KR100656416B1 - The thick copper pcb and method to printed circuit board - Google Patents

Abstract

A thick copper printed circuit board(PCB) and a method for manufacturing the same are provided to reduce a manufacturing cost and time, and improve reliability of a PCB by filling and drying a filler into a circuit gap and forming a second circuit where a copper plating is performed after drilling a penetration hole. A method for manufacturing a thick copper PCB includes the steps of: manufacturing a substrate(30) by inserting and compressing an insulation layer(20) between a copper thin film(10); perforating a plurality of guide holes on four corners of the copper thin film(10) and the insulation layer(20); eroding a first circuit GAP on the copper thin film(10) which forms an upper/lower part of the substrate(30); filling a filler(50) into the first circuit GAP of the copper thin film(10); performing a planarization of a surface of the copper thin film(10) which the filler(50) is filled into the first circuit GAP; forming a hole(60) which penetrates an upper/lower part of the substrate(30); forming a plating layer which plates the penetration hole(60) and the upper/lower part of the substrate(30); forming a second circuit which erodes a second circuit GAP on an upper part of the plating layer; and processing a surface of the plated substrate and processing an outer shape.

Description

The thick copper pcb and method to printed circuit board

1 is a view showing the first to third steps in the manufacturing process of the present invention,

2 is a view showing the fourth to sixth steps in the manufacturing process of the present invention,

3 is a view showing the seventh step to the eighth step of the manufacturing process of the present invention.

<Brief description of the major symbols in the drawing shown>

10; Copper foil 20; Insulation layer

30; Substrate 40; Primary Circuit GAP

50; Filler 60; hall

70; Plating layer 80; Secondary circuit GAP

The present invention relates to a method for manufacturing a multi-ply printed circuit board and a substrate thereof. In particular, a filler is filled into a circuit gap formed primarily, pre-drying, main drying, and flattening are processed, and a hole to be conductive is used, and copper plating is applied to the entire substrate. Then, the present invention relates to a method for manufacturing a thick copper PCB and a PCB which can eliminate soldering defects due to the filler remaining in the through hole by manufacturing the circuit in a second step.

Generally, it is used as the most basic component of many electronic products currently manufactured.

In recent years, PCBs for higher current energization have been widely used in PCBs for automotive power, industrial equipment power, display power such as LCD and PDP, LED module, IPM, SPM, HDI and so on.

Therefore, since the PCB is required to be lighter, thinner, and higher current, there is a need for a multi-ply PCB.

However, the conventional multi-layer PCB manufacturing method has many problems.

It is common to use a method of first forming a through hole and then corroding the circuit gap and then filling the gap with a filler.

However, this method has a problem in that defects that remain in the conductive hole wall in which the filler is formed and are not soldered when soldering parts are generated.

The present invention, which solves the above problems, relates to a manufacturing method of a multi-layer printed circuit board and a substrate thereof. In particular, the conductive hole is filled with a filler and cured in a primary circuit, and then drilled through the through hole after flattening. The purpose of the present invention is to provide a method for manufacturing a thick copper PCB and a PCB for removing a defect of filler in a through hole by copper plating and forming a secondary circuit.
Accordingly, the present invention provides a method of manufacturing a THICK COPPER PCB printed circuit board, comprising the steps of: preparing a substrate by sandwiching an insulating layer between copper foils, and thermally compressing and integrating the insulating layer; Second step: drilling a plurality of guide holes in each of four corners of the substrate of the integrated copper thin film and the insulating layer; A third step of forming a primary circuit GAP in a shape of a circuit in the copper thin film forming upper and lower substrates; Step 4: filling and drying the filler in the primary circuit GAP of the copper thin film; Step 5: flattening the surface of the copper thin film filled with the filler in the primary circuit GAP; Step 6: drilling a hole penetrating the upper and lower sides of the substrate; Step 7: forming a plating layer by plating the upper and lower portions of the upper and lower portions of the substrate and the upper and lower portions of the substrate on the entire surface; Eighth step: forming a secondary circuit to form a secondary circuit GAP on the plating layer; The ninth step is to process the surface of the plated substrate, and to process the appearance to provide a thick copper PCB manufacturing method for forming a printed circuit board.

delete

In addition, the insulating layer used in the first step of the present invention, epoxy, aramid or polyimide material is optionally used; The filler of the fourth step is to provide a method of manufacturing a thick copper PCB substrate using a epoxy, polyimide, aramid, general resin, or a heat dissipation resin to selectively produce a substrate.

In addition, after the filler filling step of the fourth step of the present invention, the pre-drying step has a time of pre-drying for 5 to 60 minutes at 60 ~ 80 ℃; After the step of the pre-drying, to provide a thick copper PCB substrate manufacturing method having a step of drying for 40-80 minutes at 80 ~ 200 ℃ as a step of curing the filler.

In addition, the present invention is to provide a thick copper PCB substrate manufactured by the above-described manufacturing method in a multi-ply PCB.

The present invention relates to a method for manufacturing a thick copper PCB, which will be described in detail with reference to FIGS. 1 to 3.

The present invention is similar to the conventional one in that it is a method of manufacturing a thick copper PCB and its PCB.

However, it is a big feature that it is possible to eliminate the defects caused by the filler remaining in the through-holes after the filling of the through-holes after drilling of the fillers, copper plating, and the formation of the secondary circuit later. It will be described in detail with the accompanying drawings.

First, the present invention undergoes the first step: sandwiching the insulating layer 20 between the copper thin films 10, compressing and integrating the same, to fabricate the substrate 30.

That is, while preparing the copper foil film 10 is formed into a film, it is positioned up and down (shown in the first drawing of Figure 1).

At this time, the copper thin film 10 is of the same size, the shape having the same thickness or may be positioned up and down the copper thin film 10 of different thickness.

In addition, while pressing the copper thin film 10 and the insulating layer 20 at high temperature and high pressure, the insulating layer 20 is melted and fused with the copper thin film 10 so as to be integrated with each other as shown in FIG. .

However, the insulating layer 20 used in the first step of the present invention, it is preferable that the material of the epoxy, aramid or polyimide-based selectively.

These materials are all excellent in insulation and will be applied to the substrate 30 to increase the effect of the insulation.

Next, a second step: drilling a plurality of guide holes 33 in each corner of the four substrates of the integrated copper thin film 10 and the insulating layer 20.

In other words, the perforation is performed in a state in which the copper thin film 10 positioned vertically is accurately superimposed to provide a reference in a later work.

Therefore, if the guide hole 33 is matched to it, it is possible to match an accurate position of the primary circuit formed on the substrate 30.

In addition, the next step is a third step: forming a primary circuit to corrode the primary circuit GAP 40 to form a circuit on the copper thin film 10 forming the substrate 30 above and below.

That is, this step is to form a circuit shape on the upper and lower copper thin film 10, to corrode the primary circuit GAP 40 in the required portion.

That is, when the circuit is designed, the surface of the copper thin film is corroded in the developed state by photographing and exposing the same to form the primary circuit GAP 40.

Therefore, the copper thin film 10 has a plurality of primary circuits GAP 40 formed at necessary portions to have a shape as one circuit board.

Of course, all of these processes are well known and therefore are not described further.

In addition, the present invention is a fourth step: filling the filler 50 in the primary circuit GAP 40 of the copper thin film 10.

That is, as shown in the first drawing of FIG. 2, the filler 50 is filled in the groove portion in which the primary circuit GAP 40 is formed by corroding the copper thin film 10 through the three steps.

However, the filler 50 may be selectively used epoxy, polyimide, aramid, general resin, or heat radiation resin, these also characterized by high insulation effect.

However, as a method of filling the filler 50, many methods may be used.

In the present invention, the following method is used as a method of filling the filler 50 in this way.

That is, the filler 50 is filled in the primary circuit GAP 40 through silk printing, or a roll-filling technique, a dispensing technique and a spray method may be used.

Here, the silk printing method is a method of putting the filler 50 on the silk consisting of a mesh like a silk screen method and pushing it into a rubber, and in the case of the roll peeling method, the filler 50 is applied to the upper and lower parts of the substrate while the filler is buried in the roll. By rolling the filler 50 is pushed.

In the dispensing method, the filler 50 is put into a syringe or the like, and the filler 50 is squeezed into the primary circuit GAP 40. The spray method is a spraying method.
Next, dry for 40 to 80 minutes at 80 to 200 degrees.

On the other hand, the present invention is the following step, the fifth step: the surface of the copper thin film 10 filled with the filler 50 in the primary circuit GAP 40 is subjected to the flattening process.

That is, since the filler 50 is in a liquid state, the filler 50 may not be filled exactly with the height of the primary circuit GAP 40.

There is no choice but to keep the projecting state slightly upward as in the first drawing of FIG.

If so, there is a problem in forming the secondary circuit to be processed later, so in the present invention, it is necessary to process the filler 50 in the state protruded to maintain the flat surface.

Therefore, as shown in the second drawing of FIG. 2, the surface of the substrate copper thin film 10 on which the primary circuit is formed is processed to be flat.

This process is referred to as a flattening process in the present invention.

In the next step, a sixth step is performed: forming a hole 60 penetrating the top and bottom of the substrate 30.

In this step, the hole 60 may be drilled using a drill in a manner of forming the hole 60 in the substrate 30, and various methods such as a mechanical drill and a general biasing process may be used.

However, the hole 60 formed by the drill is preferably processed in a state that the inner circumferential surface is a little neat.

As a result, an important point in this step is to form the holes 60 between the upper copper foil film 10 and the lower copper foil film 10, as shown in the drawing where electricity is required to pass through each other.

In addition, after the sixth step of the present invention, the seventh step: plating the upper and lower portions of the hole 60 and the substrate 30 penetrating the upper and lower surfaces to form a plating layer 70.

That is, a copper film is coated to conduct electricity between the upper and lower copper thin films 10, and at this time, both the electroless plating method and the electroplating method may be used as a method of coating the copper film (plating layer: 70).

Then, as shown in the first drawing of FIG. 3, the inner circumferential surface of the hole 60 may also have a plating layer 70 formed thereon, and thus may conduct electricity between the two layers, and the copper thin film 10 forming the upper and lower surfaces of the substrate 30. The plating layer 70 which is a separate copper film is also formed outside.

Next, the present invention undergoes the eighth step: forming a secondary circuit to corrode the secondary circuit GAP 80 on the plating layer 70.

That is, the secondary circuit GAP 80 is corroded to the plating layer 70 formed on the upper and lower portions of the substrate 30. This method is also formed in the same manner as the formation of the primary circuit GAP 40 described above.

That is, if the circuit is designed, the surface of the copper thin film 10 is corroded in the developed state by photographing and exposing it to form the secondary circuit GAP 80.

Therefore, the plating layer 70 has a plurality of secondary circuit GAPs 80 formed at necessary portions to have a shape as one circuit board.

In this case, as shown in the second drawing of FIG. 3, a circuit must be formed so that the top of the filler 50 filled in the fourth step described above can be opened.

The accuracy of this position is really important, as the guide hole 33 described above is used when coating the photosensitive paper for securing this position.

The final step of the present invention is the ninth step: processing the surface of the plated substrate 30 and processing the external shape to complete the printed circuit board.

That is, a process of treating the surface of the substrate 30 is also required, and a process of trimming an external shape and a cutting process of cutting an appropriate portion may be used.

By the way, in the present invention, after the filling of the filler 70 of the fourth step, it is preferable to produce in the form of having a time of pre-drying for 5 to 60 minutes at 60-80 ℃ as a pre-drying step.

That is, this step prevents the phenomenon that bubbles are generated inside the filler 70, which may be generated when it is just cured.

It provides a framework that can be cured safely to predrying for a suitable time at a suitable temperature.

Of course, after this step, that is, after the step of the pre-drying, it may have a step of drying for 40-80 minutes at 80-200 ℃ as a step of curing the filler 70.

The temperature and time may vary slightly depending on the type of the filler 70, but the temperature and time are optimal values calculated by the applicant of the present invention through a number of experiments.

Therefore, it is desirable to maintain this temperature and time.

Meanwhile, in the present invention, the PCB substrate manufactured by all the above-described manufacturing methods in the multilayer PCB is also subject to the claims.

As described above, the present invention first corrodes the primary circuit GAP formed in the copper thin film, and then fills, dries and flattens the filler in the gap, and forms a secondary circuit for copper plating after drilling the through hole. This procedure has a big effect of eliminating solder defects due to residual fillers in the through-holes.

In addition, the present invention is simple in the manufacturing method, in the actual use, the cost is reduced, the manufacturing time is short and the PCB reliability is high.

Claims (6)

In the manufacturing method of a multi-ply PCB, First step: sandwiching the insulating layer 20 between the copper thin film 10, the step of pressing and integral to produce a substrate 30; A second step: drilling a plurality of guide holes 33 in four corner portions of the integrated copper thin film 10 and the insulating layer 20; A third step of forming a primary circuit to corrode the primary circuit GAP 40, which becomes a shape of a circuit, on the copper thin film 10 forming upper and lower portions of the substrate 30; Fourth step: filling the filler (50) in the primary circuit GAP (40) of the copper thin film (10); A fifth step: flattening the surface of the copper thin film 10 filled with the filler 50 in the primary circuit GAP 40; Sixth step: forming a hole (60) penetrating the top and bottom of the substrate (30); Step 7: forming a plating layer 70 by plating the entire upper and lower portions of the hole 60 and the substrate 30 penetrating the upper and lower surfaces in entirety; Eighth step: forming a secondary circuit to corrode secondary circuit GAP (80) on the plating layer (70);  The ninth step: processing the surface of the plated substrate, and processing the appearance to form a printed circuit board, characterized in that to form a printed circuit board. The method of claim 1, The insulating layer 20 used in the first step, Epoxy, aramid or polyimide-based material is selectively used, characterized in that the thickness copper PCB substrate manufacturing method. The method of claim 1, The filler of the fourth step, Epoxy-based, polyimide-based, aramid-based, general resin, or a heat-dissipating resin can be used selectively thick copper PCB substrate manufacturing method. The method of claim 1, After the filling step of the fourth step, Method of manufacturing a thick copper PCB substrate, characterized in that having a pre-drying time of 5-60 minutes at 60-80 ℃ in the step of pre-drying. The method of claim 4, wherein After the step of predrying, A method of manufacturing a thick copper PCB having a step of drying the filler at 80-200 ° C. for 40-80 minutes.  In a multilayer PCB, A copper copper PCB having a thickness thereof, which is manufactured through the manufacturing method of claim 1.

Images