Manufacturing method for enhancing heat dissipation of groove body electroplating plug copper block for PCB (Printed Circuit Board)

Abstract

The invention discloses a manufacturing method for enhancing heat dissipation by electroplating a groove body and plugging a copper block for a PCB (Printed Circuit Board), which comprises the following steps of: manufacturing target holes: after a multi-layer board is formed through browning and pressing, designing alignment target holes of the multi-layer board among patterns of a board body through punching equipment; a drilling step: drilling pattern holes of the board body by using drilling equipment to form conduction among layers, and drilling four conduction holes in a copper block groove; a groove milling step: performing groove milling on the copper block groove after positioning by using the target hole through a numerical control milling machine; a copper deposition and electroplating step: performing copper deposition in the copper block groove and the via hole, and performing thick copper plating in the copper block groove and the via hole through primary copper electroplating; hole plugging: plugging a copper block into a copper block groove matched with the copper block, and plugging copper paste into a gap between the copper block groove and the copper block; and a high-temperature baking step: baking and curing the copper paste and the copper block at a high temperature. The problems that in the prior art, the heat dissipation function of a PCB cannot be maximized, and a board with the high heat dissipation requirement cannot be met are solved.

Description

Technical Field

[0001] The invention relates to the field of PCB processing and manufacturing, and in particular to a method for manufacturing a slot electroplating copper plug for PCB to enhance heat dissipation. Background Art

[0002] For electronic devices, a certain amount of heat will be generated when working, which will cause the internal temperature of the device to rise rapidly. If the heat is not dissipated in time, the device will continue to heat up, the device will fail due to overheating, and the reliability of the electronic equipment will decrease. Therefore, it is very important to perform good heat dissipation treatment on the circuit board.

[0003] In the prior art, for the production of high heat dissipation products, a copper block is embedded in the PCB board. Under high power and long-term uninterrupted operation conditions, the copper block is used to enhance the heat dissipation function to prevent abnormal signals or abnormalities caused by heating of the board. At present, most factories have the following two production schemes: first, the board is pressed normally, and after pressing, the copper block groove is opened by CNC milling, the copper block is fixed in the groove, and then the copper block is fixed by plugging resin. Although this method can increase the heat dissipation of the board to a certain extent, the groove is connected by resin all around, and there is no inner layer through the line conduction, which has certain limitations, and the heat dissipation function cannot be maximized, and it cannot meet the requirements of boards with high heat dissipation; before pressing, the relevant core board and PP are opened by CNC milling, and then the copper block is inserted by fusion plate, and the copper block is fixed by pressing PP flow glue. This scheme has the same problem as the first scheme, that is, the board is still connected to the copper block by PP glue, and the board circuit can only be connected to the copper block through the surface layer, and the function of the board with high heat dissipation requirements cannot be realized.

[0004] In view of this, the technical scheme proposes a method for manufacturing a PCB slot body electroplated copper plug to enhance heat dissipation. The slot body (including Cav it i or through slot) is first subjected to copper deposition and electroplating methods, and then plugged with copper paste (copper paste has better conductivity than resin or PP glue. By plugging copper blocks with copper paste, all inner and outer layers can be connected to the greatest extent, and then connected to the copper blocks through the conductive effect of copper paste). The inner related circuit layers form an effective connection through electroplated copper-plugging copper paste-copper blocks, which can achieve high heat dissipation requirements to the greatest extent. Summary of the invention

[0005] The technical solution of the present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the main purpose of the present invention is to provide a method for manufacturing a copper block for electroplating a slot body of a PCB to enhance heat dissipation, aiming to solve the problem that the heat dissipation function of the PCB in the prior art cannot be maximized and cannot meet the problem of high heat dissipation requirements.

[0006] To achieve the above-mentioned purpose, the present invention provides a method for manufacturing a copper block for electroplating a slot of a PCB to enhance heat dissipation, including target hole manufacturing. After a multilayer board is formed through browning and lamination, a target hole for positioning the multilayer board is designed between the patterns of the board body through a punching device;

[0007] A drilling step, using a drilling device to drill pattern holes on the board to form conduction between layers, and drilling four conduction holes in the copper block groove;

[0008] A gong groove step, using a CNC gong machine to position the target hole and then gong the copper block groove;

[0009] The copper electroplating step adopts chemical copper deposition to deposit copper in the copper block groove and the conductive hole, and then electroplates the copper block groove and the conductive hole with thick copper;

[0010] A plugging step, placing the plate body on a plugging mesh plate, plugging a copper block into a matching copper block groove, and then plugging copper paste into a gap between the copper block groove and the copper block;

[0011] The high temperature baking step is to bake and solidify the copper paste and copper block at high temperature.

[0012] As a further solution of the present invention, in the target hole manufacturing step, before the browning and pressing process, the following pre-processing steps are also included:

[0013] Cutting the plate to a fixed size by a cutting machine;

[0014] Transferring the circuit pattern to the board through coating and exposure of printed circuits, and then obtaining the pattern through etching;

[0015] Through optical detection, check whether the board circuit has defects.

[0016] As a further solution of the present invention, in the grooving step, a flat-bottomed grooving cutter is used to grooving the copper block groove.

[0017] As a further solution of the present invention, after the gong groove is formed, a depth measuring instrument and a two-dimensional detection instrument are used to perform a standard test of the copper block groove with a tolerance accuracy of ±0.1mm.

[0018] As a further solution of the present invention, in the copper electroplating step, the thickness of the electroplated copper ranges from 18um to 20um.

[0019] As a further solution of the present invention, in the plugging step, the high temperature curing is performed at a temperature between 120° C. and 160° C., and the duration is between 1.5 h and 2.5 h.

[0020] As a further solution of the present invention, after high-temperature curing, the excess copper slurry is ground flat using a ceramic grinding plate.

[0021] The beneficial effects of the present invention are as follows:

[0022] The present invention proposes a method for manufacturing a slot body electroplated copper block for PCB to enhance heat dissipation. The method first performs copper deposition-electroplating on the slot body (including the cavity or through slot), and then uses copper paste plugging (copper paste has better conductive performance than resin or PP glue. By plugging copper blocks with copper paste, all inner and outer layers can be connected to the greatest extent), and then connects with the copper blocks through the conductive effect of copper paste, so as to achieve high heat dissipation requirements to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the technical solutions of the present invention or the technical solutions of the present invention in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the technical solutions of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0024] Figure 1 It is a schematic diagram of the implementation process of the present invention.

[0025] Figure 2 It is a cross-sectional schematic diagram of the actual situation of implementing the copper block electroplating plug process of the present invention.

[0026] Figure 3 It is a schematic diagram of the overall implementation process of the method of the present invention when it is actually carried out.

[0027] Figure 4 Schematic diagram of hole distribution when drilling holes in a plate body according to the method of the present invention. DETAILED DESCRIPTION

[0028] as follows:

[0029] Please see attached Figure 1-4 ,

[0030] The main implementation steps include target hole production. After the multilayer board is formed through browning and lamination, the alignment target holes of the multilayer board are designed between the patterns of the board body through the punching equipment;

[0031] Drilling step: using drilling equipment to drill pattern holes on the board to form conduction between layers, and drilling 4 conduction holes in the copper block groove;

[0032] (Use a drill to drill the holes of the designed pattern to form via holes between layers. At the same time, four via holes need to be drilled in the Cav it i to connect the Cav it i through the holes, so that the subsequent copper paste plugging can plug the copper paste into the cavity without bubbles or cavities)

[0033] Gong grooving step, using a CNC gong machine to position the copper block groove using a target hole;

[0034] The copper electroplating step adopts chemical copper plating to deposit copper in the copper block groove and the conductive hole, and then electroplating copper to plate thick copper in the copper block groove and the conductive hole;

[0035] The plugging step is to place the board body on the plugging stencil, plug the copper block into the matching copper block groove, and then plug the copper paste into the gap between the copper block groove and the copper block;

[0036] The high temperature baking step is to bake and solidify the copper paste and copper block at high temperature.

[0037] Considering all the actual processes, the overall production process is: cutting - inner layer graphics - inner layer AOI - browning - matching - pressing - target hole - drilling edge - drilling Cav it i slot (or through slot) - copper deposition - electroplating - plugging - grinding - post-process. Cutting, use a cutting machine to cut the production board to a fixed size, regular size: 18*20inch; inner layer graphics, transfer the required graphics to the board through coating and exposure of printed circuits, and then obtain the graphics through etching; inner layer AOI, use AOI optical inspection to check whether there are defects in the PCB board circuit; browning, use browning solution to roughen the copper surface of the PCB board to enhance the bonding between the copper surface and PP; pressing, use a press to combine each PCB substrate to form a multi-layer PCB;

[0038] (After the above board process, the following copper block plugging process is carried out after electroplating)

[0039] Target hole punching, through the target hole designed between the graphics, a multi-layer PCB board is formed for alignment, and the target hole is drilled as the subsequent alignment; drilling, using a drill to drill the holes of the designed graphics to form vias between the layers, and at the same time, 4 via holes need to be drilled in the Cav iti, and the Cav iti is connected through the hole to facilitate the subsequent copper paste plugging hole. The copper paste can be plugged into the cavity so that there are no bubbles or cavities; gong Cav iti groove, this groove is the most critical production of the present invention, through the CNC numerical control gong machine, the target hole is used for position fixing, the Cav iti cavity / groove designed by the customer is gonged out by the depth control method, and the length / width / depth of the Cav iti cavity / groove (if any) is gonged by the gong cutter. The gong groove must be made with a flat-bottomed gong cutter to control the flatness of the bottom of the groove. After the CNC milling groove is made by CNC, a depth gauge and a two-dimensional detection instrument are used to calibrate the Cav iti i or the length / width / depth of the groove (if any) are checked for compliance, and the dimensional tolerance control is made according to the customer's design ±0.1mm; copper deposition / electroplating, the Cav iti cavity / groove is deposited with a layer of copper in the Cav iti cavity / groove and the through-hole by chemical copper deposition, and then a thicker layer of copper is electroplated in the Cav iti cavity / groove by PTH electroplating. The electroplated copper thickness is usually made according to 18 / 20um. A layer of copper is electroplated on the Cav iti cavity / groove. This layer of copper will have a better conductive property between the subsequent copper block and the Cv iti cavity / groove, and will have better heat dissipation; plugging, through selective plugging, a plugging stencil is made, the PCB board is placed on the plugging stencil, and the pre-customized copper block is inserted into the electroplated Cav iti cavity / groove by embedding the copper block, and then the copper paste is plugged into the Cac iti cavity / groove by plugging. i cavity gap / groove, and then high temperature baking at 150℃*2h to fix the copper paste and the copper block. After high temperature curing, the excess copper paste is ground flat with a ceramic grinding plate to obtain a Cv iti or through-groove electroplating and copper block plugging product.

[0040] A preferred embodiment of the present invention: in the target hole making step, before the browning and pressing process, the following pre-processing steps are also included:

[0041] Cut the board to a fixed size using a cutting machine;

[0042] The circuit pattern is transferred to the board through coating and exposure of the printed circuit, and then the pattern is obtained by etching;

[0043] Use optical inspection to check whether there are any defects in the board circuit.

[0044] A preferred embodiment of the present invention: in the gong grooving step, a flat-bottomed gong cutter is used to gong the copper block groove.

[0045] A preferred embodiment of the present invention: after the gong groove is formed, a depth measuring instrument and a two-dimensional detection instrument are used to perform a standard detection of the copper block groove with a tolerance accuracy of ±0.1mm.

[0046] A preferred embodiment of the present invention: in the copper electroplating step, the thickness of the electroplated copper ranges from 18um to 20um.

[0047] The Cav iti cavity / groove is deposited with a layer of copper in the Cav iti cavity / groove and through-hole by chemical copper deposition, and then a thicker layer of copper is electroplated in the Cav iti cavity / groove by PTH electroplating. The thickness of the electroplated copper is usually 18 / 20um.

[0048] The production board is cut into fixed sizes by a cutting machine, and the regular size is 18*20inch.

[0049] A preferred embodiment of the present invention: in the plugging step, the high temperature curing is performed at a temperature between 120°C and 160°C, and the duration is between 1.5h and 2.5h.

[0050] A preferred embodiment of the present invention is as follows: after high temperature curing, the excess copper slurry is ground flat using a ceramic grinding plate.

[0051] The above are only preferred embodiments of the technical solution of the present invention, and do not limit the patent scope of the technical solution of the present invention. All equivalent structural changes made by using the contents of the technical solution description and drawings of the present invention under the conception of the technical solution of the present invention, or directly / indirectly used in other related technical fields are included in the patent protection scope of the technical solution of the present invention.

Claims

1. A method for manufacturing a copper block for electroplating a slot of a PCB to enhance heat dissipation, characterized in that: The steps include: S1. Target hole production, After the multilayer board is formed by browning and lamination, the multilayer board is designed with the target holes between the patterns of the board body by punching equipment; S2, drilling steps, The pattern holes of the board are drilled by drilling equipment to form conduction between the layers, and four conduction holes are drilled in the copper block groove; S3, gong groove step, After positioning using the target hole, the copper block groove is grooved by a numerically controlled grooving machine; S4, copper electroplating step, Copper is deposited in the copper block groove and the conductive hole by chemical copper deposition, and thick copper is plated in the copper block groove and the conductive hole by electroplating copper once more; S5, plugging step, The plate body is placed on the plug-hole mesh plate, a copper block is inserted into the copper block groove matched therewith, and then copper paste is inserted into the gap between the copper block groove and the copper block; S6, high temperature baking step, The copper paste and copper block are baked and solidified at high temperature.

2. The method for manufacturing a slot electroplated copper plug for PCB to enhance heat dissipation according to claim 1, characterized in that: In the target hole production step, before the browning and pressing process, the following pre-processing steps are also included: A1. Cutting the plate to a fixed size by a cutting machine; A2, transferring the circuit pattern to the board through coating and exposure of the printed circuit, and then obtaining the pattern by etching; A3. Check whether there are any defects in the board circuit by optical inspection.

3. The method for manufacturing a slot electroplated copper plug for PCB to enhance heat dissipation according to claim 1, characterized in that: In the grooving step, a flat-bottomed grooving cutter is used to grooving the copper block groove.

4. The method for manufacturing a slot electroplated copper plug for PCB to enhance heat dissipation according to claim 3, characterized in that: After the grooving, a depth measuring instrument and a two-dimensional detection instrument are used to perform standard inspection on the copper block groove with a tolerance accuracy of ±0.1mm.

5. The method for manufacturing a slot electroplated copper plug for PCB to enhance heat dissipation according to claim 1, characterized in that: In the copper electroplating step, the thickness of the electroplated copper ranges from 18um to 20um.

6. The method for manufacturing a slot electroplated copper plug for PCB to enhance heat dissipation according to claim 1, characterized in that: In the plugging step, the high temperature curing is performed at a temperature between 120° C. and 160° C., and the duration is between 1.5 h and 2.5 h.

7. The method for manufacturing a slot electroplated copper plug for PCB to enhance heat dissipation according to claim 1, characterized in that: After high temperature curing, the excess copper slurry is ground off using a ceramic grinding plate.

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