KR102032377B1 - Method for forming hole in substrate - Google Patents

Abstract

According to an aspect of the present invention, a method for forming a hole in a substrate comprising a base member including a glass fiber, a resin material and a filler, the conductive layer is formed on the base member, wherein the hole is formed of a portion of the conductive layer Removing a portion to be exposed to expose a portion of the base member; and immersing the substrate in a filler removal liquid to remove the filler existing in an exposed portion of the base member; and etching the substrate into a resin etching solution. A resin removing step of immersing the resin material in the exposed portion of the base member; and immersing the substrate in water and applying a ultrasonic wave to the substrate; Spraying water; and immersing the substrate in a glass fiber etching solution and present in the exposed portion of the base member. Removing step of removing the glass fiber; and, dipping the substrate in water, the Second sonication step of applying an ultrasonic wave to the substrate, provides a substrate hole forming method comprising a.

Description

Method for forming hole in substrate

The present invention relates to a method of forming a hole in a substrate.

With the development of the electronic industry, the demand for miniaturization and multifunctionalization of electronic components is gradually increasing, and circuit boards on which electronic components are mounted are also required to be integrated at high density.

Accordingly, circuit boards have also been actively developed in a substrate having a multilayer structure. In a multilayer substrate structure or a structure of a double-sided substrate, holes such as via-holes and through holes that penetrate the substrate are provided. Is formed.

There are a number of methods for forming holes in a substrate. As an example, Korean Patent Laid-Open No. 2011-0123850 discloses a technique for forming via holes by laser drilling.

According to an aspect of the present invention, it is a main problem to provide a method for forming a hole in a substrate.

According to an aspect of the present invention, a method for forming a hole in a substrate comprising a base member including a glass fiber, a resin material and a filler, the conductive layer is formed on the base member, wherein the hole is formed of a portion of the conductive layer Removing a portion to be exposed to expose a portion of the base member; and immersing the substrate in a filler removal liquid to remove the filler existing in an exposed portion of the base member; and etching the substrate into a resin etching solution. A resin removing step of immersing the resin material in the exposed portion of the base member; and immersing the substrate in water and applying a ultrasonic wave to the substrate; Spraying water; and immersing the substrate in a glass fiber etching solution and present in the exposed portion of the base member. Removing step of removing the glass fiber; and, dipping the substrate in water, the Second sonication step of applying an ultrasonic wave to the substrate, provides a substrate hole forming method comprising a.

Here, the filler removal liquid may include a fluoride solution.

Here, the resin etching solution may include a sulfuric acid solution.

Here, in the water spraying step, the process of spraying the water is performed by a spray device, the pressure for spraying the water may be greater than 1kgf / ㎠.

Here, the glass fiber etching solution may include a fluoride solution.

Here, after performing the second sonication step, a water injection step of spraying water on the substrate may be further performed.

The substrate hole forming method according to an aspect of the present invention has the effect of forming a hole of excellent quality.

1 is a schematic cross-sectional view showing a state of a substrate before a hole H is formed according to an embodiment of the present invention.
FIG. 2 is a view illustrating a window formed in an etching process using an etching resist pattern on a conductive layer of a substrate according to an embodiment of the present invention.
3 is a schematic cross-sectional view showing a window formed in a conductive layer of a substrate according to an embodiment of the present invention.
4 is a view showing a state in which a filler existing in an exposed portion of a base member is removed by immersing a substrate in a filler removal liquid according to an embodiment of the present invention.
FIG. 5 is a view showing a state in which a resin material existing in an exposed portion of a base member is removed by immersing a substrate according to an embodiment of the present invention in a resin etching solution.
FIG. 6 is a diagram illustrating a state in which a substrate is immersed in water and ultrasonic waves are applied to the substrate according to an embodiment of the present invention.
FIG. 7 is a view illustrating a state in which water is sprayed on an exposed portion of the base member according to an exemplary embodiment of the present disclosure.
FIG. 8 is a view showing a state in which a glass fiber existing in an exposed portion of a base member is removed by immersing a substrate in a glass fiber etching solution according to an embodiment of the present invention.
FIG. 9 is a diagram illustrating a state in which a substrate is immersed in water and ultrasonic waves are applied to the substrate according to an embodiment of the present invention.
FIG. 10 is a schematic cross-sectional view showing a hole H formed on a substrate according to an embodiment of the present invention.
11 is a schematic flowchart illustrating steps of a method of forming a substrate hole in accordance with an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in this specification and drawing, duplication description is abbreviate | omitted by using the same code | symbol about the component which has substantially the same structure.

Hereinafter, a method of forming a hole in a substrate according to an embodiment of the present invention will be described with reference to FIGS. 1 to 11.

1 is a schematic cross-sectional view showing a state of a substrate before a hole H is formed according to an embodiment of the present invention, and FIG. 2 is an etching resist pattern on a conductive layer of the substrate according to an embodiment of the present invention. It is a figure which shows the form of a window by the used etching process. 3 is a schematic cross-sectional view showing a window formed in a conductive layer of a substrate according to an embodiment of the present invention, Figure 4 is a base member immersing the substrate in a filler removal liquid according to an embodiment of the present invention FIG. Is a view illustrating the removal of a filler present in an exposed part. 5 is a view showing a state in which a resin material existing in an exposed portion of a base member is removed by immersing a substrate according to an embodiment of the present invention in a resin etching solution, and FIG. 6 is an embodiment of the present invention. It is a figure which shows the state which immerses the board | substrate which concerns on water, and applies ultrasonic waves to a board | substrate. 7 is a view showing a state in which water is sprayed on the exposed portion of the base member according to an embodiment of the present invention, Figure 8 is a base immersing a substrate in a glass fiber etching solution according to an embodiment of the present invention Figure showing the removal of the glass fibers present in the exposed portion of the member. 9 is a view showing a state in which a substrate is immersed in water and ultrasonic waves are applied to the substrate according to an embodiment of the present invention, and FIG. 10 is a view in which a hole H is formed in the substrate according to an embodiment of the present invention. It is a schematic sectional drawing which shows. 11 is a schematic flowchart showing steps of a method of forming a substrate hole in accordance with an embodiment of the present invention.

First, the structure of the board | substrate 100 which concerns on one Embodiment of this invention used as the object of hole H formation operation | movement is demonstrated.

As shown in FIG. 1, the substrate 100 includes a base member 110 and a conductive layer 120, and has the characteristics of a flexible circuit board.

The base member 110 is made of a composite material in which a glass fiber 112 and a filler 113 are applied to a resin material 111 as a reinforcing base material. Have

As the resin material 111, an epoxy, a phenol, a polyimide, a liquid crystal polymer, a cyanate ester, an LCP, or another polymer material may be used. In addition, the resin material 111 may be made of not only a single material but also a composite material. In addition, the resin material 111 may have various types of internal structures. For example, the filamentary material and the small particle material can be mixed together to form the resin material 111.

Glass fiber 112 comprises a material of glass.

The filler 113 is preferably configured to include a silica-based material, for example, the filler 113 may include silicon dioxide (SiO ₂ ).

Meanwhile, the conductive layer 120 includes a copper (Cu) material and is formed on both sides of the base member 110, and the conductive layer 120 may be formed by a screen printing method, an inkjet printing method, a plating method, or the like. have.

The material of the conductive layer 120 according to the present embodiment includes copper, but the present invention is not limited thereto. That is, other conductive materials, for example, silver (Ag), gold (Au), or the like may also be used as the material of the conductive layer according to the present invention.

Since the base member 110 of the substrate 100 according to the present embodiment disperses and arranges not only the glass fiber 112 but also the filler 113 in the resin material 111, the base member 110 is excellent in high temperature thermal deformation characteristics and thus lower than that of the general substrate. It has the property of having a coefficient of thermal expansion.

In addition, the substrate 100 according to the present embodiment may be manufactured directly by the manufacturer to have a special structure, and as the substrate 100, a copper clad laminate including a glass fiber and a filler may be directly used.

The substrate 100 according to the present embodiment is configured to have the characteristics of the flexible circuit board, but the present invention is not limited thereto. That is, the substrate according to the present invention may have a feature of a rigid printed circuit board.

Since the substrate 100 according to the present exemplary embodiment has a panel shape, some processes of forming a hole H in the substrate 100 when the manufacturer directly performs the operation while moving the substrate 100 may be performed. It can be discontinuous. However, the present invention is not limited to this. That is, according to the present invention, the hole may be formed while transferring the substrate by a roll-to-roll process, in which case the hole formation time and the number of hole forming processes can be reduced.

Hereinafter, the process of forming the hole H in the substrate 100 described above will be described in detail with reference to FIGS. 2 to 11.

First, the manufacturer removes a portion of the conductive layer 120 where the hole H is to be formed to expose a portion of the surface of the base member 110 (step S1).

To this end, the manufacturer applies a photosensitive material to the surface of the conductive layer 120 and forms an etching resist pattern ERP by a photolithography process including an exposure and development process. Subsequently, as illustrated in FIG. 2, an etching process of etching the conductive layer 120 with an etching solution is performed using the formed etching resist pattern ERP. As a result, as shown in FIG. 3, a portion of the conductive layer 120 is removed to form a window W in the conductive layer 120.

According to the present embodiment, a photolithography process using a photosensitive material is used to remove a portion of the conductive layer 120 where the hole H is to be formed, but the present invention is not limited thereto. That is, another method may be used to remove the portion where the hole H is to be formed among the portions of the conductive layer 120 according to the present invention. For example, the window W may be formed in the conductive layer 120 by irradiating a laser.

Next, the manufacturer immerses the substrate 100 in the filler removal liquid FE and removes the filler 113 present in the exposed portion of the base member 110 (step S2).

That is, as shown in FIG. 4, the manufacturer dips the substrate 100 in the filler removal liquid FE contained in the filler removal liquid container FEB. Then, the filler removal liquid FE reaches the exposed part of the base member 110 through the window W formed in the conductive layer 120, and the reached filler removal liquid FE of the base member 110 Penetration of the exposed portion causes a chemical reaction to remove the filler 113.

Here, the filler removal liquid (FE) may include a fluoride solution. Examples of the fluoride solution may include an ammonium fluoride solution, a hydrofluoric acid solution, and the like. In the case of using an ammonium fluoride solution as the fluoride solution, the filler 113 is removed by the following chemical reaction formula.

3NH ₄ HF ₂ + SiO ₂ (filler)-> (NH ₄ ) ₂ SiF ₆ (sludge) + NH ₄ OH + H ₂ O

Then, the manufacturer removes the substrate 100 from the filler removal liquid FE, and then immerses the substrate 100 in the resin etching solution RE to remove the resin material 111 existing in the exposed portion of the base member 110. (Step S3).

That is, as shown in FIG. 5, the manufacturer dips the substrate 100 in the resin etching solution RE accommodated in the resin etching solution container REB. In that case, the resin etching solution RE reaches the exposed part of the base member 110 through the window W formed in the conductive layer 120, and the resin etching solution RE thus reached reaches the base member 110. The resin material 111 is removed by penetrating the exposed part to cause a chemical reaction.

Here, the type of the resin etching solution RE is determined according to the type of the resin material 111 applied to the substrate 100. For example, 70% high sulfuric acid may be used as the resin etching solution RE.

Next, the manufacturer removes the substrate 100 from the resin etching solution RE, and then performs a first ultrasonic treatment in which the substrate 100 is immersed in water and an ultrasonic wave is applied to the substrate 100 (step S4).

That is, as shown in FIG. 6, the manufacturer soaks the substrate 100 in the water contained in the first ultrasonic processing container UB1 and then drives the first ultrasonic apparatus UD1 to apply ultrasonic waves to the substrate 100. do. Then, the residues of the sludge of the filler 113 and the residue of the resin material 111 generated through the previous steps S2 and S3 are separated from the substrate 100 by the vibration generated in the first ultrasonic apparatus UD1. The adhesive force is relaxed and separated from the substrate 100.

Here, the distance d1 of the first ultrasound apparatus UD1 and the substrate 100 may not exceed 10 cm, and the ultrasound frequency may be selectively applied in the range of 28 kHz to 45 kHz.

In FIG. 6, the first ultrasound apparatus UD1 is disposed only below the substrate 100, but the present invention is not limited thereto. For example, the first ultrasound apparatus UD1 according to the present invention may be configured in a pair so as to face both sides of the substrate 100, so that ultrasonic waves may be simultaneously applied in both directions of the substrate 100. .

Then, the manufacturer removes the substrate 100 from the water contained in the ultrasonic processing container UB1, and then sprays water onto the substrate 100 at a predetermined pressure (step S5).

That is, as shown in FIG. 7, through the process of spraying water onto the substrate 100 at a predetermined pressure, the filler generated through the previous steps S2 to S4 by the impact force of the water hitting the substrate 100 ( The sludge of 113 and residues of the resin material 111 are removed from the substrate 100.

Here, the process of spraying water on the substrate 100 is performed using a spray device SP, the pressure for spraying water is preferably greater than 1kgf / ㎠, the spray nozzle (SPN) of the spray device (SP) It is preferable that the distance d2 between the substrate 100 and the substrate 100 does not exceed 20 cm.

In FIG. 7, the spray device SP is disposed in both directions of the substrate 100, but the present invention is not limited thereto. For example, the spray device SP according to the present invention may be arranged to face only one surface of the substrate 100, in which case an operator flips the substrate 100 during the process, and the water sprayed on the substrate 100 Work processes can be configured to evenly contact both sides.

As described above, in the present embodiment, the sludge and the resin of the filler 113 by successively performing the first ultrasonic treatment step (S4 step) and the water injection step (step S5 step) after the resin removal step (step S3). The residue of the material 111 can be removed reliably.

Next, the manufacturer dips the substrate 100 in the glass fiber etching solution GE to remove the glass fibers 112 present in the exposed portion of the base member 110 (step S6).

That is, as shown in FIG. 8, the manufacturer dips the substrate 100 in the glass fiber etching solution GE contained in the glass fiber etching solution container GEB. Then, the glass fiber etching solution GE reaches the exposed part of the base member 110 through the window W formed in the conductive layer 120, and the glass fiber etching solution GE reached is the base member 110. The glass fiber 112 is chemically reacted with the glass fiber 112 present in the exposed portion of the c) to remove the glass fiber 112.

Here, the glass fiber etching solution GE may include a fluoride solution. Examples of the fluoride solution may include an ammonium fluoride solution, a hydrofluoric acid solution, and the like. In the case of using an ammonium fluoride solution as the fluoride solution, the glass fiber 112 is removed by the following chemical reaction formula.

3NH ₄ HF ₂ + SiO ₂ (Glass Fiber)-> (NH ₄ ) ₂ SiF ₆ (sludge) + NH ₄ OH + H ₂ O

Here, the produced sludge form (NH ₄ ) ₂ SiF ₆ is reliably removed by the following second sonication process.

Next, the manufacturer removes the substrate 100 from the glass fiber etching solution GE, and then performs a second ultrasonic treatment in which the substrate 100 is immersed in water and an ultrasonic wave is applied to the substrate 100 (step S7).

That is, as shown in FIG. 9, the manufacturer soaks the substrate 100 in water contained in the second ultrasonic processing container UB2, and then drives the second ultrasonic device UD2 to apply ultrasonic waves to the substrate 100. Will be added. Then, the residues such as the sludge of the glass fiber 112 generated in the previous step S6, the adhesion force to the substrate 100 by the vibration generated in the second ultrasonic device UD2 is relaxed, the substrate 100 To be separated from.

Here, it is preferable that the separation distance d3 of the second ultrasonic apparatus UD2 and the substrate 100 does not exceed 10 cm, and the ultrasonic frequency is appropriately selected and applied in the range of 28 kHz to 45 kHz.

In FIG. 9, the second ultrasound device UD2 is disposed only below the substrate 100, but the present invention is not limited thereto. For example, the second ultrasound apparatus UD2 according to the present invention may be configured in a pair so as to face both sides of the substrate 100 so that the ultrasonic waves may be simultaneously applied in both directions of the substrate 100. .

As described above, when the process of step S1 to step S7 is performed, as shown in FIG. 10, the hole H is formed in the substrate 100.

According to this embodiment, there is no additional process after the second sonication step (step S7), but the present invention is not limited thereto. That is, according to the method for forming a substrate hole according to the present invention, the above-described water spraying step (S5 step) may be further performed after the second ultrasonic processing step (S7 step). In that case, it becomes possible to more reliably remove the glass fiber sludge residue that has not been completely removed even after the second sonication step.

In the substrate hole forming method according to the present embodiment described above, the filler removing step, the resin removing step, the first ultrasonic treatment step, the water spraying step, the glass fiber removing step, the second order to form the hole H By sequentially performing the ultrasonic treatment step, it is possible to form a high quality hole H having high straightness and uniformity.

In the substrate hole forming method according to the present embodiment, a large number of holes can be easily formed at a lower cost than the hole forming method by a mechanical drilling method or a laser drilling method that is generally used.

In addition, in the embodiment of the present invention in forming the hole (H) in the substrate 100 including the filler 113, by including a filler removing step for removing the filler 113 in the hole forming process, workability It is possible to form a high quality hole (H) at the same time by reducing the machining time.

While aspects of the present invention have been described with reference to the embodiments shown in the accompanying drawings, this is merely exemplary, and various modifications and equivalent other embodiments are possible from those skilled in the art. You will understand the point. Accordingly, the true scope of protection of the invention should be defined only by the appended claims.

INDUSTRIAL APPLICABILITY The present invention can be used in an industry for forming a hole in a substrate, or an industry for manufacturing an apparatus for forming a hole in a substrate.

100: substrate 110: base member
111: resin material 112: glass fiber
113: filler 120: conductive layer
H: Hall

Claims (6)

As a method of forming a hole in a substrate comprising a base member including a glass fiber, a resin material and a filler, the conductive layer formed on the base member,
Removing a portion of the conductive layer in which the hole is to be formed to expose a portion of the base member;
A filler removing step of dipping the substrate in the filler removing liquid to remove the filler present in the exposed portion of the base member;
A resin removing step of immersing the substrate in a resin etching solution to remove the resin material present in the exposed portion of the base member;
A first sonication step of dipping the substrate in water and applying ultrasonic waves to the substrate;
A water spraying step of spraying water onto the substrate;
A glass fiber removing step of dipping the substrate in a glass fiber etching solution to remove the glass fibers present in the exposed portion of the base member; And
And a second ultrasonication step of dipping the substrate in water and applying ultrasonic waves to the substrate. The method of claim 1,
The filler removal liquid comprises a fluoride solution. The method of claim 1,
The resin etching solution comprises a sulfuric acid solution. The method of claim 1,
In the water spraying step, the step of spraying water is performed with a spray device, the pressure for spraying the water is greater than 1kgf / ㎠. The method of claim 1,
And the glass fiber etching solution comprises a fluoride solution. The method of claim 1,
And performing a water spraying step of spraying water onto the substrate after performing the second ultrasonication step.

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