Testing device

Abstract

The utility model relates to the technical field of electronic packaging, and discloses a testing device which comprises a base, a first clamp, a first circuit board, a second clamp, a second circuit board, an adjusting mechanism and a camera shooting mechanism. The first clamp is arranged on the working table; the first circuit board is fixed in the first clamp; the second clamp is arranged above the first clamp at an interval; the second circuit board is fixed in the second clamp, and a solder ball mounting space is formed between the second circuit board and the first circuit board; the adjusting mechanism is installed on the working table and connected with the second clamp, and the adjusting mechanism is used for adjusting the height position and the angle position of the second clamp; the camera shooting mechanism is fixed on the workbench surface and is used for shooting the form of the test solder ball in the solder ball installation space. By adjusting the height position and the angle position of the second clamp, the distance between the two circuit boards at the position of the welding spot is adjusted, so that the distance adjustment is more accurate, the shape change of the welding ball is closer to the real shape when the substrate is warped and deformed, and the accuracy of a test is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic packaging, in particular to a testing device. Background Art

[0002] In a ball grid array (BGA) electronic packaging structure, the chip substrate will warp and deform during the reflow soldering process, resulting in uneven distance distribution between the substrate and the PCB board, and different BGA solder joints at different positions showing different morphological characteristics. And the solder joint morphology will affect the reliability of the chip packaging structure. Currently, when monitoring the solder joint morphology, industrial high and low temperature network cameras are generally arranged in different temperature zones of the reflow furnace, and the morphological changes of the solder joints during the reflow process are recorded in real time through the cameras. However, when testing the morphological changes of the solder joints at different positions of the substrate, only the solder paste thickness at the solder joints can be changed to adjust the distance between the components and the PCB board, and the influence of the distance between the components and the PCB board on the morphological changes of the solder joints is tested. The test factors are single. Moreover, currently, when changing the solder paste thickness, only the solder paste thickness at all solder joint positions can be changed uniformly, and the solder paste thickness at a single solder joint position cannot be controlled individually, which will lead to a large error between the distance between the components and the PCB board at the set solder joint position and the designed distance, resulting in inaccurate test results for the morphological changes of the solder joints. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a testing device to test the morphological changes of solder joints at different positions during the reflow process. A fixture and an adjusting mechanism are set to conveniently adjust the inclination angle of the substrate at different solder joints and the distance between the substrate and the PCB board, and to conveniently control the inclination angle of the substrate and the distance between the substrate and the PCB board at the set solder joint position individually, so that the adjusted distance at the set solder joint position is closer to the designed distance, and the accuracy of the test results is improved.

[0004] To achieve the above purpose, the utility model adopts the following technical solutions:

[0005] The present application provides a testing device, including:

[0006] A base with a horizontally arranged work surface;

[0007] A first fixture arranged on the work surface;

[0008] A first circuit board fixed in the first fixture;

[0009] A second fixture arranged at an interval above the first fixture;

[0010] A second circuit board, fixed within the second fixture and forming a solder ball mounting space for fixing solder balls between the second circuit board and the first circuit board;

[0011] An adjusting mechanism, mounted on the workbench surface and connected to the second fixture, the adjusting mechanism being used to adjust the height position and angular position of the second fixture so as to adjust the spacing between the second circuit board and the first circuit board in the vertical direction; and a camera mechanism, fixed on the workbench surface and disposed at a relatively spaced interval from the first fixture, the imaging range of the camera mechanism at least covering the solder ball mounting space to capture the shape of the solder balls within the solder ball mounting space.

[0012] By placing test solder balls within the solder ball mounting space between the first circuit board and the second circuit board, the test device is placed in a reflow oven to conduct a test on the shape of the solder balls. The adjusting mechanism is used to adjust the height position and angular position of the second fixture, and further adjust the spacing between the second circuit board and the first circuit board at the solder joint position, so that the spacing adjustment is more accurate, and the change in the shape of the solder balls is closer to the true shape when the substrate warps and deforms, improving the accuracy of the test on the shape of solder joints at different positions.

[0013] In some embodiments, the adjusting mechanism includes a first adjusting component and a second adjusting component. The first adjusting component is mounted on the workbench surface, the second adjusting component is assembled on the first adjusting component in a liftable manner, and the second fixture is rotatably mounted on the second adjusting component.

[0014] With the adjusting mechanism in the above form, it is convenient to adjust the height position and angular position of the second circuit board respectively through the first adjusting component and the second adjusting component, facilitating the testing of the change in the shape of the solder balls under a single influencing factor.

[0015] In some embodiments, the first adjusting component includes a first adjusting rod, the first adjusting rod is vertically arranged, and the bottom of the first adjusting rod is rotatably assembled on the workbench surface; an external thread is provided on the first adjusting rod, and the second adjusting component is threadedly assembled on the first adjusting rod.

[0016] Through the threaded assembly of the second adjusting component and the first adjusting rod, the second adjusting component can move along the first adjusting rod, realizing the adjustment of the height position of the second circuit board, with a simple structure, convenient operation, and high adjustment accuracy.

[0017] In some embodiments, the second adjusting component includes a mounting portion and a second adjusting rod. The mounting portion is threadedly assembled on the first adjusting rod, a mounting hole is provided on one side of the mounting portion, one end of the second adjusting rod is rotatably assembled in the mounting hole, and the other end is connected to the second fixture.

[0018] Adjusting the angular position of the second circuit board by rotating the second adjusting rod has a simple structure, is convenient for assembly and manufacture, and is easy to operate.

[0019] In some embodiments, the first fixture is provided with a first limiting groove, the cross-sectional shape of the inner wall of the first limiting groove matches the outer edge contour shape of the first circuit board, the first circuit board is fixed in the first limiting groove, and the pads on the first circuit board face the second circuit board.

[0020] Placing the first circuit board in the first limiting groove, the first circuit board can be limited and fixed by the first limiting groove, which facilitates the installation of the first circuit board, and makes the first circuit board firmly fixed, avoiding the displacement of the first circuit board on the workbench surface, resulting in inaccurate positions of the test solder balls thereon.

[0021] In some embodiments, the outer edge of the first circuit board is adhesively fixed to the inner wall of the first limiting groove.

[0022] Adopting an adhesive method to fix the first circuit board and the first limiting groove facilitates the disassembly and installation of the first circuit board.

[0023] In some embodiments, the second fixture is provided with a second limiting groove, the cross-sectional shape of the inner wall of the second limiting groove matches the outer edge contour shape of the second circuit board, the second circuit board is fixed in the second limiting groove, and the pads on the second circuit board face the first circuit board.

[0024] The second circuit board is limited and fixed by the second limiting groove, so that the second circuit board fits well with the second fixture and is firmly fixed in the second fixture.

[0025] In some embodiments, the second limiting groove penetrates through the second fixture along the thickness direction of the second fixture.

[0026] The second limiting groove is set in a vertically through groove structure form. The upper slot opening of the second limiting groove is convenient for placing the second circuit board into the second limiting groove from top to bottom. The lower slot opening of the second limiting groove facilitates the test solder balls in the solder ball installation space to contact both the first circuit board and the second circuit board, and also facilitates the installation and disassembly of the second circuit board in the second limiting groove.

[0027] In some embodiments, the second fixture includes a plurality of clamping portions, the plurality of clamping portions are sequentially connected end to end to enclose the second limiting groove, and one of the plurality of clamping portions is connected to the adjusting mechanism.

[0028] The second fixture is set in a structural form where multiple clamping parts are connected, which facilitates the formation of a second limiting groove with an arbitrary shape in the second fixture, enabling the shape of the second limiting groove to match the shape of the second circuit board, and facilitating the clamping and fixing of the second circuit board.

[0029] In some embodiments, the outer edge of the second circuit board is adhesively fixed to the inner wall of the groove of the second limiting groove.

[0030] Adopting the adhesive method to fix the second circuit board and the second limiting groove facilitates the disassembly and installation of the second circuit board.

[0031] This application also provides a design method for a packaging structure. The packaging structure includes a chip, a substrate, and a printed circuit board. The chip is disposed on the substrate and electrically connected to the substrate. The printed circuit board is disposed on the side of the substrate facing away from the chip, and the printed circuit board is connected to the substrate through solder balls. The design method includes the following steps:

[0032] Obtain the structural parameters of the substrate, the structural parameters of the printed circuit board, and the structural parameters of the solder balls;

[0033] Fabricate the first circuit board of the above test device according to the structural parameters of the printed circuit board, fabricate the second circuit board of the above test device according to the structural parameters of the substrate, and fabricate test solder balls according to the structural parameters of the solder balls;

[0034] Test the morphology of the test solder balls between the first circuit board and the second circuit board through the test device, and obtain the morphology image of the test solder balls by shooting with a camera mechanism;

[0035] According to the morphology image of the test solder balls, obtain the morphology parameters of the test solder balls. The morphology parameters are the uniformity index values of the outer shape of the test solder balls;

[0036] Change the position of the test solder balls between the first circuit board and the second circuit board, repeat the step of testing the morphology of the solder balls, and obtain the morphology parameters of each test solder ball on the second circuit board;

[0037] Adjust the structural parameters of each solder ball according to the morphology parameters of each test solder ball on the second circuit board to obtain the solder ball arrangement between the substrate and the printed circuit board.

[0038] Test the morphology parameters of the solder balls through the test device, obtain the morphological changes of the test solder balls in the reflow soldering process, determine the arrangement mode of the solder balls through the morphological changes of the test solder balls at each position, realize the auxiliary design of the solder ball arrangement in the packaging structure, and is conducive to improving the reliability of the packaging structure.

[0039] In some embodiments, the design method further includes: slicing and detecting the test solder balls to obtain internal defects of the test solder balls, and the morphological parameters further include internal defect index values of the test solder balls.

[0040] By detecting the internal defects of the test solder balls and combining the changes in the appearance morphology to judge the changes in the solder ball morphology, the accuracy of the solder ball morphology test of the test solder balls is improved, and then it is convenient to optimize the package structure according to the changes in the solder ball morphology.

[0041] In some embodiments, the step of testing the morphology of the test solder balls between the first circuit board and the second circuit board by the test device includes:

[0042] Placing the test solder balls at a set position on the first circuit board;

[0043] Adjusting the height position and inclination angle of the second circuit board so that the test solder balls are in contact with the first circuit board and the second circuit board;

[0044] Turning on the camera mechanism and sending the entire test device into a reflow oven for the reflow process;

[0045] Obtaining the images of the morphological changes of the test solder balls taken by the camera mechanism.

[0046] Testing the morphology of the test solder balls by the test device facilitates visually observing the uniformity of the morphological changes of the solder balls through the images of the morphological changes of the test solder balls taken by the camera mechanism. Moreover, by changing the set position of the test solder balls on the first circuit board, the morphological changes of the solder balls at different positions can also be tested, thus facilitating the arrangement of the solder balls in the package structure.

[0047] In some embodiments, the design method further includes:

[0048] Changing the structural parameters of the solder balls, and repeating the steps of manufacturing the test solder balls and the steps of testing the morphology of the solder balls;

[0049] Comparing the changes in the morphological parameters of the test solder balls before and after changing the structural parameters of the solder balls;

[0050] Taking the structural parameters of the solder balls corresponding to the minimum of the changes in the morphological parameters of the test solder balls as the optimal structural parameters of the solder balls.

[0051] Using the above steps to obtain the optimal structural parameters of the solder balls enables the solder balls in the package structure to have smaller morphological changes and better uniformity of the appearance morphology after the reflow soldering process, enabling the solder balls to better match the thermal expansion between the substrate and the printed circuit board, improving the solder joint quality, and thus improving the reliability of the package structure.

[0052] In some embodiments, the design method further includes:

[0053] Changing the structural parameters of the substrate or the structural parameters of the printed circuit board, and repeating the steps of manufacturing the first circuit board and the second circuit board and the step of testing the solder ball morphology;

[0054] Comparing the changes in the morphological parameters of the test solder ball before and after changing the structural parameters of the substrate or the printed circuit board;

[0055] Taking the structural parameters of the substrate or the printed circuit board corresponding to the minimum change in the morphological parameters of the test solder ball as the optimal structural parameters of the substrate or the printed circuit board.

[0056] By optimizing the design of the structural parameters of the substrate and the printed circuit board, the reliability of the package structure can be improved.

[0057] In some embodiments, the step of obtaining the morphological parameters of the test solder ball according to the morphological image of the test solder ball includes:

[0058] Preprocessing the morphological image of the test solder ball;

[0059] Performing edge detection on the preprocessed morphological image to identify the boundary position of the test solder ball;

[0060] Performing threshold segmentation on the morphological image to obtain the test solder ball region;

[0061] Obtaining the morphological parameters of the test solder ball according to the segmented test solder ball region.

[0062] Segmenting the test solder ball region from the morphological image not only facilitates the intuitive observation of the appearance morphology of the solder ball, but also facilitates the comparison of the appearance morphologies of different test solder balls.

[0063] In some embodiments, the structural parameters of the solder ball at least include the shape, diameter, and material of the solder ball.

[0064] By setting the structural parameters of the solder ball, it is convenient to select a more suitable solder ball in the package structure design, thereby improving the reliability of the package structure.

[0065] In some embodiments, the structural parameters of the substrate at least include the size of the substrate, the size of the solder pads on the substrate, the ink opening position, and the ink coating thickness.

[0066] By setting the structural parameters of the substrate and optimizing the design of the substrate, it is convenient to improve the performance of the substrate in the package structure, thereby improving the overall reliability of the package structure.

[0067] In some embodiments, the structural parameters of the printed circuit board at least include the size of the printed circuit board, the size of the pads on the printed circuit board, the ink opening position, and the ink coating thickness.

[0068] By setting the structural parameters of the printed circuit board, the printed circuit board is optimized, which is convenient for improving the performance such as the signal transmission speed and heat transfer speed of the printed circuit board, and further improving the overall reliability of the packaging structure.

[0069] Compared with the prior art, the beneficial effect of the test device according to the embodiment of the present invention lies in:

[0070] The test device according to the embodiment of the present invention includes a base, a first fixture, a first circuit board, a second fixture, a second circuit board, an adjusting mechanism, and a camera mechanism. The first circuit board is fixed by the first fixture, and the second circuit board is fixed by the second fixture, and a solder ball installation space is formed between the first circuit board and the second circuit board. Thus, the first circuit board can be used to simulate the PCB board in the chip packaging structure, and the second circuit board can be used to simulate the substrate in the chip packaging structure. The height position and angular position of the second fixture can be adjusted by the adjusting mechanism, so as to adjust the distance between the first circuit board and the second circuit board in the vertical direction and the inclination angle of the second circuit board, simulating the warping deformation of the substrate. When conducting a test, the solder ball is placed at a set position on the first circuit board. The height position and angular position of the second fixture are adjusted by the adjusting mechanism to adjust the second circuit board to a set height and a set inclination angle, so that the solder ball is placed in the solder ball installation space and remains in contact with the first circuit board and the second circuit board, simulating the state of the solder ball at the set position when the second circuit board is at the set height and set inclination angle. The whole test device is placed in a reflow oven for the reflow process. The morphological changes of the solder ball during the reflow process are photographed by the camera mechanism, and the image of the morphological changes of the solder joint at the set position can be obtained. When changing the position of the solder ball, the height and inclination angle of the second circuit board are readjusted by the adjusting mechanism, so that the distance between the second circuit board and the first circuit board in the vertical direction and the inclination angle of the second circuit board match the position of the solder ball, so that the morphological tests of the solder joints at different positions can be carried out. Since the height position and angular position of the second fixture are adjusted by the adjusting mechanism of the present application, and then the distance between the second circuit board and the first circuit board at the solder joint position is adjusted, it is convenient to separately control the inclination angle of the substrate and the distance between the substrate and the PCB board at the set solder joint position, making the adjustment of the distance at each solder joint position more accurate, and it is convenient to separately control the inclination angle of the substrate and the distance between the substrate and the PCB board at the set solder joint position, facilitating the accurate distinction of the morphological changes of the solder balls at different positions, making the morphological changes of the solder balls closer to the true morphology when the substrate warps, and improving the accuracy of the morphological tests of the solder joints at different positions. Description of the Drawings

[0071] Figure 1 It is a schematic diagram of the reflow soldering joint morphology test device described in the embodiments of the present application;

[0072] Figure 2 is Figure 1 the front view schematic diagram of

[0073] Figure 3 is Figure 1 the side view schematic diagram of

[0074] Figure 4 is Figure 1 the top view schematic diagram of

[0075] Figure 5 is Figure 4 the sectional view taken along the line A - A in

[0076] Figure 6 It is a schematic diagram of another perspective of the reflow soldering joint morphology test device described in the embodiments of the present application.

[0077] Reference numerals in the figure:

[0078] 1, base; 11, workbench surface; 2, first fixture; 21, first limiting groove; 3, first circuit board; 4, second fixture; 41, clamping part; 411, second limiting groove; 5, second circuit board; 51, solder ball installation space; 6, adjusting mechanism; 61, first adjusting component; 611, first adjusting rod; 62, second adjusting component; 621, installation part; 622, second adjusting rod; 7, camera mechanism; 8, test solder ball. Detailed implementation manners

[0079] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0080] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", "bonding" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0081] The following will, with reference to the accompanying drawings and embodiments, describe in further detail the specific implementation manners of the present utility model. The following embodiments are used to illustrate the present utility model, but are not intended to limit the scope of the present utility model.

[0082] Referring to Figure 1 - Figure 6 As shown, an embodiment of the present utility model provides a testing device, which includes a base 1, a first fixture 2, a first circuit board 3, a second fixture 4, a second circuit board 5, an adjusting mechanism 6 and a camera mechanism 7. The base 1 has a horizontally arranged working surface 11; the first fixture 2 is arranged on the working surface 11; the first circuit board 3 is fixed in the first fixture 2; the second fixture 4 is arranged at an interval above the first fixture 2; the second circuit board 5 is fixed in the second fixture 4 and a solder ball installation space 51 for fixing solder balls is formed between the second circuit board 5 and the first circuit board 3. The solder balls in the solder ball installation space 51 are hereinafter referred to as test solder balls; the adjusting mechanism 6 is installed on the working surface 11 and is connected to the second fixture 4. The adjusting mechanism 6 is used to adjust the height position and angular position of the second fixture 4 so as to adjust the distance between the second circuit board 5 and the first circuit board 3 in the vertical direction; the camera mechanism 7 is fixed on the working surface 11 and is arranged at an interval relative to the first fixture 2. The imaging range of the camera mechanism 7 at least covers the solder ball installation space 51 to capture the morphology of the test solder balls 8 in the solder ball installation space 51.

[0083] A solder ball mounting space is formed between the first circuit board 3 and the second circuit board 5. The first circuit board 3 can be used to simulate the PCB board in the chip packaging structure, and the second circuit board 5 can be used to simulate the substrate in the chip packaging structure, so that the solder ball morphology in the chip packaging structure can be simulated and tested. The height position and angular position of the second fixture 4 can be adjusted by the adjusting mechanism 6, so as to adjust the distance between the first circuit board 3 and the second circuit board 5 in the vertical direction and the inclination angle of the second circuit board 5, simulating the warping deformation of the substrate. During the test, the test solder ball 8 is placed at the set position on the first circuit board 3. The height position and angular position of the second fixture 4 are adjusted by the adjusting mechanism 6 to adjust the second circuit board 5 to the set height and set inclination angle, so that the test solder ball 8 is placed in the solder ball mounting space 51 and is in contact with the first circuit board 3 and the second circuit board 5, simulating the state of the test solder ball 8 at the set position when the second circuit board 5 is at the set height and set inclination angle. The whole test device is placed in a reflow oven for the reflow process. The change in the solder ball morphology during the reflow process is photographed by the imaging mechanism 7, and the solder joint morphology change image at the set position can be obtained. When changing the position of the test solder ball 8, the height and inclination angle of the second circuit board 5 are readjusted by the adjusting mechanism 6 so that the distance between the second circuit board 5 and the first circuit board 3 in the vertical direction and the inclination angle of the second circuit board 5 match the position of the test solder ball 8, so that the solder joint morphology at different positions can be tested. Since the present application adjusts the height position and angular position of the second fixture 4 through the adjusting mechanism 6, and further adjusts the distance between the second circuit board 5 and the first circuit board 4 at the solder joint position, the adjustment of the distance at each solder joint position is more accurate, and it is convenient to separately control the inclination angle of the substrate and the distance between the substrate and the PCB board at the set solder joint position, facilitating the accurate distinction of the solder ball morphology changes at different positions, making the solder ball morphology change closer to the true morphology when the substrate warps, and improving the accuracy of the test of the solder joint morphology at different positions.

[0084] Refer to Figure 1 - Figure 6 As shown, in some embodiments, the base 1 is in the shape of a cuboid and is made of cast iron material, having good rigidity. As the bearing base of the whole test device, it provides an installation space for the first fixture 2, the adjusting mechanism 6 and the imaging mechanism 7. The upper surface of the base 1 forms a workbench surface 11 to keep the whole test device stable. The imaging mechanism 7 is a high-temperature resistant camera. The imaging mechanism 7 is arranged at one end of the base 1 and fixed on the workbench surface 11. The imaging mechanism 7 is arranged facing the solder ball mounting space 51. The imaging mechanism 7 is integrally arranged on the workbench surface 11 of the base 1, so that the imaging mechanism 7 can move synchronously with the base 1, ensuring that the imaging angle of the imaging mechanism 7 is fixed and guaranteeing the stability of the imaging of the imaging mechanism 7.

[0085] Refer to Figure 1 andFigure 5 As shown, in some embodiments, the first fixture 2 is bonded to the workbench surface 11 by a high-temperature resistant glue. The first fixture 2 is provided with a first limiting groove 21. The cross-sectional shape of the inner part of the first limiting groove 21 matches the outer edge contour shape of the first circuit board 3. The first circuit board 3 is fixed in the first limiting groove 21 and the pads on the first circuit board 3 face the second circuit board 5. The test solder balls 8 are fixed on the first circuit board 3. The first limiting groove 21 plays a role in limiting and fixing the first circuit board 3, making the first circuit board 3 firmly fixed and preventing the first circuit board 3 from displacing on the workbench surface 11, which may cause inaccurate positions of the test solder balls thereon. When the first circuit board 3 is rectangular, correspondingly, the cross-sectional shape of the inner part of the first limiting groove 21 is rectangular. Moreover, the size of the first circuit board 3 matches the cross-sectional size of the inner part of the first limiting groove 21, so that the outer edge of the first circuit board 3 fits against the groove wall of the first limiting groove 21, and the corner positions of the first circuit board are opposite to the corner positions of the first limiting groove 21, facilitating the positioning of the first circuit board 3 in the first limiting groove 21.

[0086] In some embodiments, the outer edge of the first circuit board 3 is adhesively fixed to the inner wall of the first limiting groove 21, which facilitates the disassembly and installation of the first circuit board 3. Moreover, the surface of the first circuit board 3 will not be damaged during the disassembly and installation process. Optionally, glue can be applied at the corner positions of the first circuit board 3 to bond the first circuit board 3 inside the first fixture 2. When disassembling, removing the glue can detach the first circuit board 3 from the first fixture 2. Applying glue only at the corner positions reduces the amount of glue applied and facilitates disassembly and installation.

[0087] Refer to Figure 1 - Figure 6 As shown, in some embodiments, the second fixture 4 is provided with a second limiting groove 411. The cross-sectional shape of the inner part of the second limiting groove 411 matches the outer edge contour shape of the second circuit board 5. The second circuit board 5 is fixed in the second limiting groove 411 and the pads on the second circuit board 5 face the first circuit board 3. The second circuit board 5 is limited and fixed by the second limiting groove 411. The notch of the second limiting groove 411 faces the first circuit board 3 inside the first fixture 1, facilitating the contact of the test solder balls 8 with both the first circuit board 3 and the second circuit board 5. The second circuit board 5 is rectangular, the second limiting groove 411 is rectangular, and the size of the second circuit board 5 matches the cross-sectional size of the inner part of the second limiting groove 411, making the edge of the second circuit board 5 fit against the groove wall of the second limiting groove 411, and the corner positions of the second circuit board 5 are opposite to the inner corner positions of the second limiting groove 411, facilitating the positioning of the second circuit board 5 in the second limiting groove 411 and enabling good cooperation between the second circuit board 5 and the second fixture 4.

[0088] Refer to Figure 5As shown, in some embodiments, the second limiting groove 411 penetrates through the second fixture 4 along the thickness direction of the second fixture 4. By setting the second limiting groove 411 as a vertically penetrating groove structure, the upper notch of the second limiting groove 411 facilitates placing the second circuit board 5 into the second limiting groove 411 from top to bottom, and the lower notch of the second limiting groove 411 facilitates the test solder balls 8 in the solder ball installation space 51 to contact both the first circuit board 3 and the second circuit board 5. Moreover, since the pads of the second circuit board 5 need to face the first circuit board 3, setting the second limiting groove 411 as a through groove structure also facilitates removing the second circuit board 5 from the upper notch, facilitating the replacement of the second circuit board 5.

[0089] Referring to Figure 4 and Figure 5 As shown, in some embodiments, the second fixture 4 includes a plurality of clamping portions 41. The plurality of clamping portions 41 are connected end to end in sequence and enclose to form the second limiting groove 411. One of the plurality of clamping portions 41 is connected to the adjusting mechanism 6. By setting the second fixture 4 as a structure formed by connecting a plurality of clamping portions 41, it not only facilitates the manufacturing and forming of the second fixture 4, but also enables the plurality of clamping portions 41 to enclose to form the second limiting groove 411 with an arbitrary cross-sectional shape, facilitating the adaptation of the cross-sectional shape of the inner wall of the second limiting groove 411 to the cross-sectional shape of the second circuit board 5. By driving the clamping portion 41 connected thereto to lift or rotate through the adjusting mechanism 6, the overall lifting or rotation of the second fixture 4 is driven. The clamping portion 41 is columnar. The plurality of clamping portions 41 can be fixedly connected or integrally formed. When installing the second circuit board 5, the second circuit board 5 is perpendicular to the side walls of the respective clamping portions 41. Figure 4 As shown in, there are four clamping portions 41, and the four clamping portions 41 enclose to form a rectangular second limiting groove 411.

[0090] In some embodiments, the outer edge of the second circuit board 5 is adhesively fixed to the inner wall of the groove of the second limiting groove 411. Specifically, glue can be applied at the edge of the second circuit board 5 to adhesively fix the second circuit board 5 to the second fixture 4. After the test is completed, the glue is removed, and the second circuit board 5 can be removed from the second fixture 4.

[0091] In some embodiments, both the first circuit board 3 and the second circuit board 5 are circuit boards customized according to the requirements of the test experiment, such that parameters such as the pad size, pad setting method, and solder mask opening on the first circuit board 3 are consistent with the relevant parameters on the PCB board of the package structure to be simulated, and parameters such as the pad size, pad setting method, and solder mask opening on the second circuit board 5 are consistent with the relevant parameters on the substrate of the package structure to be tested and simulated, thereby improving the accuracy of the solder joint morphology test in the package structure. By changing the setting of a single parameter on the first circuit board 3 or the second circuit board 5, a test experiment can be conducted on the change in solder ball morphology caused by this parameter, and the influence of this parameter on the change in solder ball morphology can be obtained, thereby providing a reference basis for the reliability design of the package structure. Therefore, the present application can not only simulate the influence of the warping deformation of the substrate on the change in solder joint morphology, but also simulate the influence of the change in the relevant setting method on the substrate or the PCB board on the change in solder joint morphology, such that the factors for the solder joint morphology test are no longer single, but rather the influence of multiple influencing factors on the solder joint morphology can be tested respectively. It should be noted that during each test process, only a single influencing factor is changed, and under a single variable, the influence of this influencing factor on the change in solder joint morphology is tested.

[0092] Referring to Figure 1 - Figure 6 As shown, in some embodiments, the adjusting mechanism 6 includes a first adjusting component 61 and a second adjusting component 62. The first adjusting component 61 is installed on the workbench surface 11, the second adjusting component 62 is assembled on the first adjusting component 61 in a liftable manner, and the second fixture 4 is rotatably installed on the second adjusting component 62. By driving the second adjusting component 62 to move up and down through the first adjusting component 61, the second fixture 4 is driven to move up and down synchronously, adjusting the height position of the second fixture 4, thereby adjusting the height position of the second circuit board 5 and the distance between the second circuit board 5 and the first circuit board 3. By driving the second fixture 4 to rotate through the second adjusting component 62, the angular position of the second fixture 4 is adjusted, thereby adjusting the angular position of the second circuit board 5 to simulate the degree of warping deformation on the substrate side at the position where the solder ball 8 is located. The adjusting mechanism 6 is configured in the combined form of the first adjusting component 61 and the second adjusting component 62, which facilitates separately adjusting the height position and the angular position of the second fixture 4, and is convenient for testing the change in solder ball morphology under a single influencing factor.

[0093] Referring to Figure 1 - Figure 6As shown, in some embodiments, the first adjustment assembly 61 includes a first adjustment rod 611. The first adjustment rod 611 is vertically arranged, and the bottom of the first adjustment rod 611 is rotatably assembled on the workbench surface 11 and perpendicular to the workbench surface 11. The first adjustment rod 611 is provided with an external thread, and the second adjustment assembly 62 is threadedly assembled on the first adjustment rod 611. Since the second adjustment assembly 62 is threadedly assembled with the first adjustment rod 611, when the first adjustment rod 611 is rotated, the second adjustment assembly 62 can be driven to move along the first adjustment rod 611. Also, since the first adjustment rod 611 is vertically arranged, the movement of the second adjustment assembly 62 along the first adjustment rod 611 is a lifting movement, thereby realizing the lifting of the second fixture 4 and the second circuit board 5 therein. The first adjustment rod 611 is a lead screw and rotates around its own central axis. The first adjustment rod 611 is perpendicular to the workbench surface 11.

[0094] Refer to Figure 1 - Figure 6 As shown, in some embodiments, the second adjustment assembly 62 includes a mounting portion 621 and a second adjustment rod 622. The mounting portion 621 is threadedly assembled on the first adjustment rod 611. One side of the mounting portion 621 is provided with a mounting hole, one end of the second adjustment rod 622 is rotatably assembled in the mounting hole, and the other end is connected to the second fixture 4. By rotating the first adjustment rod 611, the mounting portion 621 moves along the first adjustment rod 611, driving the second adjustment rod 622 and the second fixture 4 to move synchronously, thereby adjusting the height position of the second fixture 4. By rotating the second adjustment rod 622, the second fixture 4 is driven to rotate synchronously, adjusting the angular position of the second fixture 4. The structure is simple and the operation is convenient. The mounting portion 621 can be a nut, provided with an internal thread, and threadedly assembled with the first adjustment rod 611. The second adjustment rod 622 and the second fixture 4 can be fixedly welded. Specifically, the second adjustment rod 622 is fixed to one of the clamping portions 41 of the second fixture 4. In order to facilitate the position fixing after the second adjustment rod 622 rotates, the second adjustment assembly 62 further includes a locking member to lock the position of the second adjustment rod 622 in the mounting hole. For example, the locking member is threadedly assembled on the hole wall of the mounting hole and passes through the hole wall to abut against the second adjustment rod 622.

[0095] Optionally, an angular scale can be provided along the circumferential direction of the end face of one end of the mounting hole, and an indicating mark is provided on the second adjustment rod 62. The rotation angle of the second adjustment rod 62 can be accurately controlled by the angular scale to which the indicating mark rotates.

[0096] The working process of the above test device is as follows:

[0097] Fix the first circuit board 3 in the first fixture 2 and fix the second circuit board 5 in the second fixture 4; Place the test solder balls 8 at the set positions on the first circuit board 3; According to the set positions of the test solder balls 8, adjust the height position and angular position of the second circuit board 5 through the adjusting mechanism 6 (wherein, for different set positions of the test solder balls 8, the height position and angular position of the second circuit board 5 are different. The closer the test solder balls 8 are to the middle position of the first circuit board 3, the closer the second circuit board 3 is to the horizontal; The closer the test solder balls 8 are to the edge position of the first circuit board 3, the greater the inclination angle of the second circuit board 3, so as to simulate the warping deformation of the substrate at the edge position), so that the test solder balls 8 are in good contact with the first circuit board 3 and the second circuit board 5. Turn on the imaging mechanism and place the whole test device into the reflow oven. After reflow is completed, take out the test device, analyze and process the images of the solder balls during the reflow process captured by the imaging mechanism, obtain the uniformity of the morphological changes of the solder joints during the reflow process at this height and inclination angle, and single solder balls can also be sliced to observe their internal defects. After changing the set positions of the test solder balls 8, according to the set positions, readjust the height position and angular position of the second circuit board 5, and repeat the steps of the reflow process and photographing the morphological changes of the test solder balls 8 to simulate the morphological changes of the test solder balls 8 at the set positions under the current warping.

[0098] When the test device of the present application conducts a test, by keeping the reflow soldering process unchanged, the morphological changes of the solder balls at different solder joint positions can be realized; When the positions of the solder balls remain unchanged, the influence of the reflow soldering process on the morphological changes of the solder balls can also be tested.

[0099] The present application also provides a design method for a packaging structure. The packaging structure includes a chip, a substrate, and a printed circuit board. The chip is disposed on the substrate and electrically connected to the substrate. The printed circuit board is disposed on the side of the substrate facing away from the chip, and the printed circuit board is connected to the substrate through solder balls; The design method includes the following steps:

[0100] Obtain the structural parameters of the substrate, the structural parameters of the printed circuit board, and the structural parameters of the solder balls;

[0101] Fabricate the first circuit board 3 of the above test device according to the structural parameters of the printed circuit board, fabricate the second circuit board 5 of the above test device according to the structural parameters of the substrate, and fabricate the test solder balls 8 according to the structural parameters of the solder balls, so that the above test device can be used to conduct a reflow soldering process test on the packaging structure;

[0102] Test the morphology of the test solder balls 8 between the first circuit board 3 and the second circuit board 5 through the test device, and obtain the morphological images of the test solder balls 8 by photographing through the imaging mechanism 7;

[0103] According to the morphological image of the test solder ball 8, morphological parameters of the test solder ball 8 are obtained. The morphological parameters are the uniformity index values of the outer shape of the test solder ball 8, and the uniformity of the appearance shape of the test solder ball 8 is characterized by the uniformity index values. The worse the uniformity, the worse the morphology of the test solder ball 8;

[0104] Change the position of the test solder ball 8 between the first circuit board 3 and the second circuit board 5, and repeat the steps of testing the morphology of the solder ball to obtain the morphological parameters of each test solder ball 8 on the second circuit board 5;

[0105] Adjust the structural parameters of each solder ball according to the morphological parameters of each test solder ball 8 on the second circuit board 5 to obtain the solder ball arrangement between the substrate and the printed circuit board. For example, solder balls may not be arranged at positions where the morphological uniformity of the test solder ball 8 is poor. Or, at the edge position of the circuit board, the morphological uniformity of the test solder ball 8 is poor, then solder balls with a larger diameter can be considered to be arranged here, etc., so as to determine the solder ball arrangement method. It should be noted that after adjusting the structural parameters of each solder ball, the corresponding test solder ball 8 can be remade for testing, and finally the structural parameters of the test solder ball 8 with better morphological uniformity are the optimal structural parameters of the solder ball.

[0106] In this application, the morphological parameters of the solder ball are tested through a test device to obtain the morphological changes of the test solder ball 8 in the reflow soldering process. By the morphological changes of the test solder ball 8 at each position, the solder ball arrangement method is determined, so as to realize the auxiliary design of the solder ball arrangement in the packaging structure.

[0107] In some embodiments, the design method further includes: performing slicing detection on the test solder ball 8 to obtain internal defects of the test solder ball 8. The morphological parameters further include the internal defect index values of the test solder ball 8. The internal defect degree of the test solder ball 8 is characterized by the internal defect index values. The fewer the internal defects, the closer the morphology of the test solder ball 8 is to being qualified. By detecting the internal defects of the test solder ball 8 and combining the changes in the appearance morphology, the changes in the solder ball morphology are judged, the accuracy of the solder ball morphology test of the test solder ball 8 is improved, and then it is convenient to optimize the packaging structure according to the changes in the solder ball morphology. It should be noted that the slicing detection method for the solder ball is a prior art, and this application will not elaborate on it in detail.

[0108] In some embodiments, the steps of testing the morphology of the test solder balls 8 between the first circuit board 3 and the second circuit board 5 by a test device include: placing the test solder balls 8 at set positions on the first circuit board 3; adjusting the height position and inclination angle of the second circuit board 5 so that the test solder balls 8 are in contact with both the first circuit board 3 and the second circuit board 5; turning on the imaging mechanism 7 and sending the entire test device into a reflow oven for the reflow process; and obtaining the images of the morphological changes of the test solder balls 8 captured by the imaging mechanism 7. Testing the morphology of the test solder balls 8 by the test device is convenient for visually observing the uniformity of the morphological changes of the solder balls through the images of the morphological changes of the test solder balls 8 captured by the imaging mechanism 7. On the other hand, by changing the set positions of the test solder balls 8 on the first circuit board 3, the morphological changes of the solder balls at different positions can also be tested, thus facilitating the arrangement of the solder balls in the package structure. Among them, when adjusting the height position and inclination angle of the second circuit board 5, the closer the test solder balls 8 are to the middle position of the first circuit board 3, the closer the second circuit board 5 is to the horizontal; the closer the test solder balls 8 are to the edge position of the first circuit board 3, the greater the inclination angle of the second circuit board 5, so as to simulate the warping deformation of the substrate at the edge position.

[0109] In some embodiments, the structural parameters of the solder balls at least include the shape, diameter, and material of the solder balls, which is convenient for selecting more suitable solder balls and improving the reliability of the package structure. The design method further includes: changing the structural parameters of the solder balls, repeating the manufacturing steps of the test solder balls 8 and the steps of testing the morphology of the solder balls; comparing the changes in the morphological parameters of the test solder balls 8 before and after changing the structural parameters of the solder balls; and taking the structural parameters of the solder balls corresponding to the smallest change in the morphological parameters of the test solder balls 8 as the optimal structural parameters of the solder balls. Among them, the change in the morphological parameters of the test solder balls 8 refers to the difference in the morphology of the test solder balls 8 before and after the reflow process. After the reflow process, the better the uniformity of the appearance morphology of the test solder balls 8, the smaller the change in the morphological parameters. Correspondingly, after the reflow process, the worse the uniformity of the appearance morphology of the test solder balls 8, the greater the change in the morphological parameters. By adopting the above steps to obtain the optimal structural parameters of the solder balls, the morphological changes of the solder balls in the package structure are smaller after the reflow soldering process, and the uniformity of the appearance morphology of the solder balls is better, so that the solder balls can better match the thermal expansion between the substrate and the printed circuit board, improve the solder joint quality, and thus improve the reliability of the package structure. It should be noted that when changing the structural parameters of the solder balls, only a single structural parameter of the solder balls is changed in each test. For example, when changing the diameter of the test solder balls 8, the shape and material of the test solder balls 8 remain unchanged, or only the material of the solder balls is changed, while the shape and diameter of the test solder balls 8 remain unchanged. The change in the morphological parameters of the test solder balls 8 specifically refers to the morphological difference of the solder balls before and after the reflow soldering process.

[0110] In some embodiments, the structural parameters of the substrate at least include the size of the substrate, the size of the pads on the substrate, the ink window position, and the ink coating thickness. The structural parameters of the printed circuit board at least include the size of the printed circuit board, the size of the pads on the printed circuit board, the ink window position, and the ink coating thickness. By optimizing the design of the substrate and the printed circuit board based on the above structural parameters, the performance such as the signal transmission speed, stability, and heat transfer efficiency of the substrate and the printed circuit board can be improved.

[0111] The design method further includes: changing the structural parameters of the substrate or the structural parameters of the printed circuit board, repeating the steps of manufacturing the first circuit board 3 and the second circuit board 5, and the step of testing the morphology of the solder balls; comparing the changes in the morphological parameters of the solder balls 8 before and after changing the structural parameters of the substrate or the printed circuit board; taking the structural parameters of the substrate or the printed circuit board corresponding to the smallest change in the morphological parameters of the tested solder balls 8 as the optimal structural parameters of the substrate or the printed circuit board. By using the above steps to obtain the optimal structural parameters of the substrate or the printed circuit board, the design of the substrate and the printed circuit board in the packaging structure is optimized, so that the substrate, the printed circuit board and the solder balls manufactured according to the optimal structural parameters are matched, and the formed packaging structure has high reliability.

[0112] In some embodiments, the step of obtaining the morphological parameters of the tested solder balls 8 from the morphological image of the tested solder balls 8 includes: preprocessing the morphological image of the tested solder balls 8; performing edge detection on the preprocessed morphological image to identify the boundary position of the tested solder balls 8; performing threshold segmentation on the morphological image to obtain the region of the tested solder balls 8; and obtaining the morphological parameters of the tested solder balls 8 according to the segmented region of the tested solder balls 8. By processing the morphological image of the tested solder balls 8 and segmenting the region of the tested solder balls 8, it is convenient to more intuitively observe the change in the appearance morphology of the tested solder balls 8, improve the accuracy of the obtained morphological parameters, and facilitate the comparison of the appearance morphologies of multiple tested solder balls 8.

[0113] It should be noted that the above methods of edge detection and threshold segmentation are all prior arts, and the present application will not elaborate on them in detail.

[0114] In summary, the embodiment of the present utility model provides a testing device. The first circuit board 3 is used to simulate the PCB board in the chip packaging structure, and the second circuit board 5 is used to simulate the substrate in the chip packaging structure, so as to simulate and test the shape of the solder balls in the chip packaging structure. During the test, the test solder ball 8 is placed at a set position on the first circuit board 3. The height position and angular position of the second fixture 4 are adjusted through the adjusting mechanism 6 to adjust the second circuit board 5 to a set height and a set inclination angle, so that the test solder ball 8 is placed in the solder ball installation space 51 and remains in contact with the first circuit board 3 and the second circuit board 5, simulating the state of the test solder ball 8 at this set position when the second circuit board 5 is at this set height and set inclination angle. Since the present application adjusts the height position and angular position of the second fixture 4 through the adjusting mechanism 6, and further adjusts the distance between the second circuit board 5 and the first circuit board 3 at the solder joint position, the distance adjustment is more accurate, and the change in the solder ball shape is closer to the true shape when the substrate warps and deforms, improving the accuracy of the test of the solder joint shape at different positions and providing a reliable reference for the auxiliary design of the packaging structure.

[0115] The above are only the preferred embodiments of the present utility model. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the technical principle of the present utility model, several improvements and replacements can still be made, and these improvements and replacements should also be regarded as the protection scope of the present utility model.

Claims

1. A testing device, characterized in that: include: A base (1) having a horizontally arranged work surface (11); A first clamp (2) is arranged on the working table (11); A first circuit board (3) is fixed in the first fixture (2); A second clamp (4) is arranged above the first clamp (2) at a distance; A second circuit board (5) is fixed in the second fixture (4) and forms a solder ball installation space (51) for fixing solder balls between the second circuit board and the first circuit board (3); an adjusting mechanism (6) mounted on the work surface (11) and connected to the second fixture (4), the adjusting mechanism (6) being used to adjust the height position and the angle position of the second fixture (4) so ​​as to adjust the distance between the second circuit board (5) and the first circuit board (3) in the vertical direction; and a camera mechanism (7) fixed on the work surface (11) and arranged at a relative interval to the first fixture (2), the camera range of the camera mechanism (7) at least covering the solder ball installation space (51) so as to capture the shape of the solder balls in the solder ball installation space (51).

2. The testing device according to claim 1, characterized in that: The adjustment mechanism (6) comprises a first adjustment component (61) and a second adjustment component (62); the first adjustment component (61) is mounted on the work surface (11); the second adjustment component (62) is movably mounted on the first adjustment component (61); and the second clamp (4) is rotatably mounted on the second adjustment component (62).

3. The testing device according to claim 2, characterized in that: The first adjustment component (61) comprises a first adjustment rod (611), the first adjustment rod (611) is vertically arranged, and the bottom of the first adjustment rod (611) is rotatably assembled on the work surface (11); the first adjustment rod (611) is provided with an external thread, and the second adjustment component (62) is threadedly assembled on the first adjustment rod (611).

4. The testing device according to claim 3, characterized in that: The second adjustment component (62) comprises a mounting portion (621) and a second adjustment rod (622); the mounting portion (621) is threadedly mounted on the first adjustment rod (611); a mounting hole is provided on one side of the mounting portion (621); one end of the second adjustment rod (622) is rotatably mounted in the mounting hole, and the other end is connected to the second clamp (4).

5. The testing device according to claim 1, characterized in that: The first clamp (2) is provided with a first limiting groove (21), the inner cross-sectional shape of the first limiting groove (21) matches the outer edge contour shape of the first circuit board (3), the first circuit board (3) is fixed in the first limiting groove (21) and the soldering pad on the first circuit board (3) is arranged toward the second circuit board (5).

6. The testing device according to claim 5, characterized in that: The outer edge of the first circuit board (3) is bonded and fixed to the inner wall of the first limiting groove (21).

7. The testing device according to claim 1, characterized in that: The second clamp (4) is provided with a second limiting groove (411), the cross-sectional shape of the second limiting groove (411) matches the outer edge contour shape of the second circuit board (5), the second circuit board (5) is fixed in the second limiting groove (411) and the solder pad on the second circuit board (5) is arranged toward the first circuit board (3).

8. The testing device according to claim 7, characterized in that: The second limiting groove (411) penetrates the second clamp (4) along the thickness direction of the second clamp (4).

9. The testing device according to claim 7, characterized in that: The second clamp (4) comprises a plurality of clamping parts (41), the plurality of clamping parts (41) being connected end to end in sequence to enclose and form the second limiting groove (411), and one of the plurality of clamping parts (41) being connected to the adjustment mechanism (6).

10. The testing device according to claim 7, characterized in that: The outer edge of the second circuit board (5) is bonded and fixed to the inner wall of the second limiting groove (411).

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