阅读说明：本技术 一种印制板防止树脂塞孔孔破的方法 (Method for preventing hole of resin plug from being broken by printed board ) 是由 从宝龙 郑威 肖德东 黄国平 马东辉 于 2021-09-06 设计创作，主要内容包括：本发明公开了一种印制板防止树脂塞孔孔破的方法,包括以下步骤：在制作生产板次外层的线路层时,一并在其至少一角上制作出一排第一靶标；在设计生产板上的外层线路图形时,在第一靶标的一侧设计出一排第二靶标；在生产板上钻塞孔,在对应第一靶标的位置处钻出孔径小于其的第一检测孔；使塞孔金属化,在塞孔中填塞树脂并固化,通过磨板使板面平整；在生产板上钻出通孔,在对应第二靶标的位置处钻出孔径小于其的第二检测孔；通过x-ray机检测相邻的第一检测孔和第二检测孔在对应的第一靶标和第二靶标上的偏移方向是否一致以及偏移量是否在设计的数值范围内。本发明方法通过增加的靶标和检测孔,在外层钻孔后可以通过X-RAY直观查看两次钻孔的偏移是否符合要求。(The invention discloses a method for preventing a hole of a resin plug from being broken by a printed board, which comprises the following steps: when the circuit layer of the outer layer of the production board is manufactured, a row of first targets are manufactured on at least one corner of the circuit layer; when an outer layer circuit pattern on a production board is designed, a row of second targets are designed on one side of the first targets; drilling a plug hole on the production plate, and drilling a first detection hole with the hole diameter smaller than that of the first target at a position corresponding to the first target; metallizing the plug holes, filling resin in the plug holes and curing, and grinding the board to flatten the board surface; drilling a through hole on the production plate, and drilling a second detection hole with the hole diameter smaller than that of the second target at a position corresponding to the second target; and detecting whether the offset directions of the adjacent first detection hole and the adjacent second detection hole on the corresponding first target and the second target are consistent and whether the offset is within a designed numerical range through an x-ray machine. According to the method, through the added target and the detection hole, whether the deviation of two times of drilling meets the requirement can be visually checked through X-RAY after the outer layer is drilled.)

1. A method for preventing a hole of a resin plug from being broken is characterized by comprising the following steps:

s1, when the circuit layer of the secondary outer layer of the production board is manufactured, a row of first targets are manufactured on at least one corner of the circuit layer of the secondary outer layer; when an outer layer circuit pattern on a production board is designed, a row of second targets which correspond to the first targets one by one are designed on one side of the first targets;

s2, drilling a plug hole to be filled with resin on the production plate, and drilling a first detection hole with the hole diameter smaller than the outer diameter of the first target at the position corresponding to the first target;

s3, sequentially carrying out copper precipitation and full-plate electroplating to metalize the plug hole;

s4, filling resin in the plug holes and curing, and then grinding the board to flatten the board surface;

s5, drilling a through hole on the production board, and drilling a second detection hole with the hole diameter smaller than the outer diameter of the second target at the position corresponding to the second target;

and S6, detecting whether the offset directions of the adjacent first detection hole and the adjacent second detection hole on the corresponding first target and the second target are consistent and whether the offset is within the designed numerical range through an x-ray machine.

2. The method for preventing resin plug hole from being broken according to claim 1, wherein in step S1, a row of first targets and a row of second targets are designed at each of four corners of the production board.

3. The method of claim 1, wherein the first and second inspection holes have the same diameter.

4. The method for preventing resin plug hole from being broken according to claim 3, wherein in step S1, the number of the first targets and the second targets on each corner of the production board is five, five groups of detection targets are formed, and the outer diameters of the first targets and the second targets in each group of detection targets are the same.

5. The method of claim 4, wherein the outer diameters of the five first targets and the five second targets increase sequentially from front to back.

6. The method of claim 5, wherein the outer diameter of the five first targets is greater than the diameter of the first detection hole by 0.075mm, 0.1mm, 0.125mm, 0.15mm and 0.175mm in sequence.

7. The method for preventing the hole of the resin plug from being broken according to any one of claims 4 to 6, wherein in step S6, whether the offset directions of the first detection hole and the second detection hole in each group of detection targets are consistent and the offset amount is within a designed value range is detected by an x-ray machine.

8. The method of preventing the resin plug hole from being broken according to the printed board of claim 1, further comprising the steps between the steps S3 and S4 of:

s31, manufacturing a plated hole pattern on the production board;

and S32, thickening the hole wall copper layer of the plug hole by hole filling electroplating.

9. The method for preventing the resin plug hole from being broken according to the printed board of claim 1, further comprising the following steps after the step S6:

s7, sequentially carrying out copper precipitation and full-plate electroplating to metalize the through holes;

and S8, sequentially carrying out film pasting, exposure and development processes on the production board to form an outer layer circuit pattern, wherein the outer layer circuit pattern comprises circular hole patterns corresponding to the positions of the first target and the second target.

10. The method for preventing the resin plug hole from being broken according to claim 1, wherein the production board is a multi-layer board formed by laminating an inner core board and an outer copper foil together by a prepreg.

Technical Field

The invention relates to the technical field of printed circuit board manufacturing, in particular to a method for preventing a resin plug hole from being broken through a printed circuit board.

Background

In the manufacturing process of the printed circuit board, if the resin plug hole is small and the aspect ratio is large, the resin plug hole is firstly manufactured and then a through hole is drilled, and the process is as follows: the former procedure-drilling resin hole-plugging-copper deposition-plate electricity-hole-plating figure-hole-resin hole-plugging-abrasive belt grinding plate-outer layer drilling-copper deposition-plate electricity-outer layer figure-subsequent procedure, because the hole-plating figure uses the alignment hole of drilling resin hole-plugging and the outer layer figure uses the alignment hole of outer layer drilling, the expansion and shrinkage deviation of the two alignment references in the process can cause the breakage of the resin hole-plugging hole.

The above manufacturing method has the following defects:

1. if the process monitoring is lost, whether the resin drill hole and the outer layer drill hole deviate or not cannot be judged, and whether the deviation meets the requirement or not can be judged;

2. after the outer layer is developed, the deviation from two times of drilling cannot be judged, the deviation from the aligned drilling layer can only be judged, and whether broken holes exist in the resin plug holes cannot be judged.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a method for preventing a resin hole from being plugged and broken by a printed board.

In order to solve the technical problem, the invention provides a method for preventing a resin plug hole from being broken by a printed board, which comprises the following steps:

s1, when the circuit layer of the secondary outer layer of the production board is manufactured, a row of first targets are manufactured on at least one corner of the circuit layer of the secondary outer layer; when an outer layer circuit pattern on a production board is designed, a row of second targets which correspond to the first targets one by one are designed on one side of the first targets;

s2, drilling a plug hole to be filled with resin on the production plate, and drilling a first detection hole with the hole diameter smaller than the outer diameter of the first target at the position corresponding to the first target;

s3, sequentially carrying out copper precipitation and full-plate electroplating to metalize the plug hole;

s4, filling resin in the plug holes and curing, and then grinding the board to flatten the board surface;

s5, drilling a through hole on the production board, and drilling a second detection hole with the hole diameter smaller than the outer diameter of the second target at the position corresponding to the second target;

and S6, detecting whether the offset directions of the adjacent first detection hole and the adjacent second detection hole on the corresponding first target and the second target are consistent and whether the offset is within the designed numerical range through an x-ray machine.

Further, in step S1, a row of first targets and a row of second targets are designed at each of the four corners of the production board.

Further, the first detection hole and the second detection hole have the same hole diameter.

Further, in step S1, the number of the first targets and the second targets on each corner of the production board is five, five sets of detection targets are formed, and the outer diameters of the first targets and the second targets in each set of detection targets are the same.

Further, the outer diameters of the five first targets and the five second targets are sequentially increased from front to back.

Further, the single sides of the outer diameters of the five first targets are sequentially larger than the aperture of the first detection hole by 0.075mm, 0.1mm, 0.125mm, 0.15mm and 0.175 mm.

Further, in step S6, it is detected whether the offset directions of the first detection hole and the second detection hole in each set of detection targets are consistent and the offset amount is within the designed value range by the x-ray machine.

Further, the following steps are included between steps S3 and S4:

s31, manufacturing a plated hole pattern on the production board;

and S32, thickening the hole wall copper layer of the plug hole by hole filling electroplating.

Further, step S6 is followed by the following steps:

s7, sequentially carrying out copper precipitation and full-plate electroplating to metalize the through holes;

and S8, sequentially carrying out film pasting, exposure and development processes on the production board to form an outer layer circuit pattern, wherein the outer layer circuit pattern comprises circular hole patterns corresponding to the positions of the first target and the second target.

Furthermore, the production board is a multilayer board formed by pressing an inner core board and an outer copper foil into a whole through a prepreg.

Compared with the prior art, the invention has the following beneficial effects:

firstly, when a circuit layer of a secondary outer layer of a production board is manufactured, a row of first targets are manufactured on at least one corner of the circuit layer of the secondary outer layer; when an outer layer circuit graph on a production board is designed, a row of second targets which correspond to the first targets one by one are designed on one side of the first targets, then a first detection hole and a second detection hole are drilled in the process of drilling a resin plug hole and an outer layer drilling hole respectively, and an x-ray machine can be used for directly detecting the deviation direction and the deviation amount of the two detection holes on the targets to see whether the deviation of the two times of drilling holes is consistent or not, so that the deviation degree of the two times of drilling holes is monitored, and whether the deviation of the resin plug hole meets the design requirement or not is judged; the array of the first targets and the second targets on each corner are set as five targets with sequentially increased outer diameters, and the numerical range of the offset can be obtained through visual calculation by using a plurality of detection modes with different numerical values, so that whether the offset of the resin plug hole meets the design requirement can be judged more simply and conveniently; when the outer layer graph is manufactured, round hole graphs are formed at positions corresponding to the first target and the second target, so that the deviation degree between the outer layer graph and two times of drilling holes can be visually seen by utilizing the position relation between the round hole graphs and the two detection holes, and the problem that whether hole breakage exists in the resin plug hole after the outer layer circuit is manufactured is judged; the method provided by the invention can monitor the twice drilling expansion and contraction matching and the alignment degree of the outer layer pattern and the twice drilling simultaneously, and effectively improves the yield.

Drawings

FIG. 1 is a schematic illustration of a first target fabricated on a core plate;

FIG. 2 is a schematic illustration of the fabrication of a second target on a production plate;

FIG. 3 is a schematic diagram of five sets of detection targets formed on each corner of a production plate;

FIG. 4 is a schematic illustration of drilling a first and second inspection hole in five sets of inspection targets.

Detailed Description

In order to more fully understand the technical contents of the present invention, the technical solutions of the present invention will be further described and illustrated with reference to specific embodiments.

Examples

The manufacturing method of the circuit board shown in this embodiment includes a variegated ink solder mask process, and sequentially includes the following processing steps:

(1) cutting: the core board is cut according to the size of the jointed board of 520mm multiplied by 620mm, the thickness of the core board is 0.5mm, and the thickness of the copper layers on the two surfaces of the core board is 0.5 oz.

(2) Inner layer circuit manufacturing (negative film process): transferring the inner layer pattern, coating a photosensitive film with a vertical coating machine, controlling the film thickness of the photosensitive film to be 8 μm, completing the exposure of the inner layer circuit by using a full-automatic exposure machine and 5-6 exposure rulers (21 exposure rulers), and forming the inner layer circuit pattern after development; etching an inner layer, etching the exposed and developed core board to form an inner layer circuit, wherein the line width of the inner layer is 3mil, in the process of manufacturing the inner layer circuit, a row of five first targets 1 (shown in figure 1) are manufactured at four corners of the core board at equal intervals, the outer diameters of the five first targets are sequentially increased from front to back, and the specific outer diameters are sequentially 1.15mm, 1.2mm, 1.25mm, 1.3mm and 1.35 mm; and (4) inner layer AOI, and then, detecting defects of an inner layer circuit, such as open short circuit, circuit notch, circuit pinhole and the like, and performing defect scrapping treatment, wherein a defect-free product is discharged to the next flow.

(3) And (3) laminating: the browning speed is that the core plate, the prepreg and the outer layer copper foil are sequentially overlapped according to the requirement (the specific stacking sequence is copper foil, prepreg, core plate, prepreg and copper foil), and then the laminated plate is pressed by selecting proper laminating conditions according to the Tg of the plate material to form a production plate; and in the later stage, when an outer layer circuit pattern on the production board is designed and manufactured, a row of five second targets 2 (shown in fig. 2) corresponding to the first targets one by one are designed on one side of the first targets, five groups of detection targets (shown in fig. 3) consisting of one first target and one second target which correspond to each other are formed, the outer diameters of the first target and the second target in each group of detection targets are the same, namely the outer diameters of the five second targets are 1.15mm, 1.2mm, 1.25mm, 1.3mm and 1.35mm in sequence.

(4) Drilling a resin plug hole: according to the existing drilling technology, a hole to be filled with resin is drilled on a production board according to the design requirement by using a 1.0mm drill point, and a first detection hole 3 (shown in fig. 4) is drilled at the center position corresponding to a first target, namely the hole diameter of the first detection hole is 1mm, and the single sides of five first detection holes on each corner are sequentially smaller than the corresponding first target by 0.075mm, 0.1mm, 0.125mm, 0.15mm and 0.175 mm.

(5) Copper deposition: and (3) depositing a layer of thin copper on the plate surface and the hole wall by using an electroless copper plating method, and testing the backlight to 10 grades, wherein the thickness of the deposited copper in the hole is 0.5 mu m.

(6) Electroplating the whole plate: and performing full-plate electroplating for 20min at the current density of 18ASF to increase the thickness of the hole copper and the plate surface copper layer.

(7) Plating a hole pattern: and pasting a film on the production board, and windowing at the position corresponding to the plug hole after exposure and development in sequence to form a plated hole pattern.

(8) Hole filling and electroplating: and the hole wall copper layer of the plug hole is thickened through hole filling electroplating.

(9) Resin hole plugging: filling resin in the plug holes and curing, and then removing the resin protruding out of the plate surface through a belt sanding plate to flatten the plate surface.

(10) Drilling an outer layer: according to the existing drilling technology, a through hole is drilled on a production plate according to the design requirement by using a 1.0mm drill point, and a second detection hole 4 (shown in fig. 4) is drilled at the central position corresponding to the post-production second target, namely the aperture of the second detection hole is 1mm, and the single sides of the five second detection holes on each corner are sequentially smaller than the corresponding second target by 0.075mm, 0.1mm, 0.125mm, 0.15mm and 0.175 mm.

(11) And (3) detection: firstly, introducing a designed outer layer pattern into an x-ray machine and aligning the outer layer pattern with a production plate so as to directly identify the position of a second target in the x-ray machine, and detecting whether the offset directions of adjacent first detection holes and second detection holes on the corresponding first target and second target are consistent and whether the offset is in a numerical range required by design through the x-ray machine so as to monitor the offset degree of two times of drilling and judge whether the offset of resin plug holes meets the design requirement; the first targets and the second targets in each row are set as five targets with sequentially increased outer diameters, so that the maximum offset and the minimum offset of the two detection holes can be seen, the number range of the offset can be intuitively calculated by using a plurality of detection modes with different values, for example, the second detection hole deviates from the range of the corresponding target, the third detection hole does not deviate from the range of the corresponding target, namely, the deviation is 0.1-0.125mm, other values are judged in the same way, and whether the offset of the resin hole plugging meets the design requirement can be more simply and conveniently judged.

(12) Copper deposition: and (3) depositing a layer of thin copper on the plate surface and the hole wall by using an electroless copper plating method, and testing the backlight to 10 grades, wherein the thickness of the deposited copper in the hole is 0.5 mu m.

(13) Electroplating the whole plate: and performing full-plate electroplating for 60min at the current density of 18ASF to increase the thickness of the hole copper and the plate surface copper layer.

(14) Manufacturing an outer layer circuit (positive process): transferring an outer layer pattern, namely, completing the exposure of the outer layer circuit by using a full-automatic exposure machine and a positive film circuit film and using a 5-7-grid exposure ruler (21-grid exposure ruler), developing to form the outer layer circuit pattern on a production plate, wherein the outer layer circuit pattern comprises round hole patterns corresponding to the positions of a first target and a second target, and the deviation degree of the outer layer pattern and twice drilled holes can be visually seen by observing the deviation direction and the deviation amount of the first detection hole and the second detection hole in the corresponding round hole patterns, namely, the alignment degree of the outer layer pattern and the twice drilled holes is monitored, and finally whether resin plug holes meet the requirement of the IPC minimum hole ring after the outer layer circuit is manufactured is judged, so that whether the problem of hole breakage exists in the resin plug holes or not is solved; electroplating an outer layer pattern, then respectively plating copper and tin on the production plate, setting electroplating parameters according to the required finished copper thickness, wherein the copper plating is carried out for 60min at the current density of 1.8ASD, and the tin plating is carried out for 10min at the current density of 1.2ASD, and the tin thickness is 3-5 mu m; then sequentially removing the film, etching and removing tin, etching an outer layer circuit on the production plate, and forming a first target and a second target in the circular hole pattern of the wafer; and the outer layer AOI uses an automatic optical detection system to detect whether the outer layer circuit has the defects of open circuit, gap, incomplete etching, short circuit and the like by comparing with CAM data.

(15) Solder resist and silk screen printing of characters: after the solder resist ink is silk-screened on the surface of the multilayer board, the solder resist ink is cured into a solder resist layer through pre-curing, exposure, development and thermosetting treatment in sequence; specifically, the TOP surface solder resist ink is added with a UL mark on the TOP surface character, so that a protective layer which prevents bridging between circuits during welding and provides a permanent electrical environment and chemical corrosion resistance is coated on the circuits and the base materials which do not need welding, and the protective layer plays a role in beautifying the appearance.

(16) Surface treatment (nickel-gold deposition): the copper surface of the welding pad at the solder stop windowing position is communicated with a chemical principle, a nickel layer and a gold layer with certain required thickness are uniformly deposited, and the thickness of the nickel layer is as follows: 3-5 μm; the thickness of the gold layer is as follows: 0.05-0.1 μm.

(17) And electrical test: testing the electrical conduction performance of the finished board, wherein the board use testing method comprises the following steps: and (5) flying probe testing.

(18) And forming: according to the prior art and according to the design requirement, routing the shape, and obtaining the circuit board with the external tolerance of +/-0.05 mm.

(19) FQC: according to the customer acceptance standard and the inspection standard of my department, the appearance of the circuit board is inspected, if a defect exists, the circuit board is repaired in time, and the excellent quality control is guaranteed to be provided for the customer.

(20) FQA: and (5) measuring whether the appearance, the hole copper thickness, the dielectric layer thickness, the green oil thickness, the inner layer copper thickness and the like of the circuit board meet the requirements of customers or not again.

(21) And packaging: and hermetically packaging the circuit boards according to the packaging mode and the packaging quantity required by customers, putting a drying agent and a humidity card, and then delivering.

In other embodiments, the first target is fabricated in step (2) on only one of the surfaces of the core plate, and the second target is fabricated in the production plate only on the outer layer circuit next to the first target circuit layer.

The technical solutions provided by the embodiments of the present invention are described in detail above, and the principles and embodiments of the present invention are explained herein by using specific examples, and the descriptions of the embodiments are only used to help understanding the principles of the embodiments of the present invention; meanwhile, for a person skilled in the art, according to the embodiments of the present invention, there may be variations in the specific implementation manners and application ranges, and in summary, the content of the present description should not be construed as a limitation to the present invention.