KR100680739B1 - Method for manufacturing substrate and wetting enhancement apparatus - Google Patents

Abstract

A method for manufacturing a substrate and improving humidity of the substrate is provided to facilitate the removal of an organic oxide film by removing an air bubble in a cleaning step. A method for manufacturing a substrate and improving humidity of the substrate includes the steps of: improving the humidity of the substrate(205); cleaning the substrate(210); washing the cleaned substrate(215); performing soft etching for the washed substrate; further washing the soft-etched substrate; and performing a pre dip for the washed substrate(220).

Description

Substrate manufacturing method and substrate wettability improving device {Method for Manufacturing Substrate and Wetting Enhancement Apparatus}

1 is a view showing a method of manufacturing a substrate according to an embodiment of the present invention;

2 is a flow chart showing a plating process according to a preferred embodiment of the present invention;

3 and 4 illustrate problems that may occur when a substrate is manufactured according to the process of FIG. 2;

5 is a flow chart showing a plating pretreatment process according to a preferred embodiment of the present invention;

6 is a substrate plated according to a preferred embodiment of the present invention; And

7 is an apparatus for improving substrate wettability according to an exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

100: insulating layer 110: conductive layer

120: dry film 130: plating layer

140: organic oxide film 150: air bubbles

310 bath 320 sprayer

330: blower 340: humectant mist (mist)

350: substrate

The present invention relates to a substrate manufacturing method, and more particularly to a pretreatment step in the plating process of the substrate.

In general, in order to manufacture a printed circuit board, an internal circuit pattern is formed on a substrate forming a core. After forming a predetermined circuit pattern by using a dry film or a working film, the copper foil layer is etched along the circuit pattern, and the preliminary lamination and Perform the lamination process. The laminated substrate is pressurized, and a drill process for performing hole processing for electric conduction between each layer is performed. Thereafter, a dry film and a work film for forming a circuit pattern are applied to the outer layer again, and an outer layer developing operation is performed through exposure and development, and an etching process of etching the exposed base layer by removing the dry film by developing is performed. After circuit optical inspection and scale measurement, a solder resist ink is produced through a series of processes such as coating, curing, exposure, development, and post curing. The copper foil layer exposed by removing the solder resist ink is subjected to surface treatment of gold plated HASL, OSP, and the like.

The stable formation of the plating layer during the plating of the substrate is an important problem as it is directly connected to the reliability of the entire substrate. Such stable formation of the plating layer is also closely related to the pretreatment step of the plating process. For example, in the exposure or shape process of the dry film as a previous step, the dry film of the portion forming the wiring is not completely removed and is formed on the substrate. It can remain and they can be exposed to air to form an organic oxide film. In order to remove the organic oxide film, a pretreatment step of the plating process is performed, and one of the pretreatment steps includes a cleaner step. In this cleaner stage, when the substrate is rapidly immersed in the liquid cleaner, minute air bubbles are formed in the holes, thereby trapping or blocking the entire hole. Therefore, there is a problem in that the organic oxide film is not removed and the reduction is prevented during plating, thereby partially plating the hole or not plating at all.

The present invention provides a method of manufacturing a substrate comprising the step of improving the wettability in the plating pretreatment step of the substrate.

In addition, the present invention provides a substrate manufacturing method and a wettability improving apparatus for spraying the wetting agent mist into the surface and the hole of the substrate to improve the wettability of the substrate. The present invention also provides a substrate manufacturing method and a wettability improving apparatus for improving the wettability of the substrate before the cleaner step so that no air bubbles remain on the substrate in the cleaner step. In another aspect, the present invention provides a substrate manufacturing method and a wettability improving apparatus to improve the wettability on the substrate to facilitate the removal of the organic oxide film.

According to an aspect of the present invention, in the plating pretreatment step of the substrate, it provides a substrate manufacturing method comprising (a) a wettability improvement step, (b) a cleaner step and (c) a pre dip step can do.

Here, before the step (c) may further comprise a washing step.

In addition, the step (b ') before the step (c) may further comprise a soft etching step.

In addition, it may further include a washing step before and after the step (b ').

In addition, the step of improving the wettability may include the step of changing the wetting agent into a mist (mist) form, the step of spraying the wetting agent mist to the substrate and the step of attaching the wetting agent mist to the substrate.

The wetting agent here may be one or more surfactants selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants.

In addition, the humectant may be an aqueous solution of one or more compounds selected from the group consisting of alkylbenzenesulfonates, aminehalogen compounds, quaternary ammonium salts, alkylpyridinium salts, amino acids, polyethylene glycols, and polyethylene nonyl phenyl ethers.

In addition, the humectant may be changed into a mist form by ultrasonic waves.

According to another aspect of the present invention, it is possible to present a substrate manufactured by the above-described manufacturing method.

According to another aspect of the invention, the bath (bath) having a receiving space of the size corresponding to the size of the substrate, the sprayer for changing the wetting agent into the mist (mist) located outside the bath and the sprayer and the bath Located in between may include a blower for supplying the mist to the space.

Here, the nebulizer may include an ultrasonic generator.

Hereinafter, preferred embodiments of the substrate manufacturing method and the substrate wettability improving apparatus according to the present invention will be described in detail with reference to the accompanying drawings. In addition, before describing the preferred embodiments of the present invention in detail, a plating process including a substrate manufacturing method and pretreatment will be described first.

1 is a view showing a method of manufacturing a substrate according to an embodiment of the present invention. Hereinafter, referring to FIG. 1, in step (a), a thin conductive layer 110 is formed on the insulating layer 100 including the internal circuit board by, for example, electroless copper plating. In step (b), a photoresist layer such as a dry film 120 is laminated to form a wire in the conductive layer. Thereafter, in step (c), portions unnecessary for circuit formation are exposed through exposure and development processes. In step (d), the plating layer 130 is formed to a desired height through electroplating, and in step (e), the dry film 120 is removed, and in step (d), insulation is performed by a method such as flash etching. The thin conductive layer 110 on the layer is etched to complete the circuit.

Here, to form the plating layer 130 as in step (d) is subjected to a pretreatment process. 2 is a flowchart illustrating a pretreatment step of a plating process according to an exemplary embodiment of the present invention. Referring to FIG. 2, in order to load the substrate on the pretreatment plate in step 200 and to remove organic substances generated in the pretreatment process such as photoresist remaining on the substrate in step 210, to improve adhesion in a subsequent plating process. Go through the cleaner stage. At the same time, conditioner treatment may be performed depending on which stage of the substrate formation process. In step 215, it is washed with water to remove the cleaner, and in step 200, a thin oxide film is removed on the surface of the conductive layer to improve the adhesion of the copper ions reduced in the electroplating bath, preventing incomplete connection and remaining on the surface of the substrate and flowing into the plating bath. A pre dip is performed to prevent the concentration change of the electrophoretic liquid from the washing water. In the case of using a colloidal catalyst when pre-dip, it is preferable that the liquid property is managed as a strong acid to prevent a sudden pH change of the catalyst. In one preferred embodiment of the present invention, sulfuric acid is used. Prior to this pre-dip step, the process of selectively soft etching and washing with water may be further processed. This soft etching serves to improve the adhesion between the conductive layer and the plated copper by etching the surface of the conductive layer, and a mixture of sulfuric acid and hydrogen peroxide or sulfuric acid and persulfuric acid is commonly used.

In addition, when such a plating process is performed on the insulating layer, the catalyst may be adsorbed on the insulating layer and washed with water, followed by a reduction (promoting) step and washing with water to obtain a Pd metal that actually acts as a catalyst. In addition, in order to improve adhesion between the insulating layer and the plating layer, a chemical copper plating process of depositing copper through a chemical reaction may be further performed. Such chemical copper plating is also referred to as electroless plating and is a plating process in which a reaction is accelerated by a Pd catalyst and the reaction is further activated by a hydrogen gas generated by the reaction. The acid treatment step of neutralizing the base obtained by the chemical copper plating process with an acid to give the same liquidity as that of copper may be further processed.

In step 225, electroplating is performed to deposit copper electrically. In general, the electroplating solution may serve as an accelerator of copper ions and plating. In the case of a soluble anode, chlorine ions are added to help form a black film, and sulfuric acid is added to the plating solution to improve conductivity of the plating solution. In order to control, additives such as a brightening agent and a smoothing agent may be added. After washing as step 230, and optionally to prevent the oxidation of the surface of the plated plating layer may be further subjected to an oxidation step. Thereafter, in step 240, the plated substrate is unloaded from the plate.

3 and 4 illustrate problems that may occur when a substrate is manufactured according to the process of FIG. 2. In general, in the cleaning process such as step 210, the substrate is rapidly dried vertically with the liquid cleaner liquid while the (micro) holes and the surface of the substrate are dried. In this case, air bubbles are formed on the inner wall and the bottom of the (micro) holes and the surface of the substrate. Is formed.

Referring to FIG. 3A, such fine air bubbles 150 form a trap, thereby preventing the organic oxide layer 140 from being removed. Therefore, when the plating layer 130 is formed as shown in FIG. 3B, the organic oxide layer 140 that prevents the conduction between the conductive layer 110 and the plating layer 130 remains. In addition, referring to FIG. 4A, when the air bubble 150 is large, the entire hole is blocked, and as shown in FIG. 4B, reduction of copper ions is prevented during electroplating. The plating layer 130 may be partially or not formed therein. This may cause product defects or delamination of the substrate.

The present invention improves the wettability of the substrate in order to improve the problems caused by the air bubbles 150, so that the organic oxide film 140 can be reliably removed and the plating layer 130 can be stably formed. Hereinafter, a preferred embodiment of the present invention will be described in detail.

5 is a flowchart illustrating a plating pretreatment process according to an exemplary embodiment of the present invention. Referring to FIG. 5, the wettability improvement step as in step 205 is performed before performing the cleaning process of step 210 in comparison with FIG. 2. Wherein the step of improving the wettability includes changing the wetting agent into a mist form, spraying the wetting agent mist onto the substrate, and attaching the wetting agent mist to the substrate. Here, as the wetting agent, one or more surfactants selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants may be used. Examples of the wetting agent include, but are not limited to, alkylbenzenesulfonates as anionic surfactants, amine halogen compounds as cationic surfactants, quaternary ammonium salts, alkylpyridinium salts, amino acids as amphoteric surfactants, and polyethylene glycols as nonionic surfactants. And polyethylene nonyl phenyl ether. In addition, according to a preferred embodiment of the present invention, the humectant may be converted into a mist (mist) form by ultrasonic waves, and the humectant mist may be sprayed by the vortex.

6 shows a substrate to be plated according to one preferred embodiment of the present invention. Referring to FIG. 6, in order to form the plating layer 130 on the substrate on which the conductive layer 100 is formed on the insulating layer 100 in FIG. 6A, the dry film 120 is exposed and developed to form the plating layer 130. The part to be formed was removed. When the thus formed substrate is treated with a wettability mist to improve wettability on the substrate, and a cleaner step is performed, air bubbles are not formed on the substrate, and the organic oxide film is also neatly removed. Therefore, when the electroplating is performed, as shown in FIG. 6B, a uniform, continuous, and electrically conductive plating layer 130 can be formed.

Thus, an apparatus for improving the wettability of the substrate is shown in FIG. 7. Referring to FIG. 7, according to a preferred embodiment of the present invention, a bath having an accommodation space having a size corresponding to the size of the substrate is shown. 310, an atomizer 320 positioned outside the bath 310 to change a humectant into a mist form, and positioned between the atomizer 320 and the bath 310 to provide the mist 340. It is possible to provide a substrate wettability improving apparatus including a blower 330 for supplying the space.

Here, one surface of the bath 310 may be automatically closed when entering the substrate to prevent the outflow of the mist. In addition, the nebulizer 320 may convert the liquid containing the humectant into the mist form using ultrasonic waves, and the blower 330 may form a vortex to supply mist formed in the nebulizer to the bath.

The present invention is not limited to the above embodiments, and many variations are possible by those skilled in the art within the spirit of the present invention.

As described above, the method of manufacturing a substrate according to the present invention includes a step of improving wettability in a plating pretreatment step of the substrate. In addition, the manufacturing method and the wettability improving apparatus of the substrate according to the present invention by spraying the wetting agent mist into the surface and the hole of the substrate to improve the wettability of the substrate, to improve the wettability of the substrate before the cleaner stage, air bubbles remain on the substrate in the cleaner stage The organic oxide film can be easily removed.

Although described with reference to a preferred embodiment of the present invention, those skilled in the art to which the present invention described in the appended claims and various equivalents and scope of the present invention without departing from the equivalent spirit and scope It will be understood that modifications and variations are possible.

Claims (11)

In the plating pretreatment step of the substrate, (a) improving wettability; (b) a cleaner step; And (c) A method of manufacturing a substrate comprising a pre dip step. The method according to claim 1, Substrate manufacturing method further comprising a washing step before step (c). The method according to claim 1, And (b ') soft etching prior to step (c). The method according to claim 3, Substrate manufacturing method further comprising a washing step before and after step (b ') step. The method according to claim 1, The wettability step is Changing the wetting agent into a mist (mist) form; Spraying the humectant mist onto a substrate; And And attaching the humectant mist to the substrate. The method according to claim 5, And the wetting agent is at least one surfactant selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants. The method according to claim 6, Wherein the wetting agent is an aqueous solution of at least one compound selected from the group consisting of alkylbenzenesulfonates, aminehalogen compounds, quaternary ammonium salts, alkylpyridinium salts, amino acids, polyethylene glycols, and polyethylene nonyl phenyl ethers. The method according to claim 5, The wetting agent is a substrate manufacturing method that is changed into a mist (mist) form by ultrasonic waves. The substrate manufactured by the manufacturing method of any one of Claims 1-8. A bath having a receiving space of a size corresponding to the size of the substrate; An atomizer positioned outside the bath to change the humectant into a mist form; And And a blower positioned between the sprayer and the bath to supply the mist to the space. The method according to claim 10, The atomizer is a substrate wettability improving apparatus comprising an ultrasonic generator.

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