Method for improving the bonding performance of paste circuit and polymer matrix based on laser sintering

Abstract

This invention discloses a method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering. The method includes: generating a laser beam with a spot diameter exceeding the linewidth of the slurry circuit by changing the height of the laser, and then sintering to form a matrix coating layer and the main circuit on the polymer matrix. This invention provides a method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering. It directly obtains high-bonding-performance circuits on FDM-printed high-temperature resistant polymer matrices via laser sintering, avoiding the lengthy and complex substrate surface treatment process, while maintaining the excellent electrical performance of the laser-sintered slurry circuits. Taking silver paste circuits as an example, their resistivity can be controlled below 15 μΩ / cm. The method is simple, low-cost, and very suitable for fabricating 3D printed structural circuits.

Description

Technical Field

[0001] This invention relates to a method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering, belonging to the field of 3D printing technology. Background Technology

[0002] 3D printing technology, due to its outstanding advantages in flexible manufacturing, is gradually being applied to the processing of complex components. However, simply forming single structural parts with supporting and load-bearing functions cannot meet the future development needs of the manufacturing industry, especially in the aerospace field. The future requires the integration of conductive circuits, electronic components, and other elements with the structure to achieve integrated manufacturing of electronic products. This will enable them to possess multiple functions such as information sensing and signal transmission while maintaining a complex shape, thereby achieving the lightweighting and miniaturization of complex functional equipment.

[0003] Currently, research on high-bonding-performance circuits in the field of 3D printed structural circuits is relatively lacking. Traditional 3D printed circuits face bonding failure problems such as detachment and breakage. Researchers also focus primarily on circuit forming accuracy and conductivity, with studies on the bonding performance between the circuit and the substrate limited to complex surface modification methods, thus restricting the development of high-bonding-performance 3D printed structural circuits. Summary of the Invention

[0004] The purpose of this invention is to overcome the technical defects of the existing technology, solve the above-mentioned technical problems, and propose a method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering, thereby realizing a high-bonding-performance circuit manufacturing method based on 3D printing.

[0005] The present invention specifically adopts the following technical solution: a method for improving the bonding performance between slurry circuit and polymer matrix based on laser sintering, the method comprising: generating a beam with a spot diameter exceeding the circuit linewidth by changing the height of the laser for sintering, thereby forming a matrix coating layer and a main circuit on the polymer matrix.

[0006] In a preferred embodiment, the method further includes: the laser increases the spot area by changing the laser defocusing amount, melting the polymer matrix while the laser sinterstens the silver paste, and the polymer matrix cools and solidifies around the main circuit after melting to form a substrate coating layer of the circuit.

[0007] In a preferred embodiment, the method further includes: adjusting the defocusing degree of the laser beam according to the linewidth of the main circuit of the inkjet printing, with the spot diameter being 110% to 130% of the linewidth of the main circuit of the inkjet printing.

[0008] In a preferred embodiment, the method further includes: the main circuit undergoing decoking sintering to form, but not limited to, a mechanical bond with the polymer matrix (3).

[0009] In a preferred embodiment, the method further includes: the cross-sectional dimensions of the main circuit are 0.8mm × 0.35mm.

[0010] In a preferred embodiment, the method specifically includes the following steps:

[0011] Step SS1: Create a matrix model in 3D modeling software, import the matrix model into slicing software, generate the printing path, and print the polymer matrix on the FDM device;

[0012] Step SS2: Fix the printed polymer matrix on the high-viscosity jet printing platform, input the circuit printing path in the main controller, the conductive paste is in the syringe, and the three-axis moving platform controls the jet valve to perform circuit jet printing according to the preset path;

[0013] Step SS3: Measure the line width of the printed circuit under an optical microscope, and then adjust the three-axis moving platform to reduce the laser defocusing amount and increase the spot diameter to achieve 110% to 130% of the circuit line width;

[0014] Step SS4: The laser sinters the circuit according to the jet printing path, ensuring that the slurry circuit melts but does not ablate the polymer matrix while sintering.

[0015] In a preferred embodiment, the method further includes: the polymer matrix printed by FDM does not require special surface treatment.

[0016] In a preferred embodiment, the method further includes: during the laser moving sintering process, changing the height of the laser so that the spot diameter is 110% to 130% of the linewidth of the jet printing paste circuit.

[0017] In a preferred embodiment, the method further includes controlling the scanning speed during laser sintering between 0.3 mm / s and 1 mm / s.

[0018] The beneficial effects achieved by this invention are as follows: The high-bonding-performance circuit manufacturing method designed in this invention is applicable to the field of 3D printing. It uses a multi-material 3D printing process to form the structural circuit, immediately forming the circuit after printing the polymer matrix structure, thus achieving integrated manufacturing of the structural circuit. This high-bonding-performance circuit has low manufacturing cost, fast forming speed, small equipment investment, and few material limitations, providing a feasible technical solution for 3D printing high-bonding-performance circuits. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the principle of the method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering, as described in this invention.

[0020] Figure 2 This is a schematic diagram of the high-performance circuit device fabricated according to the present invention;

[0021] Figure 3 This is a comparative schematic diagram of existing conventional laser focusing sintering circuits and laser defocusing sintering;

[0022] Figure 4 This is a schematic diagram of the SEM image of the circuit and substrate cross-section in laser-focused sintering.

[0023] Figure 5 This is a schematic diagram of the circuit and substrate cross-section of the laser defocusing sintering process using SEM images.

[0024] Figure 6 This is a schematic diagram illustrating the effect of changing the laser defocusing amount on the bonding performance between the sintered circuit and the substrate.

[0025] Figure 7 This is a schematic diagram of the circuit bonding on the substrate surface under laser focal sintering;

[0026] Figure 8 This is a schematic diagram of the circuit bonding on the substrate surface under laser defocusing sintering.

[0027] Figure 9 The results are cross-sectional test results of the bonding strength between laser-focused sintering and laser-defocused sintering.

[0028] The meanings of the markings in the diagram are as follows: 1-Laser, 2-Beam, 3-Polymer matrix, 4-Main circuit, 5-Matrix coating, 6-Injection printing platform, 7-Main controller, 8-Injector, 9-Injection valve, 10-Three-axis moving platform. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0030] Example 1: As Figure 1 and Figure 2 As shown, a method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering includes: generating a beam 2 with a spot diameter exceeding the circuit linewidth by changing the height of the laser 1, and sintering to form a substrate coating layer 5 and a main circuit 4 on the polymer matrix 3.

[0031] In a preferred embodiment, the method further includes: the laser 1 increases the spot area by reducing the laser defocusing amount, and melts the polymer matrix 3 while the laser sinters the silver paste, and the laser focus moves. After melting, the polymer matrix 3 cools and solidifies around the main circuit 4 to form a matrix coating layer 5.

[0032] In a preferred embodiment, the method further includes: the degree of defocusing of the laser beam 2 generated by the laser 1 is adjusted according to the linewidth of the ink body circuit 4 after jet printing, and the spot diameter is 110% to 130% of the linewidth of the ink body circuit 4.

[0033] In a preferred embodiment, the method further includes: the main circuit 4 forming a mechanical bond with the polymer matrix 3 under decoking sintering.

[0034] In a preferred embodiment, the method further includes: the cross-sectional dimensions of the main circuit 4 are 0.8mm × 0.35mm.

[0035] In a preferred embodiment, the method specifically includes the following steps:

[0036] Step SS1: Create a matrix model in 3D modeling software, import the matrix model into slicing software, generate the printing path, and print the polymer matrix 3 on the FDM device;

[0037] Step SS2: Fix the printed polymer matrix 3 onto the high-viscosity jet printing platform 6, input the circuit printing path into the main controller 7, the conductive paste is located in the syringe 8, and the three-axis moving platform 10 controls the jet valve 9 to perform circuit jet printing according to the preset path;

[0038] Step SS3: Measure the line width of the printed circuit under an optical microscope, and then adjust the three-axis moving platform 10 to reduce the laser defocusing amount and increase the spot diameter to achieve a line width of 110% to 130%.

[0039] Step SS4: Laser 1 sinters the circuit according to the jet printing path, ensuring that the slurry circuit melts but does not ablate the polymer matrix while sintering.

[0040] In a preferred embodiment, the method further includes: the polymer matrix 3 printed by FDM does not require special surface treatment.

[0041] In a preferred embodiment, the method further includes: during the moving sintering process of the laser 1, changing the height of the laser 1 so that the spot diameter is 110% to 130% of the linewidth of the jet printing paste circuit.

[0042] In a preferred embodiment, the method further includes controlling the scanning speed during laser sintering between 0.3 mm / s and 1 mm / s.

[0043] Figure 2 To create a schematic diagram of a high-performance circuit device, a three-axis moving platform 10 sprays and prints silver paste circuits along a preset path. The laser 1, installed on the side of the spray valve 9, adjusts the defocusing amount according to the line width of the printed circuit to change the spot diameter and achieve defocusing sintering.

[0044] Figure 3 This is a comparative schematic diagram of conventional laser focus sintering circuit and laser defocus sintering. The focus sintering circuit concentrates the laser focus spot on the silver paste circuit after jet printing, while the defocus sintering expands the laser spot diameter by changing the defocus amount. The laser spot diameter exceeds the linewidth of the silver paste circuit and distributes some of the edge spots on the polymer matrix 3.

[0045] Figure 4 and Figure 5 The images show SEM cross-sectional images of the circuit and substrate after laser-focused sintering and laser-defocused sintering, respectively. In the SEM image of the circuit after laser-focused sintering, large pores are observed at the interface with the polymer substrate 3, while the upper surface layer of the sintered circuit is relatively dense. In contrast, laser-defocused sintering reveals a dense layer of the sintered circuit at the interface with the substrate, where the pore size is smaller and the mechanical bonding characteristics between the circuit and the substrate are present.

[0046] Figure 6 To illustrate the effect of changing the laser defocusing amount on the bonding performance between the sintered circuit and the substrate, a systematic experimental analysis was conducted to study the influence of changing the laser defocusing amount on the bonding performance between the circuit and the substrate at two laser scanning speeds of 0.3 mm / s and 0.7 mm / s. The results show that laser defocusing sintering can significantly improve the bonding performance between the circuit and the substrate.

[0047] Figure 7 and Figure 8 This diagram illustrates the bonding of circuits to a polymer matrix surface under laser focusing sintering and laser defocusing sintering. In laser defocusing sintering, matrix melting can be observed on the matrix surface. The matrix coating layer formed by defocusing sintering increases the contact area between the matrix and the circuit, while in focusing sintering, only the bottom of the circuit contacts the matrix.

[0048] Figure 9 The results of cross-sectional tape tests on the bonding strength of in-focus sintering and defocus sintering show that in-focus sintering, a large area of ​​the circuit detached after the test, while in defocus sintering, the circuit on the substrate hardly detached after the test.

[0049] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0050] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering, characterized in that, The method includes: generating a beam (2) with a spot diameter exceeding the line width of the slurry circuit by changing the height of the laser (1) and sintering it to form a substrate coating layer (5) and a main circuit (4) on a polymer matrix (3). The method further includes: the laser (1) increases the spot area by changing the laser defocusing amount, melts the polymer matrix (3) while the laser sinters the silver paste circuit, and moves along with the laser focus. After melting, the polymer matrix (3) cools and solidifies around the main circuit (4) to form the circuit matrix coating layer (5). The method further includes: the degree of defocusing of the laser beam (2) generated by the laser (1) is adjusted according to the line width of the slurry main circuit (4) after jet printing, and the spot diameter is 110%~130% of the line width of the slurry main circuit (4); The method specifically includes the following steps: Step SS1: Create a matrix model in the 3D modeling software, import the matrix model into the slicing software, generate the printing path, and print the polymer matrix on the FDM device (3). Step SS2: Fix the printed polymer matrix (3) on the high viscosity jet printing platform (6), input the circuit printing path in the main controller (7), the conductive paste is in the syringe (8), and the three-axis moving platform (10) controls the jet valve (9) to perform circuit jet printing according to the preset path; Step SS3: Measure the line width of the printed circuit under an optical microscope, and then adjust the three-axis moving platform (10) to change the laser defocusing amount and increase the spot diameter to achieve a line width of 110%~130%; Step SS4: The laser (1) sinters the circuit according to the jet printing path, ensuring that the slurry circuit melts without burning the polymer matrix (3) while sintering, and forms the matrix coating layer (5) and the main circuit (4) of the circuit on the polymer matrix (3).

2. The method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering according to claim 1, characterized in that, The method further includes: the main circuit (4) is mechanically bonded to the polymer matrix (3) under decoking sintering.

3. The method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering according to claim 1, characterized in that, The method further includes: the cross-sectional dimensions of the main circuit (4) are 0.8mm × 0.35mm.

4. The method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering according to claim 1, characterized in that, The method also includes: the polymer matrix (3) printed by FDM does not need to undergo special surface treatment.

5. The method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering according to claim 1, characterized in that, The method further includes: during the laser (1) moving sintering process, changing the height of the laser (1) to control the spot diameter to 110%~130% of the linewidth of the jet printing paste circuit.

6. The method for improving the bonding performance between slurry circuits and polymer matrices based on laser sintering according to claim 1, characterized in that, The method further includes controlling the scanning speed during laser sintering between 0.3 mm / s and 1 mm / s.

Images