TW202011782A - Method for electroplating circuit board structure in hole - Google Patents

Abstract

The present disclosure discloses a method for manufacturing a circuit board structure, and the method includes: implementing a preparing step by providing a circuit board that has a hole having an aspect ratio larger than or equal to four; implementing a first electroplating step by using a first current of a first ampere square foot (ASF) value to electroplating the hole of the circuit board in a first period; and implementing a second electroplating step by using a second current of a second ASF value to electroplating the hole of the circuit board in a second period, wherein the first ASF value and the second ASF value are different from each other, and each of the first ASF value and the second ASF value is within a range of 4 ASF ~60ASF.

Description

Manufacturing method of circuit board structure

The invention relates to a circuit board, in particular to a method for manufacturing a circuit board structure.

Existing circuit board manufacturing methods all use a constant current density (that is, the current density remains constant) when performing hole plating on the circuit board. To achieve the effect of uniform plating, the existing circuit board manufacturing methods need to use A small current density increases the hole filling rate, but the above-mentioned smaller current density will increase the plating time, thereby reducing the plating efficiency.

Furthermore, the existing circuit board manufacturing methods have less influence on the plating time and plating efficiency when plating holes with an aspect ratio of less than 4, but with the development of circuit boards year by year, circuit boards need to be formed The proportion of holes with high aspect ratios is also getting higher and higher, so the existing circuit board manufacturing method also needs to be further improved for the plating method of holes with high aspect ratios.

Therefore, the inventor believes that the above-mentioned defects can be improved, and Naite devotes himself to research and cooperates with the application of scientific principles, and finally proposes a reasonable design and effectively improves the above-mentioned defects of the present invention.

An embodiment of the present invention is to provide a method for manufacturing a circuit board structure, which can effectively improve defects that may be generated by the existing circuit board manufacturing methods.

An embodiment of the present invention discloses a method for manufacturing a circuit board structure, including: performing a preparation step: providing a circuit board, and the circuit board includes a hole; wherein the hole has a depth divided by the hole diameter divided by the hole depth Ratio, and the aspect ratio is not less than 4; implement a first electroplating step: electroplating the holes of the circuit board with a first current within a first time period, and the first current has a A first current density value; and implementing a second electroplating step: electroplating the hole of the circuit board with a second current within a second time period, and the second current has a second current density value ; Wherein, the first current density value and the second current density value are different from each other, and each is between 4 ASF ~ 60 ASF.

An embodiment of the present invention also discloses a method for manufacturing a circuit board structure, including: performing a preparation step: providing a circuit board, and the circuit board includes a hole; wherein the hole has a depth divided by a hole depth Aspect ratio, and the aspect ratio is not less than 4; and N electroplating steps are sequentially performed: each of the electroplating steps electroplates the holes of the circuit board with a current, and the current has a current Density value; wherein, N is a positive integer not less than 2, and the N current electroplating steps include more than two kinds of the current density value, and any one of the current density value is between 4 ASF ~ 60ASF; Wherein, when any two of the electroplating steps performed in sequence, the difference between the two current density values used is greater than 2, a current conversion step is performed; wherein, the current conversion step is performed by a The stepped current plated the holes of the circuit board within a conversion period, and the stepped current has a stepped current density value, and the stepped current density value is within the conversion period from the two used Among the current density values, the current density value implemented before is gradually changed to the current density value implemented after; wherein the conversion period is between 0-20 minutes.

In summary, the manufacturing method of the circuit board structure disclosed in the embodiments of the present invention adopts multiple electroplating steps (such as: the first electroplating step and the second electroplating step) by using between 4 ASF ~ 60 ASF and each other The different current density values can effectively improve the plating efficiency and the plating effect (for example, to achieve a better filling rate) under the premise of taking into account the filling rate as much as possible.

In order to understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention, but these descriptions and drawings are only used to illustrate the present invention, not to make any protection to the scope of the present invention. limit.

1‧‧‧ circuit board

11‧‧‧hole

2‧‧‧Conductor

21‧‧‧Space

3‧‧‧Conductor

X‧‧‧ First current

Y‧‧‧second current

Z‧‧‧Step current

T1‧‧‧First period

T2‧‧‧Second period

Tc‧‧‧Conversion period

I‧‧‧ First current density value

Ⅱ‧‧‧ Second current density value

R‧‧‧Aperture

D‧‧‧hole depth

FIG. 1 is a schematic diagram of preparation steps of Embodiment 1 of a method for manufacturing a circuit board structure of the present invention.

FIG. 2 is a schematic diagram of the current density and time of the first electroplating step and the second electroplating step in Embodiment 1 of the manufacturing method of the circuit board structure of the present invention.

FIG. 3 is a schematic diagram of the circuit board structure after the implementation of the first embodiment of the manufacturing method of the circuit board structure of the present invention.

4 is a schematic diagram of the current density and time of the first electroplating step and the second electroplating step in the second embodiment of the manufacturing method of the circuit board structure of the present invention.

FIG. 5 is a schematic diagram of a circuit board structure after implementation of the second embodiment of the manufacturing method of the circuit board structure of the present invention.

FIG. 6 is a schematic diagram (1) of current density and time of the first plating step and the second plating step in Embodiment 3 of the manufacturing method of the circuit board structure of the present invention.

7 is a schematic diagram of the current density and time of the first plating step and the second plating step in the third embodiment of the manufacturing method of the circuit board structure of the present invention (2).

Please refer to FIG. 1 to FIG. 7, which are the embodiments of the present invention. It should be noted that this embodiment corresponds to the relevant quantity and appearance mentioned in the drawings, and is only used to specifically illustrate the implementation of the present invention. In order to facilitate understanding of the content of the present invention, rather than to limit the scope of protection of the present invention.

[Example 1]

It should be noted that, in order to facilitate the description of this embodiment, the drawings only show relevant partial structures. As shown in FIGS. 1 to 3, this embodiment discloses a method for manufacturing a circuit board structure, which includes a preparation step, a first electroplating step, and a second electroplating step. Wherein, any electroplating step in the manufacturing method of the circuit board structure of this embodiment may be implemented by an electroplating equipment (not shown), that is to say, various parameters in any electroplating step may be controlled by the electroplating equipment.

Furthermore, the manufacturing method of the circuit board structure of the present invention is not limited to the order or implementation of the above-mentioned multiple steps. For example, in other embodiments not shown in the present invention, the above steps can also be adjusted, changed, or increased or decreased according to actual design requirements. In addition, each step of the manufacturing method of the circuit board structure of this embodiment will be described below.

As shown in FIG. 1, the preparation step is implemented: a circuit board 1 is provided, and the circuit board 1 includes a hole 11. In this embodiment, the circuit board 1 may be a multi-layer board or a single-layer board, and the hole 11 is illustrated in FIG. 1 as a through hole penetrating the circuit board 1, but the invention is not limited thereto. For example, in other embodiments not shown in the present invention, the hole 11 may not penetrate a blind hole of the circuit board 1.

Furthermore, in this embodiment, the hole 11 has an aspect ratio (AR) of the hole diameter R divided by the hole depth D, and the aspect ratio is not less than 4. That is to say, the object or object applicable to the manufacturing method of the circuit board structure of this embodiment preferably excludes holes with an aspect ratio of less than 4.

As shown in FIG. 2, the first electroplating step is performed: the hole 11 of the circuit board 1 is electroplated with a first current X within a first time period T1, and the first current X has a first Current density value I. In this embodiment, the first period T1 is between 5 minutes and 80 minutes, and the first current density value I of the first current X is between 4 ASF and 60 ASF, but the invention is not limited to this . In the present embodiment, the above-mentioned ASF is used as a unit of current density, that is, ampere per square foot.

As shown in FIG. 2, the second electroplating step is carried out: the hole 11 of the circuit board 1 is electroplated with a second current Y in a second time period T2, and the second current Y has a second Current density value Ⅱ. In this embodiment, the second period T2 is between 5 minutes and 80 minutes, and the second current density II of the second current Y is between 4 ASF and 60 ASF, but the invention is not limited to this .

It should be noted that, as shown in FIGS. 2 and 3, the first current density value I and the second current density value II are different from each other, and the first current density value I and the second current density value II The difference is less than 2 in this embodiment, so that the first current density value I can be instantly converted to the second current density value II.

Furthermore, after performing the above steps, the manufacturing method of the circuit board structure is formed with a conductor 2 plated on the hole wall of the hole 11, and a space 21 is formed around the inner edge of the conductor 2.

Furthermore, in order to effectively form the conductor 2 in the hole 11, the first current density value I is preferably smaller than the second current density value II. The first current density value I is, for example, between 4 ASF and 12 ASF, and the second current density value II is, for example, between 10 ASF and 30 ASF.

[Example 2]

Please refer to FIG. 4 and FIG. 5, which is the second embodiment of the present invention. This embodiment is similar to the above-mentioned first embodiment, so the similarities (eg, preparation steps) of the two embodiments will not be repeated, and The difference between this embodiment and the first embodiment mainly lies in that: after the manufacturing method of the circuit board structure of this embodiment is implemented, a conductive body 3 that is plated on the holes 11 is formed.

Specifically, in order to effectively form the conductor 3 in the hole 11, the first current density value I is preferably greater than the second current density value II. The first current density value I is, for example, between 10 ASF and 60 ASF, and the second current density value II is, for example, between 4 ASF and 15 ASF.

[Embodiment 3]

Please refer to FIG. 6 and FIG. 7, which is the third embodiment of the present invention. This embodiment is similar to the above-mentioned first and second embodiments, so the same points of the above-mentioned embodiments (such as: preparation step, first electroplating step, and The second electroplating step) will not be repeated here. The difference between this embodiment and the first and second embodiments is that the manufacturing method of the circuit board structure of this embodiment is between the first electroplating step and the second electroplating step. A current conversion step is further implemented.

Specifically, the current conversion step is implemented as follows: the hole 11 of the circuit board 1 is plated with a step current Z within a conversion period Tc, and the step current Z has a step current density value. Wherein, the aforementioned step current density value gradually changes (eg, increases or decreases) from the first current density value I to the second current density value II within the conversion period Tc.

In this embodiment, the conversion period Tc is between 0 and 20 minutes, and the length of the conversion period Tc is roughly based on the difference between the first current density value I and the second current density value II Decision, but the invention is not limited to this. Furthermore, after the actual operation of the manufacturing method of the circuit board structure of this embodiment, the following correspondence table of the relationship between the current density difference and the conversion period Tc is obtained.

According to the above table, when the difference between the first current density value I and the second current density value II is less than 2, the conversion period Tc is 0 minutes, which is equivalent to the first and second embodiments The recorded first current density value I is instantly converted to the second current density value II.

Furthermore, when the difference between the first current density value I and the second current density value II is between 3 and 5, the conversion period Tc is 1 to 11 minutes; the first current density value I and the second current When the difference between the density values II is between 6 and 9, the conversion period Tc is 12 to 19 minutes; when the difference between the first current density value I and the second current density value II is more than 10, the conversion period Tc For 20 minutes.

According to this, the manufacturing method of the circuit board structure of this embodiment can adjust the length of the conversion period Tc according to the difference between the first current density value I and the second current density value II, thereby enabling the above-mentioned circuit board 1 The hole 11 has better plating effect and plating efficiency.

It should be additionally noted that the first to third embodiments described above are described with two electroplating steps (such as the first electroplating step and the second electroplating step), but the number of electroplating steps implemented by the manufacturing method of the circuit board structure of the present invention is not This is the limit.

Further, in an embodiment not shown in the present invention, the manufacturing method of the circuit board structure may be to sequentially implement N electroplating steps, and N is a positive integer not less than 2; wherein, each electroplating In the step, the hole 11 of the circuit board 1 is electroplated with a current, and the current has a current density value. Furthermore, the above N electroplating steps include two or more current density values, and any one of the current density values is between 4 ASF and 60 ASF.

More specifically, when any two of the electroplating steps performed in sequence, the difference between the two current density values used is greater than 2, a current conversion step is performed; In the electroplating step performed sequentially, when the difference between the two current density values used is less than 2, the two current density values can be converted in an instant.

In the current conversion step, the hole 11 of the circuit board 1 is electroplated in a conversion period with a step current, and the step current has a step current density value, and the step current density value is During the conversion period, the current density value that is implemented earlier from the two used current density values gradually changes to the current density value that is implemented later. Furthermore, the conversion time period is between 0 and 20 minutes, and the specific time length can be referred to in the third embodiment.

It should be additionally noted that the current density values used in the above N electroplating steps can be controlled according to actual needs: from high to low, from low to high, or alternate between high and low, and the invention is not limited herein.

In addition, for the existing circuit board manufacturing method, under the premise of taking into account the filling rate as much as possible, the plating efficiency for holes with an aspect ratio greater than 4 and less than 8 will be reduced by 10%, and for the aspect ratio greater than 8 and Electroplating efficiency for holes less than 11 will be reduced by 40%, while for holes with an aspect ratio greater than 11 and less than 16, the plating efficiency will be reduced by 70%. Among them, the existing circuit board manufacturing method is difficult to achieve a hole filling rate of 60% for holes with an aspect ratio greater than 11 and less than 16.

However, after actual operation of the manufacturing method of the circuit board structure of this embodiment, under the premise of taking into account the filling rate as much as possible, the plating efficiency of the holes 11 with an aspect ratio greater than 4 and less than 16 is compared with the existing circuit board manufacturing In terms of methods, they can be effectively improved. Furthermore, the manufacturing method of the circuit board structure disclosed in the embodiment of the present invention can achieve a hole filling rate of the hole 11 with an aspect ratio greater than 11 and less than 16 and can reach more than 60%.

[Technical Effects of Embodiments of the Invention]

In summary, the manufacturing method of the circuit board structure disclosed in the embodiments of the present invention adopts multiple electroplating steps (such as: the first electroplating step and the second electroplating step) by using between 4 ASF ~ 60 ASF and each other The different current density values can effectively improve the plating efficiency and the plating effect (for example, to achieve a better filling rate) under the premise of taking into account the filling rate as much as possible.

Furthermore, the manufacturing method of the circuit board structure of this embodiment can further adjust the conversion according to the difference between the current density values of the two plating steps (eg, the difference between the first current density value and the second current density value) The length of the period of time can make the holes of the circuit board have better plating effect and plating efficiency.

The above are only the preferred and feasible embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any changes and modifications made within the scope of the patent of the present invention shall fall within the scope of protection of the claims of the present invention.

X‧‧‧ First current

Y‧‧‧second current

Z‧‧‧Step current

T1‧‧‧First period

T2‧‧‧Second period

Tc‧‧‧Conversion period

I‧‧‧ First current density value

Ⅱ‧‧‧ Second current density value

Claims (10)

A method for manufacturing a circuit board structure includes: performing a preparation step: providing a circuit board, and the circuit board includes a hole; wherein the hole has an aspect ratio of the hole diameter divided by the hole depth, and the The aspect ratio is not less than 4; implement a first electroplating step: electroplating the holes of the circuit board with a first current within a first time period, and the first current has a first current density value And a second electroplating step: electroplating the holes of the circuit board with a second current in a second period, and the second current has a second current density value; wherein, the The first current density value and the second current density value are different from each other, and each is between 4 ASF and 60 ASF. The method for manufacturing a circuit board structure according to claim 1, which is implemented to form a conductor plated on the hole wall of the hole, so that the inner edge of the conductor body surrounds to form a space, and the first A current density value is less than the second current density value. The method for manufacturing a circuit board structure according to claim 2, wherein the first current density value is between 4 ASF and 12 ASF, and the second current density value is between 10 ASF and 30 ASF. The method for manufacturing a circuit board structure according to claim 1, which is implemented to form a conductor plated over the hole, and the first current density value is greater than the second current density value. The method for manufacturing a circuit board structure according to claim 4, wherein the first current density value is between 10 ASF and 60 ASF, and the second current density value is between 4 ASF and 15 ASF. The method for manufacturing a circuit board structure according to claim 1, further comprising: performing a current conversion step between the first electroplating step and the second electroplating step: applying a step current to the circuit board The hole is electroplated in a conversion period, and the step current has a step current density value, and the step current density value gradually changes from the first current density value to the step during the conversion period The second current density value; wherein, the conversion period is between 0-20 minutes. The method for manufacturing a circuit board structure according to claim 6, wherein when the difference between the first current density value and the second current density value is 2 or less, the conversion period is 0 minutes; When the difference between a current density value and the second current density value is more than 10, the conversion period is 20 minutes. The method for manufacturing a circuit board structure according to claim 6, wherein when the difference between the first current density value and the second current density value is between 3 and 5, the conversion period is 1 to 11 minutes . The method for manufacturing a circuit board structure according to claim 6, wherein when the difference between the first current density value and the second current density value is between 6-9, the conversion period is 12-19 minutes . A method for manufacturing a circuit board structure includes: performing a preparation step: providing a circuit board, and the circuit board includes a hole; wherein the hole has an aspect ratio of the hole diameter divided by the hole depth, and the The aspect ratio is not less than 4; and N electroplating steps are performed in sequence: each of the electroplating steps electroplats the holes of the circuit board with a current, and the current has a current density value; wherein, N Is a positive integer not less than 2, and the N current electroplating steps include two or more of the current density values, and any one of the current density values is between 4 ASF ~ 60 ASF; In the electroplating step performed in sequence, when the difference between the two current density values used is greater than 2, a current conversion step is performed; wherein, the current conversion step uses a stepped current to the circuit The hole of the board is electroplated in a conversion period, and the step current has a step current density value, and the step current density value is in the conversion period from the two current density values used The current density value implemented before is gradually changed to the current density value implemented after; wherein, the conversion period is between 0-20 minutes.

Images