Microelectronic medium sheet inspection method, device, electronic device, and storage medium

Abstract

This invention discloses a method, apparatus, electronic device, and storage medium for detecting microelectronic dielectric substrates. The method includes performing the following detection steps on the detection area of ​​the dielectric substrate under test: heating a first surface of the current detection area located at a preset heating station; the heat is conducted through a first surface conductive layer on the first surface and an inner wall conductive layer on the inner wall of the via to a second surface conductive layer on the second surface, and continues to be conducted on the second surface conductive layer; before the heating control parameters reach the overheating parameter, driving the current detection area to the detection station; acquiring a first thermal image of the second surface of the current detection area located at the detection station; and determining whether there is an anomaly in the dielectric substrate under test based on the actual heat distribution of the heat conduction area around the center of the via in the first thermal image. This method enables high-precision, high-efficiency, and non-destructive detection of dielectric substrate anomalies, is unaffected by heat sources, and facilitates streamlined operations.

Description

Technical Field

[0001] This invention relates to the field of microelectronic packaging technology, specifically to a method, apparatus, electronic device, storage medium, and computer program product for testing microelectronic dielectric substrates. Background Technology

[0002] Microelectronic packaging refers to a technology that protects integrated circuit (IC) chips or other microelectronic components and provides connectivity to external circuits. Microelectronic packaging is a crucial step in semiconductor manufacturing. Currently, integrated circuit packaging structures have evolved from traditional planar structures to 2.5D / 3D and even heterogeneous integration packaging. In high-end electronics manufacturing, 2.5D and 3D packaging based on through-silicon vias (TSVs) and through-glass vias (TGVs) are key technologies for improving the performance of electronic devices. TSVs and TGVs connect multiple layers / chips, typically using thermally conductive materials like copper as the conductive medium. This allows for effective improvement in system integration and performance at a lower cost, and has significant future development potential.

[0003] Currently, after packaging, besides direct observation through sample destruction and cutting, there are two main types of detection methods suitable for the characteristics of TSV / TGV: contact and non-contact. Contact detection methods generally include electrical testing, boundary scanning, and functional testing, which can detect chip failures and indirectly determine whether there are abnormalities in the substrate. Non-contact detection technologies can obtain the microscopic characteristics of the chip without damaging it and provide good process control information. The main non-contact detection methods include electrical testing, optical inspection, and X-ray inspection. Existing testing methods all test the performance of the packaged product after packaging, which not only has a time lag and wastes costs, but also makes defect detection difficult and inaccurate. Summary of the Invention

[0004] The present invention was proposed in view of the above-mentioned problems. Embodiments of the present invention disclose a method for detecting microelectronic dielectric substrates, a device for detecting microelectronic dielectric substrates, an electronic device, a storage medium, and a computer program product.

[0005] According to one aspect of the present invention, a method for inspecting a microelectronic dielectric substrate is provided. A via is formed on the dielectric substrate. The method includes performing the following inspection steps on the inspection area of ​​the dielectric substrate under test: heating a first surface of the current inspection area located at a preset heating station, wherein, within the current inspection area, heat can be conducted through a first surface conductive layer on the first surface and an inner wall conductive layer on the inner wall of the via to a second surface conductive layer on the second surface, and continue to be conducted on the second surface conductive layer; driving the current inspection area to the inspection station before the heating control parameter reaches an overheating parameter, wherein the overheating parameter refers to the heating control parameter that causes the inspection area of ​​a normal dielectric substrate to reach an overheated state when heated; acquiring a first thermal image of the second surface of the current inspection area located at the inspection station; and determining whether there is an abnormality in the dielectric substrate under test based on the actual heat distribution of the heat conduction area around the center of the via in the first thermal image, wherein the heat conduction area is the conductive area on the second surface conductive layer surrounding the via area.

[0006] For example, before the heating control parameters reach the overheating heating parameters, driving the current detection area to the detection station includes: heating the current detection area and waiting until the heating control parameters reach the first preset heating parameters before driving the current detection area to the detection station; wherein, the first preset heating parameters refer to the heating control parameters that enable the heat distribution in the heat conduction area around the via center in the second thermal image acquired from the second surface of the detection area facing the normal dielectric plate to meet the corresponding target heat distribution requirements when the first surface of the detection area of ​​the normal dielectric plate is heated.

[0007] For example, determining whether the dielectric substrate under test is abnormal based on the actual heat distribution of the heat conduction area around the via center in the first thermal image includes: determining whether the dielectric substrate under test is abnormal based on the actual heat distribution in the heat conduction area in the first thermal image and the first standard heat distribution; wherein, the first standard heat distribution refers to the heat distribution in the heat conduction area in the second thermal image acquired when the detection area of ​​a normal dielectric substrate is heated to the first preset heating parameter.

[0008] For example, the heat conduction regions corresponding to two adjacent vias on the dielectric substrate under test are independent of each other.

[0009] For example, the detection step further includes: before the heating control parameter reaches the overheating parameter and during the heating of the current detection area, acquiring a first thermal image of the second surface of the current detection area located at the preset heating station; and determining whether there is an internal abnormality in the test medium plate based on the actual heat distribution of the via area around the via center in the first thermal image of the via taken towards the preset heating station.

[0010] For example, driving the current detection area to the detection station includes: first determining, based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station, that there is no abnormality inside the via in the medium board under test, and then driving the current detection area to the detection station.

[0011] For example, before the heating control parameters reach the overheating heating parameters and during the heating of the current detection area, a first thermal image is captured towards the second surface of the current detection area located at a preset heating station. This includes: while heating the current detection area and waiting until the heating control parameters reach the second preset heating parameters, a first thermal image is captured towards the preset heating station. The second preset heating parameters refer to the heating parameters that, when heating the first surface of the detection area of ​​the normal dielectric plate, enable the heat distribution within the via area around the via center in the second thermal image captured towards the second surface of the detection area of ​​the normal dielectric plate to meet the corresponding target heat distribution requirements.

[0012] For example, determining whether there is an internal anomaly in the dielectric substrate under test based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station includes: determining whether there is an internal anomaly in the dielectric substrate under test based on the actual heat distribution in the via area in the first thermal image taken towards the preset heating station and the second standard heat distribution; wherein, the second standard heat distribution refers to the heat distribution of the via area in the second thermal image collected when a normal dielectric substrate is heated to the second preset heating parameter.

[0013] For example, the method further includes the following heating calibration step for calibrating heating control parameters: heating the first surface of the detection area of ​​the normal dielectric plate, wherein heat can be conducted through the first surface conductive layer of the first surface of the normal dielectric plate and the inner wall conductive layer on the inner wall of the via on the normal dielectric plate to the second surface conductive layer of the second surface of the normal dielectric plate, and continue to be conducted on the second surface conductive layer of the normal dielectric plate; before the heating control parameters reach the overheating heating parameters, acquiring a second thermal image of the second surface of the detection area of ​​the normal dielectric plate; determining whether the target thermal distribution requirements are met based on the thermal distribution of the target area in the second thermal image, and calibrating the heating control parameters when the target thermal distribution requirements are met as preset heating parameters corresponding to the target thermal distribution requirements, wherein the target area includes the via area and / or the thermal conduction area.

[0014] For example, the substrate under test has multiple sets of vias, and the area where each set of vias is located is used as the current detection area to perform the detection steps.

[0015] According to another aspect of the present invention, a microelectronic dielectric substrate testing device is also provided, wherein a via is formed on the dielectric substrate, comprising: a testing module, the testing module being used to perform testing steps on the testing area of ​​the dielectric substrate under test, the testing module comprising: a heating submodule, used to heat a first surface of the current testing area located at a preset heating station, wherein, within the current testing area, heat can be conducted through a first surface conductive layer of the first surface and an inner wall conductive layer on the inner wall of the via to a second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer; a driving submodule, used to drive the current testing area to the testing station before the heating control parameter reaches the overheating heating parameter, the overheating heating parameter referring to the heating control parameter that causes the testing area of ​​a normal dielectric substrate to reach an overheated state when heating a normal dielectric substrate; an acquisition submodule, used to acquire a first thermal image of the second surface of the current testing area located at the testing station; and a determination submodule, used to determine whether there is an abnormality in the dielectric substrate under test based on the actual heat distribution of the heat conduction area around the center of the via in the first thermal image, the heat conduction area being the conductive area on the second surface conductive layer surrounding the via area.

[0016] According to another aspect of the present invention, an electronic device is also provided, comprising: a processor and a memory, wherein the memory stores computer program instructions, which are executed by the processor to perform the microelectronic substrate detection method described above.

[0017] According to another aspect of the present invention, a storage medium is also provided, on which program instructions are stored, which are used to execute the above-described microelectronic substrate detection method when running.

[0018] According to another aspect of the present invention, a computer program product is also provided, including computer program instructions, which, when executed, are used to perform the microelectronic substrate detection method as described above.

[0019] The aforementioned technical solution heats one surface of the current detection area of ​​the dielectric substrate under test when the current detection area is located at a preset heating station. Then, the current detection area is moved to the detection station, and the actual heat distribution within the heat conduction area around the via center is detected on the other surface to determine any anomalies in the dielectric substrate. This solution achieves high-precision, high-efficiency, and non-destructive detection of dielectric substrate anomalies, and can detect anomalies in both the internal and / or external conductive layers of the vias, providing comprehensive detection. Furthermore, when determining anomalies by observing the heat distribution within the heat conduction area around the via center, directly acquiring thermal images at the preset heating station can affect the accuracy of the assessment due to the combined effects of heat conduction from the metal conductive layer and heat emitted by the heat source itself. Acquiring thermal images at the detection station avoids the influence of the heat source itself, improving the accuracy of the assessment and further enhancing the accuracy of anomaly detection. In addition, the above solution performs heating and thermal image acquisition at different workstations, which can facilitate streamlined operations. For example, when the current detection area is heated and moved to the detection workstation for image acquisition, the next detection area of ​​the current test medium board or any detection area of ​​another test medium board can be moved to the preset heating workstation for heating, and so on in a cyclical manner.

[0020] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0021] The above and other objects, features, and advantages of the present invention will become more apparent from the more detailed description of the embodiments of the invention in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same parts or steps.

[0022] Figure 1 A flowchart illustrating the detection steps in a microelectronic dielectric substrate detection method according to an embodiment of the present invention is shown.

[0023] Figure 2 A schematic diagram illustrating heating a dielectric substrate and acquiring an image according to an embodiment of the present invention is shown;

[0024] Figure 3 A schematic diagram of the via region and the heat conduction region according to an embodiment of the present invention is shown;

[0025] Figure 4 A schematic diagram showing the temperature distribution curve corresponding to any via according to an embodiment of the present invention;

[0026] Figure 5 A schematic diagram showing the temperature distribution curve corresponding to any via according to another embodiment of the present invention;

[0027] Figure 6 A schematic block diagram of a microelectronic substrate testing apparatus according to an embodiment of the present invention is shown; and

[0028] Figure 7 A schematic block diagram of an electronic device according to an embodiment of the present invention is shown. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of the present invention, and not all of the embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of the present invention.

[0030] As described above, to at least partially solve the technical problems of traditional detection methods, embodiments of the present invention provide a microelectronic dielectric substrate detection method. This method involves heating the current detection area of ​​the dielectric substrate under test at a preset heating station, and then acquiring a thermal image of the current detection area after moving the current heating station to the detection station. The presence of anomalies in the dielectric substrate is determined based on the heat distribution of the heat conduction area around the via center in the thermal image. This approach achieves high-precision, high-efficiency, and non-destructive detection of dielectric substrate anomalies, is unaffected by heat sources, and facilitates streamlined operations. The microelectronic dielectric substrate detection method includes performing a detection step on the detection area of ​​the dielectric substrate under test. Vias are formed on the dielectric substrate. The detection area can be any size area on the dielectric substrate, and may include one or more vias. For example, the detection area can be the entire area of ​​the dielectric substrate or a portion of the dielectric substrate. Figure 1 A flowchart illustrating the detection steps in a microelectronic dielectric substrate detection method according to an embodiment of the present invention is shown. Figure 1 As shown, the detection steps include steps S110, S120, S130 and S140.

[0031] In step S110, the first surface of the current detection area located at the preset heating station is heated. In the current detection area, heat can be conducted through the first surface conductive layer of the first surface and the inner wall conductive layer on the inner wall of the via to the second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer.

[0032] The microelectronic substrate inspection method can be executed by a processor in a microelectronic substrate inspection system. Exemplarily, the microelectronic substrate inspection system may further include a transport module on which substrates (including substrates under test and normal substrates described herein) can be placed. The processor can be communicatively connected to the transport module and can be used to control the operation of the transport module to move the substrate between various stations or to move different inspection areas of the substrate to a station. For example, during step S110, the current inspection area of ​​the substrate under test can be moved to a preset heating station via the transport module. The current inspection area is the currently inspected area on the substrate under test. Exemplarily, the size of each inspection area of ​​the substrate under test can be set at least according to the heating range of the heating device and / or a preset number of vias to be inspected, for example, such that the inspection area does not exceed the range that the heating device can cover in each heating cycle and / or such that the inspection area can contain at least a preset number of vias. Exemplarily, the current inspection area can be heated in any manner. The heating device used to heat the current detection area can be implemented using any type of heat source, including but not limited to one or more of the following: airflow heat source, laser heat source, infrared light source, microwave heat source, plasma heat source, etc. It is understood that if the current detection area is the entire area of ​​the substrate under test, the entire substrate under test can be heated and subsequent thermal image acquisition can be performed. For example, the microelectronic substrate inspection system can be configured with a preset heating station, and a heating device can be installed at the preset heating station. When the current detection area moves to the preset heating station, the heating device can heat the current detection area. When the current detection area is the entire area of ​​the substrate under test, the entire substrate under test can be moved to the preset heating station for heating.

[0033] The first surface can be any surface of the current detection area. The dielectric substrate itself has vias. After electroplating, there is a metal conductive layer inside the via (i.e., the inner wall conductive layer), and both surfaces of the dielectric substrate also have metal conductive layers (i.e., surface conductive layers). The conductive layers have good thermal conductivity. Therefore, when the current detection area is heated, heat can be conducted through the first surface conductive layer of the first surface, the inner wall conductive layer on the inner wall of the via, to the second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer. The vias on the dielectric substrate described herein can be any type of via, such as TSV, TGV, or vias of any material that may appear in the future.

[0034] In step S120, before the heating control parameters reach the overheating parameter, the current detection area is driven to move to the detection station. The overheating parameter refers to the heating control parameters that cause the detection area of ​​the normal medium plate to reach an overheated state when heating the normal medium plate.

[0035] The normal dielectric plate is a pre-determined dielectric plate without any abnormalities. The detection area of ​​the normal dielectric plate can be the same size as the detection area of ​​the dielectric plate under test. The detection area of ​​the normal dielectric plate may include one or more vias. For example, the normal dielectric plate can be pre-tested, and appropriate heating control parameters can be calibrated by heating the normal dielectric plate to prevent overheating of its detection area. When testing the dielectric plate under test, heating can be performed using the pre-calibrated heating control parameters based on the normal dielectric plate to minimize overheating of its detection area. The above calibration operation is optional; the heating control parameters that prevent the normal dielectric plate from overheating can also be determined theoretically. Of course, it is understood that the dielectric plate under test may have different thermal conductivity than the normal dielectric plate due to abnormalities; therefore, whether heating the dielectric plate under test according to the calibrated heating control parameters can specifically prevent overheating of its detection area is uncertain. For example, the heating control parameters may include heating time and / or heating intensity. In one embodiment, a normal dielectric plate can be heated until it begins to overheat, and the heating control parameter at this point can be calibrated as the overheating parameter. When heating the current detection area of ​​the dielectric plate under test, the heating control parameter can be controlled based on the known overheating parameter. Before the heating control parameter reaches the overheating parameter, the current detection area is moved to a detection station without a heating device to end the heating process. In another embodiment, a normal dielectric plate can be heated, and a suitable heating control parameter can be calibrated as a preset heating parameter before it reaches an overheating state. When heating the current detection area of ​​the dielectric plate under test, the current detection area can be moved to a detection station without a heating device to end the heating process once the heating control parameter reaches the preset heating parameter. In this way, even without calibrating the magnitude of the overheating parameter, it is possible to avoid heating the dielectric plate under test to an overheating state as much as possible. Of course, optionally, both the overheating parameter and the preset heating parameter can be calibrated. Those skilled in the art will understand that an overheated state refers to a state in which, during the heating process, the heat in the detection area gradually increases and begins to dissipate (i.e., it has a certain gradient), until the heat distribution within the entire detection area becomes uniform (i.e., the heat distribution gradient within the entire detection area is equal to or essentially equal to 0). When the detection area reaches an overheated state, the human eye may observe the detection area as a uniformly similar red color. However, in the thermal image acquired of the detection area, the detection area will appear to have a uniform and high temperature (if the higher the temperature, the closer the pixel value of the thermal image is to the pixel value corresponding to red, then the entire area will also appear to have a uniformly similar red color in the thermal image).When the detection area reaches an overheated state, the heat distribution of the entire detection area becomes uniform, with no gradient between heat distributions or a basically uniform temperature distribution. This makes it difficult to identify even if there are abnormalities in the dielectric substrate. Therefore, it is important to avoid heating the dielectric substrate to an overheated state as much as possible, which can facilitate the subsequent identification of abnormalities in the dielectric substrate based on thermal images.

[0036] It is understandable that, similar to the test substrate, when heating a normal substrate, any first surface of the test area of ​​the normal substrate can be heated. The heat can be conducted through the first surface conductive layer of the first surface and the inner wall conductive layer on the inner wall of the via to the second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer.

[0037] The microelectronic dielectric substrate inspection system can also be configured with an inspection station. A heating device can be installed at the preset heating station to heat the dielectric substrate. At the inspection station, no heating device is required. When the current inspection area is moved from the preset heating station to the inspection station, the state of the current inspection area can change from a heating state to a heated state. At this point, there is no heat dissipated from the heat source in the current inspection area, only residual heat on the conductive layer. If a first thermal image of the current inspection area is acquired during continuous heating at the preset heating station to detect the heat distribution in the heat conduction area, the heat in the heat conduction area is not simply heat conducted from the conductive layer of the dielectric substrate under test, but may also include heat dissipated from the vias. That is, the heat distribution in the heat conduction area is easily affected by the heat dissipated by the heat source itself, resulting in a superimposed effect of two types of heat. This leads to inaccurate judgment of the heat conduction effect of the conductive layer of the dielectric substrate under test, thus affecting the accuracy of anomaly detection. The inspection station, without a heat source, avoids the above-mentioned influence and helps improve the accuracy of anomaly detection. For example, when the heating of the current detection area reaches a preset level, specifically when the heating control parameters reach a preset heating parameter (such as a first preset heating parameter), the current detection area can be moved from the preset heating station to the detection station.

[0038] In step S130, a first thermal image is acquired, which is taken toward the second surface of the current detection area located at the detection station.

[0039] The microelectronic dielectric substrate inspection system may also include an image acquisition device, which can acquire thermal images of the dielectric substrate. The image acquisition device can be any type of device capable of acquiring thermal images, including but not limited to infrared cameras. For example, the image acquisition device can use linear or area array infrared cameras, or multiple infrared cameras can be combined to create a larger field of view to increase inspection speed. Alternatively, a transport module can be used to move the dielectric substrate under test, acquiring and inspecting images area by area to complete the inspection of the entire substrate. The aforementioned image acquisition device can be installed at the inspection station to acquire a first thermal image of the second surface of the current inspection area located at the inspection station. Figure 2 A schematic diagram illustrating heating a dielectric substrate and acquiring an image according to an embodiment of the present invention is shown. See also Figure 2 The image shows a dielectric substrate 210, a heating device 220, and an image acquisition device 230. Furthermore, Figure 2 Two stations are also shown: a preset heating station and a testing station. A heating device 220 is installed at the preset heating station, while no heating device is installed at the testing station. The dielectric plate 210 can be either the dielectric plate to be tested or a normal dielectric plate. The dielectric plate 210 has vias 212. Figure 2 Four vias 212 are shown. Figure 2 In the illustrated embodiment, the area containing the four vias 212 can be considered as the detection area, and the heating device 220 can simultaneously heat these four vias 212. The image acquisition device 230 can acquire thermal images of the detection area located at the detection station.

[0040] In step S140, based on the actual heat distribution of the heat conduction area around the via center in the first thermal image, it is determined whether there is an abnormality in the dielectric substrate under test. The heat conduction area is the conductive area surrounding the via area on the second surface conductive layer.

[0041] The via region is the area where the via hole is located. The thermal conduction region is the conductive area surrounding the via region. Figure 3 A schematic diagram of the via region and the heat conduction region according to an embodiment of the present invention is shown. See also Figure 3The image shows a dielectric substrate 310, on which via regions and heat conduction regions corresponding to nine vias are shown. The via region is a circular area 312 enclosed in a solid circle around the center of each via, and the heat conduction region is an annular area 314 located between the dashed and solid lines around the center of each via. The heat conduction region is at least a portion of the area where heat can diffuse or conduct. Exemplarily, the size of the heat conduction region can be determined manually or automatically set by a microelectronic dielectric substrate detection system. Exemplarily, the size of the heat conduction region can be set as a preset size as needed, or it can be set according to the heat distribution in the thermal image. For example, an annular area of ​​a preset size can be taken around the via region as the heat conduction region, or an annular area with a temperature within a preset temperature range can be taken around the via region as the heat conduction region. The preset temperature range can be set as needed, for example, it can be greater than or equal to a certain temperature threshold (which can be called a first preset temperature threshold).

[0042] In one embodiment, the location information of each via on a dielectric substrate (the substrate under test or a normal substrate) can be predetermined. The location information may include one or more of the following: the location of the via center on the substrate, the location of the via region surrounding the via center on the substrate, and the location of the heat conduction region surrounding the via center on the substrate. After acquiring a thermal image of the substrate (which may be the first thermal image or the second thermal image described herein), the first via region and / or the first heat conduction region corresponding to each via can be determined in the thermal image based on the predetermined location information of each via. For the substrate under test, when determining the first heat conduction region using the via location information, the presence of an anomaly in the substrate under test can be determined based on the actual heat distribution of the first heat conduction region itself, or by comparing the actual heat distribution of the first heat conduction region with the standard heat distribution of the heat conduction region of a normal substrate (e.g., the first standard heat distribution described herein). The standard heat distribution can be determined based on a normal substrate, which will be described below.

[0043] In another embodiment, the second via region and / or second heat conduction region corresponding to each via in the thermal image can be determined based on the heat distribution in the thermal image. If the heating is stopped by moving the current detection region to the detection station after heating the current detection region to a certain degree, and a thermal image is acquired towards the second surface of the dielectric substrate after heating is stopped, since there is residual heat conducted through the conductive layer around the via, while there is virtually no heat dissipated above the via hole due to the absence of a heat source below, there is a large temperature difference between the via region and the heat conduction region in the acquired thermal image. The temperature at the via region will be lower than the temperature of the heat conduction region, forming a certain temperature discontinuity. Therefore, the temperatures of each region in the thermal image can be compared. If the temperature of any region is lower than that of the annular region surrounding it and the temperature difference between the region and the annular region surrounding it is greater than a preset temperature threshold (which can be called the second preset temperature threshold), then the region can be determined as the via region, and the annular region surrounding it is the heat conduction region. When the thermal image is a temperature distribution image, the temperature distribution curve around the center of the via can approximate the shape of a Gaussian bell jar curve, and there is a certain temperature discontinuity between the via region and the heat conduction region. For example, a suitable second preset temperature threshold can be determined through a first temperature calibration step to distinguish and identify the via region and the heat conduction region. The first temperature calibration step may include: heating the first surface of a normal dielectric plate, and when the heating control parameters reach a certain preset temperature to determine the heating parameters (which can be referred to as the first preset temperature determining the heating parameters), and ending the heating process by moving the dielectric plate to another station without a heating device, acquiring a second thermal image facing the second surface of the normal dielectric plate, and setting the second preset temperature threshold based on the temperature difference between the via region and the heat conduction region in the second thermal image. Because the heat distribution in the second thermal image of the normal dielectric plate is relatively standard, a suitable second preset temperature threshold can be set based on this thermal image to facilitate the identification of the via region and the heat conduction region in the first thermal image of the dielectric plate under test based on the second preset temperature threshold. The aforementioned first preset temperature heating parameter is a heating control parameter used to determine the second preset temperature threshold. It can be, for example, the first preset heating parameter described herein, or a heating control parameter different from the first preset heating parameter. Exemplarily, the second preset temperature threshold can be equal to or less than the temperature difference between the via region and the heat conduction region in the second thermal image acquired during the first temperature calibration step. Preferably, the difference between the second preset temperature threshold and the temperature difference between the via region and the heat conduction region in the second thermal image acquired during the first temperature calibration step is less than a certain temperature difference threshold. Figure 4 A schematic diagram showing the temperature distribution curve corresponding to any via according to an embodiment of the present invention is provided. Figure 4The temperature distribution curve is a standard temperature distribution curve in the thermal image of the normal medium plate after heating is completed by moving the medium plate to another station without a heating device. Figure 4 The temperature distribution curves shown represent the temperatures at various points on the via when viewed from a direction parallel to the first or second surface of the dielectric substrate. Thermal images acquired towards the second surface of the dielectric substrate can contain the temperatures at various points on that second surface; therefore... Figure 4 The temperature distribution curve shown is equivalent to the temperature distribution curve obtained by projecting a thermal image acquired towards the second surface of the dielectric plate onto any projection plane perpendicular to either the first or second surface. Figure 4 In the diagram, the horizontal axis D represents the location point, and the vertical axis T represents the temperature. See also... Figure 4 This shows the curved portion 410 corresponding to the via region and the curved portion 420 corresponding to the heat conduction region. Figure 4 As can be seen, there is a significant temperature discontinuity between these two regions. It is understandable that when there is an anomaly in the inner wall conductive layer and / or the surrounding surface conductive layer of the via in the dielectric substrate under test, the heat distribution around the center of the via will be affected. In this case, the second via region and / or the second heat conduction region determined based on the heat distribution around the center of the via in the thermal image may deviate from the actual via region and / or heat conduction region (i.e., the first via region and / or the first heat conduction region). In this case, the second heat conduction region determined based on the thermal image can be considered the actual heat conduction region when performing step S140. Of course, the above method for determining the second via region and / or the second heat conduction region can be implemented when the anomaly in the dielectric substrate under test is not significant, for example, when there is only a slight anomaly. According to the image processing method, the via region can be fitted into a circle and the surrounding heat conduction region can be fitted into a ring. However, when the anomaly in the dielectric substrate under test is too large, there may be situations where the via region and heat conduction region cannot be determined based on the thermal image. For example, for the dielectric substrate under test, the presence of any abnormality can be determined based on the actual heat distribution of the second heat conduction area itself, or by comparing the actual heat distribution of the second heat conduction area with the standard heat distribution of the heat conduction area of ​​a normal dielectric substrate (e.g., the first standard heat distribution described herein) to determine whether there is any abnormality in the dielectric substrate under test.

[0044] In another embodiment, the first via region and / or first heat conduction region corresponding to each via can be determined in the thermal image based on the location information of each via, and the second via region and / or second heat conduction region corresponding to each via in the thermal image can be determined based on the heat distribution in the thermal image. For the dielectric substrate under test, the first heat conduction region and the second heat conduction region can be combined to determine whether the dielectric substrate under test has any abnormalities. For example, the positions of the first heat conduction region and the second heat conduction region can be compared, and the presence of any abnormalities in the dielectric substrate under test can be determined based on the positional deviation.

[0045] For example, the heat distribution described herein (including actual heat distribution and standard heat distribution) can be represented by a temperature distribution gradient. Theoretically, if the dielectric substrate under test is normal, the material distribution of the inner wall conductive layer inside the via and the surface conductive layer around the via is relatively uniform and standard (i.e., the same or basically the same as a normal dielectric substrate), and the heat distribution of the heat conduction area around the center of the via will also be relatively standard. If there are abnormalities in the inner wall conductive layer and / or the surface conductive layer of the dielectric substrate under test, such as certain areas of the inner wall conductive layer and / or the surface conductive layer being plated thicker or thinner, it will cause changes in the heat distribution of the heat conduction area in the thermal image. For example, there may be an area in the heat conduction area with a higher / lower temperature than other areas in the same annular area, or a large deviation compared to the heat distribution of a normal dielectric substrate. Therefore, by observing the actual heat distribution of the heat conduction area around the center of the via in the first thermal image, it is possible to determine whether there is an abnormality in the dielectric substrate under test. This method can also detect abnormalities relatively accurately when they exist inside the via. For example, if an abnormality is determined to exist on the medium board under test, a prompt message can be output to remind the user to check the medium board under test.

[0046] Silicon or glass materials inherently possess very high heat resistance, so heating them to hundreds or even thousands of degrees Celsius will not significantly affect the dielectric substrate; for example, it will not affect the material's hardness or cause warping upon cooling. The dielectric substrate can be inspected by detecting the heat distribution in thermal images. Therefore, one surface of the dielectric substrate under test can be actively heated, and the heat distribution on the other surface can be quickly detected to determine if the substrate is abnormal. The high thermal conductivity of the metal conductive layer means that anomalies in the metal conductive layer on the inner wall of the via under test will significantly affect the heat conducted to the other surface of the dielectric substrate. Therefore, this method has high accuracy and efficiency in detecting anomalies in the vias. Furthermore, this inspection method is performed before packaging, thus offering a proactive approach that improves production efficiency and reduces costs. A more preferable approach is to perform the microelectronic dielectric substrate inspection after via plating and before wiring. At this stage, the dielectric substrate is made of a single material, the conductive layer is uniformly distributed, and there is no interference, resulting in higher inspection accuracy. Of course, testing can also be performed after the wiring of the substrate under test.

[0047] The aforementioned technical solution heats one surface of the current detection area of ​​the dielectric substrate under test when the current detection area is located at a preset heating station. Then, the current detection area is moved to the detection station, and the actual heat distribution within the heat conduction area around the via center is detected on the other surface to determine any anomalies in the dielectric substrate. This solution achieves high-precision, high-efficiency, and non-destructive detection of dielectric substrate anomalies, and can detect anomalies in both the internal and / or external conductive layers of the vias, providing comprehensive detection. Furthermore, when determining anomalies by observing the heat distribution within the heat conduction area around the via center, directly acquiring thermal images at the preset heating station can affect the accuracy of the assessment due to the combined effects of heat conduction from the metal conductive layer and heat emitted by the heat source itself. Acquiring thermal images at the detection station avoids the influence of the heat source itself, improving the accuracy of the assessment and further enhancing the accuracy of anomaly detection. In addition, the above solution performs heating and thermal image acquisition at different workstations, which can facilitate streamlined operations. For example, when the current detection area is heated and moved to the detection workstation for image acquisition, the next detection area of ​​the current test medium board or any detection area of ​​another test medium board can be moved to the preset heating workstation for heating, and so on in a cyclical manner.

[0048] For example, before the heating control parameters reach the overheating heating parameters, driving the current detection area to the detection station includes: heating the current detection area and waiting until the heating control parameters reach the first preset heating parameters before driving the current detection area to the detection station; wherein, the first preset heating parameters refer to the heating control parameters that enable the heat distribution in the heat conduction area around the via center in the second thermal image acquired from the second surface of the detection area facing the normal dielectric plate to meet the corresponding target heat distribution requirements when the first surface of the detection area of ​​the normal dielectric plate is heated.

[0049] The target heat distribution requirement corresponding to the first preset heating parameter can be referred to as the first target heat distribution requirement. The first target heat distribution requirement can be that the detection area does not reach an overheated state, and the heat distribution consistency within each annular region of the heat conduction area around the via center within the detection area meets the preset consistency requirement (which can be referred to as the first preset consistency requirement), and the heat distribution gradient between the annular regions is greater than a preset gradient threshold (which can be referred to as the first preset gradient threshold). The heat conduction area can include multiple annular regions, and the position and size of the annular regions can be determined by the calibration personnel when calibrating the heating control parameters. The goal of heating is to make the heat distribution within each annular region of the heat conduction area sufficiently uniform, and to have a sufficiently large heat distribution gradient between different annular regions. If the heating time is too short, the heat has not yet dispersed, which may result in an insufficient heat distribution gradient. If the heating time is too long, it may lead to overheating. After overheating, the heat in the entire heat conduction area will also become globally uniform, resulting in an insufficient heat distribution gradient. An insufficient heat distribution gradient is not conducive to accurately judging the abnormality of the conductive layer of the dielectric substrate under test. The first preset heating parameter refers to the heating parameters that, when heating the first surface of a normal dielectric substrate, ensure that the heat distribution within the heat conduction area around the via center in the second thermal image acquired from the second surface of the normal dielectric substrate meets the corresponding first target heat distribution requirement. In this case, when testing the dielectric substrate under test, during the heating of the current testing area, once the heating control parameters reach the first preset heating parameter, a first thermal image is acquired from the second surface of the current testing area. The acquired first thermal image can be analyzed, and based on the actual heat distribution within the heat conduction area around the via center in the first thermal image, it can be determined whether the dielectric substrate under test exhibits any abnormalities.

[0050] It should be noted that for each preset heating parameter described herein, the heating states when acquiring the first thermal image and the second thermal image can be consistent or inconsistent. Preferably, the heating states when acquiring the second thermal image and the first thermal image should be kept as consistent as possible. For example, for the first preset heating parameter, the corresponding second thermal image can be acquired under the following conditions: when the detection area of ​​the normal dielectric plate is located at the preset heating station, the first surface of the detection area at the preset heating station is heated; when the heating control parameter reaches a specific preset heating parameter, the detection area of ​​the normal dielectric plate is driven to move to the detection station, and a second thermal image is acquired towards the second surface of the detection area at the detection station. Of course, the above scheme is only an example. For the first preset heating parameter, the corresponding second thermal image can also be acquired under the following conditions: when the detection area of ​​the normal dielectric plate is located at the preset heating station, the first surface of the detection area at the preset heating station is heated; when the heating control parameter reaches a specific preset heating parameter, a second thermal image is acquired towards the second surface of the detection area at the detection station while maintaining heating or while controlling the heating device to stop heating. The first preset heating parameter is the specific preset heating parameter that determines when the heat distribution in the heat conduction area around the via center in the second thermal image meets the corresponding target heat distribution requirements. For example, the first preset heating parameter can be determined by calibrating the heating control parameters. During calibration, the heating operation on the normal dielectric plate and the acquisition of the second thermal image can be repeatedly performed. Each time, after selecting any specific preset heating parameter and performing heating and acquiring the second thermal image according to that specific preset heating parameter, it can be determined whether the heat distribution in the heat conduction area around the via center in the second thermal image meets the corresponding target heat distribution requirements. If it does not meet the requirements, other specific preset heating parameters can be selected to continue heating and acquiring the second thermal image until the heat distribution in the heat conduction area around the via center in the second thermal image meets the corresponding target heat distribution requirements.

[0051] Using the above scheme, the heating and image acquisition of the current detection area can be controlled based on the first preset heating parameters. The first preset heating parameters are the heating parameters that are predetermined by a normal dielectric plate so that the heat distribution in the heat conduction area meets the corresponding target heat distribution requirements. In this way, the heating effect of the dielectric plate under test can be controlled based on the preset standard to help obtain a more ideal heating effect, such as making it easier to identify abnormalities of the dielectric plate.

[0052] For example, determining whether the dielectric substrate under test is abnormal based on the actual heat distribution of the heat conduction area around the via center in the first thermal image includes: determining whether the dielectric substrate under test is abnormal based on the actual heat distribution in the heat conduction area in the first thermal image and the first standard heat distribution; wherein, the first standard heat distribution refers to the heat distribution in the heat conduction area in the second thermal image acquired when the detection area of ​​a normal dielectric substrate is heated to the first preset heating parameter.

[0053] The actual heat distribution in the heat conduction area can reflect the abnormality of the inner wall conductive layer and / or surface conductive layer inside the via. During or after heating, due to the thermal conductivity effect of the conductive layer, heat can further diffuse onto the conductive layer outside the via area. If at least a portion of the heat conduction area corresponding to any via in the first thermal image (which can be called the first specific area) has a temperature significantly lower or higher than other areas within the same annular area as the first specific area, for example, if the temperature difference is greater than a third preset temperature threshold, it may be because at least a portion of the inner wall conductive layer perpendicular to the first specific area or at least a portion of the surface conductive layer located within the first specific area is plated too thin or too thick. Since the abnormality in this case is quite complex, it may be an abnormality of the inner wall conductive layer inside the hole, or an abnormality of the outer surface conductive layer, or both. Therefore, it can be determined that the entire dielectric substrate under test is abnormal, and the specific cause of the abnormality can be further determined using other methods. For example, the actual heat distribution in the heat conduction area corresponding to each via in the first thermal image can also be compared with the first standard heat distribution in the heat conduction area of ​​a normal dielectric substrate. For example, the similarity between the actual heat distribution within the heat conduction area corresponding to each via in the first thermal image and the first standard heat distribution within the heat conduction area of ​​a normal dielectric substrate can be determined. If the similarity between any one or more vias is less than a preset similarity threshold (which can be called the first preset similarity threshold), then it can be determined that the dielectric substrate under test is abnormal. Another example is determining the temperature difference between the heat conduction area corresponding to each via in the first thermal image and the heat conduction area of ​​a normal dielectric substrate. If the inner wall conductive layer or surface conductive layer at a certain location is plated too thick / thin, it may cause the temperature of some areas within the heat conduction area to be higher / lower than the standard temperature of the corresponding area within the heat conduction area of ​​the normal dielectric substrate, because a thicker conductive layer has better thermal conductivity. Therefore, if, within the heat conduction area corresponding to any via in the first thermal image, at least some areas (which can be called the second specific area) have an average temperature difference exceeding a preset temperature threshold (which can be called the fourth preset temperature threshold) compared to the corresponding area of ​​the heat conduction area of ​​the normal dielectric substrate, then it can be determined that the dielectric substrate under test is abnormal. The average temperature difference can be obtained by averaging all the differences between the temperature at each location point in the second specific region of the dielectric substrate under test and the temperature at the corresponding location point in the corresponding region of a normal dielectric substrate. For example, in the above scheme of determining the first heat conduction region in the first thermal image based on the via location information and determining the second heat conduction region based on the heat distribution in the first thermal image, the positions of the first and second heat conduction regions can also be compared. If the positional deviation between the two exceeds a preset deviation threshold (which can be called the first preset deviation threshold), it can be determined that the dielectric substrate under test has an anomaly.

[0054] The above-mentioned scheme determines the abnormality of the dielectric plate under test by comparing the actual heat distribution in the heat conduction area in the first thermal image with the first standard heat distribution corresponding to the normal dielectric plate. Because this scheme compares with the heat distribution of the normal dielectric plate, it has high flexibility and accuracy in detection.

[0055] For example, the heat conduction regions corresponding to two adjacent vias on the dielectric substrate under test are independent of each other.

[0056] The heat conduction area can be manually selected or determined based on preset conditions. For example, preset conditions may include, for instance, selecting a pre-defined annular area of ​​a preset size as the heat conduction area around the via area, or selecting an annular area with a temperature within a preset temperature range around the via area as the heat conduction area. The heat conduction areas corresponding to any two adjacent vias can be independent of each other, i.e., there is no overlap between them. This avoids interference between the heat conduction areas of two vias, which could affect the detection accuracy when detecting anomalies in the dielectric substrate based on the heat distribution of the heat conduction area.

[0057] For example, the detection step further includes: before the heating control parameter reaches the overheating parameter and during the heating of the current detection area, acquiring a first thermal image of the second surface of the current detection area located at the preset heating station; and determining whether there is an internal abnormality in the test medium plate based on the actual heat distribution of the via area around the via center in the first thermal image of the via taken towards the preset heating station.

[0058] In this embodiment, which is to acquire a first thermal image of the second surface of the current detection area located at the preset heating station, the via area and the heat conduction area in the first thermal image can also be determined by the above-mentioned method based on the location information of the via and / or by the method based on the heat distribution in the thermal image.

[0059] In one embodiment, the first via region and / or first heat conduction region corresponding to each via can be determined in the thermal image based on the pre-determined location information of each via. In this case, when determining whether there is an abnormality in the via of the dielectric substrate under test based on the actual heat distribution of the via region in the first thermal image taken towards the preset heating station, the determination can be based on the actual heat distribution of the first via region itself, or the determination can be based on comparing the actual heat distribution of the first via region with the standard heat distribution of the via region of a normal dielectric substrate (e.g., the second standard heat distribution described herein).

[0060] In another embodiment, the second via region and / or second heat conduction region corresponding to each via in the thermal image can be determined based on the heat distribution in the thermal image. When acquiring a thermal image during the heating of the dielectric substrate, since there is a heat source below the via, the heat from the heat source can be directly dissipated through the via hole to the area above the via, that is, directly dissipated from below the first surface of the dielectric substrate to above the second surface through the via hole. Therefore, if a thermal image is acquired facing the second surface of the dielectric substrate during heating, the temperature difference between the via region and the heat conduction region will be significant in this thermal image, with the temperature in the via region being higher, indicating a certain temperature discontinuity between the two. This is in conjunction with the above... Figure 4 The situation is similar, except the temperature relationship between the via region and the heat conduction region is reversed. Therefore, the temperatures of different regions in the thermal image can be compared. If any region has a higher temperature than the surrounding annular region, and the temperature difference between this region and the surrounding annular region is greater than a preset temperature threshold (which can be called the fifth preset temperature threshold), then this region can be identified as a via region, and the surrounding annular region as a heat conduction region. The fifth preset temperature threshold can be equal to or different from the aforementioned second preset temperature threshold. For example, a suitable fifth preset temperature threshold can be determined through a second temperature calibration step to distinguish and identify the via region and the heat conduction region. The second temperature calibration step may include: heating the first surface of the normal dielectric plate, and when the heating control parameters reach a certain preset temperature (which can be called the second preset temperature heating parameter), acquiring a second thermal image facing the second surface of the normal dielectric plate while maintaining heating, and setting the fifth preset temperature threshold based on the temperature difference between the via region and the heat conduction region in the second thermal image. Because the heat distribution in the second thermal image of a normal dielectric substrate is relatively standard, a suitable fifth preset temperature threshold can be set based on this thermal image to facilitate the identification of via regions and heat conduction regions in the first thermal image of the dielectric substrate under test based on this fifth preset temperature threshold. The aforementioned second preset temperature determination heating parameter is a heating control parameter used to determine the fifth preset temperature threshold. It can be, for example, the second preset heating parameter described herein, or a heating control parameter different from the second preset heating parameter. For example, the fifth preset temperature threshold can be equal to or less than the temperature difference between the via region and the heat conduction region in the second thermal image acquired during the second temperature calibration step. Preferably, the difference between the fifth preset temperature threshold and the temperature difference between the via region and the heat conduction region in the second thermal image acquired during the second temperature calibration step is less than a certain temperature difference threshold. Figure 5 A schematic diagram showing the temperature distribution curve corresponding to any via according to another embodiment of the present invention is provided. Figure 5 The temperature distribution curve is a standard temperature distribution curve from the thermal images acquired during the heating of a normal dielectric plate. Figure 5The temperature distribution curves shown represent the temperatures at various points on the via when viewed from a direction parallel to the first or second surface of the dielectric substrate. Figure 5 In the diagram, the horizontal axis D represents the location point, and the vertical axis T represents the temperature. See also... Figure 5 This shows the curved portion 510 corresponding to the via region and the curved portion 520 corresponding to the heat conduction region. Figure 5 As can be seen, there is a significant temperature discontinuity between the two regions. For example, when determining the second via region based on the heat distribution in the first thermal image for the dielectric substrate under test, the presence of an anomaly can be determined based on the actual heat distribution of the second via region itself, or by comparing the actual heat distribution of the second via region with the standard heat distribution of the via region of a normal dielectric substrate (e.g., the second standard heat distribution described herein) to determine whether an anomaly exists in the dielectric substrate under test.

[0061] In another embodiment, the first via region and / or first heat conduction region corresponding to each via can be determined in the thermal image based on the location information of each via, and the second via region and / or second heat conduction region corresponding to each via in the thermal image can be determined based on the heat distribution in the thermal image. In this case, when determining whether there is an internal anomaly in the dielectric substrate under test based on the actual heat distribution of the via region in the first thermal image taken towards the preset heating station, the first via region and the second via region can be combined to determine whether there is an internal anomaly in the dielectric substrate under test. For example, the positions of the first via region and the second via region can be compared, and the presence of an internal anomaly in the dielectric substrate under test can be determined based on the positional deviation.

[0062] The actual heat distribution in the via area can reflect any abnormalities in the conductive layer inside the via. During heating, because there is a heat source below the via, the heat from the heat source can be directly dissipated through the via hole to the area above the via, that is, from below the first surface of the dielectric substrate through the via hole to above the second surface. Therefore, the presence of any abnormalities within the via in the dielectric substrate can be determined by detecting the penetration of the heating airflow on the second surface. An image acquisition device can also be installed at the preset heating station. The image acquisition device can be similar to the one at the detection station, and will not be elaborated here. If the acquisition range of the image acquisition device is large enough to cover both the preset heating station and the detection station simultaneously, the image acquisition device at the preset heating station and the image acquisition device at the detection station can be the same. If the acquisition range of the image acquisition device is not large enough, different image acquisition devices can be used at the two stations. When using an image acquisition device to take images towards the via, theoretically, the heat source below can be captured through the via, but this is not a true physical image capture because the via is usually very small in diameter. Therefore, the main function is to capture the hot air or heat passing through the via. For example, the shooting method can be vertical or tilted depending on the selected heat source. Generally, gas heat sources can be shot at an angle, which can more accurately capture the heat distribution after passing through the aperture.

[0063] For example, anomalies within the via may include the presence of foreign objects within the via, uneven thickness of the conductive layer on the inner wall, and / or blockage of the via hole. Foreign objects may include dust, air bubbles, etc. Uneven thickness of the conductive layer on the inner wall may be caused by the presence of foreign objects within the via, and blockage of the via hole may be caused by excessive foreign objects within the via and / or excessively thick conductive layer plating on the inner wall. For example, if at least a portion of the via region corresponding to any via in the first thermal image (which may be referred to as the third specific region) has a temperature significantly lower than other regions within the same annular region as the third specific region, for example, if the temperature difference is greater than a sixth preset temperature threshold, it may be because at least a portion of the conductive layer on the inner wall perpendicular to the third specific region within the via hole contains foreign objects, resulting in uneven heat distribution within the inner wall via region. In this case, it can be determined that the dielectric substrate under test has an anomaly within the via. For example, the actual heat distribution within the via region corresponding to each via in the first thermal image can also be compared with the standard heat distribution within the via region of a normal dielectric substrate. For example, the similarity between the actual heat distribution within the via region corresponding to each via in the first thermal image and the standard heat distribution within the via region of a normal dielectric substrate can be determined. If the similarity between any one or more vias is less than a preset similarity threshold (which can be called the second preset similarity threshold), it can be determined that the dielectric substrate under test has an internal anomaly. The second preset similarity threshold can be equal to or different from the first preset similarity threshold. Another example is determining the temperature difference between the via region corresponding to each via in the first thermal image and the via region of a normal dielectric substrate. If there are too many foreign objects inside the via or the conductive layer on the inner wall is plated too thickly, the via may be at least partially blocked, resulting in at least a portion of the temperature within the via region being lower than the standard temperature of the via region of a normal dielectric substrate. Therefore, if the average temperature difference between at least a portion of the via region corresponding to any via in the first thermal image (which can be called the fourth specific region) and the corresponding region of the via region of a normal dielectric substrate exceeds a preset temperature threshold (which can be called the seventh preset temperature threshold), it can be determined that the dielectric substrate under test has an internal anomaly. The average temperature difference can be obtained by averaging all the differences between the temperature at each location point in the fourth specific region of the dielectric substrate under test and the temperature at the corresponding location point in the corresponding region of the normal dielectric substrate. For example, in the above scheme of determining the first via region in the first thermal image based on the via location information and determining the second via region based on the heat distribution in the first thermal image, the positions of the first and second via regions can also be compared. If the positional deviation between the two exceeds a preset deviation threshold (which can be called the second preset deviation threshold), it can be determined that there is an anomaly within the via in the dielectric substrate under test. The second preset deviation threshold can be equal to or different from the first preset deviation threshold.In the scheme of determining whether there is an abnormality in the via of the medium plate under test based on the actual heat distribution of the via area in the first thermal image, the corresponding first thermal image is the first thermal image collected during the heating process. For example, it is the first thermal image collected while maintaining heating when the current detection area is heated and the heating control parameter reaches the first preset heating parameter.

[0064] By adopting the above method, the actual heat distribution in the via area around the via center can be used to determine the abnormality in the via of the medium plate under test. In this way, the abnormality can be identified more accurately when it exists in the via. This method has strong targeting and more accurate detection results.

[0065] For example, driving the current detection area to the detection station includes: first determining, based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station, that there is no abnormality inside the via in the medium board under test, and then driving the current detection area to the detection station.

[0066] First, when the current detection area is located at the preset heating station, a first thermal image is acquired, and the actual heat distribution of the via area in the first thermal image is used to determine whether there is an anomaly in the medium board under test. If an anomaly is found within the via in the medium board under test, anomaly response operations such as outputting prompt information can be performed. Since an anomaly has been determined in the medium board under test, subsequent operations to determine whether the medium board under test is abnormal based on the heat distribution of the heat conduction area at the detection station are unnecessary, which can greatly save computation and improve detection speed. If no anomaly is found within the via in the medium board under test based on the first thermal image taken of the current detection area located at the preset heating station, subsequent analysis of the anomaly situation of the medium board under test based on the heat distribution of the heat conduction area at the detection station can continue, which can improve the comprehensiveness of anomaly detection of the medium board under test and reduce the missed detection rate.

[0067] For example, before the heating control parameters reach the overheating heating parameters and during the heating of the current detection area, a first thermal image is captured towards the second surface of the current detection area located at a preset heating station. This includes: while heating the current detection area and waiting until the heating control parameters reach the second preset heating parameters, a first thermal image is captured towards the preset heating station. The second preset heating parameters refer to the heating parameters that, when heating the first surface of the detection area of ​​the normal dielectric plate, enable the heat distribution within the via area around the via center in the second thermal image captured towards the second surface of the detection area of ​​the normal dielectric plate to meet the corresponding target heat distribution requirements.

[0068] The target heat distribution requirement corresponding to the second preset heating parameter can be referred to as the second target heat distribution requirement. The second target heat distribution requirement can be that the detection area does not reach an overheated state, and the heat distribution consistency within each annular region of the via area surrounding the via center within the detection area meets the preset consistency requirement (which can be referred to as the second preset consistency requirement), and the heat distribution gradient between the annular regions is greater than the preset gradient threshold (which can be referred to as the second preset gradient threshold). Similar to the heat conduction area, the via area can include multiple annular regions. The position and size of the annular regions can be determined by the calibration personnel during the calibration of the heating control parameters. The goal of heating is to make the heat distribution within each annular region of the via area sufficiently uniform, and to have a sufficiently large heat distribution gradient between different annular regions. The heat distribution gradient can be considered as the gradient in the radial direction of the via area, and the radial direction can be considered as the direction of heat diffusion or heat conduction. If the heating time is too short, the heat has not yet dispersed, which may result in an insufficient heat distribution gradient. If the heating time is too long, it may lead to overheating. After overheating, the heat in the entire via area will become globally uniform, resulting in an insufficient heat distribution gradient. An insufficient heat distribution gradient is not conducive to judging the abnormality of the conductive layer on the inner wall of the via. The second preset heating parameter refers to the heating control parameters that, when heating the first surface of a normal dielectric substrate, ensure that the heat distribution within the via region around the via center in the second thermal image acquired from the second surface of the normal dielectric substrate meets the corresponding second target heat distribution requirements. In this case, when testing the dielectric substrate under test, during the heating of the current testing area, once the heating control parameters reach the second preset heating parameter, a first thermal image is acquired from the second surface of the current testing area. The acquired first thermal image can be analyzed, and based on the actual heat distribution within the via region around the via center in the first thermal image, it can be determined whether the dielectric substrate under test exhibits any abnormalities.

[0069] As described above, for each preset heating parameter described herein, the heating scenario for acquiring the first thermal image and the second thermal image is consistent. For example, for the second preset heating parameter, the corresponding second thermal image can be acquired under the following conditions: when the detection area of ​​the normal dielectric substrate is located at the preset heating station, the first surface of the detection area located at the preset heating station is heated, and when the heating control parameter reaches a specific preset heating parameter, a second thermal image is acquired towards the second surface of the detection area located at the detection station while maintaining heating. The specific preset heating parameter when the heat distribution in the via area around the via center in the second thermal image meets the corresponding target heat distribution requirements is the second preset heating parameter. Exemplarily, the second preset heating parameter can be determined by calibrating the heating control parameter using a calibration method. During calibration, the heating operation on the normal dielectric substrate and the acquisition of the second thermal image can be performed repeatedly. Each time, after selecting any specific preset heating parameter and performing heating and acquiring the second thermal image according to the specific preset heating parameter, it can be determined whether the heat distribution in the via area around the via center in the second thermal image meets the corresponding target heat distribution requirements. If it does not meet the requirements, other specific preset heating parameters can be selected to continue heating and acquiring the second thermal image until the heat distribution in the via area around the via center in the second thermal image meets the corresponding target heat distribution requirements.

[0070] Using the above scheme, the heating and image acquisition of the current detection area can be controlled based on the second preset heating parameters. The second preset heating parameters are the heating parameters that are predetermined by the normal dielectric plate so that the heat distribution in the via area meets the corresponding target heat distribution requirements. In this way, the heating effect of the dielectric plate under test can be controlled based on the preset standard to help obtain a more ideal heating effect, such as making it easier to identify abnormalities of the dielectric plate.

[0071] For example, determining whether there is an internal anomaly in the dielectric substrate under test based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station includes: determining whether there is an internal anomaly in the dielectric substrate under test based on the actual heat distribution in the via area in the first thermal image taken towards the preset heating station and the second standard heat distribution; wherein, the second standard heat distribution refers to the heat distribution of the via area in the second thermal image collected when a normal dielectric substrate is heated to the second preset heating parameter.

[0072] As described above, the presence of anomalies in the dielectric substrate under test can be determined solely based on the actual heat distribution within the via area in the first thermal image. Alternatively, anomaly detection can be made by combining the actual heat distribution of the via area of ​​the dielectric substrate under test with the standard heat distribution of the via area of ​​a normal dielectric substrate. Specifically, the actual heat distribution within the via area of ​​the dielectric substrate under test when heated to the same degree can be compared with the standard heat distribution within the via area of ​​a normal dielectric substrate to determine if there are any anomalies within the vias. This method of comparing with standard heat distribution is applicable to a wide range of scenarios and offers high flexibility and accuracy in detection.

[0073] For example, the method further includes the following heating calibration step for calibrating heating control parameters: heating the first surface of the detection area of ​​the normal dielectric plate, wherein heat can be conducted through the first surface conductive layer of the first surface of the normal dielectric plate and the inner wall conductive layer on the inner wall of the via on the normal dielectric plate to the second surface conductive layer of the second surface of the normal dielectric plate, and continue to be conducted on the second surface conductive layer of the normal dielectric plate; before the heating control parameters reach the overheating heating parameters, acquiring a second thermal image of the second surface of the detection area of ​​the normal dielectric plate; determining whether the target thermal distribution requirements are met based on the thermal distribution of the target area in the second thermal image, and calibrating the heating control parameters when the target thermal distribution requirements are met as preset heating parameters corresponding to the target thermal distribution requirements, wherein the target area includes the via area and / or the thermal conduction area.

[0074] In one embodiment, the target area is a heat conduction area, and the preset heating parameter can be a first preset heating parameter, with the corresponding target heat distribution requirement being a first target heat distribution requirement. In another embodiment, the target area is a via area, and the preset heating parameter can be a second preset heating parameter, with the corresponding target heat distribution requirement being a second target heat distribution requirement. In yet another embodiment, the target area includes a via area and a heat conduction area. In this case, the preset heating parameter can include a first preset heating parameter and a second preset heating parameter, and the target heat distribution requirement can include a first target heat distribution requirement corresponding to the first preset heating parameter and a second target heat distribution requirement corresponding to the second preset heating parameter. The calibration methods for the first and second preset heating parameters can be understood based on the above description and will not be elaborated here.

[0075] By adopting the above calibration scheme, appropriate preset heating parameters can be calibrated in advance by heating a normal dielectric plate and acquiring thermal images. This allows the system to assist in calibrating the heating control parameters, thereby improving calibration efficiency.

[0076] For example, the substrate under test has multiple sets of vias, and the area where each set of vias is located is used as the current detection area to perform the detection steps.

[0077] The vias of the substrate under test can be divided into multiple groups, and each group may include one or more vias. The number of vias in any two groups can be the same or different. The vias in any two groups can be partially the same or completely different. The grouping of vias can be set as needed, and this invention does not limit this. For example, see [link to documentation]. Figure 3 The substrate under test contains 9 vias in 3 rows and 3 columns. Each row of vias can be treated as a group, and the above detection steps can be performed on one row of vias at a time. All vias can be detected by performing the above steps three times.

[0078] For example, the detection step further includes: determining the quality consistency among the multiple vias based on the actual heat distribution around the center of each of the multiple vias in the first thermal image.

[0079] Multiple vias are the vias involved in the quality consistency judgment. They can be all the vias on the test substrate or a portion of the vias on the test substrate. For example, the actual heat distribution of the target areas corresponding to multiple vias on the test substrate can be compared to each other to determine quality consistency. For instance, the similarity between the actual heat distribution of the target areas corresponding to every two vias (i.e., a via pair) on the test substrate can be determined. If the number of via pairs with a similarity greater than a preset similarity threshold (which can be called the third preset similarity threshold) is greater than a preset number threshold (which can be called the first preset number threshold), it can be determined that the quality consistency among the multiple vias meets the requirements; otherwise, it can be determined that the quality consistency among the multiple vias does not meet the requirements. For example, the actual heat distribution of the target area corresponding to multiple vias on the test substrate can be compared with the standard heat distribution of the target area corresponding to vias on a normal substrate. This determines the similarity between the actual heat distribution of each target area corresponding to multiple vias on the test substrate and the standard heat distribution. The number of vias with a similarity greater than a preset similarity threshold (the first preset similarity threshold when the target area is a heat conduction area, and the second preset similarity threshold when the target area is a via area) is then determined to be greater than a preset number threshold (which can be called the second preset number threshold). If so, the quality consistency requirement is met; otherwise, the quality consistency requirement is not met. For example, assuming the actual heat distribution of the heat conduction area corresponding to 10 vias on the test substrate is compared with the first standard heat distribution, if the number of vias with a similarity greater than 90% exceeds 8, the quality consistency requirement of the test substrate is met. By adopting the above scheme and adding quality consistency judgment, the scheme of this embodiment can not only detect the abnormality of a single via and the conductive layer around it, but also detect the quality consistency between multiple vias. This can improve the detection breadth of the dielectric board, so as to more comprehensively detect the packaging quality of micro-dots.

[0080] For example, the heating device used to heat the first surface of the current detection area is a heat flow type heat source.

[0081] By using a heat flow-type heat source, heat can be better dissipated to the other side through the through-holes during heating, and heat can also be conducted over a wider area through the conductive layer, which helps to further improve detection accuracy.

[0082] According to another aspect of the present invention, a microelectronic dielectric substrate inspection device is also provided. (See also...) Figure 6The diagram shown is a schematic block diagram of a microelectronic dielectric substrate inspection device 600 according to an embodiment of the present invention. Through-holes are formed on the dielectric substrate. The microelectronic dielectric substrate inspection device 600 includes an inspection module for performing inspection steps on the inspection area of ​​the dielectric substrate under test. The inspection module includes:

[0083] The heating submodule 610 is used to heat the first surface of the current detection area located at the preset heating station. In the current detection area, heat can be conducted through the first surface conductive layer of the first surface and the inner wall conductive layer on the inner wall of the via to the second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer.

[0084] The drive submodule 620 is used to drive the current detection area to the detection station before the heating control parameters reach the overheating heating parameters. The overheating heating parameters refer to the heating control parameters that cause the detection area of ​​the normal medium plate to reach an overheated state when heating the normal medium plate.

[0085] The acquisition submodule 630 is used to acquire a first thermal image of the second surface of the current inspection area located at the inspection station;

[0086] The determination submodule 640 is used to determine whether there is an abnormality in the dielectric substrate under test based on the actual heat distribution of the heat conduction area around the center of the via in the first thermal image. The heat conduction area is the conductive area on the second surface conductive layer surrounding the via area.

[0087] According to another aspect of the present invention, an electronic device is also provided. See also... Figure 7 As shown, it is a schematic block diagram of an electronic device 700 according to an embodiment of the present invention. Figure 7 As shown, the electronic device includes a processor 710 and a memory 720, wherein the memory 710 stores computer program instructions, which are executed by the processor 710 to perform the microelectronic substrate detection method described above.

[0088] According to another aspect of the present invention, a storage medium is also provided, on which program instructions are stored. When the program instructions are executed by a computer or processor, the computer or processor performs the corresponding steps of the microelectronic substrate detection method described in the embodiments of the present invention, and is used to implement the corresponding modules in the microelectronic substrate detection method apparatus according to the embodiments of the present invention, or the corresponding modules in the microelectronic substrate detection method apparatus described above. The storage medium may, for example, include a memory card of a smartphone, a storage component of a tablet computer, a hard disk of a personal computer, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a portable compact disc read-only memory (CD-ROM), a USB memory, or any combination of the above storage media. A computer-readable storage medium may be any combination of one or more computer-readable storage media.

[0089] According to another aspect of the present invention, a computer program product is also provided, including computer program instructions, which, when executed, are used to perform the microelectronic substrate detection method as described above.

[0090] Those skilled in the art can understand the specific implementation and beneficial effects of the above-described microelectronic substrate testing device, electronic device, storage medium, and computer program product by reading the detailed description of the microelectronic substrate testing method. For the sake of brevity, further details will not be repeated here.

[0091] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of the invention. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

[0092] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0093] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0094] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0095] Similarly, it should be understood that, in order to streamline the invention and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of the invention. However, this approach should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with fewer features than all of those in a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0096] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0097] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0098] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules in the microelectronic substrate inspection apparatus according to embodiments of the present invention. The present invention can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0099] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0100] The above are merely specific embodiments or descriptions of the present invention, and the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for detecting microelectronic dielectric substrates, characterized in that, Through-holes are formed on the dielectric substrate, and the following detection steps are performed on the detection area of ​​the dielectric substrate to be tested: The first surface of the current detection area located at the preset heating station is heated, wherein, within the current detection area, heat can be conducted through the first surface conductive layer of the first surface and the inner wall conductive layer on the inner wall of the via to the second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer; Before the heating control parameters reach the overheating parameter, the current detection area is driven to move to the detection station. The overheating parameter refers to the heating control parameters that cause the detection area of ​​the normal medium plate to reach an overheated state when heating the normal medium plate. A first thermal image is captured toward the second surface of the current detection area located at the detection station; Based on the actual heat distribution of the heat conduction area around the via center in the first thermal image, it is determined whether the dielectric substrate under test has any abnormalities. The heat conduction area is the conductive area surrounding the via area on the second surface conductive layer.

2. The method according to claim 1, characterized in that, The step of driving the current detection area to the detection station before the heating control parameters reach the overheating parameter includes: The current detection area is heated, and when the heating control parameters reach the first preset heating parameters, the current detection area is driven to move to the detection station. The first preset heating parameter refers to the heating control parameter that enables the heat distribution in the heat conduction area around the via center in the second thermal image acquired from the second surface of the detection area of ​​the normal dielectric plate to meet the corresponding target heat distribution requirements when the first surface of the detection area of ​​the normal dielectric plate is heated.

3. The method according to claim 2, characterized in that, The step of determining whether the dielectric substrate under test has any abnormalities based on the actual heat distribution of the heat conduction area around the via center in the first thermal image includes: Based on the actual heat distribution within the heat conduction area in the first thermal image and the first standard heat distribution, determine whether the medium plate under test has any abnormalities; The first standard thermal distribution refers to the thermal distribution within the heat conduction area in the second thermal image acquired when the detection area of ​​the normal dielectric plate is heated to the first preset heating parameter.

4. The method according to any one of claims 1-3, characterized in that, The heat conduction regions corresponding to two adjacent vias of the medium plate under test are independent of each other.

5. The method according to claim 1, characterized in that, The detection steps also include: Before the heating control parameters reach the overheating parameters and during the heating process of the current detection area, a first thermal image is captured toward the second surface of the current detection area located at the preset heating station. Based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station, it is determined whether there is an abnormality inside the via in the medium plate under test.

6. The method according to claim 5, characterized in that, The process of driving the current detection area to the detection station includes: First, based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station, if it is determined that there is no abnormality inside the via in the medium board under test, then the current detection area is driven to move to the detection station.

7. The method according to claim 5, characterized in that, The first thermal image acquired, taken toward the second surface of the current detection area located at the preset heating station, before the heating control parameters reach the overheating parameter and during the heating process of the current detection area, includes: While heating the current detection area, and waiting until the heating control parameters reach the second preset heating parameters, the first thermal image is captured facing the preset heating station. The second preset heating parameter refers to the heating parameter that enables the heat distribution in the via area around the via center in the second thermal image acquired from the second surface of the detection area of ​​the normal dielectric plate to meet the corresponding target heat distribution requirements when the first surface of the detection area of ​​the normal dielectric plate is heated.

8. The method according to claim 7, characterized in that, The step of determining whether there is an internal anomaly in the dielectric substrate under test based on the actual heat distribution of the via area around the via center in the first thermal image taken towards the preset heating station includes: Based on the actual heat distribution within the via area in the first thermal image taken towards the preset heating station and the second standard heat distribution, it is determined whether there is an abnormality inside the via in the medium plate under test. The second standard thermal distribution refers to the thermal distribution of the via area in the second thermal image collected when the normal dielectric plate is heated to the second preset heating parameter.

9. The method according to claim 2 or 7, characterized in that, The method further includes the following heating calibration step for calibrating the heating control parameters: The first surface of the detection area of ​​the normal dielectric plate is heated. In the detection area, the heat can be conducted through the first surface conductive layer of the first surface of the normal dielectric plate and the inner wall conductive layer on the inner wall of the via on the normal dielectric plate to the second surface conductive layer of the second surface of the normal dielectric plate, and continue to be conducted on the second surface conductive layer of the normal dielectric plate. Before the heating control parameters reach the overheating parameters, a second thermal image is captured on the second surface of the detection area facing the normal dielectric plate. Based on the heat distribution of the target area in the second thermal image, it is determined whether it meets the target heat distribution requirements, and the heating control parameters when the target heat distribution requirements are met are calibrated as preset heating parameters corresponding to the target heat distribution requirements. The target area includes the via area and / or the heat conduction area.

10. The method according to any one of claims 1-3, characterized in that, The substrate under test has multiple sets of vias. The detection steps are performed sequentially, with the area where each set of vias is located as the current detection area.

11. A microelectronic dielectric substrate testing device, characterized in that, The dielectric substrate has vias formed, and includes a detection module. The detection module is used to perform detection steps on the detection area of ​​the dielectric substrate under test. The detection module includes: The heating submodule is used to heat the first surface of the current detection area located at the preset heating station. In the current detection area, heat can be conducted through the first surface conductive layer of the first surface and the inner wall conductive layer on the inner wall of the via to the second surface conductive layer of the second surface, and continue to be conducted on the second surface conductive layer. The driving submodule is used to drive the current detection area to the detection station before the heating control parameters reach the overheating heating parameters. The overheating heating parameters refer to the heating control parameters that cause the detection area of ​​the normal medium plate to reach an overheated state when heating the normal medium plate. The acquisition submodule is used to acquire a first thermal image of the second surface of the current detection area located at the detection station; The determination submodule is used to determine whether there is an abnormality in the dielectric substrate under test based on the actual heat distribution of the heat conduction area around the center of the via in the first thermal image. The heat conduction area is the conductive area surrounding the via area on the second surface conductive layer.

12. An electronic device comprising a processor and a memory, characterized in that, The memory stores computer program instructions, which, when executed by the processor, are used to perform the microelectronic substrate detection method as described in any one of claims 1-10.

13. A storage medium on which program instructions are stored, characterized in that, The program instructions, when executed, are used to perform the microelectronic substrate detection method as described in any one of claims 1-10.

14. A computer program product comprising computer program instructions, characterized in that, The computer program instructions, when executed, are used to perform the microelectronic substrate detection method as described in any one of claims 1-10.

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