Processing method of through-blind integrated PCB and PCB
By using the method of graded plug holes and primary copper plating in the processing process of blinded integrated PCB, the problems of complex process and poor quality in the existing technology are solved, and process simplification, efficiency improvement and product quality improvement are achieved.
Patent Information
- Application Number
- CN202510120507.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-25
- Publication Date
- 2025-04-25
AI Technical Summary
In the prior art, the processing technology of the blind integrated PCB is complex, the process is long, and the reliability and quality is poor, especially in the plug process, there are problems such as complex operation and uneven copper thickness.
The graded plug hole process is adopted, and the blind hole and VIPPO hole are divided into the blind hole and VIPPO hole are carried out through the dispenser. Combined with the primary electroplating copper process, the second drilling and electroplating process is reduced and the process is simplified.
The processing process is simplified, the operation efficiency and product quality are improved, the uniformity of copper thickness and the IPC Class3 level requirements of corner copper are ensured, and the reliability of the product is enhanced.
Smart Images
Figure CN119893885A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of printed circuit boards, and in particular to a method for processing a through-blind integrated PCB and the PCB. Background Art
[0002] In the PCB processing and manufacturing process, plugging is a very critical process. The BGA key functional area is designed on the PCB board, and there is a plate-in-hole design at the BGA position. The main purpose is to save the wiring aperture of the patch to achieve higher density wiring; it can also prevent the solder from penetrating the component surface from the via during wave soldering during assembly to cause a short circuit; it can also prevent the hole wall oxidation during the use of the PCB. As we all know, there are many ways to plug holes, including electroplating filling holes, resin plugging holes, ink plugging holes, etc. Different product designs correspond to different plugging methods. For the high aspect ratio through-blind integrated design PCB resin plugging method, the common processing method is to uniformly use a vacuum resin plugging machine to solve the problem of different plugging depths of through-blind holes and small-diameter plugging holes. However, this single processing method has obvious disadvantages, such as complex operation, long process, poor reliability and quality, etc. Its disadvantages are specifically reflected in: Vacuum plugging is the printing plugging of the whole board surface. The holes that do not need to be plugged need to be reprocessed by double drilling, which is a long process. Under the requirement of copper for the first and second drilling holes, the overall copper is relatively thick after electroplating, which increases the difficulty of pattern etching. Under the premise of ensuring that etching can be operated, the first electroplating copper thickness of the plugged VIPPO hole is relatively thin, which leads to the risk of insufficient copper at the corner of the POFV hole when the copper surface is ground after plugging, and the product reliability performance is relatively poor. Summary of the invention
[0003] The purpose of the present application is to provide a method for processing a through-blind integrated PCB and a PCB to solve the defects of the prior art that lead to complex operation, long process and poor reliability and quality.
[0004] In order to achieve the above objectives, this application is implemented by adopting the following technical solutions: In a first aspect, the present application discloses a method for processing a through-blind integrated PCB, which comprises the following steps: manufacturing a first substrate; Laminating a plurality of first substrates to form a second substrate, and opening a blind hole on the first substrate on the outer layer of the second substrate; Performing a hole-drilling operation on the second substrate to form all through holes connecting the inner and outer layer circuits; Performing a first electroplating on the through hole, the blind hole and the surface of the second substrate; Performing graded plugging operations on the VIPPO holes in the blind holes and through holes; The second substrate after plugging the holes is subjected to a second electroplating to obtain a pre-processed PCB; The pre-processed PCB is processed by circuit manufacturing and ink surface printing to obtain the through-blind integrated PCB.
[0005] Further solutions of this application, When the first substrate is manufactured, an image manufacturing process is performed, including The corresponding pattern is produced on each first substrate by pressing the dry film, exposing the inner layer and transferring the developing image.
[0006] In a further solution of the present application, the step of opening a blind hole on the first substrate on the outer layer of the second substrate further comprises: The blind holes are positioned by developing the blind hole coordinates on the surface of the first outer substrate using an LDI image transfer method, and burning corresponding blind holes at the blind hole coordinate positions using a CO2 laser burning method.
[0007] Further solutions of this application, The graded plugging operation includes primary plugging and secondary plugging; During the first-level plugging operation, the blind hole is plugged to form a blind hole resin plugged hole; During the secondary plugging, the VIPPO holes among the plurality of through holes are plugged by selective plugging.
[0008] In a further solution of the present application, the plugging operation is performed by a glue dispenser, and the plugging operation of the blind hole includes: Put the second substrate after the first electroplating onto the machine; pre-position the second substrate; accurately position it through CCD vision; set the dispensing head parameters; dispense glue on the front side of the second substrate; wait for the glue on the front side to solidify before dispensing glue on the back side; perform AOI inspection after the back side is solidified; the system automatically repairs the defective position.
[0009] In a further solution, the graded plugging operation process is carried out in a vacuum dispensing environment.
[0010] In a further solution of the present application, the circuit making process includes: The outer layer pattern is produced on the pre-processed PCB using a full-board imaging method according to the circuit diagram.
[0011] In a further embodiment of the present application, the ink surface printing process comprises: The pre-PCB panel is printed with ink, and after printing, it is short-baked and then exposed, developed, and long-baked to complete the solder mask ink processing on the entire board.
[0012] In a further embodiment of the present application, the processing method further comprises Electrical functional test processing, after the pre-processed PCB is processed by the circuit making processing and the ink surface printing processing, it is further processed by electrical functional test processing to obtain a qualified through-blind integrated PCB.
[0013] In a second aspect, a PCB is manufactured by the above-mentioned through-blind integrated PCB processing method.
[0014] The beneficial effects of this application are: The design scheme of this application simplifies the process. For the blind and through-hole integrated design part number, the blind holes and VIPPO holes in the through holes are used in the plugging process for graded plugging operations (blind holes are plugged with glue and VIPPO holes are drilled and then selective plugging is used instead of vacuum plugging blind holes). Other through holes that are not plugged are processed by double drilling. By reducing the process of double drilling and electroplating double drilling during the optimization process, the operation efficiency is improved, which will have a great positive contribution to the process economy. In addition, in terms of processing difficulty, through a single copper electroplating process, the overall copper thickness is reduced and the copper thickness uniformity is improved, which reduces the difficulty of etching and improves the etching pass rate. In terms of product quality, the attack of mechanical grinding on the copper thickness of the VIPPO corner copper is reduced, which can meet the IPC Class 3 level requirements of the corner copper, and the reliability is well guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a flow chart of a method for processing a through-blind integrated PCB in Embodiment 1 of the present application; Figure 2 This is a schematic flow chart of a method for processing a through-blind integrated PCB in another embodiment of the present application; Figure 3 This is a schematic diagram of a blind via and a VIPPO hole in a through-blind integrated PCB of Example 2; Figure 4 This is a schematic diagram of the blind vias and VIPPO holes in the through-blind integrated PCB of Example 2 after the first electroplating; Figure 5 This is a schematic diagram of the second electroplating process after the selective hole-piercing in the through-blind integrated PCB in Example 2 of the present application. DETAILED DESCRIPTION
[0016] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use. Embodiment 1
[0017] like Figure 1As shown, this embodiment discloses a method for processing a through-blind integrated PCB, which includes: manufacturing a first substrate; Laminating a plurality of first substrates to form a second substrate, and opening a blind hole on the first substrate on the outer layer of the second substrate; Performing hole drilling operation on the second substrate to process all through holes connecting the inner and outer layer circuits; Performing first electroplating on the through hole, the blind hole and the surface of the second substrate; Perform graded plugging operations on VIPPO holes in blind holes and through holes; The second substrate after plugging the holes is subjected to a second electroplating to obtain a pre-processed PCB; The pre-processed PCB is processed by circuit making and ink surface printing to obtain the through-blind integrated PCB.
[0018] In some embodiments, a method for processing a through-blind integrated PCB is specifically implemented as follows; 1) First substrate production: producing corresponding patterns on each first substrate by pressing dry film, inner layer exposure & development image transfer; 2) First substrate lamination: According to the product stacking structure, multiple first substrates are laminated, specifically the corresponding PP (adhesive sheet) and Core are laminated together, and then laminated using a press; 3) Production of circular blind holes in the outer layer: Use LDI image transfer method on the first substrate of the outer layer to develop the position (coordinates) of the blind holes on its board surface, so as to accurately locate the position of the blind holes; 4) Laser drilling: CO2 laser drilling is used to burn the corresponding blind holes on the outer surface of the second substrate; 5) Mechanical drilling: All through holes (including VIPPO holes and VIA holes) connecting the inner and outer layer circuits are drilled on the second substrate by mechanical drilling. 6) Electroplating copper: electroplating all through holes and blind holes as well as the surface of the second substrate with conductor copper; 7) Resin plugging: Use a glue dispenser to fill the blind hole with glue to achieve blind hole resin plugging. After the blind hole resin is plugged, use the selective plugging method to plug the VIPPO hole. After plugging the hole, there will be resin residue on the board surface and the edge of each hole. Use a horizontal ceramic brush to grind the resin to ensure the board surface is clean; 8) Cap plating: The conductor is covered on the surface of the hole after the resin plugging through electroplating. At the same time, some through-hole operations are crimped. The number is set according to actual needs, and the hole diameter meets the crimping requirements. In this process, the pre-processed PCB is obtained after electroplating; 9) Circuit production: Use the full-board imaging method to produce the outer layer graphics on the pre-processed PCB according to the circuit diagram; 10) Ink surface printing: pre-treat the PCB for ink printing, perform short baking after printing, and then complete the solder mask ink processing on the entire board through processes such as exposure, development, and long baking; 11) Finished product: The finished product is formed through molding, surface treatment, and electrical functional testing.
[0019] Among them, in steps 5) & 7), all the via holes on the second substrate are processed by drilling once, and there is no need to drill other through holes that do not need to be plugged, which simplifies the process. Use glue dispensing to plug blind holes separately, and use a selective plugging machine to plug VIPPO through holes according to their aspect ratio using appropriate printing parameters. Dispensing machine plugging method: On-machine ==》Pre-positioning ==》CCD vision precision positioning ==》Dispensing head parameter setting ==》Front-side dispensing ==》Curing ==》Back-side dispensing ==》Curing ==》AOI inspection (2D & 3D dimension inspection) ==》Automatically repair defective positions ==》Off-machine
[0020] Dispensing machine processing advantages: A. Positioning method: using double dispensing valves, the CCD vision system calculates the distance between the two points, the main valve follows the Z-axis movement, and the auxiliary valve automatically adjusts the distance between the main and auxiliary valves according to the calculated distance, and performs high-precision dispensing. At the same time, it has positioning focal length compensation (to solve the problem of uneven products and unclear positioning images), and controls the positioning accuracy within + / -1mil B.UV curing: curing is done online after dispensing, no additional baking is required, improving processing efficiency C. Weighing system: Dispense a certain number of glue points and calculate the glue amount at a single point.
[0021] According to the customer's dispensing quantity requirements, the dispensing speed is calculated through logical operations to achieve single-point glue quantity control D. Laser height measurement: Combined with logic, the distance between the nozzle and the product is accurately calculated to ensure the dispensing height and frequency. Currently, the dispensing efficiency can reach 500 points / second. E. Motion mechanism: Rotation mechanism (90° rotating cylinder + vertical motor); mainly used for side dispensing, rotation angle ±45° When dispensing 0.15mm blind holes, the setting parameters of the dispensing machine are as shown in Table 1; ; Table 1 When dispensing glue for VIPPO holes of 0.2mm, the setting parameters of the dispensing machine are as shown in Table 2; ; Table 2 The present application provides a new resin plugging method for common blind and through holes, which mainly uses glue dispensing to achieve individual plugging of blind holes, which can reduce product delivery time and better ensure product quality, and will have obvious advantages in improving the overall market competitiveness of major products. Embodiment 2
[0022] This embodiment provides a PCB, which is manufactured according to the processing method of the through-blind integrated PCB in the above-mentioned embodiment 1; the effect of the product is the same as that of the embodiment 1, which will not be repeated here.
[0023] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", etc. are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.
[0024] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.
Claims
1. A method for processing a through-blind integrated PCB, characterized in that: include: manufacturing a first substrate; Laminating a plurality of first substrates to form a second substrate, and opening a blind hole on the first substrate on the outer layer of the second substrate; Performing a hole-drilling operation on the second substrate to form all through holes connecting the inner and outer layer circuits; Performing a first electroplating on the through hole, the blind hole and the surface of the second substrate; Performing graded plugging operations on the VIPPO holes in the blind holes and through holes; The second substrate after plugging the holes is subjected to a second electroplating; Obtaining pre-processed PCB; The pre-processed PCB is processed by circuit manufacturing and ink surface printing to obtain the through-blind integrated PCB.
2. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: When the first substrate is manufactured, an image manufacturing process is performed, including The corresponding pattern is produced on each first substrate by pressing the dry film, exposing the inner layer and transferring the developing image.
3. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The step of opening a blind hole on the first substrate in the outer layer of the second substrate further comprises: The blind holes are positioned by developing the blind hole coordinates on the surface of the first outer substrate using an LDI image transfer method, and burning corresponding blind holes at the blind hole coordinate positions using a CO2 laser burning method.
4. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The graded plugging operation includes primary plugging and secondary plugging; During the first-level plugging operation, the blind hole is plugged to form a blind hole resin plugged hole; During the secondary plugging, the VIPPO holes among the plurality of through holes are plugged by selective plugging.
5. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The plugging operation is performed by a glue dispenser, and the plugging operation of the blind hole includes: Put the second substrate after the first electroplating onto the machine; pre-position the second substrate; accurately position it through CCD vision; set the dispensing head parameters; dispense glue on the front side of the second substrate; wait for the glue on the front side to solidify before dispensing glue on the back side; perform AOI inspection after the back side is solidified; the system automatically repairs the defective position.
6. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The graded plugging operation process is carried out in a vacuum dispensing environment.
7. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The line making process includes: The outer layer pattern is produced on the pre-processed PCB using a full-board imaging method according to the circuit diagram.
8. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The ink surface printing process comprises: The pre-PCB panel is printed with ink, and after printing, it is short-baked and then exposed, developed, and long-baked to complete the solder mask ink processing on the entire board.
9. The method for processing a through-blind integrated PCB according to claim 1, characterized in that: The processing method also includes Electrical functional test processing, after the pre-processed PCB is processed by the circuit making processing and the ink surface printing processing, it is further processed by electrical functional test processing to obtain a qualified through-blind integrated PCB.
10. A PCB, characterized in that: It is manufactured by the processing method of the through-blind integrated PCB as described in any one of claims 1 to 9 above.