Flexible electronic device bending performance characterization analysis method

Abstract

The invention provides a flexible electronic device bending performance characterization analysis method. The method comprises the following steps: establishing a flexible electronic bending process finite element simulation model based on acquired information of a flexible electronic device; based on a finite element simulation model, laminated structure deformation and stress distribution evolution information in the flexible electronic bending process is obtained, and the position of a region where stress concentration occurs and the stress magnitude are obtained; obtaining evolution information of crystal grains in the bending process of the flexible electronic device; and analyzing the bending performance of the flexible electronic device based on the laminated structure deformation and stress distribution evolution information, the position of the region where stress concentration occurs, the stress size and the evolution information of the crystal grains in the bending process. And the purpose of clearly knowing internal factors influencing the bending performance of the flexible electronics is achieved.

Description

Technical Field

[0001] The present invention belongs to the field of flexible electronic technology, and in particular relates to a method for characterizing and analyzing the bending performance of a flexible electronic device. Background Art

[0002] As an "advanced version" of traditional electronics, flexible electronics is developing into a national pillar industry with a huge scale and a long-term high-speed growth trend. Due to its bendable, foldable, stretchable and twistable characteristics, it is widely used in consumer electronics, medical health and aerospace fields. At present, the most required performance in flexible electronic application scenarios is bending performance, but the characterization of bending performance and the analysis of the corresponding core mechanism are missing, and the internal factors affecting the bending performance of flexible electronics are unknown, which reduces the optimization and upgrading speed of corresponding products. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention provides a method for characterizing and analyzing the bending performance of flexible electronic devices, which at least partially solves the problem of unclear intrinsic factors affecting the bending performance of flexible electronics in the prior art.

[0004] In a first aspect, an embodiment of the present disclosure provides a method for characterizing and analyzing the bending performance of a flexible electronic device, comprising: A finite element simulation model of the flexible electronic bending process is established based on the acquired information of the flexible electronic device; Based on the finite element simulation model, the deformation and stress distribution evolution information of the laminated structure during the bending process of flexible electronics is obtained, and the location and magnitude of the stress concentration area are obtained; Obtaining information on the evolution of grains during the bending process of flexible electronic devices; The bending performance of flexible electronic devices is analyzed based on the deformation and stress distribution evolution information of the laminated structure, the location of the stress concentration area, and the stress magnitude and grain evolution information during the bending process.

[0005] Optionally, the acquired information of the flexible electronic device includes: The stacking structure information of flexible electronic devices and the property information of structural materials in the stacking structure.

[0006] Optionally, the stacked structure includes an insulating film layer, a conductive film layer and an adhesive layer.

[0007] Optionally, the acquired information of the flexible electronic device further includes: Bending inner corner radius and bending frequency of flexible electronic devices under service conditions.

[0008] Optionally, obtaining the evolution information of the grains during the bending process of the flexible electronic device includes: obtaining the evolution information of the grains of the sample during the bending process based on a bending test of the flexible electronic sample.

[0009] Optionally, obtaining the evolution information of the grains of the sample during the bending process based on the flexible electronic sample bending test includes: The data of electron backscatter diffraction test on the conductive film layer of the flexible electronic sample before, during and after bending and breaking are obtained by scanning electron microscope.

[0010] Optionally, the obtaining of evolution information of grains of the sample during a bending process based on a flexible electronic sample bending test includes: obtaining evolution information of grains of a conductive film layer of the sample during the bending process.

[0011] Optionally, the evolution information of the conductive film layer grains during the bending process includes: Information on changes in grains, grain boundaries, Schmidt factors and local misorientation in planes and cross sections.

[0012] Optionally, analyzing the bending performance of the flexible electronic device includes: The excellent bending performance of flexible electronic devices is manifested in relatively small stress values, and the stress concentration areas are mostly located in the middle area of ​​each stacked layer rather than at the junction of each layer; The excellent bending performance of flexible electronics is manifested in the high volume content of equiaxed crystals, unclear texture, and light strain accumulation during deformation.

[0013] Optionally, after the step of analyzing the bending performance of the flexible electronic device, the method further includes: Based on the analysis results, the production process of flexible electronic devices, as well as the laminated structure and materials of flexible electronic devices are adjusted.

[0014] The method for characterizing and analyzing the bending performance of flexible electronic devices provided by the present invention obtains the deformation of the laminated structure and the stress distribution evolution information during the bending process of flexible electronics through a finite element simulation model, obtains the regional location and stress magnitude of stress concentration, and evaluates the bending resistance of flexible electronics from multiple scales by obtaining the evolution information of grains during the bending process. The core mechanism thereof is analyzed, providing multi-dimensional technical support for product optimization and upgrading, thereby achieving the purpose of clearly understanding the intrinsic factors affecting the bending performance of flexible electronics. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0016] Figure 1 A flow chart of a method for characterizing and analyzing the bending performance of a flexible electronic device provided in an embodiment of the present disclosure; Figure 2A schematic diagram of a flexible electronic stacked structure provided in an embodiment of the present disclosure; Figure 3 A schematic diagram of the flexible electronic bending provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0017] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0018] It should be clear that the following embodiments of the present disclosure are described by specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other in the absence of conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0019] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0020] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The illustrations only show components related to the present disclosure rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0021] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0022] This embodiment discloses a method for characterizing and analyzing the bending performance of a flexible electronic device, including: A finite element simulation model of the flexible electronic bending process is established based on the acquired information of the flexible electronic device; Optionally, the acquired information of the flexible electronic device includes: The stacking structure information of flexible electronic devices and the material property information in the stacking structure.

[0023] A laminated structure is a structure that achieves complex circuit functions by stacking multiple functional layers together during the design and manufacturing process. This laminated structure is usually composed of alternating conductive layers and insulating layers to meet different electrical performance and functional requirements.

[0024] Optionally, the stacked structure includes an insulating film layer, a conductive film layer and an adhesive layer.

[0025] Optionally, the acquired information of the flexible electronic device further includes: Bending inner corner radius and bending frequency of flexible electronic devices under service conditions.

[0026] Based on the finite element simulation model, the deformation and stress distribution evolution information of the laminated structure during the bending process of flexible electronics is obtained, and the location and magnitude of the stress concentration area are obtained; Obtaining information on the evolution of grains during the bending process of flexible electronic devices; The bending performance of flexible electronic devices is analyzed based on the deformation and stress distribution evolution information of the laminated structure, the location of the stress concentration area, and the stress magnitude and grain evolution information during the bending process.

[0027] Optionally, obtaining the evolution information of the grains during the bending process of the flexible electronic device includes: obtaining the evolution information of the grains of the sample during the bending process based on a bending test of the flexible electronic sample.

[0028] Optionally, obtaining the evolution information of the grains of the sample during the bending process based on the flexible electronic sample bending test includes: Obtain data from electron backscatter diffraction tests of flexible electronic samples before, during, and after bending and breaking using a scanning electron microscope.

[0029] Optionally, the obtaining of evolution information of grains of the sample during a bending process based on a flexible electronic sample bending test includes: obtaining evolution information of grains of a conductive film layer of the sample during the bending process.

[0030] Optionally, the evolution information of the conductive film layer grains during the bending process includes: Information on changes in grains, grain boundaries, Schmidt factors and local misorientation in planes and cross sections.

[0031] Optionally, analyzing the bending performance of the flexible electronic device includes: The excellent bending performance of flexible electronic devices is manifested in relatively small stress values, and the stress concentration areas are mostly located in the middle area of ​​each stacked layer rather than at the junction of each layer; The excellent bending performance of flexible electronics is manifested in the high volume content of equiaxed crystals, unclear texture, and light strain accumulation during deformation.

[0032] Optionally, after the step of analyzing the bending performance of the flexible electronic device, the method further includes: Based on the analysis results, the production process of flexible electronic devices, as well as the laminated structure and materials of flexible electronic devices are adjusted.

[0033] In a specific implementation scenario, such as Figure 1 As shown in the figure, the flexible electronic bending performance characterization and mechanism analysis methods include macroscopic and microscopic levels, corresponding to finite element simulation and scanning electron microscope crystallographic analysis, specifically: Obtaining the laminated structure information of flexible electronics and the corresponding structural material property information of the laminated structure; Figure 2 As shown, the laminated structure generally includes an insulating film layer, a conductive film layer and an adhesive layer, that is, material property information corresponding to the insulating film layer, material property information corresponding to the conductive film layer and material property information corresponding to the adhesive layer.

[0034] like Figure 3 As shown, the bending inner angle radius, bending frequency, etc. under the service conditions of flexible electronics are obtained; Establish a finite element simulation model of the corresponding flexible electronic bending process according to the information; Calculating the finite element model to obtain the deformation and stress distribution evolution information of the laminated structure of the flexible electronics from the start to the final end of the bending deformation, and obtaining the location of the stress concentration region and the stress magnitude; The excellent bending performance of flexible electronics is manifested in relatively small stress values, with stress concentration areas mostly located in the middle of each stack rather than at the junction of each layer; Take a certain number of flexible electronic samples for bending test, and then take samples before bending, during bending (1 / 2 life) and after bending and breaking (2 / 2 life) for electron backscatter diffraction (EBSD) test on scanning electron microscope (SEM); Mount the sample on the SEM sample stage and ensure that the sample surface is smooth and free of contamination and extra deformation. Set up the EBSD analysis program in the SEM, select the appropriate voltage and current, and adjust the focus of the sample to obtain good image quality; Adjust the sample to the desired position and tilt angle. Usually, it needs to be tilted 70° to reduce the path of backscattered electrons emitting from the surface and obtain a sufficiently strong backscattered diffraction signal. Perform backscattered electron analysis on the sample to determine the crystal structure and orientation by capturing the pattern of backscattered electrons in the SEM; Import EBSD patterns into analysis software and perform data analysis, including extraction and processing of information such as crystal structure, crystal orientation and grain boundaries; Based on the analysis results and known crystal structure, interpret the crystallographic characteristics of the sample, such as grain orientation, grain boundary arrangement and other information.

[0035] According to the test, the evolution information of the grains of the conductive film layer of the sample during the bending process is obtained, including the change information of the grains, grain boundaries (grain boundaries, subgrains, phase boundaries, twin boundaries, special interfaces), Schmidt factors, local orientation differences (KAM diagram dislocation network) and other indicators on the plane and cross section; Local misorientation refers to the change in the local misorientation of each individual grain boundary during the deformation of the metal alloy. This change can reflect the evolution of the microstructure and the evolution law of the texture. For example, during the deformation process, the local change of misorientation eventually reaches a certain texture component through crystal rotation, and the local misorientation reflects the evolution trend of crystal rotation.

[0036] The most obvious manifestations of the excellent bending performance of flexible electronics are the high volume content of equiaxed crystals, unclear texture, and relatively light strain accumulation during deformation (evenly distributed dislocations).

[0037] Texture refers to the phenomenon that the orientation distribution of grains in a polycrystal deviates significantly from random distribution and presents a certain regularity during the formation or processing of the polycrystal. This phenomenon is called texture, also known as preferred orientation.

[0038] Texture refers to the fact that when a polycrystalline material is affected by various conditions such as external forces, heat, electricity, magnetism, etc., or by different processing techniques after formation, the grains will be arranged along certain directions, showing a more or less statistically uneven distribution.

[0039] In summary, by obtaining the factors such as structure and material properties that affect the bending performance of flexible electronics, and optimizing the stacking design and the production process of stacking materials accordingly, the bending performance of flexible electronics can be further improved.

[0040] The basic principles of the present disclosure are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present disclosure are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present disclosure. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, and are not limitations. The above details do not limit the present disclosure to the necessity of adopting the above specific details to be implemented.

[0041] In the present disclosure, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. The block diagrams of the devices, devices, equipment, and systems involved in the present disclosure are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0042] Additionally, as used herein, "or" used in a list of items beginning with "at least one" indicates a separate list, so that, for example, a list of "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not mean that the example described is preferred or better than other examples.

[0043] It should also be noted that in the system and method of the present disclosure, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present disclosure.

[0044] Various changes, substitutions, and modifications of the techniques described herein may be made without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of the present disclosure is not limited to the specific aspects of the processes, machines, manufactures, compositions of events, means, methods, and actions described above. Currently existing or later to be developed processes, machines, manufactures, compositions of events, means, methods, or actions that perform substantially the same functions or achieve substantially the same results as the corresponding aspects described herein may be utilized. Thus, the appended claims include such processes, machines, manufactures, compositions of events, means, methods, or actions within their scope.

[0045] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0046] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for characterizing and analyzing the bending performance of a flexible electronic device, characterized in that: include: A finite element simulation model of the flexible electronic bending process is established based on the acquired information of the flexible electronic device; Based on the finite element simulation model, the deformation and stress distribution evolution information of the laminated structure during the bending process of flexible electronics is obtained, and the location and magnitude of the stress concentration area are obtained; Obtaining information on the evolution of grains during the bending process of flexible electronic devices; The bending performance of flexible electronic devices is analyzed based on the deformation and stress distribution evolution information of the laminated structure, the location of the stress concentration area, and the stress magnitude and grain evolution information during the bending process.

2. The method for characterizing and analyzing the bending performance of flexible electronic devices according to claim 1, characterized in that: The obtained information of the flexible electronic device includes: The stacking structure information of flexible electronic devices and the property information of structural materials in the stacking structure.

3. The method for characterizing and analyzing the bending performance of flexible electronic devices according to claim 2, characterized in that: The laminated structure comprises an insulating film layer, a conductive film layer and an adhesive layer.

4. The method for characterizing and analyzing the bending performance of a flexible electronic device according to claim 2, characterized in that: The obtained information of the flexible electronic device also includes: Bending inner corner radius and bending frequency of flexible electronic devices under service conditions.

5. The method for characterizing and analyzing the bending performance of flexible electronic devices according to claim 1, characterized in that: The obtaining of the evolution information of grains during the bending process of the flexible electronic device includes: Based on the bending test of flexible electronic samples, the evolution information of the sample's grains during the bending process is obtained.

6. The method for characterizing and analyzing the bending performance of a flexible electronic device according to claim 5, characterized in that: The method of obtaining the evolution information of the grains of the sample during the bending process based on the bending test of the flexible electronic sample includes: Obtain data from the electron backscatter diffraction test of the conductive film layer of the flexible electronic sample before, during and after bending and breaking using a scanning electron microscope.

7. The method for characterizing and analyzing the bending performance of a flexible electronic device according to claim 1, characterized in that: The method of obtaining the evolution information of the grains of the sample during the bending process based on the flexible electronic sample bending test includes: obtaining the evolution information of the grains of the conductive film layer of the sample during the bending process.

8. The method for characterizing and analyzing the bending performance of a flexible electronic device according to claim 7, characterized in that: The evolution information of the conductive film layer grains during the bending process includes: Information on changes in grains, grain boundaries, Schmidt factors and local misorientation in planes and cross sections.

9. The method for characterizing and analyzing the bending performance of a flexible electronic device according to claim 1, characterized in that: The analysis of the bending performance of the flexible electronic device includes: The excellent bending performance of flexible electronic devices is manifested in relatively small stress values, and the stress concentration areas are mostly located in the middle area of ​​each stacked layer rather than at the junction of each layer; The excellent bending performance of flexible electronics is manifested in the high volume content of equiaxed crystals, unclear texture, and light strain accumulation during deformation.

10. The method for characterizing and analyzing the bending performance of a flexible electronic device according to claim 1, characterized in that: After the step of analyzing the bending performance of the flexible electronic device, the method further includes: Based on the analysis results, the production process of flexible electronic devices, as well as the laminated structure and materials of flexible electronic devices are adjusted.

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