WO2024082185A1

WO2024082185A1 - Measurement device for package stress of chip, and measurement method

Info

Publication number: WO2024082185A1
Application number: PCT/CN2022/126265
Authority: WO
Inventors: 于子良; 于博轩; 刘昱
Original assignee: 中车工业研究院有限公司
Priority date: 2022-10-19
Filing date: 2022-10-19
Publication date: 2024-04-25

Abstract

A measurement device for the package stress of a chip, and a measurement method. The measurement device for the package stress of a chip comprises a test table (1), a first XYZ-axis movement device (2) mounted on the test table (1), an X-ray measurement device (21) assembled on the first XYZ-axis movement device (2), an upper computer (3), a second XYZ-axis movement device (5) mounted on the test table (1), a distance measurement device (92), and an etching spray head (91). The upper computer (3) controls the X-ray measurement device (21) to measure the stress on the surface of a chip to be subjected to measurement (72); then said chip is transmitted, by means of a transmission component (4), to the etching spray head (91) where said chip (72) is etched; then, an internal stress of said chip is measured by means of the X-ray measurement device (21); and an etching process and a stress measurement process are performed cyclically until stress measurement of all depth gradients is completed. By using the measurement device and the measurement method, the measurement result can be more accurate, the operation time can be reduced, the measurement efficiency can be improved, and the device and method do not increase the difficulty of chip design, and also do not cause the chip itself to be complex.

Description

Chip packaging stress detection device and detection method

Technical Field

The present application relates to the field of chip technology, and in particular to a chip packaging stress detection device and a detection method.

Background technique

Package stress is the internal stress generated when the temperature changes due to the different thermal expansion coefficients and Young's moduli of different packaging materials (chips, copper frames, silver pastes and plastic sealants) inside the semiconductor package. This thermal-mechanical stress can cause delamination inside the semiconductor package and warping of the semiconductor package body. It can also cause the chip inside the semiconductor package to break and the solder joints of the wires to desolder, until the semiconductor device fails. Therefore, the detection and analysis of stress parameters is one of the keys to ensure chip reliability. Detecting stress at various locations on the chip and internal deep stress (including the collection of detailed stress measurement data) helps to understand the reliability of the packaging process, and is also conducive to the improvement of chip manufacturing processes and the analysis of quality problems.

At present, chip packaging stress detection mostly involves pre-installing a piezoresistive sensor module on the chip to be tested. This method increases the structural design burden of the chip to be tested, increases manufacturing costs, and increases the risk of new problems. In addition, when testing stress in the depth direction of the chip to be tested by peeling, inaccurate positioning caused by manual movement will directly affect the accuracy of the test results and reduce the test efficiency.

Summary of the invention

The present application discloses a chip packaging stress detection device and detection method. The detection device and detection method can make the detection result more accurate, reduce the operation time, improve the detection efficiency, and do not increase the burden of chip design, manufacturing cost and the risk of new problems.

The present application discloses a chip package stress detection device. The chip package stress detection device includes a test bench, a first XYZ axis motion device, an X-ray measuring device, a host computer, a second XYZ axis motion device, a distance measuring device and a corrosion nozzle. The test bench includes a conveying component, and the conveying component includes a carrier for carrying a chip to be tested and a chip substrate. The chip substrate is detachably assembled on the carrier and the chip to be tested is located on the chip substrate. The first XYZ axis motion device is installed on the test bench and is assembled with the X-ray measuring device. The host computer controls the movement of the first XYZ axis motion device to adjust the distance between the X-ray measuring device and the chip to be tested; it is also connected to the X-ray measuring device to control the X-ray measuring device to measure the stress on the surface of the chip to be tested. The second XYZ axis motion device is installed on the test bench and is located at both ends of the conveying component with the first XYZ axis motion device, and is assembled with the corrosion nozzle and the distance measuring device. The host computer also controls the carrier of the conveying component to drive the chip substrate and the chip to be tested to move as a whole to the bottom of the etching nozzle, controls the etching nozzle to corrode the chip to be tested, and controls the etching nozzle to corrode the chip to be tested to a preset depth according to the current etching depth measured by the distance measuring device, and controls the corroded chip to be tested and the chip substrate to return, and controls the X-ray measuring device to measure the stress of the test point at the preset depth, and the above-mentioned etching process and the process of measuring stress by the X-ray measuring device are circulated until the stress measurement of all depth gradients is completed. The obtained measurement results are processed to complete the detection of the stress of the chip to be tested.

In some embodiments, the first XYZ axis motion device includes a first Z-direction motion mechanism, and the X-ray measuring device is installed on the first Z-direction motion mechanism and moves in the Z direction under the action of the first Z-direction motion mechanism.

In some embodiments, the second XYZ axis motion device includes a second Z-direction motion mechanism. The etching nozzle is installed on the second Z-direction motion mechanism and moves in the Z direction under the action of the second Z-direction motion mechanism.

In some embodiments, the distance measuring device is provided with a plurality of laser heads. The plurality of laser heads are evenly spaced in a horizontal plane to form a circle. The chip to be measured is located at the center of the circle. The host computer averages the values measured by all the laser heads to obtain the corrosion depth.

In some embodiments, the second XYZ axis motion device includes a second Z-direction motion mechanism, and the distance measuring device is assembled in the second Z-direction motion mechanism and moves only in the XY directions.

In some embodiments, a buffer pad is provided on the chip substrate, and a clamp is installed on the carrier of the test bench; the clamp at least applies a force to the buffer pad to clamp the chip substrate to the test bench.

In some embodiments, the chip substrate is square, including adjacent first sides and adjacent second sides; positioning pieces are respectively arranged on the test bench corresponding to the first sides; and the clamps are pneumatic clamps respectively arranged corresponding to the second sides. The host computer controls the pneumatic clamps to push the chip substrate against the positioning pieces, and then clamps the buffer pad to clamp the chip substrate to the test bench.

In some embodiments, the chip package stress detection device includes a visual recognition device. The visual recognition device is arranged on the second XYZ axis motion device to obtain an image of the corroded chip to be tested. The host computer determines whether the corrosion depth is consistent based on the image and the depth value measured by the distance measuring device. If not, the corrosion nozzle is controlled to continue corrosion until the depth is consistent; if consistent, the corrosion nozzle is controlled to stop corrosion.

In some embodiments, the conveying component includes a guide rail, and the guide rail includes multiple layers. The test bench includes a first lifting platform for carrying the first XYZ-axis motion device and a second lifting platform for carrying the second XYZ-axis motion device. There are at least two sets of the carrier, the chip substrate, and the chip to be tested. The first lifting platform and the second lifting platform each cooperate with the guide rails of the corresponding layer through lifting, so that the carrier, the chip substrate, and the chip to be tested are used as a whole to perform the stress measurement process and the corrosion process in an assembly line manner; or, the guide rail is annular, and there are at least two sets of the carrier, the chip substrate, and the chip to be tested, and the stress measurement process and the corrosion process are performed as a whole in an assembly line manner.

In some embodiments, the chip package stress detection device includes a first communication module and a second communication module. The first communication module is connected to the X-ray measurement device, the first XYZ axis motion device, the transmission component and the host computer. The second communication module is connected to the distance measuring device, the second XYZ axis motion device, the etching nozzle and the host computer.

On the other hand, the present application also discloses a chip package stress detection method, which cooperates with a test device having an X-ray measuring device, an etching nozzle, a distance measuring device and a host computer to perform stress detection on the chip to be tested. The method includes the following steps: the host computer controls the X-ray measuring device to emit X-rays to measure the stress on the surface of the chip to be tested; after completing the surface stress measurement, the host computer controls the etching nozzle to corrode the chip to be tested, and controls the etching nozzle to corrode the chip to be tested to a preset depth according to the current corrosion depth measured by the distance measuring device, controls the X-ray measuring device to measure the stress of the test point at the preset depth, and cycles the above-mentioned corrosion process and the process of measuring stress by the X-ray measuring device until the stress measurement of all depth gradients is completed. The obtained measurement results are processed to complete the detection of the stress of the chip to be tested.

In other embodiments, the detection method includes: obtaining an image of the corroded chip to be tested through visual recognition; the host computer determines whether the corrosion depth is consistent based on the image and the depth value measured by the ranging device, and if not, controls the corrosion nozzle to continue corrosion until the depth is consistent; if consistent, controls the corrosion nozzle to stop corrosion.

In other embodiments, the detection method includes: providing a multi-layer guide rail or a ring guide rail, and the host computer controls the chip to be tested to move in an assembly line manner at the corrosion station and the stress measurement station of the guide rail to realize the measurement process.

As set up as above, the host computer controls the movement of the first XYZ axis motion device, controls the chip to be tested to move between the etching nozzle and the first XYZ axis motion device, etches the chip to be tested by the etching nozzle, and controls the X-ray measuring device to detect the surface and internal stress of the chip to be tested. The entire detection process is completed automatically, which reduces the operation time, improves the detection efficiency, and makes the entire detection process simple to operate and convenient for actual production application; furthermore, the detection device does not use a threshold piezoresistive sensor module, does not add burden to the structural design of the chip to be tested, does not increase the manufacturing cost and the risk of new problems, and does not make the chip to be tested itself complicated; finally, the host computer controls the etching nozzle to erode the chip to be tested and controls the depth of continued etching in combination with the measurement result of the distance measuring device. Compared with the stripping method, the measurement result will not be affected by inaccurate positioning caused by manual movement, and ultimately the stress detection has high accuracy and high detection efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a chip package stress detection device according to an embodiment of the present application;

2 is a schematic diagram showing the connection relationship between the host computer and the first XYZ axis motion device and the X-ray measuring device, and between the host computer and the second XYZ axis motion device, the corrosion nozzle and the distance measuring device according to an embodiment of the present application;

FIG3 is a schematic diagram showing the distribution of laser heads of a distance measuring device according to an embodiment of the present application;

FIG4 is a schematic diagram showing a pneumatic clamp cooperating with a positioning member to clamp a chip substrate according to an embodiment of the present application. For ease of explanation, the chip to be tested is not shown in the figure;

FIG. 5 is a schematic diagram showing another transmission component of a chip package stress detection device according to an embodiment of the present application.

Detailed ways

Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are merely examples of devices consistent with some aspects of the present application as detailed in the appended claims.

The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. Unless otherwise defined, the technical terms or scientific terms used in this application should be understood by people with ordinary skills in the field to which this application belongs. The words "first", "second" and similar words used in the specification and claims of this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate a quantity limit, but indicate that there is at least one. "Multiple" or "several" means two or more. Unless otherwise specified, words such as "front", "rear", "lower" and/or "upper" are only for the convenience of explanation and are not limited to one position or one spatial orientation. Words such as "include" or "comprise" mean that the elements or objects appearing in front of "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, and can include electrical connections, whether direct or indirect. The singular forms "a", "said" and "the" used in this specification and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

Please refer to FIG. 1 , a chip package stress detection device includes a test bench 1, a first XYZ axis motion device 2, an X-ray measuring device 21, a host computer 3, a transmission component 4, a second XYZ axis motion device 5, a distance measuring device 92 and a corrosion nozzle 91. The test bench 1 is used to fix a chip substrate 71 and a chip to be tested 72 located on the chip substrate 71. The chip substrate 71 and the chip to be tested 72 can be fixedly mounted on the test bench 1 through a variety of structures, such as a fixture structure, etc. The test bench 1 also serves as a bearing component for the first XYZ axis motion device 2, the X-ray measuring device 21, the transmission component 4, the second XYZ axis motion device 5, the corrosion nozzle 91 and the distance measuring device 92. In some embodiments, the host computer 3 can also be carried by the test bench 1.

Please continue to refer to FIG. 1 , the first XYZ axis motion device 2 is installed on the test bench 1, and is assembled with the X-ray measuring device 21. The X-ray measuring device 21 adjusts the distance between the X-ray measuring device 21 and the chip to be tested 72 through the first XYZ axis motion device 2, that is, the first XYZ axis motion device 2 can make the X-ray measuring device 21 move in the XYZ direction. Of course, this movement needs to be determined according to the current position between the X-ray measuring device 21 and the chip to be tested 72. For example, when the three directions of XYZ need to be adjusted, the X-ray measuring device 21 moves in the three directions of XYZ respectively to meet the distance requirement between the X-ray measuring device 21 and the chip to be tested 72. When one or two directions in XYZ need to be adjusted, it is only necessary to adjust in the corresponding one or two directions.

Please continue to refer to FIG. 1 and FIG. 2 , the host computer 3 is connected to the X-ray measuring device 21, and controls the X-ray measuring device 21 to measure the stress on the surface of the chip to be tested 72. The X-ray measuring device 21 emits X-rays to the surface of the chip to be tested 72 through an X-ray tube, and measures the stress on the surface of the chip to be tested 72 by measuring the diffraction angle (that is, measuring the stress by X-ray diffraction method). Based on the function of the X-ray measuring device, the structure of the X-ray measuring device 21 is not limited.

The conveying component 4 is assembled on the test bench 1, and is used to convey the chip substrate 71 and the chip to be tested 72 between the first XYZ axis motion device 2 and the second XYZ axis motion device 5, and includes a carrier 41. The function of the carrier 41 is to carry the substrate to be tested 71 and the chip to be tested 72, so that they can move between the first XYZ axis motion device 2 and the second XYZ axis motion device 5, and its structure is not limited. Based on the function of the conveying component 4, the structure of the conveying component 4 is not limited, for example, the conveying component 4 also includes components such as a guide rail 42 or a conveyor belt. The carrier 41 can move on the guide rail 42 or the conveyor belt through components such as rollers to enable the chip to be tested 72 and the chip substrate 71 to move between the first XYZ axis motion device 2 and the second XYZ axis motion device 5. In short, no matter what structure the conveying component 4 adopts, it can realize that the chip to be tested 72 and the chip substrate 71 can move between the first XYZ axis motion device 2 and the second XYZ axis motion device 5 to complete the surface stress measurement and complete the internal stress measurement after being corroded.

Please continue to refer to FIG. 1 , the second XYZ axis motion device 5 is installed on the test bench 1, and is located at both ends of the conveying component 4 with the first XYZ axis motion device 2, and is assembled with the etching nozzle 91 and the distance measuring device 92. The chip substrate 71 and the chip to be tested 72 are moved as a whole between the etching nozzle 91 and the first XYZ axis motion device 2 through the conveying component 4, and the specific movement process is described in detail in the working process of the chip stress packaging detection device.

Please continue to refer to FIG. 1 , and the working process of the chip packaging stress detection device is described as follows:

Measuring the stress on the surface of the chip to be tested 72: After the chip to be tested 72 and the chip substrate 71 are fixed to the carrier 41 of the test bench 1, the position between the X-ray measuring device 21 and the chip to be tested 72 is adjusted. The host computer 3 controls the first XYZ axis motion device 2 to move according to the position information of the point to be measured on the surface of the chip to be tested 72 to achieve the position adjustment, so as to ensure that the X-rays emitted by the X-ray measuring device 21 can irradiate the point to be tested. After the position is adjusted, the X-ray measuring device 21 is controlled to emit X-rays to the point to be tested on the surface of the chip to be tested 72 to obtain diffraction angle data (for example, the change value of the diffraction angle), etc. The stress value of the surface of the chip to be tested 72 is obtained through these data, and the stress measurement of the surface of the chip to be tested 72 is completed.

Measuring the internal stress of the chip to be tested 72: After measuring the stress of the surface of the chip to be tested 72, the host computer 3 controls the conveying component 4 to convey the chip substrate 71 and the chip to be tested 72 to the bottom of the etching nozzle 91 through the carrier 41, and then controls the etching nozzle 91 to corrode the chip to be tested 72, and controls the etching nozzle 91 to corrode the chip to be tested 72 to a preset depth according to the current corrosion depth measured by the distance measuring device 92. The preset depth is set according to actual needs. After corrosion to the preset depth, the host computer 3 controls the conveying component 4 so that the carrier 41 returns the chip substrate 71 and the corroded chip to be tested 72 to the first XYZ axis motion device 2. Of course, if necessary, the host computer 3 will control the first XYZ axis motion device 2 to move to adjust the positional relationship between the X-ray measuring device 21 and the corroded chip to be tested 72. The host computer 3 then controls the X-ray measuring device 21 to measure the stress of the test point at the preset depth, and cycles the above-mentioned corrosion process and the process of measuring stress by the X-ray measuring device 21 (here, the "cycle" only refers to the cycle of this process, and the parameters such as the depth of the chip 72 to be tested are still set according to the needs) until the stress measurement of all depth gradients is completed. The obtained measurement results are processed to complete the stress detection of the chip to be tested. There are two ways to obtain the results of this processing: 1) After the surface stress and internal stress are measured, these results are processed centrally to complete the stress detection; 2) After the surface stress is completed, the surface stress detection is completed by processing the results, and after the internal stress measurement is completed, the internal stress detection is completed by processing the results.

As described above, the host computer 3 controls the movement of the first XYZ axis motion device 2, and controls the chip to be tested 72 to move between the etching nozzle 91 and the first XYZ axis motion device 2, and the etching nozzle 91 is used to etch the chip to be tested 72, and the X-ray measuring device 21 is controlled to measure the surface and internal stress of the chip to be tested 72, and the obtained measurement results are processed to complete the detection of the stress of the chip to be tested. The entire detection process is completed automatically, which reduces the operation time, improves the detection efficiency, and makes the entire detection process simple to operate and convenient for actual production application; furthermore, the detection device does not use the threshold piezoresistive sensor module, which will not add burden to the structural design of the chip to be tested, nor will it make the chip to be tested itself complicated, and will not increase the manufacturing cost and the risk of new problems; finally, the host computer 3 controls the etching nozzle 91 to etch the chip to be tested 72 and controls the depth of continued etching in combination with the measurement result of the distance measuring device 92. Compared with the stripping method, the detection result will not be affected by inaccurate positioning caused by manual movement, and finally the stress detection is accurate and efficient.

Please continue to refer to FIG. 1. In some embodiments, the first XYZ axis motion device 2 includes a first Z-direction motion mechanism 22, and the X-ray measuring device 21 is installed on the first Z-direction motion mechanism 22, and moves in the Z direction under the action of the first Z-direction motion mechanism 22. In the embodiment of the present application, the first XYZ axis motion device 2 includes a first X-direction motion mechanism 23 and a first Y-direction motion mechanism 24. Under the control of the host computer 3, the first X-direction motion mechanism 23, the first Z-direction motion mechanism 22 and the X-ray measuring device 21 as a whole can move in the Y direction under the action of the first Y-direction motion mechanism 24; the first Z-direction motion mechanism 22 and the X-ray measuring device 21 as a whole move in the X direction under the action of the first X-direction motion mechanism 23; the X-ray measuring device 21 moves in the Z direction under the action of the first Z-direction motion mechanism 22, and the position adjustment of the X-ray measuring device 21 in the XYZ direction is realized through the above control. Therefore, based on the action of the first XYZ axis motion device 2, its structure is not limited, and it is sufficient to realize the position adjustment of the X-ray measuring device 21 in the XYZ direction. In the implementation manner of the present application, the first Z-axis motion mechanism 22, the first X-axis motion mechanism 23 and the first Y-axis motion mechanism 24 are all guide rail and slider structures, all composed of linear guides and linear servo motors, and equipped with guide rail clamps for braking control. The strokes of the first X-axis motion mechanism 23 and the first Y-axis motion mechanism 24 are 300mm, and the stroke of the first Z-axis motion mechanism 22 is 200mm, and the positioning accuracy of each is 0.01mm. The first Y-axis motion mechanism 24 has two sets, which are respectively installed on the pillars on both sides. The first X-axis motion mechanism 23 has one set, which is installed on the first Y-axis motion mechanism 24. The first Z-axis motion mechanism 22 has a set of slider guide rail mechanisms, which are installed on the first X-axis motion mechanism 23.

As set up above, since the X-ray measuring device 21 is installed on the first Z-direction motion mechanism 22, it moves in the Z-direction under the action of the first Z-direction motion mechanism 22. In this way, the X-ray measuring device 21 can emit X-rays from top to bottom, so that the X-rays irradiate the chip to be tested 72, which is more convenient for X-rays to irradiate the test point. At the same time, because the X-ray measuring device 21 moves in the Z-direction, compared with the X-ray measuring device 21 being set in the X-direction or the Y-direction, the structure of the first XYZ-axis motion device 2 is simpler.

Please continue to refer to FIG. 1. In some embodiments, the second XYZ-axis motion device 5 includes a second Z-direction motion mechanism 51, a second X-direction motion mechanism 53, and a second Y-direction motion mechanism 54, wherein the second X-direction motion mechanism 53 is installed on the second Y-direction motion mechanism 54. The second Z-direction motion mechanism 51 is installed on the second X-direction motion mechanism 53. The corrosion nozzle 91 is installed on the second Z-direction motion mechanism 51, and moves in the Z direction under the action of the second Z-direction motion mechanism 51. In the embodiment of the present application, the structure of the second XYZ-axis motion device 5 can be the same as that of the first XYZ-axis motion device 2, or it can be different, as long as the position adjustment of the corrosion nozzle 91 in the XYZ direction can be achieved.

As set up above, since the etching nozzle 91 is installed on the second Z-axis motion mechanism 51, it is easier for the etching nozzle 91 to spray the etching liquid to corrode the chip to be tested 72. At the same time, because the etching nozzle 91 moves in the Z direction, compared with the etching nozzle 91 set in the X direction or the Y direction, the structure of the second XYZ axis motion device 5 is simpler.

Please refer to FIG. 3 and FIG. 1 . In some embodiments, the distance measuring device 92 is provided with a plurality of laser heads 921. The plurality of laser heads 921 are evenly spaced in a horizontal plane to form a circle, and the chip to be measured 72 is located at the center of the circle. The host computer averages the values measured by all the laser heads to obtain the depth of corrosion. FIG. 3 schematically shows five laser heads 921, which form a circle.

As set up above, since the upper computer 3 averages the values measured by all the laser heads 921 to obtain the depth of corrosion, the measurement error caused by the uneven corrosion surface is corrected as much as possible by taking the average value, thereby improving the accuracy of corrosion and not affecting the measurement results due to inaccurate positioning caused by manual movement, ultimately making the stress measurement more accurate, for example, the depth of corrosion is consistent.

Please continue to refer to FIG. 1 . In some embodiments, the second XYZ axis motion device 5 includes a second Z-direction motion mechanism 51 . The distance measuring device 92 is assembled in the second Z-direction motion mechanism 51 and moves only in the XY directions.

As set up as above, since the distance measuring device 92 only moves in the XY direction and is installed on the second Z-direction motion mechanism 51, the distance measuring device 92 can be adjusted to any position above the chip to be measured 72 by moving in the XY direction, which makes it easier for the distance measuring device 92 assembled in the second Z-direction motion mechanism 51 to measure the depth. Furthermore, the distance measuring device 92 assembled in the second Z-direction motion mechanism 51 also makes it easier for the distance measuring device 92 to measure the corroded chip to be measured 72, and the measurement accuracy is high. For example, when the distance measuring device 92 is a laser distance measuring device, the laser emitted by the distance measuring device 92 irradiates the corroded part of the chip to be measured 72 from top to bottom, thereby achieving high accuracy.

Please continue to refer to FIG. 1. In some embodiments, a buffer pad 73 is provided on the chip substrate 71, and a clamp 43 is installed on the carrier 41 of the test bench 1. The clamp 43 at least applies a force to the buffer pad 73 to clamp the chip substrate 71 to the test bench 1. The at least applying a force to the buffer pad 73 includes the following two situations according to the different structures of the clamp 43: 1) The clamp 43 includes an upper arm and a lower arm, the upper arm contacts the buffer pad 73, and the lower arm contacts the test bench 1, and the upper arm and the lower arm clamp the buffer pad 73, the chip substrate 71 and the corresponding part on the test bench 1; 2) The clamp 43 includes a supporting arm, the buffer pad 73 is provided on the test bench 1, and the supporting arm presses the buffer pad 73 against the test bench 1, thereby clamping the chip substrate 71 to the test bench 1.

As described above, due to the provision of the buffer pad 73, the buffer pad 73 can buffer and release the clamping force generated by the fixture 43, thereby preventing the clamping force from affecting the detection result and damaging the chip substrate 71. Based on the role of the buffer pad 73, the technicians can understand that the material of the buffer pad 73 is any material that can play a buffering role, for example, the buffer pad 73 is a rubber pad or a sponge pad.

Please refer to FIG. 4 and FIG. 1 . In some embodiments, the chip substrate 71 is square and includes adjacent first sides 711 and adjacent second sides 712. The carrier 41 of the test bench 1 is provided with positioning members 44 corresponding to the first sides 711. The clamp 43 is a pneumatic clamp respectively provided on the second sides 712. The host computer 3 controls the pneumatic clamp to push the chip substrate 71 against the positioning member 44, and then clamps the buffer pad 73, thereby clamping the chip substrate 71 to the test bench 1.

As described above, since the positioning member 44 is provided and the clamp 43 is a pneumatic clamp, the upper computer 3 controls the pneumatic clamp to push the chip substrate 71 to achieve positioning and then clamp the chip substrate 71. The whole process is automated, which reduces the operation time and improves the test efficiency. The chip substrate 71 is firmly clamped, which also helps to improve the accuracy of the test. In addition, the automatic clamping by the clamp 43 can ensure the consistency of the clamping, which is also conducive to improving the accuracy of the test.

Please continue to refer to FIG. 1. In some embodiments, the chip package stress detection device further includes a visual recognition device. The visual recognition device is disposed on the second XYZ axis motion device to obtain an image of the corroded chip to be tested. The host computer determines whether the corrosion depth is consistent based on the image and the depth value measured by the distance measuring device. If not, the corrosion nozzle is controlled to continue to etch until the depth is consistent; if consistent, the corrosion nozzle is controlled to stop etching.

As described above, the visual recognition device can determine the situation of the corrosion area, and the distance measuring device 92 can obtain the depth of a certain point in the corrosion area. Therefore, the combination of the visual recognition device and the distance measuring device 92 realizes the combination of point and surface, and then, it can be known whether the depth of corrosion in the corrosion area is consistent. Compared with the method without using the visual recognition device, the number of times the distance measuring device 92 is adjusted can be reduced, and the test efficiency and test accuracy can be improved. Because when the visual recognition device is not used, the position of the distance measuring device 92 needs to be adjusted multiple times to obtain multiple depth values in the corrosion area, and then, the relationship between the multiple depth values is used to determine whether the corrosion depth is consistent.

Please refer to FIG5 . In some embodiments, the guide rail 42 of the conveying component 4 includes multiple layers. In FIG5 , the guide rail 42 includes an upper guide rail 421 and a lower guide rail 422 that are stacked, that is, only two layers of guide rails are illustrated. The test bench 1 includes a first lifting platform 11 that carries the first XYZ-axis motion device 2 and a second lifting platform 12 that carries the second XYZ-axis motion device 5. There are at least two sets of the carrier 41 , the chip substrate 71 , and the chip to be tested 72 . The first lifting platform 11 and the second lifting platform 12 each cooperate with the guide rails of the corresponding layer by lifting, so that the carrier 41 , the chip substrate 71 , and the chip to be tested 72 as a whole can perform the stress testing process and the corrosion process in an assembly line manner.

Taking the guide rail with only two layers as an example, the above process is described as follows in conjunction with FIG5: After the surface stress measurement of the first chip to be tested 72 is completed at the highest position of the first lifting platform 11 (the first lifting platform 11 is indicated by a dotted line frame in FIG5 to be at the highest position, and the first lifting platform 11 is indicated by a solid line frame to be at the lowest position), the first lifting platform 11 descends so that the carrier 41, the chip substrate 71 and the first chip to be tested 72 can be transferred to the second lifting platform 12 by the lower guide rail 422. The etching of the chip to be tested 72 can be performed when the second lifting platform 12 is at the lowest position or the highest position (the second lifting platform 12 is indicated by a dotted line frame in FIG5 to be at the highest position, and the second lifting platform is indicated by a solid line frame to be at the lowest position). After the etching is completed, the first chip to be tested 72 returns to the first lifting platform 11 through the upper guide rail 421, and the cycle is repeated. In the above process, after the first chip to be tested 72 is transported away from the first lifting platform 11, the first lifting platform 11 rises and can place the second chip to be tested 72 to measure the surface stress of the second chip to be tested 72. After the surface stress is measured, it is transported to the second lifting platform 12 for corrosion. This cycle allows the chip to be tested 72 to perform stress measurement in an assembly line manner.

Of course, as an alternative to the above embodiment, the guide rail 42 may also be ring-shaped, and there are at least two sets of the carrier 41, the chip substrate 71 and the chip to be tested 72, and the stress measurement process and the corrosion process are performed in an assembly line manner as a whole.

As set up as above, by adopting the assembly line method, two or more stations can work simultaneously, thereby improving the overall test efficiency and reducing the production cycle. Moreover, by setting the guide rail to be multi-layer or ring-shaped, the structure of the chip packaging stress detection device is also simple.

Please refer to FIG. 2 , the chip package stress detection device includes a first communication module 31 and a second communication module 32. The first communication module 31 is connected to the X-ray measuring device 21, the first XYZ axis motion device 2, the transmission component 4 and the host computer 3, so that the host computer 3 can control the X-ray measuring device 21, the first XYZ axis motion device 2 and the transmission component 4 through the first communication module 31. The second communication module 32 is connected to the distance measuring device 92, the second XYZ axis motion device 5, the corrosion nozzle 91 and the host computer 3, so that the host computer 3 controls the distance measuring device 92, the second XYZ axis motion device 5 and the corrosion nozzle 91 through the second communication module 32. In some embodiments, the first communication module 31 and the second communication module 32 can be a module.

As described above, since the first communication module 31 and the second communication module 32 are provided, and the host computer 3 controls the corresponding components through the first communication module 31 and the second communication module 32, it is convenient to wire to realize the connection between the distance measuring device 92 and the host computer 3.

Based on the technical inspiration of the working process of the above detection device, the present application also discloses a chip packaging stress detection method, which uses a test device with an X-ray measurement device, an etching nozzle, a distance measuring device and a host computer to perform stress detection on the chip to be tested. The method includes the following steps:

Controlling the X-ray measuring device to emit X-rays by the host computer to measure stress on the surface of the chip to be tested;

After completing the surface stress measurement, the host computer also controls the etching nozzle to corrode the chip to be tested, and controls the etching nozzle to corrode the chip to be tested to a preset depth according to the current etching depth measured by the distance measuring device, controls the X-ray measuring device to measure the stress of the test point at the preset depth, and repeats the above etching process and the process of measuring stress by the X-ray measuring device until the stress measurement of all depth gradients is completed, and processes the obtained measurement results to complete the detection of the stress of the chip to be tested.

The implementation process of the above method can refer to the description of the above detection device part. Its beneficial effects are the same as the beneficial effects of the above detection device and will not be repeated here.

In some embodiments, the detection method includes: obtaining an image of the corroded chip to be tested through visual recognition; the host computer determines whether the corrosion depth is consistent based on the image and the depth value measured by the ranging device, and if not, controls the corrosion nozzle to continue corrosion until the depth is consistent; if consistent, controls the corrosion nozzle to stop corrosion, and its beneficial effects are the same as those of the aforementioned detection device and will not be repeated.

In other embodiments, the detection method includes: setting up a multi-layer guide rail or a ring guide rail, and the host computer controls the chip to be tested to move in an assembly line manner at the corrosion station and the stress testing station of the guide rail to realize the measurement process. Its beneficial effects are the same as those of the aforementioned detection device and will not be repeated.

In the present application, the structural embodiments and method embodiments may complement each other if they do not conflict.

The above is only a preferred implementation mode of the present application, and does not constitute any form of limitation to the present application. Although the present application has been disclosed as a preferred implementation mode as above, it is not used to limit the present application. Any technician familiar with this profession can make some changes or modify the technical contents disclosed above into equivalent implementation modes without departing from the scope of the technical solution of the present application. However, any simple modification, equivalent change and modification made to the above implementation modes based on the technical essence of the present application without departing from the content of the technical solution of the present application still fall within the scope of the technical solution of the present application.

Claims

A chip packaging stress detection device, characterized in that it includes a test bench, a first XYZ axis motion device, an X-ray measurement device, a host computer, a second XYZ axis motion device, a distance measuring device and an etching nozzle:

The test bench comprises a conveying component, wherein the conveying component comprises a carrier for carrying a chip to be tested and a chip substrate, wherein the chip substrate is detachably assembled on the carrier and the chip to be tested is located on the chip substrate;

The first XYZ axis motion device is installed on the test bench and is assembled with the X-ray measurement device;

The host computer controls the movement of the first XYZ axis motion device to adjust the distance between the X-ray measuring device and the chip to be tested; and is also connected to the X-ray measuring device to control the X-ray measuring device to measure the stress on the surface of the chip to be tested;

The second XYZ axis motion device is installed on the test bench, and is located at both ends of the conveying component together with the first XYZ axis motion device, and is assembled with the corrosion nozzle and the distance measuring device;

The host computer also controls the carrier of the conveying component to drive the chip substrate and the chip to be tested to move as a whole to the bottom of the etching nozzle, controls the etching nozzle to corrode the chip to be tested, and controls the etching nozzle to corrode the chip to be tested to a preset depth according to the current etching depth measured by the distance measuring device, and controls the corroded chip to be tested and the chip substrate to return to their positions, and controls the X-ray measuring device to measure the stress of the test point at the preset depth, and repeats the above-mentioned etching process and the process of measuring stress by the X-ray measurement until the stress measurement of all depth gradients is completed; and processes the obtained measurement results to complete the detection of the stress of the chip to be tested.
The chip package stress detection device according to claim 1 is characterized in that the first XYZ axis motion device includes a first Z-direction motion mechanism, and the X-ray measuring device is installed on the first Z-direction motion mechanism and moves in the Z direction under the action of the first Z-direction motion mechanism.
The chip package stress detection device according to claim 1 is characterized in that the second XYZ axis motion device includes a second Z-direction motion mechanism, and the corrosion nozzle is installed on the second Z-direction motion mechanism and moves in the Z direction under the action of the second Z-direction motion mechanism.
The chip package stress detection device according to claim 1 is characterized in that the distance measuring device is provided with a plurality of laser heads, and the plurality of laser heads are evenly spaced in a horizontal plane to form a circle, the chip to be tested is located at the center of the circle, and the host computer averages the values measured by all the laser heads to obtain the corrosion depth.
The chip package stress detection device according to claim 1 or 4 is characterized in that the second XYZ axis motion device includes a second Z-direction motion mechanism, and the distance measuring device is assembled in the second Z-direction motion mechanism and moves only in the XY direction.
The chip package stress detection device according to claim 1 is characterized in that a buffer pad is provided on the chip substrate, and a clamp is installed on the carrier of the test bench; the clamp at least applies a force to the buffer pad to clamp the chip substrate to the test bench.
The chip package stress detection device according to claim 6 is characterized in that the chip substrate is square, including adjacent first sides and adjacent second sides; positioning members are respectively arranged on the test bench corresponding to the first sides; and the clamp is a pneumatic clamping jaw respectively arranged corresponding to the second sides;

The host computer controls the pneumatic clamp to push the chip substrate against the positioning member, and then clamps the buffer pad to clamp the chip substrate to the test bench.
The chip package stress detection device according to claim 1 is characterized in that the chip package stress detection device comprises a visual recognition device, which is arranged on the second XYZ axis motion device to obtain an image of the corroded chip to be tested;

The host computer determines whether the corrosion depth is consistent according to the image and the depth value measured by the distance measuring device. If not, the upper computer controls the corrosion nozzle to continue corrosion until the depth is consistent; if consistent, the upper computer controls the corrosion nozzle to stop corrosion.
The chip package stress detection device according to claim 1 is characterized in that the conveying component includes a guide rail, and the guide rail includes multiple layers; the test bench includes a first lifting platform for carrying the first XYZ axis motion device and a second lifting platform for carrying the second XYZ axis motion device; the carrier, the chip substrate and the chip to be tested each have at least two sets; the first lifting platform and the second lifting platform each cooperate with the guide rail of the corresponding layer through lifting, so that the carrier, the chip substrate and the chip to be tested as a whole perform the stress measurement process and the corrosion process in an assembly line manner;

Alternatively, the guide rail is ring-shaped, and there are at least two sets of the carrier, the chip substrate and the chip to be tested, and the stress measurement process and the corrosion process are performed in an assembly line manner as a whole.
The chip package stress detection device according to claim 1, characterized in that the chip package stress detection device comprises a first communication module and a second communication module;

The first communication module is connected to the X-ray measuring device, the first XYZ axis motion device, the transmission component and the host computer;

The second communication module is connected to the distance measuring device, the second XYZ axis motion device, the corrosion nozzle and the host computer.
A chip packaging stress detection method, which performs stress detection on a chip to be tested by using a test device having an X-ray measuring device, an etching nozzle, a distance measuring device and a host computer, is characterized in that the method comprises the following steps:

The host computer controls the X-ray measuring device to emit X-rays to measure the stress on the surface of the chip to be tested;

After completing the surface stress measurement, the host computer also controls the etching nozzle to corrode the chip to be tested, and controls the etching nozzle to corrode the chip to be tested to a preset depth according to the current etching depth measured by the distance measuring device, controls the X-ray measuring device to measure the stress of the test point at the preset depth, and repeats the above etching process and the process of measuring stress by the X-ray measuring device until the stress measurement of all depth gradients is completed; and processes the obtained measurement results to complete the detection of the stress of the chip to be tested.
The chip package stress detection method according to claim 11, characterized in that the detection method comprises: obtaining an image of the corroded chip to be tested by visual recognition;

The host computer determines whether the corrosion depth is consistent according to the image and the depth value measured by the distance measuring device. If not, the upper computer controls the corrosion nozzle to continue corrosion until the depth is consistent; if consistent, the upper computer controls the corrosion nozzle to stop corrosion.
The chip package stress detection method according to claim 11 is characterized in that the detection method includes: setting a multi-layer guide rail or a ring guide rail, and the host computer controls the chip to be tested to move in a pipeline manner at the corrosion station and the stress test station of the guide rail to realize the measurement process.