DOE test method for packaging assembly warping simulation

Abstract

The invention discloses a DOE test method for warping simulation of a packaging assembly. The method comprises the following steps: establishing a simplified equivalent three-dimensional simulation model based on an actual packaging structure of a device; setting model boundary conditions to operate simulation so as to establish a to-be-optimized parameter group; establishing a DOE test according to the to-be-optimized parameter group; the method comprises the following steps: preliminarily determining the influence of each influence factor on the warping degree of a packaging assembly according to a DOE test result, establishing a refined to-be-optimized parameter group according to the numerical change rate of different influence factors on warping effect evaluation parameters and the requirements of an actual production process, and establishing an accurate three-dimensional simulation model based on an actual packaging structure of a device according to the DOE test; and setting boundary conditions of the accurate three-dimensional simulation model, running simulation, outputting a calculation result of the accurate three-dimensional simulation model, determining an optimal solution of each parameter again according to the numerical change rate of the warping effect evaluation parameters obtained by the accurate three-dimensional simulation model and actual production process requirements, and outputting a final optimal parameter result.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor packaging technology, and in particular to a DOE test method for warpage simulation of packaging components. Background Art

[0002] With the rapid development of industries such as automobiles, consumer electronics, 5G technology and data centers, the demand for high-density, multi-functional and high-reliability electronic devices has been driven. Advanced electronic packaging technology based on ball grid array (BGA) has become a prominent direction for the development of the semiconductor industry. However, the warpage problem is still a common problem in this field, which can seriously damage the accuracy and automation of subsequent processes, thereby triggering various operations. Therefore, a comprehensive inspection of warpage is essential to improve the yield of package assembly and ensure device reliability.

[0003] Package components are usually composed of a semiconductor material substrate mainly composed of silicon, and a dielectric layer and metal wiring distributed on it. Therefore, there are large differences in thermal expansion coefficients and mechanical properties between different materials in the package components, resulting in a large warpage of the package components when subjected to thermal stress (such as reflow, stress shock). Warpage deformation will not only destroy the subsequent packaging process, but also cause various reliability problems, such as micro-mold cracking, delamination under the filling layer, and solder bump fatigue failure caused by high residual stress.

[0004] At present, the research on package warpage is more focused on analyzing the failure causes and influencing factors of actual samples, which will greatly increase the R&D cost and construction period. Therefore, warpage prediction is an indispensable part of the package design process. However, there are relatively few research patents on warpage prediction. Conventional warpage prediction mainly optimizes the design under different simulation software, simulation environment and simulation model, but it still requires a large investment of human resources and computer resources.

[0005] Figure 1 FIG. 1 is a schematic diagram of a device for reducing the warpage of a packaged chip in the prior art. Figure 1As shown, the invention patent with application publication number CN115659895A discloses a method, device, storage medium and electronic device for reducing the warpage of packaged chips. Based on the extracted sample points, two or more different proxy models are constructed to form a combined model. The advantages of different proxy models can be combined in the form of combined proxy models to improve the modeling accuracy and the accuracy of optimized design. Finally, the combined model is solved by particle swarm algorithm, which can output the best chip spacing and package thickness for design, and reduce the problem of excessive warpage in the packaging process. However, this solution needs to form a combined model by continuously adding different proxy models to improve the model prediction accuracy. Each time a proxy model is added, an error value calculation is required to confirm that the prediction accuracy meets the requirements. In the process of building the model, a great deal of computing power is required, and there are great requirements for computing equipment and technical capabilities. In addition, the key to the early prediction of the warpage of the packaged component of this solution is to adjust the package structure material so that the device warpage meets the production requirements. However, for different package sizes and structural materials, the influencing factors are also different. Summary of the invention

[0006] To solve the above problems, the purpose of the present invention is to provide a DOE (Design of Experiment) test method for packaging component warpage simulation, which screens the influencing factors and their numerical ranges through a simple equivalent model in the early stage, and then determines the packaging component structure material parameters that meet the production process through a DOE test, and optimizes the packaging structure and material parameters according to the simulation results to reduce and effectively control the wafer warpage. In this way, the present invention can simplify the packaging component prediction steps and improve the prediction accuracy.

[0007] To achieve the above object, the present invention provides a DOE test method for packaging component warpage simulation, which includes:

[0008] Step S1: establishing a simplified equivalent three-dimensional simulation model based on the actual packaging structure of the device, including: creating a three-dimensional model corresponding to each structure in the packaging component, converting the created three-dimensional model into a format recognizable by the electronic product warpage analysis simulation environment and importing it into the simulation environment to form a three-dimensional simulation model, and finally setting material parameters of each part of the structure of the three-dimensional simulation model;

[0009] Step S2: Setting the model boundary conditions and running the simulation to establish the parameter group to be optimized, specifically including:

[0010] Step S201: setting model boundary conditions, wherein the model boundary conditions include working environment temperature, analysis steps and time, thermal conditions, fixed point constraints and / or displacement constraints;

[0011] Step S202: Divide the model into grids;

[0012] Step S203: running the simulation, outputting the model calculation results of the simplified equivalent three-dimensional simulation model, and determining the warpage evaluation parameters and the parameter group to be optimized according to the model calculation results;

[0013] Step S3: establishing a DOE test according to the parameter group to be optimized, specifically assigning values ​​to each parameter in the parameter group to be optimized one by one, determining the optimal solution of each parameter according to the numerical change of the warping effect evaluation parameter, and outputting the optimal parameter result, wherein the numerical change of the warping effect evaluation parameter refers to the rate of change of the numerical value;

[0014] Step S4: preliminarily determine the influence of various influencing factors on the warpage of the package component according to the DOE test results, establish a detailed DOE test based on the numerical change rate of the warpage effect evaluation parameter of different influencing factors and the requirements of the actual production process, and establish an accurate three-dimensional simulation model based on the actual package structure of the device according to the DOE test;

[0015] Step S5: Set the boundary conditions of the precise three-dimensional simulation model, run the simulation and output the calculation results of the precise three-dimensional simulation model, determine the optimal solution of each parameter again according to the numerical change rate of the warping effect evaluation parameter obtained by the precise three-dimensional simulation model and the actual production process requirements, and output the final optimal parameter results.

[0016] In one embodiment of the present invention, in step S1, the simplified equivalent three-dimensional simulation model is a 1:1 simplified equivalent modeling based on the package component to be simulated, which calculates the material parameters of each part of the structure of the three-dimensional simulation model according to the equivalent formula, wherein the equivalent formula includes:

[0017] The equivalent formula in the horizontal direction is: equi_parallel =βk 1 +(1-β)k 2 ;

[0018] The equivalent formula in the vertical direction is:

[0019] In the formula, k 1 and k 2 are the material performance parameters of the first material and the second material respectively, and β is the volume fraction of the first material.

[0020] In one embodiment of the present invention, the model calculation result in step S203 includes:

[0021] The stress distribution cloud diagram and the warpage of each structure of the simplified equivalent three-dimensional simulation model according to step S1;

[0022] According to the stress distribution, the warpage of the substrate in the simplified equivalent three-dimensional simulation model is used as the warpage effect evaluation parameter;

[0023] The parameter group to be optimized is set based on public literature data and existing engineering experience.

[0024] In one embodiment of the present invention, step S3 specifically includes:

[0025] Step S301: using the initial values ​​of each packaging component in the simplified equivalent three-dimensional simulation model as a reference, recording the change in substrate warpage when the core layer has different thicknesses, so as to obtain the optimal solution of the first parameter;

[0026] Step S302: using the optimal solution of the first parameter as the initial value, recording the change in the warpage of the substrate when the package size of the heat dissipation cover is different, thereby obtaining the optimal solution of the second parameter;

[0027] Step S303: using the optimal solution of the second parameter as the initial value, recording the change in the warpage of the substrate when the thickness of the heat dissipation cover is different, so as to obtain the optimal parameter result.

[0028] In one embodiment of the present invention, the step S4 of establishing an accurate three-dimensional simulation model based on the actual packaging structure of the device includes:

[0029] Create a three-dimensional model corresponding to each structure within the package component;

[0030] Convert the created 3D model into a format that can be recognized by the electronic product warpage analysis simulation environment and import it into the simulation environment to form an accurate 3D simulation model;

[0031] Set material properties for each part of the structure for accurate 3D simulation models.

[0032] In one embodiment of the present invention, step S5 specifically includes:

[0033] Step S501: setting boundary conditions of the accurate three-dimensional simulation model, wherein the boundary conditions include working environment temperature, analysis steps and time, thermal conditions, fixed point constraints and / or displacement constraints, etc.;

[0034] Step S502: finely divide the model into grids by region;

[0035] Step S503: Run the simulation, output the calculation results of the accurate three-dimensional simulation model, and determine the warpage evaluation parameters and the parameter group to be optimized according to the calculation results; wherein the calculation results include: the stress distribution cloud map and the warpage of each structure according to the accurate three-dimensional simulation model; according to the stress distribution, the warpage of the substrate in the accurate three-dimensional simulation model is used as the warpage effect evaluation parameter;

[0036] Step S504: determining the optimal solution of each parameter according to the numerical change rate of the warping effect evaluation parameter and the actual production process requirements, and outputting the final optimal parameter result.

[0037] In one embodiment of the present invention, the meshing in steps S202 and S502 is performed by dragging the shell unit / solid surface mesh to divide the common node mesh from bottom to top, and then dividing other component meshes by dragging the solid unit surface upward.

[0038] Compared with the prior art, the DOE test method for packaging component warpage simulation provided by the present invention establishes a simplified equivalent model and actual process conditions to establish a DOE test, performs pre-simulation of the warpage of the packaging component before the process flow, and optimizes the packaging structure and material parameters accordingly based on the simulation results. This not only saves a lot of human resources and computer resources spent on early simulation, but is also suitable for packaging components of various packaging sizes and structural materials, and can obtain precise simulation results more accurately and quickly, thereby achieving the purpose of early warpage prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A schematic diagram of a device for reducing the warpage of a packaged chip in the prior art;

[0041] Figure 2 A schematic diagram of a flow chart of an embodiment of the present invention;

[0042] Figure 3 is a cross-sectional view of a simplified equivalent three-dimensional simulation model in one embodiment of the present invention;

[0043] Figure 4A and Figure 4B A schematic diagram of a stress distribution cloud diagram and warpage of each structure of a simplified equivalent three-dimensional simulation model in one embodiment of the present invention;

[0044] Figure 5A and Figure 5B A simplified equivalent three-dimensional simulation model in one embodiment of the present invention is a substrate warpage variation trend diagram under core layers of different thicknesses;

[0045] Fig. 6A and Figure 6BA graph showing a change trend of substrate warpage under heat dissipation cover packages of different sizes in a simplified equivalent three-dimensional simulation model in one embodiment of the present invention;

[0046] Fig. 7A and Figure 7B It is a graph showing the variation trend of substrate warpage under heat dissipation covers of different thicknesses in a simplified equivalent three-dimensional simulation model in one embodiment of the present invention.

[0047] Explanation of the accompanying drawings: 1~ABF-Bottom equivalent layer; 2~ABF-Top equivalent layer; 3~Core equivalent layer; 4-solder ball and bottom filling equivalent layer; 5-chip; 6~thermal conductive interface material; 7~heat sink cover; 8~heat sink cover sealing glue; S1~S5-steps. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] In the semiconductor manufacturing process, warping deformation will not only destroy the subsequent packaging process, but also cause various reliability problems, such as micro-mold cracking, delamination under the filling layer, and fatigue failure of solder bumps caused by high residual stress. At present, the research on package warping is more about analyzing the failure causes and influencing factors of actual samples, which will greatly increase the R&D cost and construction period. Conventional package component warping prediction is to perform simulation tests on the designed package components to verify whether the device warping meets the production process requirements. However, different package sizes and structural materials have different influencing factors. Directly modeling and simulating the package components will increase the initial construction period investment and affect the accuracy of the simulation results. The present invention screens the influencing factors by simplifying the model, and then determines the package component structural materials that meet the production process through DOE experiments, and finally adjusts the package structural materials so that the device warping meets the production requirements.

[0050] Figure 2 is a flow chart of an embodiment of the present invention, Figure 3 is a cross-sectional view of a simplified equivalent three-dimensional simulation model in one embodiment of the present invention, such as Figure 2 and Figure 3 As shown, this embodiment provides a DOE test method for packaging component warpage simulation, which includes:

[0051] Step S1: establishing a simplified equivalent three-dimensional simulation model based on the actual packaging structure of the device, including: creating a three-dimensional model corresponding to each structure in the packaging component, converting the created three-dimensional model into a format recognizable by the electronic product warpage analysis simulation environment and importing it into the simulation environment to form a three-dimensional simulation model, and finally setting material parameters of each part of the structure of the three-dimensional simulation model;

[0052] In this embodiment, in step S1, the simplified equivalent three-dimensional simulation model is a 1:1 simplified equivalent modeling based on the package component to be simulated, which calculates the material parameters of each part of the structure of the three-dimensional simulation model according to the equivalent formula, wherein the equivalent formula includes:

[0053] The equivalent formula in the horizontal direction is: equi_parallel =βk 1 +(1-β)k 2 ;

[0054] The equivalent formula in the vertical direction is:

[0055] In the formula, k 1 and k 2 are the material performance parameters of the first material and the second material respectively, and β is the volume fraction of the first material.

[0056] by Figure 3 For example, the structure of the packaging component in this embodiment includes ABF-Bottom (the substrate is the bottom plate of ABF (Ajinomoto deposition film)) equivalent layer 1, ABF-Top (the substrate is the top plate of ABF) equivalent layer 2, Core (the core layer of the substrate) equivalent layer 3, solder ball and bottom filling (ball & underfill) equivalent layer 4, chip (Die) 5, thermal interface material (TIM) 6, heat dissipation cover (Lid) 7 and heat dissipation cover sealing glue (Lid adhesive) 8. This embodiment reduces the cost of accurate modeling and simulation calculation while ensuring the accuracy of simulation results by establishing a simplified equivalent model and calculating equivalent material characteristic parameters.

[0057] Step S2: Setting the model boundary conditions and running the simulation to establish the parameter group to be optimized, specifically including:

[0058] Step S201: setting model boundary conditions, which include working environment temperature, analysis steps and time, thermal conditions, fixed point constraints, and displacement constraints;

[0059] Among them, in an embodiment of the present invention, during actual simulation, the working environment temperature can be set to 150°C, the cooling method can be set to air convection, the lower right corner of the substrate can be set to a fixed point constraint, the point adjacent to the fixed point in the X direction can be set to an X-direction free displacement constraint, and the point at a 45° diagonal direction with the fixed point can be set to an X, Y direction free displacement constraint. In other embodiments, other settings can be made according to requirements, and the present invention is not limited to this.

[0060] Step S202: Divide the model into grids;

[0061] Since the packaging structure is relatively regular, in this embodiment, the common node grid can be divided from bottom to top by dragging the shell unit / solid surface grid, and then other component grids can be divided upward by dragging the solid unit surface. Each layer of component thickness is divided into 2 layers of units; finally, the relevant nodes are merged by checking the overlapping nodes, where the grid base size is 0.5mm.

[0062] Step S203: running the simulation, outputting the model calculation results of the simplified equivalent three-dimensional simulation model, and determining the warpage evaluation parameters and the parameter group to be optimized according to the model calculation results;

[0063] In this embodiment, the model calculation results in step S203 include:

[0064] The stress distribution cloud diagram and the warpage of each structure of the simplified equivalent three-dimensional simulation model according to step S1;

[0065] According to the stress distribution, the warpage of the substrate in the simplified equivalent three-dimensional simulation model is used as the warpage effect evaluation parameter;

[0066] The parameter group to be optimized is set based on public literature data and existing engineering experience.

[0067] Figure 4A and Figure 4B FIG. 1 is a schematic diagram of a stress distribution cloud diagram and a warpage degree of each structure of a simplified equivalent three-dimensional simulation model in an embodiment of the present invention. Figure 4A and Figure 4B As shown, the stress distribution of the simplified equivalent 3D simulation model can be different in different parts, with the model substrate including Figure 3Taking the ABF-Bottom (the substrate is the bottom plate of ABF (Ajinomoto deposited film)) equivalent layer 1, ABF-Top (the substrate is the top plate of ABF) equivalent layer 2 and Core (the core layer of the substrate) equivalent layer 3 as examples, the warpage of the ABF-Bottom equivalent layer 1, ABF-Top equivalent layer 2 and Core equivalent layer 3 of the substrate in the three-dimensional simulation model are used as warpage effect evaluation parameters, and then the parameter group to be optimized is set according to public literature and existing engineering experience, for example, it may include the thickness of the core layer (Core layer thickness), the heat dissipation cover packaging size (Lid footprint size), the thickness of the heat dissipation cover (Lid thickness), etc. The present invention is not limited to this embodiment, and may also include other parameters.

[0068] Step S3: establishing a DOE test according to the parameter group to be optimized, specifically assigning values ​​to each parameter in the parameter group to be optimized one by one, determining the optimal solution of each parameter according to the numerical change of the warping effect evaluation parameter, and outputting the optimal parameter result, wherein the numerical change of the warping effect evaluation parameter refers to the rate of change of the numerical value;

[0069] In this embodiment, step S3 specifically includes:

[0070] Step S301: using the initial values ​​of each package component in the simplified equivalent three-dimensional simulation model as a reference, recording the change in substrate warpage when the core layer has different thicknesses, so as to obtain the optimal solution of the first parameter;

[0071] Figure 5A and Figure 5B FIG. 1 is a simplified equivalent three-dimensional simulation model in an embodiment of the present invention, showing a substrate warpage variation trend diagram under core layers of different thicknesses. Figure 5A It can be seen that when the thickness of the core layer (the horizontal axis Core layerthickness in the figure) increases from 700um to 1200um, the warpage of the package component at 25℃ (the vertical axis Warpage at25℃ in the figure) changes from 82.1um to 80.0um, and the numerical change rate is 2.56% reduction in warpage; Figure 5B It can be seen that when the thickness of the core layer (the horizontal axis Core layer thickness in the figure) increases from 700um to 1200um, the warpage of the package component at 245℃ (the vertical axis Warpage at 245℃ in the figure) changes from -51.7um to -46.1um, and the numerical change rate is 10.83% reduction in warpage. Figure 4A and Figure 4B It can be seen that increasing the thickness of the core layer can effectively control the warping effect.

[0072] Step S302: using the optimal solution of the first parameter as the initial value, recording the change in substrate warpage when the heat dissipation cover package size (Lid footprint size) is different, so as to obtain the optimal solution of the second parameter;

[0073] Fig. 6A and Figure 6B FIG. 1 is a simplified equivalent three-dimensional simulation model in an embodiment of the present invention, showing a substrate warpage variation trend under heat dissipation cover packages of different sizes. Fig. 6A It can be seen that when the heat dissipation cover package size (the horizontal axis Lidfootprint size in the figure) increases from 2x2 mm to 6x6 mm, the warpage of the package component at 25°C (the vertical axis Warpage at 25°C in the figure) changes from 87.5um to 75.7um, and the numerical change rate is a 13.49% decrease in warpage; Figure 6B It can be seen that when the heat dissipation cover package size (the horizontal axis Lid footprint size in the figure) increases from 2x2 mm to 6x6 mm, the warpage of the package component at 245℃ (the vertical axis Warpage at 245℃ in the figure) changes from -48.7um to -44.5um, and the numerical change rate is 8.62% lower than the warpage. Figure 5A and Figure 5B It can be seen that as the lid footprint size increases, the warpage tends to decrease.

[0074] Step S303: using the second parameter optimal solution as the initial value, recording the change in substrate warpage when the thickness of the heat dissipation cover (Lid thickness) is different, so as to obtain the optimal parameter result.

[0075] Fig. 7A and Figure 7B FIG. 1 is a graph showing a change trend of substrate warpage under heat dissipation covers of different thicknesses in a simplified equivalent three-dimensional simulation model in an embodiment of the present invention. Fig. 7A It can be seen that when the thickness of the heat dissipation cover (the horizontal axis Lidthickness in the figure) increases from 1.7mm to 2.3mm, the warpage of the package component at 25℃ (the vertical axis Warpage at25℃ in the figure) changes from 101.7um to 59.6um, and the numerical change rate is a 41.40% decrease in warpage; Figure 7B It can be seen that when the thickness of the heat dissipation cover (the horizontal axis Lid thickness in the figure) increases from 1.7mm to 2.3mm, the warpage of the package component at 245℃ (the vertical axis Warpage at 245℃ in the figure) changes from -64.6um to -30.9um, and the numerical change rate is 52.17% lower than the warpage. Fig. 6Aand Figure 6B It can be seen that as the thickness of the heat dissipation cover (Lid thickness) increases, the warpage tends to decrease.

[0076] Step S4: preliminarily determine the influence of various influencing factors on the warpage of the package component according to the DOE test results, establish a detailed DOE test based on the numerical change rate of the warpage effect evaluation parameter of different influencing factors and the requirements of the actual production process, and establish an accurate three-dimensional simulation model based on the actual package structure of the device according to the DOE test;

[0077] In this embodiment, the step S4 of establishing an accurate three-dimensional simulation model based on the actual packaging structure of the device includes:

[0078] Create a three-dimensional model corresponding to each structure within the package component;

[0079] Convert the created 3D model into a format that can be recognized by the electronic product warpage analysis simulation environment and import it into the simulation environment to form an accurate 3D simulation model;

[0080] Set material properties for each part of the structure for accurate 3D simulation models.

[0081] by Figure 5A to Figure 7B As an example, the numerical change rate of the warping effect evaluation parameter and the actual production process requirements in step S4 are used to establish a detailed parameter group to be optimized as follows: Figure 5A and Figure 5B It can be seen that when the thickness of the core layer increases from 1000um to 1200um, the change rate of the warpage value is the largest, and the thickness of the core layer meets the requirements of the packaging production process. Therefore, the thickness of the core layer can be set to increase from 1000um to 1200um in a gradient of 20um as the refined parameter group A to be optimized; Fig. 6A and Figure 6B It can be seen that when the heat sink lid package size (Lid footprint size) increases from 2x2 mm to 4x4 mm, the warpage value change rate is the largest, and the heat sink lid package size (Lid footprint size) meets the packaging production process requirements. Therefore, the heat sink lid package size (Lid footprint size) can be set to increase from 2x2 mm to 4x4 mm in a gradient of 0.2 mm as the refined parameter group B to be optimized; Fig. 7A and Figure 7BIt can be seen that when the thickness of the heat dissipation cover (Lidthickness) increases from 1.7mm to 1.9mm, the change rate of the warpage value is the largest, and the thickness of the heat dissipation cover (Lidthickness) meets the requirements of the packaging production process. Therefore, the thickness of the heat dissipation cover (Lid thickness) can be set to increase from 1.7mm to 1.9mm in a gradient of 0.02mm as the refined parameter group C to be optimized.

[0082] Step S5: Set the boundary conditions of the precise three-dimensional simulation model, run the simulation and output the calculation results of the precise three-dimensional simulation model, determine the optimal solution of each parameter again according to the numerical change rate of the warping effect evaluation parameter obtained by the precise three-dimensional simulation model and the actual production process requirements, and output the final optimal parameter results.

[0083] In this embodiment, step S5 specifically includes:

[0084] Step S501: setting boundary conditions of the precise three-dimensional simulation model, wherein the boundary conditions include working environment temperature, analysis steps and time, thermal conditions, fixed point constraints, displacement constraints, etc.; in the actual simulation of this embodiment, the working environment temperature can be set to 150°C, the cooling method can be set to air convection, the lower right corner of the substrate can be set to a fixed point constraint, the point adjacent to the fixed point in the X direction can be set to an X-direction free displacement constraint, and the point in the 45° diagonal direction with the fixed point can be set to an X, Y direction free displacement constraint. In other embodiments, other settings can be made according to requirements, and the present invention is not limited to this;

[0085] Step S502: finely divide the model into grids by region;

[0086] In this embodiment, the common node grid can be divided from bottom to top by dragging the shell unit / solid surface grid, and then other component grids can be divided upward by dragging the solid unit surface. Each layer of component thickness is divided into 3 layers of units; finally, the related nodes are merged by checking the overlapping nodes, and the grid base size is 0.1mm, but not limited to this.

[0087] Step S503: Run the simulation, output the calculation results of the accurate three-dimensional simulation model, and determine the warpage evaluation parameters and the parameter group to be optimized according to the calculation results; wherein the calculation results include: the stress distribution cloud map and the warpage of each structure according to the accurate three-dimensional simulation model; according to the stress distribution, the warpage of the substrate in the accurate three-dimensional simulation model is used as the warpage effect evaluation parameter;

[0088] Step S504: determining the optimal solution of each parameter according to the numerical change rate of the warping effect evaluation parameter and the actual production process requirements, and outputting the final optimal parameter result.

[0089] The DOE test method for packaging component warpage simulation provided by the present invention saves a lot of time spent on early modeling by first establishing a simplified equivalent model, and also solves the problem of repeated modeling caused by early design changes; by using equivalent formulas to calculate the material characteristic parameters of each structure in the simplified equivalent model, the accuracy of the simulation results of the simplified equivalent model is improved; and the present invention is suitable for packaging components of various packaging sizes and structural materials, and can obtain precise simulation results more accurately and quickly, thereby achieving the purpose of early warpage prediction.

[0090] Those skilled in the art can understand that the accompanying drawings are only schematic diagrams of an embodiment, and the modules or processes in the accompanying drawings are not necessarily required to implement the present invention.

[0091] Those skilled in the art can understand that the modules in the device in the embodiment can be distributed in the device in the embodiment according to the description of the embodiment, or can be changed accordingly and located in one or more devices different from the embodiment. The modules in the above embodiment can be combined into one module, or can be further divided into multiple sub-modules.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A DOE test method for packaging component warpage simulation, characterized in that: include: Step S1: establishing a simplified equivalent three-dimensional simulation model based on the actual packaging structure of the device, including: creating a three-dimensional model corresponding to each structure in the packaging component, converting the created three-dimensional model into a format recognizable by the electronic product warpage analysis simulation environment and importing it into the simulation environment to form a three-dimensional simulation model, and finally setting material parameters of each part of the structure of the three-dimensional simulation model; Step S2: Setting the model boundary conditions and running the simulation to establish the parameter group to be optimized, specifically including: Step S201: setting model boundary conditions, wherein the model boundary conditions include working environment temperature, analysis steps and time, thermal conditions, fixed point constraints and / or displacement constraints; Step S202: Divide the model into grids; Step S203: running the simulation, outputting the model calculation results of the simplified equivalent three-dimensional simulation model, and determining the warpage evaluation parameters and the parameter group to be optimized according to the model calculation results; Step S3: Establishing a DOE test according to the parameter group to be optimized, specifically assigning values ​​to each parameter in the parameter group to be optimized one by one, determining the optimal solution of each parameter according to the numerical change of the warping effect evaluation parameter, and outputting the optimal parameter result; Step S4: preliminarily determine the influence of various influencing factors on the warpage of the package component according to the DOE test results, establish a detailed DOE test based on the numerical change rate of the warpage effect evaluation parameter of different influencing factors and the requirements of the actual production process, and establish an accurate three-dimensional simulation model based on the actual package structure of the device according to the DOE test; Step S5: Set the boundary conditions of the precise three-dimensional simulation model, run the simulation and output the calculation results of the precise three-dimensional simulation model, determine the optimal solution of each parameter again according to the numerical change rate of the warping effect evaluation parameter obtained by the precise three-dimensional simulation model and the actual production process requirements, and output the final optimal parameter results.

2. The DOE test method for packaging component warpage simulation according to claim 1, characterized in that: In step S1, the simplified equivalent three-dimensional simulation model is a 1:1 simplified equivalent modeling according to the package component to be simulated, which calculates the material parameters of each part of the structure of the three-dimensional simulation model according to the equivalent formula, wherein the equivalent formula includes: The equivalent formula in the horizontal direction is: equi_parallel =βk1+(1-β)k2; The equivalent formula in the vertical direction is: Where k1 and k2 are the material property parameters of the first material and the second material, respectively, and β is the volume fraction of the first material.

3. The DOE test method for packaging component warpage simulation according to claim 1, characterized in that: The model calculation results in step S203 include: The stress distribution cloud diagram and the warpage of each structure of the simplified equivalent three-dimensional simulation model according to step S1; According to the stress distribution, the warpage of the substrate in the simplified equivalent three-dimensional simulation model is used as the warpage effect evaluation parameter; The parameter group to be optimized is set based on public literature data and existing engineering experience.

4. The DOE test method for packaging component warpage simulation according to claim 1, characterized in that: The numerical change of the warping effect evaluation parameter in step S3 refers to the rate of change of the numerical value.

5. The DOE test method for packaging component warpage simulation according to claim 1, characterized in that: Step S3 specifically includes: Step S301: using the initial values ​​of each packaging component in the simplified equivalent three-dimensional simulation model as a reference, recording the change in substrate warpage when the core layer has different thicknesses, so as to obtain the optimal solution of the first parameter; Step S302: using the optimal solution of the first parameter as the initial value, recording the change in substrate warpage when the package size of the heat dissipation cover is different, thereby obtaining the optimal solution of the second parameter; Step S303: using the optimal solution of the second parameter as the initial value, recording the change in the warpage of the substrate when the thickness of the heat dissipation cover is different, so as to obtain the optimal parameter result.

6. The DOE test method for packaging component warpage simulation according to claim 1, characterized in that: The step S4 of establishing an accurate three-dimensional simulation model based on the actual packaging structure of the device includes: Create a three-dimensional model corresponding to each structure within the package component; Convert the created 3D model into a format that can be recognized by the electronic product warpage analysis simulation environment and import it into the simulation environment to form an accurate 3D simulation model; Set material properties for each part of the structure for accurate 3D simulation models.

7. The DOE test method for packaging component warpage simulation according to claim 1, characterized in that: Step S5 specifically includes: Step S501: setting boundary conditions of the accurate three-dimensional simulation model, wherein the boundary conditions include working environment temperature, analysis steps and time, thermal conditions, fixed point constraints and / or displacement constraints, etc.; Step S502: finely divide the model into grids by region; Step S503: Run the simulation, output the calculation results of the accurate three-dimensional simulation model, and determine the warpage evaluation parameters and the parameter group to be optimized according to the calculation results; wherein the calculation results include: the stress distribution cloud map and the warpage of each structure according to the accurate three-dimensional simulation model; according to the stress distribution, the warpage of the substrate in the accurate three-dimensional simulation model is used as the warpage effect evaluation parameter; Step S504: determining the optimal solution of each parameter according to the numerical change rate of the warping effect evaluation parameter and the actual production process requirements, and outputting the final optimal parameter result.

8. The DOE test method for packaging component warpage simulation according to claim 7, characterized in that: The meshing in steps S202 and S502 is to divide the common node mesh from bottom to top by dragging the shell unit / solid surface mesh, and then to divide other component meshes by dragging the solid unit surface.

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