Method, device and equipment for measuring thickness of dielectric layer of PCB (Printed Circuit Board) and dielectric

Abstract

The invention discloses a PCB dielectric layer thickness measurement method, apparatus and device, and a medium. The method comprises the following steps: obtaining a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in the PCB to be detected; obtaining a second thickness value of the sample dielectric layer measured based on slice analysis; wherein the sample dielectric layer is a dielectric layer in a sample PCB, and the sample PCB is a PCB which has the same structure as a to-be-detected PCB and is manufactured based on the same process condition; according to the first thickness value and the second thickness value, obtaining a measurement thickness value of the target dielectric layer; wherein the measured thickness value is the average value of the first thickness value and the second thickness value, and the method has the advantages that the measurement precision is improved, and the non-destructive measurement of the to-be-detected PCB can be realized.

Description

Technical Field

[0001] The present application relates to the technical field of PCB board processing monitoring, and in particular to a method, device, equipment and medium for measuring the thickness of a dielectric layer of a PCB board. Background Art

[0002] As the signal transmission rate of high-speed multi-layer PCBs in the industry gradually increases, the requirements for transmission signal stability are gradually increasing. In the manufacturing of high-speed multi-layer PCBs, poor impedance control can easily cause loss, attenuation distortion, and signal clutter during high-speed signal transmission and at the terminal. The thickness of the dielectric layer is one of the main factors affecting impedance, so the thickness of the dielectric layer between PCB layers must be strictly controlled to improve the impedance stability of the PCB.

[0003] The thickness of the PCB dielectric layer cannot be adjusted effectively and accurately during the lamination process. Currently, the thickness of the PCB dielectric layer after lamination is mainly measured by destructive methods such as slicing. This measurement method is very one-sided and has low accuracy. Directly slicing the PCB board is likely to cause product scrapping. Summary of the invention

[0004] The main purpose of this application is to provide a method, device, equipment and medium for measuring the thickness of a PCB dielectric layer, aiming to solve the technical problem of low accuracy of existing PCB dielectric layer thickness measurement methods.

[0005] To achieve the above object, the present application provides a method for measuring the thickness of a dielectric layer of a PCB board, comprising the following steps: Obtaining a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in a PCB board to be tested; Obtaining a second thickness value of the sample dielectric layer measured based on the slice analysis; wherein the sample dielectric layer is a dielectric layer in a sample PCB board, and the sample PCB board is a PCB board having the same structure as the PCB board to be tested and manufactured based on the same process conditions; According to the first thickness value and the second thickness value, a measured thickness value of the target dielectric layer is obtained; wherein the measured thickness value is an average value of the first thickness value and the second thickness value.

[0006] Optionally, obtaining a second thickness value of the sample medium layer measured based on the slice analysis includes: Obtaining the slice information of the sample PCB board to obtain the slice thickness value of the sample dielectric layer; Obtain a depth image after drilling at a target position of the sample PCB board, and obtain a predicted thickness value of the sample dielectric layer according to the depth image; wherein the depth of the drilling hole needs to penetrate the sample dielectric layer, and the target position is the position where the thickness uniformity of the sample dielectric layer is concentrated; According to the slice thickness value and the predicted thickness value, a second thickness value of the sample medium layer is obtained; wherein the second thickness value is an average value of the slice thickness value and the predicted thickness value.

[0007] Optionally, obtaining slice information of a sample PCB board to obtain a slice thickness value of a sample dielectric layer includes: Acquire first slice information after slicing the first side surface of the sample PCB board; Acquire a first average thickness of the sample medium layer located on the first side according to the first slice information; Acquire second slicing information after slicing the second side surface of the sample PCB board; wherein the second side surface is a side surface of the sample PCB board adjacent to the first side surface; According to the second slice information, obtaining a second average thickness of the sample medium layer located on the second side; According to the first average thickness value and the second average thickness value, a slice thickness value of the sample medium layer is obtained; wherein the slice thickness value is an average value of the first average thickness value and the second average thickness value.

[0008] Optionally, a depth image is obtained after drilling at a target position of the sample PCB board, and a predicted thickness value of the sample dielectric layer is obtained according to the depth image, including: Acquire a first depth image after drilling a hole at a target position of the sample PCB board for the first time; wherein the first drilling only drills through the upper substrate, and the upper substrate is a plate material disposed on the top surface of the sample dielectric layer; According to the first depth image, obtaining a first drilling depth h1; Acquire a second depth image after drilling a hole at a target position of the sample PCB board for the second time; wherein the second drilling penetrates the sample dielectric layer; According to the second depth image, obtaining a second drilling depth h2; Obtain the predicted thickness value H of the sample dielectric layer; wherein H=h2-h1.

[0009] Optionally, the method for determining the target position includes: Acquire a first position point in the sample medium layer located on the first side; wherein the thickness of the sample medium layer at the first position point is closest to the first thickness average value; Acquire a second position point in the sample medium layer located on the second side; wherein the thickness of the sample medium layer at the second position point is closest to the second thickness average value; A first extension line is constructed into the sample medium layer from the first position point as a starting point, and a second extension line is constructed into the sample medium layer from the second position point as a starting point; wherein the first extension line is parallel to the length direction of the second side surface, and the second extension line is parallel to the length direction of the first side surface; Obtaining an intersection point of the first extension line and the second extension line in the sample medium layer; A vertical line is constructed upwards from the intersection point, and the intersection of the vertical line and the upper substrate is used as the target position.

[0010] Optionally, after obtaining the second thickness value of the sample medium layer measured based on the slice analysis, the method further includes: Obtaining a thickness difference between the second thickness value and the first thickness value; Determine whether the thickness difference is less than a preset theoretical difference; If yes, proceed to the next step; if no, return to obtaining the first thickness value of the target dielectric layer measured based on the capacitance test method.

[0011] Optionally, the capacitance test method includes: Select two capacitor plates of corresponding size and determine the effective area S of the two capacitor plates facing each other to form a parallel plate capacitor; Obtain the dielectric constant ε of the PCB board to be tested after pressing; Test the PCB to be tested by using a parallel plate capacitor to obtain the test capacitance C; According to the detected capacitance C, a first thickness value d is obtained, wherein d=εS / C.

[0012] To achieve the above purpose, the present application also provides a PCB dielectric layer thickness measurement device, comprising: A first acquisition module is used to acquire a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in a PCB board to be tested; A second acquisition module is used to obtain a second thickness value of the sample dielectric layer measured based on the slice analysis; wherein the sample dielectric layer is a dielectric layer in a sample PCB board, and the sample PCB board is a PCB board having the same structure as the PCB board to be tested and manufactured based on the same process conditions; The third acquisition module is used to acquire a measured thickness value of the target dielectric layer according to the first thickness value and the second thickness value; wherein the measured thickness value is an average value of the first thickness value and the second thickness value.

[0013] To achieve the above objectives, the present application also provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the above method.

[0014] To achieve the above objectives, the present application also provides a computer-readable storage medium, on which a computer program is stored, and a processor executes the computer program to implement the above method.

[0015] The beneficial effects that this application can achieve are as follows: The present application can measure the first thickness value of the target dielectric layer in the PCB board to be tested by the capacitance test method. However, considering the risk that data distortion and large measurement error may occur if only relying on the capacitance test method, the second thickness value of the sample dielectric layer in the sample PCB board is also measured based on the slice analysis, and the average value of the first thickness value and the second thickness value is output as the measured thickness value. Since the sample PCB board is a PCB board with the same structure as the PCB board to be tested and manufactured based on the same process conditions, the test result based on the sample PCB board can represent the thickness measurement of the target dielectric layer in the PCB board to be tested. At the same time, the average value of the thickness values ​​obtained by combining the two different test methods can accurately characterize the measured thickness of the target dielectric layer in the PCB board to be tested, thereby overcoming the disadvantage of data distortion caused by unilateral test results. At the same time, the sample PCB board is used for slice analysis and measurement, and there is no need to slice the PCB board to be tested, thereby realizing non-destructive measurement of the PCB board to be tested, avoiding product scrapping, and ensuring measurement accuracy at the same time, killing two birds with one stone, and meeting the current high-precision and high-demand measurement needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the prior art description. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0017] Figure 1 A schematic diagram of a process for measuring the thickness of a dielectric layer of a PCB board in an embodiment of the present application; Figure 2 It is a schematic diagram of the principle of calculating the predicted thickness value of the sample dielectric layer based on two drillings on the sample PCB board in an embodiment of the present application; Figure 3 It is a schematic diagram of the principle of determining the target position on the sample PCB board in the embodiment of the present application.

[0018] Reference numerals: 110 - sample medium layer, 120 - upper substrate, 130 - lower substrate, 140 - first side, 150 - second side, 160 - first position point, 170 - second position point, 180 - first extension line, 190 - second extension line, 210 - vertical line, 220 - target position.

[0019] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0022] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0023] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by this application. Example 1

[0024] Reference Figure 1-Figure 3 This embodiment provides a method for measuring the thickness of a dielectric layer of a PCB, comprising the following steps: Obtaining a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in a PCB board to be tested; Obtaining a second thickness value of the sample dielectric layer 110 measured based on the slice analysis; wherein the sample dielectric layer 110 is a dielectric layer in a sample PCB board, and the sample PCB board is a PCB board having the same structure as the PCB board to be tested and manufactured based on the same process conditions; According to the first thickness value and the second thickness value, a measured thickness value of the target dielectric layer is obtained; wherein the measured thickness value is an average value of the first thickness value and the second thickness value.

[0025] In the present embodiment, the first thickness value of the target dielectric layer in the PCB board to be tested can be measured by the capacitance test method. However, considering the risk that data distortion and large measurement error may be caused by relying solely on the capacitance test method, the second thickness value of the sample dielectric layer 110 in the sample PCB board is also measured based on the slice analysis, and the average value of the first thickness value and the second thickness value is output as the measured thickness value. Since the sample PCB board is a PCB board with the same structure as the PCB board to be tested and manufactured based on the same process conditions, the test result based on the sample PCB board can represent the thickness measurement of the target dielectric layer in the PCB board to be tested. At the same time, the average value of the thickness values ​​obtained by combining the two different test methods can accurately represent the measured thickness of the target dielectric layer in the PCB board to be tested, thereby overcoming the disadvantage of data distortion caused by unilateral test results. At the same time, the sample PCB board is used for slice analysis and measurement, and there is no need to slice the PCB board to be tested, thereby realizing non-destructive measurement of the PCB board to be tested, avoiding product scrapping, and ensuring measurement accuracy at the same time, killing two birds with one stone, and meeting the current high-precision and high-demand measurement needs.

[0026] It should be noted that the basic structures of the PCB board to be tested and the sample PCB board both include a dielectric layer, and an upper substrate 120 and a lower substrate 130 respectively connected to the top and bottom surfaces of the dielectric layer, and the dielectric layer in the middle is the object layer to be measured.

[0027] As an optional implementation manner, obtaining a second thickness value of the sample medium layer 110 measured based on slice analysis includes: Acquire the slice information of the sample PCB board to obtain the slice thickness value of the sample dielectric layer 110; Obtain a depth image after drilling at the target position 220 of the sample PCB board, and obtain a predicted thickness value of the sample dielectric layer 110 according to the depth image; wherein the depth of the drilling hole needs to penetrate the sample dielectric layer 110, and the target position is the position where the thickness uniformity of the sample dielectric layer 110 is concentrated; According to the slice thickness value and the predicted thickness value, a second thickness value of the sample medium layer 110 is obtained; wherein the second thickness value is an average value of the slice thickness value and the predicted thickness value.

[0028] In this embodiment, when calculating the second thickness value of the sample dielectric layer 110, the measurement error is also taken into account. Here, the slice thickness value of the sample dielectric layer 110 is first obtained through the slice information of the sample PCB board, and then a depth image can be collected after drilling a hole at the target position 220 of the sample PCB board. Since the target position is the position where the thickness uniformity of the sample dielectric layer 110 is concentrated, the depth image after drilling the hole at the target position 220 not only reflects the drilling depth, but also reflects the uniform thickness of the sample dielectric layer 110 from the side, that is, the predicted thickness value, to avoid the situation where the thickness data measured by drilling holes at random positions of the sample dielectric layer 110 with uneven thickness is too large or too small, further improving the data accuracy, and finally outputting the average value of the slice thickness value and the predicted thickness value as the second thickness value. Therefore, this embodiment simultaneously characterizes the thickness of the sample dielectric layer 110 from two dimensions: sample PCB board slice measurement and depth image measurement, which can reduce the risk of large errors caused by a single measurement and further improve the measurement accuracy.

[0029] As an optional implementation, obtaining the slice information of the sample PCB board to obtain the slice thickness value of the sample dielectric layer 110 includes: Acquire first slice information after slicing the first side surface 140 of the sample PCB board; According to the first slice information, a first average thickness of the sample medium layer 110 located on the first side 140 is obtained; Acquire second slicing information after slicing the second side surface 150 of the sample PCB board; wherein the second side surface 150 is a side surface of the sample PCB board adjacent to the first side surface 140; According to the second slice information, a second average thickness of the sample medium layer 110 located on the second side 150 is obtained; According to the first average thickness value and the second average thickness value, a slice thickness value of the sample medium layer 110 is obtained; wherein the slice thickness value is an average value of the first average thickness value and the second average thickness value.

[0030] In this embodiment, when calculating the slice thickness value, since there may be a situation where the thickness of the sample dielectric layer 110 is uneven, in order to improve the measurement accuracy, slice measurements are performed from the first side surface 140 and the second side surface 150 adjacent to the sample PCB board, and the first slice information and the second slice information are obtained respectively, thereby obtaining the first thickness average value and the second thickness average value respectively, and finally the average value of the first thickness average value and the second thickness average value is output as the slice thickness value of the sample dielectric layer 110. The slice thickness value finally obtained can accurately and effectively characterize the thickness distribution of the sample dielectric layer 110, thereby providing accurate measurement data to further improve the accuracy of the final measurement result.

[0031] It should be noted that when calculating the first thickness average value and the second thickness average value, multiple measurement points can be selected from the sample medium layer 110 on the corresponding side, the thickness of the sample medium layer 110 corresponding to the position of each measurement point is calculated, and then the average value of the multiple thickness data is output as the thickness average value of the corresponding side.

[0032] As an optional implementation, a depth image is obtained after drilling at the target position 220 of the sample PCB board, and a predicted thickness value of the sample dielectric layer 110 is obtained according to the depth image, including: Acquire a first depth image after the first drilling at the target position 220 of the sample PCB board; wherein the first drilling only drills through the upper substrate 120, and the upper substrate 120 is a plate material disposed on the top surface of the sample dielectric layer 110; According to the first depth image, obtaining a first drilling depth h1; Acquire a second depth image after drilling a hole for the second time at the target position 220 of the sample PCB board; wherein the second drilling penetrates the sample dielectric layer 110; According to the second depth image, obtaining a second drilling depth h2; The predicted thickness value H of the sample medium layer 110 is obtained, wherein H=h2-h1.

[0033] In the present embodiment, when calculating the predicted thickness value, a first hole is drilled at the target position 220 of the sample PCB board. Since the first hole is drilled only through the upper substrate 120, the corresponding hole depth data (i.e., the first drilling depth h1) can be measured based on the first depth image of the sample PCB board after the first hole is obtained. The first drilling depth h1 is the thickness of the upper substrate 120. Then, the second hole is drilled based on the same target position 220. At this time, only the sample dielectric layer 110 is drilled through, and the second depth image with drilling depth information can be obtained. The second drilling depth h2 can be obtained, and h2 is the total thickness of the sample dielectric layer 110 and the upper substrate 120. Therefore, based on the depth image information after the two holes are drilled, the first drilling depth h1 and the second drilling depth h2 can be accurately obtained. The difference between the two is the predicted thickness value H of the sample dielectric layer 110, which is more accurate and effective than physical measurement, and further improves the accuracy of the measurement data.

[0034] As an optional implementation, the method for determining the target position 220 includes: Acquire a first position point 160 in the sample medium layer 110 located at the first side 140 ; ​​wherein the thickness of the sample medium layer 110 at the first position point 160 is closest to the first average thickness; Acquire a second position point 170 in the sample medium layer 110 located at the second side 150; wherein the thickness of the sample medium layer 110 at the second position point 170 is closest to the second thickness average value; A first extension line 180 is constructed from the first position point 160 into the sample medium layer 110 , and a second extension line 190 is constructed from the second position point 170 into the sample medium layer 110 ; wherein the first extension line 180 is parallel to the length direction of the second side surface 150 , and the second extension line 190 is parallel to the length direction of the first side surface 140 ; Obtaining the intersection of the first extension line 180 and the second extension line 190 in the sample medium layer 110; A vertical line 210 is constructed upwards from the intersection point, and the intersection point of the vertical line 210 and the upper substrate 120 is used as the target position 220 .

[0035] In this embodiment, the positions closest to the first average thickness and the second average thickness can be found in the sample medium layer 110 on the first side 140 and the second side 150, and marked as the first position point 160 and the second position point 170, respectively. Then, based on the first position point 160 and the second position point 170, the sample medium layer 110 is extended to obtain an intersection point, which is a position in the sample medium layer 110 that is closer to its uniform thickness. Therefore, a vertical line 210 is constructed upwards with the intersection point as the starting point, and the intersection of the vertical line 210 and the upper substrate 120 can be used as a more ideal target position 220, which provides a prerequisite for the subsequent measurement of an accurate predicted thickness value.

[0036] It should be noted that when searching for the first position point 160, a plurality of evenly spaced measurement points can be selected on the first side 140 to obtain thickness sample data of the sample medium layer 110 corresponding to the plurality of measurement points, respectively. The average of the plurality of thickness sample data is the first thickness average value. The measurement point corresponding to the thickness sample data closest to the first thickness average value is selected as the target measurement point. Then, a plurality of alternative measurement points are selected on both sides of the target measurement point, and the positions of the alternative measurement points do not exceed the adjacent measurement points. The thickness sample data of the sample medium layer 110 corresponding to the alternative measurement points are obtained. Then, the point whose corresponding thickness sample data is closest to the first thickness average value is screened out again from the target measurement point and the alternative measurement points, and the point is used as the final first position point 160. Similarly, the method for searching for the second position point 170 is the same. For example, five evenly spaced measurement points are selected on the first side 140 to measure thickness data a, b, c, d, and e respectively, so that the first thickness average value m is (a+b+c+d+e) / 5. Then, the point whose corresponding thickness sample data is closest to the first thickness average value m among a, b, c, d, and e is selected. Here, measurement point b is taken as an example. Then, multiple candidate measurement points b1, b2, b3...bn are selected on both sides of measurement point b, and the candidate measurement points are between measurement points a and c. The thickness sample data of the sample medium layer 110 corresponding to the candidate measurement points b1, b2, b3...bn are obtained, and the point closest to the first thickness average value is screened out again, such as the candidate measurement point b2, and b2 is marked as the first position point 160.

[0037] In other embodiments, the method of constructing a reference coordinate system can also be used to determine the target position 220. First, the simulation point cloud data of the sample PCB board is obtained, and a reference coordinate system is constructed with the geometric center of the sample PCB board as the origin. The coordinate information of the first position point 160 and the second position point 170 in the reference coordinate system is obtained, and the coordinate information of the target position 220 can be determined, and the identification is accurate and efficient.

[0038] As an optional implementation, after obtaining the second thickness value of the sample medium layer 110 measured based on the slice analysis, the method further includes: Obtaining a thickness difference between the second thickness value and the first thickness value; Determine whether the thickness difference is less than a preset theoretical difference; If yes, proceed to the next step; if no, return to obtaining the first thickness value of the target dielectric layer measured based on the capacitance test method.

[0039] In this embodiment, after the first thickness value and the second thickness value are measured respectively, there may be a situation where the error of one of the measurement results is too large. Under normal circumstances, the two measurement results should not be much different. Therefore, the data authenticity of the first thickness value and the second thickness value is further detected here, that is, the thickness difference between the second thickness value and the first thickness value is compared with a preset theoretical difference. The theoretical difference is the difference between the two measurement results within the normal error range. If the thickness difference is less than the theoretical difference, it means that the data of the two measurement results are normal and the next step can be entered. If not, it means that the data of one of the measurement results is distorted (the situation where the data of both measurement results are distorted is extremely rare and is not considered for the time being). At this time, the measurements are performed again to further ensure the authenticity and validity of the measurement result data to ensure the measurement accuracy.

[0040] As an optional implementation, the capacitance test method includes: Select two capacitor plates of corresponding size and determine the effective area S of the two capacitor plates facing each other to form a parallel plate capacitor; Obtain the dielectric constant ε of the PCB board to be tested after pressing; Test the PCB to be tested by using a parallel plate capacitor to obtain the test capacitance C; According to the detected capacitance C, a first thickness value d is obtained, wherein d=εS / C.

[0041] In this embodiment, when performing a capacitance test, two capacitor plates of corresponding sizes are selected according to the test requirements, and the effective area S facing the two capacitor plates can be determined at the same time. At the same time, the dielectric constant ε of the PCB board to be tested after pressing can be obtained (which can be obtained by consulting the relevant technical manual). When the parallel plate capacitor formed by the two capacitor plates is used to test the PCB board to be tested, the detection capacitance C can be obtained, and the expression of the detection capacitance C is: C=εS / d, and the first thickness value d=εS / C can be derived. Here, after multiple tests, the data with obvious distortion of the test results can be eliminated, and the average value of the remaining test data is used as the first thickness value d, so as to achieve non-destructive measurement, and the measurement data is accurate and effective. Example 2

[0042] Reference Figure 1-Figure 3 Based on the same inventive concept as the above-mentioned embodiment, this embodiment further provides a PCB dielectric layer thickness measuring device, comprising: A first acquisition module is used to acquire a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in a PCB board to be tested; A second acquisition module is used to acquire a second thickness value of the sample dielectric layer 110 measured based on the slice analysis; wherein the sample dielectric layer 110 is a dielectric layer in a sample PCB board, and the sample PCB board is a PCB board having the same structure as the PCB board to be tested and manufactured based on the same process conditions; The third acquisition module is used to acquire a measured thickness value of the target dielectric layer according to the first thickness value and the second thickness value; wherein the measured thickness value is an average value of the first thickness value and the second thickness value.

[0043] The relevant explanations and examples of each module in the device of this embodiment can refer to the method of the aforementioned embodiment, and will not be repeated here. Example 3

[0044] Based on the same inventive concept as the above-mentioned embodiment, this embodiment provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the above-mentioned method. Example 4

[0045] Based on the same inventive concept as the aforementioned embodiment, this embodiment provides a computer-readable storage medium, on which a computer program is stored, and a processor executes the computer program to implement the aforementioned method.

[0046] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for measuring the thickness of a dielectric layer of a PCB, characterized in that: The following steps are involved: Obtaining a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in a PCB board to be tested; Acquire a second thickness value of the sample dielectric layer measured based on the slice analysis; wherein the sample dielectric layer is a dielectric layer in a sample PCB board, and the sample PCB board is a PCB board having the same structure as the PCB board to be tested and manufactured based on the same process conditions; A measured thickness value of the target dielectric layer is acquired according to the first thickness value and the second thickness value; wherein the measured thickness value is an average value of the first thickness value and the second thickness value.

2. A method for measuring the thickness of a PCB dielectric layer as claimed in claim 1, characterized in that: The step of obtaining a second thickness value of the sample medium layer measured based on the slice analysis includes: Obtaining the slice information of the sample PCB board to obtain the slice thickness value of the sample dielectric layer; Obtaining a depth image after drilling a hole at a target position of the sample PCB board, and obtaining a predicted thickness value of the sample dielectric layer according to the depth image; wherein the depth of the drilling hole needs to penetrate the sample dielectric layer, and the target position is a position where the thickness uniformity of the sample dielectric layer is concentrated; According to the slice thickness value and the predicted thickness value, a second thickness value of the sample medium layer is acquired; wherein the second thickness value is an average value of the slice thickness value and the predicted thickness value.

3. A method for measuring the thickness of a PCB dielectric layer as claimed in claim 2, characterized in that: The step of obtaining the slice information of the sample PCB board to obtain the slice thickness value of the sample dielectric layer includes: Acquire first slice information after slicing the first side surface of the sample PCB board; Acquire a first average thickness of the sample medium layer located on the first side according to the first slice information; Acquire second slicing information after slicing the second side surface of the sample PCB board; wherein the second side surface is a side surface of the sample PCB board adjacent to the first side surface; Acquire a second average thickness of the sample medium layer located on the second side according to the second slice information; According to the first average thickness value and the second average thickness value, a slice thickness value of the sample medium layer is obtained; wherein the slice thickness value is an average value of the first average thickness value and the second average thickness value.

4. A method for measuring the thickness of a dielectric layer of a PCB board as claimed in claim 3, characterized in that: The step of acquiring a depth image after drilling a hole at a target position of the sample PCB board, and acquiring a predicted thickness value of the sample dielectric layer according to the depth image, comprises: Acquire a first depth image after drilling a hole at a target position of the sample PCB board for the first time; wherein the first drilling only drills through an upper substrate, and the upper substrate is a plate material disposed on a top surface of the sample dielectric layer; Acquire a first drilling depth h1 according to the first depth image; Acquire a second depth image after drilling a hole at a target position of the sample PCB board for the second time; wherein the second drilling penetrates the sample dielectric layer; According to the second depth image, obtaining a second drilling depth h2; Obtain a predicted thickness value H of the sample medium layer; wherein H=h2-h1.

5. A method for measuring the thickness of a dielectric layer of a PCB board as claimed in claim 4, characterized in that: The method for determining the target position includes: Acquire a first position point in the sample medium layer located on the first side; wherein the thickness of the sample medium layer at the first position point is closest to the first thickness average value; Acquire a second position point in the sample medium layer located on the second side; wherein the thickness of the sample medium layer at the second position point is closest to the second thickness average value; A first extension line is constructed into the sample medium layer from the first position point as a starting point, and a second extension line is constructed into the sample medium layer from the second position point as a starting point; wherein the first extension line is parallel to the length direction of the second side surface, and the second extension line is parallel to the length direction of the first side surface; Acquire an intersection point of the first extension line and the second extension line in the sample medium layer; A vertical line is constructed upwards with the intersection point as a starting point, and an intersection point between the vertical line and the upper substrate is used as the target position.

6. A method for measuring the thickness of a dielectric layer of a PCB board as claimed in any one of claims 1 to 5, characterized in that: After obtaining the second thickness value of the sample medium layer measured based on the slice analysis, the method further includes: Obtaining a thickness difference between the second thickness value and the first thickness value; Determining whether the thickness difference is less than a preset theoretical difference; If yes, proceed to the next step; if no, return to the step of obtaining the first thickness value of the target dielectric layer measured based on the capacitance test method.

7. A method for measuring the thickness of a dielectric layer of a PCB board as claimed in claim 1, characterized in that: The capacitance test method includes: Select two capacitor plates of corresponding sizes and determine the effective area S that the two capacitor plates face each other to form a parallel plate capacitor; Obtain the dielectric constant ε of the PCB board to be tested after pressing; Testing the PCB board to be tested by the parallel plate capacitor to obtain a testing capacitance C; According to the detection capacitance C, a first thickness value d is obtained, wherein d=εS / C.

8. A device for measuring the thickness of a dielectric layer of a PCB, characterized in that: include: A first acquisition module is used to acquire a first thickness value of a target dielectric layer measured based on a capacitance test method; wherein the target dielectric layer is a dielectric layer in a PCB board to be tested; A second acquisition module is used to acquire a second thickness value of a sample dielectric layer measured based on slice analysis; wherein the sample dielectric layer is a dielectric layer in a sample PCB board, and the sample PCB board is a PCB board with the same structure as the PCB board to be tested and manufactured based on the same process conditions; A third acquisition module is used to acquire a measured thickness value of the target dielectric layer according to the first thickness value and the second thickness value; wherein the measured thickness value is an average value of the first thickness value and the second thickness value.

9. A computer device, characterized in that: The computer device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement a method for measuring the thickness of a dielectric layer of a PCB board as claimed in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the processor executes the computer program to implement a method for measuring the thickness of a dielectric layer of a PCB board as claimed in any one of claims 1 to 6.

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