Printed circuit board and method of drilling the same

Abstract

The application discloses a printed circuit board and a drilling method thereof. The drilling method of the printed circuit board comprises the following steps: obtaining theoretical position information of a to-be-drilled board and a target conductive layer thereof; determining a detection area and a non-detection area of the to-be-drilled board based on the theoretical position information of the target conductive layer; drilling the detection area of the to-be-drilled board based on a first sensitivity of a drilling device, and drilling the non-detection area of the to-be-drilled board based on a second sensitivity of the drilling device, so as to obtain a target through hole, and detecting actual position information of the target conductive layer in the drilling process, wherein the first sensitivity is greater than the second sensitivity; determining a depth control depth of the target through hole based on the actual position information of the target conductive layer, and drilling the target through hole based on the depth control depth, so as to prepare the printed circuit board. Through the above method, the sensitivity of the drilling device can be dynamically adjusted, the target conductive layer can be detected with high precision, and the drilling precision of the printed circuit board is improved.

Description

Technical Field

[0001] This invention relates to the technical field of drilling methods for printed circuit boards, and particularly to printed circuit boards and drilling methods thereof. Background Technology

[0002] With the continuous advancement of the information technology industry, the speed and frequency of digital signal transmission are increasing, making the integrity of signals increasingly crucial. A section of unused copper plating in a metallized via on a printed circuit board (PCB) increases signal transmission loss. Furthermore, as the frequency of circuit signals increases to a certain level, the excess copper plating in these unused vias acts like an antenna, radiating signals and interfering with other surrounding signals, potentially compromising signal integrity in severe cases.

[0003] Therefore, back-drilling is usually used to remove as much excess copper plating as possible, thereby reducing its impact on signal transmission of the metallized via plate.

[0004] Current back-drilling methods typically involve pre-setting a predetermined back-drilling depth and then back-drilling the metallized holes according to that depth to remove excess copper plating. However, in actual production, factors such as uneven board thickness can lead to insufficient drilling accuracy when back-drilling to remove residual copper at the predetermined depth. This results in significant signal loss in signal holes, making it difficult to meet the high-frequency and high-speed performance requirements of the product. Summary of the Invention

[0005] This invention provides a printed circuit board and a drilling method thereof to solve the problem of insufficient drilling accuracy in the prior art.

[0006] To address the aforementioned technical problems, this invention provides a drilling method for printed circuit boards, comprising: acquiring a board to be drilled and theoretical position information of a target conductive layer on the board; determining a detection area and a non-detection area of ​​the board to be drilled based on the theoretical position information of the target conductive layer; drilling the detection area of ​​the board to be drilled based on a first sensitivity of the drilling equipment, and drilling the non-detection area of ​​the board to be drilled based on a second sensitivity of the drilling equipment, to obtain a target via, and detecting the actual position information of the target conductive layer during the drilling process, wherein the first sensitivity is greater than the second sensitivity; determining the control depth of the target via based on the actual position information of the target conductive layer; and drilling the target via based on the control depth to fabricate a printed circuit board.

[0007] The steps of drilling a hole in the detection area of ​​the workpiece to be drilled based on the first sensitivity of the drilling equipment and drilling a hole in the non-detection area of ​​the workpiece to be drilled based on the second sensitivity of the drilling equipment to obtain a target through hole include: adjusting the voltage of the detection circuit of the drilling equipment to a first voltage to set the sensitivity of the drilling equipment to the first sensitivity, and adjusting the voltage of the detection circuit of the drilling equipment to a second voltage to set the sensitivity of the drilling equipment to the second sensitivity; wherein the first voltage is greater than the second voltage.

[0008] The target conductive layer includes a first conductive layer and a second conductive layer, wherein the first conductive layer and the second conductive layer are respectively the surface conductive layers of the plate to be drilled; the step of determining the detection area and non-detection area of ​​the plate to be drilled based on the theoretical position information of the target conductive layer includes: determining the detection area based on the area within a preset range where the theoretical position information of the first conductive layer and the second conductive layer are located; and determining other areas besides the detection area as non-detection areas.

[0009] The detection area includes a first detection area and a second detection area. The step of determining the detection area based on the preset range of the theoretical position information of the first conductive layer and the second conductive layer includes: obtaining the theoretical thickness of the plate to be drilled, and determining a preset value of the preset range based on the theoretical thickness, wherein the preset value is 1 / 2 of the preset range; adding the preset value to the theoretical position information of the first conductive layer to obtain the upper limit of the first detection area, and subtracting the preset value from the theoretical position information of the first conductive layer to determine the lower limit of the first detection area; and adding the preset value to the theoretical position information of the second conductive layer to obtain the upper limit of the second detection area, and subtracting the preset value from the theoretical position information of the second conductive layer to determine the lower limit of the second detection area.

[0010] The step of determining the control depth of the plate to be drilled based on the actual position information of the target conductive layer includes: determining the actual thickness of the plate to be drilled based on the actual position information of the first conductive layer and the second conductive layer; and determining the control depth based on the actual thickness of the plate to be drilled and the first control depth ratio.

[0011] The target conductive layer includes a first conductive layer and a reference conductive layer. The first conductive layer is the surface conductive layer of the board to be drilled, and the reference conductive layer is the inner conductive layer of the board to be drilled. The steps of determining the detection area and non-detection area of ​​the board to be drilled based on the theoretical position information of the target conductive layer include: determining the detection area based on the area within a preset range where the theoretical position information of the first conductive layer and the reference conductive layer are located; and determining other areas besides the detection area as non-detection areas.

[0012] The detection area includes a first detection area and a second detection area. The step of determining the detection area based on the preset range of the theoretical position information of the first conductive layer and the reference conductive layer includes: obtaining the theoretical thickness of the plate to be drilled, and determining a preset value of the preset range based on the theoretical thickness, wherein the preset value is 1 / 2 of the preset range; adding the preset value to the theoretical position information of the first conductive layer to obtain the upper limit of the first detection area, and subtracting the preset value from the theoretical position information of the first conductive layer to determine the lower limit of the first detection area; and adding the preset value to the theoretical position information of the reference conductive layer to obtain the upper limit of the second detection area, and subtracting the preset value from the theoretical position information of the reference conductive layer to determine the lower limit of the second detection area.

[0013] The step of determining the control depth of the plate to be drilled based on the actual position information of the target conductive layer includes: determining the distance between the first conductive layer and the reference conductive layer based on the actual position information of the first conductive layer and the actual position information of the reference conductive layer; and determining the control depth as the sum of the distance between the first conductive layer and the reference conductive layer and the control depth value of the reference conductive layer in the direction away from the first conductive layer.

[0014] The steps of drilling the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment and drilling the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole, and detecting the actual position information of the target conductive layer during the drilling process, further include: in response to drilling the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and after detecting the target conductive layer in the detection area, adjusting the drilling equipment to the second sensitivity to drill until entering the next detection area.

[0015] To solve the above-mentioned technical problems, the present invention also provides a printed circuit board, which is prepared by the drilling method of the printed circuit board described in any of the above-mentioned claims.

[0016] The beneficial effects of this invention are as follows: Unlike existing technologies, the drilling method for printed circuit boards of this invention enables the drilling equipment to improve detection accuracy by maintaining high sensitivity when the drill tip contacts the target conductive layer during the preparation of the target through-hole, thereby improving the accuracy of the detected actual position information of the target conductive layer. Conversely, when drilling non-detection areas, the drilling equipment operates in a low-sensitivity state, reducing abnormal signals generated by the contact between the drill body and various conductive layers. This reduces the impact of mixed signals on detection accuracy, further improving the detection accuracy of the drilling equipment, ultimately enhancing the precision and accuracy of depth control, improving the precision of back-drilling the target through-hole, and achieving high-precision control of the back-drilling stub. Attached Figure Description

[0017] Figure 1 This is a schematic flowchart of an embodiment of the drilling method for printed circuit boards of the present invention;

[0018] Figure 2 This is a schematic flowchart of another embodiment of the drilling method for printed circuit boards of the present invention;

[0019] Figure 3 yes Figure 2 A schematic diagram of one implementation method for determining the detection area in the example;

[0020] Figure 4 This is a flowchart illustrating another embodiment of the drilling method for printed circuit boards according to the present invention;

[0021] Figure 5 yes Figure 4 A schematic diagram illustrating another implementation method for determining the detection area in the embodiment;

[0022] Figure 6 This is a schematic diagram of the structure of a printed circuit board according to an embodiment of the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0025] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0026] Please see Figure 1 , Figure 1This is a flowchart illustrating an embodiment of the drilling method for printed circuit boards according to the present invention.

[0027] Step S11: Obtain the theoretical location information of the plate to be drilled and the target conductive layer of the plate to be drilled.

[0028] The plate to be drilled is obtained, and the theoretical location information of the target conductive layer of the plate to be drilled is obtained.

[0029] The theoretical location information of the target conductive layer of the board to be drilled can be obtained based on the design drawings of the board to be drilled, or based on the thickness of each sub-board layer before lamination, or based on the residual copper ratio of the board to be drilled. The specific method for obtaining the theoretical location information of the target conductive layer of the board to be drilled is not limited here.

[0030] The theoretical position information of the target conductive layer of the plate to be drilled may include fixed position information such as the coordinate information of the target conductive layer, the position information of the target conductive layer relative to the drilling equipment, or the position information of the target conductive layer relative to the preset drill tip position of the drilling equipment. The specific details are not limited here.

[0031] Step S12: Determine the detection area and non-detection area of ​​the plate to be drilled based on the theoretical location information of the target conductive layer.

[0032] After obtaining the theoretical location information of the target conductive layer of the plate to be drilled, the detection area and non-detection area of ​​the plate to be drilled are determined based on the theoretical location information of the target conductive layer.

[0033] The detection area is the region within a certain range where the target conductive layer is located, determined based on the theoretical location information of the target conductive layer, while the non-detection area is any other region besides the detection area.

[0034] Step S13: Drill holes in the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and drill holes in the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole, and detect the actual position information of the target conductive layer during the drilling process, wherein the first sensitivity is greater than the second sensitivity.

[0035] After determining the detection area and the non-detection area, drilling is performed on the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and on the non-detection area based on the second sensitivity of the drilling equipment, to obtain the target through-hole. During the drilling process, the actual location information of the target conductive layer is detected. The detection area and the non-detection area are regions on the side of the board to be drilled, and the target through-hole penetrates both the detection area and the non-detection area.

[0036] Since the first sensitivity is greater than the second sensitivity, the drilling equipment operates in a high-sensitivity state when drilling in the detection area. This high sensitivity allows the drill tip to improve detection accuracy when contacting the target conductive layer, thereby enhancing the accuracy of the detected actual location information of the target conductive layer. Conversely, the drilling equipment operates in a low-sensitivity state when drilling in non-detection areas. This reduces abnormal signals generated by the drill body contacting various conductive layers, thus minimizing the impact of stray signals on detection accuracy and further improving the overall detection precision.

[0037] Step S14: Determine the depth control of the target via based on the actual location information of the target conductive layer.

[0038] After obtaining the actual location information of the target conductive layer, the control depth of the target via is determined based on the actual location information of the target conductive layer.

[0039] In one specific implementation, the deviation between the controlled depth and the theoretical controlled depth of the target via can be determined by the deviation between the actual position information of the target conductive layer and the theoretical position information of the target conductive layer, thereby determining the controlled depth of the target via.

[0040] In another specific implementation, the depth of the target via can also be determined based on the correspondence between the target conductive layer and the depth control, using the aforementioned correspondence and the actual position information of the target conductive layer. Specifically, the method for determining the depth of control can be set based on the specific position of the target conductive layer or the actual application, and is not limited here.

[0041] Step S15: Drill the target through hole based on the controlled depth to prepare the printed circuit board.

[0042] After obtaining the depth of control, the target through hole is drilled based on the depth of control, thereby back-drilling the target through hole to prepare the printed circuit board.

[0043] Through the above steps, the drilling method for printed circuit boards in this embodiment first determines the detection area and non-detection area of ​​the board to be drilled based on the theoretical position information of the target conductive layer. Then, based on the first sensitivity of the drilling equipment, drilling is performed on the detection area of ​​the board to be drilled, and based on the second sensitivity of the drilling equipment, drilling is performed on the non-detection area of ​​the board to be drilled to obtain the target through hole. During the drilling process, the actual position information of the target conductive layer is detected, wherein the first sensitivity is greater than the second sensitivity. Finally, the control depth of the target through hole is determined based on the actual position information of the target conductive layer, and the target through hole is drilled based on the control depth to prepare the printed circuit board. In this way, during the preparation of the target through hole, the drill tip of the drilling equipment can improve the detection accuracy of the drilling equipment based on a high-sensitivity state when contacting the target conductive layer, thereby improving the accuracy of the detected actual position information of the target conductive layer. When drilling equipment is in a low-sensitivity state while drilling in non-detection areas, it can reduce abnormal signals generated by the contact between the drill body and each conductive layer, thereby reducing the impact of mixed signals on detection accuracy, further improving the detection accuracy of the drilling equipment, and ultimately improving the accuracy and precision of depth control, improving the accuracy of back drilling of target through holes, and realizing high-precision control of back drilling stubs.

[0044] In other embodiments, drilling is performed on the detection area of ​​the workpiece to be drilled based on a first sensitivity of the drilling equipment, and drilling is performed on the non-detection area of ​​the workpiece to be drilled based on a second sensitivity of the drilling equipment. The adjustment of the sensitivity in the step of obtaining the target through hole can be specifically performed through the following steps:

[0045] The voltage of the detection circuit of the drilling equipment is adjusted to a first voltage to set the sensitivity of the drilling equipment to a first sensitivity, and the voltage of the detection circuit of the drilling equipment is adjusted to a second voltage to set the sensitivity of the drilling equipment to a second sensitivity, wherein the first voltage is greater than the second voltage.

[0046] By dynamically controlling the sensitivity of the drilling equipment by adjusting the voltage of the detection circuit, the drilling equipment is in different sensitive states when drilling in the detection area and non-detection area, thereby responding to different electrical signals. This improves the contact sensitivity between the drill tip and the target conductive layer, enhances detection accuracy, and reduces abnormal signals generated by the contact between the drill body and each conductive layer. This achieves high-precision detection of the target conductive layer position and realizes high-precision control of the back drill stub.

[0047] In other embodiments, the first voltage value ranges from 22 to 26V, specifically 22V, 23V, 24V or 26V, etc., and the second voltage value ranges from 10 to 14V, specifically 10V, 11V, 12V or 14V, etc.

[0048] In other embodiments, drilling is performed on the detection area of ​​the workpiece to be drilled based on the first sensitivity of the drilling equipment. After the target conductive layer is detected in the detection area, the drilling equipment is directly adjusted to the second sensitivity to continue drilling until the next detection area is reached. This avoids the invalid setting of the first sensitivity and improves the utilization rate of production resources. In other embodiments, the sensitivity of the drilling equipment can also be adjusted based on the detection area and the non-detection area settings, and the specific settings can be made according to the actual situation.

[0049] Please see Figure 2 , Figure 2 This is a schematic flowchart of another embodiment of the drilling method for printed circuit boards of the present invention. In this embodiment, the target conductive layer includes a first conductive layer and a second conductive layer, wherein the first conductive layer and the second conductive layer are respectively the surface conductive layers of the board to be drilled, i.e., the conductive layers on opposite sides of the board to be drilled.

[0050] Step S21: Obtain the theoretical position information of the plate to be drilled and the first and second conductive layers of the plate to be drilled.

[0051] The theoretical position information of the plate to be drilled, its first conductive layer, and its second conductive layer is obtained. In this embodiment, the theoretical position information may include coordinate information.

[0052] The method for obtaining the theoretical location information of the target conductive layer in this step is the same as that in the aforementioned embodiments, please refer to the previous text, and will not be repeated here.

[0053] Step S22: Determine the detection area based on the preset range of the theoretical location information of the first conductive layer and the second conductive layer, and determine the other areas outside the detection area as non-detection areas.

[0054] After obtaining the theoretical location information of the first conductive layer and the second conductive layer, a detection area is determined based on the preset range where the theoretical location information of the first conductive layer and the second conductive layer is located, and all other areas besides the detection area are determined as non-detection areas. Since the target conductive layer is divided into a first conductive layer and a second conductive layer, the detection area in this embodiment is also divided into a first detection area and a second detection area, corresponding to include both the first and second conductive layers.

[0055] The preset range can be set based on the theoretical thickness of the plate to be drilled or set to a fixed value, such as 2 cm or 3 cm, without specific limitations. Since there may be errors between the theoretical and actual position information, setting a preset range near the theoretical position information can, to a certain extent, ensure that the first conductive layer and the second conductive layer are located within their respective detection areas, thereby improving the detection accuracy during drilling.

[0056] In one specific implementation, after obtaining the theoretical position information of the first conductive layer and the second conductive layer, the theoretical thickness of the plate to be drilled can be obtained first, and a preset value for a predetermined range can be determined based on the theoretical thickness, wherein the preset value is 1 / 2 of the preset range. The theoretical position information of the first conductive layer is added to the preset value to obtain the upper limit of the first detection area, and the theoretical position information of the first conductive layer is subtracted from the preset value to determine the lower limit of the first detection area; similarly, the theoretical position information of the second conductive layer is added to the preset value to obtain the upper limit of the second detection area, and the theoretical position information of the second conductive layer is subtracted from the preset value to determine the lower limit of the second detection area, thereby determining the specific position information of the first and second detection areas.

[0057] In one specific implementation, the step of determining the preset range value based on the theoretical thickness may include: multiplying the theoretical thickness of the plate to be drilled by a preset coefficient to obtain the preset range value. The preset coefficient may include 5% to 15%, specifically 5%, 8%, 10%, 13%, or 15%, etc., and is not limited here. In other implementations, other calculation methods may be used to determine the preset range value based on the theoretical thickness, and are not limited here.

[0058] Please see Figure 3 , Figure 3 yes Figure 2 A schematic diagram of one implementation method for determining the detection area in the example.

[0059] The plate to be drilled 100 in this embodiment includes two opposing conductive layers: a first conductive layer 101 and a second conductive layer 102. The detection area corresponding to the first conductive layer 101 on the Z-axis is the first detection area 103, and the detection area corresponding to the second conductive layer 102 on the Z-axis is the second detection area 104. Other areas of the plate to be drilled 100 on the Z-axis are non-detection areas 105.

[0060] This embodiment first obtains the theoretical position information A2 of the first conductive layer 101 on the Z-axis and the theoretical position information B2 of the second conductive layer 102, then obtains the theoretical thickness T of the plate 100 to be drilled, and determines a preset value H based on the theoretical thickness T. Since both the first conductive layer 101 and the second conductive layer 102 have a certain thickness, their corresponding theoretical position information corresponds to the edge of each conductive layer facing the Z-axis direction, thus standardizing the position information. The actual coordinate information of each conductive layer is subsequently detected by the drilling equipment, and its actual coordinate information may not be consistent with the above standard; instead, the actual detection results of the drilling equipment shall prevail.

[0061] The upper limit of the first detection area 103 is located at position A1 on the Z-axis, and A1 = A2 + H; the lower limit of the first detection area 103 is located at position A3 on the Z-axis, and A3 = A2 - H. The upper limit of the second detection area 104 is located at position B1 on the Z-axis, and B1 = B2 + H; the lower limit of the second detection area 104 is located at position B3 on the Z-axis, and B3 = B2 - H.

[0062] The upper limit of the non-detection area 105 is the lower limit A3 of the first detection area 103, and the lower limit is the upper limit B1 of the second detection area 104.

[0063] The above method determines the position information of the detection area and non-detection area on the Z-axis of the plate to be drilled. When preparing the target through hole, the plate to be drilled is drilled along the Z-axis direction in each area until it penetrates the plate to obtain the target through hole. Therefore, after determining the position information of the detection area and non-detection area on the Z-axis, the drilling equipment can accurately adjust its sensitivity based on the position information of the detection area and non-detection area on the Z-axis to perform detection, thereby improving the detection accuracy.

[0064] Step S23: Drill holes in the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and drill holes in the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole, and detect the actual position information of the target conductive layer during the drilling process, wherein the first sensitivity is greater than the second sensitivity.

[0065] After determining the location information of the first detection area, the second detection area, and the non-detection area, drilling is performed on the first detection area and the second detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and drilling is performed on the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole. The actual location information of the first conductive layer and the second conductive layer are detected during the drilling process, wherein the first sensitivity is greater than the second sensitivity.

[0066] Since the first sensitivity is greater than the second sensitivity, the drilling equipment is in a high-sensitivity state when drilling the first and second detection areas. This high sensitivity allows the drill tip to improve detection accuracy when contacting the first and second conductive layers, thereby increasing the accuracy of the detected actual positions of the first and second conductive layers. Conversely, the drilling equipment is in a low-sensitivity state when drilling non-detection areas. This reduces abnormal signals generated by the drill body contacting the conductive layers, thus minimizing the impact of mixed signals on detection accuracy and further improving the overall detection accuracy.

[0067] Step S24: Determine the actual thickness of the plate to be drilled based on the actual position information of the first conductive layer and the second conductive layer, and determine the depth control based on the actual thickness of the plate to be drilled and the first depth control ratio.

[0068] After obtaining the actual position information of the first conductive layer and the second conductive layer, since the first conductive layer and the second conductive layer are the surface conductive layers of the plate to be drilled, the actual thickness of the plate to be drilled can be obtained. The actual thickness of the plate to be drilled refers to the thickness of the entire plate to be drilled.

[0069] The depth of control is determined based on the actual thickness of the plate to be drilled and the first depth control ratio. Specifically, the actual thickness of the plate to be drilled can be multiplied by the first depth control ratio to obtain the depth of control required for back drilling of the target through hole. In other application scenarios, the depth of control can also be determined using other calculation methods based on the actual thickness of the plate to be drilled and the first depth control ratio, which are not limited here. The first depth control ratio is the theoretical depth control ratio between the first conductive layer and the second conductive layer.

[0070] The depth of control can be calculated using the above method, based on the actual thickness of the plate to be drilled and the set first depth control ratio, thereby ensuring the accuracy of the depth of control.

[0071] Step S25: Drill the target through hole based on the controlled depth to prepare the printed circuit board.

[0072] In a specific application scenario, the target via can be metallized before drilling to ensure the conductivity of the target via connecting the various conductive layers.

[0073] After obtaining the depth of control, the target through hole is drilled based on the depth of control, thereby back-drilling the target through hole to prepare the printed circuit board.

[0074] Through the above steps, the printing circuit board drilling method of this embodiment drills holes in the detection area of ​​the board to be drilled based on a first sensitivity of the drilling equipment, and drills holes in the non-detection area of ​​the board to be drilled based on a second sensitivity of the drilling equipment, thereby obtaining a target through hole. During the drilling process, the actual position information of the target conductive layer is detected. The first sensitivity is greater than the second sensitivity, which allows the drill tip of the drilling equipment to improve the detection accuracy of the drilling equipment when contacting the first and second conductive layers during the preparation of the target through hole, thus improving the accuracy of the detected actual position information of the first and second conductive layers. When drilling in the non-detection area, the drilling equipment is in a low-sensitivity state, which reduces abnormal signals generated by the contact between the drill body and each conductive layer, thereby reducing the impact of mixed signals on the detection accuracy and further improving the detection accuracy of the drilling equipment. Ultimately, this improves the accuracy and precision of the depth control, enhances the accuracy of back drilling of the target through hole, and achieves high-precision control of the back drilling stub. Furthermore, this embodiment also uses the method of adding or subtracting set values ​​from the theoretical position information of the first conductive layer to obtain the upper and lower limits of the first detection area; and adding or subtracting set values ​​from the theoretical position information of the second conductive layer to obtain the upper and lower limits of the second detection area to determine the preset range of the first detection area and the second detection area. This ensures to a certain extent that the first conductive layer and the second conductive layer are located in the corresponding first detection area and the second detection area, respectively. As a result, when the drilling equipment drills in the first detection area and the second detection area, the adjusted first sensitivity is fully utilized, ensuring the effectiveness and reliability of the dynamic adjustment state setting.

[0075] Please see Figure 4 , Figure 4 This is a flowchart illustrating another embodiment of the drilling method for printed circuit boards according to the present invention. The target conductive layer in this embodiment includes a first conductive layer and a reference conductive layer. The first conductive layer is the surface conductive layer of the board to be drilled, and the reference conductive layer is the inner conductive layer of the board to be drilled. When drilling the target through-hole, the drilling passes through the first conductive layer and the reference conductive layer until the controlled drilling depth is reached.

[0076] Step S31: Obtain the theoretical position information of the plate to be drilled, the first conductive layer of the plate to be drilled, and the reference conductive layer.

[0077] The theoretical position information of the plate to be drilled, its first conductive layer, and the reference conductive layer is obtained. In this embodiment, the theoretical position information may include coordinate information.

[0078] The method for obtaining the theoretical location information of the target conductive layer in this step is the same as that in the aforementioned embodiments, please refer to the previous text, and will not be repeated here.

[0079] Step S32: Determine the detection area based on the preset range of the theoretical position information of the first conductive layer and the reference conductive layer, and determine other areas besides the detection area as non-detection areas.

[0080] After obtaining the theoretical location information of the first conductive layer and the reference conductive layer, a detection area is determined based on the preset range where the theoretical location information of the first conductive layer and the reference conductive layer is located, and other areas other than the detection area are determined as non-detection areas. Since the target conductive layer is divided into a first conductive layer and a reference conductive layer, the detection area in this embodiment is also divided into a first detection area and a second detection area, corresponding to include the first conductive layer and the reference conductive layer.

[0081] The preset range can be set based on the theoretical thickness of the plate to be drilled or set to a fixed value, such as 2 cm or 3 cm, without specific limitations. Since there may be errors between the theoretical and actual position information, setting a preset range near the theoretical position information can, to a certain extent, ensure that the first conductive layer and the reference conductive layer are located within their respective detection areas, thereby improving the detection accuracy during drilling.

[0082] In one specific implementation, after obtaining the theoretical position information of the first conductive layer and the reference conductive layer, the theoretical thickness of the plate to be drilled can be obtained first, and a preset value of a preset range can be determined based on the theoretical thickness, wherein the preset value is 1 / 2 of the preset range; the theoretical position information of the first conductive layer is added to the preset value to obtain the upper limit of the first detection area, and the theoretical position information of the first conductive layer is subtracted from the preset value to determine the lower limit of the first detection area; and the theoretical position information of the reference conductive layer is added to the preset value to obtain the upper limit of the second detection area, and the theoretical position information of the reference conductive layer is subtracted from the preset value to determine the lower limit of the second detection area.

[0083] Please see Figure 5 , Figure 5 yes Figure 4 A schematic diagram illustrating another implementation method for determining the detection area in the examples.

[0084] In this embodiment, the detection area corresponding to the first conductive layer 201 of the plate to be drilled 200 on the Z-axis is the first detection area 203, and the detection area corresponding to the reference conductive layer 202 on the Z-axis is the second detection area 204. The area between the first detection area 203 and the second detection area 204 is the non-detection area 205. In this embodiment, the drilling equipment only needs to probe from the first detection area 203 to the second detection area 204, without needing to probe throughout the entire plate.

[0085] In a specific application scenario, this embodiment first obtains the theoretical position information C2 of the first conductive layer 201 on the Z-axis and the theoretical position information D2 of the reference conductive layer 202, then obtains the theoretical thickness T of the plate 200 to be drilled, and determines a preset range setting value H based on the theoretical thickness T. Since both the first conductive layer 201 and the reference conductive layer 202 have a certain thickness, their corresponding theoretical position information corresponds to the edge of each conductive layer facing the Z-axis direction, thus standardizing the position information. The actual coordinate information of each conductive layer is subsequently detected by the drilling equipment, and its actual coordinate information may not be consistent with the above standard, but rather based on the actual detection results of the drilling equipment. Therefore, the position information of the upper limit of the first detection area 203 on the Z-axis is C1, and C1 = C2 + H; the position information of the lower limit of the first detection area 203 on the Z-axis is C3, and C3 = C2 - H. The upper limit of the second detection area 204 is located at position D1 on the Z-axis, and D1 = D2 + H; the lower limit of the second detection area 204 is located at position D3 on the Z-axis, and D3 = D2 - H.

[0086] In a specific application scenario, D2 can be equal to C2 minus the distance between the first detection area 203 and the second detection area 204.

[0087] The upper limit of the non-detection area 205 is the lower limit C3 of the first detection area 203, and the lower limit is the upper limit D1 of the second detection area 204.

[0088] The above method determines the position information of the detection area and non-detection area on the Z-axis of the plate to be drilled. When preparing the target through hole, the plate to be drilled is drilled along the Z-axis direction in each area until it penetrates the plate to obtain the target through hole. Therefore, after determining the position information of the detection area and non-detection area on the Z-axis, the drilling equipment can accurately adjust its sensitivity based on the position information of the detection area and non-detection area on the Z-axis to perform detection, thereby improving the detection accuracy.

[0089] Step S33: Drill holes in the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and drill holes in the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole, and detect the actual position information of the target conductive layer during the drilling process, wherein the first sensitivity is greater than the second sensitivity.

[0090] After determining the location information of the first detection area, the second detection area, and the non-detection area, drilling is performed on the first and second detection areas of the board to be drilled based on the first sensitivity of the drilling equipment, and drilling is performed on the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole. The actual location information of the first conductive layer and the reference conductive layer are detected during the drilling process, wherein the first sensitivity is greater than the second sensitivity.

[0091] Since the first sensitivity is greater than the second sensitivity, the drilling equipment is in a high-sensitivity state when drilling the first and second detection areas. This high sensitivity allows the drill tip to improve detection accuracy when contacting the first conductive layer and the reference conductive layer, thereby increasing the accuracy of the detected actual position information of the first and reference conductive layers. Conversely, the drilling equipment is in a low-sensitivity state when drilling non-detection areas. This reduces abnormal signals generated by the drill body contacting the conductive layers, thus minimizing the impact of mixed signals on detection accuracy and further improving the overall detection accuracy.

[0092] Step S34: Determine the distance between the first conductive layer and the reference conductive layer based on the actual position information of the first conductive layer and the actual position information of the reference conductive layer, and determine the control depth by summing the distance between the first conductive layer and the reference conductive layer and the control depth value of the reference conductive layer in the direction away from the first conductive layer.

[0093] After detecting the actual position information of the first conductive layer and the actual position information of the reference conductive layer by the drilling equipment, the distance between the first conductive layer and the reference conductive layer is determined based on the actual position information of the first conductive layer and the reference conductive layer. The sum of the distance between the first conductive layer and the reference conductive layer and the control depth value in the direction away from the first conductive layer is determined as the control depth.

[0094] In the process of drilling the target through-hole, the drilling passes through the first conductive layer and the reference conductive layer until the control depth is reached. Therefore, the area between the first conductive layer and the reference conductive layer is the area that needs to be traversed when drilling the target through-hole. After detecting the actual distance between the first conductive layer and the reference conductive layer, the control depth is composed of the accurate distance between the first conductive layer and the reference conductive layer and the theoretical control depth value of the direction away from the first conductive layer. This can reduce the error of the control depth to a certain extent and improve the drilling accuracy.

[0095] In other embodiments, after obtaining the actual position information of the first conductive layer and the actual position information of the reference conductive layer, and obtaining the actual distance between the first conductive layer and the reference conductive layer, the distance between the reference conductive layer and the second conductive layer on the board to be drilled, located on the opposite side of the first conductive layer, can be obtained by subtracting the distance between the first conductive layer and the reference conductive layer from the thickness of the board to be drilled. Then, the distance between the reference conductive layer and the second conductive layer is multiplied by the second control depth ratio to obtain the control depth of the entire board between the reference conductive layer and the second conductive layer. Finally, this depth is added to the actual distance between the first conductive layer and the reference conductive layer to obtain the control depth. The second control depth ratio is the theoretical control depth ratio between the reference conductive layer and the second conductive layer.

[0096] Among them, the calculation method of the aforementioned controlled depth is similar to... Figure 2 The method for calculating the depth control in the embodiment is similar, but by subtracting the actual distance between the first conductive layer and the reference conductive layer from the entire board thickness, and then calculating the depth control based on the remaining board thickness and the second depth control ratio, the accuracy of the depth control can be further improved.

[0097] Step S35: Drill the target through hole based on the controlled depth to prepare the printed circuit board.

[0098] After obtaining the depth of control, the target through hole is drilled based on the depth of control, thereby back-drilling the target through hole to prepare the printed circuit board.

[0099] Through the above steps, the printing circuit board drilling method of this embodiment drills holes in the detection area of ​​the board to be drilled based on a first sensitivity of the drilling equipment, and drills holes in the non-detection area of ​​the board to be drilled based on a second sensitivity of the drilling equipment, thereby obtaining a target through-hole. During the drilling process, the actual position information of the target conductive layer is detected. The first sensitivity is greater than the second sensitivity, which allows the drill tip of the drilling equipment to improve the detection accuracy of the drilling equipment when contacting the first conductive layer and the reference conductive layer during the preparation of the target through-hole, thus improving the accuracy of the detected actual position information of the first conductive layer and the reference conductive layer. When drilling in the non-detection area, the drilling equipment is in a low-sensitivity state, which reduces abnormal signals generated by the contact between the drill body and each conductive layer, thereby reducing the impact of mixed signals on the detection accuracy and further improving the detection accuracy of the drilling equipment. Ultimately, this improves the accuracy and precision of the depth control, enhances the accuracy of back-drilling the target through-hole, and achieves high-precision control of the back-drilling stub. Furthermore, this embodiment also uses the method of adding or subtracting set values ​​from the theoretical position information of the first conductive layer to obtain the upper and lower limits of the first detection area; and adding or subtracting set values ​​from the theoretical position information of the reference conductive layer to obtain the upper and lower limits of the second detection area to determine the preset range of the first detection area and the second detection area. This ensures to a certain extent that the first conductive layer and the reference conductive layer are located in the corresponding first detection area and the second detection area, respectively. As a result, when the drilling equipment drills in the first detection area and the second detection area, the adjusted first sensitivity is fully utilized, ensuring the effectiveness and reliability of the dynamic adjustment state setting.

[0100] Please see Figure 6 , Figure 6 This is a schematic diagram of a printed circuit board according to an embodiment of the present invention. The structure of the printed circuit board in this embodiment is only illustrated for the back-drilling structure and does not limit other structures of the printed circuit board.

[0101] The conductive layer in the printed circuit board 300 of this embodiment includes at least a first conductive layer 301, a reference conductive layer 302, a target conductive layer 303, and a second conductive layer 304, wherein the first conductive layer 301, the reference conductive layer 302, the target conductive layer 303, and the second conductive layer 304 are sequentially stacked and bonded to the insulating layer 305.

[0102] The printed circuit board 300 also includes a target through-hole 306, and a back-drilled hole 307 is provided on one side of the target through-hole 306. The bottom of the back-drilled hole 307 needs to maintain a certain distance from the target conductive layer 303, that is, the controlled depth of the back-drilled hole 307 needs to ensure that the above-mentioned distance is maintained.

[0103] In this embodiment, the printed circuit board 300 is prepared by drilling the printed circuit board of any of the above embodiments.

[0104] With the above structure, the back-drilled holes of the printed circuit board in this embodiment have higher precision, reducing the possibility of damaging the target conductive layer and ensuring that the distance between the back-drilled holes and the target conductive layer meets the standard, thereby improving the stability and reliability of the printed circuit board.

[0105] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A drilling method for a printed circuit board, characterized in that, The drilling method for the printed circuit board includes: Obtain the theoretical location information of the plate to be drilled and the target conductive layer of the plate to be drilled; The detection area and non-detection area of ​​the plate to be drilled are determined based on the theoretical location information of the target conductive layer; wherein, the detection area is the area within a preset range where the target conductive layer is located, determined based on the theoretical location information of the target conductive layer, and the non-detection area is the area other than the detection area; Drilling is performed on the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and drilling is performed on the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole, and the actual position information of the target conductive layer is detected during the drilling process, wherein the first sensitivity is greater than the second sensitivity; The depth of the target via is determined based on the actual position information of the target conductive layer; The target through-hole is drilled based on the controlled depth to prepare the printed circuit board.

2. The drilling method for a printed circuit board according to claim 1, characterized in that, The steps of drilling a target through hole based on a first sensitivity of the drilling equipment to drill a detection area of ​​the plate to be drilled, and drilling a non-detection area of ​​the plate to be drilled based on a second sensitivity of the drilling equipment, include: The voltage of the detection circuit of the drilling equipment is adjusted to a first voltage to set the sensitivity of the drilling equipment to the first sensitivity, and the voltage of the detection circuit of the drilling equipment is adjusted to a second voltage to set the sensitivity of the drilling equipment to the second sensitivity. Wherein, the first voltage is greater than the second voltage.

3. The drilling method for a printed circuit board according to claim 1, characterized in that, The target conductive layer includes a first conductive layer and a second conductive layer, wherein the first conductive layer and the second conductive layer are respectively the surface conductive layers of the plate to be drilled; The step of determining the detection area and non-detection area of ​​the plate to be drilled based on the theoretical position information of the target conductive layer includes: The detection area is determined based on a preset range of the theoretical location information of the first conductive layer and the second conductive layer. Areas other than the detection area are defined as non-detection areas.

4. The drilling method for a printed circuit board according to claim 3, characterized in that, The detection area includes a first detection area and a second detection area; The step of determining the detection area based on the preset range of the theoretical location information of the first conductive layer and the second conductive layer includes: The theoretical thickness of the plate to be drilled is obtained, and a set value of the preset range is determined based on the theoretical thickness, wherein the set value is 1 / 2 of the preset range; Adding the set value to the theoretical position information of the first conductive layer yields the upper limit of the first detection area; subtracting the set value from the theoretical position information of the first conductive layer determines the lower limit of the first detection area. The upper limit of the second detection area is obtained by adding the theoretical position information of the second conductive layer to the set value, and the lower limit of the second detection area is determined by subtracting the set value from the theoretical position information of the second conductive layer.

5. The drilling method for a printed circuit board according to claim 3, characterized in that, The step of determining the drilling depth of the plate to be drilled based on the actual position information of the target conductive layer includes: The actual thickness of the plate to be drilled is determined based on the actual position information of the first conductive layer and the second conductive layer. The depth of control is determined based on the actual thickness of the plate to be drilled and the first depth control ratio.

6. The drilling method for a printed circuit board according to claim 1, characterized in that, The target conductive layer includes a first conductive layer and a reference conductive layer. The first conductive layer is the surface conductive layer of the plate to be drilled, and the reference conductive layer is the inner conductive layer of the plate to be drilled. The step of determining the detection area and non-detection area of ​​the plate to be drilled based on the theoretical position information of the target conductive layer includes: The detection area is determined based on a preset range of the theoretical location information of the first conductive layer and the reference conductive layer. Areas other than the detection area are defined as non-detection areas.

7. The drilling method for a printed circuit board according to claim 6, characterized in that, The detection area includes a first detection area and a second detection area; The step of determining the detection area based on the preset range of the theoretical location information of the first conductive layer and the reference conductive layer includes: The theoretical thickness of the plate to be drilled is obtained, and a set value of the preset range is determined based on the theoretical thickness, wherein the set value is 1 / 2 of the preset range; Adding the set value to the theoretical position information of the first conductive layer yields the upper limit of the first detection area; subtracting the set value from the theoretical position information of the first conductive layer determines the lower limit of the first detection area. The upper limit of the second detection area is obtained by adding the set value to the theoretical position information of the reference conductive layer, and the lower limit of the second detection area is determined by subtracting the set value from the theoretical position information of the reference conductive layer.

8. The drilling method for a printed circuit board according to claim 6, characterized in that, The step of determining the drilling depth of the plate to be drilled based on the actual position information of the target conductive layer includes: The distance between the first conductive layer and the reference conductive layer is determined based on the actual position information of the first conductive layer and the actual position information of the reference conductive layer; The control depth is determined by the sum of the distance between the first conductive layer and the reference conductive layer and the control depth value of the reference conductive layer in the direction away from the first conductive layer.

9. The drilling method for a printed circuit board according to claim 1, characterized in that, The steps of drilling the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and drilling the non-detection area of ​​the board to be drilled based on the second sensitivity of the drilling equipment to obtain the target through hole, and detecting the actual position information of the target conductive layer during the drilling process, further include: In response to drilling the detection area of ​​the board to be drilled based on the first sensitivity of the drilling equipment, and after detecting the target conductive layer in the detection area, the drilling equipment is adjusted to the second sensitivity to drill until the next detection area is reached.

10. A printed circuit board, characterized in that, The printed circuit board is prepared by the drilling method of the printed circuit board according to any one of claims 1-9.

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