PCB back drilling method, controller and apparatus

Abstract

The application discloses a PCB back drilling method, a controller and equipment, and comprises the following steps: obtaining a PCB back drilling request corresponding to a to-be-processed PCB, wherein the PCB back drilling request comprises to-be-processed via hole parameters, to-be-processed PCB parameters and prepreg parameters corresponding to a target prepreg; determining a target thickness corresponding to the target prepreg based on the to-be-processed via hole parameters, the to-be-processed PCB parameters and the prepreg parameters; and performing back drilling on a to-be-processed via hole corresponding to the to-be-processed via hole parameters on the to-be-processed PCB based on the target thickness and the to-be-processed PCB parameters, so as to obtain a target back drilling via hole. The technical scheme can avoid the influence of glue flow on the back drilling precision of the target prepreg, and realize high-precision control of back drilling.

Description

Technical Field

[0001] This invention relates to the field of PCB technology, and more particularly to a PCB back drilling method, controller, and equipment. Background Technology

[0002] With the increasing diversification and integration of electronic products, the number of layers and the density of printed circuit boards (PCBs) are also increasing, leading to poorer uniformity in board thickness and dielectric thickness, as well as irregular distribution of circuit patterns on PCBs. This severely impacts PCB back-drilling and impedance control. Currently, theoretical board thickness / dielectric thickness calculations only differentiate between different PCB layers, failing to calculate dielectric thickness at different locations on the PCB surface. Therefore, it's difficult to achieve different drilling depths for different back-drill holes depending on dielectric thickness, resulting in difficulty controlling back-drilling accuracy. To address this issue, the industry has adopted methods such as partitioned or hole-by-hole thickness compensation, but these methods have significant errors. Therefore, improving back-drilling accuracy has become a pressing technical problem. Summary of the Invention

[0003] This invention provides a PCB back drilling method, controller, and device to solve the problem of poor back drilling accuracy in existing PCB back drilling methods.

[0004] A PCB back-drilling method, comprising:

[0005] Obtain the PCB back drilling request corresponding to the PCB to be processed. The PCB back drilling request includes the through hole parameters to be processed, the PCB parameters to be processed, and the prepreg parameters corresponding to the target prepreg.

[0006] Based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg, the target thickness corresponding to the target prepreg is determined;

[0007] Based on the target thickness and the parameters of the PCB to be processed, back drilling is performed on the through hole corresponding to the parameters of the through hole to be processed on the PCB to be processed, to obtain the target back drilled through hole.

[0008] Further, determining the target thickness of the target prepreg based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg includes:

[0009] Based on the parameters of the through hole to be processed and the parameters of the prepreg, the local flow region of the prepreg is determined;

[0010] Based on the prepreg parameters and the PCB parameters to be processed, the target thickness of the target prepreg within the local prepreg flow area is determined.

[0011] Furthermore, the parameters of the through hole to be processed include the coordinates of the through hole to be processed; the parameters of the prepreg include the flow coefficient of the prepreg.

[0012] The step of determining the local flow region of the prepreg based on the parameters of the through-hole to be processed and the parameters of the prepreg includes:

[0013] The target flow area is determined based on the flow coefficient of the prepreg.

[0014] Based on the coordinates of the through-hole to be processed and the target flow area, the local semi-cured sheet flow region centered on the coordinates of the through-hole to be processed is determined.

[0015] Further, based on the prepreg parameters and the PCB parameters to be processed, the target thickness of the target prepreg within the local prepreg flow area is determined:

[0016] Based on the parameters of the PCB to be processed, the target residual copper ratio of each PCB layer in the local prepreg flow area is determined.

[0017] Based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio, the target thickness of the target prepreg within the local prepreg flow area is determined.

[0018] Furthermore, the prepreg parameters include the initial prepreg thickness; the PCB parameters to be processed include the initial PCB thickness and the thickness of each metal layer;

[0019] The determination of the target thickness of the target prepreg within the local prepreg flow area based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio includes:

[0020] Detect the actual PCB thickness corresponding to the PCB to be processed;

[0021] Based on the actual PCB thickness and the initial PCB thickness, the first calculation parameter is determined;

[0022] Based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg, the second calculation parameter is determined.

[0023] Based on the initial prepreg thickness, the first calculation parameter, and the second calculation parameter, the target thickness corresponding to the target prepreg in the PCB to be processed is determined.

[0024] Further, determining the first calculation parameter based on the actual PCB thickness and the initial PCB thickness includes: determining a thickness difference based on the actual PCB thickness and the initial PCB thickness, and determining the quotient between the thickness difference and the initial PCB thickness as the first calculation parameter.

[0025] Further, the determination of the second calculation parameter based on the metal layer thickness and target residual copper ratio corresponding to each metal layer in the target prepreg includes:

[0026] The actual metal thickness of each metal layer is determined based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg.

[0027] The sum of the actual metal thicknesses of two adjacent metal layers is determined as the first target parameter, and the sum of the actual metal thicknesses of all metal layers is determined as the second target parameter. The quotient of the first target parameter and the second target parameter is determined as the second calculation parameter.

[0028] Further, the step of back-drilling on the through-hole corresponding to the through-hole parameters on the PCB to be processed, based on the target thickness and the parameters of the PCB to be processed, to obtain the target back-drilled through-hole, includes:

[0029] Determine the back drilling depth based on the target thickness and the parameters of the PCB to be processed;

[0030] Based on the back-drilling depth, the drilling equipment is controlled to perform back-drilling on the through-hole of the PCB to be processed, so as to obtain the target back-drilled through-hole.

[0031] A back-drilling controller, a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the PCB back-drilling method described above.

[0032] An automatic back-drilling device includes the aforementioned back-drilling controller.

[0033] The aforementioned PCB back-drilling method, controller, and equipment acquire a PCB back-drilling request corresponding to the PCB to be processed. The PCB back-drilling request includes parameters of the through-hole to be processed, parameters of the PCB to be processed, and parameters of the prepreg corresponding to the target prepreg. Based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg, the target thickness corresponding to the target prepreg is determined. Based on the target thickness and the parameters of the PCB to be processed, back-drilling is performed on the through-hole to be processed corresponding to the parameters of the through-hole to be processed on the PCB to be processed, thereby obtaining the target back-drilled through-hole. This avoids the impact of resin flow on the back-drilling accuracy of the target prepreg and achieves high-precision control of back-drilling. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a flowchart of a PCB back-drilling method according to an embodiment of the present invention;

[0036] Figure 2 This is another flowchart of a PCB back-drilling method in one embodiment of the present invention;

[0037] Figure 3 This is another flowchart of a PCB back-drilling method in one embodiment of the present invention;

[0038] Figure 4 This is another flowchart of a PCB back-drilling method in one embodiment of the present invention;

[0039] Figure 5 This is another flowchart of a PCB back-drilling method in one embodiment of the present invention;

[0040] Figure 6 This is another flowchart of a PCB back-drilling method in one embodiment of the present invention;

[0041] Figure 7 This is another flowchart of a PCB back-drilling method in one embodiment of the present invention. Detailed Implementation

[0042] 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, not all, of the embodiments of the present invention. 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.

[0043] It should be understood that the invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0044] To fully understand this invention, detailed structures and steps will be presented in the following description to illustrate the technical solution proposed by this invention. Preferred embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0045] This invention provides a PCB back drilling method. Specifically, this PCB back drilling method is applied in an automatic back drilling device, which includes a controller and a drilling mechanism. The automatic back drilling device has a processing position for placing the PCB to be processed. The controller is used to execute the above-described PCB back drilling method, controlling the drilling mechanism to perform back drilling on the PCB to be processed at the processing position, thereby improving the back drilling accuracy.

[0046] In one embodiment, such as Figure 1 As shown, a PCB back drilling method is provided, which is illustrated using the controller in the automatic drilling equipment as an example. The method includes the following steps:

[0047] S101: Obtain the PCB back drilling request corresponding to the PCB to be processed. The PCB back drilling request includes the parameters of the through hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg corresponding to the target prepreg.

[0048] S102: Determine the target thickness of the target prepreg based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg.

[0049] S103: Based on the target thickness and the parameters of the PCB to be processed, back drilling is performed on the through hole corresponding to the parameters of the through hole to be processed on the PCB to be processed, so as to obtain the target back drilled through hole.

[0050] The PCB to be processed refers to a PCB board that requires PCB back drilling. The PCB to be processed includes at least three pre-laminated PCB layers. A target prepreg is provided between two adjacent PCB layers. At least one through-hole is pre-machined on the PCB to be processed. The through-hole refers to a PCB hole on the PCB to be processed. The parameters of the through-hole refer to the parameters corresponding to the through-hole. For example, the through-hole parameters include the coordinates of the through-hole, its diameter, and the number of PCB layers to be connected. The PCB parameters refer to the parameters corresponding to the PCB to be processed. For example, the PCB parameters include the number of PCB layers, the thickness of the metal layers in the PCB, and the residual copper ratio of the PCB. The target prepreg is a prepreg disposed between the metal layers of two adjacent PCB layers. For example, the prepreg parameters include the initial prepreg thickness and the prepreg flow coefficient. The initial prepreg thickness refers to the thickness of the target prepreg before lamination.

[0051] As an example, in step S101, the controller obtains the PCB back drilling request corresponding to the PCB to be processed, ensuring that the PCB back drilling request includes the parameters of the through hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg corresponding to the target prepreg. This enables the controller to perform back drilling on the through hole to be processed on the PCB to be processed based on the parameters of the through hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg corresponding to the target prepreg.

[0052] The target thickness refers to the thickness of the target prepreg after lamination.

[0053] As an example, in step S102, the target thickness of the target prepreg is determined based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg. In this example, the controller determines the target thickness of the target prepreg based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg, using a preset prepreg thickness calculation strategy. This preset prepreg thickness calculation strategy refers to a pre-set calculation strategy used to calculate the target thickness of the target prepreg. It should be noted that during the process of pre-laminating at least three layers of PCB to obtain the PCB to be processed, the thickness of the PCB and the uniformity of dielectric thickness among the at least three layers of PCB can easily be affected, resulting in poor back-drilling accuracy of the through-holes to be processed in the subsequent PCB. In related technologies, the back-drilling depth is calculated by proportionally altering the thickness of the PCB to be processed and the position of the PCBs to be connected within it. However, this method fails to consider that the thickness of the prepreg changes due to adhesive flow during lamination, while the PCB thickness remains relatively constant. Furthermore, it doesn't account for the impact of residual copper on the prepreg's thickness after adhesive flow, leading to inaccurate back-drilling depth calculations. Therefore, this example determines the target thickness of the prepreg based on the parameters of the through-holes, the PCB to be processed, and the prepreg parameters. This allows for the calculation of the actual thickness of the prepreg after lamination, i.e., the target thickness. This ensures accurate calculation of the target thickness after adhesive flow, resulting in a more precise back-drilling depth in subsequent steps and improved back-drilling accuracy.

[0054] Among them, the target back-drilled through hole refers to the PCB hole obtained after back-drilling the through hole to be processed.

[0055] As an example, in step S103, based on the target thickness and the parameters of the PCB to be processed, back drilling is performed on the through-holes corresponding to the parameters of the through-holes to be processed on the PCB to be processed, resulting in the target back-drilled through-hole. In this embodiment, the parameters of the PCB to be processed also include the PCB board thickness, which includes the core board thickness and the metal layer thickness on the core board. Based on the target thickness, and the number of layers and the PCB board thickness in the parameters of the PCB to be processed, the back drilling depth can be determined. Based on the back drilling depth, back drilling is performed on the through-holes corresponding to the parameters of the through-holes to be processed on the PCB to be processed, resulting in the target back-drilled through-hole. This avoids the impact of adhesive flow on the back drilling accuracy of the target prepreg, achieving high-precision control of the back drilling.

[0056] In this embodiment, a PCB back-drilling request corresponding to the PCB to be processed is obtained. The PCB back-drilling request includes the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg corresponding to the target prepreg. Based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg, the target thickness corresponding to the target prepreg is determined. Based on the target thickness and the parameters of the PCB to be processed, back-drilling is performed on the through-hole to be processed corresponding to the parameters of the through-hole to be processed on the PCB to be processed, thereby obtaining the target back-drilled through-hole. This avoids the impact of resin flow on the back-drilling accuracy of the target prepreg and achieves high-precision control of back-drilling.

[0057] In one embodiment, such as Figure 2 As shown, in step S102, based on the parameters of the through-hole to be processed, the parameters of the PCB to be processed, and the parameters of the prepreg, the target thickness corresponding to the target prepreg is determined, including:

[0058] S201: Determine the local flow area of ​​the prepreg based on the parameters of the through hole to be processed and the parameters of the prepreg.

[0059] S202: Based on the prepreg parameters and the PCB parameters to be processed, determine the target thickness of the target prepreg within the local prepreg flow area.

[0060] The localized semi-cured sheet flow area refers to the region on the PCB to be processed used to calculate the target thickness.

[0061] As an example, in step S201, a local prepreg flow region is determined based on the parameters of the through-hole to be processed and the prepreg parameters. In this example, the controller determines the local prepreg flow region based on the parameters of the through-hole to be processed and the prepreg parameters using a preset local flow region calculation logic. The preset local flow region calculation logic refers to a custom-defined logic used to determine the local prepreg flow region based on the parameters of the through-hole to be processed and the prepreg parameters. In this example, determining the local prepreg flow region based on the parameters of the through-hole to be processed and the prepreg parameters facilitates the calculation of the target thickness of the target prepreg within the local area of ​​the through-hole to be processed, thereby further improving back-drilling accuracy.

[0062] As an example, in step S202, based on the prepreg parameters and the PCB parameters to be processed, the target thickness of the target prepreg within the local prepreg flow area is determined. In this example, after the controller determines the local prepreg flow area, it can determine the target thickness of the target prepreg within the local prepreg flow area based on the prepreg parameters and the PCB parameters to be processed. This facilitates the calculation of the target thickness of the target prepreg within the local area of ​​the through-hole to be processed, thereby more accurately determining the thickness of the target prepreg after adhesive flow within the local area of ​​the through-hole to be processed, and thus more accurately determining the back-drilling depth, thereby further improving back-drilling accuracy.

[0063] In this embodiment, the controller determines the local prepreg flow area based on the parameters of the through-hole to be processed and the prepreg parameters. Based on the prepreg parameters and the PCB parameters to be processed, it determines the target thickness of the target prepreg within the local prepreg flow area. This facilitates the calculation of the target thickness of the target prepreg within the local area of ​​the through-hole to be processed, thereby more accurately determining the thickness of the target prepreg after adhesive flow within the local area of ​​the through-hole to be processed, and thus more accurately determining the back-drilling depth, thereby further improving the back-drilling accuracy.

[0064] In one embodiment, such as Figure 3 As shown, in step S201, the parameters of the through-hole to be processed include the coordinates of the through-hole; the parameters of the prepreg include the flow coefficient of the prepreg; based on the parameters of the through-hole to be processed and the parameters of the prepreg, the local flow region of the prepreg is determined, including:

[0065] S301: Determine the target flow area based on the flow coefficient of the prepreg.

[0066] S302: Based on the coordinates of the through-hole to be processed and the target flow area, determine the local semi-cured sheet flow area centered on the coordinates of the through-hole to be processed.

[0067] As an example, in step S301, the target flow area is the area used to determine the size of the local prepreg flow region. Understandably, the prepreg flow coefficient refers to the percentage of flowable resin in the target prepreg relative to the total resin volume. The prepreg flow coefficient is generally between 25% and 40%, and its content decreases as the glass cloth thickness increases. In this example, a larger prepreg flow coefficient results in a larger target flow area, and a smaller prepreg flow coefficient results in a smaller target flow area. It should be noted that the ratio of the prepreg flow coefficient to the target flow area can be determined based on practical experience, and no restrictions are imposed here.

[0068] As an example, in step S302, a local semi-cured sheet flow region centered on the coordinates of the through-hole to be processed is determined based on the coordinates of the through-hole to be processed and the target flow area. In this embodiment, the local semi-cured sheet flow region can be determined centered on the coordinates of the through-hole to be processed based on the coordinates of the through-hole to be processed and the target flow area. Preferably, the local semi-cured sheet flow region is circular.

[0069] In this embodiment, the target flow area is determined based on the flow coefficient of the prepreg. Based on the coordinates of the through hole to be processed and the target flow area, the local flow region of the prepreg centered on the coordinates of the through hole to be processed is determined. This facilitates the calculation of the target thickness of the prepreg within the local area of ​​the through hole to be processed, thereby more accurately determining the thickness of the prepreg after resin flow within the local area of ​​the through hole to be processed, and thus more accurately determining the back drilling depth, thereby further improving the back drilling accuracy.

[0070] In one embodiment, such as Figure 4 As shown, in step S202, based on the prepreg parameters and the PCB parameters to be processed, the target thickness of the target prepreg within the local prepreg flow area is determined:

[0071] S401: Based on the parameters of the PCB to be processed, determine the target residual copper rate of each layer of PCB board in the local semi-cured sheet flow area.

[0072] S402: Based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio, determine the target thickness of the target prepreg within the local prepreg flow area.

[0073] The target residual copper rate refers to the residual copper rate of each PCB layer in the local prepreg flow area of ​​the PCB to be processed.

[0074] As an example, in step S401, the parameters of the PCB to be processed include the PCB board area and the total residual copper ratio of each PCB layer. The total residual copper ratio can be detected and measured in advance through chemical analysis or other means, or it can employ techniques known to those skilled in the art, which will not be elaborated here. Specifically, the target residual copper ratio = total residual copper ratio x (area of ​​the local prepreg flow region / PCB board area). It can be understood that the target residual copper ratio for each PCB layer can be calculated based on the above target residual copper ratio.

[0075] As an example, in step S402, the target thickness of the target prepreg within the local prepreg flow area is determined based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio. In this embodiment, the target thickness of the target prepreg within the local prepreg flow area is determined based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio. This takes into account the influence of the target residual copper ratio on the thickness of the target prepreg after resin flow within the local area of ​​the through-hole to be processed, thereby more accurately determining the back-drilling depth and further improving back-drilling accuracy.

[0076] In this embodiment, based on the parameters of the PCB to be processed, the target residual copper ratio of each PCB layer in the local prepreg flow area is determined. Based on the prepreg parameters, the parameters of the PCB to be processed, and the target residual copper ratio, the target thickness of the target prepreg in the local prepreg flow area is determined. This takes into account the influence of the target residual copper ratio on the thickness of the target prepreg after the adhesive flows in the local area of ​​the through hole to be processed, thereby more accurately determining the back-drilling depth and further improving the back-drilling accuracy.

[0077] In one embodiment, such as Figure 5 As shown, in step S402, the prepreg parameters include the initial prepreg thickness; the PCB parameters to be processed include the initial PCB thickness and the thickness of each metal layer; based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio, the target thickness corresponding to the target prepreg within the local prepreg flow area is determined, including:

[0078] S501: Detect the actual PCB thickness corresponding to the PCB to be processed.

[0079] S502: Determine the first calculation parameter based on the actual PCB thickness and the initial PCB thickness.

[0080] S503: Determine the second calculation parameter based on the metal layer thickness and target residual copper ratio corresponding to each metal layer in the target prepreg.

[0081] S504: Based on the initial prepreg thickness, the first calculation parameter, and the second calculation parameter, determine the target thickness corresponding to the target prepreg in the PCB to be processed.

[0082] The actual PCB thickness refers to the overall thickness of the PCB to be processed after lamination. The initial prepreg thickness refers to the overall thickness of the PCB to be processed before lamination.

[0083] As an example, in step S501, the controller detects the actual PCB thickness corresponding to the PCB to be processed by controlling the detection device on the automatic back drilling equipment. Preferably, the actual PCB thickness corresponding to the local semi-cured sheet flow area on the PCB to be processed is detected.

[0084] As an example, in step S502, the first calculation parameter refers to a parameter determined based on the actual PCB thickness and the initial PCB thickness, used to calculate the target thickness corresponding to the target prepreg in the PCB to be processed. In this example, the controller calculates the first calculation parameter using a first calculation strategy based on the actual PCB thickness and the initial PCB thickness. This first calculation strategy refers to a custom-set strategy used to calculate the first calculation parameter.

[0085] As an example, in step S503, the second calculation parameter refers to a parameter determined based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg, used to calculate the target thickness of the target prepreg in the PCB to be processed. In this example, the controller calculates the second calculation parameter using a second calculation strategy based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg. This second calculation strategy refers to a custom-set strategy used to calculate the second calculation parameter.

[0086] As an example, in step S504, the controller determines the target thickness of the target prepreg in the PCB to be processed by using a preset prepreg thickness calculation strategy based on the initial prepreg thickness, the first calculation parameter, and the second calculation parameter.

[0087] In this embodiment, by detecting the actual PCB thickness corresponding to the PCB to be processed, a first calculation parameter is determined based on the actual PCB thickness and the initial PCB thickness. A second calculation parameter is determined based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg. Based on the initial prepreg thickness, the first calculation parameter, and the second calculation parameter, the target thickness corresponding to the target prepreg in the PCB to be processed can be determined. This takes into account the influence of the target residual copper ratio on the thickness of the target prepreg after adhesive flow in the local area of ​​the through-hole to be processed, thereby more accurately determining the back-drilling depth and further improving the back-drilling accuracy.

[0088] In one embodiment, determining a first calculation parameter based on the actual PCB thickness and the initial PCB thickness includes: determining a thickness difference based on the actual PCB thickness and the initial PCB thickness, and determining the quotient between the thickness difference and the initial PCB thickness as the first calculation parameter.

[0089] As an example, the first calculation parameter is: Where t is the actual PCB thickness and T is the initial PCB thickness. In this embodiment, after obtaining the actual PCB thickness and the initial PCB thickness, the quotient between the thickness difference and the initial PCB thickness can be determined as the first calculation parameter to facilitate the subsequent calculation of the target thickness.

[0090] In one embodiment, such as Figure 6As shown, in step S503, based on the metal layer thickness and target residual copper ratio corresponding to each metal layer in the target prepreg, the second calculation parameter is determined, including:

[0091] S601: Determine the actual metal thickness of each metal layer based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg.

[0092] S602: The sum of the actual metal thicknesses corresponding to two adjacent metal layers is determined as the first target parameter, and the sum of the actual metal thicknesses corresponding to all metal layers is determined as the second target parameter. The quotient of the first target parameter and the second target parameter is determined as the second calculation parameter.

[0093] As an example, in step S601, the actual metal thickness is: Li*(1-hi), where Li is the metal layer thickness corresponding to each metal layer, and hi is the target residual copper ratio of each PCB board. i≥1.

[0094] As an example, in step S602, assuming the thickness of the target prepreg between the first metal layer and the second metal layer is calculated, the second calculation parameter is determined as follows: Where n is the number of layers of the PCB to be processed, n>i≥3.

[0095] For example, based on the initial prepreg thickness, a first calculation parameter, and a second calculation parameter, the target thickness corresponding to the target prepreg between the first metal layer and the second metal layer is determined as follows: Where p1 is the target thickness and P1 is the initial prepreg thickness.

[0096] In this embodiment, the target thickness of the target prepreg in the PCB to be processed can be determined by the above calculation strategy. The influence of the target residual copper rate on the thickness of the target prepreg after the adhesive is applied in the local area of ​​the through hole to be processed can be taken into account, thereby making the back drilling depth more accurate and improving the back drilling accuracy.

[0097] In one embodiment, such as Figure 7 As shown, in step S103, based on the target thickness and the parameters of the PCB to be processed, back drilling is performed on the through-holes corresponding to the parameters of the through-holes to be processed on the PCB to be processed, to obtain the target back-drilled through-holes, including:

[0098] S701: Determine the back drilling depth based on the target thickness and the parameters of the PCB to be processed.

[0099] S702: Based on the back-drilling depth, control the drilling equipment to perform back-drilling on the through-holes of the PCB to be processed, and obtain the target back-drilled through-hole.

[0100] Back drilling depth refers to the depth to which the through hole to be machined needs to be back drilled.

[0101] As an example, in step S701, the back drilling depth can be determined based on the target thickness and the number of PCB layers and the PCB thickness in the parameters of the PCB to be processed.

[0102] As an example, in step S702, back drilling is performed on the through hole corresponding to the parameters of the through hole to be processed on the PCB to be processed, according to the back drilling depth, to obtain the target back drill through hole, thereby avoiding the impact of the target prepreg on the back drilling accuracy caused by the glue flow, and realizing high-precision control of back drilling.

[0103] This embodiment provides a back-drilling controller, a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the PCB back-drilling method described above.

[0104] This embodiment provides an automatic back drilling device, including the back drilling controller described above.

[0105] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A PCB back-drilling method, characterized in that, include: Obtain the PCB back drilling request corresponding to the PCB to be processed. The PCB back drilling request includes the through hole parameters to be processed, the PCB parameters to be processed, and the prepreg parameters corresponding to the target prepreg. Based on the parameters of the through hole to be processed and the parameters of the prepreg, the local flow region of the prepreg is determined; Based on the prepreg parameters and the PCB to be processed, the target thickness of the target prepreg within the local prepreg flow area is determined; Based on the parameters of the PCB to be processed, the target residual copper ratio of each PCB layer in the local prepreg flow area is determined. Based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio, the target thickness of the target prepreg within the local prepreg flow area is determined. Determine the back drilling depth based on the target thickness and the parameters of the PCB to be processed; Based on the back-drilling depth, the drilling equipment is controlled to perform back-drilling on the through-hole of the PCB to be processed, so as to obtain the target back-drilled through-hole.

2. The PCB back drilling method as described in claim 1, characterized in that, The parameters of the through hole to be processed include the coordinates of the through hole to be processed; the parameters of the prepreg include the flow coefficient of the prepreg. The step of determining the local flow region of the prepreg based on the parameters of the through-hole to be processed and the parameters of the prepreg includes: The target flow area is determined based on the flow coefficient of the prepreg. Based on the coordinates of the through-hole to be processed and the target flow area, the local semi-cured sheet flow region centered on the coordinates of the through-hole to be processed is determined.

3. The PCB back drilling method as described in claim 1, characterized in that, The prepreg parameters include the initial prepreg thickness; the PCB parameters to be processed include the initial PCB thickness and the thickness of each metal layer. The determination of the target thickness of the target prepreg within the local prepreg flow area based on the prepreg parameters, the PCB parameters to be processed, and the target residual copper ratio includes: Detect the actual PCB thickness corresponding to the PCB to be processed; Based on the actual PCB thickness and the initial PCB thickness, the first calculation parameter is determined; Based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg, the second calculation parameter is determined. Based on the initial prepreg thickness, the first calculation parameter, and the second calculation parameter, the target thickness corresponding to the target prepreg in the PCB to be processed is determined.

4. The PCB back drilling method as described in claim 3, characterized in that, The step of determining the first calculation parameter based on the actual PCB thickness and the initial PCB thickness includes: determining a thickness difference based on the actual PCB thickness and the initial PCB thickness, and determining the quotient between the thickness difference and the initial PCB thickness as the first calculation parameter.

5. The PCB back drilling method as described in claim 3, characterized in that, The determination of the second calculation parameter based on the metal layer thickness and target residual copper ratio corresponding to each metal layer in the target prepreg includes: The actual metal thickness of each metal layer is determined based on the metal layer thickness and target residual copper ratio of each metal layer in the target prepreg. The sum of the actual metal thicknesses of two adjacent metal layers is determined as the first target parameter, and the sum of the actual metal thicknesses of all metal layers is determined as the second target parameter. The quotient of the first target parameter and the second target parameter is determined as the second calculation parameter.

6. A back-drilling controller, a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the PCB back-drilling method as described in any one of claims 1 to 5.

7. An automatic back drilling device, characterized in that, Includes the back drill controller as described in claim 6.

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