Laser processing method for Cavity blind groove of HDI plate and HDI plate

Abstract

The invention belongs to the technical field of printed circuit board manufacturing, and discloses a laser processing method for a Cavity blind groove of an HDI board and the HDI board. The method comprises the following steps: optimizing laser processing parameters; on the basis of a result obtained after laser processing parameter optimization, processing and cleaning process optimization is carried out; a combined process of plasma treatment and anti-welding super-roughening pretreatment is adopted to replace a traditional process of plasma treatment and anti-welding sand blasting pretreatment, and the micro-etching amount of super-roughening treatment is controlled; and processing the Cavity blind slot of the eight-layer second-order HDI board. According to the HDI plate Cavity blind groove machining micro-etching amount depth, the machining depth distance is shortened by 60%, the efficiency is improved by 150%, meanwhile, carbide residues at the bottom of the groove are remarkably reduced, the product yield and reliability are improved, and the method is suitable for machining HDI products with thin dielectric layers and small blind grooves.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of printed circuit board manufacturing, and particularly relates to a laser processing method for a cavity blind slot of an HDI board and the HDI board. BACKGROUND

[0002] With the development of electronic products towards miniaturization, light weight and high performance, advanced system-in-package (SiP) and high-density interconnection (HDI) boards are widely used. As a key manufacturing process, cavity technology realizes three-dimensional integration by processing blind slots in the printed circuit board and embedding components, which can reduce signal crosstalk and improve space utilization.

[0003] Through the above analysis, the problems and defects of the prior art are: at present, for the HDI product with thin dielectric layer and small blind slot size, CO2 laser or ultraviolet / green laser is usually used to process the cavity blind slot by layer-by-layer ablation. However, this process has obvious defects: first, the processing efficiency is low, and the layer-by-layer ablation leads to a long distance of 100 minutes between the single-sided board processing micro-etching depth and the processing depth, and the processing cost accounts for about 20% of the total cost; second, the quality of the slot bottom is poor, and there are generally carbon residues on the copper surface, with a defect rate close to 100%, which seriously affects the electrical performance and long-term reliability of the product. The existing post-processing cleaning methods such as sandblasting and film removal either cannot effectively remove the carbon residues or will significantly affect the copper thickness uniformity and line width consistency, which poses a quality risk. SUMMARY

[0004] To overcome the problems in the related art, the present application provides a laser processing method for a cavity blind slot of an HDI board and the HDI board.

[0005] The technical solution is as follows: the laser processing method for the cavity blind slot of the HDI board comprises the following steps:

[0006] S1, laser processing parameter optimization; a laser drilling machine is selected, and after the outer layer circuit is made, laser blind slot processing is performed on an eight-layer second-order HDI board; the laser hole overlapping rate is adjusted to reduce the number of laser processing, and the optimal parameter combination of pulse width and energy in laser processing is determined;

[0007] S2, based on the results of laser processing parameter optimization, the processing and cleaning process is optimized; an equal ion processing combined with a solder mask super-roughening pretreatment process is adopted to control the micro-etching amount of super-roughening processing;

[0008] S3, according to the control results, the cavity blind slot of the eight-layer second-order HDI board is processed.

[0009] In step S1, the laser via filling rate is adjusted, including: adjusting the laser via filling rate of 50% to 30%, keeping the laser aperture of 150μm unchanged, and reducing the number of laser processing to 4 million holes / panel.

[0010] In step S1, the optimal parameter combination is a pulse width of 1277 and an energy of 10mJ.

[0011] In step S2, plasma treatment is performed, including: initially removing impurities on the inner surface of the groove, and then removing carbide residues at the bottom of the groove through super roughening treatment, and controlling the micro-etching amount of the super roughening treatment to be stable at 0.85μm.

[0012] Furthermore, the method for controlling the micro-etching amount of the super roughening treatment includes:

[0013] Construct a logical processing depth distance calculation function between the standard micro-etching amount operating condition samples and the operating state data of the micro-etching amount control system to be detected;

[0014] Determine the logical processing depth distance threshold for determining system anomalies, that is, the safety domain attribution threshold, through training and learning with historical operation data, simulation calculations, or verification of micro-etching amount operation anomaly data samples collected, and detect system anomalies or retrieve abnormal situations in the system's historical operation data.

[0015] Furthermore, the method for constructing the standard micro-etching amount operating condition samples includes: selecting single-mode standard conditions by combining two strategies of simulation tests and data analysis;

[0016] The simulation test includes using the full-range simulator supporting the laser drilling machine to operate the system state according to the typical operating condition parameters as the standard state;

[0017] Data analysis includes calculating the logical processing depth distance between all operation data samples under a certain operation condition in the sample based on the system's historical operation data, and finding an operation data sample instance with the smallest sum of processing depth distances from all other operation data samples as the standard micro-etching amount operating condition sample representing this operation condition, that is, the operation mode, or calculating the logical center of the data sample set in the operation area as the standard micro-etching amount operating condition.

[0018] Furthermore, the standard micro-etching amount operating condition system includes: laser steady-state operation type conditions, different sub-board switching type conditions, and start / stop laser drilling machine type conditions;

[0019] Each operation condition is an operation mode, corresponding to an operation domain and a standard micro-etching amount operating condition;

[0020] The laser steady-state operation type conditions include different sub-board traveling one, traveling two, traveling three... traveling N conditions;

[0021] Different subboard switching conditions include switching from traveling M to traveling L, where M≠L and M,L∈(1,2…N);

[0022] Starting / stopping laser drilling machines includes cold start (physical start), hot start, normal shutdown of laser drilling machines, and emergency shutdown of laser drilling machines.

[0023] The five characteristic parameters characterizing the operating status include: adjusting the laser stacking rate to 30%, keeping the laser aperture constant at 150μm, and reducing the number of laser processing holes to 4 million holes / panel; the optimal parameter combination is a pulse width of 1277 and an energy of 10mJ.

[0024] Furthermore, the method for constructing the logical processing depth distance calculation function includes:

[0025] The logic processing depth distance calculation function is used as a metric function to quantitatively analyze the proximity of logical relationships between different stable operating states of the system; including the logic processing depth distance calculation function for steady-state power operation conditions as well as the logic processing depth distance calculation function for starting and stopping laser drilling and transient processes of operating condition switching;

[0026] (1) Calculation function for logical processing depth distance under steady-state power operation: A weighted Euclidean processing depth distance algorithm is used to calculate the logical processing depth distance between steady-state systems, as follows:

[0027] During steady-state power operation, the two multi-dimensional vectors for calculating the logical processing depth distance are:

[0028] F = [f1, f2, f3, f4, f5]

[0029] L = [l1, l2, l3, l4, l5]

[0030] In the formula, F is the machining depth, L is the machining length, fi is the machining depth under the i-th feature parameter, and li is the machining length under the i-th feature parameter;

[0031] The corresponding weight vector is:

[0032] E = [e1, e2, e3, e4, e5]

[0033] e1 + e2 + ... + e5 = 100

[0034] In the formula, E is the weight vector value corresponding to the logical processing depth distance, and ei is the weight vector obtained under the i-th feature parameter;

[0035] The defined weighted Euclidean machining depth distance calculation function is:

[0036]

[0037] In the formula, d FE This is a weighted Euclidean machining depth distance value;

[0038] (2) Logical processing depth distance calculation function for starting and stopping laser drilling and transient process of switching working conditions:

[0039] The feature vector used to calculate the depth distance of the logic processing in the running state is represented as:

[0040] F=[f1,f2,f3,f4,f5,f1′,f2′,f3′,f4′,f5′]

[0041] L=[l1,l2,l3,l4,l5,l1′,l2′,l3′,l4′,l5′]

[0042] In the formula, fi′ is the logical processing depth distance of the switching transient process under the i-th feature parameter, and li′ is the logical processing length distance of the switching transient process under the i-th feature parameter;

[0043] The corresponding weight vector is:

[0044] E=[e1,e2,e3,e4,e5,e1′,e2′,e3′,e4′,e5′]

[0045] e1 + e2 + ... + e5 = 100

[0046] e1′+e2′+e3′,…,+e5′=100

[0047] For the transient operation process, the logic processing depth distance is defined by two calculation functions: the characteristic parameter logic processing depth distance and the characteristic parameter change rate, i.e., the differential logic processing depth distance, as shown below:

[0048]

[0049] In the formula, d′ FE The rate of change of the characteristic parameters is the differential logic processing depth distance.

[0050] Furthermore, after obtaining the coordinates of the standard micro-etching target, the actual micro-etching depth distance is calculated from the coordinates of all sub-board nodes in each working condition. This distance is then compared with the micro-etching control depth distance to determine each error.

[0051] The error calculation method is shown in the following formula:

[0052]

[0053] In the formula, (x i ,y i ,z i ),(x i′,y i ′,z i ′) represent the distance coordinates of the micro-etching depth control machining depth and the distance coordinates of the actual micro-etching depth machining depth for the i-th sub-board, respectively, δ i The error between the micro-etching depth control machining depth distance coordinate and the actual micro-etching depth distance coordinate is defined by δ, which is the mean of all sub-board errors, and n is the number of errors.

[0054] Another object of the present invention is to provide an HDI board, which is manufactured using a laser processing method for Cavity blind grooves of the HDI board.

[0055] Combining all the above technical solutions, the beneficial effects of this invention are as follows:

[0056] This method addresses the technical problems of low processing efficiency and excessive carbide residue at the bottom of the tank in existing laser layer-by-layer ablation processes by optimizing laser processing parameters and improving the post-processing cleaning procedure. Specifically, the laser perforation rate is adjusted to 30%, a specific combination of pulse width and energy parameters is used, and the post-processing cleaning method is changed from sandblasting to ultra-roughening treatment. After implementation, the micro-etching amount in HDI board cavity blind trench processing is reduced by 60%, efficiency is increased by 150%, and carbide residue at the bottom of the tank is significantly reduced, improving product yield and reliability. It is suitable for processing HDI products with thin dielectric layers and small blind trench sizes.

[0057] Therefore, in response to the technical problems of low processing efficiency, high carbide residue at the bottom of the groove, and poor post-processing cleaning effect in the existing laser processing technology for HDI board cavity blind grooves, this invention provides a high-efficiency laser processing method that balances efficiency and quality. Attached Figure Description

[0058] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure;

[0059] Figure 1 This is a flowchart of the laser processing method for HDI board cavity blind grooves provided in an embodiment of the present invention;

[0060] Figure 2 This is a schematic diagram of existing technology with stacked holes;

[0061] Figure 3 This is a schematic diagram of the stacked holes of the present invention;

[0062] Figure 4 This is a schematic diagram of the Cavity blind slot type involved in the present invention;

[0063] Figure 5 A schematic diagram of an eight-layer second-order HDI board stack fabricated using the method of the present invention;

[0064] Figure 6 The image shows the effect of an eight-layer second-order HDI board processed using the method of the present invention. Detailed Implementation

[0065] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0066] Example 1: The laser processing method for HDI board cavity blind grooves provided in this embodiment of the invention uses laser processing instead of the traditional processing mode for thin dielectric and small blind groove HDI boards.

[0067] The innovative laser stacking hole processing method improves processing accuracy and production efficiency, reduces carbides, and lowers production costs.

[0068] An optimized process is adopted: after the outer layer laser blind groove is processed, plasma treatment combined with anti-weld ultra-roughening pretreatment process is used to further solve the problem of carbon residue and achieve high product quality.

[0069] The core idea of ​​this invention is to improve material removal efficiency by optimizing laser processing parameters, and at the same time improve the post-processing cleaning process, so as to reduce carbide residue and control the impact on the plate structure.

[0070] like Figure 1 Specifically, it includes the following steps:

[0071] S1, Laser processing parameter optimization; A laser drilling machine was selected for an eight-layer second-order HDI board. Laser blind slot processing was performed after the outer layer circuitry was completed. The laser stacking rate was adjusted to reduce the number of laser processing operations and to determine the optimal combination of pulse width and energy parameters in laser processing.

[0072] For example, the traditional 50% laser hole stacking ratio is adjusted to 30%, while keeping the laser aperture at 150μm, reducing the number of laser-processed holes to 4 million holes / panel. Simultaneously, the optimal parameter combination is determined to be a pulse width of 1277 and an energy of 10mJ. This parameter combination can significantly improve the material removal rate while ensuring processing accuracy, as shown in Table 1. Figure 2 This is a schematic diagram of existing technology with stacked holes. Figure 3 This is a schematic diagram of the stacked holes of the present invention;

[0073] Table 1. Optimized laser processing parameters of the present invention and parameters of existing technologies.

[0074] Status Laser aperture Stacking rate Laser number Processing time Original parameters 150 pm 50％ 7.5 million holes / pnl 100 min / pnl Optimized parameters 150 pm 30％ 4 million holes / pnl 40 min / pnl

[0075] S2. Based on the optimized results of laser processing parameters, optimize the processing cleaning process; adopt a combined process of plasma treatment and pretreatment of solder mask ultra-roughening, and control the micro-etching amount of the ultra-roughening treatment.

[0076] Among them, the plasma treatment first preliminarily removes impurities on the inner surface of the groove, and then removes the carbide residue at the bottom of the groove through the ultra-roughening treatment, and controls the micro-etching amount of the ultra-roughening treatment to be stable at 0.85 μm, so as to avoid excessive influence on the copper thickness and line width.

[0077] Exemplarily, the method for controlling the micro-etching amount of the ultra-roughening treatment includes:

[0078] Construct a logical processing depth distance calculation function between the standard micro-etching amount operating condition samples and the operating state data of the micro-etching amount control system to be detected.

[0079] Determine the logical processing depth distance threshold for determining system abnormality, that is, the safety domain attribution threshold, through training and learning with historical operation data, simulation calculation or verification of the micro-etching amount operation abnormal data samples collected, and detect system abnormalities or retrieve abnormal situations in the system historical operation data.

[0080] The method for constructing the standard micro-etching amount operating condition system includes: selecting single-mode standard conditions by combining two strategies of simulation test and data analysis.

[0081] The simulation test includes using the full-range simulator supporting the laser drilling machine to operate the system state according to the typical operating condition parameters as the standard state.

[0082] Data analysis includes calculating and obtaining the logical processing depth distance between all operation data samples under a certain operation condition in the sample based on the system historical operation data, and finding an operation data sample instance with the smallest sum of processing depth distances from all other operation data samples as the standard micro-etching amount operating condition sample representing this operation condition, that is, the operation mode, or calculating the logical center of the data sample set in the operation area as the standard micro-etching amount operating condition.

[0083] The standard micro-etching amount operating condition system includes: laser steady-state operation type conditions, different sub-board switching type conditions, and start / stop laser drilling machine type conditions.

[0084] Each of the above operation conditions is an operation mode, corresponding to an operation domain and a standard micro-etching amount operating condition.

[0085] The laser steady-state operation type conditions include different sub-board traveling one, traveling two, traveling three... traveling N conditions.

[0086] The different sub-board switching conditions include switching from traveling M to traveling L, where M≠L and M,L∈(1,2…N);

[0087] The start / stop laser drilling machine operation conditions include cold start (physical start), hot start, normal stop of laser drilling machine, and emergency stop of laser drilling machine.

[0088] The five characteristic parameters characterizing the operating status include: adjusting the laser stacking rate to 30%, keeping the laser aperture constant at 150μm, and reducing the number of laser processing holes to 4 million holes / panel; the optimal parameter combination is a pulse width of 1277 and an energy of 10mJ.

[0089] The method for constructing the logical processing depth distance calculation function includes:

[0090] The logic processing depth distance calculation function is used as a metric function to quantitatively analyze the proximity of logical relationships between different stable operating states of the system; including the logic processing depth distance calculation function for steady-state power operation conditions as well as the logic processing depth distance calculation function for starting and stopping laser drilling and transient processes of operating condition switching;

[0091] (1) Calculation function for logical processing depth distance under steady-state power operation: A weighted Euclidean processing depth distance algorithm is used to calculate the logical processing depth distance between steady-state systems, as follows:

[0092] During steady-state power operation, the two multi-dimensional vectors for calculating the logical processing depth distance are:

[0093] F = [f1, f2, f3, f4, f5]

[0094] L = [l1, l2, l3, l4, l5]

[0095] In the formula, F is the machining depth, L is the machining length, fi is the machining depth under the i-th feature parameter, and li is the machining length under the i-th feature parameter;

[0096] The corresponding weight vector is:

[0097] E = [e1, e2, e3, e4, e5]

[0098] e1 + e2 + ... + e5 = 100

[0099] In the formula, E is the weight vector value corresponding to the logical processing depth distance, and ei is the weight vector obtained under the i-th feature parameter;

[0100] The defined weighted Euclidean machining depth distance calculation function is:

[0101]

[0102] In the formula, d FE This is a weighted Euclidean machining depth distance value;

[0103] (2) Logical processing depth distance calculation function for starting and stopping laser drilling and transient process of switching working conditions:

[0104] The feature vector used to calculate the depth distance of the logic processing in the running state is represented as:

[0105] F=[f1,f2,f3,f4,f5,f1′,f2′,f3′,f4′,f5′]

[0106] L=[l1,l2,l3,l4,l5,l1′,l2′,l3′,l4′,l5′]

[0107] In the formula, fi′ is the logical processing depth distance of the switching transient process under the i-th feature parameter, and li′ is the logical processing length distance of the switching transient process under the i-th feature parameter;

[0108] The corresponding weight vector is:

[0109] E=[e1,e2,e3,e4,e5,e1′,e2′,e3′,e4′,e5′]

[0110] e1 + e2 + ... + e5 = 100

[0111] e1′+e2′+e3′,…,+e5′=100

[0112] For the transient operation process, the logic processing depth distance is defined by two calculation functions: the characteristic parameter logic processing depth distance and the characteristic parameter change rate, i.e., the differential logic processing depth distance, as shown below:

[0113]

[0114] In the formula, d′ FE The rate of change of the characteristic parameters is the differential logic processing depth distance.

[0115] After obtaining the coordinates of the standard micro-etching target, the actual micro-etching depth distance is calculated from the coordinates of all sub-board nodes in each working condition. This distance is then compared with the micro-etching control depth distance to determine each error.

[0116] The error calculation method is shown in the following formula:

[0117]

[0118] In the formula, (x i ,y i ,z i ),(x i ′,yi ′,z i ′) represent the distance coordinates of the micro-etching depth control machining depth and the distance coordinates of the actual micro-etching depth machining depth for the i-th sub-board, respectively, δ i The error between the micro-etching depth control machining depth distance coordinate and the actual micro-etching depth distance coordinate is defined by δ, which is the mean of all sub-board errors, and n is the number of errors.

[0119] S3, based on the control results, perform Cavity blind groove processing on an eight-layer second-order HDI board.

[0120] As can be seen from the above implementation, the processing efficiency is significantly improved: by optimizing the laser stacking rate and parameter combination, the processing time for micro-etching depth of blind grooves on single-panel panels is shortened from 100 minutes to 40 minutes, with an efficiency increase of 150% and a significant reduction in processing costs.

[0121] Significantly improved tank bottom quality: The use of an ultra-coarsening post-processing procedure effectively solves the problem of carbide residue. Visual inspection results show that only a very small number of panels have slight residue, and the number of residues has been reduced from 10-30 pcs / panel to 3-5 pcs / panel, resulting in a significant improvement in product yield.

[0122] High processing stability: The micro-etching amount of the ultra-roughening treatment is stable and controllable, and the impact on copper thickness uniformity and line width consistency is controlled within an acceptable range, avoiding the quality risks caused by the film removal process and improving the long-term reliability of the product.

[0123] Example 2: The present invention provides an HDI board processed by a laser processing method for creating a Cavity blind groove in an HDI board.

[0124] The schematic diagram of the Cavity blind slot type involved in this invention is shown below. Figure 4 A schematic diagram of an eight-layer second-order HDI board stack fabricated using the method of this invention is shown below. Figure 5 Product renderings as follows Figure 6 .

[0125] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention and within the spirit and principles of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A laser processing method for cavity blind grooves on HDI boards, characterized in that, The method includes the following steps: S1. Optimization of laser processing parameters: Select a laser drilling machine. For an eight-layer second-order HDI board, after the outer layer circuit production is completed, laser blind vias are processed. Adjust the laser via stacking rate to reduce the number of laser processing operations, and determine the optimal parameter combination of pulse width and energy in laser processing. S2. Based on the results of the optimized laser processing parameters, optimize the processing and cleaning process: Adopt a combined process of plasma treatment and pre-treatment of solder mask super roughening to control the micro-etching amount of the super roughening treatment. S3. According to the regulation results, perform Cavity blind via processing on the eight-layer second-order HDI board.

2. The laser processing method for HDI board cavity blind grooves according to claim 1, characterized in that, In step S1, the adjustment of the laser via stacking rate includes: adjusting the laser via stacking rate of 50% to 30%, keeping the laser aperture of 150 μm unchanged, and reducing the number of laser processing operations to 4 million holes / panel.

3. The laser processing method for HDI board cavity blind grooves according to claim 1, characterized in that, In step S1, the optimal parameter combination is a pulse width of 1277 and an energy of 10 mJ.

4. The laser processing method for HDI board cavity blind grooves according to claim 1, characterized in that, In step S2, the plasma treatment includes: initially removing impurities on the inner surface of the via, and then removing carbide residues at the bottom of the via through super roughening treatment, and controlling the micro-etching amount of the super roughening treatment to be stable at 0.85 μm.

5. The laser processing method for HDI board cavity blind grooves according to claim 4, characterized in that, The method for controlling the micro-etching amount of the super roughening treatment includes: Construct a logical processing depth distance calculation function between the standard micro-etching amount operating condition samples and the operating state data of the micro-etching amount control system to be detected. Determine the logical processing depth distance threshold for determining system anomalies, that is, the safety domain attribution threshold, through training and learning with historical operation data, simulation calculations, or verification of abnormal data samples of the micro-etching amount collected, and detect system anomalies or retrieve abnormal conditions in the system's historical operation data.

6. The laser processing method for HDI board cavity blind grooves according to claim 5, characterized in that, The method for constructing the standard micro-etching amount operating condition samples includes: selecting single-modal standard conditions by combining two strategies of simulation tests and data analysis. The simulation test includes using the full-range simulator supporting the laser drilling machine to operate the system state according to the typical operating condition parameters as the standard state. Data analysis includes calculating the logical processing depth distance between all operating data samples under a certain operating condition in the sample based on the system's historical operation data, and finding an operating data sample instance with the smallest sum of processing depth distances from all other operating data samples as the standard micro-etching amount operating condition sample representing this operating condition, that is, the operating mode, or calculating the logical center of the data sample set in the operating area as the standard micro-etching amount operating condition.

7. The laser processing method for HDI board cavity blind grooves according to claim 4, characterized in that, The standard micro-etching amount operating condition system includes: laser steady-state operating conditions, different sub-board switching conditions, and start / stop laser drilling machine conditions. Each operating condition is an operating mode, corresponding to an operating domain and a standard micro-etching amount operating condition. The laser steady-state operating conditions include different sub-board traveling conditions such as traveling one, traveling two, traveling three... traveling N. The different sub-board switching conditions include traveling M switching to traveling L, where M≠L and M, L∈(1, 2... N). The start / stop laser drilling machine conditions include cold start, that is, physical start, warm start, normal stop of the laser drilling machine, and emergency stop of the laser drilling machine conditions. The five characteristic parameters characterizing the operating status include: adjusting the laser stacking rate to 30%, keeping the laser aperture constant at 150μm, and reducing the number of laser processing holes to 4 million holes / panel; the optimal parameter combination is a pulse width of 1277 and an energy of 10mJ.

8. The laser processing method for HDI board cavity blind grooves according to claim 4, characterized in that, The method for constructing the logical processing depth distance calculation function includes: The logic processing depth distance calculation function is used as a metric function to quantitatively analyze the proximity of logical relationships between different stable operating states of the system; including the logic processing depth distance calculation function for steady-state power operation conditions as well as the logic processing depth distance calculation function for starting and stopping laser drilling and transient processes of operating condition switching; (1) Calculation function for logical processing depth distance under steady-state power operation: A weighted Euclidean processing depth distance algorithm is used to calculate the logical processing depth distance between steady-state systems, as follows: During steady-state power operation, the two multi-dimensional vectors for calculating the logical processing depth distance are: F = [f1, f2, f3, f4, f5] L＝[l1,l2,l3,l4,l5] In the formula, F is the machining depth, L is the machining length, fi is the machining depth under the i-th feature parameter, and li is the machining length under the i-th feature parameter; The corresponding weight vector is: E = [e1, e2, e3, e4, e5] e1 + e2 + ... + e5 = 100 In the formula, E is the weight vector value corresponding to the logical processing depth distance, and ei is the weight vector obtained under the i-th feature parameter; The defined weighted Euclidean machining depth distance calculation function is: In the formula, d FE This is a weighted Euclidean machining depth distance value; (2) Logical processing depth distance calculation function for starting and stopping laser drilling and transient process of switching working conditions: The feature vector used to calculate the depth distance of the logic processing in the running state is represented as: F=[f1,f2,f3,f4,f5,f1′,f2′,f3′,f4′,f5′] L＝[l1,l2,l3,l4,l5,l1′,l2′,l3′,l4′,l5′] In the formula, fi′ is the logical processing depth distance of the switching transient process under the i-th feature parameter, and li′ is the logical processing length distance of the switching transient process under the i-th feature parameter; The corresponding weight vector is: E=[e1,e2,e3,e4,e5,e1′,e2′,e3′,e4′,e5′] e1 + e2 + ... + e5 = 100 e1′+e2′+e3′,…,+e5′=100 For the transient operation process, the logic processing depth distance is defined by two calculation functions: the characteristic parameter logic processing depth distance and the characteristic parameter change rate, i.e., the differential logic processing depth distance, as shown below: In the formula, d′ FE The rate of change of the characteristic parameters is the differential logic processing depth distance.

9. The laser processing method for HDI board cavity blind grooves according to claim 4, characterized in that, After obtaining the coordinates of the standard micro-etching target, the actual micro-etching depth distance is calculated from the coordinates of all sub-board nodes in each working condition. This distance is then compared with the micro-etching control depth distance to determine each error. The error calculation method is shown in the following formula: In the formula, (x i ,y i ,z i ),(x′ i ,y′ i ,z′ i ) represent the distance coordinates of the micro-etching depth control machining depth and the distance coordinates of the actual micro-etching depth machining depth for the i-th sub-board, respectively, δ i The error between the micro-etching depth control machining depth distance coordinate and the actual micro-etching depth distance coordinate is defined by δ, which is the mean of all sub-board errors, and n is the number of errors.

10. An HDI board, characterized in that, It is manufactured using the laser processing method for the HDI board cavity blind groove as described in any one of claims 1-9.

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