real time; calculating the metal salt concentration loss based on the working state of the electroplating cavity, calculating a first water supplementing amount based on the evaporation amount of the electroplating cavity and / or the liquid storage tank when the electroplating cavity does not execute the wafer electroplating process, and calculating a second water supplementing amount based on the evaporation amount of the electroplating cavity and / or the liquid storage tank when the electroplating cavity executes the wafer electroplating process; and calculating a second water supplementing amount and a metal ion supplementing preset amount based on the metal ion consumption amount of the wafer electroplating process and the evaporation amounts of the liquid storage tank and the electroplating cavity. Different water supplementing and metal salt supplementing strategies can be designed according to different working states of the electroplating cavity, and the water supplementing and metal salt supplementing precision is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of electroplating solution concentration control, and relates to a control method, system, electronic device, and readable storage medium for maintaining dynamic stability of electroplating solution concentration. Background Art

[0002] In electroplating processes, especially alloy electroplating processes, maintaining a stable metal ion concentration in the plating solution is crucial for ensuring plating quality. In related technologies, the primary factors influencing metal ion concentration in the plating solution are water evaporation and ion consumption. Therefore, to maintain a stable metal ion concentration in the plating solution, the primary measure currently employed is to regularly replenish water and metal salts.

[0003] Although the concentration of metal ions in the electroplating solution can be maintained to a certain extent by regularly replenishing water and metal salts in the related art, the strategy for replenishing water and metal salts is relatively simple and cannot be flexibly replenished according to different operating states and process conditions of the equipment, resulting in insufficient accuracy in replenishing water and metal salts. Summary of the Invention

[0004] The purpose of this application is to provide a control method, system, electronic device and readable storage medium for maintaining the dynamic stability of the plating solution concentration. The method can design different water replenishment and metal salt replenishment strategies according to the different working conditions of the plating chamber, dynamically adjust the changes in metal salt concentration, and improve the accuracy of water replenishment and metal salt replenishment.

[0005] In a first aspect of an embodiment of the present application, the present application provides a control method for maintaining dynamic stability of electroplating solution concentration, the control method being applied to an electroplating system, the electroplating system comprising an electroplating chamber and a liquid storage tank, the control method comprising:

[0006] Real-time monitoring of the working status of the electroplating chamber;

[0007] Calculating the metal salt concentration loss based on the working state of the electroplating chamber, wherein, when the electroplating chamber is not performing a wafer electroplating process, a first water replenishment amount is calculated based on the evaporation amount of the electroplating chamber and / or the liquid reservoir; and when the electroplating chamber is performing a wafer electroplating process, a second water replenishment amount and a preset metal ion replenishment amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the electroplating chamber;

[0008] The metal salt concentration of the electroplating solution is dynamically adjusted based on the metal salt concentration loss to correct the metal salt concentration loss.

[0009] In one embodiment, when the plating chamber is not performing a wafer electroplating process, calculating the first water replenishment amount based on the evaporation amount of the plating chamber and / or the liquid storage tank includes:

[0010] Calculate the first average evaporation amount of the electroplating solution in the liquid storage tank per unit time;

[0011] A first water replenishment amount of the electroplating solution is calculated according to a preset water replenishment interval and the first average evaporation amount.

[0012] In one embodiment, when the plating chamber is not performing a wafer electroplating process, calculating the first water replenishment amount based on the evaporation amount of the plating chamber and / or the liquid storage tank further includes:

[0013] Calculating a first average evaporation amount of the electroplating solution in the liquid storage tank per unit time and a second average evaporation amount of the electroplating solution in a single electroplating chamber per unit time;

[0014] A second water replenishment amount required for the electroplating solution per unit time is calculated based on the first average evaporation amount, the second average evaporation amount, and the number of the electroplating chambers.

[0015] In one embodiment, when the electroplating chamber is performing a wafer electroplating process, calculating the second water replenishment amount and the preset metal ion replenishment amount based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the electroplating chamber includes:

[0016] Calculate the amount of metal ions required for electroplating a single wafer based on the wafer's surface area and process fill thickness;

[0017] Calculate the amount of metal ions required for electroplating multiple wafers based on the amount of metal ions required for electroplating a single wafer.

[0018] A preset replenishment amount of metal ions is obtained according to the amount of metal ions consumed during electroplating of the plurality of wafers.

[0019] In one embodiment, when the electroplating chamber is performing a wafer electroplating process, the second water replenishment amount and the preset metal ion replenishment amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the electroplating chamber, and further includes:

[0020] Calculating a first average evaporation amount of the plating solution in the liquid storage tank per unit time and a second average evaporation amount of the plating solution in a single plating chamber per unit time;

[0021] The second water replenishment amount required for the plating solution per unit time is calculated based on the first average evaporation amount, the second average evaporation amount, the number of plating chambers, the number of wafers, the water flow rate of the cleaned wafers returning to the plating chamber, and the amount of water consumed by the dissolution of the metal salt.

[0022] In one embodiment, the calculating of a first average evaporation amount of the electroplating solution in the liquid storage tank per unit time includes:

[0023] Calibrate and record the initial liquid level L0 of the electroplating solution in the reservoir or the initial weight W0 of the reservoir;

[0024] The liquid level of the electroplating solution or the weight of the liquid storage tank is measured once every time interval Δt. The total time required after N measurements is Ttotal and the measured liquid level of the electroplating solution is L N The measured weight of the liquid storage tank is W N ;

[0025] According to the initial weight W0 of the liquid storage tank and the weight W after N measurements N and the total time Ttotal, calculate the first average evaporation amount of the liquid storage tank in unit time or the initial liquid level L0 of the plating solution and the liquid level L after N measurements of the plating solution N The first average evaporation amount of the liquid storage tank per unit time is calculated based on the total time Ttotal.

[0026] In a second aspect of an embodiment of the present application, a control system for maintaining dynamic stability of plating solution concentration is applied to the above-mentioned control method for maintaining dynamic stability of plating solution concentration, comprising:

[0027] A monitoring unit, used to monitor the working status of the electroplating chamber and the changes in the metal salt concentration of the electroplating solution in real time;

[0028] a calculation unit connected to the monitoring unit, and configured to calculate a metal salt concentration loss based on an operating state of the electroplating chamber, wherein, when the electroplating chamber is not performing a wafer electroplating process, a first water replenishment amount is calculated based on an evaporation amount of the electroplating chamber and / or the liquid reservoir; and when the electroplating chamber is performing a wafer electroplating process, a second water replenishment amount and a preset metal ion replenishment amount are calculated based on metal ion consumption in the wafer electroplating process, evaporation amount of the liquid reservoir and the electroplating chamber;

[0029] A correction unit is connected to the calculation unit and is used to dynamically adjust the metal salt concentration of the electroplating solution based on the metal salt concentration loss to correct the metal salt concentration loss.

[0030] According to a third aspect of an embodiment of the present application, an electronic device includes a memory and a processor, wherein the memory stores a program for running on the processor, and when the program is executed by the processor, the electronic device implements the above method.

[0031] In a fourth aspect of the embodiments of the present application, a readable storage medium is provided, wherein a program is stored in the readable storage medium, and when the program is executed, the above-mentioned method is implemented.

[0032] In a fifth aspect of an embodiment of the present application, a computer program product is provided, which can be directly loaded into a data storage device of a computing unit of a control system for maintaining the dynamic stability of the concentration of a plating solution. The computer program product has a program code mechanism so that when the computer program product is executed in the control system for maintaining the dynamic stability of the concentration of a plating solution, a control method for maintaining the dynamic stability of the concentration of a plating solution is executed.

[0033] Beneficial effect: Since the present application monitors the working status of the electroplating chamber in real time; and calculates the metal salt concentration loss based on the working status of the electroplating chamber, wherein, when the electroplating chamber is not performing the wafer electroplating process, the first water replenishment amount is calculated based on the evaporation amount of the electroplating chamber and / or the liquid storage tank; when the electroplating chamber performs the wafer electroplating process, the second water replenishment amount and the metal ion replenishment preset amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid storage tank and the electroplating chamber. Therefore, the present application can design different water replenishment and metal salt replenishment strategies for different working operating states of the electroplating chamber, dynamically adjust the change in metal salt concentration, improve the accuracy of water replenishment and metal salt replenishment, and avoid the difficulty of a single water and metal salt replenishment model to cope with the concentration change requirements of the plating solution under different working states of the electroplating chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A flow chart of a control method for maintaining dynamic stability of electroplating solution concentration provided by an exemplary embodiment of the present application;

[0035] Figure 2 A flowchart of an exemplary method when the plating chamber provided in an embodiment of the present application is not performing a wafer electroplating process;

[0036] Figure 3 Another exemplary method flow chart of an embodiment of the present invention when the plating chamber does not perform a wafer electroplating process;

[0037] Figure 4 A flowchart of an exemplary method for performing a wafer electroplating process in an electroplating chamber provided in an embodiment of the present application;

[0038] Figure 5 A flowchart of an exemplary method for performing a wafer electroplating process in an electroplating chamber provided in an embodiment of the present application;

[0039] Figure 6 A structural diagram of a control system for maintaining dynamic stability of electroplating solution concentration provided by an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0040] The following describes the embodiments of the present application through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0041] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0042] In the related technology, in addition to the main technical problems existing in the background technology, there is also a secondary technical problem, that is, the single strategy of replenishing water and metal salts is also difficult to cope with the interference of multiple factors such as the evaporation rate of the plating solution in multiple plating chambers, the consumption of metal salts, and the flow rate of water returning to the plating chamber after cleaning the wafer surface. This can easily cause the concentration of the plating solution to deviate from the process window, thereby reducing the plating quality of the wafer.

[0043] Therefore, in order to solve the above-mentioned technical problems, the present application provides a control method, system, electronic device and readable storage medium for maintaining the dynamic stability of the plating solution concentration, which can design different water replenishment and metal salt replenishment strategies for different working states of the plating chamber, dynamically adjust the water replenishment and metal salt replenishment strategies of the plating solution, improve the accuracy of water replenishment and metal salt replenishment, and avoid the problem that the single water and metal salt replenishment model is difficult to cope with the changing requirements of the plating solution concentration under different working states of the plating chamber.

[0044] like Figure 1 As shown, an exemplary embodiment of the present application provides a control method for maintaining dynamic stability of the concentration of a plating solution. The control method is applied to an electroplating system, wherein the electroplating system includes a plating chamber and a liquid reservoir. The liquid reservoir is connected to the plating chamber via a pump body. The liquid reservoir is used to store the plating solution. The plating chamber is used to perform a wafer electroplating process. The control method includes:

[0045] S100: Real-time monitoring of the working status of the electroplating chamber.

[0046] Among them, the working status of the electroplating chamber includes the electroplating chamber not performing the wafer electroplating process and the electroplating chamber performing the electroplating process. When the electroplating chamber does not perform the wafer electroplating process, it can also be divided into the electroplating chamber being offline and the electroplating chamber being connected to the production line.

[0047] S200: Based on the working status of the electroplating chamber, the metal salt concentration loss is calculated, wherein, when the electroplating chamber is not performing the wafer electroplating process, the first water replenishment amount is calculated based on the evaporation amount of the electroplating chamber and / or the liquid storage tank; when the electroplating chamber is performing the wafer electroplating process, the second water replenishment amount and the metal ion replenishment preset amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid storage tank and the electroplating chamber.

[0048] In this embodiment, when the plating chamber is not performing the wafer electroplating process, it can be divided into the plating chamber being in an offline state and the plating chamber being connected to the production line. When the plating chamber is in an offline state, all the plating liquid flows back to the liquid storage tank for self-circulation, and the plating chamber is not involved in the change of the plating liquid concentration. Therefore, when dynamically adjusting the metal salt concentration, it is only necessary to adjust the plating liquid concentration in the liquid storage tank. Because the wafer is not undergoing the electroplating process at this time, the metal salt concentration loss of the plating solution only involves the water evaporated by the self-circulation of the liquid storage tank. Therefore, when the plating chamber is in an offline state, it is only necessary to replenish the plating solution with corresponding water capacity according to the water evaporated by the self-circulation of the liquid storage tank.

[0049] In this embodiment, when the plating chamber is connected to the production line but the wafer electroplating process is not performed, the plating solution circulates between the liquid reservoir and the plating chamber. When dynamically adjusting the metal salt concentration, it is necessary to consider the evaporation of water in the liquid reservoir and the plating chamber. However, since the wafer is not undergoing the electroplating process at this time, the loss of metal salt concentration in the plating solution only involves the water evaporated from the liquid reservoir and the plating chamber. Therefore, when the plating chamber is connected to the production line but the wafer electroplating process is not performed, it is only necessary to replenish the plating solution with corresponding water capacity according to the water evaporated from the liquid reservoir and the plating chamber.

[0050] In this embodiment, when the plating chamber performs a wafer electroplating process, the wafers participate in the electroplating process and consume metal ions. Therefore, when the plating chamber performs the wafer electroplating process, it is necessary to consider the consumption of metal ions involved in the wafer electroplating process, the evaporation rate of the liquid reservoir, and the plating chamber to adjust the plating solution's water capacity and metal salt replenishment accordingly. In this embodiment, the metal ions may be gold ions and silver ions.

[0051] In summary, the present application can design different water replenishment and metal salt replenishment strategies according to the different working conditions of the electroplating chamber, dynamically adjust the changes in metal salt concentration, improve the accuracy of water replenishment and metal salt replenishment, and avoid the problem that the single water and metal salt replenishment model is difficult to cope with the changes in plating solution concentration under different working conditions of the electroplating chamber.

[0052] In an exemplary embodiment, Figure 2 As shown, when the plating chamber is not performing a wafer electroplating process, the first water replenishment amount is calculated based on the evaporation amount of the plating chamber and / or the liquid storage tank, including:

[0053] S210: Calculate the first average evaporation amount Q of the plating solution in the storage tank per unit time t1 .

[0054] In a possible embodiment, the method for calculating the first average evaporation amount of the electroplating solution in the liquid storage tank per unit time includes: recording the initial weight W0 of the liquid storage tank.

[0055] The weight of the liquid reservoir is measured once every time interval Δt (Δt can be set to 1-60 minutes). The total time required after N measurements is Ttotal and the measured weight of the liquid reservoir is W. N Different reservoir materials and environmental conditions may result in different evaporation rates. Set the interval to 1-60 minutes. For evaporation processes with large fluctuations over a short period of time, set the interval to 1 minute. Shorter intervals allow for more frequent data collection, thereby more accurately capturing changes in evaporation and more accurately reflecting average evaporation. For scenarios with less demanding data accuracy, set the interval to 60 minutes. Setting the interval Δt to 1-60 minutes ensures experimental data accuracy while also taking into account operational feasibility and data processing efficiency.

[0056] According to the initial weight W0 of the liquid storage tank and the weight W after N measurements N And the total time Ttotal calculates the first average evaporation amount Q per unit time of the storage tank s t1 , the calculation formula is: Q t1 =(W0-W N ) / Ttotal, where W0 is the initial weight of the reservoir, W N is the weight of the liquid reservoir after N measurements, and Ttotal is the total time required after N measurements.

[0057] In one possible embodiment, when the liquid reservoir is offline and the plating solution has completely returned to the reservoir, a first average evaporation amount per unit time of the liquid reservoir is calculated. The method for calculating the first average evaporation amount per unit time of the liquid reservoir includes recording an initial liquid level L0 of the plating solution in the liquid reservoir.

[0058] The liquid level of the plating solution is measured once every time interval Δt. The total time required after N measurements is Ttotal and the measured liquid level of the plating solution is L N ;

[0059] According to the initial liquid level L0 of the electroplating solution and the liquid level L after N measurements N And the total time Ttotal calculates the first average evaporation amount Q per unit time of the liquid storage tank t1 , the calculation formula is: Q t1 =(L0-L N)*S / Ttotal, where S is the cross-sectional area of the reservoir, L0 is the initial liquid level of the plating solution, and L N is the liquid level after N measurements, and Ttotal is the total time required after N measurements.

[0060] In a possible embodiment, the cross-sectional area S of the liquid storage tank is obtained by directly measuring the geometric dimensions of the liquid storage tank, or is determined by calibrating a liquid level-volume relationship curve.

[0061] In a possible embodiment, the present application can also calibrate the average evaporation amount per hour of the liquid storage tank through experiments. If the environmental conditions or process parameters change significantly (such as temperature fluctuation of ±5°C), the first average evaporation amount needs to be recalibrated.

[0062] S220: According to the preset water replenishment interval T1 and the first average evaporation amount Q t1 , calculate the first water replenishment amount Q1 of the plating solution; the specific calculation formula is: Q1=Q t1 *T1, where Q t1 is the first average evaporation, T1 is the water replenishment interval. t1 =50ml / h, the water replenishment interval is 4h, then the water replenishment amount each time is 200ml.

[0063] The preset rehydration interval of the present application is determined according to the requirements of the electroplating process. For example, if the offline rehydration interval is too long, rehydration is performed every two days, which may cause the grain size of the metal coating deposited during the electroplating process to increase, resulting in the phenomenon of roughening the microstructure of the coating surface, thereby reducing the density and uniformity of the coating. If the rehydration interval is shortened to 8 hours or less (usually set to 4-8 hours), the grain size of the metal coating deposited on the surface of the wafer is significantly reduced by high-frequency rehydration, and the grain distribution is more uniform and dense. The refined coating has higher surface smoothness, mechanical strength and functional performance. The present application can also set the rehydration interval for different electroplating process requirements based on the experience that the historical rehydration interval may be too long or too short, resulting in additive loss of control, cost increase and coating defects, so as to maintain the concentration of the plating solution stable, thereby making the metal coating on the surface of the wafer more uniform and smoother during wafer electroplating.

[0064] In this embodiment, since no wafer electroplating process is performed when the plating chamber is offline, meaning no metal ions (in this embodiment, the metal ions specifically refer to gold and silver ions) are consumed, there is no need to replenish silver and gold salts. This embodiment only requires calculating the first average evaporation rate of the plating solution in the reservoir per unit time by weighing the reservoir and calibrating the liquid level gauge, thereby obtaining the first replenishment volume Q1 required when the plating chamber is not connected to the production line. This prevents significant concentration variations in the reservoir, improving system reliability. Furthermore, regular offline calibration simplifies maintenance complexity and functional loss during long-term system operation.

[0065] In another exemplary embodiment, Figure 3 As shown, when the plating chamber is not performing a wafer electroplating process, calculating the first water replenishment amount based on the evaporation amount of the plating chamber and / or the liquid storage tank further includes:

[0066] S310: Calculate the first average evaporation amount Q of the plating solution in the liquid storage tank per unit time t1 And the second average evaporation amount Q of the plating solution in a single plating chamber per unit time t2 ;

[0067] The first average evaporation amount Q in this embodiment t1 The calculation of is the same as that of the above step S210. For details, please refer to the above step S210 and will not be described in detail here.

[0068] In a possible embodiment, the calculation formula for calculating the second average evaporation amount per unit time in a single electroplating chamber is: Q t2 =(M0-M t ) / t, where Q t2 The second average evaporation amount per unit time of a single electroplating chamber (g / m 2 h), M0, M t are the mass of solution (g) at the initial time and time t, respectively.

[0069] In a possible embodiment, the calculation formula for calculating the second average evaporation amount per unit time in a single electroplating chamber is: Q t2 =(L0-L t )*S / t, where Q t2 The second average evaporation amount per unit time of a single electroplating chamber (g / m 2 h), L0, L t are the solution levels (g) at the initial and time t, respectively, and S is the cross-sectional area of the plating solution.

[0070] S320: Based on the first average evaporation amount Q t1 , the second average evaporation Q t2And the number of plating chambers n, calculate the first water replenishment volume Q2 required for the plating solution per unit time, the specific calculation formula is: Q2 = Q t1 +Q t2 *n, where n is the number of plating chambers connected to the production line, Q t1 Q is the first average evaporation amount per unit time of the liquid storage tank, t2 It is the second average evaporation amount per unit time in a single plating chamber.

[0071] In one possible embodiment, if the system has 5 electroplating chambers, 3 of which are in an online circulation state (regardless of whether they are in production), if the first average evaporation amount of the liquid storage tank per unit time is 50 ml, and the second average evaporation amount of a single electroplating chamber per unit time is 20 ml, then the first water replenishment amount required for the electroplating solution per unit time is 50+20*3=110 ml.

[0072] Example: If a machine has 5 chambers, 2 of which are offline for maintenance and 3 remain online, then n = 3; if all chambers are online but not producing, then n equals the total number of chambers.

[0073] This application avoids ineffective water replenishment of offline chambers by distinguishing the number of online chambers, thereby improving resource utilization; this application adapts to the complex working conditions of multiple electroplating chamber systems, ensuring that the calculated water replenishment amount strictly matches the actual evaporation amount.

[0074] Although the plating chamber of the present application has been connected to the production line, since the plating chamber does not perform an electroplating process and the metal ions are not consumed, there is no need to replenish metal salts (the metal salts in the present application specifically refer to gold salts and silver salts). Therefore, the present application only needs to calculate the first average evaporation amount of the plating solution in the liquid storage tank per unit time, the second average evaporation amount of a single plating chamber per unit time, and the number of plating chambers to calculate the first water replenishment amount required for the plating solution per unit time, thereby preventing the plating solution from experiencing large concentration changes and improving the accuracy of the plating solution.

[0075] In another exemplary embodiment, Figure 4 As shown, when the plating chamber performs a wafer electroplating process, the second water replenishment amount and the metal ion replenishment preset amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the plating chamber, including:

[0076] S410: Calculating the amount of metal ions consumed when electroplating a single wafer based on the surface area and process fill thickness of the wafer.

[0077] In one possible embodiment, if the surface area A (unit: dm 2) and process filling thickness Z (unit: μm), the gold consumption can be directly calculated: Gold consumption (g) = 0.049*A*Z, where 0.049 is the conversion factor. 3 ) and Faraday's law. For example: the surface area of the wafer is A = 50mm 2 =0.005dm 2 , the electroplating filling thickness Z = 3μm, then the consumption is: 0.049×0.005×3=0.000735g.

[0078] In one possible embodiment, if the surface area A (unit: dm 2 ) and the process fill thickness Z (unit: μm), the silver consumption can be directly calculated: Silver consumption (g) = 0.02667*A*Z, where 0.02667 is the conversion factor of silver derived from the density ρ = 10.49g / cm3). If the total area of the pattern on the wafer is A = 50mm 2 =0.005dm 2 , filling thickness Z = 3μm, then the silver consumption is: 0.02667×0.005×3=0.000399g.

[0079] It should be noted that the process filling thickness mentioned above is the thickness of the coating on the surface of the wafer when the wafer undergoes the electroplating process.

[0080] S420: Calculating the amount of metal ions required for electroplating multiple wafers based on the amount of metal ions required for electroplating a single wafer.

[0081] S430: Obtaining a preset replenishment amount of metal ions according to the amount of metal ions consumed during electroplating of the plurality of wafers.

[0082] The metal ions in this application specifically refer to gold ions and silver ions. This application calibrates the amount of water evaporation and the amount of metal ions consumed during wafer electroplating through experiments, reducing dependence on expensive and complex-to-maintain online concentration monitoring equipment, thereby reducing hardware costs.

[0083] In a possible embodiment, the silver ions and gold ions can be added to the electroplating solution in the form of solid powdered gold salt and silver salt, or the silver ions and gold ions can be added to the electroplating solution by dissolving the gold salt and silver salt into a solution.

[0084] In one embodiment, if Figure 5 As shown, when the plating chamber is performing a wafer electroplating process, the second water replenishment amount and the metal ion replenishment preset amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the plating chamber, and further include:

[0085] S510: Calculate the first average evaporation amount Q of the plating solution in the liquid storage tank per unit time t1 and the second average evaporation amount Q of the plating solution in a single plating chamber per unit time t2 .

[0086] The first average evaporation amount Q in this embodiment t1 The calculation of the second average evaporation amount Q is the same as that of the above step S210. For details, please refer to the above step S210 and will not be described in detail here. t2 The calculation of is the same as that of the above step S310. For details, please refer to the above step S310 and will not be described in detail here.

[0087] S520: Based on the first average evaporation amount Q t1 , the second average evaporation Q t2 , the number of plating chambers n, the number of wafers m, the water flow rate Q of the cleaned wafers back into the plating chamber r And the amount of water Q required to dissolve the metal salt w , calculate the second water replenishment amount required for the plating solution per unit time; the specific calculation formula is: Q3=Q t1 +Q t2 *nQ r *mQ w , where Q t1 Q is the first average evaporation amount of the plating solution in the reservoir per unit time, t2 is the second average evaporation amount of the plating solution in a single plating chamber per unit time, n is the number of plating chambers involved in the electroplating process, m is the number of wafers involved in the electroplating process, Q r The water flow rate back to the plating chamber to clean the wafer surface, Q w The amount of water required to dissolve silver and gold salts.

[0088] S300: Dynamically adjusting the metal salt concentration of the electroplating solution based on the metal salt concentration loss to correct the metal salt concentration loss.

[0089] In one embodiment, the present application replenishes the plating solution with a water volume corresponding to the first water replenishment amount calculated when the plating chamber is not connected to the production line to correct the water volume loss caused by evaporation of the plating solution.

[0090] In one embodiment, the present application replenishes the plating solution with a first water replenishment amount calculated based on the plating chamber being connected to the production line but not performing the wafer electroplating process, so as to correct the water capacity loss caused by evaporation of the plating solution.

[0091] In one embodiment, the present application adds a second water replenishment amount and a preset replenishment amount of metal ions to the plating solution based on the second water replenishment amount and the preset replenishment amount of metal ions calculated when the plating chamber is performing a wafer electroplating process, so as to correct the evaporation of the plating solution and the loss of metal salt concentration due to the electroplating reaction.

[0092] The present application monitors the working status of the plating chamber in real time, calculates the concentration loss of the plating chamber according to the different working statuses of the monitored plating chamber, and the concentration loss is the amount of metal ion loss and / or water capacity consumption. The concentration loss is then used to dynamically adjust the metal salt concentration of the plating solution to correct the metal salt concentration loss, thereby avoiding the difficulty of a single water and metal salt replenishment model in responding to the changing needs of the plating solution concentration under different working statuses of the plating chamber, and avoiding unnecessary waste of metal salts and water resources, thereby improving the replenishment accuracy of the metal salt concentration of the plating solution.

[0093] The present application can dynamically adjust the amount of water replenishment according to multiple factors such as the evaporation rate of the plating solution, metal ion consumption, and the flow rate of water returning to the plating chamber from the cleaned wafer surface when performing the wafer electroplating process in the plating chamber, thereby improving the accuracy of the plating solution concentration adjustment and thereby improving the plating quality of the wafer.

[0094] The present application can dynamically adjust the amount of water replenishment when performing the wafer electroplating process in the electroplating chamber based on multiple factors such as the evaporation rate of the plating solution, the consumption of metal ions, the flow rate of water returning to the electroplating chamber after cleaning the wafer surface, etc., so that the concentration of the plating solution is always maintained within the process window, thereby improving the accuracy of the plating solution concentration adjustment, and thereby improving the electroplating quality of the wafer, avoiding the problem that the model of single water and metal salt replenishment is difficult to cope with the interference of multiple factors.

[0095] The protection scope of the control method for maintaining the dynamic stability of the electroplating solution concentration described in the embodiment of the present application is not limited to the execution order of the steps listed in this embodiment. All solutions implemented by adding, reducing, or replacing steps in the prior art based on the principles of the present application are included in the protection scope of the present application.

[0096] In the second aspect of the embodiment of the present application, Figure 6 As shown, the present application provides a control system for maintaining dynamic stability of electroplating solution concentration, which is used to implement the method in any of the above embodiments, including:

[0097] The monitoring unit 1 is used to monitor the working status of the electroplating chamber and the changes in the metal salt concentration of the electroplating solution in real time.

[0098] The calculation unit 2 is connected to the monitoring unit 1 and is used to calculate the metal salt concentration loss based on the working state of the electroplating chamber, wherein, when the electroplating chamber is not performing the wafer electroplating process, the first water replenishment amount is calculated based on the evaporation amount of the electroplating chamber and / or the liquid storage tank; when the electroplating chamber is performing the wafer electroplating process, the second water replenishment amount and the metal ion replenishment preset amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid storage tank and the electroplating chamber.

[0099] The correction unit 3 is connected to the calculation unit 2 and is used to dynamically adjust the metal salt concentration of the electroplating solution based on the metal salt concentration loss to correct the metal salt concentration loss.

[0100] The present application can design different water and metal salt replenishment strategies according to the different working conditions of the electroplating chamber, dynamically adjust the changes in metal salt concentration, improve the accuracy of water and metal salt replenishment, and avoid the difficulty of a single water and metal salt replenishment model in coping with the concentration change requirements of the plating solution under different working conditions of the electroplating chamber.

[0101] The implementation device of the control method for maintaining the dynamic stability of the plating solution concentration described in this application includes but is not limited to the structure of a control system for maintaining the dynamic stability of the plating solution concentration listed in this embodiment. All structural deformations and replacements of the existing technology made according to the principles of this application are included in the scope of protection of this application.

[0102] An embodiment of the present application further provides an electronic device, including a memory and a processor, wherein the memory stores a program for running on the processor, and when the program is executed by the processor, the electronic device implements the control method provided in any of the above embodiments.

[0103] One embodiment of the present application also provides a readable storage medium, which stores a program. When the program is executed, it implements the method of any one of the above embodiments. A person of ordinary skill in the art will understand that all or part of the steps in the method of implementing the above embodiment can be completed by instructing the processor through a program. The program can be stored in a computer-readable storage medium, which is a non-transitory medium, such as a random access memory, a read-only memory, a flash memory, a hard disk, a solid-state drive, a magnetic tape, a floppy disk, an optical disc, and any combination thereof. The above storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that includes one or more available media. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a digital video disc (DVD)), or a semiconductor medium (for example, a solid-state drive (SSD)).

[0104] An embodiment of the present application further provides a computer program product, which includes one or more computer instructions. When the computer instruction is loaded and executed on a computing device, the process or function according to the embodiment of the present application is generated in whole or in part. The computer instruction can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instruction can be transmitted from a website, computer or data center to another website, computer or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode.

[0105] When the computer program product is executed by a computer, the computer executes the method of the aforementioned method embodiment. The computer program product can be a software installation package. When the aforementioned method is needed, the computer program product can be downloaded and executed on the computer.

[0106] The present application can adopt corresponding water replenishment and metal salt replenishment strategies according to different equipment operating conditions and process conditions, thereby improving the accuracy of water replenishment and metal salt replenishment, having strong adaptability, and avoiding the difficulty of a single water and metal salt replenishment model in coping with the changing requirements of the plating solution concentration under different working conditions of the plating chamber.

[0107] The present application can dynamically adjust the amount of water replenishment when performing the wafer electroplating process in the electroplating chamber based on multiple factors such as the evaporation rate of the plating solution, the metal ion consumption, the flow rate of water returning to the electroplating chamber after cleaning the wafer surface, etc., so that the concentration of the plating solution is always maintained within the process window, thereby improving the accuracy of the plating solution concentration adjustment and thereby improving the electroplating quality of the wafer.

[0108] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices or methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of modules / units is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or units can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules or units, which can be electrical, mechanical or other forms.

[0109] The modules / units described as separate components may or may not be physically separate, and the components displayed as modules / units may or may not be physical modules, that is, they may be located in one place or distributed across multiple network elements. Some or all of the modules / units may be selected according to actual needs to achieve the purpose of the embodiments of the present application. For example, the functional modules / units in the various embodiments of the present application may be integrated into a processing module, or each module / unit may exist physically separately, or two or more modules / units may be integrated into a single module / unit.

[0110] Those skilled in the art should further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the composition and steps of each example according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0111] The descriptions of the processes or structures corresponding to the above figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0112] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. A control method for maintaining the dynamic stability of electroplating solution concentration, characterized in that: The control method is applied to an electroplating system, wherein the electroplating system includes an electroplating chamber and a liquid storage tank, and the control method includes: Real-time monitoring of the working status of the electroplating chamber; Calculating the metal salt concentration loss based on the working state of the electroplating chamber, wherein, when the electroplating chamber is not performing a wafer electroplating process, a first water replenishment amount is calculated based on the evaporation amount of the electroplating chamber and / or the liquid reservoir; and when the electroplating chamber is performing a wafer electroplating process, a second water replenishment amount and a preset metal ion replenishment amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the electroplating chamber; The metal salt concentration of the electroplating solution is dynamically adjusted based on the metal salt concentration loss to correct the metal salt concentration loss.

2. The control method according to claim 1, characterized in that: When the plating chamber is not performing a wafer electroplating process, calculating the first water replenishment amount based on the evaporation amount of the plating chamber and / or the liquid storage tank includes: Calculate the first average evaporation amount of the electroplating solution in the liquid storage tank per unit time; A first water replenishment amount of the electroplating solution is calculated according to a preset water replenishment interval and the first average evaporation amount.

3. The control method according to claim 1, wherein: When the plating chamber is not performing a wafer electroplating process, calculating the first water replenishment amount based on the evaporation amount of the plating chamber and / or the liquid storage tank further includes: Calculating a first average evaporation amount of the electroplating solution in the liquid storage tank per unit time and a second average evaporation amount of the electroplating solution in a single electroplating chamber per unit time; A first water replenishment amount required for the electroplating solution per unit time is calculated based on the first average evaporation amount, the second average evaporation amount, and the number of the electroplating chambers.

4. The control method according to claim 1, wherein: When the electroplating chamber performs a wafer electroplating process, the second water replenishment amount and the preset metal ion replenishment amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the electroplating chamber, including: Calculate the amount of metal ions required for electroplating a single wafer based on the wafer's surface area and process fill thickness; Calculate the amount of metal ions required for electroplating multiple wafers based on the amount of metal ions required for electroplating a single wafer. A preset replenishment amount of metal ions is obtained according to the amount of metal ions consumed during electroplating of the plurality of wafers.

5. The control method according to claim 4, characterized in that: When the electroplating chamber performs a wafer electroplating process, the second water replenishment amount and the preset metal ion replenishment amount are calculated based on the metal ion consumption of the wafer electroplating process, the evaporation amount of the liquid reservoir and the electroplating chamber, and further comprising: Calculating a first average evaporation amount of the plating solution in the liquid storage tank per unit time and a second average evaporation amount of the plating solution in a single plating chamber per unit time; The second water replenishment amount required for the plating solution per unit time is calculated based on the first average evaporation amount, the second average evaporation amount, the number of plating chambers, the number of wafers, the water flow rate of the cleaned wafers returning to the plating chamber, and the amount of water consumed by the dissolution of the metal salt.

6. The control method according to any one of claims 2 to 5, characterized in that: The calculating of a first average evaporation amount of the electroplating solution in the liquid storage tank per unit time includes: Calibrate and record the initial liquid level L0 of the electroplating solution in the reservoir or the initial weight W0 of the reservoir; The liquid level of the electroplating solution or the weight of the liquid storage tank is measured once every time interval Δt. The total time required after N measurements is Ttotal and the measured liquid level of the electroplating solution is L N The measured weight of the liquid storage tank is W N ; According to the initial weight W0 of the liquid storage tank and the weight W after N measurements N and the total time Ttotal, calculate the first average evaporation amount of the liquid storage tank in unit time or the initial liquid level L0 of the plating solution and the liquid level L after N measurements of the plating solution N The first average evaporation amount of the liquid storage tank per unit time is calculated based on the total time Ttotal.

7. A control system for maintaining dynamic stability of electroplating solution concentration, applied to the method according to any one of claims 1 to 6, characterized in that: include: A monitoring unit, used to monitor the working status of the electroplating chamber in real time; a calculation unit connected to the monitoring unit, and configured to calculate a metal salt concentration loss based on an operating state of the electroplating chamber, wherein, when the electroplating chamber is not performing a wafer electroplating process, a first water replenishment amount is calculated based on an evaporation amount of the electroplating chamber and / or the liquid reservoir; and when the electroplating chamber is performing a wafer electroplating process, a second water replenishment amount and a preset metal ion replenishment amount are calculated based on metal ion consumption in the wafer electroplating process, evaporation amount of the liquid reservoir and the electroplating chamber; A correction unit is connected to the calculation unit and is used to dynamically adjust the metal salt concentration of the electroplating solution based on the metal salt concentration loss to correct the metal salt concentration loss.

8. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a program for running on the processor, and when the program is executed by the processor, the electronic device implements the method according to any one of claims 1 to 6.

9. A readable storage medium having a program stored therein, characterized in that: When the program is executed, the method according to any one of claims 1 to 6 is implemented.

10. A computer program product, characterized in that The computer program product can be directly loaded into the data storage device of the computing unit of the control system for maintaining the dynamic stability of the plating liquid concentration according to claim 7, and the computer program product has a program code mechanism so that when the computer program product is executed in the control system for maintaining the dynamic stability of the plating liquid concentration, the method according to any one of claims 1 to 6 is executed.

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