A method for thermal field simulation analysis and design of a filter, and an apparatus comprising the same.

Abstract

This disclosure provides a finite element method for thermal field simulation of an electronic system. The electronic system includes multiple components. The simulation method includes: establishing a geometric model of the electronic system; identifying multiple heat sources of the electronic system; performing physical field finite element analysis on the multiple heat sources in a single analysis module, and extracting the performance parameters of the multiple heat sources; performing thermal field finite element simulation on the electronic system based on the extracted performance parameters of the multiple heat sources, and obtaining simulation results.

Description

Technical Field

[0001] This disclosure relates to the field of electronics, and more specifically, to the simulation analysis, design methods, and apparatus containing filters. Background Technology

[0002] As a core component of the radio frequency (RF) front-end, filters are crucial for driving the development of next-generation communication standards and the miniaturization and multifunctionality of personal mobile terminals. Therefore, high performance requirements are placed on filters, such as low insertion loss, steep filtering curves, high isolation, and smaller size. Bulk acoustic wave (BAW) resonators are increasingly used in RF filters due to their advantages of small size, high frequency, high power capacity, and high sensitivity. Next-generation BAW technology can effectively solve the aforementioned technical problems of filters. Filters constructed using BAW technology have steeper filtering curves, lower insertion loss, and excellent out-of-band rejection capabilities.

[0003] However, with the increasing application scenarios of filters and the gradual increase in applied power, the self-heating phenomenon of bulk acoustic wave resonators becomes severe. Since filters are highly sensitive to temperature, excessively high temperatures can degrade filter performance. Current design processes do not consider the impact of self-heating, nor do they offer measures to mitigate the performance degradation caused by excessively high filter temperatures due to self-heating. Therefore, a new filter design method that can solve the aforementioned technical problems is what the industry desires. Summary of the Invention

[0004] This disclosure addresses the aforementioned technical problems by proposing a thermal field simulation analysis and design method for filter systems based on the finite element method. This method can effectively analyze the self-heating effect of components in the filter system and optimize the design of the electronic system based on the simulation results.

[0005] A brief overview of this disclosure is given below to provide a basic understanding of certain aspects of it. It should be understood that this overview is not an exhaustive summary of this disclosure. It is not intended to identify key or essential parts of this disclosure, nor is it intended to limit the scope of this disclosure. Its purpose is merely to present some concepts of this disclosure in a simplified form as a prelude to the more detailed description that follows.

[0006] According to a first aspect of this disclosure, a thermal field finite element simulation method for an electronic system is provided. The electronic system includes multiple components. The simulation method includes: establishing a geometric model of the electronic system; identifying multiple heat sources of the electronic system; performing physical field finite element analysis on the multiple heat sources in a single analysis module, and simultaneously extracting performance parameters of the multiple heat sources; performing thermal field finite element simulation on the electronic system based on the extracted performance parameters of the multiple heat sources, and obtaining simulation results.

[0007] According to a second aspect of this disclosure, a structural design method for an electronic system is provided. The electronic system includes multiple components. The design method includes: determining the physical structure of the components; determining the physical structure of the electronic system; simulating the physical structure of the components and the electronic system using the aforementioned thermal field finite element simulation method to obtain simulation results; and optimizing the structure of the components or the electronic system based on the simulation results.

[0008] According to a third aspect of this disclosure, a computer-readable storage medium is provided for storing computer instructions for performing the method as described in any of the preceding claims.

[0009] According to a fourth aspect of this disclosure, a heat assessment apparatus for an electronic system is provided, comprising a storage medium and a processing unit, wherein the storage medium is configured to store computer instructions that can execute the method described in any of the foregoing descriptions, and the processing unit is configured to invoke the computer instructions.

[0010] According to a fifth aspect of this disclosure, an apparatus for designing an electronic system is provided, including a storage medium and a processing unit, the storage medium being used to store computer instructions that can execute the methods described above, and the processing unit being able to invoke the computer instructions.

[0011] The scheme disclosed herein can help achieve at least one of the following effects: shorten simulation time, improve simulation efficiency, obtain simulation results of steady-state thermal distribution of the filter under different power, perform reasonable optimization design for components with more severe heat generation, improve the self-heating effect of components, reduce the temperature of the filter, and improve the working stability of the filter. Attached Figure Description

[0012] The specific details of this disclosure are described below with reference to the accompanying drawings, which will facilitate a more readily understanding of the above and other objects, features, and advantages of this disclosure. The drawings are merely for illustrating the principles of this disclosure. The dimensions and relative positions of the elements are not necessarily drawn to scale in the drawings.

[0013] Figure 1 A flowchart illustrating the filter structure design according to a specific embodiment of this disclosure is shown.

[0014] Figure 2 A flowchart of the finite element thermal field simulation of the filter according to this disclosure is shown.

[0015] Figure 3 The filter S-parameter curves obtained from the simulation of this disclosure are shown.

[0016] Figures 4-6 The simulation results of the thermal field at different frequencies are shown when the power of the filter disclosed in this paper is 1W.

[0017] Figures 7-9 The simulation results of the thermal field at different frequencies are shown when the power of the filter disclosed in this paper is 3W. Detailed Implementation

[0018] Exemplary disclosures of this disclosure will be described below with reference to the accompanying drawings. For clarity and brevity, not all features implementing this disclosure are described in the specification. However, it should be understood that many disclosure-specific decisions can be made in developing any such implementation of this disclosure to achieve the developer’s specific goals, and these decisions may vary depending on the specific disclosure.

[0019] It should also be noted that, in order to avoid obscuring this disclosure with unnecessary details, only features closely related to the scheme according to this disclosure are shown in the accompanying drawings, while other details that are not closely related to this disclosure are omitted.

[0020] It should be understood that this disclosure is not limited to the described embodiments by virtue of the following description with reference to the accompanying drawings. Throughout this document, features may be substituted or borrowed between different embodiments where feasible, and one or more features may be omitted in one embodiment. It should be understood that the design methods of this disclosure are exemplary in the embodiments.

[0021] This disclosure can be applied to electronic systems with multiple components. Electronic systems with multiple components typically have their components interconnected and integrated into a single package using interconnect technology. As the number of components increases, the complexity of the electronic system also increases, and the heat generated during operation will significantly affect the performance of the electronic system.

[0022] Existing technologies include finite element thermal field simulation analysis of electronic systems using a single physical field; however, this results in insufficient accuracy. Hybrid thermal field simulation analysis also exists, which primarily employs circuit simulation analysis supplemented by finite element simulation analysis, combining the two for a comprehensive thermal field simulation. However, the results of this comprehensive thermal field simulation analysis do not accurately reflect the actual heating phenomena of the devices. In previous inventions, the applicant proposed finite element thermal field simulation analysis of electronic systems to identify multiple heat sources during system operation. By selecting specific heat sources, finite element analysis (FEA) is used to perform physical field analysis on each heat source in different analysis modules, followed by coupled field analysis, to obtain simulation results that more closely resemble the actual heating phenomena of the devices. However, this method requires selecting different analysis modules within the finite element analysis software for each heat source, performing physical field analysis separately, and then coupling the results. This results in a lengthy simulation process and low efficiency.

[0023] This disclosure provides a novel finite element method for thermal field simulation of electronic systems, which can obtain simulation results that more closely match the actual heating phenomena of devices, and effectively reduce the time of thermal field finite element simulation analysis, thereby improving the efficiency of thermal field finite element simulation.

[0024] The finite element analysis (FEM) method mentioned in this disclosure is a numerical method for solving partial differential equations. FEM uses a simpler problem to replace a complex one, and then simulates and solves the real physical system through mathematical approximation. Specifically, FEM considers the solution domain as composed of many small interconnected subdomains called finite elements. For each element, a suitable (simpler) approximate solution is assumed, and then the overall satisfying conditions are derived to obtain an approximate solution to the problem. FEM not only boasts high computational accuracy and adaptability to various complex shapes, but it can also transform the solution results of partial differential equations into readable post-processing results such as digital images and animations, making the analysis results intuitive and visual, thus effectively meeting the analysis needs of engineering. This disclosure uses finite element analysis software developed based on finite element analysis to perform finite element thermal field simulation analysis of an electronic system.

[0025] The finite element analysis software mentioned in this disclosure refers to various finite element analysis software such as Comsol, Ansys, and Abaqus, which have undergone decades of development and improvement and help transform finite element analysis into social productivity. For ease of explanation, this disclosure uses Comsol software as an example to perform finite element thermal field simulation analysis of a filter. However, those skilled in the art should understand that the finite element thermal field simulation analysis scheme of this disclosure can be applied to various finite element analysis software.

[0026] Please see Figure 1 , Figure 1 A flowchart illustrating the structural design of an electronic system according to a specific embodiment of this disclosure is shown.

[0027] like Figure 1 As shown, the filter structure optimization design method disclosed herein may include the following steps: S11: Determine the physical model of the component; S12: Determine the physical model of the electronic system; S13: Perform simulation based on finite element thermal field simulation analysis; S14: Optimize the physical model of the component or electronic system based on the simulation results; The above steps may be repeated iteratively multiple times.

[0028] Please see Figure 2 , Figure 2 A flowchart of finite element thermal field simulation analysis of an electronic system according to a specific embodiment of this disclosure is shown.

[0029] like Figure 2 As shown, the finite element thermal field simulation analysis of the electronic system disclosed herein may include the following steps: S131: Establish the geometric model of the electronic system; S132: Determine multiple heat sources of the electronic system, perform physical field finite element simulation analysis on multiple heat sources in a single analysis module, and extract the required performance parameters of multiple heat sources; S133: Perform thermal field finite element simulation on the electronic system based on the extracted performance parameters of multiple heat sources; S134: Obtain the temperature distribution under steady state.

[0030] Furthermore, the steady-state temperature distribution obtained through finite element thermal field simulation analysis can be used for the optimized design of electronic system structures from multiple perspectives.

[0031] In summary, the design method and simulation analysis of the electronic system disclosed herein have the following advantages:

[0032] 1) This disclosure, through the effective determination of heat sources in electronic systems, selects the corresponding analysis module in the appropriate finite element analysis software as the physical field interface, and extracts the corresponding performance parameters of different heat sources simultaneously in the same analysis module based on the determined multiple different heat sources.

[0033] 2) The thermal field simulation results disclosed herein can approximate the heating conditions of real electronic systems as closely as possible.

[0034] 3) The simulation-based design method disclosed herein effectively shortens the design cycle, reduces design costs, and can effectively improve the performance of electronic systems without tape-out verification.

[0035] To better understand the inventive concept of this disclosure, a filter is used as a specific embodiment of an electronic system to illustrate the inventive concept. However, it should be understood that the concept of this disclosure is applicable to any electronic system with multiple components and is not limited to filters.

[0036] A filter comprises multiple components, such as bulk acoustic wave (BAW) resonators, which are interconnected and integrated into the filter. The heat dissipation of each BAW resonator varies depending on its specific placement on the filter's substrate. Furthermore, the specific material selection, structural configuration, and conductive path arrangement of the electrical connections for each BAW resonator within the filter present challenges in simulating and analyzing the filter's thermal field.

[0037] Specifically, the piezoelectric layer in a bulk acoustic wave resonator is used to convert sound waves into electrical signals. The vast majority of the acoustic energy is contained within the piezoelectric layer, resulting in high heat loss due to piezoelectric losses. Secondly, the ohmic losses of the electrodes in the bulk acoustic wave resonator are another mechanism contributing to heat loss.

[0038] Existing technologies employ comprehensive simulation analysis to analyze the heat generation of filters. This comprehensive simulation analysis includes circuit simulation analysis and finite element analysis (FEM). Circuit simulation analysis performs equivalent circuit simulation of the filter to calculate the power dissipation of the bulk acoustic wave resonators due to the applied signal. Finite element analysis obtains the thermal resistance matrix of all resonators in the filter through finite element analysis, and then correlates the power dissipation with the thermal resistance matrix for comprehensive simulation. However, the simulation results do not accurately reflect the actual heat generation phenomena of the devices.

[0039] In the finite element thermal field simulation analysis and filter design method of this disclosure, finite element analysis is used to perform physical field analysis on the piezoelectric layer and upper and lower electrodes of the bulk acoustic resonator in the filter in the piezoelectric module, and then coupling field analysis is performed in the solid heat transfer module. Through the specific design of the finite element thermal field simulation analysis, the simulation analysis of this disclosure is more consistent with the actual heating phenomenon of the device, while effectively shortening the simulation time, thus providing strong support for the structural optimization design of the filter.

[0040] Determine the physical model of the components

[0041] A bulk acoustic wave resonator can be an air-cavity thin-film bulk acoustic wave resonator, a Bragg-reflection type thin-film bulk acoustic wave resonator, or a reverse-etched type thin-film bulk acoustic wave resonator. These three types of thin-film bulk resonators are collectively referred to as bulk acoustic wave resonators. This disclosure uses an air-cavity thin-film bulk acoustic wave resonator as an example to illustrate the design of a physical model of the bulk acoustic wave resonator and to determine its specific structure, materials, and performance parameters.

[0042] The physical model of a bulk acoustic wave resonator includes at least a substrate, a cavity formed in the substrate, a lower electrode, an upper electrode, and a piezoelectric layer sandwiched between the upper and lower electrodes. The upper and lower electrodes and the piezoelectric layer form a stacked structure, and the overlapping region between the upper electrode, the piezoelectric layer, and the lower electrode is the active region of the bulk acoustic wave resonator. Specifically, the piezoelectric layer is made of a piezoelectric material with electromechanical conversion capabilities, such as aluminum nitride, doped aluminum nitride, or zirconate titanate, and is used to achieve the conversion between acoustic waves and electrical signals. Exemplary performance parameters of the bulk acoustic wave resonator include the length, thickness, area, and material of each layer of the resonator.

[0043] Although this disclosure uses the most basic stacked structure with a bulk acoustic resonator as an example, it does not imply a limitation on stacked structures that include other additional functional layers. Other additional functional layers may exemplify additional functional layers such as mass load layers, frames, etc.

[0044] Determine the physical model of the filter

[0045] Based on the determined structure, materials, and performance parameters of the bulk acoustic wave filter, a physical model of the filter containing the bulk acoustic wave resonator is determined. This physical model includes the filter's topology, order, and the layout of each component in the filter on the substrate.

[0046] The filter performance was simulated to obtain the piezoelectric loss density and electrode loss density distribution.

[0047] Because the heat dissipation caused by piezoelectric loss is relatively high, it has been selected as one of the main heat sources of the filter. Therefore, in the finite element thermal field simulation analysis disclosed herein, Comsol's piezoelectric module is selected as the physical field interface, in order to obtain the loss density of the piezoelectric material and the electrode loss density at the same time through the physical field finite element simulation in the piezoelectric module.

[0048] After determining the module type to be analyzed in the finite element analysis software, the first step is to build the geometric model of the filter, including the bulk acoustic resonator, based on the physical model of the filter. The geometric model of the filter should be based on the dimensions required in the design. Specifically, the geometric model can be drawn directly in the Comsol environment, or the designed 3D geometric model of the filter can be imported into the Comsol software. Then, the material parameters and initial conditions of each component of the filter are input. In the piezoelectric module, when performing physical field simulation of the filter, it is necessary to assign values ​​to the relative permittivity of the upper and lower electrodes. Since the expression for the relative permittivity in complex form is ε... r

[0049] (ω)=ε r ′(ω)-jε r ″(ω), where the imaginary part ε r ″(ω) represents ohmic loss; it is caused by the polarization process failing to keep up with changes in the external field. Since the piezoelectric module defaults to treating the electrodes of the bulk acoustic wave resonator in the filter as equipotential bodies, meaning the electrodes are considered to have no ohmic loss, the piezoelectric module defaults to setting the imaginary part of the relative permittivity of the electrodes to zero when setting the relative permittivity. For bulk acoustic wave resonators, as application scenarios expand and increase, the applied frequencies will also differ; therefore, it is impossible for the resonator electrodes to be without ohmic loss in practical applications. To simulate and analyze the heating phenomena of actual devices more accurately, the applicant, in a previous invention, first performed separate performance simulations of the piezoelectric layer of the bulk acoustic wave resonator in the piezoelectric module, and then used the current module as the physical field interface for the upper and lower electrodes of the bulk acoustic wave resonator. The corresponding ohmic loss density distribution of the upper and lower electrodes was obtained through simulation in the current module, and then the coupling field was simulated. However, this simulation method is time-consuming and inefficient.

[0050] The applicant considers that finite element analysis is a numerical method for solving partial differential equations. The Comsol software, developed based on finite element analysis, contains the Comsol partial differential equation system, which is a mathematical model that uses a simpler problem to replace a complex one, simulating and solving a real physical system through mathematical approximation. This model can be used to simulate the behavior of physical systems, thus helping to better understand their operating mechanisms. In this disclosure, by utilizing partial differential equations in the Comsol current module that can simulate the behavior of a filter under static current mode, an adaptive equivalent treatment is applied to the partial differential equations to obtain a more realistic electrode relative permittivity ε with ohmic losses. r (ω).

[0051] Specifically, the partial differential equations describing the physical field of current in the Comsol current module are expressed as follows:

[0052]

[0053] in, Here, σ is the Hamiltonian operator, ε0 is the conductivity, and ε is the absolute permittivity. r ω is the relative permittivity, ω is the angular frequency, and V is the voltage.

[0054] Dividing both sides of equation one by jω yields:

[0055]

[0056] The partial differential equations describing electrostatic physical fields in COMSOL are expressed as follows:

[0057]

[0058] in ε is the Hamiltonian operator, ε0 is the absolute permittivity, and ε r is the relative permittivity, and V is the voltage.

[0059] By comparing Equation 2 with Equation 3, the relative permittivity of the upper and lower electrodes with ohmic loss can be obtained.

[0060] In the finite element thermal field simulation analysis of this disclosure, the electrode ohmic loss is substituted as an imaginary part into the electrode relative permittivity of the piezoelectric module. Then, adaptive model processing is performed within the piezoelectric module. For example, in the finite element thermal field simulation analysis of this disclosure, based on the significant difference between the substrate thickness and filter thickness in the actual product, sound waves propagate along the substrate thickness direction with little or no reflection. Therefore, when constructing the actual filter geometric model, the construction of the substrate geometric model is partially omitted. Based on the fact that sound waves reflect at the boundaries, low-reflection boundary conditions or a perfectly matched layer are added below the substrate to simulate the propagation of sound waves in the substrate, thereby achieving minimal or no reflection of sound waves. This model processing avoids interference from irrelevant factors while improving computational efficiency during simulation.

[0061] After properly processing the filter's geometric model, based on the principles of finite element analysis, it is necessary to mesh the filter's geometric model. When meshing the filter's geometric model, the frequency range of the filter and the structural dimensions of the resonator should be comprehensively considered to achieve a balance between computational accuracy and efficiency.

[0062] Then, physical field simulation of the filter is performed in the piezoelectric module. After the software calculation is completed, the scattering parameters (S-parameters) of the filter can be obtained. According to the piezoelectric loss operator provided by Comsol software, the loss density distribution of the upper and lower electrodes and piezoelectric materials at different frequencies can be obtained.

[0063] For details, please refer to Figure 3, Figure 3 A schematic diagram of the scattering parameters is shown. S11 is the input reflection coefficient, which is the input return loss, and S21 is the output reflection coefficient, which is the output return loss. The parameters S11 and S21 facilitate subsequent thermal field simulation analysis.

[0064] Finite element thermal field simulation analysis was performed on the resonator.

[0065] Since there are two heat sources in the resonator, it is known that there are multiple physical fields in the resonator. After obtaining the piezoelectric loss density distribution of the piezoelectric layer and the corresponding ohmic loss density distribution of the upper and lower electrodes, the solid heat transfer module in Comsol is selected to perform coupled field analysis to visualize the heating of the resonator.

[0066] After determining the module type to be analyzed in the finite element software, a heat transfer physical field is added based on the aforementioned simulation. Using the withsol operator built into Comsol, the piezoelectric loss density and ohmic loss density are introduced into the solid heat transfer module as heat sources. The withsol operator is used to access arbitrary solutions in the constructed geometric model.

[0067] Furthermore, natural convection is set on the upper surface of the filter, and the bottom surface temperature of the substrate is set to room temperature, for example, 25°C, to simulate the normal working environment of the filter. The results of different physical fields are coupled, and the coupling results of the multi-physical fields are solved and analyzed to obtain the temperature distribution of the filter, thereby approximating the self-heating effect of the real resonator as much as possible.

[0068] In one embodiment, the above-described scheme was tested, and the results were obtained. Figures 4-9 The diagram shown. Figures 4-6 The simulation results of the thermal field at different frequencies are shown when the power of the filter in this disclosure is 1W. Figures 7-9 The following diagram shows the thermal field simulation results at different frequencies when the power of the filter in this disclosure is 3W. (For ease of display,...) Figures 4-9 The electrode connections between the bulk acoustic wave resonators are hidden within. Specifically, Figure 4 The image shows the thermal field simulation results for a filter with a power of 1W and a frequency of 2.29GHz. Figure 5 The image shows the thermal field simulation results for a filter with a power of 1W and a frequency of 2.37GHz. Figure 6 The image shows the thermal simulation results of a filter with a power of 1W and a frequency of 2.41GHz. Figure 7 The image shows the thermal field simulation results for a filter with a power of 3W and a frequency of 2.29GHz. Figure 8 The image shows the thermal field simulation results for a filter with a power of 3W and a frequency of 2.37GHz. Figure 9 The image shows the thermal simulation results of a filter with a power of 3W and a frequency of 2.41GHz.

[0069] Depend on Figures 4-6 , Figures 7-9 It is clear that, when the power is the same but the frequency is different, different bulk acoustic resonators in the filter have different heating temperatures. (Comparison) Figure 4 and Figure 7 , Figure 5 and Figure 8 , Figure 6 and Figure 9 It can be clearly seen that when the frequency is the same but the power is different, the heating temperature of the same bulk acoustic wave resonator in the filter increases with the increase of power. That is, the higher the power, the more serious the self-heating effect of the same bulk acoustic wave resonator.

[0070] The test results are largely consistent with those of the applicant's previous invention, which involved first performing a separate physical field simulation of the piezoelectric layer of the bulk acoustic wave resonator in the piezoelectric module, then using the current module as the physical field interface for the upper and lower electrodes of the bulk acoustic wave resonator. The ohmic loss density distribution of the upper and lower electrodes was obtained through physical field simulation in the current module, and then the coupling field was simulated in the solid heat transfer module. However, the simulation computation time was reduced by approximately one-third compared to the previous method. This demonstrates that the simulation method disclosed herein effectively shortens the simulation time and improves simulation efficiency while closely approximating the heating conditions of a real electronic system.

[0071] The structure of the filter is optimized.

[0072] Based on the above thermal simulation method, different powers are applied to the filter during simulation to obtain thermal simulation results. Then, based on the highest temperature of each bulk acoustic wave resonator in the thermal simulation results, it can be determined whether the highest temperature exceeds the normal operating temperature threshold of the bulk acoustic wave resonator, and thus obtain the maximum power that each bulk acoustic wave resonator can withstand without damaging the bulk acoustic wave resonator.

[0073] Furthermore, based on the maximum power that each bulk acoustic wave resonator can withstand, the filter is redesigned. Based on the redesigned filter, finite element thermal field simulation analysis of the filter is performed again to obtain the maximum power that each bulk acoustic wave resonator in the redesigned filter can withstand, until this maximum power meets the requirements for normal operation of the bulk acoustic wave resonators.

[0074] For example, redesigning the filter could involve splitting a bulk acoustic wave resonator whose highest temperature in the finite element thermal field simulation analysis exceeds the normal operating temperature threshold. Specifically, a single bulk acoustic wave resonator can be split into at least two larger-area resonators; these split resonators can then be connected in series or parallel to reduce the self-heating effect of the bulk acoustic wave resonators. It is understood that the number of split bulk acoustic wave resonators should be adapted to the predetermined layout area of ​​the filter.

[0075] For example, redesigning the filter can also add a heat dissipation mechanism at the bulk acoustic wave resonator where the highest temperature exceeds the normal operating temperature threshold in finite element thermal field simulation analysis. Specifically, metal vias can be added to the bulk acoustic wave resonator where the self-heating effect is severe. The metal vias can be set on the substrate at the position corresponding to the bulk acoustic wave resonator, utilizing the excellent thermal conductivity of metal to better conduct heat away.

[0076] This implementation provides a feasible solution for thermal field simulation of filters. Based on the visualization results of the simulation, it provides strong support for optimizing the filter design, shortens the design cycle, reduces the design cost, and effectively improves the filter performance without the need for tape-out verification.

[0077] The present disclosure has been described above with reference to specific implementation schemes through simulation analysis and design methods. However, those skilled in the art should understand that these descriptions are exemplary and are not intended to limit the scope of protection of the present disclosure.

[0078] Understandably, the implementation schemes in this disclosure can be implemented in the form of computer instructions.

[0079] Understandably, the embodiments in this disclosure can be stored on a computer-readable storage medium (including but not limited to disk storage, read-only optical disk, optical storage, etc.) via computer program instructions.

[0080] Understandably, the embodiments in this disclosure can produce an electronic system heat assessment device or an electronic system design device by providing computer program instructions to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device.

[0081] Those skilled in the art can make various modifications and alterations to this disclosure in accordance with the spirit and principles of this disclosure, and such modifications and alterations are also within the scope of this disclosure.

Claims

1. A finite element method for simulating the thermal field of an electronic system, the electronic system comprising multiple components, characterized in that, include: Determine the physical model of the electronic system; Multiple heat sources of the electronic system are identified. An appropriate analysis module is selected based on the heat loss of the multiple heat sources. A geometric model of the electronic system is established in a single analysis module according to the physical model. Material parameters and initial conditions of each component are input into the geometric model. The heat loss of other heat sources is compensated to the analysis module in the form of parameters. Based on the geometric model, physical field finite element analysis is performed on the multiple heat sources of the electronic system, and the performance parameters of the multiple heat sources are extracted. The electronic system was subjected to thermal field finite element simulation based on the performance parameters of multiple heat sources extracted, and the simulation results were obtained.

2. The thermal field finite element simulation method as described in claim 1, characterized in that: The electronic system is a filter, the component includes a bulk acoustic wave resonator, the bulk acoustic wave resonator includes a piezoelectric layer and upper and lower electrodes, and the plurality of heat sources include a piezoelectric layer and upper and lower electrodes.

3. The thermal field finite element simulation method as described in claim 2, characterized in that: The acoustic analysis module is selected as the physical field analysis module of the filter, and the equivalent electrical parameters are compensated into the acoustic analysis module so that the physical field analysis of the multiple heat sources can be performed in the same analysis module.

4. The thermal field finite element simulation method as described in claim 3, characterized in that: The acoustic analysis module is a piezoelectric module, and the equivalent electrical parameters are the equivalent relative permittivity of the upper and lower electrodes with ohmic loss.

5. The thermal field finite element simulation method as described in claim 4, characterized in that: The relative permittivity equivalence is obtained by comparing the electrostatic partial differential equation in the finite element simulation software with the processed current partial differential equation.

6. The thermal field finite element simulation method as described in claim 5, characterized in that: The partial differential equation for the current is: ,in For Hamiltonian operators, For conductivity, For absolute permittivity, For relative permittivity, Angular frequency, Let j be the voltage; divide both sides by j. The processed current partial differential equation is obtained. .

7. The thermal field finite element simulation method as described in claim 6, characterized in that: The electrostatic partial differential equation is as follows: ,in For Hamiltonian operators, For absolute permittivity, For relative permittivity, The voltage is used; by comparing the electrostatic partial differential equation with the processed current partial differential equation, the relative permittivity of the upper and lower electrodes with ohmic losses is obtained. .

8. The thermal field finite element simulation method as described in claim 7, characterized in that: Replace the imaginary part of the relative permittivity of the upper and lower electrodes in the piezoelectric module with the imaginary part of the relative permittivity of the upper and lower electrodes with ohmic loss.

9. The finite element simulation method for thermal field as described in claim 8, characterized in that: Model processing and mesh generation are performed in the piezoelectric module.

10. The finite element simulation method for thermal field as described in claim 9, characterized in that: The scattering parameters of the filter are obtained by performing physical field simulation in the piezoelectric module, and then the ohmic loss density distribution of the upper and lower electrodes and the piezoelectric loss density distribution of the piezoelectric material are obtained.

11. The finite element simulation method for thermal field as described in claim 10, characterized in that, Based on the extracted piezoelectric loss density distribution and ohmic loss density distribution, a steady-state thermal field finite element simulation of the filter was performed in the solid heat transfer module to obtain the simulation results of the temperature distribution under steady state.

12. A structural design method for an electronic system, the electronic system comprising multiple components, characterized in that, include: Determine the physical structure of the component; Determine the physical structure of the electronic system; The thermal field finite element simulation method according to any one of claims 1-11 is used to simulate the physical structure of the component and the electronic system to obtain simulation results; Based on the simulation results, the structure of the component or electronic system is optimized.

13. The design method as described in claim 12, characterized in that: The simulation results include sub-simulation results corresponding to each component, and structural optimization of the component or electronic system structure based on the simulation results includes: Determine whether the sub-simulation result corresponding to the component exceeds the threshold; If so, the component is split to obtain at least two sub-components.

14. The design method as described in claim 12, characterized in that: The simulation results include sub-simulation results corresponding to each component, and the structural optimization of the component or electronic system structure based on the simulation results includes: Determine whether the sub-simulation result corresponding to the component exceeds the threshold; If so, a heat dissipation channel shall be added at the location of the component.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store computer instructions for performing the method as described in any one of claims 1-14.

16. A heat assessment device for an electronic system, characterized in that: The device includes a storage medium and a processing unit, wherein the storage medium is used to store computer instructions that can execute the method as described in any one of claims 1-11, and the processing unit can invoke the computer instructions.

17. A design apparatus for an electronic system, characterized in that: The device includes a storage medium and a processing unit, wherein the storage medium stores computer instructions that can execute the method as described in any one of claims 12-14, and the processing unit can invoke the computer instructions.

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