KR101980609B1 - EMI Shielding Coating Method for Smart Car, Mobile Device and Wearable Device - Google Patents

Abstract

Provided is a method for performing an electromagnetic interference shielding coating operation on the surface of a metal or a nonmetal material, comprising: a preprocess step of cleaning the surface of the material and performing a dry surface etching operation before coating; a surface seed replacement forming step of forming a metal seed layer on the preprocessed surface; a first plating step of performing an electroless plating operation on a surface of the seed layer by a first metal having a basic shielding function; and a second plating step of performing an electroless plating operation on a surface of the first metal plating layer by a second metal having a finishing shielding function, wherein the first metal is copper (Cu) and the second metal is tungsten (W). The present invention provides the electromagnetic interference shielding coating method which can be applied to the surface of components of a smart car, a mobile device and a wearable device, and has excellence in an electromagnetic interference shielding effect, coating durability, manufacturing time and economic feasibility for costs.

Description

TECHNICAL FIELD [0001] The present invention relates to an EMI shielding coating method for a smart car, a mobile device, and a wearable device,

The present invention relates to a method for shielding electromagnetic wave shielding on the surface of a metal or nonmetal material, comprising a pretreatment step of cleaning the surface of the material and dry-etching the surface before coating, a surface seed substitution forming step of forming a metal seed layer on the pretreated surface, And a second plating step of performing electroless plating of the second metal on the surface of the first metal plating layer by performing electroless plating of a basic shielding function with a first metal on the surface, Wherein the first metal is Cu (copper), and the second metal is W (tungsten). The method is applicable to surfaces of components of smart cars, mobile devices, and wearable devices , Electromagnetic wave shielding effect, coating durability, production time and economical cost.

It is reported that the electromagnetic wave can induce various diseases including cancer. International cancer research institute under the United Nations has classified the electromagnetic wave as a carcinogenic substance and prescribes it as a carcinogenic substance. . In addition, electromagnetic waves affect other adjacent electronic devices, and there is a problem such as electromagnetic wave interference, malfunction of electronic equipment due to noise, deterioration of signal quality, and the importance of electromagnetic wave shielding function is increasing.

In modern society where the use of electronic devices is commonplace, as the opportunities for exposure to electromagnetic waves become more frequent, various methods for blocking electromagnetic waves have been attempted. In addition, as frequency bands of electromagnetic waves generated along with the development of various electronic apparatuses are widened, researches on a method capable of blocking electromagnetic waves of as wide a range as possible have become more active.

As a method for shielding electromagnetic waves, there is a method of preventing the electromagnetic wave from being emitted to the human body by forming the case of the conductive material on the surface of the electronic device. However, an unnecessary space is formed between the case and the semiconductor chip, There is a problem that the volume is increased, and the electromagnetic wave shielding case which generates an unnecessary space has a problem that it is arranged to meet the demand of the consumer for miniaturization of the electronic device.

To solve these problems, a method of forming a metal coating layer for shielding electromagnetic waves directly on parts of an electronic device has been introduced. The shielding function of electromagnetic waves has a high conductivity, and its function is further improved as the amount and surface area of the conductive material is increased. However, a mixed solution containing metal particles with high conductivity and high corrosion resistance such as silver (Ag) There is a problem in that it is impossible to completely block the electromagnetic wave from the surface of the component by spray coating the surface of the component. Further, since it is impossible to completely block the electromagnetic wave, use of high-conductivity silver particles having a high manufacturing cost as a rare metal has caused the manufacturing cost of the electromagnetic shielding functional electronic device to be improved.

In order to solve the above problems, an electromagnetic shielding coating method using a sputtering method in which a metal thin film is directly formed on the surface of a component is introduced. However, in order to form a coating layer having an electromagnetic shielding effect, There is a problem that the productivity is deteriorated.

Korean Patent No. 10-1830059 discloses a coating composition for shielding electromagnetic waves, wherein a coating composition that can be coated on an outer layer of an electronic device includes a binder such as polyurethane, wherein an organic ionic conductive agent, A non-yellowing curing agent and an additive so as to form a colorless coating film and has an effect of controlling electromagnetic waves.

However, as described above, the present invention forms a coating film on the surface of an electronic device and forms a coating film with a coating composition containing a binder component. The present invention relates to an electromagnetic wave chafing coating composition including a binder, There is a problem in that the electromagnetic wave shielding effect is inferior to the method of shielding the electromagnetic wave in the unit of the electronic device as a method of coating the outer layer of the electronic device.

Korean Patent Laid-Open No. 10-2016-0090771 discloses a tungsten alloy plating method and a tungsten alloy plating material, which discloses a method of forming a tungsten alloy plating on the surface of a metal or a nonmetal material, It is disclosed that by forming an alloy plating layer, electromagnetic shielding and corrosion resistance can be favorable.

However, in the case of the above technique, there is a problem that the process is complicated because a multilayer metal layer must be formed. In the case of a plating or a coating layer formed by laminating a plurality of metal layers, some defects may occur in one layer of the multilayer, There is a problem that the layer stacked on the upper surface thereof is not formed properly in the next step. Furthermore, since a plurality of layers are each formed of a metal layer, when a defect occurs, it is impossible to separate the coating layer from the coating material, so that there is a problem of a large loss in process cost due to a high defect rate and a low recycling rate.

Accordingly, it is urgently required to develop a technique for electromagnetic shielding coating method which is capable of shielding electromagnetic waves at the component level and thus can be applied to very small parts, thereby improving the electromagnetic wave shielding ratio and saving production cost and time, to be.

Korean Patent No. 10-1830059 Korean Patent Publication No. 10-2016-0090771

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems that have been required from the past.

The present invention relates to a method for shielding electromagnetic wave shielding on the surface of component parts of electronic equipment, which is capable of shielding electromagnetic waves from a part-by-part basis, thereby shielding electromagnetic waves of a wide bandwidth at low cost, To an electromagnetic wave shielding coating method in which the coating layer is not separated even in the case of moisture and high temperature, and the corrosion resistance is excellent and the electromagnetic wave shielding effect is maintained for a long time.

Specifically, the electromagnetic wave shielding coating method according to the present invention is a method of shielding electromagnetic wave shielding on the surface of a metal or a nonmetal material, comprising a pretreatment step of cleaning the surface of the material and etching the dry surface before coating, A first plating process for performing electroless plating of a basic shielding function with a first metal on the surface of the seed layer, and electroless plating of a second metal having a finishing shielding function on the surface of the first metal plating layer Wherein the first metal is Cu (copper), and the second metal is W (tungsten).

The present invention relates to an electromagnetic wave shielding coating method, wherein a thickness of a first plating layer formed through the first plating process is 0.05 to 5 탆 (micrometer).

In the electromagnetic shielding coating method of the present invention, the thickness of the second plating layer formed through the second plating process is 1 to 10 탆 (micrometer).

In the present invention, the thickness of the seed layer may be 0.05 to 5 탆 (micrometer). Specifically, in the surface seed substitution formation process, the metal contained in the seed layer is Pd (palladium) And the surface of the workpiece is immersed in a palladium sulfate solution having 5 to 20 g / L, which satisfies 30 to 80 캜, for 1 to 10 minutes to electrolessly coat the surface of the workpiece.

On the other hand, in the case where the surface seed substitution forming process is Ni (nickel) and Fe (iron) as the metal included in the seed layer, under the condition that the temperature is 150 to 250 ° C. and the degree of vacuum is 10 ^-5 to 10 ^-3 mmHg, Wherein the surface of the workpiece is coated with a metal plasma by sputtering for 1 to 15 minutes.

The present invention is also characterized in that the surface of the substrate having the seed layer formed thereon in a copper chloride solution having a pH of 8 to 10 and a temperature of 20 to 40 DEG C satisfying 50 to 100 g / L is immersed for 1 to 10 minutes And electroless plating is performed on the electromagnetic shielding coating method.

The present invention is characterized in that the second plating process is an ammonium tungstate hydrate ((NH ₄ ) ₁₀ (H ₂ W ₁₂ O ₄₂ ) .4H ₂ ) having a pH of 6 to 8 and a concentration of 20 to 60 g / O) solution by immersing the surface of the material having the first plating layer formed thereon for 10 to 50 minutes to perform electroless plating.

Particularly, the present invention provides an electromagnetic shielding coating method wherein the metal or non-metal material is selected from the group consisting of carbon fiber and EMC (Epoxy Mold Compound) in a semiconductor chip packaging process. Specifically, the metal or non- A device, a smart car, a smart phone, a communication device, and components constituting a notebook.

The present invention relates to an electromagnetic shielding coating method wherein the metal or nonmetal material is an EMC (Epoxy Mold Compound) of a carbon fiber or semiconductor chip packaging process constituting a wearable device when the metal contained in the seed layer is Pd (palladium) .

On the other hand, when the metal included in the seed layer is Ni (nickel) and Fe (iron), the metal or non-metal material provides one of the components constituting a smart automobile.

As described above, the electromagnetic shielding coating method of the present invention can form a fine coating on parts such as a semiconductor chip of an electronic device, and can form a coating layer with uniform thickness on the entire surface of electronic parts, And has excellent electromagnetic shielding performance.

Furthermore, since the coating layer has excellent adhesion at the surface of the coating material, the coating layer is not separated from the surface of the material even under the conditions of moisture and high temperature, so that the lifetime of the coating layer is long and the adhesion of the coating layer is excellent.

Particularly, since the coating material and the coating layer are in close contact with each other without voids or defects, the coating layer can be maintained in a close contact state without being deformed even in an environment exposed to moisture or heat, .

Compared to the prior art in which rare metals are used or cases outside the electronic device are used, there is an advantage in that the production efficiency is increased as the time for forming a plating layer is remarkably shortened by using a low-cost metal.

It is possible to directly apply the electromagnetic wave shielding function to the component parts of the smart car which can secure the electromagnetic wave shielding function effectively in the ultra-small parts and the wearable devices and which is highly dangerous due to the malfunction, There is an advantage that various applications can be applied to electronic devices which are gradually reduced in size and weight.

1 is a flow chart of the process of the electromagnetic shielding coating method of the present invention;
2 is a vertical sectional view of an electromagnetic wave shielding layer according to an electromagnetic wave shielding coating method according to the present invention;
3 is a photograph showing before and after the formation of the EMC mold and the electromagnetic wave shielding coating layer on the semiconductor chip.

Hereinafter, each configuration will be described in more detail, but this is only an example, and the scope of the present invention is not limited by the following contents.

As described above, in the present invention, a plating layer is formed on the surface by adding a reducing agent in a state in which the coating material is immersed in a solution in which metal ions are dissolved so that a metal plating layer can be formed on the surface of the metal or nonmetal material.

The electromagnetic wave shielding coating method according to the electroless plating method according to the present invention may be sodium hypophosphite (NaH ₂ PO ₂ ), boron hydride compound or hydrazine compound as a reducing agent.

Specifically, the borohydride compound may be reduced to a hydrogenation having a reducing property such as sodium borohydride (NaBH ₄ ), dimethylamine borane ((CH ₃ ) ₂ HNBH ₃ ), diethylamine borane ((CH ₃ CH ₂ ) ₂ HNBH ₃ ) Any of the boron compounds can be used, and the hydrazine compound can be used as a reducing agent such as hydrazine (NH ₂ NH ₂ ), hydrazine sulfate (NH ₂ NH ₂ .H ₂ SO ₄ ), hydrazine hydrochloride (NH ₂ NH ₂ .2HCl) Any hydrazine compound can be used.

In the electromagnetic wave shielding coating method according to the present invention, the material of the coating material to be coated may be a metal or a non-metal, and specifically, it may be applied without limitation of materials as long as electroless plating can be applied. For example, it may be at least one selected from the group consisting of carbon fiber and EMC (Epoxy Mold Compound) in a semiconductor chip packaging process.

Further, the electromagnetic wave shielding coating method according to the present invention is applied to electronic devices, and is intended to shield unnecessary electromagnetic waves emitted from electronic devices, and is applicable to the components of all electronic devices. Particularly, the electromagnetic wave shielding coating method according to the present invention is not limited to a coating material of a metal material but can be applied to a plastic, a silicon wafer and a polymer mold. The coating method can be applied to constituent parts of an electronic device having a microstructure . Specifically, it may be one selected from the components constituting a wearable device, a smart car, a smart phone, a communication device, and a notebook, and various applications are possible within a range where the electronic device does not hinder operation.

The electromagnetic shielding coating method according to the present invention can reduce the waste of unnecessary space in the electronic device by forming a coating layer on the surface of the electronic device parts, unlike the conventional method of introducing a case for enclosing the electronic parts, As electronic devices become smaller and lighter, they can be applied to a wide variety of technical fields.

In the electromagnetic wave shielding coating method of the present invention, the pretreatment process for cleaning the surface of the material and dry-etching the surface before coating is to remove contaminants such as oxides, hydroxides, metal salts and oils adhered to the surface of the coating material to be coated .

First, surface cleaning is performed to remove contaminants. After the contaminants physically adhered to the surface are first removed through a vacuum cleaner or a dry etching process, an alkaline, organic solvent, emulsion, and acid solution And degreasing the surface of the workpiece. It is necessary to appropriately select and use it according to the type of contaminant, and to appropriately select and degrease it so as not to damage the surface of the material.

It is necessary to form a metal seed layer on the surface of the pre-processed material so that the adhesion between the plating layer and the surface of the material can be further improved before forming the plating layer.

The metal constituting the seed layer may be at least one selected from the group consisting of Pd (palladium), Ni (nickel), and Fe (iron). Depending on the kind of the material or the thickness of the plating layer, Can be selected.

When the metal contained in the seed layer is Pd (palladium), the surface seed substitution is performed in a palladium sulfate (PdSO ₄ ) solution having a pH of 7 to 9 and a concentration of 5 to 20 g / For 1 to 10 minutes so as to be electroless-plated.

The temperature of the electroless plating solution may be preferably from 40 to 70 캜, and most preferably from 50 to 60 캜.

When the coating is performed at a temperature higher than the above-mentioned temperature range, there is a problem that a coating layer having a uniform thickness is not formed on the surface of the coating material, and a part of the swollen coating layer can be formed. There is a drawback that the coating layer is not formed on the entire surface of the coating material.

On the other hand, when the metal contained in the seed layer in the surface seed substitution formation process is Ni (nickel) and Fe (iron), at a temperature of 150 to 250 ° C. and a degree of vacuum of 10 ^-5 to 10 ^-3 mmHg, And then performing metal plasma sputter coating on the surface of the workpiece for 1 to 15 minutes.

The temperature conditions may preferably be from 170 to 225 캜, and most preferably from 180 to 200 캜.

There is a problem that the density of the seed layer is lowered at a temperature higher than the above temperature, and the adhesion between the plating layer and the material is inferior. In the case where the temperature is lower than the above temperature, the formation of the seed layer takes a long time.

The thickness of the seed layer may be 0.05 to 5 탆 (micrometer), preferably 0.12 to 3 탆 (micrometer), and most preferably 0.2 to 1 탆 (micrometer).

The role of the seed layer is to pretreat the surface of the metal or non-metal material, to suppress the reduction of unnecessary metal ions in the solution to be subjected to the electroless plating, to reduce the metal ion only on the surface of the seed layer, .

After the seed layer is formed, an electromagnetic wave shielding coating layer is formed through a first plating process and a second plating process.

The thickness of the first plating layer formed through the first plating process may be 0.05 to 5 탆 (micrometer), preferably 0.08 to 3 탆 (micrometer), and most preferably 0.1 to 1 탆 (Micrometer).

The thickness of the second plating layer formed through the second plating process may be 1 to 10 탆 (micrometer), preferably 1.5 to 7 탆 (micrometer), and most preferably 2 to 5 탆 (Micrometer).

By forming the first plating layer and the second plating layer having a predetermined thickness as described above, it is possible to shield electromagnetic waves having a wide bandwidth, thereby achieving a high electromagnetic wave shielding effect. In addition, if the thickness of the first plating layer is less than the thickness of the first plating layer, the first plating layer may not be formed to have a uniform thickness, which may result in formation of a plating layer having a less uniform thickness at the time of forming the second plating layer.

Particularly, when the thickness is thinner than the above thickness, there is a problem that the electromagnetic wave shielding effect is not sufficient and the electromagnetic wave of low frequency is not blocked. If the thickness is thicker than the thickness, it takes a longer time than necessary to form the thickness, thereby reducing the process efficiency and forming a thick layer unnecessarily unnecessary even though the sufficient effect of blocking the electric wave in the thickness range can be obtained. Is most preferable in terms of process efficiency, manufacturing cost, and electromagnetic shielding effect.

The first plating process may be performed by immersing the surface of a material having a seed layer formed thereon in a copper chloride solution having a pH of 8 to 10 and a concentration of 50 to 100 g / L satisfying 20 to 40 캜 for 1 to 10 minutes to perform electroless plating Lt; / RTI >

Preferably, the pH may be 8.5 to 9.5 and may be performed at 25 to 35 占 폚. The kind of the compound is not particularly limited as far as it contains copper ion, but a solution in which copper chloride is dissolved in water can be used.

When the above conditions are satisfied, it is possible to obtain the thickness of the first plating layer at a level of 0.05 to 5 mu m (micrometer) during the immersion time within 10 minutes, and if the plating is performed at a higher temperature, There is a problem that a porous layer is formed which can be also confirmed. In the case of performing at a lower temperature, it is possible to form the plating layer with the thickness only when the immersion time is longer. Particularly, if the coating material is immersed in the aqueous solution for 10 minutes or more in the first plating process, the surface of the first plating layer is not uniform and is formed into a rough layer. Therefore, even after forming the second plating layer, It is important to form the first plating layer by immersing in the above conditions within 10 minutes because there is a problem of forming an uneven outer surface.

The second plating process is a solution of ammonium tungstate hydrate ((NH ₄ ) ₁₀ (H ₂ W ₁₂ O ₄₂ ) .4H ₂ O) having a pH of 6 to 8 and a temperature of 20 to 60 g / The surface of the material having the first plating layer formed thereon may be immersed for 10 to 50 minutes for electroless plating.

Preferably at a pH of 6.8 to 7.8 and at a temperature of 72 to 78 ° C. The type of compound is not particularly limited as long as it contains tungsten ions, but it may preferably be a solution of ammonium tungstate hydrate ((NH ₄ ) ₁₀ (H ₂ W ₁₂ O ₄₂ ) .4H ₂ O).

Particularly, when the coating is performed at a temperature higher than the above-mentioned condition in the second plating process, bubbles are formed on the coated surface to form a non-uniform coating layer. If the coating is performed at a temperature lower than the above condition, There is a problem that a thick coating layer is formed only on a part of the surface. Furthermore, when the plating is performed at a temperature higher than the above-mentioned temperature in the second plating process, the vertical cross section of the entire coating layer is formed into a large inclined shape, resulting in product defects.

The electromagnetic shielding coating method according to the present invention has an advantage that a coating layer can be formed on a metal or a non-metal material, and particularly, it can be applied to materials such as carbon fiber and EMC (Epoxy Mold Compound) .

Specifically, the coating layer is formed on the surfaces of the components constituting the wearable device, the smart car, the smart phone, the communication device, and the notebook. The metal or the non-metal material may be a carbon fiber or a semiconductor chip packaging process An electromagnetic shielding coating layer can be formed by forming a seed layer containing Pd (palladium) in an EMC (Epoxy Mold Compound), and then sequentially forming a first plating layer and a second plating layer.

On the other hand, a seed layer containing Ni (nickel) and Fe (iron) is formed on the components constituting the smart vehicle, and then the first and second plating layers are sequentially formed to form an electromagnetic wave shielding coating layer.

1 is a flowchart illustrating a process of an electromagnetic shielding coating method according to the present invention. The method includes a preprocessing step (S100) of cleaning the surface of the workpiece and etching the surface of the workpiece before coating, And a surface seed substitution formation process (S300) for forming a metal seed layer on the substrate. Since the electromagnetic shielding coating method according to the present invention differs in the method of forming the seed layer depending on the material of the coating material, it is possible to further include a step (S200) of determining the material of the coating material prior to the surface seed substitution formation process have. When a carbon fiber or a semiconductor chip is to be coated, a seed layer can be formed through electroless plating (S300). When a chip for a smart car is to be coated, a seed layer can be formed (S300 ') by sputtering have. After the seed layer is formed, the first plating process (S400) and the second plating process (S500) may be sequentially performed to form an electromagnetic wave shielding coating layer suitable for the characteristics and use of the coating material.

FIG. 2 is a vertical cross-sectional view of an electromagnetic wave shielding layer according to the present invention, in which a seed layer 20, a first plating layer 30, and a second plating layer 40 are sequentially formed on a surface of a coating material 10 The structure of the coating layer laminated on the substrate was shown.

Hereinafter, the present invention will be described in more detail by way of examples, but the scope of the present invention is not limited thereto.

Manufacturing example

≪ Example 1 >

The surface of the semiconductor chip was maintained at a temperature of about 180 캜 at a degree of vacuum of 10 ^-5 to 10 ^-3 H Hg, and the surface of the material was etched with CF ₄ gas after irradiating the surface plasma with 99% oxygen gas.

The surface of the semiconductor chip subjected to the above process was placed in an aqueous solution of palladium sulfate (PdSO ₄ ) having a concentration of 7 g / L at 55 ° C, and an aqueous solution of sodium hypophosphite (NaH ₂ PO ₂ ) was added thereto so as to have a concentration of 3 g / Followed by immersion for 8 minutes to form a seed layer.

Taken out of the semiconductor chip 30 ℃, 80 g / L concentration is placed in a copper chloride aqueous solution of sodium hypophosphite (NaH ₂ PO ₂₎ was immersed 5 minutes after addition of the solution, followed by 75 ℃, 40 g / L of tungstic acid Was immersed in an aqueous solution of ammonium hydrate ((NH ₄ ) ₁₀ (H ₂ W ₁₂ O ₄₂ ) .4H ₂ O) for 30 minutes to form an electromagnetic wave shielding coating layer.

≪ Example 2 >

An electromagnetic wave shielding coating layer was formed in the same manner as in Example 1, except that the surface of a 10 * 10 cm ² carbon fiber fabric woven with carbon fibers was used instead of a semiconductor chip. The carbon fiber fabric with the coating layer formed was entirely wrapped around the surface of the semiconductor chip to fabricate the semiconductor packaging.

≪ Example 3 >

The surface of the semiconductor chip for a smart automobile was maintained at a temperature of about 180 ° C. and a degree of vacuum of 10 ^-5 to 10 ^-3 mmHg, and the surface plasma was irradiated with 99% oxygen gas.

The surface of the plasma-treated material was subjected to a plasma sputtering process using nickel and iron as target materials under conditions of a temperature of 195 ° C. and a degree of vacuum of 10 ^-5 to 10 ^-3 mmHg at a rate of 1.5 kW Respectively. The Smart Car semiconductor chips 30 ℃, 80 g / L concentration is placed in a copper chloride aqueous solution, followed by the addition of sodium hypophosphite (NaH ₂ PO ₂₎ solution was immersed 5 minutes and, after 75 ℃, 40 g / L (NH ₄ ) ₁₀ (H ₂ W ₁₂ O ₄₂ ) .4H ₂ O) aqueous solution of ammonium tungstate for 30 minutes to form an electromagnetic wave shielding coating layer.

≪ Comparative Example 1 &

An electromagnetic wave shielding coating layer was formed in the same manner as in Example 1, except that a seed layer was formed on the surface of the semiconductor chip with a conductive polymer instead of immersing in an aqueous solution of palladium sulfate.

≪ Comparative Example 2 &

An electromagnetic wave shielding coating layer was formed in the same manner as in Comparative Example 1, except that the surface treatment by a sandblast process was performed instead of immersing in an aqueous solution of palladium sulfate.

≪ Comparative Example 3 &

The copper thin film was bonded to the surface of the semiconductor chip using an epoxy adhesive, and then heat treated to oxidize the copper thin film to form an electromagnetic wave shielding coating layer.

≪ Comparative Example 4 &

75 ℃, 40 g / L of tungstic acid, ammonium hydrate in the same manner as in Example 1, except _{((NH 4) 10 (H} 2 W 12 O 42) · 4H 2 O) was used to form an aqueous solution kept at 90 ℃ instead of the aqueous solution ≪ / RTI >

≪ Comparative Example 5 &

75 ℃, 40 g / L of tungstic acid, ammonium hydrate _{((NH 4) 10 (H} 2 W 12 O 42) · 4H 2 O) in the same manner as in Example 1 except that instead of using an aqueous solution kept at 65 ℃ solution ≪ / RTI >

≪ Comparative Example 6 >

75 ℃, 40 g / L of tungstic acid, ammonium hydrate in the same manner as in Example 3, except _{((NH 4) 10 (H} 2 W 12 O 42) · 4H 2 O) that instead of using an aqueous solution kept at 90 ℃ solution ≪ / RTI >

≪ Comparative Example 7 &

75 ℃, 40 g / L of tungstic acid, ammonium hydrate _{((NH 4) 10 (H} 2 W 12 O 42) · 4H 2 O) in the same manner as in Example 1 except that instead of using an aqueous solution kept at 65 ℃ solution ≪ / RTI >

≪ Comparative Example 8 >

75 ℃, 40 g / L of tungstic acid, ammonium hydrate _{((NH 4) 10 (H} 2 W 12 O 42) · 4H 2 O) in the same manner as Example 2, except that instead of using an aqueous solution kept at 90 ℃ solution ≪ / RTI >

≪ Comparative Example 9 &

75 ℃, 40 g / L of tungstic acid, ammonium hydrate _{((NH 4) 10 (H} 2 W 12 O 42) · 4H 2 O) in the same manner as Example 2, except that instead of using an aqueous solution kept at 65 ℃ solution ≪ / RTI >

≪ Reference Example 1 &

A semiconductor chip not subjected to electromagnetic wave shielding treatment was prepared separately.

<Reference Example 2>

A metal can having a thickness of 2 mm made of stainless steel was manufactured and a semiconductor chip package having a structure wrapped around the outer surface of the semiconductor chip was manufactured.

Experimental Example

1. Experiment of coating layer thickness measurement

Using a X-ray diffractometer, the thickness of the thin film was measured 20 times at different portions on the wide surface of the semiconductor chip at the time of forming each metal layer. The average values of the measured thickness values are shown in Table 1, and the standard deviations of the thickness values measured 20 times from the obtained average values are shown in Table 2.

The thickness of the first plating layer was calculated by subtracting the thickness of the seed layer from the thickness of the first plating layer except for the first seed layer on the surface of the coating material. The thickness of the first plating layer, The value obtained by subtracting the thickness of the plating layer was calculated as the thickness of the second plating layer.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 thickness
(탆) Seed layer 0.252 0.187 0.223 - - - The first plating layer 0.341 0.243 0.343 - - - The second plated layer 3.030 3.254 3.147 - - - Total thickness 3.623 3.684 3.713 4.120 5.071 3.924 division Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 thickness
(탆) Seed layer 0.225 0.259 0.192 0.203 0.243 0.200 The first plating layer 0.410 0.271 0.277 0.232 0.331 0.401 The second plated layer 3.192 3.097 3.221 3.811 2.997 3.267 Total thickness 3.827 3.627 3.690 4.246 3.571 3.868

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Standard
Deviation
(탆) Seed layer 0.0002 0.0003 0.0002 - - - The first plating layer 0.0005 0.0011 0.0024 - - - The second plated layer 0.5423 0.9432 1.2325 - - - division Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Standard
Deviation
(탆) Seed layer 0.122 0.094 0.142 0.197 0.019 0.044 The first plating layer 0.092 0.135 0.122 0.164 0.112 0.208 The second plated layer 1.221 2.102 1.549 0.947 1.211 0.988

2. Comparison test of electromagnetic shielding ability

Table 3 shows the values obtained by comparing the electromagnetic shielding ability of the examples, the comparative examples and the reference examples.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Reference Example 1 Reference Example 2 frequency
(MHz) 30 to 1000 100-300 100-500 - 100-1000 Shielding
effect
(dB, min to max) 85 to 107 89-100 90-110 60 to 70 80-100 30-60 - 60 to 70

3. Experiment to measure adhesion of coating layer

Table 4 shows the specimens of Examples and Comparative Examples by observing the change of the coating layer after tape test and thermal shock were applied.

Example 2 Comparative Example 8 Comparative Example 9 Tape test X O O Thermal shock test △ O O

(O: deformation severity,?: Partially deformed, X: no change)

4. Process speed measurement experiment

The time required for completing the formation of the electromagnetic wave shielding coating layer of one semiconductor chip according to Example 1, Comparative Examples 1 to 3, and Reference Example 2 was measured and shown in Table 5.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Manufacturing time
(Minutes / 1000) 50 150 200 160

5. Comparison of Volume of Semiconductor Package

The volume of the semiconductor package after completion of the tar wave shielding coating of Example 1, Comparative Examples 1 to 3, and Reference Example 2 was measured and the values compared with the volume of Reference Example 1 are shown in Table 6.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Reference Example 1 Reference Example 2 Reference Example 1
Contrast ratio
(%) 122% 134% 141% 125% 100% 230%

Referring to Experimental Example 1, it can be seen that the thicknesses of the entire coating layers in Examples and Comparative Examples were formed to be generally the same level. However, in the standard deviation, it can be seen that the coating layer of the embodiment has a small standard deviation value in the seed layer, the first plating layer and the second plating layer, so that a uniform coating layer is formed on the coated front surface. On the contrary, the comparative example has a relatively large standard deviation value, and it is confirmed that a coating layer of uniform thickness is not formed even though the measurement results are obtained at a limited number of times of 20 times.

It was confirmed that the electromagnetic wave shielding effect of Comparative Examples 1 to 3 was not so large as shown in Table 3 of Experimental Example 2 although the thickness was slightly thicker than those of Examples. Since electronic devices are miniaturized and used frequently in close proximity to the human body, development of wearable devices that are worn directly on the human body, and in addition, electronic devices that are inserted into the human body will be actively developed. It is absolutely necessary to improve not only the thickness of the electromagnetic wave shielding coating but also the electromagnetic wave shielding performance.

The electromagnetic wave shielding coating according to the embodiment has an electromagnetic wave shielding effect in a very wide area and is excellent in shielding effect and is expected to be used in an electronic device to be inserted into a human body. It was confirmed that the embodiments 1 to 3 can block electromagnetic waves in all areas at almost perfect level because the range of 30-1000 MHz is blocked. At present, the electromagnetic shielding effect is considered to be almost 100% shielding area at 90-120 dB, which shows the highest electromagnetic wave shielding effect at the present technology level.

In the case of Comparative Examples 4 to 7, similar shielding effect was exhibited. However, as described later, there is a disadvantage in that a coating layer completely close to the edge of the coated material is not formed. .

Particularly, in the case of Comparative Examples 4 and 7, further experiments were carried out to peel off the coating layer of the coating material, and it was confirmed that the coating layer was easily peeled off from the edge portion, especially in the coating layer.

In contrast, in Examples 1 to 3, peeling off of the coating layer of the coating material was conducted. As a result, it was confirmed that it was difficult to peel off the coating layer from the front surface of the coating material, thereby forming a durable and durable coating layer.

On the other hand, as the pollution problem of air pollution such as fine dust becomes serious, the use of electric vehicles increases and the supply and demand of smart vehicles increase, so that the technology that can more effectively block the electromagnetic wave interference effect inside the automobile The electromagnetic wave shielding coating method according to the present invention is expected to be applicable to various electronic devices in the future because it covers almost a perfect level in a wide range of frequencies of electronic apparatus parts.

In comparison with Comparative Examples 1 to 3, it can be seen that the coating layer of Example 1 was formed to have a uniform thickness, and the coated coating layer was formed without forming a portion apart from the surface of the coating material. Particularly, in the tape test, almost all of the coating layers are separated in the case of Comparative Examples 1 to 3, whereas Example 1 is good.

In the case of Comparative Examples 1 and 3 in the thermal shock test, the spaced space between the coating material and the coating layer swelled and the appearance of the material was severely deformed after thermal shock was applied. Since heat is generated during operation of the electronic device, maintaining excellent heat resistance in a high-capacity electronic device may considerably affect not only the electromagnetic wave shielding effect and its sustainability but also the malfunction of the electronic device itself. .

In Comparative Examples 5 and 7 in which the second plating process was performed at a temperature higher than that in Examples, the coating layer itself was unevenly formed such that a slope was formed in the cross section of the coating layer, which was treated as a bad semiconductor chip, It was confirmed that there was a problem of falling.

Since the electromagnetic shielding coating method according to the present invention can coat 1000 of the process characteristics at the same time, the time required for manufacturing 1000 final products can be completed only by one process, It is found that the process efficiency is excellent in comparison with the conventional process.

In the case of Comparative Examples 1 and 2, the conductive polymer drying process was indispensable and the process time was greatly increased. In the case of Comparative Example 3, the thin film deposition process took a long time to adhere the copper thin film uniformly.

Referring to Experimental Example 5, it can be seen that the volume of the semiconductor package manufactured according to Example 1 is the most similar to that of Reference Example 1 in which electromagnetic wave shielding coating treatment is not performed. Accordingly, it is possible to prevent formation of an unnecessary space of the electronic apparatus, and the present invention can be applied to parts of small and very small electronic apparatuses. In addition, it can be seen that the coated semiconductor chip according to Example 1 can form a coating layer adhered to the microstructure of the semiconductor surface, and the coating layer is formed by the coating material and the coating layer closely contacted with each other. It is applied to parts of various electronic devices to improve the lifetime of the coating layer and to improve the durability of the coating layer.

Claims (10)

A method of shielding electromagnetic wave shielding on a surface of a metal or nonmetal material,
A pretreatment step of cleaning the surface of the material and etching the dry surface before coating;
A surface seed substitution formation process for forming a metal seed layer on the pretreated surface;
A first plating step of performing electroless plating of a basic shielding function with a first metal on the seed layer surface; And
A second plating step of performing electroless plating of a second metal having a finishing shielding function on the surface of the first metal plating layer;
/ RTI &gt;
Wherein the first metal is Cu (copper), the second metal is W (tungsten)
The first plating process may include:
the surface of the material having the seed layer formed thereon is immersed for 1 to 10 minutes in a copper chloride (CuCl ₂ ) solution having a pH of 8 to 10 and a concentration of 50 to 100 g / L satisfying 20 to 40 ° C,
The second plating process may include:
a first plating layer is formed in a solution of ammonium tungstate hydrate ((NH ₄ ) ₁₀ (H ₂ W ₁₂ O ₄₂ ) .4H ₂ O) having a pH of 6 to 8 and a concentration of 20 to 60 g / The surface of the material is immersed for 10 to 50 minutes to perform electroless plating,
The surface seed substitution formation process includes:
The metals included in the seed layer are Ni (nickel) and Fe (iron)
Characterized in that a metal plasma sputter coating is applied to the surface of the material for 1 to 15 minutes at a temperature of 150 to 250 캜 and a degree of vacuum of 10 ^-5 to 10 ^-3 mm Hg. The method according to claim 1,
Wherein the thickness of the first plating layer formed through the first plating process is 0.05 to 5 占 퐉 (micrometer). The method according to claim 1,
Wherein the thickness of the second plating layer formed through the second plating process is 1 to 10 占 퐉 (micrometer). The method according to claim 1,
Wherein the seed layer has a thickness of 0.05 to 5 mu m (micrometer). delete delete The method according to claim 1,
Wherein the metallic or non-metallic material is selected from the group consisting of carbon fiber and EMC (Epoxy Mold Compound) in semiconductor chip packaging process. The method according to claim 1,
Wherein the metallic or non-metallic material is one selected from the components constituting a wearable device, a smart car, a smart phone, a communication device, and a notebook computer. delete The method according to claim 1,
Wherein the metallic or non-metallic material is one of the constituent parts constituting a smart automobile.

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