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

Abstract

Embodiments of the present application disclose a microelectronic medium plate detection method and device, electronic equipment and storage medium. The method comprises: heating the first surface of the detection area of the normal medium plate at the preset heating station; before the detection area reaches the overheating state, collecting the first thermal image shot towards the second surface of the detection area, when the thermal distribution in the target area around the via center of the first thermal image meets the corresponding target thermal distribution requirement, marking the heating control parameter at this time as the preset heating parameter; heating the first surface of the current detection area of the to-be-detected medium plate at the preset heating station, and when the heating control parameter reaches the preset heating parameter, collecting the second thermal image shot towards the second surface of the current detection area, and determining whether the to-be-detected medium plate has an abnormality according to the actual thermal distribution of the target area around the via center in the second thermal image. By calibrating the preset heating parameter, the abnormality detection accuracy can be improved.

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 microelectronic dielectric substrate testing method, a microelectronic dielectric substrate testing device, an electronic device, a storage medium, and a computer program product.

[0005] According to one aspect of the present invention, a method for detecting microelectronic dielectric substrates is provided. Through-holes are formed on the dielectric substrate. The method includes: a heating calibration step: heating a first surface of the detection area of ​​a normal dielectric substrate at a preset heating station; within the detection 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 through-hole to a second surface conductive layer on the second surface, and continue to be conducted on the second surface conductive layer; before the detection area reaches an overheated state, acquiring a first thermal image of the second surface facing the detection area; and when the heat distribution in the target area around the through-hole center in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heating control parameters at this time as preset heating parameters; and performing the following detection steps on the detection area of ​​the dielectric substrate under test: heating the first surface of the current detection area at a preset heating station; and when the heating control parameters reach the preset heating parameters, acquiring a second thermal image of the second surface facing the current detection area; and determining whether the dielectric substrate under test has an abnormality based on the actual heat distribution in the target area around the through-hole center in the second thermal image.

[0006] For example, the heating calibration step further includes: when the heat distribution in the target area around the via center in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heat distribution in the target area at this time as the standard heat distribution; determining whether the dielectric substrate under test has an abnormality based on the actual heat distribution in the target area around the via center in the second thermal image, including: determining whether the dielectric substrate under test has an abnormality based on the actual heat distribution in the target area around the via center in the second thermal image and the standard heat distribution.

[0007] For example, the heating calibration step specifically includes: acquiring a first thermal image of the second surface of the detection area located at the preset heating station while maintaining heating, and calibrating the heating control parameter at this time as the first preset heating parameter when the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements; the detection step specifically includes: acquiring a second thermal image of the second surface of the current detection area located at the preset heating station while maintaining heating when the heating control parameter reaches the first preset heating parameter.

[0008] For example, the target area includes a via area and a heat conduction area; the heat conduction area is the conductive area surrounding the via area on the second surface conductive layer; wherein, the heating calibration step specifically includes: when the heat distribution in the via area and / or the heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameter at this time is calibrated as the first preset heating parameter; the detection step specifically includes: when the heating control parameter reaches the first preset heating parameter, a second thermal image is acquired towards the second surface of the current detection area located at the preset heating station while maintaining heating, and the actual heat distribution in the via area around the via center in the second thermal image and the actual heat distribution in the heat conduction area around the via center in the second thermal image are used to comprehensively determine whether the dielectric substrate under test is abnormal.

[0009] For example, the target area includes a via area and a heat conduction area; the heat conduction area is the conductive area surrounding the via area on the second surface conductive layer; wherein, the calibration step specifically includes: when the heat distribution in the via area and the heat conduction area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at two moments are sequentially calibrated as first preset heating parameters; the detection step specifically includes: when the heating control parameters sequentially reach the first preset heating parameters corresponding to the via area and the heat conduction area, a second thermal image is captured towards the second surface of the current detection area located at the preset heating station while maintaining heating; based on the actual heat distribution of the via area around the center of the via in the second thermal image captured corresponding to the via area, and based on the actual heat distribution of the heat conduction area around the center of the via in the second thermal image captured corresponding to the heat conduction area, it is comprehensively determined whether the dielectric substrate under test is abnormal.

[0010] For example, the target area includes a heat conduction area; the heat conduction area is a conductive area surrounding the via area on the second surface conductive layer; the heating calibration step specifically includes: acquiring a first thermal image of the second surface of the detection area located at the preset heating station while heating is stopped, and calibrating the heating control parameter at this time as the second preset heating parameter when the heat distribution in the heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements; the detection step specifically includes: acquiring a second thermal image of the second surface of the current detection area located at the preset heating station while heating is stopped when the heating control parameter reaches the second preset heating parameter.

[0011] For example, the target area includes a heat conduction area; the heat conduction area is a conductive area surrounding the via area on the second surface conductive layer; the heating calibration step specifically includes: moving the detection area to the detection station, acquiring a first thermal image of the second surface of the detection area located at the detection station, and when the heat distribution in the heat conduction area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heating control parameter at this time as the third preset heating parameter; the detection step specifically includes: when the heating control parameter reaches the third preset heating parameter, moving the current detection area to the detection station, and acquiring a second thermal image of the second surface of the current detection area located at the detection station.

[0012] For example, the heat conduction regions corresponding to two adjacent vias on the dielectric substrate under test are independent of each other.

[0013] 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.

[0014] For example, the via is a through-silicon via or a through-glass via.

[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 heating calibration module, used to heat the first surface of the testing area of ​​a normal dielectric substrate at a preset heating station, wherein in the testing 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; and before the testing area reaches an overheated state, acquiring a first thermal image of the second surface facing the testing area, and when the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heating control parameters at this time as preset heating parameters; and a testing module, used to perform the following testing steps on the testing area of ​​the dielectric substrate under test: heating the first surface of the current testing area at a preset heating station, and when the heating control parameters reach the preset heating parameters, acquiring a second thermal image of the second surface facing the current testing area, and determining whether there is an abnormality in the dielectric substrate under test based on the actual heat distribution in the target area around the center of the via in the second thermal image.

[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 above technical solution determines the preset heating parameters corresponding to the heat distribution of the target area around the via center of the standard dielectric plate when the heat distribution meets the target heat distribution requirements through the heating calibration step. This allows the heating effect of the heating device to be controlled as needed, which helps to obtain the heat distribution of the dielectric plate under test when heating it, making it easier to identify abnormalities in the dielectric plate, and thus helps to improve the accuracy of abnormality detection of the dielectric plate.

[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 allows for the calibration of suitable preset heating parameters for a normal dielectric substrate through a heating calibration step, followed by heating and thermal image acquisition of the dielectric substrate under test according to the calibrated preset heating parameters. The presence of anomalies in the dielectric substrate is then determined based on the thermal distribution of the target area around the via center in the acquired thermal image. This approach effectively controls the heating effect of the dielectric substrate under test, improving the accuracy of anomaly detection. The microelectronic dielectric substrate detection method includes a heating calibration step and a detection step performed 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 may be the entire area of ​​the dielectric substrate or a portion thereof. Figure 1 A schematic flowchart of a microelectronic dielectric substrate inspection method according to an embodiment of the present invention is shown. Figure 1 As shown, the detection steps include a heating calibration step S110 and a detection step S120.

[0031] In step S110, the first surface of the detection area of ​​the normal dielectric board is heated at the preset heating station. Within the 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 detection area reaches an overheated state, a first thermal image is captured facing the second surface of the detection area. When the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as preset heating parameters.

[0032] The microelectronic dielectric substrate inspection method can be executed by a processor in a microelectronic dielectric substrate inspection system. Exemplarily, the microelectronic dielectric substrate inspection system may also include a transport module on which dielectric substrates (including the dielectric substrate under test and the normal dielectric substrate 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 dielectric substrate between various workstations or to move different inspection areas of the dielectric substrate to workstations. The inspection area of ​​a normal dielectric substrate may include one or more vias. The size of the inspection area of ​​a normal dielectric substrate can be set as needed, for example, it can be set at least according to the heating range of the heating device and / or the preset number of vias to be inspected, such as ensuring that the inspection area does not exceed the range that the heating device can cover in each heating cycle and / or ensuring that the inspection area can contain at least the preset number of vias. Exemplarily, the normal dielectric substrate and the dielectric substrate under test described below can be heated in any manner. The heating device used to heat the dielectric substrate 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 detection area is the entire area of ​​a normal dielectric substrate, the entire normal dielectric substrate can be heated and subsequently thermally imaged. For example, the microelectronic dielectric 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 detection area of ​​the normal dielectric substrate moves to the preset heating station, the heating device can heat the detection area. When the detection area is the entire area of ​​the normal dielectric substrate, the entire normal dielectric substrate can be moved to the preset heating station for heating.

[0033] The first surface can be any surface of the 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 detection area is heated, 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 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] Before the detection area of ​​the normal dielectric substrate reaches an overheated state, a first thermal image is acquired facing the second surface of the detection area. The microelectronic dielectric substrate inspection system may also include an image acquisition device to 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 detection speed. Alternatively, a transport module can be used to move the dielectric substrate area by area for image acquisition and inspection to complete the inspection of the entire dielectric substrate. 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. The dielectric substrate 210 can be a normal dielectric substrate or a dielectric substrate under test. The dielectric substrate 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 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. It should be noted that... Figure 2 The illustrated scheme for acquiring thermal images at a preset heating station where the heating device is located is merely an example and not a limitation of the present invention. Alternatively, thermal images can also be acquired at other stations without a heating device (such as the detection station described herein).

[0035] The normal dielectric plate is a pre-determined dielectric plate without any abnormalities. It can be pre-tested using a normal dielectric plate, and appropriate heating control parameters can be calibrated by heating it to prevent overheating of the 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 the detection area. However, it is understood that the thermal conductivity of the dielectric plate under test may differ from that of the normal dielectric plate due to abnormalities; therefore, whether heating the dielectric plate under test according to the calibrated heating control parameters will specifically prevent overheating of the detection area is uncertain. For example, the heating control parameters may include heating time and / or heating intensity. A suitable heating control parameter can be calibrated as a preset heating parameter before the normal dielectric plate reaches an overheated state. 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, to the naked eye, the detection area may appear as a uniform red color throughout. However, in the thermal image acquired of the detection area, it will appear as having 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 it will also appear as a uniform red color throughout the thermal image). When the detection area reaches an overheated state, the heat distribution within 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 to facilitate subsequent identification of abnormalities based on thermal images.

[0036] When calibrating using a normal dielectric substrate, the heat distribution within the target area in the acquired first thermal image can be monitored until the heat distribution meets the corresponding target heat distribution requirements. At this point, the heating control parameters are calibrated as preset heating parameters. For example, the heat distribution described herein (including actual and standard heat distribution) can be represented by a temperature distribution gradient. For example, the target area may include a via area and / or a heat conduction area. A via area is the area where the via hole is located. A heat conduction area is the conductive area surrounding the via area on the second surface conductive layer. 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 are shown the via regions and heat conduction regions corresponding to nine vias. 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 set to 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).

[0037] The target thermal distribution requirements can be set as needed. For example, the target thermal distribution requirements may include, for instance, that the thermal distribution consistency within each annular region of the target area meets a preset consistency requirement and that the thermal distribution gradient between the annular regions is greater than a preset gradient threshold. The thermal distribution within the target area has a certain distribution gradient, and the thermal distribution within the same annular region is relatively uniform. This makes it easier to identify anomalies in the test substrate when the thermal distribution does not meet this pattern.

[0038] In step S120, the first surface of the current detection area is heated at a preset heating station, and when the heating control parameters reach the preset heating parameters, a second thermal image is captured on the second surface facing the current detection area. Based on the actual heat distribution of the target area around the via center in the second thermal image, it is determined whether there is an abnormality in the medium plate under test.

[0039] The current detection area is the area on the substrate under test that is currently being tested. The size of the detection area on the substrate under test can be the same as the size of the detection area on a normal substrate. For example, the size of each detection area on the substrate under test can be set at least according to the heating range of the heating device and / or the preset number of vias to be tested, such as ensuring that the detection area does not exceed the range that the heating device can cover in each heating cycle and / or ensuring that the detection area can contain at least the preset number of vias.

[0040] Theoretically, if the substrate under test is normal, the material distribution of the inner conductive layer and the surrounding surface conductive layer within the vias will be relatively uniform and standard (i.e., the same or essentially the same as a normal substrate), and the heat distribution around the center of the vias will also be relatively standard. If the inner conductive layer and / or the surface conductive layer of the substrate under test are abnormal, such as the presence of dust, bubbles, or other foreign matter on the inner conductive layer within the vias, or certain areas of the inner conductive layer and / or the surface conductive layer being plated too thickly or too thinly, the heat distribution in at least the via area in the thermal image will change. For example, there may be an area within the via area with a lower temperature than other areas, or a significant deviation from the heat distribution of a normal substrate. Therefore, by observing the actual heat distribution around the center of the vias in the second thermal image, it is possible to determine whether the substrate under test is abnormal. This method can also detect abnormalities relatively accurately when they exist inside the vias. For example, if an abnormality is determined in the substrate under test, a prompt message can be output to remind the user to inspect the substrate under test.

[0041] 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, nor will it 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. The presence of abnormalities in the dielectric substrate can then be determined based on the heat distribution. A preferable approach is to perform the inspection after via plating and before wiring on the dielectric substrate under test. At this time, because the dielectric substrate material is uniform, the conductive layer is evenly distributed, and there is no interference, the inspection accuracy is higher. Of course, inspection can also be performed after wiring on the dielectric substrate under test. It should be noted that the wiring state of a normal dielectric substrate is consistent with the wiring state of the dielectric substrate under test during the heating calibration step and the inspection step. Abnormalities in the dielectric substrate under test are determined by heating one surface of the dielectric substrate under test and then detecting the actual heat distribution around the via center on the other surface. The high thermal conductivity of the metal conductive layer means that any abnormalities on the inner wall and / or surrounding metal conductive layer of the via will significantly affect the heat transfer to the other surface of the substrate under test. Therefore, this method offers high accuracy and efficiency in detecting abnormalities in the substrate under test, and the obtained test results are stable and reliable. Furthermore, this detection method is performed before packaging, thus offering a proactive approach that not only improves production efficiency but also reduces costs.

[0042] The above technical solution determines the preset heating parameters corresponding to the heat distribution of the target area around the via center of the standard dielectric plate when it meets the target heat distribution requirements through the heating calibration step. This allows for control of the heating effect of the heating device as needed, which helps to obtain a heat distribution that is easy to identify when heating the dielectric plate under test. For example, by determining the preset heating parameters, situations such as excessively high heating temperature can be avoided, which can easily cause the dielectric plate to overheat and exhibit a uniform heat distribution, thereby affecting the accuracy of judging the thermal conductivity of the dielectric plate.

[0043] For example, the heating calibration step further includes: when the heat distribution in the target area around the via center in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heat distribution in the target area at this time as the standard heat distribution; determining whether the dielectric substrate under test has an abnormality based on the actual heat distribution in the target area around the via center in the second thermal image, including: determining whether the dielectric substrate under test has an abnormality based on the actual heat distribution in the target area around the via center in the second thermal image and the standard heat distribution.

[0044] When calibrating preset heating parameters, the standard thermal distribution corresponding to a normal dielectric substrate can also be calibrated. When the thermal distribution within the target area around the via center in the first thermal image meets the corresponding target thermal distribution requirements, the thermal distribution within that target area is considered the standard thermal distribution. The actual thermal distribution within the target area corresponding to each via in the second thermal image can be compared with the standard thermal distribution within the target area of ​​the normal dielectric substrate. For example, when the target area is a via area, the similarity between the actual thermal distribution within the via area corresponding to each via in the second thermal image and the standard thermal distribution within the via area of ​​the 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), it can be determined that the dielectric substrate under test has an anomaly within the via. For another example, the temperature difference between the via area corresponding to each via in the second thermal image and the via area of ​​the normal dielectric substrate can also be determined. 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 blocked, causing at least part of the temperature within the via area to be lower than the standard temperature of the via area of ​​the normal dielectric substrate. Therefore, if, in the first thermal image, at least a portion of the via region (which can be referred to as the first specific region) has an average temperature difference exceeding a preset temperature threshold (which can be referred to as the second preset temperature threshold) compared to the corresponding region of the via region in a normal dielectric substrate, it can be determined that the dielectric substrate under test has an internal anomaly. The average temperature difference can be obtained by averaging all differences after calculating the temperature difference between each location point in the first specific region of the dielectric substrate and the corresponding location point in the corresponding region of the normal dielectric substrate. Similarly, when the target region is a heat conduction region, the similarity between the actual heat distribution within the heat conduction region corresponding to each via in the second thermal image and the standard heat distribution within the heat conduction region of the 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 referred to as the second preset similarity threshold), it can be determined that the dielectric substrate under test has an anomaly. The second preset similarity threshold can be equal to or different from the first preset similarity threshold. For example, the temperature difference between the heat conduction region corresponding to each via in the second thermal image and the heat conduction region of the normal dielectric substrate can also be determined. If the inner wall conductive layer or surface conductive layer at a certain location is plated too thick or too thin, it may cause the temperature of some areas within the heat conduction area to be higher or lower than the standard temperature of the corresponding area within the heat conduction area of ​​a normal dielectric substrate, because the thicker the conductive layer, the better its thermal conductivity. Therefore, if, in the second thermal image, at least some areas (which can be called the second specific area) within the heat conduction area corresponding to any via exceed the average temperature threshold (which can be called the third preset temperature threshold) compared to the corresponding area of ​​the heat conduction area of ​​a normal dielectric substrate, it can be determined that the dielectric substrate under test is abnormal.The average temperature difference can be obtained by averaging all the differences after calculating the temperature difference between each location point in the second specific region of the test medium plate and the corresponding location point in the corresponding region of the normal medium plate.

[0045] By employing the above method, the actual heat distribution within the target area of ​​the tested dielectric substrate when heated to the same degree can be compared with the standard heat distribution within the target area of ​​a normal dielectric substrate to determine whether there are any abnormalities within the holes of the tested dielectric substrate. This method of comparing with standard heat distribution is applicable to a wide range of scenarios and offers high flexibility and accuracy in detection.

[0046] For example, the heating calibration step specifically includes: acquiring a first thermal image of the second surface of the detection area located at the preset heating station while maintaining heating, and calibrating the heating control parameter at this time as the first preset heating parameter when the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements; the detection step specifically includes: acquiring a second thermal image of the second surface of the current detection area located at the preset heating station while maintaining heating when the heating control parameter reaches the first preset heating parameter.

[0047] A second thermal image can be captured towards the second surface of the current detection area located at the preset heating station while maintaining heating. This facilitates anomaly detection, at least through the heat dissipated from the heat source via the via holes. For each preset heating parameter described herein, the heating state when acquiring the second thermal image in the heating calibration step can be consistent with or different from that when acquiring the first thermal image in the detection step. Preferably, the heating state when acquiring the second thermal image should be as consistent as possible with that when acquiring the first thermal image. Therefore, if anomaly detection of the dielectric substrate is required using a second thermal image acquired while maintaining heating, a first thermal image of a normal dielectric substrate can also be acquired while maintaining heating in the heating calibration step.

[0048] In one embodiment, the target area is a via region, the first preset heating parameter can be a first target preset heating parameter, and the corresponding target heat distribution requirement can be a 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 via region within the detection area meets a preset consistency requirement (which can be called the first preset consistency requirement), and the heat distribution gradient between the annular regions is greater than a preset gradient threshold (which can be called the first preset gradient threshold). The via region 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 via region sufficiently uniform, and to have a sufficiently large heat distribution gradient between different annular regions. The heat distribution gradient can be considered as a gradient in the radial direction of the via region, 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, overheating may occur, and after overheating, the heat in the entire via region will become globally uniform, resulting in an insufficient heat distribution gradient. A insufficient thermal gradient is detrimental to determining abnormalities in the conductive layer of the via's inner wall. The first target preset heating parameter refers to the heating parameters that, when heating the first surface of a normal dielectric substrate, ensure the thermal distribution within the via region surrounding the via center in the first thermal image acquired from the second surface of the normal dielectric substrate meets the corresponding first target thermal distribution requirements. In this case, when testing the dielectric substrate under test, a second thermal image can be acquired from the second surface facing the current testing area while heating the current testing area, once the heating control parameters reach the first target preset heating parameter. The acquired second thermal image can be analyzed, and based on the actual thermal distribution within the via region surrounding the via center in the second thermal image, it can be determined whether the dielectric substrate under test exhibits any abnormalities.

[0049] In another embodiment, the target area is a heat conduction area, and the first preset heating parameter can be a second target preset heating parameter, with the corresponding target heat distribution requirement being 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 heat conduction area surrounding the via center in the detection area meets a preset consistency requirement (which can be called the second preset consistency requirement), and the heat distribution gradient between the annular regions is greater than a preset gradient threshold (which can be called the second preset gradient threshold). Similar to the via area, the heat conduction area can include multiple annular regions, the position and size of which can be determined by the calibration personnel during the calibration of the heating control parameters. Furthermore, similar to the via area, the heating objective is to ensure that the heat distribution within each annular region of the heat conduction area is sufficiently uniform, and that there is a sufficiently large heat distribution gradient between different annular regions. If the heating time is too short, the heat may not be dispersed, potentially resulting in an insufficient heat distribution gradient. Conversely, if the heating time is too long, overheating may occur, and after overheating, the heat within the entire heat conduction area will become globally uniform, resulting in an insufficient heat distribution gradient. An insufficient heat distribution gradient is also detrimental to accurately determining the abnormality of the conductive layer of the dielectric substrate under test. The second target preset heating parameter refers to the heating parameters that, when the first surface of a normal dielectric substrate is heated, ensure that the heat distribution within the heat conduction area around the via center in the first thermal image acquired towards 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, a second thermal image can be acquired towards the second surface of the current testing area once the heating control parameters reach the second target preset heating parameter during the heating process of the current testing area. The acquired second thermal image can be analyzed, and based on the actual heat distribution within the heat conduction area around the via center in the second thermal image, it can be determined whether the dielectric substrate under test exhibits any abnormalities.

[0050] In another embodiment, the target region includes a via region and a heat conduction region. In this case, the first preset heating parameter may include a first target preset heating parameter and a second target preset heating parameter, and the target heat distribution requirement may include a first target heat distribution requirement corresponding to the first target preset heating parameter and a second target heat distribution requirement corresponding to the second target preset heating parameter. The calibration method for the first target preset heating parameter and the second target preset heating parameter can be understood based on the above description.

[0051] The first and second target preset heating parameters can be the same or different. When the first and second target preset heating parameters are the same, a second thermal image can be acquired at a single moment, and detection steps can be performed simultaneously on the via region and the heat conduction region based on the first thermal image. When the first and second target preset heating parameters are different, different second thermal images can be acquired at different moments, and detection steps can be performed on the via region and the heat conduction region respectively based on the different second thermal images.

[0052] As described above, for each preset heating parameter described herein, the heating state when acquiring the second thermal image in the heating calibration step and the heating state when acquiring the first thermal image in the detection step can be consistent or inconsistent. Preferably, the heating state when acquiring the second thermal image and the heating state when acquiring the first thermal image should be kept as consistent as possible. For example, for the first target preset heating parameter, the corresponding first 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 first thermal image is acquired towards the second surface of the detection area located at the preset heating station while maintaining heating. The specific preset heating parameter when the heat distribution within the via area around the via center in the first thermal image meets the corresponding target heat distribution requirements is the first target preset heating parameter. For example, for the second target preset heating parameters, the corresponding first 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 parameters reach a specific preset heating parameter, a first thermal image is acquired towards the second surface of the detection area located at the preset heating station while maintaining heating. The specific preset heating parameter when the heat distribution in the heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements is the second target preset heating parameter. During calibration, the above-mentioned heating operation of the normal dielectric substrate and the acquisition operation of the first thermal image can be repeatedly performed. Each time any specific preset heating parameter is selected and heating and first thermal image acquisition are performed according to the specific preset heating parameter, it can be determined whether the heat distribution in the via area or heat conduction area around the via center in the first 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 first thermal image acquisition until the heat distribution in the via area or heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements.

[0053] Using the above method, thermal images of the normal dielectric plate and the dielectric plate under test can be acquired while maintaining heating. This helps to detect anomalies by at least using the heat dissipated from the heat source through the via holes.

[0054] For example, the target area includes a via area and a heat conduction area; the heat conduction area is the conductive area surrounding the via area on the second surface conductive layer; wherein, the heating calibration step specifically includes: when the heat distribution in the via area and / or the heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameter at this time is calibrated as the first preset heating parameter; the detection step specifically includes: when the heating control parameter reaches the first preset heating parameter, a second thermal image is acquired towards the second surface of the current detection area located at the preset heating station while maintaining heating, and the actual heat distribution in the via area around the via center in the second thermal image and the actual heat distribution in the heat conduction area around the via center in the second thermal image are used to comprehensively determine whether the dielectric substrate under test is abnormal.

[0055] As described above, the first target preset heating parameter and the second target preset heating parameter can be the same. That is, the heating control parameters at the moment when the detection area of ​​the normal dielectric substrate is heated until the heat distribution in the via area and / or heat conduction area in the first thermal image meets their respective target heat distribution requirements can be obtained as the first preset heating parameter. Thus, the moment corresponding to the first preset heating parameter is the moment when the heat distribution in the via area and / or heat conduction area in the first thermal image simultaneously meets their respective target heat distribution requirements. By calibrating the first preset heating parameter in this way, the heat distribution of the via area and heat conduction area, which can be used for anomaly detection, can be simultaneously obtained from a single heating image when heating the dielectric substrate under test. This effectively saves heating time and image acquisition time, thus improving detection efficiency.

[0056] In this embodiment, the abnormality of the dielectric substrate under test can be determined by combining the actual heat distribution within the via area around the via center in the second thermal image and the actual heat distribution within the heat conduction area around the via center in the second thermal image. For example, the presence of an in-via abnormality in the dielectric substrate under test can be determined based on the actual heat distribution within the via area in the second thermal image (this can be referred to as the first determination result), and the presence of an abnormality in the dielectric substrate under test can be determined based on the actual heat distribution within the heat conduction area in the second thermal image (this can be referred to as the second determination result). Exemplarily, if either or both of the first and second determination results indicate an abnormality in the dielectric substrate under test, it can be definitively determined that an abnormality exists. If both results indicate that no abnormality exists, it can be definitively determined that no abnormality exists. Alternatively, if both of the first and second determination results indicate an abnormality in the dielectric substrate under test, it can be definitively determined that an abnormality exists. If either or both results indicate that no abnormality exists, it can be definitively determined that no abnormality exists. Determining anomalies in a dielectric substrate by analyzing the heat distribution in the via area during heating is a relatively rapid method for detecting anomalies within the via. Furthermore, combining this method with an auxiliary method that analyzes the heat distribution in the heat conduction area can further improve the detection range of the dielectric substrate, helping to reduce missed and / or false detections of anomalies.

[0057] For example, the target area includes a via area and a heat conduction area; the heat conduction area is the conductive area surrounding the via area on the second surface conductive layer; wherein, the calibration step specifically includes: when the heat distribution in the via area and the heat conduction area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at two moments are sequentially calibrated as first preset heating parameters; the detection step specifically includes: when the heating control parameters sequentially reach the first preset heating parameters corresponding to the via area and the heat conduction area, a second thermal image is captured towards the second surface of the current detection area located at the preset heating station while maintaining heating; based on the actual heat distribution of the via area around the center of the via in the second thermal image captured corresponding to the via area, and based on the actual heat distribution of the heat conduction area around the center of the via in the second thermal image captured corresponding to the heat conduction area, it is comprehensively determined whether the dielectric substrate under test is abnormal.

[0058] As mentioned above, the first target preset heating parameter and the second target preset heating parameter can also be different. When they are different, different second thermal images can be acquired at different times, and detection steps can be performed on the via region and the heat conduction region based on the different second thermal images. The heat in the via region is mainly heat dissipated from the heat source through the via hole, while the heat in the heat conduction region is mainly heat conducted through the conductive layer. Therefore, the heat in the via region diffuses faster in the thermal image, while the heat in the heat conduction region diffuses relatively slower. As a result, the speed at which the two meet their respective target heat distribution requirements may be different, and it is sometimes difficult to find heating control parameters that can make the heat distribution of the via region and the heat conduction region simultaneously meet their respective target heat distribution requirements. Therefore, calibrating the two regions separately can ensure that appropriate first preset heating parameters can be calibrated for both the via region and the heat conduction region. In this embodiment, "based on the actual heat distribution of the via area around the via center in the second thermal image corresponding to the via area, and based on the actual heat distribution of the heat conduction area around the via center in the second thermal image corresponding to the heat conduction area, we comprehensively determine whether the dielectric substrate under test is abnormal" is similar to the implementation method in the previous embodiment, "based on the actual heat distribution of the via area around the via center in the second thermal image, and based on the actual heat distribution of the heat conduction area around the via center in the second thermal image, we comprehensively determine whether the dielectric substrate under test is abnormal", and will not be described in detail here.

[0059] For example, the target area includes a heat conduction area; the heat conduction area is a conductive area surrounding the via area on the second surface conductive layer; the heating calibration step specifically includes: acquiring a first thermal image of the second surface of the detection area located at the preset heating station while heating is stopped, and calibrating the heating control parameter at this time as the second preset heating parameter when the heat distribution in the heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements; the detection step specifically includes: acquiring a second thermal image of the second surface of the current detection area located at the preset heating station while heating is stopped when the heating control parameter reaches the second preset heating parameter.

[0060] Stopping heating means controlling the heating device to stop heating, such as turning off the heating device. A second thermal image can be captured on the second surface of the current detection area located at the preset heating station while heating is stopped, and the abnormality of the tested dielectric substrate can be determined based on the actual heat distribution of the heat conduction area in the second thermal image. In the heating calibration step, a first thermal image of a normal dielectric substrate can also be acquired while maintaining heating.

[0061] If a second thermal image is acquired during continuous heating at a preset heating station to detect the heat distribution in the heat conduction area, the heat in the heat conduction area is not solely due to heat conducted from the conductive layer of the substrate under test. Heat may also be emitted from the vias, meaning the heat distribution is easily affected by the heat emitted from the heat source itself, resulting in a superposition of these two types of heat. This leads to inaccurate judgment of the heat conduction effect of the conductive layer of the substrate under test, thus affecting the accuracy of anomaly detection. For example, heating control parameters can be calibrated during the heating calibration step to obtain suitable second preset heating parameters. These parameters ensure that when the heating control parameters are reached, the heat distribution in the heat conduction area of ​​the acquired first thermal image, after heating has stopped, meets the corresponding target heat distribution requirements. During the detection step, when the heating of the current detection area of ​​the substrate under test reaches the second preset heating parameters, a second thermal image can be acquired again, after heating has stopped, and the anomaly of the substrate under test can be determined based on the heat distribution in the heat conduction area of ​​the acquired second thermal image. This solution avoids the influence of the aforementioned heat sources, effectively improving the accuracy of anomaly detection. Furthermore, the method of controlling the heating device to stop heating eliminates the need to move the current detection area, allowing heating and image acquisition to be performed at the same location, thus reducing the workload of transporting the module.

[0062] For example, the target area includes a heat conduction area; the heat conduction area is a conductive area surrounding the via area on the second surface conductive layer; the heating calibration step specifically includes: moving the detection area to the detection station, acquiring a first thermal image of the second surface of the detection area located at the detection station, and when the heat distribution in the heat conduction area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heating control parameter at this time as the third preset heating parameter; the detection step specifically includes: when the heating control parameter reaches the third preset heating parameter, moving the current detection area to the detection station, and acquiring a second thermal image of the second surface of the current detection area located at the detection station.

[0063] The microelectronic dielectric substrate inspection system can be configured with two different workstations: a preset heating workstation and an inspection workstation. A heating device can be installed at the preset heating workstation to heat the dielectric substrate. At the inspection workstation, no heating device is required. When the current inspection area is moved from the preset heating workstation to the inspection workstation, 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. As mentioned above, if a second thermal image is acquired during continuous heating at the preset heating workstation to detect the heat distribution in the heat conduction area, the accuracy of anomaly detection on the dielectric substrate under test is affected by the heat dissipated from the heat source. The inspection workstation, lacking a heat source, avoids this effect and helps improve the accuracy of anomaly detection. For example, the heating control parameters can be calibrated in the heating calibration step to obtain a suitable third preset heating parameter. This third preset heating parameter ensures that, when the heating control parameter is reached, the heat distribution in the heat conduction area in the first thermal image acquired after moving the inspection area of ​​the normal dielectric substrate to the inspection workstation meets the corresponding target heat distribution requirements. During the testing process, once the current testing area of ​​the substrate under test reaches the third preset heating parameter, the current testing area is moved from the preset heating station to the testing station. A second thermal image is then captured, showing the second surface of the current testing area at the testing station. The heat distribution in the heat conduction area of ​​this second thermal image reflects the heat distribution obtained through conduction by the conductive layer, providing a more accurate picture of the conductive layer's heat conduction effect. This allows for a more accurate determination of whether the substrate under test has any abnormalities. This approach, which involves heating and thermal image acquisition at different stations, facilitates streamlined operations. For example, after the current testing area has been heated and moved to the testing station for image acquisition, the next testing area of ​​the substrate under test, or any testing area of ​​another substrate under test, can be moved to the preset heating station for heating, and this process can be repeated cyclically.

[0064] For example, the heat conduction regions corresponding to two adjacent vias on the dielectric substrate under test are independent of each other.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] For example, determining whether there is an anomaly in the dielectric substrate under test based on the actual heat distribution around the via center in the second thermal image includes: a first determination operation: determining whether there is an anomaly inside the via in the dielectric substrate under test based on the actual heat distribution within the via area around the via center in the second thermal image; and / or, a second determination operation: determining whether there is an anomaly in the dielectric substrate under test based on the actual heat distribution within the heat conduction area around the via center in the second thermal image, wherein the heat conduction area is the conductive area surrounding the via area on the second surface conductive layer.

[0069] In one embodiment, the location information of each via on the 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 via region and / or the first heat conduction region through 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 via region and / or the first heat conduction region itself, or by comparing the actual heat distribution of the first via region and / or the first heat conduction region with a standard heat distribution. As mentioned above, the standard heat distribution can be determined based on a normal substrate.

[0070] 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. For example, since there is a heat source below the via, the heat from the heat source can be directly dissipated from below the first surface of the dielectric plate to above the second surface through the via hole. Therefore, if a thermal image is acquired facing the second surface of the dielectric plate when heating the dielectric plate, the temperature difference between the via region and the heat conduction region is large in the thermal image, with the temperature in the via region being higher, and there is a certain temperature discontinuity between the two. Therefore, the temperatures of each region in the thermal image can be compared. If the temperature of any region is higher 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 fourth 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 fourth preset temperature threshold can be determined through a first temperature calibration step to distinguish and identify via regions and heat conduction regions. The first temperature calibration step may include: heating a first surface of a normal dielectric substrate, and when the heating control parameters reach a certain preset temperature (which may be referred to as the first preset temperature determination heating parameter), acquiring a first thermal image of a second surface facing the normal dielectric substrate while maintaining heating, and setting a fourth preset temperature threshold based on the temperature difference between the via region and the heat conduction region in the first thermal image. Because the heat distribution in the first thermal image of the normal dielectric substrate is relatively standard, a suitable fourth preset temperature threshold can be set based on this thermal image to facilitate the identification of via regions and heat conduction regions in the second thermal image of the dielectric substrate under test based on the fourth preset temperature threshold. The aforementioned first preset temperature determination heating parameter is a heating control parameter used to determine the fourth preset temperature threshold; it may be, for example, the first preset heating parameter described herein, or a heating control parameter different from the first preset heating parameter. For example, the fourth preset temperature threshold may be equal to or less than the temperature difference between the via region and the heat conduction region in the first thermal image acquired in the first temperature calibration step. It is preferable that the difference between the fourth preset temperature threshold and the temperature difference between the via region and the heat conduction region in the first thermal image acquired in 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 4 The temperature distribution curve is a standard temperature distribution curve from the thermal images acquired during the heating of a normal dielectric plate. Figure 4The 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 relatively obvious temperature discontinuity between the two regions.

[0071] If the heating device is stopped after the heating medium plate reaches a certain temperature, or the heating is terminated by moving the medium plate to another station without a heating device, and a thermal image is acquired towards the second surface of the medium plate after heating is stopped, then since there is no heat source at this time, there is still a significant temperature difference between the via region and the heat conduction region in the acquired thermal image. However, the temperature in the via region will be lower than that in the heat conduction region, which appears as a temperature discontinuity in the thermal image. Therefore, in this case, 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 fifth preset temperature threshold), then the region can be identified as the via region, and the annular region surrounding it as the heat conduction region. For example, a suitable fifth preset temperature threshold can be determined through the second temperature calibration step to distinguish and identify the via region and the heat conduction region. The second temperature calibration step may include: acquiring a first thermal image of the second surface of the normal dielectric plate by heating the first surface of the normal dielectric plate, and when the heating control parameters reach a certain preset temperature to determine the heating parameters (which may be referred to as the second preset temperature determination heating parameters), and under the premise that the heating device stops heating or the heating is ended by moving the dielectric plate to another station without a heating device, and setting a fifth preset temperature threshold based on the temperature difference between the via region and the heat conduction region in the first thermal image. Because the heat distribution in the first thermal image of the normal dielectric plate is relatively standard, a suitable fifth preset temperature threshold can be set based on the thermal image to facilitate the identification of the via region and the heat conduction region in the second thermal image of the dielectric plate under test based on the fifth preset temperature threshold. The aforementioned second preset temperature determination heating parameters are heating control parameters used to determine the fifth preset temperature threshold, which may be, for example, the second preset heating parameters or the third preset heating parameters described herein, or heating control parameters different from the second preset heating parameters and the third preset heating parameters. For example, the fifth preset temperature threshold may be equal to or less than the temperature difference between the via region and the heat conduction region in the first thermal image acquired in 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 first thermal image acquired during the second temperature calibration step is less than a certain temperature difference threshold. The fourth preset temperature threshold and the fifth preset temperature threshold can be equal or unequal. 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 in the thermal image of the normal dielectric plate after heating has been stopped by controlling the heating device to stop heating or by moving the dielectric plate to another station without a heating device. Figure 5In 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 are also obvious temperature discontinuities in these two regions.

[0072] 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 via region and / or the second heat conduction region determined based on the thermal image can be regarded as the actual via region and / or heat conduction region to perform the first determination operation and / or the second determination operation. Of course, the above-mentioned scheme for determining the second via region and / or the second heat conduction region can be implemented when the anomaly of the dielectric substrate under test is not very large, 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 of the dielectric substrate under test is too large, there may be situations where the via region and the heat conduction region cannot be determined based on the thermal image. For example, when determining the second via region and / or the second heat conduction region by means of the heat distribution in the second thermal image, the test substrate can be judged to be abnormal based on the actual heat distribution of the second via region and / or the second heat conduction region itself. Alternatively, the test substrate can be judged to be abnormal by comparing the actual heat distribution of the second via region and / or the second heat conduction region with the standard heat distribution of the via region and / or the heat conduction region of a normal substrate.

[0073] 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 presence of an anomaly can be determined by combining the first via region and / or the first heat conduction region and the second via region and / or the second heat conduction region. For example, the positions of the first via region and the second via region can be compared, and / or the positions of the first heat conduction region and the second heat conduction region can be compared, and the presence of an anomaly in the dielectric substrate under test can be determined based on the positional deviation.

[0074] The following describes an exemplary implementation of the first determination operation. Exemplarily, the presence of anomalies within the vias of the dielectric substrate under test can be determined based on the actual heat distribution of the via region around the via center in the second thermal image. The actual heat distribution of the via region reflects anomalies in the conductive layer of the inner wall of the via. As described above, during heating, 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, i.e., directly dissipated from below the first surface of the dielectric substrate to above the second surface through the via hole. Therefore, the presence of anomalies within the vias of the dielectric substrate can be determined by detecting the penetration of the heating gas flow on the second surface. When using an image acquisition device to capture an image towards the via, theoretically, the heat source below can be captured through the via, but this is not a true physical capture, as the via diameter is typically very small. Therefore, the main focus is on capturing the hot gas or heat passing through the via. Exemplarily, the capture method can be selected as vertical or inclined depending on the selected heat source. Generally, gas heat sources require inclined capture to accurately capture the heat distribution after passing through the via. 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. Foreign objects may include dust, air bubbles, etc. Uneven thickness of the conductive layer on the inner wall may be caused by foreign objects within the via, and blockage of the via 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 second 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 second thermal image can also be compared with the standard heat distribution within the via region of a normal dielectric substrate. The method for comparing the actual heat distribution within the via region with the standard heat distribution can be referred to the description above. For example, in the above scheme of determining the first via region in the second thermal image based on the via location information and determining the second via region based on the heat distribution in the second 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 first preset deviation threshold), it can be determined that there is an anomaly within the via in the dielectric substrate under test.

[0075] The following describes an exemplary implementation of the second determination operation. Exemplarily, the presence of an anomaly in the dielectric substrate under test can be determined based on the actual heat distribution of the heat conduction area around the center of the via in the second thermal image. The actual heat distribution of the heat conduction area can reflect anomalies in 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 second thermal image (which may be referred to as the fourth specific area) has a temperature significantly lower or higher than other areas within the same annular region as the fourth specific area, for example, a temperature difference greater than a seventh preset temperature threshold, it is possible that at least a portion of the inner wall conductive layer perpendicular to the fourth specific area or at least a portion of the surface conductive layer located within the fourth specific area is plated too thin or too thick. Since the anomaly in this case is complex, it could be an anomaly in the inner wall conductive layer, an anomaly in 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 anomaly can be further determined using other methods. For example, the actual heat distribution within the heat conduction area corresponding to each via in the second thermal image can be compared with the standard heat distribution within the heat conduction area of ​​a normal dielectric substrate. The method for comparing the actual heat distribution within the heat conduction area with the standard heat distribution can be referred to the description above. For example, in the above scheme of determining the first heat conduction area in the second thermal image based on the via location information and determining the second heat conduction area based on the heat distribution in the second thermal image, the position of the first heat conduction area can also be compared with the position of the second heat conduction area. 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 the dielectric substrate under test has an anomaly. The second preset deviation threshold can be equal to or different from the first preset deviation threshold.

[0076] The first determination operation and the second determination operation can be performed selectively, or both can be performed. When both the first determination operation and the second determination operation are performed, the presence of an anomaly on the test substrate can be determined comprehensively based on the results of the first determination operation (i.e., the first determination result described above) and the results of the second determination operation (i.e., the second determination result described above). The method of comprehensive determination can be referred to the description above.

[0077] Using the above method, the actual heat distribution within the via area surrounding the via center can determine the anomalies within the via of the dielectric substrate under test. This allows for relatively accurate identification of any anomalies present within the via, resulting in highly targeted and precise detection. Furthermore, this method can also determine the overall anomalies of the dielectric substrate under test by analyzing the actual heat distribution within the heat conduction area surrounding the via center. This method can detect not only anomalies within the vias but also anomalies in the surface conductive layer, thus offering a wider detection range and more comprehensive detection.

[0078] According to another aspect of the present invention, a microelectronic dielectric substrate inspection device is also provided. (See also...) Figure 6 The 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:

[0079] The heating calibration module 610 is used to heat the first surface of the detection area of ​​the normal dielectric board at a preset heating station. In the 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 detection area reaches an overheated state, a first thermal image is captured facing the second surface of the detection area. When the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as preset heating parameters.

[0080] The detection module 620 is used to perform the following detection steps on the detection area of ​​the medium board under test: heating the first surface of the current detection area at a preset heating station, and when the heating control parameters reach the preset heating parameters, acquiring a second thermal image of the second surface facing the current detection area, and determining whether there is an abnormality in the medium board under test based on the actual heat distribution of the target area around the via center in the second thermal image.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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, The dielectric substrate has vias formed, including: Heating calibration steps: The first surface of the detection area of ​​the normal dielectric board is heated at a preset heating station. Within the detection area, heat can be conducted through the first surface conductive layer of the first surface and the inner wall conductive layer on 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 detection area reaches an overheated state, a first thermal image is captured facing the second surface of the detection area. When the heat distribution in the target area around the via center in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as preset heating parameters. The following detection steps are performed on the detection area of ​​the substrate under test: the first surface of the current detection area is heated at the preset heating station, and when the heating control parameter reaches the preset heating parameter, a second thermal image is captured facing the second surface of the current detection area, and the presence of any abnormality in the substrate under test is determined based on the actual heat distribution of the target area around the via center in the second thermal image.

2. The method according to claim 1, characterized in that, The heating calibration step further includes: when the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, calibrating the heat distribution in the target area at this time as a standard heat distribution. The step of determining whether the dielectric substrate under test has any abnormalities based on the actual heat distribution of the target area around the via center in the second thermal image includes: Based on the actual heat distribution of the target area around the via center in the second thermal image and the standard heat distribution, it is determined whether the dielectric substrate under test has any abnormalities.

3. The method according to claim 1, characterized in that, The heating calibration step specifically includes: While maintaining heating, the first thermal image is captured towards the second surface of the detection area located at the preset heating station. When the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as the first preset heating parameters. The detection steps specifically include: When the heating control parameters reach the first preset heating parameters, the second thermal image is captured on the second surface of the current detection area located at the preset heating station while maintaining heating.

4. The method according to claim 3, characterized in that, The target area includes a via area and a heat conduction area; the heat conduction area is a conductive area on the second surface conductive layer surrounding the via area; The heating calibration step specifically includes: When the heat distribution in the via area and / or heat conduction area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as the first preset heating parameters. The detection steps specifically include: When the heating control parameters reach the first preset heating parameters, the second thermal image is captured on the second surface of the current detection area located at the preset heating station while maintaining heating. Based on the actual heat distribution of the via area around the via center in the second thermal image and the actual heat distribution of the heat conduction area around the via center in the second thermal image, it is comprehensively determined whether the medium plate under test is abnormal.

5. The method according to claim 3, characterized in that, The target area includes a via area and a heat conduction area; the heat conduction area is a conductive area on the second surface conductive layer surrounding the via area; The calibration step specifically includes: When the heat distribution in the via area and heat conduction area around the via center in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at the two times are sequentially calibrated as the first preset heating parameters. The detection steps specifically include: When the heating control parameters sequentially reach the first preset heating parameters corresponding to the via region and the heat conduction region, a second thermal image is captured on the second surface of the current detection area located at the preset heating station while maintaining heating. Based on the actual heat distribution of the via region around the center of the via in the second thermal image captured corresponding to the via region, and based on the actual heat distribution of the heat conduction region around the center of the via in the second thermal image captured corresponding to the heat conduction region, it is comprehensively determined whether the medium plate under test is abnormal.

6. The method according to claim 1, characterized in that, The target area includes a heat conduction area; the heat conduction area is a conductive area on the second surface conductive layer surrounding the via area; The heating calibration step specifically includes: Under the premise of stopping heating, the first thermal image is captured towards the second surface of the detection area located at the preset heating station, and when the heat distribution in the heat conduction area around the center of the through hole in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as the second preset heating parameters. The detection steps specifically include: When the heating control parameters reach the second preset heating parameters, the second thermal image is captured on the second surface of the current detection area located at the preset heating station, without stopping the heating.

7. The method according to claim 1, characterized in that, The target area includes a heat conduction area; the heat conduction area is a conductive area on the second surface conductive layer surrounding the via area; The heating calibration step specifically includes: Move the detection area to the detection station, capture the first thermal image of the detection area facing the second surface of the detection area located at the detection station, and when the heat distribution in the heat conduction area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, calibrate the heating control parameters at this time as the third preset heating parameters. The detection steps specifically include: When the heating control parameters reach the third preset heating parameters, the current detection area is moved to the detection station, and the second thermal image is captured by taking pictures of the second surface of the current detection area located at the detection station.

8. The method according to any one of claims 4-7, characterized in that, The heat conduction regions corresponding to two adjacent vias of the medium plate under test are independent of each other.

9. The method according to any one of claims 1-7, 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.

10. The method according to any one of claims 1-7, characterized in that, The via is a through-silicon via or a glass via.

11. A microelectronic dielectric substrate testing device, characterized in that, The dielectric substrate has vias formed, including: The heating calibration module is used to heat the first surface of the detection area of ​​a normal dielectric board at a preset heating station. In the 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 detection area reaches an overheated state, a first thermal image is captured facing the second surface of the detection area. When the heat distribution in the target area around the center of the via in the first thermal image meets the corresponding target heat distribution requirements, the heating control parameters at this time are calibrated as preset heating parameters. The detection module is used to perform the following detection steps on the detection area of ​​the substrate under test: heating the first surface of the current detection area at the preset heating station, and when the heating control parameters reach the preset heating parameters, acquiring a second thermal image of the second surface facing the current detection area, and determining whether there is an abnormality in the substrate under test based on the actual heat distribution of the target area around the via center in the second thermal image.

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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