Circuit board embedded copper block manufacturing method

Abstract

The invention relates to the technical field of circuit board manufacturing, and particularly discloses a circuit board embedded copper block manufacturing method which comprises the following steps: milling a mother board so as to form an embedded copper groove on the mother board, the size of the embedded copper groove is larger than that of a copper block, and milling a plurality of lug bosses at intervals along the circumferential direction on the side wall of the embedded copper groove; a high-temperature adhesive tape is attached to one side of the mother board, so that the high-temperature adhesive tape blocks the groove opening of the copper burying groove; the copper block is placed in the copper burying groove, and the copper block is positioned through a plurality of protruding parts; and vacuum resin filling treatment is carried out on a gap between the groove wall of the copper burying groove and the copper block. According to the manufacturing method of the circuit board embedded copper block, the flatness of the copper block on the mother board can be improved, the copper block is prevented from deviating, the phenomenon that the subsequent production process is affected due to the poor adhesive residue after the copper block position is pressed is avoided, meanwhile, the embedded copper groove and the protruding part are formed through a one-time process, and therefore occupation of a circuit board routing machine is reduced, the productivity is released, and the production efficiency is improved. And the productivity pressure is relieved.

Description

Technical Field

[0001] The invention relates to the technical field of circuit board manufacturing, and in particular to a method for manufacturing a buried copper block of a circuit board. Background Art

[0002] With the continuous development of electronic communication technology, electronic devices have more and more functions, resulting in a denser layout of circuit board devices and a continuous increase in the number of layers. In order to prevent the circuit board from overheating and damage and ensure stable operation, it is necessary to improve the heat dissipation performance of the circuit board. At present, copper blocks can be buried in the circuit board manufacturing process. By utilizing the high thermal conductivity and low resistivity of copper, the heat generated by electronic components is absorbed and dispersed, keeping the circuit board within the normal temperature range, thereby improving the overall heat dissipation efficiency.

[0003] In the prior art, the buried copper block process involves milling an inner groove at the location where the copper block is placed on the inner layer sub-board, and pressing the copper block and the inner layer sub-board together to form a multi-layer circuit board. During the pressing process, the semi-cured film will flow and solidify, so that the layers are bonded together. However, during this process, the copper block is prone to uneven placement when stacking the boards, and residual glue will form at the location of the copper block after pressing, affecting subsequent production processes. Summary of the invention

[0004] The purpose of the present invention is to provide a method for manufacturing buried copper blocks of circuit boards to solve the problem in the prior art that copper blocks are prone to uneven placement when stacking boards, and residual glue will form at the position of the copper blocks after pressing, affecting subsequent production processes.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for manufacturing a buried copper block of a circuit board, comprising the following steps:

[0007] The motherboard is subjected to a milling process to form a copper-embedded groove on the motherboard, wherein the size of the copper-embedded groove is larger than the size of the copper block, and a plurality of convex portions spaced apart along the circumferential direction are milled on the side wall of the copper-embedded groove;

[0008] Affixing a high temperature tape to one side of the motherboard so that the high temperature tape seals the notch of the copper embedding groove;

[0009] Placing the copper block in the copper embedding groove and positioning the copper block by using a plurality of the protruding parts;

[0010] The gap between the buried copper groove wall and the copper block is vacuum plugged with resin.

[0011] As an optional solution of the method for manufacturing the buried copper block of the circuit board, the spacing distance between the copper block and the wall of the buried copper groove is 6 mil to 10 mil.

[0012] As an optional solution of the method for manufacturing the buried copper block of the circuit board, the protrusion is an arc-shaped structure, and the maximum distance between the protrusion and the wall of the buried copper groove is 4 mil.

[0013] As an optional scheme for the above-mentioned method for manufacturing buried copper blocks of circuit boards, the vacuum plugging resin treatment of the gap between the buried copper groove and the copper block includes: performing a first vacuum plugging resin treatment on the gap between the buried copper groove wall and the copper block through a first screen, and then performing a second vacuum plugging resin treatment on the gap between the buried copper groove wall and the copper block through a second screen, wherein the connecting ribs between the first screen and the second screen are staggered.

[0014] As an optional scheme for the above-mentioned method for making buried copper blocks of circuit boards, after the first screen is used to perform the first vacuum plug resin treatment and before the second screen is used to perform the second vacuum plug resin treatment, it also includes: first baking the resin and then coarse grinding the resin.

[0015] As an optional solution of the method for manufacturing the buried copper block of the circuit board, the first baking of the resin includes: baking the resin between the wall of the buried copper groove and the copper block on a cassette rack.

[0016] As an optional solution of the method for manufacturing buried copper blocks of the circuit board, after the resin is baked for the first time and before the resin is roughly ground, the method further includes: removing the high-temperature tape.

[0017] As an optional solution of the method for manufacturing buried copper blocks of the above circuit board, after the second vacuum plugging resin treatment is performed through the second screen, it also includes: baking the resin for a second time and then fine grinding the resin.

[0018] As an optional solution of the method for manufacturing buried copper blocks of the circuit board, after fine grinding the resin, it also includes: performing plug hole AOI inspection on the wall of the buried copper groove and the copper block.

[0019] As an optional scheme for the above-mentioned method of manufacturing buried copper blocks of circuit boards, before the motherboard is subjected to milling treatment to form buried through grooves on the motherboard, it also includes: cutting, image transfer, AOI inspection and browning treatment of the inner layer sub-boards in sequence, and then forming the motherboard by pressing the motherboards together, and drilling and electroplating the motherboards in sequence.

[0020] The beneficial effects of the present invention are:

[0021] First, the motherboard is milled to form a copper-buried groove for embedding copper blocks on the motherboard, and the size of the copper-buried groove is larger than the size of the copper block. At the same time, in the process of forming the copper-buried groove, a number of convex parts spaced along the circumferential direction are directly left on the side wall of the copper-buried groove by milling, so that when the copper block is placed in the copper-buried groove, the several convex parts can hold the copper block in place, thereby preventing the copper block from being displaced. Among them, high-temperature tape is attached to one side of the motherboard, so that when the copper block is placed in the copper-buried groove, the flatness of the copper block relative to the motherboard can be improved, and then the gap between the wall of the copper-buried groove and the copper block is vacuum plugged with resin, so that the copper block is bonded and fixed to the motherboard. The method for making buried copper blocks of circuit boards can improve the flatness of copper blocks on the motherboard, prevent the copper blocks from being displaced, and avoid the phenomenon of residual glue after the copper block position is pressed, which affects the subsequent production process. At the same time, the buried copper groove and the convex parts are formed in one process, thereby reducing the occupation of the circuit board gong machine, releasing production capacity, and alleviating production capacity pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a process for manufacturing a buried copper block of a circuit board provided by an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of the structure of a buried copper block of a circuit board provided by an embodiment of the present invention;

[0024] Figure 3 A schematic structural diagram of a buried copper block of a circuit board provided by an embodiment of the present invention from another perspective.

[0025] In the figure:

[0026] 1. Motherboard; 11. Copper buried groove; 111. Raised part; 2. Copper block; 3. High temperature tape. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] In the description of the present invention, 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 the present invention can be understood according to specific circumstances.

[0030] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0031] like Figure 1 to Figure 3 As shown, this embodiment provides a method for manufacturing a buried copper block of a circuit board, comprising the following steps:

[0032] The motherboard 1 is subjected to a milling process to form a copper-embedded groove 11 on the motherboard 1, and the size of the copper-embedded groove 11 is larger than the size of the copper block 2, and a plurality of convex portions 111 spaced apart in the circumferential direction are milled out on the side wall of the copper-embedded groove 11;

[0033] A high temperature adhesive tape 3 is attached to one side of the motherboard 1 so that the high temperature adhesive tape 3 seals the notch of the buried copper groove 11;

[0034] The copper block 2 is placed in the copper embedding groove 11, and the copper block 2 is positioned by a plurality of protrusions 111;

[0035] The gap between the wall of the buried copper groove 11 and the copper block 2 is vacuum plugged with resin.

[0036] The present embodiment provides a method for manufacturing buried copper blocks of a circuit board. In the circuit board manufacturing process, the motherboard 1 is first milled to form a buried copper groove 11 for embedding the copper block 2 on the motherboard 1, and the size of the buried copper groove 11 is larger than the size of the copper block 2. At the same time, in the process of forming the buried copper groove 11, a plurality of circumferentially spaced protrusions 111 are directly reserved on the side wall of the buried copper groove 11 by milling, so that when the copper block 2 is placed in the buried copper groove 11, the plurality of protrusions 111 can hold the copper block 2 in place, thereby preventing the copper block 2 from being displaced. A high-temperature tape 3 is attached to one side of the motherboard 1, so that when the copper block 2 is placed in the buried copper groove 11, the flatness of the copper block 2 relative to the motherboard 1 can be improved. Then, the gap between the wall of the buried copper groove 11 and the copper block 2 is vacuum plugged with resin, so that the copper block 2 is bonded and fixed to the motherboard 1.

[0037] The method for manufacturing buried copper blocks for circuit boards can improve the flatness of the copper block 2 on the motherboard 1, prevent the copper block 2 from being offset, and avoid the phenomenon of residual glue after the copper block 2 is pressed into position, which affects the subsequent production process. At the same time, the buried copper groove 11 and the raised portion 111 are formed in a one-time process, thereby reducing the occupancy of the circuit board gong machine, releasing production capacity, and alleviating production capacity pressure.

[0038] Furthermore, before the motherboard 1 is subjected to milling treatment to form buried through grooves on the motherboard 1, the inner-layer sub-boards are cut, transferred, AOI inspected and browned in sequence. Several inner-layer sub-boards are then pressed together through the motherboard 1 to form the motherboard 1, and the motherboard 1 is drilled and electroplated in sequence. This process can directly form a pressed motherboard 1 with a stable overall structure, which is convenient for opening buried copper grooves 11, and the thickness of the copper block 2 can be used according to the thickness of the motherboard 1, so as to facilitate the control of the overall flatness, so that the flatness can be controlled within ±1mil.

[0039] Specifically, the spacing distance between the copper block 2 and the wall of the buried copper groove 11 is 6mil to 10mil, so that there is a certain distance between the copper block 2 and the wall of the buried copper groove 11, so as to facilitate the vacuum plugging of the resin. At the same time, the protrusion 111 is an arc-shaped structure, and the maximum distance between the protrusion 111 and the wall of the buried copper groove 11 is 4mil, so that there is a small gap between the protrusion 111 and the copper block 2, which can realize the flow of resin, and the protrusion 111 of the arc-shaped structure has an arc-shaped surface, and the setting of the arc-shaped surface can reduce the difficulty of resin flow and prevent resin clogging.

[0040] Furthermore, vacuum plug resin treatment is performed on the gap between the buried copper groove 11 and the copper block 2, including performing a first vacuum plug resin treatment on the gap between the groove wall of the buried copper groove 11 and the copper block 2 through a first screen, and then performing a second vacuum plug resin treatment on the gap between the groove wall of the buried copper groove 11 and the copper block 2 through a second screen, wherein the connecting ribs of the first screen and the second screen are staggered, so that the copper block 2 can be bonded to the motherboard 1 by performing the first vacuum plug resin treatment by the first screen, and then the second vacuum plug resin treatment is performed by the second screen to fill the gap, thereby preventing resin leakage due to the obstruction of the connecting ribs of the first screen.

[0041] Specifically, after the first vacuum plug resin treatment is performed through the first screen, and before the second vacuum plug resin treatment is performed through the second screen, the resin is also baked for the first time, and then the resin is roughly ground. The first baking can remove moisture in the resin to prevent bubbles from affecting product quality. At the same time, it can also promote the curing of the resin and improve efficiency. The resin is then roughly ground so that the resin can be flat and convenient for subsequent processes. Among them, the first baking of the resin includes baking the resin between the groove wall of the buried copper groove 11 and the copper block 2 on the lycra rack. This process can prevent the copper block 2 from moving, thereby avoiding flatness problems. At the same time, after the resin is baked for the first time and before the resin is roughly ground, it also includes taking out the high-temperature tape 3. After the resin is baked for the first time, the copper block 2 is fixed to the motherboard 1 by the resin. At this time, the high-temperature tape 3 is taken out to facilitate subsequent processes.

[0042] Furthermore, after the second vacuum plugging resin treatment is performed by the second screen, the resin is baked for the second time, and then the resin is finely ground. The second baking can remove the moisture in the newly added resin to prevent the generation of bubbles that affect the product quality. The resin is then finely ground to perform surface treatment on the motherboard 1 to improve the flatness. After the resin is finely ground, the plugging hole AOI detection is also performed between the groove wall of the buried copper groove 11 and the copper block 2. The plugging hole AOI detection is used to determine whether there are defects, thereby reducing the generation of defective products.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for manufacturing a buried copper block of a circuit board, characterized in that: The following steps are involved: The motherboard is subjected to a milling process to form a copper-embedded groove on the motherboard, wherein the size of the copper-embedded groove is larger than the size of the copper block, and a plurality of convex portions spaced apart along the circumferential direction are milled on the side wall of the copper-embedded groove; Affixing a high temperature tape to one side of the motherboard so that the high temperature tape seals the notch of the copper embedding groove; Placing the copper block in the copper embedding groove and positioning the copper block by using a plurality of the protruding parts; The gap between the buried copper groove wall and the copper block is vacuum plugged with resin.

2. The method for manufacturing a buried copper block of a circuit board according to claim 1, characterized in that: The distance between the copper block and the wall of the buried copper groove is 6 mil to 10 mil.

3. The method for manufacturing a buried copper block of a circuit board according to claim 2, characterized in that: The protrusion is an arc-shaped structure, and the maximum distance between the protrusion and the wall of the buried copper groove is 4 mil.

4. The method for manufacturing a buried copper block of a circuit board according to claim 1, characterized in that: The vacuum plugging resin treatment of the gap between the buried copper groove and the copper block includes: performing a first vacuum plugging resin treatment on the gap between the buried copper groove wall and the copper block through a first screen, and then performing a second vacuum plugging resin treatment on the gap between the buried copper groove wall and the copper block through a second screen, wherein the connecting ribs between the first screen and the second screen are staggered.

5. The method for manufacturing a buried copper block of a circuit board according to claim 4, characterized in that: After the first vacuum plug resin treatment is performed by the first screen and before the second vacuum plug resin treatment is performed by the second screen, the method further includes: first baking the resin and then coarse grinding the resin.

6. The method for manufacturing a buried copper block of a circuit board according to claim 5, characterized in that: The first baking of the resin includes: baking the resin between the wall of the buried copper groove and the copper block on a cassette rack.

7. The method for manufacturing a buried copper block of a circuit board according to claim 5, characterized in that: After the resin is baked for the first time and before the resin is roughly ground, the method further includes: taking out the high temperature tape.

8. The method for manufacturing a buried copper block of a circuit board according to claim 4, characterized in that: After the second vacuum plugging resin treatment is performed through the second screen, the method also includes: baking the resin for a second time and then fine grinding the resin.

9. The method for manufacturing a buried copper block of a circuit board according to claim 8, characterized in that: After fine grinding the resin, the method further includes: performing plug hole AOI inspection on the wall of the buried copper groove and the copper block.

10. The method for manufacturing a buried copper block of a circuit board according to any one of claims 1 to 9, characterized in that: The method of milling the motherboard to form buried through grooves on the motherboard also includes: cutting, image transfer, AOI inspection and browning of the inner layer sub-boards in sequence, and then forming the motherboard by pressing the motherboards, and drilling and electroplating the motherboards in sequence.

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