Ceramic substrate through hole electro-coppering filling process control method

Abstract

The invention relates to the technical field of electroplating, and discloses a ceramic substrate through hole electro-coppering hole filling process control method which comprises the following steps: acquiring structural parameters of a target ceramic substrate through hole, optimizing the proportion of a prefabricated electroplating solution to obtain a proportioned electroplating solution, analyzing a composite electroplating medium of the proportioned electroplating solution, and inquiring a pulse current waveform; the copper deposition morphology is monitored, polarization effect coefficients under different current densities are calculated, duty ratio indexes are optimized to score a shaped current sequence, a multi-order electric field is applied to obtain in-hole flow field data, and the copper deposition uniformity is calculated; and performing multi-cycle electroplating-annealing iteration to obtain a copper hole filling structure, testing residual stress, identifying a lattice distortion section, generating a crystallization-annealing curve, and formulating a process optimization scheme according to regulation and control data. According to the invention, the reliability of the through hole electro-coppering filling process can be improved.

Description

Technical Field

[0001] The invention relates to a ceramic substrate through-hole electroplating copper filling process control method, belonging to the technical field of electroplating. Background Art

[0002] Ceramic substrates are widely used in power modules, LED packaging and other fields due to their excellent insulation, high temperature resistance and thermal conductivity. The core of their through-hole copper plating filling process is to achieve void-free and defect-free copper filling to ensure electrical connectivity and mechanical strength.

[0003] At present, the existing technology mainly adopts pulse electroplating or direct current electroplating combined with additives to fill holes, but there are the following shortcomings: First, the process parameters (such as current density, plating solution composition, temperature, etc.) are fixed, which is difficult to adapt to through-holes with different apertures and aspect ratios, and is prone to uneven plating or voids in the holes; second, there is a lack of real-time monitoring and feedback mechanism, and it is impossible to dynamically adjust the electroplating parameters to optimize the filling quality; third, the consumption of additives is unstable, which may cause fluctuations in the plating performance. These problems lead to low hole filling qualification rate, high production cost, and affect the consistency and reliability of the device. Therefore, it is necessary to develop a ceramic substrate through-hole electroplating copper filling process control, through multi-parameter collaborative optimization and real-time regulation, so as to improve the reliability of the through-hole electroplating copper filling process. Summary of the Invention

[0004] The present invention provides a method for controlling a through-hole copper plating filling process of a ceramic substrate, the main purpose of which is to improve the reliability of the through-hole copper plating filling process.

[0005] To achieve the above-mentioned object, the present invention provides a method for controlling a through-hole copper plating filling process of a ceramic substrate, comprising:

[0006] Obtaining through-hole structural parameters corresponding to a target ceramic substrate, optimizing the ratio of a prefabricated electroplating solution based on the through-hole structural parameters to obtain a proportioned electroplating solution, analyzing a composite electroplating medium corresponding to the proportioned electroplating solution, and querying a pulse current waveform corresponding to the composite electroplating medium;

[0007] monitoring the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process, extracting the pore opening accumulation thickness and pore bottom coverage corresponding to the copper deposition morphology, and calculating the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore opening accumulation thickness and pore bottom coverage;

[0008] Based on the polarization effect coefficient, optimizing the duty cycle index in the pulse current waveform, gradient-adjusting the duty cycle index to obtain a fractal current sequence, applying a multi-order electric field to the fractal current sequence to obtain in-hole flow field data, and calculating the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process based on the in-hole flow field data;

[0009] Based on the copper deposition uniformity, performing a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate to obtain a copper-filled hole structure, testing the residual stress in the hole of the copper-filled hole structure under high-temperature thermal cycling, and identifying a lattice distortion section in the residual stress in the hole;

[0010] According to the lattice distortion section, a crystallization-annealing curve corresponding to the copper hole-filling structure is generated, key inflection points in the crystallization-annealing curve are extracted, and control data corresponding to the key inflection points are analyzed. Based on the control data, a process optimization plan corresponding to the copper hole-filling structure is formulated.

[0011] Optionally, optimizing the ratio of the prefabricated electroplating solution based on the through-hole structure parameters to obtain the ratio electroplating solution includes:

[0012] Analyzing electroplating constraints corresponding to the through-hole structural parameters;

[0013] determining candidate plating solution compositions under the electroplating constraints;

[0014] Analyze the plating solution ratio and composition corresponding to the prefabricated electroplating solution;

[0015] Compatibly combining the plating solution ratio components with the optimized ratio components to obtain a plating solution ratio;

[0016] Based on the plating solution combination ratio, the prefabricated electroplating solution is optimized to obtain a proportioned electroplating solution.

[0017] Optionally, analyzing the composite electroplating medium corresponding to the proportioned electroplating solution includes:

[0018] collecting electrochemical signals of the proportioned electroplating solution during the electrodeposition process;

[0019] Extracting a deposition characteristic sequence corresponding to the electroplating solution based on the electrochemical signal;

[0020] Determining a deposition threshold interval corresponding to the electroplating solution according to the deposition characteristic sequence;

[0021] analyzing the ratio-deposition relationship in the deposition threshold interval;

[0022] Based on the ratio-deposition relationship, the composite electroplating medium corresponding to the ratio of the electroplating solution is analyzed.

[0023] Optionally, monitoring the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process includes:

[0024] Obtaining pulse plating parameters required for holes in the target ceramic substrate;

[0025] Based on the pulse electroplating parameters, collecting current distribution data in the holes in the target ceramic substrate;

[0026] Analyzing abnormal area characteristics corresponding to the current distribution data;

[0027] Based on the abnormal area characteristics, querying the critical process threshold corresponding to the holes in the target ceramic substrate;

[0028] The copper deposition morphology of the holes in the target ceramic substrate during the pulse electroplating process is monitored according to the critical process threshold.

[0029] Optionally, the calculating of the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore opening accumulation thickness and the pore bottom coverage includes:

[0030] The polarization effect coefficient of the composite electroplating medium at different current densities was calculated using the following formula:

[0031]

[0032] Wherein, Jα represents the polarization effect coefficient of the composite electroplating medium at different current densities, t represents the cumulative electroplating time, d represents the through-hole depth, n represents the total number of sampling points of current density, i represents the number index of sampling points, ΔE i represents the change in polarization potential at the i-th sampling point, C i represents the bottom coverage of the ith sampling point, H i represents the orifice accumulation thickness at the i-th sampling point, Δj i Indicates the change in current density at the i-th sampling point, H th represents the thickness threshold of the orifice accumulation thickness, λ represents the comprehensive coordination factor, β represents the correction coefficient corresponding to the current density, and j i Represents the current density value of the i-th sampling point.

[0033] Optionally, optimizing the duty cycle index in the pulse current waveform based on the polarization effect coefficient includes:

[0034] Based on the polarization effect coefficient, collecting historical duty cycle data corresponding to the pulse current waveform;

[0035] Analyzing polarization response characteristics corresponding to the historical duty cycle data;

[0036] Determining a duty cycle optimization direction corresponding to the pulse current waveform based on the polarization response characteristics;

[0037] Extracting a duty cycle adjustment point corresponding to the pulse current waveform according to the duty cycle optimization direction;

[0038] Based on the duty cycle adjustment point, a duty cycle index in the pulse current waveform is optimized.

[0039] Optionally, the calculating, based on the in-hole flow field data, the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process includes:

[0040] The copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process was calculated using the following formula:

[0041]

[0042] Wherein, Ud represents the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process, M represents the total number of sampling points of the flow field in the hole, j represents the number index of the sampling points, and h j The table shows the copper deposition thickness in the hole corresponding to the sampling point of the i-th data. represents the average deposition thickness of all sampling points, T represents the total filling time corresponding to the dynamic hole filling process, represents the dispersion of the plating solution at the i-th collection point,<V(t)> It represents the average velocity modulus of the flow field in the entire hole at time t.

[0043] Optionally, performing a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate according to the copper deposition uniformity to obtain a copper hole-filling structure includes:

[0044] analyzing hole filling data corresponding to the copper deposition uniformity;

[0045] determining a periodic configuration corresponding to the holes in the target ceramic substrate based on the hole filling data;

[0046] Query the configuration optimization index corresponding to the periodic configuration;

[0047] generating an execution sequence corresponding to the holes in the target ceramic substrate based on the configuration optimization index;

[0048] Based on the execution sequence, a multi-cycle electroplating-annealing iterative process is performed on the holes in the target ceramic substrate to obtain a copper hole-filling structure.

[0049] Optionally, identifying a lattice distortion section in the residual stress in the hole comprises:

[0050] Analyzing a stress distribution map corresponding to the residual stress in the hole;

[0051] Determining a critical distortion index corresponding to the lattice distortion based on the stress distribution map;

[0052] According to the critical distortion index, dividing the distortion risk gradient corresponding to the residual stress in the hole;

[0053] extracting local distortion core points in the distortion risk gradient;

[0054] Based on the local distortion core points, lattice distortion sections in the residual stress within the hole are identified.

[0055] Optionally, generating a crystallization-annealing curve corresponding to the copper hole-filling structure according to the lattice distortion section includes:

[0056] Marking the stress distribution of the section corresponding to the lattice distortion section;

[0057] Dividing the filling adaptation area corresponding to the stress distribution of the segment;

[0058] Querying the regional regulation index in the filling adaptation area;

[0059] Based on the regional regulation index, regulating the electrodeposition rate corresponding to the copper hole-filling structure;

[0060] A crystallization-annealing curve corresponding to the copper hole-filling structure is generated based on the electrodeposition rate.

[0061] Compared with the problems described in the background technology, the present invention can accurately adapt to the characteristics of through-holes of different specifications by obtaining the through-hole structural parameters corresponding to the target ceramic substrate, and can perform targeted ratio optimization on the prefabricated electroplating solution, and can also provide an important basis for the subsequent selection of pulse current waveforms, monitoring and regulation of the electroplating process, thereby effectively avoiding problems such as uneven coating and voids in the holes. The present invention can obtain key data such as hole mouth accumulation thickness and hole bottom coverage in real time by monitoring the copper deposition morphology of the holes in the target ceramic substrate during the pulse electroplating process, providing an intuitive basis for accurately regulating electroplating parameters and optimizing the deposition process, and effectively improving the controllability and consistency of hole filling quality. Furthermore, based on the polarization effect coefficient, the present invention optimizes the duty cycle index in the pulse current waveform, can accurately adapt to the characteristics of the composite electroplating medium, dynamically balance the difference in deposition between the hole mouth and the hole bottom, and suppress polarization anomalies. It helps to build a more stable and efficient pulse electroplating process and improve the quality and reliability of ceramic substrate hole filling. Furthermore, the present invention performs multi-cycle electroplating-annealing iterative processing on the holes in the target ceramic substrate according to the copper deposition uniformity to obtain a copper hole filling structure. It can accurately control the electroplating parameters of each round based on the uniformity feedback, optimize the copper deposition distribution, and finally construct a dense and uniform copper hole filling structure to ensure the electrical performance and reliability of the ceramic substrate and adapt to high-demand application scenarios. Finally, the present invention generates a crystallization-annealing curve corresponding to the copper hole filling structure according to the lattice distortion section. It can accurately design the annealing temperature-time parameters for the microscopic defects (such as dislocations and grain boundary stresses) in the distortion area, and repair the lattice damage in a direction. It can provide differentiated annealing schemes for multi-cycle electroplating-annealing processes, improve the microstructural consistency and thermal stability of the hole filling structure, and enhance fatigue resistance. Therefore, the ceramic substrate through-hole electroplating copper filling process control method provided in the embodiment of the present invention can improve the reliability of the through-hole electroplating copper filling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A schematic flow chart of a method for controlling a through-hole copper plating filling process of a ceramic substrate provided by one embodiment of the present invention;

[0063] Figure 2 A schematic flow chart of a plating solution filling process in a method for controlling a through-hole copper plating filling process of a ceramic substrate provided by one embodiment of the present invention;

[0064] Figure 3 A schematic diagram of a module for implementing a ceramic substrate through-hole copper plating filling process control system provided in one embodiment of the present invention.

[0065] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0066] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0067] The present embodiment provides a method for controlling a through-hole copper plating process for ceramic substrates. The method can be executed by at least one of electronic devices, such as a server or a terminal, that can be configured to execute the method provided by the present embodiment. In other words, the method can be executed by software or hardware installed on a terminal or server. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster.

[0068] Example 1:

[0069] Reference Figure 1 FIG. 1 is a flow chart of a method for controlling a through-hole copper plating filling process of a ceramic substrate according to an embodiment of the present invention. In this embodiment, the method for controlling a through-hole copper plating filling process of a ceramic substrate includes:

[0070] S1. Obtain through-hole structural parameters corresponding to a target ceramic substrate, optimize the ratio of a prefabricated electroplating solution based on the through-hole structural parameters to obtain a proportioned electroplating solution, analyze a composite electroplating medium corresponding to the proportioned electroplating solution, and query a pulse current waveform corresponding to the composite electroplating medium.

[0071] By obtaining the through-hole structural parameters corresponding to the target ceramic substrate, the present invention can accurately adapt to the characteristics of through-holes of different specifications, and can perform targeted ratio optimization of the prefabricated electroplating solution. It can also provide an important basis for subsequent pulse current waveform selection, electroplating process monitoring and regulation, thereby effectively avoiding problems such as uneven coating and voids in the holes.

[0072] Among them, the target ceramic substrate refers to the ceramic substrate to be processed in the ceramic substrate through-hole electroplating copper filling process. As the object of the process implementation, it has specific properties such as material, size and through-hole distribution. For example, the aluminum nitride ceramic substrate used in the 5G power module has a number of through-holes for electrical connection distributed on its surface, and high-quality copper filling is required through this process; the through-hole structure parameters refer to the parameters that characterize the geometric characteristics of the through-holes on the target ceramic substrate, mainly including aperture size (through-hole diameter), aspect ratio (ratio of hole depth to aperture), hole density (number of through-holes per unit area), etc. For example, if the through-hole diameter on the ceramic substrate is 100μm, the aspect ratio is 5:1, and the hole density is 200 / cm 2These parameters directly affect the selection of the electroplating solution ratio and the pulse current waveform. Optionally, the acquisition of the through-hole structural parameters corresponding to the target ceramic substrate can be achieved through three-dimensional scanning imaging technology, such as: using industrial CT scanning combined with VGStudio software to reconstruct the through-hole three-dimensional model, and finally obtaining the through-hole structural parameters including the aperture depth and position accuracy.

[0073] Furthermore, the present invention optimizes the ratio of the prefabricated electroplating solution based on the through-hole structure parameters to obtain a proportioned electroplating solution. The concentration ratio of copper sulfate, sulfuric acid and additives (such as accelerators, levelers, and inhibitors) in the plating solution can be accurately controlled according to different pore diameters, aspect ratios, and other characteristics. This can significantly enhance the matching degree between the plating solution and the through-hole, and reduce problems such as uneven plating and voids in the hole.

[0074] The prefabricated electroplating solution refers to a basic electroplating solution containing conductive substances such as copper ions and various additives that is prepared in advance before the copper plating filling process of the through-holes of the ceramic substrate begins. It usually contains basic components such as copper sulfate, sulfuric acid, chloride ions, and functional additives such as accelerators, levelers, and inhibitors. For example, a mixed solution composed of 80-120g / L copper sulfate, 150-200g / L sulfuric acid, 50-80ppm chloride ions, and a certain concentration of sodium polydisulfide, ethylene thiourea, polyethyleneimine, etc. can be used as a subsequent mixing ratio. The optimized base liquid; the proportioned electroplating solution refers to an electroplating solution adapted to a specific through-hole structure obtained by analyzing the electroplating constraints corresponding to the through-hole structure parameters, screening candidate plating solution components, and combining them with the proportioned components of the prefabricated electroplating solution. For example, for a through-hole with a pore size of 150 μm and an aspect ratio of 7:1, the optimized plating solution containing 110 g / L copper sulfate, 190 g / L sulfuric acid, 70 ppm chloride ions, 8 mg / L accelerator, 3 mg / L leveler, and 22 mg / L inhibitor is the proportioned electroplating solution for this scenario.

[0075] As an embodiment of the present invention, the ratio optimization of the prefabricated electroplating solution based on the through-hole structure parameters to obtain the ratio electroplating solution includes: analyzing the electroplating constraints corresponding to the through-hole structure parameters; determining the candidate components of the plating solution under the electroplating constraints; analyzing the plating solution ratio components corresponding to the prefabricated electroplating solution; compatibly combining the plating solution ratio components with the optimized ratio components to obtain the plating solution combination ratio; and optimizing the ratio of the prefabricated electroplating solution based on the plating solution combination ratio to obtain the ratio electroplating solution.

[0076] Among them, the electroplating constraints refer to the electroplating process constraints determined by the through-hole structural parameters (such as pore size, aspect ratio, and hole density), including plating solution fluidity, copper ion diffusion efficiency, deposition rate matching, etc. For example, for a through-hole with an aspect ratio of 8:1, due to its deep and narrow channels, the plating solution is required to have high dispersion ability and a faster deposition rate in the hole, otherwise voids at the bottom of the hole are likely to appear, which constitutes a constraint on the composition and concentration of the plating solution; the candidate plating solution components refer to functional chemical substances that can be used to adjust the performance of the plating solution under the electroplating constraints, mainly including additives such as accelerators, levelers, and inhibitors. For example, for through-holes with an aspect ratio greater than 5:1, candidate components may include sodium polydisulfide dipropylene sulfonate (accelerator) and ethylene thiourea (leveler) to improve the copper deposition rate and surface flatness in the hole; the plating solution ratio The composition refers to the initial concentration ratio of each basic component (such as copper sulfate, sulfuric acid, and chloride ions) and additives in the prefabricated electroplating solution. For example, the composition of the prefabricated electroplating solution can be: 100g / L copper sulfate, 180g / L sulfuric acid, 60ppm chloride ions, 5mg / L accelerator, 2mg / L leveler, and 30mg / L suppressor. These component ratios determine the basic performance of the plating solution. The plating solution combination ratio refers to the final concentration ratio of each component after the composition ratio of the candidate plating solution components and the prefabricated electroplating solution is adjusted for compatibility based on the electroplating constraints. For example, when the through-hole aspect ratio is 6:1, the accelerator is increased from 5mg / L to 8mg / L, the leveler is increased from 2mg / L to 3mg / L, and the suppressor is reduced from 30mg / L to 25mg / L to form a new combination ratio to optimize the hole filling effect.

[0077] Furthermore, the analysis of the electroplating constraints corresponding to the through-hole structural parameters can be achieved through electrochemical simulation modeling, such as: using the current distribution module of COMSOL Multiphysics to calculate the relationship between the through-hole aspect ratio and the current density, and finally obtaining the electroplating constraints including the minimum plating thickness; the determination of the candidate components of the plating solution under the electroplating constraints can be achieved through material database matching, such as: screening the additive combination that meets the conductivity requirements based on the plating solution performance index of the MatNavi database, and finally obtaining the candidate components of the plating solution that meet the process indicators; the analysis of the plating solution ratio components corresponding to the prefabricated electroplating solution can be achieved through spectral detection technology, such as: using an ICP-OES spectrometer in combination with ChemStation software to quantitatively analyze metal ions concentration, ultimately obtaining a plating solution ratio accurate to the ppm level; the compatible combination of the plating solution ratio components and the optimized ratio components can be achieved through a multi-objective optimization algorithm, such as: using the NSGA-II genetic algorithm to solve the component Pareto frontier solution in Python's DEAP library, and ultimately obtaining a plating solution combination ratio that takes into account both deposition rate and uniformity; the ratio optimization of the prefabricated electroplating solution can be achieved through response surface analysis, such as: using Design-Expert software to establish a second-order regression model of plating solution composition and coating quality, and ultimately obtaining a ratioed electroplating solution that meets both electrical conductivity and adhesion strength standards.

[0078] By analyzing the composite electroplating medium corresponding to the ratio of the electroplating solution, the present invention can accurately grasp the influence of key parameters such as the electroplating solution conductivity, pH value, and temperature on the electroplating process, and can provide data support for the selection of pulse current waveforms and the calculation of polarization effects, ensuring that the plating solution performance matches the depth of the through-hole structure, thereby improving the uniformity of copper deposition and the quality of hole filling.

[0079] Among them, the composite electroplating medium refers to a complex electrochemical system composed of the basic components (copper salt, acid, supporting electrolyte) in the proportioned electroplating solution, additives and solvent (water). Its physicochemical properties (such as conductivity, pH value, interfacial tension) and electrochemical behavior (such as polarization characteristics, diffusion coefficient) directly affect the copper deposition process. For example, an aqueous solution containing 100g / L copper sulfate, 180g / L sulfuric acid, 60ppm chloride ions and optimized concentration additives, as a composite electroplating medium, determines the quality and efficiency of copper filling in the through-hole.

[0080] As an embodiment of the present invention, the analysis of the composite electroplating medium corresponding to the proportioned electroplating solution includes: collecting the electrochemical signal of the proportioned electroplating solution during the electrodeposition process; extracting the deposition characteristic sequence corresponding to the proportioned electroplating solution based on the electrochemical signal; determining the deposition threshold interval corresponding to the proportioned electroplating solution according to the deposition characteristic sequence; analyzing the proportion-deposition relationship in the deposition threshold interval; and analyzing the composite electroplating medium corresponding to the proportioned electroplating solution based on the proportion-deposition relationship.

[0081] Among them, the electrochemical signal refers to the signal related to the electrochemical reaction generated by the ratio electroplating solution during the electroplating process, such as real-time data such as polarization potential, current density, and impedance. For example, the potential fluctuation curve over time during the pulse electroplating process collected by the electrochemical workstation can reflect the kinetic characteristics of copper ion reduction deposition in the plating solution; the deposition characteristic sequence refers to the characteristic parameter sequence that can characterize the copper deposition behavior extracted from the electrochemical signal, including deposition rate, polarization degree, grain growth rate, etc. For example, by analyzing the potential-time curve, the deposition rate sequence of a certain ratio electroplating solution at different current densities (such as 0.5μm / min, 0.8μm / min, 1.2μm / min) is obtained, reflecting the change in the deposition activity of the plating solution; the deposition threshold interval refers to the interval that ensures copper in the through hole. The key parameter ranges for uniform, defect-free deposition include current density threshold, potential threshold, additive concentration threshold, etc. For example, when the accelerator concentration in the plating solution is lower than 5 mg / L, the deposition rate at the bottom of the hole is lower than 0.3 μm / min, and voids are easily formed. Therefore, the lower limit threshold of the accelerator concentration is determined to be 5 mg / L, which constitutes part of the deposition threshold range; the ratio-deposition relationship refers to the corresponding relationship between the concentration of each component in the plating solution (such as copper sulfate, accelerator, inhibitor) and the copper deposition characteristics (such as rate, uniformity, porosity). For example, experiments have found that when the sulfuric acid concentration increases from 150 g / L to 200 g / L, the conductivity of the plating solution increases by 3 mS / cm and the deposition rate increases by 20%. However, too high a concentration will lead to coarse grains, forming a ternary relationship of "concentration-rate-grain size".

[0082] Furthermore, the electrochemical signal of the electroplating solution during the electroplating process can be collected by dynamic monitoring using a potentiostat, such as a Gamry Interface The 5000 electrochemical workstation records polarization curves and impedance spectra, ultimately obtaining electrochemical signals including potential and current changes. The extraction of the deposition characteristic sequence corresponding to the ratioed electroplating solution can be achieved through time-frequency joint analysis, such as using Python's SciPy library to perform wavelet transform decomposition on the current oscillation signal, ultimately obtaining a deposition characteristic sequence reflecting the nucleation and growth stage. The determination of the deposition threshold interval corresponding to the ratioed electroplating solution can be achieved through statistical process control, such as analyzing the coating thickness fluctuation boundary based on the Six Sigma control chart of Minitab software, ultimately obtaining a deposition threshold interval that meets the 3σ principle. The analysis of the ratio-deposition relationship in the deposition threshold interval can be achieved through symbolic regression modeling, such as using the Eureqa platform to automatically generate a nonlinear equation of the plating solution composition and the deposition rate, ultimately obtaining a ratio-deposition relationship with a quantified influence weight. The analysis of the composite electroplating medium corresponding to the ratioed electroplating solution can be achieved through nano-characterization technology, such as using a FE-SEM energy spectrum coupling system combined with an ImageJ particle analysis plug-in, ultimately obtaining a composite electroplating medium with a uniform dispersed phase distribution.

[0083] By querying the pulse current waveform corresponding to the composite electroplating medium, the present invention can effectively enhance the transmission efficiency of copper ions in the plating solution according to the physical and chemical properties of the plating solution, optimize the polarization effect, and help achieve more uniform and dense copper deposition, avoiding voids in the holes and uneven plating, and greatly improving the quality of copper plating filling in through-holes of ceramic substrates.

[0084] The pulse current waveform refers to the waveform in which the current density changes periodically with time during the electroplating process. It is usually composed of parameters such as pulse width (on time), pulse interval (off time), frequency, and peak current density. It affects the quality of the coating by regulating the deposition and diffusion process of copper ions. For example, if the pulse current waveform parameters are: frequency 100Hz, duty cycle 50%, peak current density 3A / dm 2 , which is conducted for 5ms every 10ms (current 3A / dm 2 ), turn off 5ms (current 0A / dm 2 ), which can be used to improve the uniformity of copper deposition in micropores. Optionally, the query of the pulse current waveform corresponding to the composite electroplating medium can be achieved by searching the electrodeposition process database, such as using the API interface of the Materials Project platform to match the plating solution components with typical pulse parameters, and finally obtaining a pulse current waveform including the duty cycle frequency.

[0085] S2. Monitor the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process, extract the pore opening accumulation thickness and pore bottom coverage corresponding to the copper deposition morphology, and calculate the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore opening accumulation thickness and pore bottom coverage.

[0086] By monitoring the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process, the present invention can obtain key data such as the pore mouth accumulation thickness and the pore bottom coverage in real time, providing an intuitive basis for accurately controlling the electroplating parameters and optimizing the deposition process, and effectively improving the controllability and consistency of the hole filling quality.

[0087] The pulse plating process refers to the use of periodic intermittent current to replace the traditional DC plating method. By controlling the pulse frequency, duty cycle, peak current density and other parameters, the deposition and diffusion behavior of copper ions in the through-hole are adjusted. For example, in the through-hole electroplating of ceramic substrates, the pulse frequency is set to 500Hz, the duty cycle is 30%, and the peak current density is 5A / dm 2 , that is, it is turned on for 0.6ms (high current promotes deposition) and turned off for 1.4ms (low current promotes ion diffusion) within every 2ms, which can reduce concentration polarization and improve the uniformity and density of copper deposition in the hole; the copper deposition morphology refers to the microscopic and macroscopic morphology formed by copper deposition in the hole, including the thickness distribution of the deposited layer, surface flatness, grain size and orientation, etc. For example, the ideal morphology should be uniform coverage in the hole, without voids and cracks, while abnormal morphology may manifest as nodules at the hole mouth (accumulation thickness > plating 15%) or a thin copper layer at the bottom of the hole (coverage <95%).

[0088] As an embodiment of the present invention, the monitoring of the copper deposition morphology of the holes in the target ceramic substrate during the pulse electroplating process includes: obtaining pulse electroplating parameters required for the holes in the target ceramic substrate; based on the pulse electroplating parameters, collecting current distribution data in the holes in the target ceramic substrate; analyzing abnormal area characteristics corresponding to the current distribution data; based on the abnormal area characteristics, querying the critical process threshold corresponding to the holes in the target ceramic substrate; and monitoring the copper deposition morphology of the holes in the target ceramic substrate during the pulse electroplating process according to the critical process threshold.

[0089] The pulse plating parameters refer to the electrical parameters that can be adjusted during the pulse plating process, including pulse frequency (such as 500Hz), duty cycle (such as 30%), peak current density (such as 5A / dm 2), average current density, etc. For example, for a through hole with an aspect ratio of 8:1, high-frequency and low-duty cycle parameters need to be set to enhance copper deposition at the bottom of the hole. These parameters directly affect the deposition rate and distribution of copper ions. The current distribution data refers to the quantitative data obtained by electrochemical probe or simulation calculation, reflecting the current density distribution at different positions in the hole during pulse electroplating. For example, the hole mouth current density at a certain moment measured by the microelectrode array is 3A / dm 2 , hole bottom is 1A / dm 2 This uneven distribution may lead to deposition differences and is a key indicator for monitoring. The abnormal area characteristics refer to the regional characteristics of the current distribution data that deviate from the normal deposition pattern, such as the current density is too high (> 5A / dm 2 ) caused by rapid deposition at the orifice, too low (<0.5A / dm 2 ) caused by the risk of hole bottom voids, for example, when the current density ratio between the hole mouth and the hole bottom is greater than 3:1, a "bottleneck" structure is easily formed, and parameters need to be adjusted in time; the critical process threshold refers to the critical value of the parameter to ensure the quality of copper deposition, including the current density threshold (such as the hole bottom current density ≥1A / dm 2 ), deposition rate threshold (such as 0.5-1.2μm / min), etc. For example, when the deposition rate at the bottom of the hole is monitored to be less than 0.3μm / min, the early warning mechanism is triggered, and the accelerator concentration needs to be increased or the pulse duty cycle needs to be adjusted.

[0090] Furthermore, the pulse plating parameters required for obtaining the holes in the target ceramic substrate can be achieved through multi-physics field coupling simulation, such as: using ANSYS Fluent combined with the electrochemical module to simulate the flow field distribution in the hole under different pulse width periods, and finally obtaining the pulse plating parameters that optimize the mass transfer efficiency; the current distribution data in the holes in the target ceramic substrate can be collected through microprobe array detection, such as: using a Keithley 4200 semiconductor parameter analyzer with a nanoscale tungsten probe to scan the hole wall current, and finally obtaining the current distribution data with submicron resolution; the analysis of the abnormal area features corresponding to the current distribution data can be achieved through an anomaly detection algorithm, such as: identifying current density outliers in Python's scikit-learn library based on the Isolation Forest algorithm, and finally obtaining the abnormal area features that mark the defect location; the query of the critical process threshold corresponding to the holes in the target ceramic substrate can be achieved through failure mode database matching, such as: through CES The critical current density for ceramic-copper interface peeling is retrieved from the EduPack material database, ultimately obtaining the critical process threshold for avoiding coating peeling; monitoring the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process can be achieved through in-situ microscopic imaging, such as using a Keyence VHX-7000 digital microscope with a high-speed camera module to capture the deposition front dynamics, ultimately obtaining a time series of copper deposition morphology.

[0091] By extracting the pore opening accumulation thickness and pore bottom coverage corresponding to the copper deposition morphology, the present invention can accurately determine whether the pore opening is closed prematurely and whether there is a risk of voids at the pore bottom, providing direct data support for calculating the polarization effect coefficient and optimizing the pulse current parameters, and then dynamically adjusting the process to improve the pore filling quality and ensure the electrical connectivity and mechanical strength of the through-holes of the ceramic substrate.

[0092] Among them, the hole mouth accumulation thickness refers to the abnormal thickening of the copper plating at the opening of the through hole of the ceramic substrate during the pulse electroplating process. It is usually due to the excessively high current density at the hole mouth, which leads to too fast copper deposition rate, forming an accumulation layer higher than other areas of the hole wall. For example, if the average plating thickness of the through hole wall is 10μm, and the plating thickness at the hole mouth edge is 13μm, the 3μm that exceeds the average thickness is the hole mouth accumulation thickness. Excessive accumulation may cause the effective aperture of the through hole to shrink or even close; the hole bottom coverage refers to the area ratio of the through hole bottom area covered by the copper plating layer, which reflects the integrity of the copper deposition at the bottom of the hole and is a key indicator for measuring the quality of hole filling. For example, for a through hole with a hole diameter of 100μm and a hole depth of 500μm, if the total area of ​​the hole bottom is 7854μm 2 , where the area uniformly covered by the copper plating is 7461μm 2, the hole bottom coverage is 95%. Below this value, there may be voids or incomplete filling problems. Optionally, the extraction of the hole mouth stacking thickness corresponding to the copper deposition morphology can be achieved by laser confocal microscopy measurement, such as: using a Keyence VK-X1000 series three-dimensional surface profiler to scan the hole mouth area, and finally obtaining the hole mouth stacking thickness with nanometer resolution; the extraction of the hole bottom coverage corresponding to the copper deposition morphology can be achieved by focused ion beam imaging, such as: using a Thermo Scientific Helios G4 UX dual-beam electron microscope to prepare the channel cross-section and calculate the coating coverage area ratio, and finally obtain the hole bottom coverage accurate to 1%.

[0093] Furthermore, the present invention calculates the polarization effect coefficient of the composite electroplating medium at different current densities based on the hole mouth accumulation thickness and hole bottom coverage, which can quantitatively reflect the polarization degree of the composite electroplating medium at different current densities and the difference in copper deposition behavior, help to accurately control the electroplating process, improve the uniformity of copper deposition, reduce the risk of defects in the hole, and ensure the stability and reliability of the hole filling process.

[0094] Among them, the polarization effect coefficient refers to a quantitative indicator that comprehensively reflects the strength of the polarization phenomenon and the degree of influence on the uniformity of copper deposition under the interaction of the hole mouth accumulation thickness, hole bottom coverage and current density of the composite electroplating medium during the pulse electroplating process. It integrates the hole mouth / hole bottom morphology parameters, current changes, etc. The numerical value reflects the significance of the polarization effect of the electroplating system, which is used to judge whether the process parameters are reasonable, guide the optimization of the electroplating process, and ensure the quality of hole filling.

[0095] As an embodiment of the present invention, the calculation of the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore stacking thickness and the pore bottom coverage includes:

[0096] The polarization effect coefficient of the composite electroplating medium at different current densities was calculated using the following formula:

[0097]

[0098] Wherein, Jα represents the polarization effect coefficient of the composite electroplating medium at different current densities, t represents the cumulative electroplating time, d represents the through-hole depth, n represents the total number of sampling points of current density, i represents the number index of sampling points, ΔE i represents the change in polarization potential at the i-th sampling point, C i represents the bottom coverage of the ith sampling point, H i represents the orifice accumulation thickness at the i-th sampling point, Δj i Indicates the change in current density at the i-th sampling point, H threpresents the thickness threshold of the orifice accumulation thickness, λ represents the comprehensive coordination factor, β represents the correction coefficient corresponding to the current density, and j i Represents the current density value of the i-th sampling point.

[0099] In detail, the cumulative electroplating time refers to the total time that the current continuously acts on the through-hole of the ceramic substrate from the start of pulse electroplating to the calculation of the polarization effect coefficient. It covers the sum of the time of all power-on stages in the electroplating process. It is a basic parameter reflecting the electroplating process and the total amount of ion deposition, affecting the thickness and uniformity of the copper layer growth in the hole, and is directly related to the deposition rate and the quality of the coating; the sampling points refer to a number of characteristic points (indexed by i) selected according to a certain rule within the current density adjustment range of pulse electroplating. These points correspond to different current density working conditions and are used to collect data such as the hole mouth accumulation thickness, hole bottom coverage, and polarization potential; the polarization potential change refers to the difference in the electrode potential from the equilibrium potential at the i-th sampling point during the electroplating process. Due to changes in current density, ion concentration polarization, etc., the actual potential is offset from the theoretical equilibrium potential. This value reflects the degree to which the electrochemical reaction is affected by polarization; the current density change refers to the difference between the "current current density-initial reference current density" corresponding to the i-th sampling point, which reflects the dynamic adjustment amplitude of the current density in pulse electroplating. Different Δj i It will change the ion migration rate and deposition behavior, and is the key variable in the formula that relates the current parameters to the pore morphology and polarization effect, reflecting the influence of the process parameters on the deposition results. The thickness threshold refers to the pre-set critical value for determining whether the pore stacking thickness is "abnormal". Based on the design requirements of the ceramic substrate through-hole (such as effective pore size and connectivity), it is determined through experiments or simulations. The formula used to quantify the pore stacking thickness (H i ) relative deviation Assess the risk of excessive accumulation at the orifice and assist in regulating the uniformity of deposition; the comprehensive coordination factor refers to the empirical correction coefficient introduced to adapt to the complexity of the actual electroplating system (such as fluctuations in the composition of the plating solution, differences in the substrate material, etc.). It is used to coordinate the deviation between the theoretical calculation and the actual process in the formula, and is determined through experimental calibration (such as comparing the polarization effect coefficient of the standard sample) to ensure the applicability of the formula in different production scenarios and optimize the matching degree between the calculation results and the actual process; the correction coefficient refers to the current density (j i ) has a nonlinear effect on the polarization effect and deposition behavior, and the adjustment coefficient is set. Because the change of current density not only changes the deposition rate, but also causes the complex coupling of concentration polarization and electrochemical polarization; the current density value refers to the current intensity per unit area of ​​the electrode surface at the i-th sampling point (such as A / dm 2), which is the core control parameter of pulse electroplating, directly determines the rate and distribution of ion migration and copper deposition. As the basic variable in the formula, it correlates the quantitative relationship between current input and in-hole deposition morphology and polarization effect, reflecting the electroplating behavior under different current conditions.

[0100] S3. Based on the polarization effect coefficient, optimize the duty cycle index in the pulse current waveform, perform gradient adjustment on the duty cycle index to obtain a fractal current sequence, apply a multi-order electric field to the fractal current sequence to obtain in-hole flow field data, and calculate the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process based on the in-hole flow field data.

[0101] Based on the polarization effect coefficient, the present invention optimizes the duty cycle index in the pulse current waveform, can accurately adapt to the characteristics of the composite electroplating medium, dynamically balance the deposition differences between the hole mouth and the hole bottom, suppress polarization anomalies, help build a more stable and efficient pulse electroplating process, and improve the quality and reliability of ceramic substrate hole filling.

[0102] Among them, the duty cycle index refers to the core parameter that describes the duty cycle of the pulse current waveform, which is expressed by the ratio of "on time / (on time + off time)", reflecting the proportion of current conduction in a pulse cycle and determining the time allocation for ion deposition and diffusion. For example, the pulse cycle is 2ms, the on time is 0.6ms, and the off time is 1.4ms. The duty cycle index is 30%. Its value directly affects the rate and uniformity of copper deposition in the hole and is a key variable for regulating the polarization effect.

[0103] As an embodiment of the present invention, optimizing the duty cycle index in the pulse current waveform based on the polarization effect coefficient includes: collecting historical duty cycle data corresponding to the pulse current waveform based on the polarization effect coefficient; analyzing polarization response characteristics corresponding to the historical duty cycle data; determining the duty cycle optimization direction corresponding to the pulse current waveform based on the polarization response characteristics; extracting the duty cycle adjustment point corresponding to the pulse current waveform according to the duty cycle optimization direction; and optimizing the duty cycle index in the pulse current waveform based on the duty cycle adjustment point.

[0104] The historical duty cycle data refers to the recorded data of the ratio of the pulse current on-time to the total cycle duration (duty cycle) in different process cycles in the past during the pulse electroplating process, covering the duty cycle settings and corresponding process parameters of different current densities and electroplating stages. For example, during electroplating of a certain batch, at a current density of 3A / dm 2In the first stage, the duty cycle is 30%, 32% and 28% respectively. The duty cycle values ​​of these related process conditions are the historical duty cycle data, which are used to trace and analyze the relationship between the duty cycle and the polarization effect; the polarization response characteristics refer to the regular performance of the positive polarization phenomenon of copper deposition in the hole corresponding to the historical duty cycle data, including the trend of the polarization effect coefficient changing with the duty cycle (such as whether the polarization effect coefficient increases or decreases when the duty cycle increases), and the fluctuation pattern of the hole mouth / hole bottom deposition difference. For example, the analysis found that when the duty cycle increases from 25% to 40%, the polarization effect coefficient first decreases and then increases, and the fluctuation amplitude of the hole bottom coverage changes synchronously. This "duty cycle-polarization" correlation law is the polarization response characteristic; the duty cycle optimization direction refers to a clear duty cycle adjustment strategy based on the polarization response characteristics. , which is used to guide the optimization of the duty cycle index, including increasing / decreasing the duty cycle, segmented adjustment trend, etc. For example, if the polarization response characteristics show that "the duty cycle is too high, resulting in aggravated pore accumulation (abnormal polarization effect coefficient)", the optimization direction is "reducing the duty cycle in the high current density stage" or "targetedly increasing the duty cycle in the weak deposition area at the bottom of the pore"; the duty cycle adjustment point refers to the specific moment or process node in the pulse current waveform where the duty cycle needs to be adjusted, corresponding to the key stage in the electroplating process where the polarization effect coefficient is abnormal and the deposition uniformity deteriorates. For example, at the 10th minute of electroplating (initial accumulation at the pore mouth) and the 20th minute (critical value of pore bottom coverage), the polarization effect coefficient exceeds the reasonable range. These time nodes or process stages are the duty cycle adjustment points, and the duty cycle needs to be corrected here.

[0105] Furthermore, the acquisition of historical duty cycle data corresponding to the pulse current waveform can be achieved through an electroplating process data acquisition system, such as: using a National Instruments PXIe-5160 high-speed digitizer to record pulse waveform timing parameters, and ultimately obtaining historical duty cycle data containing a time series; the analysis of polarization response characteristics corresponding to the historical duty cycle data can be achieved through electrochemical impedance spectroscopy analysis, such as: using a Gamry Reference 600+ impedance analyzer combined with ZView software to fit the Nyquist spectrum, and ultimately obtaining polarization response characteristics that characterize polarization behavior; the determination of the duty cycle optimization direction corresponding to the pulse current waveform can be achieved through response surface analysis, such as: establishing a second-order polynomial model of duty cycle and coating quality through Design-Expert software, and ultimately obtaining the duty cycle optimization direction for improving coating uniformity; the extraction of the duty cycle adjustment point corresponding to the pulse current waveform can be achieved through a variational mode decomposition algorithm, such as: decomposing the current waveform mutation characteristics based on the VMD toolbox of MATLAB, and ultimately obtaining the duty cycle adjustment point of the key process turning point; the optimization of the duty cycle index in the pulse current waveform can be achieved through a reinforcement learning algorithm, such as: using Deep Q-Network trains the duty cycle adjustment strategy under the TensorFlow framework and ultimately obtains the duty cycle index that maximizes the deposition rate.

[0106] The present invention obtains a fractal current sequence by gradient adjustment of the duty cycle index, which can accurately adapt to the needs of different stages of electroplating and dynamically control the ion deposition rhythm; optimizes the current distribution with the help of fractal characteristics, promotes the uniform growth of the copper layer in the hole, and alleviates polarization differences; and improves the stability of hole filling quality through differentiated current patterns.

[0107] Among them, the fractal current sequence refers to a pulse current sequence with self-similar and multi-scale characteristics generated by gradient adjustment of the duty cycle index. The current on and off time varies according to the fractal law and can adapt to the requirements of different stages of electroplating. For example, based on the initial duty cycle, it is adjusted in sequence according to a 1.5-fold gradient to form a current sequence with a dynamically evolving duty cycle, and the copper deposition process is accurately controlled. Optionally, the gradient adjustment of the duty cycle index can be achieved through an adaptive control algorithm, such as using a fuzzy PID controller to adjust the pulse parameters in real time in the LabVIEW FPGA module, and finally obtaining a fractal current sequence that meets the dynamic response requirements.

[0108] Furthermore, the present invention obtains the flow field data in the hole by applying a multi-order electric field to the fractal current sequence, which can systematically analyze the migration path and convection state of the plating solution ions under different electric field strengths and frequencies, accurately locate abnormal areas such as eddy currents and stagnation, reduce the risk of voids, and ensure the consistency and reliability of the hole filling process.

[0109] Among them, the in-hole flow field data refers to a set of flow state parameters of the plating solution inside the through-hole of the ceramic substrate during the pulse electroplating process, including flow velocity distribution (such as liquid flow velocity at the orifice, hole wall, and hole bottom), streamline direction, eddy current intensity, diffusion boundary layer thickness, etc. These data reflect the transmission efficiency and uniformity of copper ions in the plating solution, and directly affect the quality of copper deposition. For example, the orifice flow velocity in a certain through-hole is measured to be 0.05 cm / s and the hole bottom flow velocity is 0.01 cm / s by particle image velocimetry (PIV) technology. There is an obvious flow velocity gradient, which may lead to insufficient supply of copper ions at the bottom of the hole and form deposition defects. Optionally, the application of a multi-order electric field to the fractal current sequence can be achieved by multi-electrode array control, such as using a Keithley 2600B series source meter with a customized electrode fixture to generate a spatial gradient electric field, and finally obtaining in-hole flow field data reflecting the eddy current distribution in the hole.

[0110] Furthermore, based on the in-hole flow field data, the present invention calculates the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process, which can intuitively quantify the impact of plating solution ion transport on the deposition effect, and provide a basis for adjusting the electric field parameters and optimizing the plating solution ratio, thereby improving the accuracy of the hole filling process, reducing hole defects, and ensuring the stability of the electroplating quality of the ceramic substrate.

[0111] Among them, the dynamic hole filling process refers to the entire process in which copper ions dynamically migrate and deposit along the plating solution flow field to fill the through holes of the ceramic substrate under the action of pulse electroplating and multi-stage electric field, covering the continuous stages from the start of electroplating to the complete filling of the holes. During this process, parameters such as the plating solution flow rate, current density, and additive concentration change with time, affecting the diffusion and deposition behavior of copper ions. For example, in the electroplating of through-holes with an aspect ratio of 8:1, high-frequency and low-duty-cycle current is used in the initial stage to promote deposition at the bottom of the hole, the duty cycle is adjusted in the middle stage and a pulsed electric field is applied to enhance the disturbance of the plating solution, and the current density is reduced in the later stage to achieve smooth hole mouth. The entire dynamic regulation process is the dynamic hole filling process; the copper deposition uniformity refers to the core indicator for measuring the consistency of the copper layer deposition quality of the composite electroplating medium in the dynamic hole filling process of the through-hole of the ceramic substrate. It integrates the influence of the spatial dimension (deposition thickness difference) and the time dimension (dynamic fluctuation of the flow field) through the above formula. The closer the value is to 1, the more uniform the copper deposition at different positions and times in the hole is, which can intuitively reflect the ability of the hole filling process to control the consistency of the copper layer thickness in the entire area of ​​"hole mouth-hole wall-hole bottom".

[0112] As an embodiment of the present invention, the calculation of the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process based on the in-hole flow field data includes:

[0113] The copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process was calculated using the following formula:

[0114]

[0115] Wherein, Ud represents the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process, M represents the total number of sampling points of the flow field in the hole, j represents the number index of the sampling points, and h j The table shows the copper deposition thickness in the hole corresponding to the sampling point of the i-th data.

[0116] represents the average deposition thickness of all sampling points, T represents the total filling time corresponding to the dynamic hole filling process, represents the dispersion of the plating solution at the i-th collection point,<V(t)> It represents the average velocity modulus of the flow field in the entire hole at time t.

[0117] In detail, the copper deposition thickness in the hole refers to the actual copper plating thickness (unit: μm) measured at the jth sampling point (such as the edge of the hole, the middle of the hole wall, the center of the hole bottom, and other discrete positions) in the through-hole of the ceramic substrate after electroplating. This parameter reflects the copper deposition result at a specific spatial point and is the basic data for calculating uniformity. The h at different sampling points is j The difference directly reflects the unevenness of the deposition in the hole; the average deposition thickness refers to the arithmetic mean (unit: μm) of the copper deposition thickness of all sampling points in the hole (the total number is M), that is, As the "benchmark value" of the deposition thickness in the hole, it is used to quantify the deviation of the thickness of a single sampling point from the overall average level, and is a key reference for evaluating spatial uniformity; the total filling time refers to the total time from the start of the dynamic hole filling process (copper ion deposition begins) to the complete filling of the through-hole (or reaching the filling degree required by the process) (unit: min), which covers the complete cycle of current application, plating solution circulation, and ion deposition in the electroplating process. It is the core parameter related to "time-deposition amount-flow field change" and reflects the dynamic nature of the hole filling process; the plating solution discreteness refers to the curl of the plating solution flow velocity vector, which mathematically describes the angular velocity (unit: s) of the plating solution microelement rotating around a certain axis at the jth sampling point. -1 ), in physical terms, it reflects the "eddy / swirl intensity" of the plating solution at that point. The larger the value, the more turbulent the flow of the plating solution and the more uneven the copper ion transmission, which may lead to local deposition that is too fast (such as the eddy flow area at the orifice) or too slow (such as the stagnant flow area at the bottom of the hole). The average flow velocity modulus refers to the arithmetic mean of the modulus of the flow velocity vectors (i.e., the flow velocity size, unit: cm / s) of all sampling points in the flow field in the hole at time t of dynamic hole filling, i.e. It is used to normalize the dispersion of the plating solution (eliminating the influence of flow velocity magnitude), measure the overall "activity" of the flow field, and assist in judging the degree of interference of flow field fluctuations on deposition uniformity.

[0118] S4. Based on the copper deposition uniformity, perform a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate to obtain a copper-filled hole structure, test the residual stress in the hole of the copper-filled hole structure under high-temperature thermal cycling, and identify the lattice distortion section in the residual stress in the hole.

[0119] According to the copper deposition uniformity, the present invention performs multi-cycle electroplating-annealing iterative processing on the holes in the target ceramic substrate to obtain a copper-filled hole structure. The electroplating parameters of each round can be accurately controlled based on uniformity feedback to optimize the copper deposition distribution, and ultimately construct a dense and uniform copper-filled hole structure, thereby ensuring the electrical performance and reliability of the ceramic substrate and adapting to high-demand application scenarios.

[0120] Among them, the multi-cycle electroplating-annealing iteration refers to the process of cyclically executing the electroplating and annealing processes, which first electroplates the holes of the ceramic substrate to deposit copper, and then eliminates stress and improves the quality of the copper layer through annealing. This process is repeated to gradually optimize the hole filling effect. For example, the first round of electroplating thickens, annealing refines the grains, the second round of electroplating fills the weak areas, and then annealing is performed to achieve high-quality hole filling after multiple rounds of iteration; the copper hole filling structure refers to the copper layer morphology finally formed in the holes of the ceramic substrate after multiple cycles of electroplating-annealing iteration, which has the characteristics of uniform thickness, dense grains, low stress, etc., to ensure electrical connectivity and mechanical properties. For example, after the iteration, the thickness difference of the copper layer in the hole is less than 1μm, there is no obvious void, the grains are refined and the orientation is consistent, constructing a high-quality copper hole filling structure to meet the application requirements of the substrate.

[0121] As an embodiment of the present invention, the method of performing a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate according to the copper deposition uniformity to obtain a copper hole-filling structure includes: analyzing hole filling data corresponding to the copper deposition uniformity; determining a periodic configuration corresponding to the holes in the target ceramic substrate based on the hole filling data; querying a configuration optimization index corresponding to the periodic configuration; generating an execution sequence corresponding to the holes in the target ceramic substrate based on the configuration optimization index; and performing a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate based on the execution sequence to obtain a copper hole-filling structure.

[0122] Among them, the hole filling data refers to the copper filling state parameters in the holes of the ceramic substrate collected based on the uniformity of copper deposition, covering information such as the thickness of the copper layer in different areas, void distribution, and grain structure, reflecting the current progress and quality of the hole filling process. For example, after inspection, a hole has a copper thickness of 15μm at the hole mouth and 10μm at the hole bottom, with a thickness difference of 5μm and local micro-voids. These thickness and defect data are hole filling data, which are used to guide subsequent iterations; the cycle configuration refers to the combination of process parameters such as "electroplating time-annealing temperature-number of cycles" determined based on the hole filling data, and clarifies the operating standards for each round of iteration. For example, for the above-mentioned hole, the cycle configuration is set as: electroplating stage (current density 3A / dm 2 , duration 10min) → annealing stage (temperature 200℃, duration 5min), cycle 3 times, and fill the requirements through parameter adaptation; the configuration optimization index refers to a quantitative indicator to measure the effect of the cycle configuration on "improving copper deposition uniformity and eliminating defects", which is calculated by combining historical process data and theoretical models to reflect the optimization potential of the configuration. For example, the optimization index of the above cycle configuration is 0.85 (full score 1), indicating that the configuration can effectively reduce the hole mouth-hole bottom thickness difference (expected to drop to 2μm) and close microvoids. The higher the index, the more significant the optimization effect; the execution sequence refers to the specific operation process of decomposing the cycle configuration into the "electroplating→annealing" cycle, which includes the starting conditions, parameter settings, conversion nodes, etc. of each stage. It is an execution guide for iterative processing. For example, the execution sequence is: round 1 (electroplating 10min→annealing 5min)→uniformity detection→round 2 (repeat with the same parameters)→round 3 (adjust current density to 2.5A / dm 2 , adapted for later filling), clarify the operation logic of each step.

[0123] Furthermore, the analysis of the hole filling data corresponding to the copper deposition uniformity can be achieved through X-ray tomography, such as: using the Zeiss Xradia 520Versa system to reconstruct the three-dimensional morphology of the copper filling in the hole, and finally obtaining the hole filling data including the volume ratio; the determination of the periodic configuration corresponding to the holes in the target ceramic substrate can be achieved through process parameter optimization, such as: designing an orthogonal experimental scheme for the number of electroplating-annealing cycles through JMP software, and finally obtaining a periodic configuration that takes into account both efficiency and quality; the query of the configuration optimization index corresponding to the periodic configuration can be achieved through a multi-objective genetic algorithm, such as: solving the Pareto frontier of deposition rate and residual stress in Python's pymoo library based on NSGA-III, and finally obtaining a configuration optimization index that quantifies the process balance; the generation of the execution sequence corresponding to the holes in the target ceramic substrate can be achieved through discrete event simulation, such as: using FlexSim software to model the equipment scheduling logic of the multi-hole electroplating production line, and finally obtaining an execution sequence that minimizes the waiting time; the multi-cycle electroplating-annealing iterative processing of the holes in the target ceramic substrate can be achieved by combining process equipment, such as: using Applied Materials The Endura electroplating system is combined with the AnnealSys AS-1200 rapid annealing furnace to ultimately obtain a copper-filled hole structure without void defects.

[0124] Specifically, in order to further understand the process logic corresponding to the plating solution filling process of the copper hole filling structure in this solution, you can refer to Figure 2 It should be noted that, in the present invention, the schematic diagram of the plating solution hole filling process is used to accurately present the dynamic process of the entire cycle of plating solution hole filling from the start to the completion, which can be finely divided into stages ① to ④:

[0125] Phase ①: Display the initial state of the through-hole of the ceramic substrate. CDA (leveling agent, etc.) is adsorbed on the hole surface. Due to the electric field and flow field characteristics, CEAC (accelerator) + CDA is enriched at the bottom of the hole. The plating solution starts to flow, and copper ions begin to be transported into the hole. Phase ②: As the plating solution continues to flow, the effect of the pore mouth inhibitor (such as PEG) is stable, and the accelerator at the bottom of the hole drives the rapid deposition of copper ions, forming a "bottom-first thickening" filling trend. The hole shape gradually shrinks due to deposition. Phase ③: The deposition in the hole enters the critical necking period. The pore surface leveling agent regulates the uniformity of the surface copper layer. The accelerator at the bottom of the hole cooperates with the flow of the plating solution to promote the filling of the remaining gaps, and the deposition morphology transitions to "pore mouth-hole bottom flush"; Phase ④: The hole filling is completed, a continuous and dense copper layer is formed in the hole, the CDA on the hole surface ensures the surface flatness, and the effect of the accelerator at the bottom of the hole disappears (or is carried out by the plating solution), finally constructing a copper-filled hole structure with no voids and uniform thickness.

[0126] Through the synergistic effects of the plating solution flow direction (directional ion transmission), additive distribution (control of deposition rate), and deposition morphology evolution (from deep hole to filling), each stage fully presents the process logic of "dynamic hole filling-uniform deposition-structural densification". It is not limited by the complex influence relationship on the hole filling effect caused by factors such as substrate material and plating solution composition fluctuations in actual production (for example, when the aspect ratio is larger, the necking risk in stage ② and the difficulty of void control in stage ③ will be significantly increased).

[0127] Furthermore, by testing the residual stress in the hole of the copper-filled hole structure under high-temperature thermal cycling, the present invention can accurately understand the impact of the thermal environment on the filled hole structure, identify the hidden dangers of cracking and delamination caused by stress concentration in advance, provide a basis for optimizing the electroplating-annealing process, improve the thermal reliability of the filled hole structure, ensure the stability of the ceramic substrate under complex working conditions, adapt to high-power and high-frequency thermal cycling application scenarios, and extend the service life of the product.

[0128] The residual stress in the hole refers to the residual stress in the copper-filled hole structure in the ceramic substrate during the high-temperature thermal cycle due to the difference in thermal expansion coefficient between copper and the ceramic substrate (e.g., copper is about 17×10 -6 / ℃, ceramics about 6×10 -6 / ℃), resulting in irreversible stress at the interface and inside. This stress still partially remains after cooling to room temperature, which may cause cracking of the copper layer or delamination of the substrate. For example, after a copper-filled hole structure was thermally cycled 100 times at 260℃~15℃, the residual tensile stress at the hole wall interface measured by X-ray diffraction reached 80MPa, which exceeded the yield strength of copper (about 70MPa), and there is a risk of cracking. Optionally, the test of the residual stress in the hole of the copper-filled hole structure under high-temperature thermal cycling can be achieved by synchrotron radiation X-ray diffraction, such as: using the two-dimensional diffraction system of the BL13W1 beamline of the Shanghai Synchrotron Radiation Facility to in-situ monitor the lattice strain during the thermal cycling process, and finally obtain the residual stress in the hole with nanometer-level precision.

[0129] Furthermore, the present invention can accurately locate the microscopic area where stress is concentrated in the copper-filled hole structure by identifying the lattice distortion section in the residual stress in the hole, and quantitatively analyze the relationship between the degree of lattice distortion and residual stress, which can help build a more stable microstructure, improve the thermal fatigue resistance of the copper-filled hole structure, and ensure the reliability of the ceramic substrate under extreme working conditions.

[0130] Among them, the lattice distortion segment refers to a continuous or discontinuous spatial range composed of a local distortion core point and the stress-affected area around it, characterizing the specific distribution area of ​​lattice anomalies caused by residual stress in the hole. For example, with a local distortion core point as the center and extending outward within a range of 50 μm, the lattice offset exceeds the critical value of 2%, forming a rod-shaped distortion segment with a length of about 120 μm. This area is prone to microcracks due to stress release during thermal cycling.

[0131] As an embodiment of the present invention, the identifying of the lattice distortion segment in the residual stress in the hole includes: analyzing the stress distribution map corresponding to the residual stress in the hole; determining the critical distortion index corresponding to the lattice distortion based on the stress distribution map; dividing the distortion risk gradient corresponding to the residual stress in the hole according to the critical distortion index; extracting the local distortion core point in the distortion risk gradient; and identifying the lattice distortion segment in the residual stress in the hole based on the local distortion core point.

[0132] Among them, the stress distribution map refers to the visualization result of the spatial distribution of residual stress inside the copper-filled hole structure of the ceramic substrate measured by X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and other technologies, which presents the stress magnitude and direction in the form of cloud maps or contour lines. For example, after testing a certain hole-filled structure, the map shows that there is a red highlighted area at the edge of the hole (tensile stress>100MPa) and a blue area at the center of the hole bottom (compressive stress≈30MPa), which intuitively reflects the stress concentration position and gradient; the critical distortion index refers to the threshold parameter for measuring the degree of copper lattice distortion, which is determined by theoretical calculation or experimental calibration and is used to distinguish between "normal lattice" and "distorted lattice". For example, based on the ideal lattice constant of copper (0.3615nm), the critical distortion index is set to a lattice parameter offset of >±2%, that is, when the measured lattice constant of a certain area deviates from the ideal value by more than 0.0072nm, it is judged that the lattice is deformed. It is defined as the lattice distortion area; the distortion risk gradient refers to dividing the residual stress in the hole into gradient intervals of different risk levels according to the critical distortion index, reflecting the severity of the lattice distortion and the potential failure risk. For example, it is divided into three levels: low risk (lattice offset ≤ 1%), medium risk (1% < offset ≤ 2%), and high risk (offset > 2%), and the corresponding stress levels are < 60MPa, 60-100MPa, and > 100MPa, respectively. The higher the gradient, the easier it is to induce cracking; the local distortion core point refers to the microscopic core position where the stress concentration is most significant and the lattice distortion is most severe in the distortion risk gradient, usually the geometric mutation of the pore structure (such as the pore corners, micropore edges) or the material interface defect. For example, the sharp edge of the pore chamfer radius of 0.05mm, due to stress concentration, the lattice offset measured is 3.5%, which becomes the local distortion core point and the origin position of crack initiation.

[0133] Furthermore, the analysis of the stress distribution map corresponding to the residual stress in the hole can be achieved through a full-field strain reconstruction algorithm, such as using DICe digital image correlation software to process synchrotron radiation diffraction data, and ultimately obtaining a stress distribution map with submicron resolution; the determination of the critical distortion index corresponding to the lattice distortion can be achieved through molecular dynamics simulation, such as calculating the copper lattice energy barrier mutation point based on LAMMPS software, and ultimately obtaining the critical distortion index of the dislocation nucleation threshold; the division of the distortion risk gradient corresponding to the residual stress in the hole can be achieved through K-means clustering analysis, such as using Pyt Hon's scikit-learn library performs unsupervised classification on stress gradients, and ultimately obtains a three-level divided distortion risk gradient; the extraction of local distortion core points in the distortion risk gradient can be achieved through topological data analysis, such as: calculating the continuous homology characteristics of the stress field through the JavaPlex toolkit, and ultimately obtaining local distortion core points in the high-dimensional manifold; the identification of lattice distortion segments in the residual stress in the hole can be achieved through convolutional neural networks, such as: using the U-Net architecture to segment the EBSD orientation difference map under the PyTorch framework, and ultimately obtaining dislocation-intensive lattice distortion segments.

[0134] S5. Generate a crystallization-annealing curve corresponding to the copper hole-filling structure according to the lattice distortion segment, extract key inflection points in the crystallization-annealing curve, analyze control data corresponding to the key inflection points, and formulate a process optimization plan corresponding to the copper hole-filling structure based on the control data.

[0135] The present invention generates a crystallization-annealing curve corresponding to the copper hole-filling structure based on the lattice distortion section, can accurately design annealing temperature-time parameters for the microscopic defects (such as dislocations and grain boundary stress) in the distortion area, and directionally repair lattice damage. It can provide differentiated annealing schemes for multi-cycle electroplating-annealing processes, improve the microstructural consistency and thermal stability of the hole-filling structure, and enhance fatigue resistance.

[0136] The crystallization-annealing curve is a curve that depicts the change of current density in the electrodeposition stage and the temperature-time program in the annealing stage with time as the horizontal axis, and is used to dynamically control the copper crystallization process and stress release. For example, the curve shows: 0-20min electrodeposition (current density from 3A / dm 2 Gradient down to 2A / dm 2 )→20-25min annealing (temperature increased from room temperature to 220°C and kept at this temperature for 5min). Through the combination of “slow deposition + high temperature annealing”, the grain refinement of the distorted section is promoted and the lattice stress is reduced by more than 30%.

[0137] As an embodiment of the present invention, generating a crystallization-annealing curve corresponding to the copper hole-filling structure based on the lattice distortion segment includes: marking the segment stress distribution corresponding to the lattice distortion segment; dividing the filling adaptation area corresponding to the segment stress distribution; querying the regional control index in the filling adaptation area; based on the regional control index, controlling the electrodeposition rate corresponding to the copper hole-filling structure; and generating a crystallization-annealing curve corresponding to the copper hole-filling structure based on the electrodeposition rate.

[0138] Among them, the segment stress distribution refers to the spatial size, direction and gradient distribution characteristics of the residual stress in the lattice distortion segment, which is quantified by stress testing technology (such as X-ray diffraction). For example, in a certain distortion segment, the edge of the hole mouth presents a tensile stress of 120MPa, which decreases by 30MPa every 100μm along the hole depth direction, and there is a compressive stress of 40MPa in the transition zone at the bottom of the hole, forming a "tensile-compressive" stress gradient distribution map, reflecting the correlation between lattice distortion and stress concentration; the filling adaptation area refers to dividing the lattice distortion segment into several process adaptation intervals according to the segment stress distribution, and each area corresponds to specific electrodeposition and annealing parameter requirements. For example, the high stress area (tensile stress>100MPa) is divided into a "slow deposition area", the medium stress area (50-100MPa) is a "balanced area", and the low stress area (<50MPa) is a "fast filling area". Each section is adapted to different current densities and annealing temperatures. The regional control index refers to a quantitative indicator that measures the sensitivity of the filling adaptation area to the electrodeposition rate. It is obtained by fitting historical process data and is used to guide the direction of parameter adjustment. For example, the control index of the slow deposition area is -0.8 (negative correlation), which means that the current density decreases by 0.1A / dm 2 , the stress in this section can be reduced by 8MPa; the control index of the equilibrium zone is -0.3, and the parameters need to be slightly adjusted to avoid overfilling; the electrodeposition rate refers to the deposition thickness of copper ions in the pores of the ceramic substrate per unit time (unit: μm / min), which is determined by parameters such as current density and plating solution concentration. For example, under standard working conditions, the current density is 3A / dm 2 Corresponding to a deposition rate of 1.2 μm / min, according to the regional control index, the slow deposition zone reduces the current density to 2.5 A / dm 2 , the deposition rate is then reduced to 1.0 μm / min, reducing stress accumulation.

[0139] Furthermore, the marking of the segment stress distribution corresponding to the lattice distortion segment can be achieved through finite element sub-modeling technology, such as: using the sub-modeling function of ANSYS Workbench to perform local mesh encryption on the distortion area, and finally obtaining a high-precision segment stress distribution; the division of the filling adaptation area corresponding to the segment stress distribution can be achieved through Voronoi diagram segmentation, such as: using MATLAB's voronoi function to generate Thiessen polygons based on stress extreme points, and finally obtaining a filling adaptation area of ​​the stress adaptive partition; the querying of the regional control index in the filling adaptation area can be achieved through response surface optimization, such as: establishing a multi-objective optimization model of stress-process parameters through ModeFRONTIER software, and finally obtaining a regional control index that quantifies the control effect; the control of the electrodeposition rate corresponding to the copper filling structure can be achieved through adaptive pulse electroplating, such as: using a PulseR waveform generator to dynamically adjust the current density according to online stress feedback, and finally obtaining a stress-balanced electrodeposition rate; the generation of the crystallization-annealing curve corresponding to the copper filling structure can be achieved through differential scanning calorimetry, such as: using NETZSCH DSC The 214Polyma analyzer monitors the exothermic peak of copper grain recrystallization and ultimately obtains the crystallization-annealing curve for the optimized process window.

[0140] By extracting the key inflection points in the crystallization-annealing curve and analyzing the control data corresponding to the key inflection points, the present invention can accurately locate the key turning points of the electrodeposition and annealing processes (such as the current density mutation point and the annealing temperature peak), quantitatively evaluate the impact of parameter adjustment on lattice distortion, achieve precise control of the microstructure and stress state of the pore-filling structure, and ensure process stability.

[0141] The key inflection point refers to the key time node in the crystallization-annealing curve that reflects the sudden change of process parameters or state transition, which usually corresponds to the significant change point of electrodeposition rate or annealing temperature. It is the core control point that affects the microstructure and stress state of copper filling structure. For example, in the curve, "the current density at the 15th minute changes from 3A / dm 2 Drops to 2A / dm 2 ", or the platform starting point of "annealing temperature reaches a peak of 220℃ and maintains constant temperature at the 30th minute", are all key inflection points, and their parameter settings directly affect the lattice distortion repair effect; the control data refers to the process parameter and physical performance data set collected around the key inflection points, including the current density, deposition rate, stress value in the electrodeposition stage, and the temperature, holding time, grain size, etc. in the annealing stage, which are used to analyze the rationality of the process adjustment at the inflection point. For example, at the "current density drops sharply" inflection point, the control data include: the current density before / after adjustment (3A / dm 2 →2A / dm 2), the corresponding deposition rate change (1.2μm / min→1.0μm / min), the stress drop within 10 minutes after adjustment (from 110MPa to 95MPa), and the actual effect of parameter adjustment on reducing lattice stress is evaluated through data association. Optionally, the above can be achieved through differential signal processing, such as: using OriginLab software to perform Savitzky-Golay filtering and then derivative, and finally obtaining the key inflection point that identifies the grain growth transition temperature; the analysis of the control data corresponding to the key inflection point can be achieved through partial least squares regression, such as: using SIMCA software to establish a multivariate model of inflection point parameters and process conditions, and finally obtaining the control data with collinearity removed.

[0142] Based on the control data, the present invention formulates a process optimization plan corresponding to the copper hole-filling structure. Relying on the correlation analysis of measured parameters, stress, and deposition effects, key parameters such as electrodeposition rate and annealing temperature can be adjusted in a targeted manner to achieve precise process adaptation, improve the stability and repeatability of the electroplating-annealing process, and ensure the consistency and reliability of the hole-filling quality of the ceramic substrate.

[0143] Among them, the process optimization plan refers to a systematic solution covering parameter adjustment, process improvement and equipment optimization based on the in-depth analysis of the weak links of the copper hole filling structure in the electroplating-annealing process based on the control data. The plan aims to improve the uniformity of copper deposition and reduce residual stress. By adjusting the current density curve and optimizing the annealing temperature sequence, the process can be precisely controlled. For example, if the control data shows that the lattice distortion in the bottom area of ​​the hole is serious, the process optimization plan can be set as follows: reduce the current density to 2A / dm in the middle of the electroplating process. 2 The deposition time is extended, the annealing temperature is increased from 200°C to 220°C, and the holding time is increased by 3 minutes. The quality of the copper layer at the bottom of the hole is improved through step-by-step control. Optionally, the process optimization plan corresponding to the copper filling structure can be achieved through a multi-objective optimization algorithm, such as: using the NSGA-III genetic algorithm to collaboratively optimize the deposition rate and residual stress under the Python pymoo framework, and finally obtaining the Pareto optimal frontier process optimization plan.

[0144] Compared with the problems described in the background technology, the present invention can accurately adapt to the characteristics of through-holes of different specifications by obtaining the through-hole structural parameters corresponding to the target ceramic substrate, and can perform targeted ratio optimization on the prefabricated electroplating solution, and can also provide an important basis for the subsequent selection of pulse current waveforms, monitoring and regulation of the electroplating process, thereby effectively avoiding problems such as uneven coating and voids in the holes. The present invention can obtain key data such as hole mouth accumulation thickness and hole bottom coverage in real time by monitoring the copper deposition morphology of the holes in the target ceramic substrate during the pulse electroplating process, providing an intuitive basis for accurately regulating electroplating parameters and optimizing the deposition process, and effectively improving the controllability and consistency of hole filling quality. Furthermore, based on the polarization effect coefficient, the present invention optimizes the duty cycle index in the pulse current waveform, can accurately adapt to the characteristics of the composite electroplating medium, dynamically balance the difference in deposition between the hole mouth and the hole bottom, and suppress polarization anomalies. It helps to build a more stable and efficient pulse electroplating process and improve the quality and reliability of ceramic substrate hole filling. Furthermore, the present invention performs multi-cycle electroplating-annealing iterative processing on the holes in the target ceramic substrate according to the copper deposition uniformity to obtain a copper hole filling structure. It can accurately control the electroplating parameters of each round based on the uniformity feedback, optimize the copper deposition distribution, and finally construct a dense and uniform copper hole filling structure to ensure the electrical performance and reliability of the ceramic substrate and adapt to high-demand application scenarios. Finally, the present invention generates a crystallization-annealing curve corresponding to the copper hole filling structure according to the lattice distortion section. It can accurately design the annealing temperature-time parameters for the microscopic defects (such as dislocations and grain boundary stresses) in the distortion area, and repair the lattice damage in a direction. It can provide differentiated annealing schemes for multi-cycle electroplating-annealing processes, improve the microstructural consistency and thermal stability of the hole filling structure, and enhance fatigue resistance. Therefore, the ceramic substrate through-hole electroplating copper filling process control method provided in the embodiment of the present invention can improve the reliability of the through-hole electroplating copper filling process.

[0145] Example 2:

[0146] like Figure 3 The figure shows a functional module diagram of a ceramic substrate through-hole electroplating copper filling process control system according to the present invention.

[0147] The ceramic substrate through-hole copper plating filling process control system 200 described in the present invention can be installed in an electronic device. Depending on the functionality implemented, the control system can include a waveform query module 201, a coefficient calculation module 202, a uniformity calculation module 203, a segment identification module 204, and a plan formulation module 205. A module, also referred to as a unit, is a series of computer program segments that can be executed by an electronic device processor and perform a fixed function. These modules are stored in the electronic device's memory.

[0148] In the embodiment of the present invention, the functions of each module / unit are as follows:

[0149] The waveform query module 201 is used to obtain the through-hole structural parameters corresponding to the target ceramic substrate, optimize the ratio of the prefabricated electroplating solution based on the through-hole structural parameters to obtain a proportioned electroplating solution, analyze the composite electroplating medium corresponding to the proportioned electroplating solution, and query the pulse current waveform corresponding to the composite electroplating medium;

[0150] The coefficient calculation module 202 is used to monitor the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process, extract the pore opening accumulation thickness and pore bottom coverage corresponding to the copper deposition morphology, and calculate the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore opening accumulation thickness and pore bottom coverage;

[0151] The uniformity calculation module 203 is configured to optimize the duty cycle index in the pulse current waveform based on the polarization effect coefficient, perform gradient adjustment on the duty cycle index to obtain a fractal current sequence, apply a multi-order electric field to the fractal current sequence to obtain in-hole flow field data, and calculate the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process based on the in-hole flow field data;

[0152] The segment identification module 204 is configured to perform a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate according to the copper deposition uniformity to obtain a copper-filled hole structure, test the residual stress in the hole of the copper-filled hole structure under high-temperature thermal cycling, and identify a lattice distortion segment in the residual stress in the hole;

[0153] The solution formulation module 205 is used to generate a crystallization-annealing curve corresponding to the copper hole-filling structure according to the lattice distortion segment, extract key inflection points in the crystallization-annealing curve, analyze the control data corresponding to the key inflection points, and formulate a process optimization solution corresponding to the copper hole-filling structure based on the control data.

[0154] In detail, the modules in the ceramic substrate through-hole electroplating copper filling process control system 200 described in the embodiment of the present invention are used in the same manner as above. Figure 1 The same technical means as the ceramic substrate through-hole electroplating copper filling process control method described in the and can produce the same technical effects, will not be repeated here.

[0155] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for controlling a through-hole copper plating filling process of a ceramic substrate, characterized in that: The method comprises: Obtaining through-hole structural parameters corresponding to a target ceramic substrate, optimizing the ratio of a prefabricated electroplating solution based on the through-hole structural parameters to obtain a proportioned electroplating solution, analyzing a composite electroplating medium corresponding to the proportioned electroplating solution, and querying a pulse current waveform corresponding to the composite electroplating medium; monitoring the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process, extracting the pore opening accumulation thickness and pore bottom coverage corresponding to the copper deposition morphology, and calculating the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore opening accumulation thickness and pore bottom coverage; Based on the polarization effect coefficient, optimizing the duty cycle index in the pulse current waveform, gradient-adjusting the duty cycle index to obtain a fractal current sequence, applying a multi-order electric field to the fractal current sequence to obtain in-hole flow field data, and calculating the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process based on the in-hole flow field data; Based on the copper deposition uniformity, performing a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate to obtain a copper-filled hole structure, testing the residual stress in the hole of the copper-filled hole structure under high-temperature thermal cycling, and identifying a lattice distortion section in the residual stress in the hole; According to the lattice distortion section, a crystallization-annealing curve corresponding to the copper hole-filling structure is generated, key inflection points in the crystallization-annealing curve are extracted, and control data corresponding to the key inflection points are analyzed. Based on the control data, a process optimization plan corresponding to the copper hole-filling structure is formulated.

2. A ceramic substrate through-hole copper plating filling process control method according to claim 1, characterized in that: The method of optimizing the ratio of the prefabricated electroplating solution based on the through-hole structure parameters to obtain the ratio of the electroplating solution comprises: Analyzing electroplating constraints corresponding to the through-hole structural parameters; determining candidate plating solution compositions under the electroplating constraints; Analyze the plating solution ratio and composition corresponding to the prefabricated electroplating solution; Compatibly combining the plating solution ratio components with the optimized ratio components to obtain a plating solution ratio; Based on the plating solution combination ratio, the prefabricated electroplating solution is optimized to obtain a proportioned electroplating solution.

3. A ceramic substrate through-hole copper plating filling process control method according to claim 1, characterized in that: The analyzing the composite electroplating medium corresponding to the proportioned electroplating solution includes: collecting electrochemical signals of the proportioned electroplating solution during the electrodeposition process; Extracting a deposition characteristic sequence corresponding to the electroplating solution based on the electrochemical signal; Determining a deposition threshold interval corresponding to the electroplating solution according to the deposition characteristic sequence; analyzing the ratio-deposition relationship in the deposition threshold interval; Based on the ratio-deposition relationship, the composite electroplating medium corresponding to the ratio of the electroplating solution is analyzed.

4. A ceramic substrate through-hole copper plating filling process control method according to claim 1, characterized in that: The monitoring of the copper deposition morphology of the pores in the target ceramic substrate during the pulse electroplating process includes: Obtaining pulse plating parameters required for holes in the target ceramic substrate; Based on the pulse electroplating parameters, collecting current distribution data in the holes in the target ceramic substrate; Analyzing abnormal area characteristics corresponding to the current distribution data; Based on the abnormal area characteristics, querying the critical process threshold corresponding to the holes in the target ceramic substrate; The copper deposition morphology of the holes in the target ceramic substrate during the pulse electroplating process is monitored according to the critical process threshold.

5. The method for controlling a through-hole copper plating filling process of a ceramic substrate according to claim 1, wherein: The calculating of the polarization effect coefficient of the composite electroplating medium at different current densities based on the pore opening accumulation thickness and the pore bottom coverage includes: The polarization effect coefficient of the composite electroplating medium at different current densities was calculated using the following formula: Wherein, Jα represents the polarization effect coefficient of the composite electroplating medium at different current densities, t represents the cumulative electroplating time, d represents the through-hole depth, n represents the total number of sampling points of current density, i represents the number index of sampling points, ΔE i represents the change in polarization potential at the i-th sampling point, C i represents the bottom coverage of the ith sampling point, H i represents the orifice accumulation thickness at the i-th sampling point, Δj i Indicates the change in current density at the i-th sampling point, H th represents the thickness threshold of the orifice accumulation thickness, λ represents the comprehensive coordination factor, β represents the correction coefficient corresponding to the current density, and j i Represents the current density value of the i-th sampling point.

6. A ceramic substrate through-hole electroplating copper filling process control method according to claim 1, characterized in that: Optimizing the duty cycle index in the pulse current waveform based on the polarization effect coefficient includes: Based on the polarization effect coefficient, collecting historical duty cycle data corresponding to the pulse current waveform; Analyzing polarization response characteristics corresponding to the historical duty cycle data; Determining a duty cycle optimization direction corresponding to the pulse current waveform based on the polarization response characteristics; Extracting a duty cycle adjustment point corresponding to the pulse current waveform according to the duty cycle optimization direction; Based on the duty cycle adjustment point, a duty cycle index in the pulse current waveform is optimized.

7. A ceramic substrate through-hole electroplating copper filling process control method according to claim 1, characterized in that: The calculating, based on the in-hole flow field data, the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process comprises: The copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process was calculated using the following formula: Wherein, Ud represents the copper deposition uniformity of the composite electroplating medium during the dynamic hole filling process, M represents the total number of sampling points of the flow field in the hole, j represents the number index of the sampling points, and h j The table shows the copper deposition thickness in the hole corresponding to the sampling point of the i-th data. represents the average deposition thickness of all sampling points, T represents the total filling time corresponding to the dynamic hole filling process, represents the dispersion of the plating solution at the i-th collection point,<V(t)> It represents the average velocity modulus of the flow field in the entire hole at time t.

8. A ceramic substrate through-hole copper plating filling process control method according to claim 1, characterized in that: The method further comprises: performing a multi-cycle electroplating-annealing iterative process on the holes in the target ceramic substrate according to the copper deposition uniformity to obtain a copper hole-filling structure, comprising: analyzing hole filling data corresponding to the copper deposition uniformity; determining a periodic configuration corresponding to the holes in the target ceramic substrate based on the hole filling data; Query the configuration optimization index corresponding to the periodic configuration; generating an execution sequence corresponding to the holes in the target ceramic substrate based on the configuration optimization index; Based on the execution sequence, a multi-cycle electroplating-annealing iterative process is performed on the holes in the target ceramic substrate to obtain a copper hole-filling structure.

9. A ceramic substrate through-hole electroplating copper filling process control method according to claim 1, characterized in that: The identifying of the lattice distortion section in the residual stress in the hole comprises: Analyzing a stress distribution map corresponding to the residual stress in the hole; Determining a critical distortion index corresponding to the lattice distortion based on the stress distribution map; According to the critical distortion index, dividing the distortion risk gradient corresponding to the residual stress in the hole; extracting local distortion core points in the distortion risk gradient; Based on the local distortion core points, lattice distortion sections in the residual stress within the hole are identified.

10. The method for controlling a through-hole copper plating filling process of a ceramic substrate according to claim 1, wherein: Generating a crystallization-annealing curve corresponding to the copper hole-filling structure according to the lattice distortion section includes: Marking the stress distribution of the section corresponding to the lattice distortion section; Dividing the filling adaptation area corresponding to the stress distribution of the segment; Querying the regional regulation index in the filling adaptation area; Based on the regional regulation index, regulating the electrodeposition rate corresponding to the copper hole-filling structure; A crystallization-annealing curve corresponding to the copper hole-filling structure is generated based on the electrodeposition rate.

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