CN114727506A - Inner layer circuit board and manufacturing method thereof - Google Patents

Abstract

The application provides an inner layer circuit board and a manufacturing method thereof. The manufacturing method of the inner-layer circuit board comprises the steps of attaching the micro-adhesive film to the inner-layer copper plate to obtain an inner-layer film pasting plate; patterning the inner-layer film pasting plate to obtain an inner wire protection plate; and etching the inner wire protection plate, and removing the residual micro-adhesive film with a copper area on the inner wire protection plate to obtain the inner layer circuit board of the thick copper plate. Under the condition that the micro-adhesive film is used as a mask, the micro-adhesive film is tightly attached to the inner-layer copper plate, and the corresponding circuit pattern is formed after patterning, so that the leaked copper layer is conveniently etched and removed in the etching process, and the corresponding inner-layer circuit is formed on the inner-layer circuit board.

Description

Inner layer circuit board and manufacturing method thereof

Technical Field

The invention relates to the technical field of circuit boards, in particular to an inner-layer circuit board and a manufacturing method thereof.

Background

With the development of printed circuit board technology, more and more devices adopt printed circuit boards to perform integrated optimization on internal circuits, and besides small electronic devices, circuit miniaturization of large devices also becomes a demand. In the production of printed circuit boards, due to the design requirement of a power supply, the inner layer of a multilayer circuit board is required to be super-copper thick, and copper foil with the thickness exceeding 4oz is super-thick copper so as to meet the bearing requirement on large current.

However, in the process of manufacturing the inner layer circuit of the conventional thick copper plate, the dry film needs to be thickened under the condition of keeping the adhesion force, and the thickening can cause residue after development, which can easily cause poor development and thick spots generated during pattern copper electroplating; the dry film is thinned, so that the problems of poor development and thick spots are solved, the bonding force is poor, bubbles are easy to appear, and the yield of the thick copper plate is low.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides an inner-layer circuit board capable of effectively improving the probability of finished products and a manufacturing method thereof.

The purpose of the invention is realized by the following technical scheme:

a method for manufacturing an inner-layer circuit board comprises the following steps:

attaching the micro-adhesive film to the inner-layer copper plate to obtain an inner-layer film pasting plate;

patterning the inner-layer film pasting plate to obtain an inner wire protection plate;

and etching the inner wire protection plate, and removing the residual micro-adhesive film with a copper area on the inner wire protection plate to obtain the inner layer circuit board of the thick copper plate.

In one embodiment, the attaching the micro adhesive film to the inner copper plate includes: and pressing the micro-adhesive film on the inner-layer copper plate so as to enable the micro-adhesive film to be attached to the copper surface of the inner-layer copper plate.

In one embodiment, the peel strength of the micro-adhesive film is greater than or equal to 1 kgf/cm.

In one embodiment, the etching the inner wire protection plate includes: and carrying out wet etching on the internal wire protection plate to etch the copper layer except for the covering of the micro-adhesive film.

In one embodiment, the wet etching the inner wire protection plate includes: and carrying out flash etching on a copper leakage area on the inner wire protection plate.

In one embodiment, the thickness of the inner layer circuit board is 4OZ to 5 OZ.

In one embodiment, the attaching the micro-adhesive film to the inner copper plate to obtain the inner film pasting plate further comprises: and carrying out surface pretreatment on the inner-layer copper plate.

In one embodiment, the copper layer surface roughness of the inner copper plate is 0.2 μm to 0.3 μm.

In one embodiment, the micro-adhesive film comprises a pure adhesive layer and a covering layer which are arranged in a laminated mode, and the pure adhesive layer is bonded with the inner copper plate.

An inner-layer circuit board is manufactured by adopting the inner-layer circuit board manufacturing method in any embodiment.

Compared with the prior art, the invention has at least the following advantages:

under the condition that the micro-adhesive film is used as a mask, the micro-adhesive film is tightly attached to the inner-layer copper plate, and the corresponding circuit pattern is formed after patterning, so that the leaked copper layer is conveniently etched and removed in the etching process, and the corresponding inner-layer circuit is formed on the inner-layer circuit board.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

FIG. 1 is a flow chart of a method for fabricating an inner layer circuit board according to an embodiment;

fig. 2 to 4 are schematic structural diagrams corresponding to steps of the method for manufacturing the inner-layer circuit board shown in fig. 1.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

The invention relates to a method for manufacturing an inner-layer circuit board. In one embodiment, the method for manufacturing the inner-layer circuit board comprises the steps of attaching a micro-adhesive film to an inner-layer copper plate to obtain an inner-layer film pasting plate; patterning the inner-layer film pasting plate to obtain an inner wire protection plate; and etching the inner wire protection plate, and removing the residual micro-adhesive film with a copper area on the inner wire protection plate to obtain the inner layer circuit board of the thick copper plate. Under the condition that the micro-adhesive film is used as a mask, the micro-adhesive film is tightly attached to the inner-layer copper plate, and the corresponding circuit pattern is formed after patterning, so that the leaked copper layer is conveniently etched and removed in the etching process, and the corresponding inner-layer circuit is formed on the inner-layer circuit board.

Please refer to fig. 1, which is a flowchart illustrating a method for manufacturing an inner-layer circuit board according to an embodiment of the invention. The manufacturing method of the inner-layer circuit board comprises part or all of the following steps. Fig. 2 to fig. 4 are schematic structural diagrams corresponding to steps in a manufacturing method of an inner-layer circuit board according to an embodiment of the invention.

S100: and attaching the micro-adhesive film to the inner-layer copper plate to obtain the inner-layer film-attached plate.

In this embodiment, referring to fig. 2, the micro-adhesive film 100 is an adhesive cover film, and the micro-adhesive film 100 is used for bonding and connecting with the surface of the inner copper plate 200, that is, the micro-adhesive film 100 is bonded with the surface copper layer of the inner copper plate 200, so that the micro-adhesive film 100 is stably bonded on the inner copper plate 200. Moreover, the glass strength of the micro-adhesive film 100 is greater than 1kgf/cm, and the micro-adhesive film has a good adhesive bonding force, so that the surface bonding force between the micro-adhesive film 100 and the inner copper plate 200 is improved, the bonding effect between the micro-adhesive film 100 and the inner copper plate 200 is effectively improved, and the probability of air bubbles generated between the micro-adhesive film 100 and the inner copper plate 200 is effectively reduced.

S200: and patterning the inner-layer film pasting plate to obtain the inner wire protection plate.

In this embodiment, referring to fig. 3, the inner-layer film-laminated plate 300 is a film formed by the inner-layer copper plate 200 and the micro-adhesive film 100, that is, the micro-adhesive film 100 is tightly attached to the inner-layer copper plate 200, and the copper layer on the inner-layer film-laminated plate 300 is attached to the micro-adhesive film 100. In the process of patterning the inner-layer film-attached board 300, the micro-adhesive film 100 in the inner-layer film-attached board 300 is patterned, so that the micro-adhesive film 100 on the inner-layer copper board 200 forms a corresponding pattern, and the pattern corresponds to an inner-layer circuit required by an inner-layer circuit board. Thus, the micro adhesive film 100 is partially removed, so that a part of the copper layer on the inner copper plate 200 is exposed, and the other part of the copper layer is covered by the remaining micro adhesive film 100, thereby facilitating the subsequent etching of the exposed copper layer to manufacture the corresponding inner circuit.

S300: and etching the inner wire protection plate, and removing the residual micro-adhesive film with a copper area on the inner wire protection plate to obtain the inner layer circuit board of the thick copper plate.

In this embodiment, referring to fig. 4, the micro adhesive film 100 on the inner wire protection plate 400 has a pattern corresponding to the inner layer circuit 502, that is, the pattern of the micro adhesive film 100 on the inner wire protection plate 400 is the same as the pattern corresponding to the inner layer circuit 502, that is, the micro adhesive film 100 on the inner wire protection plate 400 covers the copper layer to be formed with the inner layer circuit 502. The internal wire protection plate 400 is provided with a bare copper area and a covered area, the covered area is an area covered by the micro-adhesive film 100, the bare copper area is an area outside the micro-adhesive film 100, a copper layer on the bare copper area is an action object of the etching treatment, and the copper layer etching is performed on the bare copper area of the internal wire protection plate 400 through the etching treatment of the internal wire protection plate 400, so that the area covered by the micro-adhesive film 100 is reserved, and the internal circuit 502 required by the internal circuit board 500 is formed conveniently. The thick copper plate is a multilayer core plate, and includes two layers of outer core plates and a plurality of layers of inner core plates, i.e., two layers of outer circuit boards and a plurality of layers of inner circuit boards 500.

In the above embodiment, under the condition that the micro-adhesive film 100 is used as a mask, the micro-adhesive film 100 is tightly attached to the inner-layer copper plate 200, and a corresponding circuit pattern is formed after patterning, so that the leaked copper layer can be conveniently removed by etching in the etching process, and the corresponding inner-layer circuit 502 is formed on the inner-layer circuit board 500, moreover, the use of the micro-adhesive film 100 omits development exposure, thereby effectively reducing the probability of residues on the inner-layer circuit 502, and further effectively improving the finished product probability of the inner-layer circuit board 500.

In one embodiment, the attaching the micro adhesive film 100 to the inner copper plate 200 includes: and pressing the micro-adhesive film 100 on the inner-layer copper plate 200 to make the micro-adhesive film 100 adhered to the copper surface of the inner-layer copper plate 200. In this embodiment, the micro-adhesive film 100 is adhesively bonded to the copper surface of the inner copper plate 200, and specifically, the peel strength of the micro-adhesive film 100 is 1kgf/cm or more. The micro-adhesive film 100 is pressed on the surface of the inner copper plate 200, so that the micro-adhesive film 100 is conveniently attached to the inner copper plate 200, the attaching force between the micro-adhesive film 100 and the copper layer surface of the inner copper plate 200 is improved, and the micro-adhesive film 100 is stably attached to the copper surface of the inner copper plate 200. Moreover, due to the strong adhesion force of the micro-adhesive film 100, the probability of air bubbles between the micro-adhesive film 100 and the surface of the inner copper plate 200 is reduced, and the probability of finished products of the inner circuit board 500 is effectively improved. In another embodiment, the micro-adhesive film 100 is attached to the copper layer surface of the inner copper plate 200 by cold pressing.

In one embodiment, the patterning process of the inner skin sheet 300 includes: the micro adhesive film 100 on the inner copper plate 200 is pattern cut so that the remaining micro adhesive film 100 corresponds to the inner wiring 502. In this embodiment, the micro-adhesive film 100 on the inner-layer copper plate 200 serves as a mask for the inner-layer circuit 502, and the pattern formed on the micro-adhesive film 100 corresponds to the inner-layer circuit 502. The pattern cutting of the micro adhesive film 100 on the inner copper plate 200 is to cut the micro adhesive film 100 on the inner copper plate 200 into a circuit pattern, so that after the pattern cutting process, the same circuit pattern as the inner circuit 502 is formed on the micro adhesive film 100 on the inner copper plate 200, so that the area covered by the remaining micro adhesive film 100 on the inner copper plate 200 corresponds to the inner circuit 502 area, and the area cut and removed on the inner copper plate 200 is used as a subsequent etching area, so that the copper layer in the area is subsequently etched and removed, thereby the copper layer corresponding to the inner circuit 502 is retained on the inner copper plate 200, and further, the required inner circuit 502 is subsequently formed on the inner copper plate 200.

Further, the pattern cutting process of the micro-adhesive film 100 on the inner copper plate 200 includes: the micro-adhesive film 100 on the inner copper plate 200 is laser cut to cut off the micro-adhesive film 100 outside the inner wiring 502. In this embodiment, the micro-adhesive film 100 on the inner copper plate 200 is a complete covering film before cutting, that is, the micro-adhesive film 100 completely covers the inner copper plate 200, that is, the micro-adhesive film 100 covers the copper layer on the inner copper plate 200. The micro-adhesive film 100 on the inner copper plate 200 is subjected to laser cutting, the micro-adhesive film 100 on the inner copper plate 200 is subjected to patterning treatment in a laser cutting processing mode, so that the micro-adhesive film 100 on the inner copper plate 200 is accurately cut, and the micro-adhesive film 100 pattern corresponding to the inner line 502 is obtained conveniently. Like this, under the high circumstances of the precision of laser cutting, the little mucosa 100 on the inner copper plate 200 is through the laser cutting back, the figure that remaining little mucosa 100 formed on the inner copper plate 200 corresponds each other with the figure of inlayer circuit 502, makes remaining little mucosa 100 on the inner copper plate 200 accurately covers on the inlayer circuit 502, thereby makes on the inlayer copper plate 200 by the regional alignment precision improvement of the region that little mucosa 100 covered and inlayer circuit 502.

In one embodiment, the etching process performed on the inner wire protection plate 400 includes: and performing wet etching on the inner wire protection plate 400 to etch a copper layer except for the covering of the micro adhesive film 100. In this embodiment, the inner wire protection plate 400 is the inner copper plate 200 after the micro-adhesive film 100 is subjected to the patterning process, at this time, the inner wire protection plate 400 is provided with the inner copper plate 200 and the remaining micro-adhesive film 100 after the patterning process, the area covered by the remaining micro-adhesive film 100 corresponds to the inner circuit 502, the area uncovered by the micro-adhesive film 100 is the bare copper area, and the copper layer corresponding to the bare copper area is the area to be removed by the wet etching. Thus, when the inner wire protection plate 400 is wet etched, the copper layer of the area, which is not covered by the micro-adhesive film 100, on the inner wire protection plate 400 is etched, so that the copper layer in the bare copper area is etched, the extra copper layer on the inner wire protection plate 400 is removed, the copper layer in the area covered by the micro-adhesive film 100 is retained, and the required inner layer circuit 502 is formed.

Further, the wet etching of the inner wire protection plate 400 includes: and performing flash etching on the copper leakage area on the inner wire protection plate 400. In this embodiment, the flash etching is a wet etching method, and the flash etching rapidly etches away the residual copper in the non-pattern area without etching too much copper in the pattern area, so as to increase the longitudinal etching amount, reduce the lateral etching amount, and effectively maintain the profile of the inner layer circuit 502. The flash etching is to etch the copper layer in the area, which is not covered by the micro-adhesive film 100, on the inner wire protection plate 400, and the copper layer in the area other than the inner layer circuit 502 is etched, so that the copper layer in the copper leakage area on the inner wire protection plate 400 is removed, and the linear profile of the copper layer in the area covered by the micro-adhesive film 100 can be ensured, thereby effectively improving the linear accuracy of the inner layer circuit 502. In addition, in order to manufacture a multi-layer thick copper plate, the thickness of the inner-layer circuit 502 needs to be kept relatively thin, specifically, the thickness of the inner-layer circuit 502 is 4OZ to 5OZ, and the inner-layer circuit 502 does not need to be subjected to patterning operation to be thickened, and only needs to be etched on the original copper plate.

Still further, the flash etching is performed on the copper leakage area on the inner wire protection plate 400, and then the method further includes: and removing the residual micro-adhesive film 100 with the copper area on the inner wire protection plate 400. In this embodiment, after the copper leakage area on the inner wire protection plate 400 is flash-etched, the copper layer corresponding to the coverage area of the micro adhesive film 100 on the inner wire protection plate 400 is the inner circuit 502, and at this time, the remaining micro adhesive film 100 on the inner wire protection plate 400 is torn off, so that the inner circuit 502 can be exposed, thereby facilitating the formation of the inner circuit board 500 of the thick copper plate.

In one embodiment, the attaching of the micro-adhesive film 100 to the inner copper plate 200 to obtain the inner film pasting board 300 further includes: the inner copper plate 200 is subjected to surface pretreatment. In this embodiment, the copper layer on the inner copper plate 200 is used for bonding to the micro-adhesive film 100, and the bonding force between the micro-adhesive film 100 and the inner copper plate 200 is affected by the surface roughness of the copper layer in addition to the viscosity of the micro-adhesive film 100 itself. The surface pretreatment of the inner copper plate 200 is to roughen the surface of the copper layer of the inner copper plate 200 so as to increase the adhesion force between the micro-adhesive film 100 and the inner copper plate 200. After the surface pretreatment of the inner-layer copper plate 200, the roughness of the copper layer of the inner-layer copper plate 200 is 0.2 μm to 0.3 μm, which effectively improves the bonding force between the micro-adhesive film 100 and the inner-layer copper plate 200, so that the micro-adhesive film 100 is more closely bonded to the inner-layer copper plate 200, and the probability of forming bubbles between the micro-adhesive film 100 and the inner-layer copper plate 200 is effectively reduced.

In one embodiment, the micro-adhesive film 100 includes a pure adhesive layer and a cover layer, which are stacked and bonded to the inner copper plate 200. In this embodiment, the material of pure glue layer is the epoxy adhesive, the overburden includes film sublayer and epoxy adhesive sublayer, pure glue layer be used for with the copper layer surface bonding of inlayer copper 200, pure glue layer deviates from one side of inlayer copper 200 is connected with the epoxy adhesive sublayer of overburden, the overburden passes through epoxy adhesive sublayer with pure glue layer bonds, and the film sublayer is located the outside of overburden is as the mask protection layer in the flash etching operation, is convenient for form corresponding inlayer circuit 502 pattern.

It can be understood that, in the process of performing flash etching on the inner wire protection plate 400, flash etching liquid medicine etches the residual micro-adhesive film 100 on the inner wire protection plate 400 and the previous joint position of the copper plate, that is, the flash etching liquid medicine basically vertically etches along the edge of the residual micro-adhesive film 100 on the inner wire protection plate 400, so as to ensure the longitudinal etching amount and reduce the transverse etching amount, so that the edge profile of the inner layer circuit 502 formed after flash etching is neat, and the line width of the flash etched inner layer circuit 502 meets the requirement.

In the process of laser cutting the micro-adhesive film 100 on the inner copper plate 200, the laser cutting machine irradiates the cut material with a high-power-density laser beam, so that the material is heated to a vaporization temperature quickly, holes are formed by vaporization, slits with a narrow width are continuously formed in the holes along with the movement of the material by the laser beam, the material of the micro-adhesive film 100 is different from the copper layer greatly, particularly, the difference in thermal deformation is obvious, that is, when the micro-adhesive film 100 is cut by the laser beam, the temperature of the micro-adhesive film 100 at the cutting position rises sharply, although the time is short, the micro-adhesive film 100 at the cutting position is enough to be separated from the copper layer due to thermal expansion, so that the copper plate corresponding to the edge of the micro-adhesive film 100 is subjected to over-etching by a flash etching liquid medicine in the subsequent flash etching process, therefore, the line width of the formed inner layer circuit 502 is easily unqualified, and finally the inner layer circuit board 500 is directly scrapped.

In order to reduce the probability of the inner circuit board 500 being scrapped due to insufficient line width, the method performs laser cutting on the micro-adhesive film 100 on the inner copper plate 200 to cut off the micro-adhesive film 100 outside the inner circuit 502, and then further comprises the following steps:

acquiring a transverse cutting image of the inner wire protection plate 400;

acquiring a single-line bonding distance according to the transverse cutting image;

detecting whether the single-wire bonding distance is smaller than a preset distance;

and when the single-wire bonding distance is smaller than the preset distance, sending a first alarm signal to a line monitoring system.

In this embodiment, in the process of manufacturing the inner-layer circuit board 500, the circuit board production system further includes a corresponding image acquisition module and a corresponding processing module, the image acquisition module is configured to acquire images of the circuit board in all directions during the production process, so as to ensure that each process of the production of the circuit board is monitored, and the processing module correspondingly performs data processing on the acquired images, so as to timely send out an early warning to the circuit monitoring system. The image acquisition module is used for acquiring transverse images of the internal wire protection plate 400 after the inner-layer copper plate 200 is subjected to laser cutting treatment on the micro-adhesive film 100, so as to obtain transverse cutting images of the internal wire protection plate 400, wherein the transverse cutting images correspond to images of all levels of structures of the internal wire protection plate 400, and the transverse cutting images comprise stacked images of all levels of the substrate, the copper plate and the micro-adhesive film 100. Acquiring a single-line bonding distance according to the transverse cutting image, wherein the contact area between the micro-adhesive film 100 and the copper plate in the transverse cutting image is acquired, so that the contact length between the micro-adhesive film 100 and the copper plate after laser cutting is convenient to determine, and the single-line bonding distance is the length seen along the routing direction of the pattern corresponding to the inner layer circuit 502, namely the single-line bonding distance is the single-line width of the residual micro-adhesive film 100. Since the micro adhesive film 100 on the inner wire protection plate 400 is used to cover the copper layer where the inner layer circuit 502 is located, the single wire bonding distance is used to embody an effective covering width between the micro adhesive film 100 and the inner wire protection plate 400. The preset distance is the standard line width corresponding to the inner-layer circuit board 500, that is, the preset distance is the line width required by the inner-layer circuit board 500, and the single-wire bonding distance is smaller than the preset distance, which indicates that the contact width between the residual micro-adhesive film 100 on the inner wire protection board 400 and the copper plate is too short at this time, that is, the situation that the residual micro-adhesive film 100 on the inner wire protection board 400 and the copper plate are excessively degummed at the edge is indicated, which easily causes excessive etching of the copper plate on the inner wire protection board 400 in the subsequent flash etching process, thereby easily causing the formed unqualified width of the inner-layer circuit 502. Like this, send first alarm signal to circuit monitoring system this moment, wherein, not only have early warning signal among the first alarm signal, still include single line bonding distance isoparametric, so that circuit monitoring system knows the handling condition of circuit board in real time, still is convenient for stop subsequent erosion by flash operation under the current situation simultaneously, in order to reduce inlayer circuit board 500 is because of the condemned probability of linewidth not enough.

Further, in the process of measuring the single-wire bonding distance, only the horizontal attaching distance is calculated, that is, the line width of the inner layer circuit 502 to be formed is determined in the lateral direction. The micro-adhesive film 100 and the copper plate are in edge degumming condition, and the edge is easy to warp, before the subsequent flash etching process, the upwarp part of the micro-adhesive film 100 is partially recovered, so that the contact width of the micro-adhesive film 100 and the copper plate is increased, the finally formed inner layer circuit 502 is too wide, and the unqualified inner layer circuit board 500 is also caused.

In order to solve the above problem, the method for detecting whether the single wire bonding distance is smaller than a preset distance further comprises the following steps:

when the single-line bonding distance is larger than or equal to the preset distance, obtaining an edge warping height according to the transverse cutting image;

detecting whether the edge warping height is larger than a preset height or not;

and when the edge warping height is greater than the preset height, sending a second alarm signal to the line monitoring system.

In this embodiment, the single wire bonding distance is greater than or equal to the preset distance, which indicates that the contact width between the remaining micro-adhesive film 100 on the internal wire protection plate 400 and the copper plate meets the requirement, i.e., that the degum between the remaining micro-adhesive film 100 on the internal wire protection plate 400 and the copper plate occurs at the edge is normal, i.e., that the line width of the copper layer covered by the micro-adhesive film 100 is equivalent to the line width of the internal layer circuit 502 at this time. At this time, since the remaining micro-adhesive film 100 on the inner wire protection plate 400 and the copper plate are deglued at the edge, the edge of the remaining micro-adhesive film 100 on the inner wire protection plate 400 is warped upwards. The edge warping height is obtained according to the transverse cutting image, that is, the edge warping degree of the micro-adhesive film 100 is obtained on the transverse surface of the inner wire protection plate 400, so that the distance between the two sides of the residual micro-adhesive film 100 on the inner wire protection plate 400 and the copper plate can be conveniently determined. The preset height is the maximum allowable upwarping height of the micro adhesive film 100 on the inner wire protection plate 400, that is, at the preset height, the line width of the inner layer circuit 502 is not expanded even if the remaining micro adhesive film 100 on the inner wire protection plate 400 is recovered. The edge warping height is greater than the preset height, which indicates that after the remaining micro-adhesive film 100 on the internal wire protection plate 400 recovers, the micro-adhesive film 100 excessively increases the contact length between the micro-adhesive film 100 and the copper plate, so that the line width of the finally formed internal layer circuit 502 is excessively large. Like this, this moment to circuit monitoring system sends second alarm signal, contain in the second alarm signal edge warpage height and single line bonding distance, the monitoring personnel of being convenient for in time know interior line protection board 400's little mucosa 100 covers and upwarp the condition to be convenient for in time stop subsequent flash corrosion operation, with the disqualification probability that reduces inlayer circuit board 500.

Still further, although the edge warp height may avoid the situation that the inner layer line 502 is too wide, under the qualified upwarp height, the situation that the flash etching liquid medicine is excessively contacted still exists, which may easily cause the line profile formed by the flash etching to be abnormal, specifically, the excessive flash etching liquid medicine enters the warp position to cause the edge of the inner layer line 502 to present an inverse trapezoid structure, that is, in the direction close to the substrate, the line width of the inner layer line 502 is gradually reduced.

In order to ensure that the line width of the inner layer line 502 is stable, the method for detecting whether the edge warp height is greater than a preset height further includes the following steps:

when the edge warping height is smaller than or equal to the preset height, obtaining the edge warping extension degree according to the transverse cutting image;

performing edge degree processing on the edge warping extension degree and the edge warping height to obtain an edge warping angle;

detecting whether the edge warping angle is smaller than a preset angle or not;

and when the edge warping angle is smaller than the preset angle, sending a third alarm signal to the line monitoring system.

In this embodiment, the edge warpage height is less than or equal to the preset height, which indicates that after the remaining micro-adhesive film 100 on the internal wire protection plate 400 is recovered, the micro-adhesive film 100 increases the contact length between the micro-adhesive film 100 and the copper plate within an allowable range, so that the overall line width of the finally formed internal layer circuit 502 meets the requirement. The flash etching liquid medicine as a liquid can invade to the degumming position between the micro-mucosa 100 and the copper plate, namely the upwarp position of the micro-mucosa 100, and the upwarp degree of the micro-mucosa 100 directly influences the trend of the flash etching liquid medicine. Acquiring an edge warping extension according to the transverse cutting image, acquiring the edge warping length of the micro-adhesive film 100, and then performing edge processing on the edge warping extension and the edge warping height, wherein the edge warping extension and the edge warping height are correspondingly converted into a warping angle of the edge of the micro-adhesive film 100 on the copper plate, namely the edge warping angle. Wherein the preset angle is set according to a profile required by the inner layer circuit 502, specifically, the preset angle is 90 °. The edge warping angle is smaller than the preset angle, which indicates that the upwarping angle of the edge of the micro-adhesive film 100 on the copper plate is smaller than 90 degrees, namely that the edge of the micro-adhesive film 100 and the copper plate are in an inclined state rather than a vertical state. Like this, in the follow-up flash etching process, flash etching liquid medicine will the distribution at the edge of little mucosa 100 is the tilt state for the excessive sculpture of lower part on copper layer, at this moment to circuit monitoring system sends third alarm signal, contain marginal warpage angle, marginal warpage height and single line bonding distance among the third alarm signal, be convenient for in time know the condition that the profile deformation can appear in inlayer circuit 502, thereby be convenient for in time stop subsequent flash etching operation, in order to ensure that inlayer circuit 502 appears the probability reduction of profile deformation, further improved inlayer circuit board 500's qualification probability.

In one embodiment, the present application further provides an inner-layer circuit board manufactured by the inner-layer circuit board manufacturing method according to any one of the above embodiments. In this embodiment, the method for manufacturing the inner-layer circuit board includes attaching a micro-adhesive film to an inner-layer copper plate to obtain an inner-layer film-attached plate; patterning the inner-layer film pasting plate to obtain an inner wire protection plate; and etching the internal line protection plate, and removing the residual micro-adhesive film with the copper area on the internal line protection plate to obtain the inner layer circuit board of the thick copper plate. Under the condition that the micro-adhesive film is used as a mask, the micro-adhesive film is tightly attached to the inner-layer copper plate, and the corresponding circuit pattern is formed after patterning, so that the leaked copper layer is conveniently etched and removed in the etching process, and the corresponding inner-layer circuit is formed on the inner-layer circuit board.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that various changes and modifications can be made by those skilled in the art without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. A manufacturing method of an inner layer circuit board is characterized by comprising the following steps:

attaching the micro-adhesive film to the inner-layer copper plate to obtain an inner-layer film pasting plate;

patterning the inner-layer film pasting plate to obtain an inner wire protection plate;

and etching the inner wire protection plate, and removing the residual micro-adhesive film with a copper area on the inner wire protection plate to obtain the inner layer circuit board of the thick copper plate.

2. The method for manufacturing an inner-layer circuit board according to claim 1, wherein the step of attaching the micro-adhesive film to the inner-layer copper plate comprises:

and pressing the micro-adhesive film on the inner-layer copper plate so as to enable the micro-adhesive film to be attached to the copper surface of the inner-layer copper plate.

3. The method of manufacturing an inner layer wiring board according to claim 1, wherein the peel strength of the micro-adhesive film is 1kgf/cm or more.

4. The method for manufacturing an inner wiring board according to claim 1, wherein the etching the inner wiring protection board includes:

and carrying out wet etching on the internal wire protection plate to etch the copper layer except for the covering of the micro-adhesive film.

5. The method for manufacturing an inner wiring board according to claim 4, wherein the wet etching the inner wiring protection board includes:

and carrying out flash etching on a copper leakage area on the inner wire protection plate.

6. The method for manufacturing an inner-layer circuit board according to claim 1, wherein the thickness of the inner-layer circuit board is 4OZ to 5 OZ.

7. The method for manufacturing an inner-layer circuit board according to claim 1, wherein the micro-adhesive film is attached to the inner-layer copper plate to obtain an inner-layer film-attached plate, and the method further comprises the following steps:

and carrying out surface pretreatment on the inner-layer copper plate.

8. The method of manufacturing an inner layer wiring board according to claim 1, wherein the surface roughness of the copper layer of the inner layer copper plate is 0.2 μm to 0.3 μm.

9. The method for manufacturing an inner-layer circuit board according to claim 1, wherein the micro-adhesive film comprises a pure adhesive layer and a covering layer which are laminated, and the pure adhesive layer is bonded with the inner-layer copper plate.

10. An inner layer wiring board produced by the method for producing an inner layer wiring board according to any one of claims 1 to 9.

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