Method for manufacturing halogen-free high-density interconnection multilayer circuit board

Abstract

The application discloses a preparation method of a halogen-free high-density interconnection multilayer circuit board and relates to the technical field of high-density interconnection multilayer circuit board manufacturing. According to material batches and target accumulation levels, a production board is associated with a same-batch witness sheet group comprising physically independent hole-forming parallel sub-sheets, drill-dirt-removing parallel sub-sheets and metalizing hole-filling parallel sub-sheets. Hole-forming windows, drill-dirt-removing windows and metalizing and hole-filling windows are sequentially established, and hole-forming gating, interface gating and metalizing hole-filling gating are performed. A next-stage parallel sub-sheet reestablishes a cumulative previous state according to a passed upstream process window. After each gating passes, the production board enters a corresponding downstream process. When the upstream process window changes, downstream windows and gating evidences formed by the upstream process window stop being used for release. The parallel sub-sheets are sealed after destructive detection and no longer circulate. The production board circulation can be blocked before an abnormal interface is covered by subsequent processing, and phased reviewable evidences are reserved.

Description

Technical Field

[0001] This invention relates to the field of high-density interconnect multilayer circuit board manufacturing technology, specifically to a method for preparing halogen-free high-density interconnect multilayer circuit boards. Background Technology

[0002] High-density interconnect multilayer circuit boards are used in electronic devices with high wiring density and interlayer interconnect requirements. Current manufacturing typically involves stacking dielectric and copper layers on a core board or the previous layer, followed by sequential micro-blind via formation, hole bottom cleaning, metallization, via filling, pattern transfer, and outer layer inspection after lamination. The resin system, filler, moisture content, curing thickness, and copper surface condition of the halogen-free laminated dielectric can all affect the process response.

[0003] Chinese patent document CN115494372A discloses a method for quality testing and monitoring of HDI blind via reliability. This method involves setting a matrix of blind vias on the top and bottom layers of a high-density interconnect board and routing them to form a chain of blind vias. Simultaneously, test pin points, test fixing holes, and through-holes connecting the two sides of the via chain are set. After the circuit board is processed to the outer layer etching stage, a high-current tester consisting of a voltage and current regulator, a temperature sensor, a micro-resistance tester, and a timer is used to heat the blind via chain, recording the initial resistance, maximum resistance, and resistance change rate, and outputting test curves at time intervals. When the resistance change rate exceeds a judgment threshold, the corresponding product is intercepted and sliced ​​for analysis to evaluate the reliability of the blind via electrical interconnect.

[0004] The aforementioned method can identify some blind via reliability anomalies based on changes in subsequent resistance values. However, its detection targets are mainly boards with already formed blind via chains and outer layer circuit structures, and the detection results focus on comprehensive reliability judgment. In sequential build-up manufacturing, laser drilling, desmearing, seed layer formation, and via-filling plating continuously change the via walls, via bottoms, and capture pad interfaces. Changes in material batches, cumulative thermal history, or curing medium thickness can also alter the responses of each process. Early anomalies such as unopened via bottoms, capture pad erosion, and thin layer residue at the via bottom may be partially altered or covered by subsequent processing, while cross-sectional inspection usually destroys the inspected sample. Therefore, although subsequent resistance anomalies or the final cross-section can indicate the presence of defects, it may be difficult to accurately determine the initiating process and its corresponding conditions, increasing the uncertainty in process adjustments, batch handling, and in-process board release decisions.

[0005] Therefore, it is still necessary to solve the problem of how to ensure that the test results of each process accurately correspond to the actual interface state under the specific material batch and target layer level, and to complete the identification and handling of anomalies before they are covered by subsequent processing. Summary of the Invention

[0006] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a method for fabricating halogen-free high-density interconnect multilayer circuit boards. This method sequentially establishes via windows, de-drilling windows, and metallization and via-filling windows, and performs via gating, interface gating, and metallization / via-filling gating. Subsequent parallel sub-wafers reconstruct the accumulated preceding states based on the passed upstream process windows. Only after each gating is passed does the production board enter the corresponding downstream process. When the upstream process window changes, the downstream windows and gating evidence formed by them cease to be used for release. This method can block the flow of production boards before abnormal interfaces are covered by subsequent processing, and retains verifiable evidence at different stages. This solves the technical problems described in the background art.

[0007] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: A method for fabricating a halogen-free high-density interconnect multilayer circuit board includes: Establish the relationship between production boards, material batches, target stacking layers, and witness sheet groups in the same batch. Witness sheet groups in the same batch include physically independent parallel test units for hole forming, parallel test units for de-drilling contamination, and parallel test units for metallization filling. Using each parallel test unit, a hole-forming window, a drill fouling removal window, and a metallization and hole-filling window are established sequentially, and hole-forming gating, interface gating, and metallization and hole-filling gating are executed respectively. The subsequent parallel test unit reconstructs the cumulative preceding state according to all the upstream process windows that have been passed. After each gate is passed, the production board will proceed to the corresponding hole drilling, desmearing, metallization and hole filling processes according to the corresponding process window; when the upstream process window changes, the downstream window and gate evidence formed by the process window will stop being used for release. Parallel test units undergoing destructive testing are sealed and not transferred to the next stage. If any gate fails, the production board is isolated before the corresponding downstream process.

[0008] Furthermore, the parallel test unit for hole forming, the parallel test unit for removing drilling debris, and the parallel test unit for metallization filling are respectively the parallel sub-pieces for hole forming, the parallel sub-pieces for removing drilling debris, and the parallel sub-pieces for metallization filling. The production board and the three parallel sub-sheets use the same halogen-free lamination medium batch and the outer copper layer batch and correspond to the same target lamination level. They also meet at least one of the same lamination load conditions and verified equivalent thermal history conditions. The equivalent thermal history is jointly defined by peak temperature, effective heat preservation time, heating and cooling process, board position type and post-curing thickness.

[0009] Furthermore, the hole-forming window and the de-drilling window are determined by continuous qualified parameter areas in the parameter space composed of at least two candidate factors; the combination of discrete candidate factors with only one difference of a preset level and the other candidate factors being the same is determined as an adjacent combination; for continuous candidate factors, the adjacent relationship is determined according to the step size or grid spacing determined before the experiment. A corresponding process window is formed only when multiple adjacent combinations meet the pre-fixed measurement fields, sampling locations, sample quantities, single sample limits, and statistical control limits. Isolated qualified combinations do not form a corresponding process window.

[0010] Furthermore, the metallized via-filling parallel sub-plate includes a physically separable metallization verification sub-region and a via-filling verification sub-region, and the two sub-regions reconstruct the previous state according to the hole-forming window and the de-drilling window; The metallization sub-window is determined based on the seed layer continuity detection results of the metallization verification sub-region, and the metallization verification sub-region is sealed after detection. When the metallization sub-window passes, the well filling verification sub-region reforms the seed layer according to the metallization sub-window and performs well filling verification; when the metallization sub-window fails, the well filling verification sub-region does not enter the main filling. When the hole filling verification passes, a hole filling sub-window is formed, which together with the metallization sub-window forms the metallization and hole filling windows; when the hole filling verification fails, no metallization and hole filling windows are formed.

[0011] Furthermore, the same batch of witness test pieces adopts at least one of the following: the same production panel edge partitioning setup and the independent accompanying test panel setup; when the panel edge partitioning setup is adopted, each parallel test unit is distinguished from each other by at least one of the following: cutting groove, separable connecting bridge, reserved partition boundary line, and hole array with independent boundary, and destructive sample preparation operation does not enter the reserved boundary of other parallel test units; When using an independent accompanying test plate, the independent accompanying test plate satisfies at least one of the same lamination load conditions and verified equivalent thermal history conditions.

[0012] (III) Beneficial Effects This invention provides a method for fabricating a halogen-free high-density interconnect multilayer circuit board, which has the following beneficial effects: By establishing traceable relationships between production boards, material batches, target lamination levels, lamination loads, and witness sheets within the same batch, gating results are made applicable only to boards whose material source corresponds to the thermal history of the lamination, avoiding erroneous application of process windows across batches or laminations. By setting physically independent parallel sub-sheets for hole forming, drilling smudge removal, and metallization filling, subsequent sub-sheets reconstruct the accumulated preceding state according to the upstream process windows they have passed. Sub-sheets that have undergone destructive testing are sealed and no longer circulated, preserving the true preceding state of the downstream process.

[0013] The production board is released in stages by controlling via hole gating, interface gating, and metallization filling gating. If a gate fails, the production board is isolated before the downstream process, preventing unopened hole bottoms, pad erosion, hole bottom residue, and dielectric damage from being covered by subsequent metal. By forming a continuous qualified parameter zone with multiple adjacent qualified combinations, and jointly judging according to pre-fixed measurement fields, sampling locations, sample quantities, and judgment limits, isolated combinations of occasional qualified results are excluded, allowing the process window to adapt to differences in material thickness, equipment fluctuations, and board surface position.

[0014] By dividing the parallel sub-sheets for metallized via filling into metallization verification sub-regions and via filling verification sub-regions, the continuity of the seed layer is verified first. Then, the pre-metallization state is reconstructed in the complete sub-region, and via filling verification is implemented, thus revealing seed layer discontinuities and via filling condition mismatches. When the upstream process window changes, the downstream window and gating evidence that depend on it are stopped, and the association and gating are re-established for subsequent target stacking layers. Combined with the process control terminal or controlled paper process card storing window versions, test results, and isolation status, anomaly verification has traceable evidence. Attached Figure Description

[0015] Figure 1 This is a flowchart illustrating the overall process of fabricating a halogen-free high-density interconnect multilayer circuit board and implementing three-level gating in this invention. Figure 2 This is a schematic diagram illustrating the batch-level physical relationship between the production board and the parallel witness chip of this invention. Figure 3 This is a schematic diagram of the laminated structure, micro-blind holes, and hole shape measurement of the present invention; Figure 4 This is a schematic diagram of the hole-forming window W1 and G1 hole-forming gating of the present invention; Figure 5 This is a schematic diagram of the gating interface between the drilling debris removal windows W2 and G2 of the present invention; Figure 6 This is a schematic diagram of continuous metallization, via filling, and G3 metallization via filling gating of the present invention; Figure 7 This is a diagram illustrating an embodiment of the process control terminal and virtual device of the present invention; Figure 8 This is a schematic diagram of the multi-layer re-verification and global anomaly feedback of the present invention; Figure 9 This is a schematic diagram of the physical partitioning and destructive detection isolation of the parallel witness sub-chips of the present invention; Figure 10 This is a schematic diagram of the three-level gate control phased release and process unit coordination of the production board of the present invention. Detailed Implementation

[0016] 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.

[0017] Please see Figures 1-10 This invention provides a method for fabricating a halogen-free high-density interconnect multilayer circuit board.

[0018] High-density interconnect multilayer circuit boards are typically manufactured using a sequential stacking process. This involves stacking dielectric and copper layers on a core board with existing circuitry or on a previous stacked layer, laminating to form micro-blind vias, followed by desmearing, activation or seed layer formation, via filling plating, pattern transfer, and outer layer inspection. For boards using halogen-free stacked dielectrics, the resin system, filler, moisture content, curing thickness, and copper surface condition can all influence the response of laser removal, via cleaning, and metal deposition. The basic manufacturing chain and multi-node inspections after laser drilling, desmearing, and via filling can exist in existing solutions; however, in some control methods, the preceding state of samples at each node, their fate after destructive testing, and the phased release relationship of the production board are not strictly enforced. When material batches or the thermal history of the stacked layers change, unopened vias, eroded pads, or thin-layer residues formed upstream may still be covered by subsequent desmearing, copper plating, or thicker plating, making it difficult to identify the origin of the anomaly from the final appearance.

[0019] The technical problem addressed by this embodiment is to match the conditions for micro-blind hole formation, desmearing, and metallization filling with the corresponding material batches and target stacking levels without relying on post-production attribution, and to block downstream manufacturing when the upstream interface condition does not meet the release conditions, thereby preserving verifiable evidence for each process stage. This problem cannot be solved simply by adding one more inspection, because cross-sectional inspection is usually destructive; if the same sample is sliced ​​and sent to the next process, the integrity of the sample cannot be maintained, nor can it represent the true preceding state of the subsequent process.

[0020] This embodiment uses one material batch and one target lamination level for the production board 100, and configures a witness sheet group 110 for the same batch. Within the witness sheet group 110, three independent parallel sub-sheets are set up: a hole-forming parallel sub-sheet 111, a drill-debris removal parallel sub-sheet 112, and a metallization-filling parallel sub-sheet 113. These three parallel sub-sheets respectively reproduce the cumulative pre-processing state that should exist before entering their respective tests. The hole-forming parallel sub-sheet 111 first determines the hole-forming window. And perform hole gating ; Only after passing the test will the production board 100 be manufactured. Hole formation, and isolation before descaling, while ensuring that the undamaged descaling parallel sub-plate 112 is pressed... A hole is formed. The descaling window is then determined by the descaling parallel sub-plate 112. And perform interface gating ; Only after passing the test will the production board 100 be manufactured. Remove drilling contaminants and isolate them before metallization, while simultaneously ensuring that the undamaged metallized through-hole parallel sub-plate 113 is aligned. Hole forming, pressing Remove drilling debris. Finally, the metallization and filling windows are determined by the metallization and filling parallel sub-plate 113. And perform metallization filling gating. ; Only after passing the test will the production board 100 be manufactured. Metallization and via filling. If the previous gate fails, production board 100 will not proceed to the corresponding downstream process, nor will it mask the upstream anomaly by increasing the intensity of downstream processing.

[0021] like Figure 1 As shown, steps S101 to S108 constitute a manufacturing closed loop bound to material batches and lamination levels. The lamination unit 200 forms the laminated production board 100 and the same batch of witness sheets 110; the laser drilling equipment 300, the de-drilling unit 400, and the metallization and filling unit 500 respectively perform actual physical processing; Detection unit 310 Detection unit 410 and The detection unit 510 provides observable results at each stage. The process control terminal 600 can receive measurement results, compare gating criteria, and output release or lockout status. Alternatively, it can use controlled paper process cards for recording and verification by the operator and another independent reviewer to achieve the same sequential constraints. Therefore, the process control terminal 600 is an optional control implementation; physical manufacturing actions such as lamination, hole drilling, desmearing, metallization, and hole filling are still performed by the corresponding process units.

[0022] Combination Figure 1 It is understood that the difference in the combination of this implementation method does not lie in the individual use of halogen-free materials, micro-blind holes, test units on the same production panel, multiple inspections, layer-by-layer hole bottom or hole filling inspections, nor in the individual use of experimental design to find continuous parameter regions, but in simultaneously establishing the following physical dependencies: the de-drilling parallel sub-plate 112 according to the currently passed Reconstruct the accumulated preceding state, and metallize the via-filling parallel sub-chip 113 according to the currently passed state. and Reconstruct the accumulated previous state; any sub-pieces or partitions that have undergone destructive sample preparation are sealed and not transferred to the next stage; each gating determines whether production board 100 can enter the corresponding next physical process; When changes occur, the original dependency is used. Formed , The evidence was no longer used for release. When changes occur, the original dependency is used. Formed Evidence is no longer used for release; and downstream processing is not used to compensate for upstream non-passage.

[0023] The values ​​given below are only for illustrating how to establish candidate windows around the baseline formulation and are not fixed production conditions; the specific window center, boundaries and release criteria can be determined based on material technical data, equipment capabilities, measurement systems and test results of witness tablet group 110 in the same batch.

[0024] Halogen-free means that the evaluated object meets applicable non-halogenated material specifications or customer specifications, and does not mean that the absolute content of all halogens is zero. For example, for copper-clad laminates or multilayer laminates, a material input with a chlorine content not exceeding 900 ppm, a bromine content not exceeding 900 ppm, and a combined chlorine content not exceeding 1500 ppm can be used, where ppm represents parts per million (ppm by mass). This judgment should clearly define the object being tested; copper-clad laminates, prepregs, multilayer films, solder resists, lettering materials, and adhesives should be evaluated separately according to their applicable specifications. The results of the substrate cannot be used to directly infer that all components of the finished board meet the same specifications.

[0025] High-density interconnect multilayer circuit boards refer to multilayer printed circuit boards that use sequential stacking and microvias to form high-density interlayer interconnections. This embodiment uses a rigid multilayer board with stacked micro-blind vias as the subject of this description; rigid-flex boards, packaging carriers, or other material systems can only adopt the corresponding implementation logic if their physical processes can meet the material batch-target stacking hierarchy association and parallel sub-chip gating relationship of this embodiment.

[0026] Production board 100 refers to a circuit board under manufacturing that carries the target circuit and undergoes lamination, hole drilling, desmearing, metallization, hole filling, and subsequent pattern processing in sequence. It can be a single board, a product unit in a production panel, or a group of boards with the same material batch-target layer hierarchy relationship.

[0027] The batch witness test panel group 110 refers to a group of test units that have a traceable relationship with the production panel 100 in terms of material batch, target lamination level, and specified critical process history. The batch witness test panel group 110 can be arranged on the edge of the same production panel, or it can be set as an independent accompanying test panel that accompanies the production panel 100 under the same lamination load, or it can be set as an accompanying test panel that is processed within the verified equivalent thermal history and process effective time range.

[0028] The hole-forming parallel sub-plate 111, the drill-debris-removing parallel sub-plate 112, and the metallized filling parallel sub-plate 113 are three independent test units in the same batch of witness sheet group 110; a reference retention sub-plate 114 can also be set up to retain the initial state after lamination, and a separate reliability test sample that is not mixed with the reference retention sub-plate 114 can also be set up. The hole-forming parallel sub-plate 111 is used for hole-forming gating. Verification, destructive testing, and sealing; de-drilling parallel sub-plate 112 first press Micro-blind holes are formed using the appropriate hole-forming conditions and then used for interface gating. Verification, destructive testing, and sealing; metallized through-hole parallel sub-chip 113 first presses... Through the hole-forming conditions and The descaling conditions are used to form the corresponding preceding state, which is then used for metallization and filling gating. The metallized via-filling parallel sub-plate 113 can also be physically divided into a metallized verification sub-region 113a and a via-filling verification sub-region 113b: the metallized verification sub-region 113a is used for pre-testing of the seed layer and is sealed after undergoing destructive testing; the via-filling verification sub-region 113b is used for verification of the passed... , and The accumulated preceding state is re-established and then used for well filling verification. The term "parallel" means that each sub-slice or physically separable sub-region reproduces the corresponding identical preceding conditions before entering its respective test, rather than continuously transferring the same sliced ​​sample.

[0029] A material batch refers to a group of critical media and copper surface materials that can be distinguished by supplier batch number, incoming material batch number, or equivalent controlled identifier. A target lamination level refers to a specific lamination round that will form micro-blind via interconnects after this round of lamination. Even if the material names are the same, different lamination levels may establish separate process windows due to differences in cumulative thermal history, curing medium thickness, or copper surface condition.

[0030] The same lamination load refers to the lamination of production board 100 and witness sheet group 110 in the same batch under the same controlled load in lamination unit 200. When using independent accompanying test boards, the same load can be replaced by a verified equivalent thermal history; equivalence can be defined by measurable fields such as peak temperature, effective holding time, heating and cooling process, board type, and post-curing thickness, rather than simply replacing it with production on the same day.

[0031] hole forming window This refers to a continuous qualified parameter zone formed near the laser reference formulation, targeting the current material batch and target build-up layer, that simultaneously meets the criteria for hole shape, hole bottom openness, and 150mm damage capture of the solder pad. (Drilling smudge removal window) It refers to When the corresponding preceding conditions are met, a continuous qualified processing area can simultaneously satisfy the criteria for hole bottom cleanliness, halogen-free deposited dielectric layer 130 damage, glass fiber condition, and captured pad 150 damage. Metallization sub-window This refers to the set of controlled conditions that can form a continuous seed layer 171; filling the hole window. It refers to After the corresponding metallization pre-conditioning is passed, the 172 cross-section of the through-hole filled copper meets the controlled condition set of the criterion. Metallization and through-hole filling window. Depend on and The verification is constrained by the order of metallization verification followed by via filling verification, rather than being a simple sum of the parameters of the two.

[0032] pore gating At least compare the top diameter, bottom diameter, depth, and aspect ratio of the vias to determine whether the bottom of the via exposes the capture pad (150) and the micro blind via (160). Bottom-to-top diameter ratio index Hole position offset And to capture erosion or thermal damage to pad 150. Interface gating. At least compare the following: bottom hole residue, resin shrinkage, glass fiber protrusion or erosion, halogen-free deposited dielectric layer 130 damage, and trapped pad 150 damage. Metallization fill gate. At least the continuous coverage of seed layer 171, voids and seams in via copper 172, via opening depressions, and via bottom interface separation are compared, and evaluation can be combined with copper thickness and resistance. The inputs for each gate include the identification of the corresponding parallel sub-chip, the previous process window version, measurement results, and applicable criteria. The outputs include pass, fail, or require review status. Only when the output is pass is the corresponding process window version recorded and the production board 100 allowed to proceed to the next physical process. The criteria for each gate are fixed before testing as measurement fields, sampling locations, sample quantities, single sample limits, and statistical control limits. Geometric limits and depression limits are preferentially taken from product drawings or procurement documents, material damage limits are preferentially taken from material compatibility tests, and copper thickness and resistance limits are preferentially taken from applicable inspection specifications. Criteria are not modified in reverse based on the sample distribution after testing.

[0033] The continuous qualified parameter zone refers to the area consisting of multiple adjacent qualified combinations within a parameter space composed of at least two candidate factors. For candidate factors set according to discrete levels, adjacent means that only one candidate factor differs from the other by one preset level, while the remaining candidate factors remain the same. For candidate factors set according to continuous variables, adjacent is determined according to the step size or grid spacing determined before the test. Although an isolated single point may satisfy one test, if all its adjacent combinations are unqualified, the single point is not directly identified as a stable process window. The continuous qualified parameter zone is used to reserve process margins for material thickness, equipment fluctuations, and differences in plate surface position. The prohibition of using downstream processes to compensate for upstream anomalies refers to: hole gating. If the test fails, surface opening is not achieved by extending or intensifying the descaling process; interface gating. If the process fails, do not extend the plating time, increase the copper thickness, or increase the filling current to cover any residue or dielectric damage at the bottom of the hole; if the seed layer 171 is discontinuous, do not use increased main filling current to replace the seed layer repair. This control principle prevents anomalies from being blocked at a still observable process stage, avoiding the difficulty in verifying the origin of the anomaly due to subsequent material coverage.

[0034] Anomaly-related process verification refers to identifying one or more potentially related process stages based on abnormal morphology or measurement results, and then confirming them through sample retesting, alternative applicable measurement methods, new parallel sub-samples, or univariate comparisons. Abnormal morphology is only used to trigger verification and is not directly used as the sole basis for determining a single responsible process.

[0035] To quantify and classify the aperture shape of micro-blind holes 160, an aspect ratio index is defined. The ratio of bottom diameter to top diameter index Their calculation relationships are as follows:

[0036]

[0037] In the formula, Indicates the depth of the hole. Indicates the apex diameter. Indicates the base diameter; , and Use the same unit of length, typically micrometers (μm), but the final unit should be consistent with the product drawings and measurement system; Reflects the ratio of hole depth to hole opening size. Both reflect the degree of contraction of the bottom of the hole relative to the opening, and are dimensionless quantities. Hole position offset. This indicates the distance between the central axis of the micro-blind via 160 and the central axis of the capture pad 150 projected onto the board surface. Adopted and , and The same unit of length. Wherein, the apex diameter is greater than 0.

[0038] The intensity of drilling fouling treatment can also be measured by changes in mass per unit area. The auxiliary evaluation is calculated as follows:

[0039] In the formula, This indicates the mass measured under specified drying and weighing conditions before descaling. This indicates the mass measured under the same drying and weighing conditions after the drilling debris removal treatment. This indicates the quality difference before and after processing; This indicates the predefined effective processing area. , and Using the same unit of mass, Using area units, The unit is a combination of mass and area. This only indicates the overall material removal strength and cannot replace observation of the borehole bottom section and interface condition; when When doing so, the sample's drying condition, weighing system, and surface contamination should be checked first. The results should not be used for release decisions until the cause is confirmed. The effective treatment area is greater than 0.

[0040] like Figure 2 As shown, in this main embodiment, the production board 100 and the witness sheet group 110 of the same batch use the same halogen-free laminated medium batch and correspond to the same target laminated layer level. The witness sheet group 110 of the same batch includes a through-hole parallel sub-sheet 111, a drill-de-smudge parallel sub-sheet 112, and a metallized through-hole filling parallel sub-sheet 113, and may include a reference retention sub-sheet 114; the final reliability evaluation uses a reliability sample with a corresponding interconnect structure. Each sub-sheet can be located in different board edge areas of the same panel; when the panel space is insufficient, independent accompanying test boards within the same lamination load can also be used. By simultaneously binding the production board 100 and the three parallel sub-sheets to the material batch, laminated layer level, and lamination load, the gating results can be directed to a specific set of production boards, rather than unconditionally extrapolating the results of a certain general test sheet to other batches or other layers.

[0041] Combination Figure 2 It can be seen that the parallel sub-plate 111 for hole forming completes the hole forming gate control. After the required destructive cross-section testing, the sample is sealed; the drill-decontaminated parallel sub-segment 112 is independently pressed... Hole formation and candidate desmearing treatment; metallized filler parallel sub-plates 113 independently... Hole forming, pressing After descaling, metallization and hole filling are performed. The seed layer section is used as... During the evaluation, the metallized via-filling parallel sub-section 113 is further divided into physically separable metallized verification sub-region 113a and via-filling verification sub-region 113b. The former is sliced ​​and sealed, while the latter is processed according to the criteria. The seed layer is reformed before filling the wells. This arrangement ensures that each gating stage is established on a specimen that has not been altered by the previous destructive test, thus preserving both upstream cross-sectional evidence and the true downstream preceding state.

[0042] like Figure 3 As shown, both the production board 100 and the witness chip group 110 in the same batch include a core board or previous stacked layer 120, a halogen-free stacked dielectric layer 130 disposed on its outer side, and an outer copper layer 140 at the target stacked layer position; the core board or previous stacked layer 120 has a capture pad 150 corresponding to the target micro-blind via 160. After the via material and the halogen-free stacked dielectric layer 130 of the outer copper layer 140 are removed by laser, the capture pad 150 is exposed at the bottom of the micro-blind via 160. Subsequently, a seed layer 171 is formed on the via wall and the via bottom, and the micro-blind via 160 is filled with filler copper 172 to form a conductive interconnect between the outer copper layer 140 and the capture pad 150.

[0043] Combination Figure 3 It is understood that this embodiment can be used for one or more rounds of sequential lamination. The medium can be a halogen-free prepreg, resin-coated copper foil, or laminated film; the micro-blind via 160 can be a single-layer blind via, or it can be formed as a staggered or stacked via after layer-by-layer verification. When using alternative media or via types, the original window is not directly inherited, but the material batch and target lamination level are re-established according to this embodiment. , and This avoids mismatches in pore shape and interface window due to differences in medium moisture absorption, filler or curing shrinkage.

[0044] like Figure 1 and Figure 2 As shown, in step S101, the core board or previous layer 120, halogen-free dielectric layer 130, and outer copper layer 140 used for the current layer are first obtained, and the corresponding material batch number, incoming material status, storage, and baking records are read. The determination of halogen-free is limited to the actual material being evaluated; if the project requires the entire board diameter, the corresponding records of solder resist, character materials, and other retained materials are saved separately, instead of using a single substrate report to replace the evaluation of the entire board composition.

[0045] Combination Figure 2It is understood that step S101 establishes an association including at least the material batch, target lamination level, lamination load, witness sheet group 110 identifier, and three parallel sub-sheet identifiers, and maps this association to the production board 100. If a process control terminal 600 is used, the association module 651 writes the above identifiers into the same batch record; if a paper work order is used, the operator checks and signs the identifiers of the production board 100, the witness sheet group 110, and the laminated materials before lamination. If the association is not completed or the identifiers conflict, the production board 100 does not enter the lamination unit 200, thus avoiding the use of witness results from other material batches for the current production board from the process flow path.

[0046] Alternatively, instead of using a fixed field combination, QR codes, barcodes, controlled batch numbers, or unique paper serial numbers can be used to achieve the same mapping. The change in record format does not affect the core relationship, as long as any gating result can point back to the corresponding production board 100, material batch, and stacking level, and can identify the pre-processing status of each of the three parallel sub-pieces.

[0047] like Figure 2 and Figure 3 As shown, in step S102, the halogen-free laminated dielectric layer 130 and the outer copper layer 140 are stacked on the target surface of the core board or the previous laminated layer 120, and the lamination unit 200 laminates the production board 100 and the witness sheet group 110 of the same batch under the same lamination load. The lamination unit 200 records the heating, pressurizing, heat preservation and cooling processes; after lamination, the thickness of the cured dielectric, the board surface condition and the alignment condition are measured. By placing the production board 100 and the witness sheet group 110 of the same batch in the same load, the representativeness of the witness sheet for the flow, curing and thickness of the dielectric in this round is enhanced.

[0048] Combination Figure 3 To illustrate the establishment of the candidate window, in the first round of engineering verification, the thickness of the curing medium can be ranged from 50 μm to 80 μm, and the peak temperature from 170 ℃ to 195 ℃, the pressure from 1.5 MPa to 3.5 MPa, and the effective core insulation time from 45 minutes to 90 minutes can be used as the candidate observation range. The above values ​​are used to cover possible material and load responses and are not fixed production formulations for a particular material; the actual center values ​​should be within the allowable range of the material's technical data and determined by the post-lamination thickness and interface state.

[0049] like Figure 2As shown, when witness panel 110 in the same batch cannot be laminated under the same load as production board 100, it can be treated as an independent accompanying test board. In this case, the acceptable peak temperature difference, effective heat preservation time difference, heating and cooling process, and board position category should be pre-defined, and equivalence should be verified by the cured thickness or other measurable conditions. If the equivalence fields exceed the controlled boundaries, the witness panel 110 in the same batch will not be used to release production board 100, but will be re-prepared to accompany it, thereby avoiding the substitution of similar actual thermal history for similar scheduling.

[0050] Combination Figure 1 It is known that if thickness exceeds limits, obvious misalignment, delamination, or missing records occur after lamination, the process control terminal 600 will output a lockout state, or the controlled paper process card will stop flowing to step S103; the production board 100 and the witness sheet group 110 of the same batch will remain isolated. The recovery condition is that the lamination record is complete and the newly made or retained representative sample passes the verification. This action limits material or lamination abnormalities to before hole formation, avoiding subsequent hole shape differences from being misjudged as changes in the working status of the laser hole forming equipment 300.

[0051] like Figure 4 As shown, in step S103, the laser drilling device 300 reads the data around the reference formula. Candidate combinations are set, and multiple micro-blind holes 160 are formed on the parallel sub-wafer 111. Candidate factors may include effective energy, pulse number, number of scans, laser focus position, windowing method of the outer copper layer 140, and board surface position. For example, the following can be set: , and These three relative energy levels, and... , and These three pulse count levels are combined to obtain nine candidate regions. In the formula, This represents the normalized effective energy reference value corresponding to the baseline formulation, which can be used for relative comparisons. Normalized to 1, therefore and All are dimensionless relative levels; This represents the reference pulse number, a positive integer, in pulses. The candidate pulse number should fall within the valid range allowed by the laser aperture drilling equipment (300). If the number of pulses is below the minimum allowable number by the equipment, the invalid combination should be discarded or the adjacent valid number of pulses within the allowable range of the equipment should be used. This relative level setting is used to find a continuous range of acceptable parameters around an existing benchmark recipe and does not require specific equipment models or undisclosed absolute power values.

[0052] Combination Figure 3 and Figure 4 , The detection unit 310 measures the top diameter of the micro blind hole 160. Bottom diameter Hole depth and hole offset And observe whether the bottom of the hole is sufficiently exposed for the capture pad 150, and whether the capture pad 150 has erosion or thermal effects exceeding the criteria. As a candidate verification entry point, the top diameter can be... Coverage from 75 μm to 125 μm, bottom diameter Coverage ranges from 50 μm to 90 μm, with pore depths ranging from 50 μm to 80 μm, and priority is given to investigating these areas. The hole shape category. The above geometric range is used to illustrate the measurement and grading method; the actual hole shape given in the product drawing may be narrower or different.

[0053] refer to Figure 4 The center and edge sampling positions can be pre-fixed in each candidate region, and the same number of holes can be used at each position. Top diameter Bottom diameter Hole depth and deviation According to Figure 3 The cross-section or three-dimensional measurement reference is shown; the grading criterion is that the bottom of the hole is open to capture the continuous visibility of the pad 150 within the predetermined bottom observation area; pad damage is compared with at least one of the following: remaining copper thickness, erosion depth, or affected area, to a pre-fixed limit. If any inspected hole exceeds the limit for a single product sample, the candidate combination is not considered passed; only when adjacent combinations meet the same sampling and limit are they included in the continuous qualified parameter area. This rule implements the criteria of sufficient exposure and exceedance into storable images, geometric measurements, and grading records.

[0054] like Figure 4 As shown, The detection unit 310 does not use the openness of the hole as the sole criterion, but simultaneously compares the hole shape, the openness of the hole bottom, the offset, and the pad damage. Only when multiple adjacent candidate combinations pass at different board positions is the common area defined. This joint criterion avoids selecting combinations with excessively low energy but accidental activation, as well as combinations with excessively high energy and seemingly regular aperture shapes but where the capture pad 150 has been eroded.

[0055] Combination Figure 4 ,like If the test fails, production board 100 remains in the pre-hole drilling state, and the hole-drilling parallel sub-piece 111 is sealed and the corresponding combination is recorded. First, the thickness of the curing medium, the laser focus position, the copper surface condition, the positioning target position, and the laser path are checked. Then, the candidate factors are adjusted using a new hole-drilling parallel sub-piece 111 and the test is repeated. The failure period is not compensated by extending the desmearing time, because desmearing cannot restore the eroded capture pad 150, and will also mix the two types of anomalies, namely, unopened hole bottom and thin layer residue at the hole bottom, in the same interface.

[0056] refer to Figure 4 In one alternative embodiment, the laser aperture forming apparatus 300 can employ a combined energy path that acts on the outer copper layer 140 and the halogen-free deposited dielectric layer 130 respectively, or it can employ a path that first forms a copper window and then removes the dielectric; as long as the aperture is still formed on the current batch and the current level of the parallel sub-pieces 111. , and by Simultaneous verification of open and damaged boundaries falls under the same implementation logic. For indicators that can be covered by non-destructive testing, optical or three-dimensional measurements can be performed first, followed by sampling sections of parallel holes; the already sliced ​​parallel sub-pieces 111 are no longer used for interface gating. Verification.

[0057] like Figure 5 As shown, in step S104, an undamaged de-drilling parallel sub-plate 112 is selected, and it is first pressed... Micro-blind holes 160 are formed, and then candidate desmearing conditions are applied by the desmearing unit 400. The desmearing unit 400 can be a wet processing line, a plasma processing device, or a combination of both. Candidate factors can include processing route, time, temperature, solution state, plasma processing energy, and processing sequence; to compare processing intensity, three or more adjacent processing levels from weak to strong can be set according to a preset step size, instead of simply comparing the two endpoints of processed and untreated.

[0058] Combination Figure 5 , The detection unit 410 can detect within a predefined shielded area and effective processing area. The quality of the parallel sub-plate 112 before drilling decontamination treatment. and post-processing quality Measurement.

[0059] The same drying temperature, drying time, environmental equilibrium conditions, weighing equipment, and weighing resolution should be used before and after the treatment, and the change in mass per unit area should be calculated according to the following formula:

[0060] In the formula, . , and Using the same unit of mass, Using area units, The unit of measurement is mass divided by area. This indicator only represents the overall material removal intensity; therefore, the following should also be observed: thin layer residue at the bottom of the hole, resin shrinkage, glass fiber protrusion or erosion, damage to the halogen-free deposited dielectric layer 130, and the surface condition of the captured pads 150. Only when both the change in mass per unit area and the interface observation results are within the continuously acceptable parameter range of the preset criteria is the de-drilling window determined. .

[0061] refer to Figure 5 , Can be used and Corresponding center and edge sampling locations were used, and applicable limits were fixed before testing for the percentage of residual area at the bottom of the hole, resin retraction depth, glass fiber protrusion length, dielectric damage depth, and remaining copper thickness of the pads. Residual area at the bottom of the hole was measured cross-section or using a validated imaging method. Retraction and protrusion were read along the hole wall normal, and the pad condition was compared with an untreated reference area on the same wafer. If any indicator exceeded its single-sample limit, the candidate combination containing that hole was not considered passed. Quality variations were only used as circumstantial evidence of processing intensity and not considered significant. Cover any interface damage item.

[0062] like Figure 5 As shown, to illustrate candidate coverage methods for wet processes, 70°C to 85°C and 5 to 20 minutes can be used as the initial comparison boundary, with adjacent levels set based on actual chemical activity. This range does not represent the applicability of all halogen-free materials; material chemical resistance, filler exposure, and the surface condition of the trapped pad 150 determine whether the candidate area shrinks or an alternative route is used. By simultaneously incorporating bottom hole cleaning and media damage... This can avoid only pursuing larger sizes This can cause excessive resin shrinkage or fiberglass protrusion.

[0063] Combination Figure 5 ,like If the process fails, the process control terminal 600 will lock the metallization and via filling unit 500, or a controlled paper process card will isolate the production board 100 before de-drilling. If the issue manifests as residue at the bottom of the via with minimal media damage, the activity of the chemical solution, plasma treatment status, treatment time, and water rinsing should be reviewed. If the issue manifests as shrinkage, glass fiber protrusion, or pad erosion, the treatment should be reduced or a compatible route should be used. If the review reveals that the bottom of the via was originally not open, a follow-up investigation should be conducted. The process was repeated on the new drilling parallel sub-section 111 and the new descaling parallel sub-section 112, respectively. , This exception cannot be classified as Further escalation of treatment was then implemented. (Reference) Figure 5In one alternative approach, a material-compatible plasma pretreatment can be performed first, followed by a milder wet treatment; alternatively, plasma treatment or wet treatment alone can be used. When using halogenated process gases, their suitability and residues should be verified according to the evaluated object and customer specifications. The fact that the final board is labeled as halogen-free does not automatically mean that any processing gas can be used. Regardless of the chosen approach... The release will still be based on the combined results of bottom hole cleaning and interface damage.

[0064] like Figure 6 As shown, in step S105, an undamaged metallized through-hole parallel sub-plate 113 is selected and first pressed... Hole forming, pressing After removing drilling debris, the material enters the metallization and via filling unit 500. When cross-sectional verification of the seed layer is required, the metallization and via filling parallel sub-plate 113 is pre-configured with physically separable metallization verification sub-region 113a and via filling verification sub-region 113b; both sub-regions have the same and Accumulate preceding conditions. For wet metallization routes, controlled micro-etching can be performed first to expose fresh and uniform capture pad 150 copper surfaces. After rinsing with water, keep the board wet and proceed with conditioning, pre-dip, activation, and chemical copper plating. Avoid prolonged drying after micro-etching to reduce the chance of copper surface re-oxidation and contamination introduced into the holes.

[0065] Combination Figure 6 After chemical copper plating, first by The detection unit 510 checks whether the seed layer 171 in the metallization verification sub-region 113a continuously covers the hole wall and the bottom of the hole, and defines the controlled condition that meets the precondition as the metallization sub-window. If a cross-sectional inspection is used, the metallization verification sub-region 113a is sealed after inspection; subsequently, the already passed inspection is performed on the still intact through-hole verification sub-region 113b. The seed layer 171 is reformed before proceeding to flash plating or low-current pre-coverage and main fill. To illustrate candidate coverage methods, the chemical copper plating thickness can be examined from approximately 0.3 μm to 0.8 μm, and the flash plating thickness from approximately 1 μm to 3 μm; these values ​​are used to construct seed layer state grading and are not verified results. If the seed layer 171 is discontinuous, the via filling verification sub-region 113b will not proceed to main fill; activation, surface chemistry, bath state, and waiting time will be reviewed first. If a non-destructive testing method that has been verified not to alter the seed layer is used, the inspected and intact sub-region can continue, but its identity and inspection receipt will still be retained.

[0066] like Figure 3 and Figure 6 As shown, it can be based on , The micro-blind vias 160 are classified into multiple via shapes and seed layer state categories based on the board surface pattern density, the continuity of the seed layer 171, and the seed layer thickness. Board surface pattern density refers to the proportion of the copper pattern area within a predetermined board surface area to the total area of ​​that area. In the formula, , and All use the same unit of length. and All values ​​are dimensionless. For a single candidate category, current density is expressed in amperes per square decimeter (A / dm²); for example, a low-current pre-coverage segment of 0.5 A / dm² to 1.0 A / dm², lasting 5 to 15 minutes, can be used initially, followed by a main fill segment of 1.2 A / dm² to 2.0 A / dm², lasting 40 to 80 minutes; DC, pulsed, or pulsed inverse waveforms are all acceptable candidate waveforms. The current and time ranges mentioned above are only for demonstrating how to establish... The actual conditions are determined by the tank liquid capacity, orifice type, and cross-sectional results.

[0067] Combination Figure 6 , The detection unit 510 performs cross-sectional or applicable non-destructive testing on the predetermined center and edge holes of the via filling verification sub-region 113b, comparing the continuity of the seed layer 171, voids and seams within the via filling copper 172, via opening depressions, via bottom interface separation, copper thickness, and resistance; and defines the controlled conditions that meet the via filling criteria as the via filling sub-window. Seed layer continuity can be graded based on continuous coverage of the entire circumference of the hole wall and the hole depth direction; voids, seams, and interface separation are recorded according to their presence, maximum size, or proportion of cross-sectional area; depressions are read by the vertical distance from the reference copper surface at the hole opening to the lowest point of the 172 copper filling; copper thickness and resistance are compared according to the units and limits in the procurement documents or applicable inspection specifications.

[0068] The number of holes, cross-sectional orientation, and plate distribution for a given candidate combination are fixed before the test. If any tested hole exceeds the preset limit for a single sample, the combination is not recorded as passed. Only... Preconditions and Locking is only enabled when all hole-filling criteria are met. This sequence can distinguish between two types of abnormalities: discontinuous seed layer leading to subsequent plating defects and continuous seed layer but mismatched main fill waveform, thus avoiding confusion between the two as a single plating defect.

[0069] like Figure 6 As shown, if the seed layer 171 is continuous but voids, seams, or excessive depressions appear in the via-filling copper 172, the additive status, temperature, flow, and current waveform can be checked, and the pre-covering section or main filling section can be adjusted on the new metallized via-filling parallel sub-plate 113 before re-execution. If there are still residues at the bottom of the hole or the captured pad 150 is damaged, then return to the dependency relationship. or The corresponding gating and all downstream gating are re-executed. When seed layer 171 is discontinuous, compensation is not achieved by increasing the main fill current because a higher current cannot restore a continuous conductive initiation layer at the insulation break.

[0070] refer to Figure 6 In one alternative embodiment, a direct metallization route validated by current materials and aperture shapes can be used instead of activation plus chemical copper plating, with the continuity of the direct metallization layer as the basis for... Preliminary criteria. Regardless of whether chemical copper plating or direct metallization is used, All remain Prior to The dependency order is as follows: hole filling is allowed only after the metallization pre-state is passed, and the hole filling result cannot cover up the metallization discontinuity in reverse.

[0071] like Figure 1 , Figure 6 and Figure 10 As shown, production board 100 is released in stages: Accepted only after passing. The drilling conditions in the process, after drilling is completed, are isolated before removing drilling debris; Accepted only after passing. The descaling conditions in the process are completed, and the equipment is isolated before metallization. Accepted only after passing. The metallization and via filling conditions in the process. This sequence does not merge three windows into a single set of parameters detached from the preceding state; instead, it associates each window with its gating evidence, material batch, target layer level, equipment or slot line, and effective time. Thus, the same... Only used for its predecessor The formed hole, the same Only used for corresponding and The interface formed; if any stage is not passed, the production board stops in a state where it has not yet received the corresponding downstream processing.

[0072] Combination Figure 7 When the process control terminal 600 is used, the associated module 651 reads the material batch-target layer level identifier of the production board 100, and the gate control module 652 checks. , , The release and traceability module 653 outputs the controlled parameter version and release status to the corresponding process unit only after the status is confirmed. Each process unit returns a receipt upon completion, including equipment, channel line, start time, end time, completion status, and parameter version; if a receipt is missing, the next unit remains locked. When using controlled paper process cards, another independent reviewer can verify the same fields, and physical isolation racks or controlled flow markers can be used to prevent unreleased panels from entering the next process.

[0073] like Figure 6 As shown, production board 100, in principle, does not use destructive cross-sections as the online gate object for each board; destructive testing is undertaken by associated parallel sub-pieces, board edge units, or reliability test specimens. Production board 100 is subject to applicable non-destructive testing and final sampling inspection. This maintains product integrity while ensuring that gate evidence comes from test specimens with corresponding preceding states to the product.

[0074] like Figure 8 As shown, when the production board 100 has a next target lamination layer, S101 is first re-executed for that layer to establish the association between the new material batch, target lamination layer, and witness sheet group 110 in the same batch; then S102 is executed to ensure that the new witness sheet group 110 in the same batch is under the same lamination load or verified equivalent thermal history as the production board of that layer, and the curing medium thickness, copper surface condition, and available cumulative thermal history fields are re-measured. Even if the subsequent layer uses the same material name as the previous layer, the previous layer's material name is not copied by default. , and Instead, it continues to execute S103 to S106, and completes the process again. , , And phased production release, and form dedicated controlled parameters for this layer.

[0075] Combination Figure 8 It has two lamination layers on each side and a core board in the middle. Each conductive layer In multi-stage layered structures, This indicates the number of conductive layers contained in the core board, and The value is a positive integer. The first and second stacked layers retain their respective through-hole parallel sub-sheets 111, de-drilling parallel sub-sheets 112, and metallized through-hole filling parallel sub-sheets 113. Later-formed stacked layers undergo more preceding thermal cycles, and their curing medium thickness and copper surface condition may differ; layer-by-layer re-verification ensures that this difference is measured and incorporated into the process window before the production board 100 enters the through-hole process, rather than being traced back after a final thermal reliability anomaly. Layer-by-layer through-hole bottom or through-hole filling checks are not themselves a distinguishing feature of this assembly; this embodiment emphasizes that each target stacked layer level is reconfigured with physically independent parallel sub-sheets according to the through-hole window that layer has already passed. Remove the dirt from the window. and metallized sub-window Reconstruct the accumulated preceding state and pass on the changes in the upstream process window step by step to the downstream evidence of stopping use and the production board 100 isolation action.

[0076] refer to Figure 8 If historical data proves that a certain change only affects Without affecting and A reduced verification path can be adopted; however, the reduced path must be supported by established equivalence boundaries and historical evidence. Without such evidence, changes in material batches, lamination levels, critical equipment, or bath solutions will trigger a full verification process by default. to Re-verify.

[0077] like Figure 1 and Figure 8 As shown, after all target layers are completed, the production board 100 undergoes circuit connectivity, electrical performance, and appearance inspections. The associated board edge units, resistance monitoring samples with genuine micro-blind via interconnects, or other parallel reliability samples are subjected to resistance monitoring and cross-sectional inspection before and after thermal cycling. The resistance monitoring samples can be Type D reliability samples, whose stack-up structure, micro-blind via structure, and conductive paths should correspond to the structure of the production board being evaluated. Different parallel samples are used for the cross-sections before and after thermal cycling to avoid repeatedly using the same cut sample as a post-thermal-cycle sample. Specific thermal cycling conditions, measurement methods, and release thresholds are determined based on the product procurement documents and applicable inspection specifications and are fixed before testing.

[0078] Combination Figure 8 Final inspection anomalies do not directly result in a single liability conclusion based on the final appearance. The process control terminal 600 or the controlled paper process card links the anomaly to... , , The original evidence is related to: the hole bottom not being open or pad erosion triggering the connection. Verification; bottom hole residue, resin shrinkage, or glass fiber protrusion are the primary triggers. Verification; discontinuous, void, seam, or depression in the seed layer will trigger priority. Verification; abnormal resistance after interlayer separation or thermal cycling can simultaneously trigger verification of the material, lamination, and multiple micropore interface stages. Only after retesting or confirmation with a control sample should the corresponding window be adjusted or the relevant batches isolated.

[0079] like Figure 2As shown, in the first parallel embodiment, the witness sheet group 110 of the same batch is located on the edge of the same production panel as the production board 100 and is physically divided into a hole-forming parallel sub-sheet 111, a drill-deburring parallel sub-sheet 112, a metallized through-hole filling parallel sub-sheet 113, and an optional reference retention sub-sheet 114. The four sub-sheets use the same batch of halogen-free laminated dielectric layer 130 and outer copper layer 140 as the production board 100, and are laminated together with the production board 100 within the lamination unit 200. The reference retention sub-sheet 114 retains its initial state after lamination and is used to verify the thickness of the cured dielectric, the copper surface, or the lamination state in case of measurement discrepancies.

[0080] Combination Figure 2 and Figure 9 The sub-pieces on the edge of the plate can be distinguished from each other by cutting grooves, separable connecting bridges or reserved partition lines, so that the other sub-pieces are not damaged when a certain sub-piece is sliced. After passing, the intact de-drilling parallel sub-plate 112 remains intact. to form a hole; After passing through, the metallized through-hole parallel sub-plate 113 remains intact. Drill holes and press De-drilling. This physical partition prevents the destructive test sample from flowing onto the separable sample and allows the downstream sub-slab to reconstruct the accumulated preceding state through the upstream window.

[0081] refer to Figure 2 When there is insufficient space at the edge of the panel, multiple hole arrays with independent boundaries can be set on the same separable carrier, and the corresponding arrays can be physically separated into sub-pieces by cutting grooves or predetermined dividing lines at the detection front edge. The area is sealed after cutting, embedding, or grinding and is no longer used for interface gating. Verification or Used for and The areas remain intact before they are activated, and cutting or sample preparation operations must not enter their reserved boundaries. The same rule applies to the metallization verification sub-area 113a and the well-filling verification sub-area 113b. This replacement maintains the physical independence of parallel specimens while allowing for adjustments to the geometry based on panel allowances.

[0082] like Figure 1 and Figure 2 As shown, in the second parallel embodiment, the witness panel 110 is not located on the same panel as the production board 100, but is set up as an independent accompanying test board. The accompanying test board uses the same critical medium and copper surface material batch as the production board 100, is under the same load or verified equivalent thermal history category of the lamination unit 200, and records the corresponding equipment or slot line and controlled waiting time range during the laser, descaling, metallization and via filling stages.

[0083] Combination Figure 1 The production board 100 adopts a staged release method. After lamination, the production board 100 is initially kept isolated before hole forming until the parallel sub-sheet 111 with hole forming is completed. ; After passing, production board 100 is pressed. Hole formation is performed and the hole remains isolated before entering the desmearing unit 400 until the desmearing parallel sub-plate 112 is completed. ; After passing, production board 100 is pressed. Remove drilling debris and keep it isolated before entering the metallization and via filling unit 500 until the metallization and via filling parallel sub-plate 113 is completed. ; After passing, production board 100 is pressed. Metallization and via filling are completed. Therefore, gating is not a post-production inspection after the finished product is completed, but directly determines whether the production board accepts the next physical processing.

[0084] refer to Figure 1 When the production cycle is not suitable for all production boards to wait at each station, a preliminary verification board and its corresponding witness board group 110 from the same material batch and target stacking level can be selected first. The remaining production boards remain in an isolated state that does not change the critical interface. After the preliminary verification is completed, the associated production boards are released. The technical boundary of this path is still: the witness result must represent the released production board, and boards that have already entered the downstream and changed their interfaces cannot be used as boards waiting for gating.

[0085] like Figure 1 , Figure 2 and Figure 8 As shown, in the third parallel embodiment, the same material batch and target lamination level can be further divided into multiple controlled production subgroups according to lamination load, board surface location category, equipment effective time range, or bath solution effective usage time range, and each production subgroup is configured with its own batch witness sheet group 110. Each batch witness sheet group 110 includes physically independent hole-forming parallel sub-sheets 111, drill-de-stain parallel sub-sheets 112, and metallization-filling parallel sub-sheets 113, and cannot be composed of a single subgroup. or The result replaces another subgroup that exceeds the equivalent boundary.

[0086] Combination Figure 1 When the tempo allows, multiple sets of testimonial videos can be played in a rolling sequence: the first set enters... During verification, Group 2 can perform the procedure while maintaining isolation before the production board is drilled. Group 1 enters During verification, the second group can... After passing through, the corresponding production board is released for hole drilling. Scrolling only changes the time arrangement, not the strong dependency order within a single group; any group still needs to be... Release through the hole, by Release to drill for dirt, by Metallization and via filling are allowed, and damaged sub-chips or sub-regions are not allowed to flow backward.

[0087] refer to Figure 8 When a certain group Change or If the verification fails, only stop using the dependency. Formed , and corresponding , Evidence is collected and isolated for mapping to the production board of that group; other groups may proceed only if their material batches, target layer levels, lamination loads, equipment effective time ranges, and bath conditions still fall within the verified equivalent boundaries. The same applies when changing this group. Evidence is no longer used for release. For more than two stacked levels, S101 and S102 are re-executed at each level and a new batch of witness pieces 110 is configured. The layer-by-layer inspection itself is not the difference in this parallel route. The difference is that the rolling schedule still maintains the cumulative prior reconstruction, the step-by-step transmission of dependency failures, and the phased release of production boards.

[0088] In embodiments without a process control terminal 600, the same process release constraints as those in electronic control paths can be executed via controlled paper process cards, independent verification, and physical isolation. The controlled paper process card records at least the production board 100 identifier, material batch, target stacking layer level, identifier of the same batch of witness sheet group 110, and the identifiers of the hole-forming parallel sub-sheet 111, the drill-smudge removal parallel sub-sheet 112, and the metallization filling parallel sub-sheet 113, as well as the hole-forming window. Remove the dirt from the window. Metallization and hole filling windows Version, hole-forming gate control Interface gating and metallized through-gating The status, corresponding equipment or line, start time, end time, completion status, operator, and another independent reviewer are required. If any of the above fields are missing, conflicting, or not fully reviewed and signed off, the production board 100 remains in an isolated state prior to the corresponding downstream process.

[0089] Physical isolation can be achieved through independent isolation racks, sealed bags, controlled flow tags, or equipment operation permissions. Its function is to prevent production boards 100 that have not obtained release status from entering the next physical process. After each gate is passed, the operator and another independent reviewer verify the identity of the parallel sub-wafer, the previous process window version, and the test results before releasing the physical isolation of the corresponding stage. This embodiment only changes the recording and transmission method of release status, without changing the physical processing of lamination, laser drilling, desmearing, metallization, and via filling, nor does it change the dependency relationship between the three parallel sub-wafers in rebuilding the accumulated previous status.

[0090] like Figure 7 and Figure 8 As shown, the following abnormal handling uses process control terminal 600 to illustrate the automation path, but process control terminal 600 is not a necessary device for the manufacturing method. When process control terminal 600 is not set up, authorized personnel perform the same identity verification, criterion comparison, process window dependency failure marking, and review signing on controlled paper process cards, and use isolation racks, sealing bags, equipment permissions, or controlled flow identifiers to achieve the same physical locking and unlocking conditions; therefore, the output locking state referred to in this chapter also includes the aforementioned manual record control and physical isolation actions.

[0091] like Figure 7 and Figure 8 As shown, when Detection unit 310 Detection unit 410 or If the detection unit 510 does not output complete measurement results, the cross-sectional image cannot be mapped to the sub-piece identifier, or the two measurement methods give contradictory results, the interface 640 does not submit a pass status to the gate module 652, and the release and traceability module 653 keeps the corresponding downstream process locked. The production board 100 and the parallel sub-pieces that have not yet undergone destructive testing are physically isolated, and the pass status is not presumed based on missing data.

[0092] Combination Figure 8 During recovery, the sample identification, sample preparation location, measurement equipment status, and repeatability are first verified. Reference retention sub-segment 114, the retained sample, or a new parallel sub-segment corresponding to the affected gate can be used, and another applicable measurement method is employed for verification. Only after the measurement source, sample identity, and result consistency are all restored will the corresponding gate be re-executed. This process first eliminates sample preparation or measurement system anomalies to avoid incorrectly adjusting production parameters when measurement distortion occurs.

[0093] like Figure 7As shown, when interface 640 does not receive completion receipts from lamination unit 200, laser drilling equipment 300, de-drilling unit 400, or metallization and filling unit 500 within the preset process cycle, or when the control connection between process control terminal 600 and process unit is interrupted, processor 610 sets the current batch status to incomplete, and gate module 652 does not allow the subsequent process to start. The preset receipt time limit is set according to the normal processing cycle and safety shutdown procedure of the corresponding equipment, and does not use an arbitrary fixed duration unrelated to the process.

[0094] Combination Figure 8 When an emergency shutdown occurs during a dry process, the workpiece remains in a defined safe position and retains its batch identification. If it occurs during a wet continuous process, follow the validated moisturizing, transfer, or removal procedures for that tank line to prevent the internal interfaces from being exposed to dryness at an unknown time. Before resuming operation, verify the equipment status, actual processing stage, tank solution or laser formulation, and workpiece interfaces. If the previous status cannot be confirmed, isolate the associated production board 100 and re-execute the affected gating using a new corresponding parallel sub-board, instead of directly resuming operation after equipment reset.

[0095] like Figure 7 As shown, the association module 651 reads the material batch and target layer level of the production board 100, and the gating module 652 compares the version of the formula to be executed with the controlled version that has passed the gating. When the formula on the equipment side exceeds... , or When the boundary, or the material batch—target layer level identifier—is inconsistent with the formula version, interface 640 outputs a lock signal and retains the mismatched formula version, equipment identifier, and board identifier. After locking, instead of manually modifying a parameter to bypass the comparison, the applicable process window and its version are re-verified. When a duplicate start request is received in the same batch, processor 610 checks the completion receipt of the current step; if the step has been completed, the second start is blocked to prevent the micro-blind via 160 from being subjected to repeated laser, repeated de-drilling, or repeated electroplating. If the equipment power failure and restart cause inconsistencies in the status, the actual processing status is determined based on the physical location of the board, the equipment log, the slot line record, and the status of the witness sheet group 110 and its parallel sub-sheets in the same batch; if it cannot be confirmed, it is treated as an affected window failure.

[0096] like Figure 4 and Figure 8 As shown, when used as a hole gate The test results indicate that when the bottom of the hole is not fully exposed, the hole position is offset beyond the criterion, the capture pad is thinned by 150mm, or there is thermal damage, It is in a state where it cannot be released. and No available preceding inputs. Production board 100 maintains pre-via drilling isolation; if the production board has already been drilled according to the original via window... If a hole is formed, the batch will be isolated and handled independently, and will not be directly subjected to further drilling to remove contaminants.

[0097] Combination Figure 4 The verification process includes comparing the thickness of the curing medium, the condition of the copper surface, the focal point, the energy path, the pulse combination, and the location of the target; adjusting the candidate hole-forming factors based on the verification results, and re-performing the process on the new parallel hole-forming sub-chip 111. New hole-forming window After formation, the process is repeated using a new descaling parallel sub-blade 112 and a new metallized filling parallel sub-blade 113. , By making the old hole window dependent. De-drilling window Metallization and hole filling windows Stopping the use of the release function can prevent the incorrect use of the original downstream process window after the orifice shape has been changed.

[0098] like Figure 5 and Figure 8 As shown, when Through the interface gate The test results indicate that there is still residue at the bottom of the hole, excessive resin shrinkage, protruding glass fibers, or damage to the surface of the trap pad 150. It can be retained if its applicable conditions remain unchanged. and Stop for release. Production board 100 remains before desmearing, or for desmearing windows that have not passed verification. The processed panels are isolated.

[0099] Combination Figure 5 The activity of the chemical solution, temperature, treatment time, plasma treatment status, water washing and drying conditions were verified, and the process was repeated on the new descaling parallel sub-plate 112. ; After passing, press on the new metallized through-hole parallel sub-plate 113 and new descaling window Rebuild the preceding state and re-execute Residue at the bottom of the hole cannot be directly addressed by increasing the thickness of the chemical copper plating layer or extending the filling time. Shrinkage and glass fiber damage cannot be covered by thickening the copper layer.

[0100] like Figure 6 and Figure 8 As shown, when seed layer 171 is discontinuous, first review the controlled micro-etching, wetting state, activation, chemical copper plating, or direct metallization stages, and if necessary, revisit the interface gating. The corresponding bottom interface of the hole; the main filling current is not increased. When the seed layer 171 is continuous but the copper filling layer 172 has voids, seams, or depressions, the state of the bath solution, flow, hole shape classification, and pre-coverage and main filling waveforms should be checked first; only when the re-examination shows that the previous evidence is invalid should we return to or .

[0101] Combination Figure 8 When the batch of halogen-free deposition medium, supplier, copper surface material or surface condition, laser drilling equipment 300, descaling tank line, metallization tank line, or key bath solution batch changes, the original controlled parameters are not automatically inherited. If there is no historical equivalence evidence, complete hole gating should be used. To metallized through-gating Re-verify; if a verifiable influence boundary already exists, it can be done according to... , , Local verification is performed on the dependencies.

[0102] refer to Figure 8 When an abnormality is detected in the resistance monitoring after final inspection or thermal cycling, production board 100 and related samples are isolated. Interlayer separation, abnormal hole bottom interface, or resistance changes may simultaneously involve materials, lamination, hole forming, descaling, and metallization. The sole responsibility is not determined directly by the final morphology. After confirmation using parallel sample cross-sections, retained sample retesting, or single-variable comparison, a decision is made on which window to rebuild, which batch to isolate, or which process equipment route to stop.

[0103] like Figure 7 As shown, the optional process control device is executed by the process control terminal 600 and includes an association module 651, a gate control module 652, and a release and traceability module 653. The association module 651 can be implemented by database record logic, controlled form logic, or memory objects. Its inputs are the production board 100, the same batch of witness sheet group 110, the material batch, and the target stacking layer level identifier. Its output is an association record that can map the detection results of the three parallel sub-sheets to the production board 100.

[0104] Combination Figure 7 The gating module 652 can be implemented using comparison rules, state transition logic, and a dependency table. Its input is... Detection unit 310 Detection unit 410 and The detection unit 510 outputs measurement results and applicable criteria; its actions are to check the completeness of the results, sample identity, previous process window version and criterion status item by item; its output is pass, fail or need to be reviewed. Change makes , Failure Change makes The failure rules are also executed by the gating module 652, but the result of the rules must be implemented to re-prepare and process the isolation of the new corresponding parallel sub-chips and production board 100, and cannot just change the screen display.

[0105] like Figure 7 As shown, the release and traceability module 653 receives the status from the gating module 652, and only outputs the controlled process parameters and their versions allowed for the next process after the corresponding gating is passed. It also saves the equipment, channel line, start time, end time, completion status, and parameter version returned by the process unit. If the receipt is missing, the sample identification is inconsistent, or the parameter is out of bounds, the release and traceability module 653 outputs a lock status and sends the exception back to the gating module 652 to determine the relevant process stage that needs to be reviewed.

[0106] Combination Figure 1 and Figure 7 The control functions can be further gradually mapped to S101 to S108.

[0107] S101 is executed by the material batch-target lamination level association function in the association module 651. Its inputs are the material batch identifier, the target lamination level identifier, the production board 100 identifier, and the same batch witness sheet group 110 identifier. The action is to establish a unique mapping, and the output is the association record. If the input is missing or conflicting, the output is pre-lamination lockout. S102 is executed by the lamination status acquisition function in the association module 651. Its inputs are the lamination load identifier, the lamination thermal history record, and measurement fields such as the cured thickness and alignment status. The action is to verify the same load or equivalent thermal history, and the output is the pre-state that can enter the hole forming verification. If the record is missing or out of bounds, the output is pre-lamination lockout.

[0108] refer to Figure 4 , Figure 5 , Figure 6 and Figure 7 S103, S104, and S105 are executed by the hole-forming gate control function, interface gate control function, and metallization filling gate control function in the gate control module 652, respectively. Hole-forming gate control function input hole-forming gate control Measurement results and hole window Candidate combinations are compared according to preset criteria for hole shape, open circuit, and pad damage, and the output is given. Continuous qualified parameter zone or pre-drilling lockout; interface gating function input according to the drilling window. Measurement results and desmearing window of the formed desmeared parallel sub-section 112 Candidate conditions are compared based on the residual and interface damage criteria, and the output is given. Locked in the continuous qualified parameter zone or after descaling; the metallization filling gate function input is based on the hole forming window. and removing dirt from windows The measurement results of the formed metallized through-hole parallel sub-piece 113 are first compared. Seed layer state, then compare Hole filling status, output metallization sub-window Fill in the Confucius window and metallized and hole-filled windows Alternatively, it can output the lockout status of the corresponding process stage. If any function detects that the sample identity, previous process window version, or measurement field is incomplete, it will not presume a pass, but will instead output the corresponding abnormal process for review.

[0109] Combination Figure 1 and Figure 7 S106 is executed by the phased release function in the release and traceability module 653, and its input is... , or The pass status and corresponding process window version are used to send the current stage's allowed status and process window version to the corresponding process unit or manual operation terminal, and receive the corresponding receipt; if the parameter exceeds the limit, is restarted repeatedly, or the receipt is missing, it will be restored to locked. S107 is jointly executed by the hierarchical re-verification function in the gating module 652 and the association module 651. Its input is the material batch identifier, lamination load identifier, and cumulative thermal history field of the next target layer level. The action is to create a new association and invalidate the old window that has not been proven to be equivalent. The output is a new task chain from S101 to S106; if the previous level version is mistakenly referenced, the next layer of hole formation will be prevented.

[0110] like Figure 8 As shown, S108 is executed by the final inspection traceability function in the release and traceability module 653. Its inputs are the final inspection results of the production board, the results of the associated reliability samples, and the original records of each gate. Its actions are to establish the association between abnormal results and the relevant process review records and save the handling results. The output is the final inspection status and traceability records. When the sample identity is inconsistent, the samples before and after the thermal cycle are mixed, or the original evidence is missing, the output is the isolation and supplementary review status. Thus, the above three modules, namely the association module 651, the gate module 652, and the release and traceability module 653, can be broken down into sub-functions corresponding to the eight method steps one by one at the software implementation level, without changing the simplified module boundaries in the attached figure.

[0111] refer to Figure 7The three modules mentioned above can function as independent code units within the same application, or they can be distributed among the process controller, server, and field terminals. Modules can exchange status via local process calls, file exchange, or controlled network interfaces, without being limited to any specific software platform or communication protocol. Regardless of the deployment method, the physical essence of the manufacturing process remains unchanged: the process control terminal is responsible for recording, comparing, and releasing data; the lamination unit 200, laser drilling equipment 300, de-drilling unit 400, and metallization and hole-filling unit 500 are responsible for changing the material state of the sheet metal.

[0112] like Figure 7 As shown, the process control terminal 600 can be implemented as an electronic device having a processor 610, a memory 620, a system bus 630, and an interface 640. The processor 610 can be one or more processing units capable of executing general-purpose instructions or control logic; the memory 620 can include volatile storage for running programs and non-volatile storage for storing programs, criteria, and trace records; the system bus 630 connects the processor 610, the memory 620, and the interface 640; the interface 640 connects to... Detection unit 310 Detection unit 410 The controlled input / output terminals of the detection unit 510, the field operation terminal, the lamination unit 200, the laser drilling equipment 300, the descaling unit 400, and the metallization and filling unit 500 are used to receive measurement results and process feedback, and output process parameter versions, release status, or lockout status.

[0113] Combination Figure 7 After the processor 610 reads the instructions from the memory 620, it first calls the association module 651 to establish a material batch-target layer hierarchy mapping, and then calls the gating module 652 to compare. , and Finally, the release and traceability module 653 is invoked to output the release or lockout status. Interface 640 receives measurement result files, status information, or manual verification results from the detection unit and outputs parameter versions and permitted status to the corresponding process unit or field operation terminal. In case of an anomaly, the processor 610 maintains the downstream lockout and saves the received original records until the verification conditions are met.

[0114] refer to Figure 7The electronic equipment can be a field industrial computer, process controller, server, or general-purpose device with the aforementioned computing, storage, and interface capabilities, without limitation on processor model, operating system, database, or network protocol. Even without electronic equipment, controlled paper process cards and physical isolation labels can be used, with recording and verification completed separately by the operator and another independent reviewer to perform the same gating; therefore, electronic equipment is an optional peripheral implementation method and does not constitute a substitute for manufacturing operations such as lamination, laser drilling, desmearing, and electroplating.

[0115] like Figure 7 As shown, the computer-readable storage medium can be a non-volatile storage area in the memory 620, or it can be a solid-state memory, flash memory, electrically erasable programmable read-only memory, magnetic storage medium, or optical storage medium that can be connected to the process control terminal 600. When the program stored on the medium is executed by the processor 610, it enables the process control terminal 600 to complete the material batch-target layer hierarchical association, gating result comparison, step-by-step transmission of process window dependency failure, release or lockout output, and traceability record saving.

[0116] Combination Figure 1 and Figure 7 The program in the storage medium does not directly complete the physical manufacturing of the circuit board in the software environment. Instead, it controls whether the production board 100 can enter the lamination unit 200, the laser drilling equipment 300, the de-drilling unit 400, and the metallization and via filling unit 500, and associates the corresponding parameters with the physical evidence passed through the gate. The manufacturing result is still formed by the board being subjected to heat, laser, chemical, and electrochemical processes.

[0117] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for fabricating a halogen-free high-density interconnect multilayer circuit board, characterized in that, include: Establish the relationship between production boards, material batches, target stacking layers, and witness sheet groups in the same batch. Witness sheet groups in the same batch include physically independent parallel test units for hole forming, parallel test units for de-drilling contamination, and parallel test units for metallization filling. Using each parallel test unit, a hole-forming window, a drill fouling removal window, and a metallization and hole-filling window are established sequentially, and hole-forming gating, interface gating, and metallization and hole-filling gating are executed respectively. The subsequent parallel test unit reconstructs the cumulative preceding state according to all the upstream process windows that have been passed. After each gate is passed, the production board will proceed to the corresponding hole drilling, desmearing, metallization and hole filling processes according to the corresponding process window; when the upstream process window changes, the downstream window and gate evidence formed by the process window will stop being used for release. Parallel test units undergoing destructive testing are sealed and not transferred to the next stage. If any gate fails, the production board is isolated before the corresponding downstream process.

2. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 1, characterized in that: The parallel test unit for hole forming, the parallel test unit for removing drilling debris, and the parallel test unit for metallization filling are respectively the parallel sub-pieces for hole forming, the parallel sub-pieces for removing drilling debris, and the parallel sub-pieces for metallization filling. The production board and the three parallel sub-sheets use the same halogen-free lamination medium batch and the outer copper layer batch and correspond to the same target lamination level. They also meet at least one of the same lamination load conditions and verified equivalent thermal history conditions. The equivalent thermal history is jointly defined by peak temperature, effective heat preservation time, heating and cooling process, board position type and post-curing thickness.

3. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 2, characterized in that: The hole-forming window and the drill-debris removal window are determined by the continuous qualified parameter area in the parameter space composed of at least two candidate factors; the combination of discrete candidate factors with only one item differing by a preset level and the other candidate factors being the same is determined as an adjacent combination; for continuous candidate factors, the adjacent relationship is determined according to the step size or grid spacing determined before the test. A corresponding process window is formed only when multiple adjacent combinations meet the pre-fixed measurement fields, sampling locations, sample quantities, single sample limits, and statistical control limits. Isolated qualified combinations do not form a corresponding process window.

4. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 3, characterized in that: The metallized via filling parallel sub-plate includes a physically separable metallization verification sub-region and a via filling verification sub-region. The two sub-regions reconstruct the previous state according to the hole-forming window and the de-drilling window. The metallization sub-window is determined based on the seed layer continuity detection result of the metallization verification sub-region, and the metallization verification sub-region is sealed after the detection. When the metallized sub-window passes through, the hole-filling verification sub-region reforms the seed layer according to the metallized sub-window and performs hole-filling verification; when the metallized sub-window fails to pass through, the hole-filling verification sub-region does not enter the main filling. When the hole filling verification passes, a hole filling sub-window is formed, which together with the metallization sub-window forms the metallization and hole filling window; when the hole filling verification fails, the metallization and hole filling window is not formed.

5. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 4, characterized in that: The same batch of test pieces adopts at least one of the following: the same production panel edge partitioning setup and the independent accompanying test panel setup; When using a plate-side partitioned setup, each parallel test unit is distinguished from the others by at least one of the following: a cutting groove, a separable connecting bridge, a reserved partition boundary, and a hole array with independent boundaries. Destructive sample preparation operations do not enter the reserved boundaries of other parallel test units. When using an independent accompanying test plate, the independent accompanying test plate satisfies at least one of the same lamination load conditions and verified equivalent thermal history conditions.

6. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 5, characterized in that: The desmearing window is established by at least one of the following routes: wet treatment, plasma treatment, and plasma pretreatment followed by wet treatment. The determination is based on the combined results of thin layer residue at the bottom of the hole, resin shrinkage, glass fiber protrusion, glass fiber etching, damage to the halogen-free deposited dielectric layer, and the surface condition of the captured pad. When establishing metallization and via filling windows, at least one of the following routes is adopted: activated chemical copper plating and direct metallization. Continuous coverage of the via wall and via bottom metallization layers is used as a prerequisite for via filling.

7. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 1, characterized in that: When at least one of the following states occurs: missing test results, inconsistent sample identification with test results, formula version exceeding the corresponding process window, process unit not returning completion receipt, control connection interruption, and emergency equipment shutdown, the downstream process corresponding to the affected gate is locked and the production board is isolated. If the sample identity, actual processing stage, formula version, and interface status can be confirmed through verification, the affected gating will be re-executed based on the confirmed status. If confirmation is not possible, the affected preceding state is reconstructed using a new corresponding parallel test unit, and the affected gating and its downstream gating are re-executed.

8. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 7, characterized in that: For each production board, a traceability record is established. The traceability record includes the production board identification, material batch, target stacking level, lamination load identification, identification of each parallel test unit, drilling window, desmearing window and metallization and filling window version, gate status, equipment and slot line identification, start and end time, completion status and completion receipt. If all the above fields are complete and the review is completed, the gate status is passed and the release status is recorded; if the gate status is failed, the lock status is recorded. If any of the above fields are missing or conflicting, or if the review is not completed, the lock status of the corresponding downstream process is recorded.

9. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 8, characterized in that: The downstream process lockout status is implemented as physical isolation of the production board through at least one of the following: independent isolation rack, sealed bag, controlled flow label, and equipment operation authority; When the gate control is passed and the identity of the parallel test unit, the version of the preceding process window, the test results, and the verification signature in the traceable records are all consistent, the physical isolation of the corresponding stage is lifted. If the gate fails to pass, or if there are inconsistencies between the identity of the parallel test unit, the version of the preceding process window, the test results, and the verification and signing information in the traceability record, the physical isolation shall be maintained and an abnormal process verification record shall be generated.

10. The method for fabricating a halogen-free high-density interconnect multilayer circuit board according to claim 9, characterized in that: The traceable records save the following detection fields: top diameter, bottom diameter, hole depth, hole position offset, hole bottom open status, and captured pad damage data for hole gating micro blind holes; Interface gating captures data on hole bottom residue, resin shrinkage, glass fiber protrusion, glass fiber erosion, halogen-free deposited dielectric layer damage, and pad surface condition and mass change per unit area. The data includes seed layer continuity, voids and seams in the filled copper, orifice depression, orifice bottom interface separation, copper thickness and resistance data for metallized via filling gate, and saves the corresponding sampling location, detection image and classification results.

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