KR20170061096A - Method and apparatus for separating silver from etching waste solution - Google Patents

Abstract

The present invention relates to an apparatus and a method for depositing silver (Ag) from an etching waste solution subjected to an etching reaction in which an object to be etched is decomposed by an etching solution.
By precipitating silver ions dissolved in the etching waste solution through the silver precipitation apparatus of the present invention and the silver precipitation method through the apparatus, it is possible to reduce the incidence of defects that may occur when the silver is recycled and adsorbed during the etching process, Effect.

Description

TECHNICAL FIELD The present invention relates to an apparatus and a method for precipitating silver from an etchant waste liquid,

The present invention relates to a technique for depositing silver from an etchant waste solution produced through an etching reaction in which an object to be etched is decomposed by an etchant.

More particularly, the present invention relates to a method for manufacturing a multilayer film comprising a single film made of silver or silver alloy, a multi-layer film made of a transparent conductive metal such as ITO (Indium Tin Oxide) and IZO (Indium Zinc Oxide) And more particularly to an apparatus and a method for depositing silver from an etching waste solution after etching of a transparent electrode / silver / transparent electrode triple film.

2. Description of the Related Art A liquid crystal display (LCD) is one of the most widely used flat panel displays (FPDs), and is composed of two substrates on which electrodes are formed and a liquid crystal layer interposed therebetween, And the liquid crystal molecules in the liquid crystal layer are rearranged by applying a voltage to adjust the amount of transmitted light.

In the liquid crystal display device, a form in which a plurality of pixel electrodes are arranged in a matrix form on one substrate, and electric field generating electrodes are provided on two substrates in which one common electrode covers the entire surface of the substrate. In such a liquid crystal display, image display is performed by applying a separate voltage to each pixel electrode. A gate line for controlling a thin film transistor for switching a voltage applied to each pixel electrode and a gate line A data line is formed on the substrate.

Since the liquid crystal display device is a current injection type element device, the power consumption largely depends on the resistance of the electrode line. If the resistance of the electrode line is high, a large voltage drop occurs due to the flow current, resulting in an uneven luminance, which degrades the display quality.

However, as the liquid crystal display device becomes larger and larger, the lengths of the gate lines and the data lines become longer, and the resistance of the lines gradually increases. Thus, the chromium was mainly used conventionally (Cr: resistivity of 12.7 × 10 ^-8 Ωm), molybdenum (Mo: resistivity of 5 × 10 ^-8 Ωm), aluminum (Al: Resistivity 2.65 × 10 ^-8 Ωm), and the alloys thereof The continued use of the wiring serves as a cause of making it difficult to realize a large-sized display device and high resolution.

Therefore, as the density and the size of the integrated circuit and the display device are increased, the width of the conductive wiring on the printed circuit board and the display panel substrate is continuously narrowed, and the wiring material and the electrode are required to have low resistance. In order to solve the problem of delay and the like, it is necessary to form the wiring such as the gate line and the data line with a material having the lowest possible resistivity.

In addition, since the transparent electrode made of a conductive metal such as indium tin oxide (ITO) and indium zinc oxide (IZO) has a relatively high transmittance to light and conductivity, it is used for a flat panel display In addition, these transparent electrodes also have a high sheet resistance, which is an obstacle to the enlargement of the flat panel display device through the improvement of the response speed and realization of high resolution.

In order to compensate for this, an auxiliary metal line having a small resistance value is used as an auxiliary electrode in the wiring between the transparent electrodes in the display panel region to reduce the resistance. That is, an electrode is patterned and laminated on a substrate, a metal line is patterned and laminated thereon, then an organic material layer made of an organic compound and a barrier rib are patterned and laminated, and the counter electrodes are laminated, And each of the cathode and the anode is formed so as to be connected to the external terminal. However, this may also cause a problem of lowering the resistance depending on the auxiliary electrode material.

Therefore, a multi-layer film including a silver (Ag: specific resistance: about 1.59 x 10 < ^-8 > OMEGA) film, a silver alloy film or a silver film or a silver alloy film having a low resistivity and a high luminance as compared with metals applied to conventional flat panel displays, Electrode, LCD wiring, and reflector to make the flat panel display large-sized, high resolution, and low power consumption.

However, silver (Ag) is extremely poor in adhesion to an insulating substrate such as glass or a lower substrate such as a semiconductor substrate made of intrinsic amorphous silicon or doped amorphous silicon or the like, lifting or peeling is easily induced. Further, even when a silver (Ag) conductive layer is deposited on a substrate, when etching is performed to pattern it, the side etching length of the silver metal (the degree of loss of metal to be left under the photoresist) is large, silver is excessively etched, Unevenly etched to cause lifting or peeling of the wiring, resulting in poor wiring profile. In addition, if the surface layer of silver that is excessively etched is exposed, silver may be removed from the surface of the substrate by heat treatment in the subsequent process, and the silver may be re-adsorbed. Therefore, in the case of using silver as the wiring, it is required to develop the technique of the etching solution and the etching method in order to reduce the defective rate in the etching process.

Wet etching is a method in which a wafer is put in an etchant of a liquid having a property of dissolving only a target metal in a corrosive manner and etching is performed by a liquid-solid chemical reaction. It is used in fields such as wet etching of metal film in manufacturing process, manufacture of printed wiring board, manufacture of metal name plate, and manufacture of semiconductor device.

As a wet etching treatment method, it is easy to dip in an etchant-filled container. However, it is necessary to shake or mix chemicals in a container to flow a drug that has dissolved and dissolve the metal to supply fresh chemicals to the treated surface. There is a spray type in which these parts are improved and a chemical is sprayed to the object to be treated, a spin type in which a substrate is placed on a rotating table called a spinner, and a chemical is wetted.

However, wet etching can cause problems through chemical reactions in which the film to be etched is not directly dissolved in most etchants but is converted into liquid or gaseous products and removed. If a gaseous product is formed, microbubbles adhere to the microstructure to interfere with the etching, and even if a liquid product is generated, the etching rate is slowed down depending on the concentration of the etched film composition dissolved in the etching solution. There is a problem in the control of the process. Also, depending on the concentration of the film composition dissolved in the etching waste solution, defects due to recycle and adsorption may occur.

Korean Patent No. 0264446 (Reuse Method of Etching Waste Liquid) Korean Patent No. 0579421 (silver etchant composition)

An object of the present invention is to provide an apparatus for depositing silver from an etchant waste solution in order to minimize the incidence of defects that may be caused by silver (Ag) ions being recycled and adsorbed in the manufacture of a display device using silver of low resistivity.

It is another object of the present invention to provide a method of precipitating silver from the etchant waste solution.

According to a preferred embodiment of the present invention, there is provided a lithographic apparatus comprising: a calcination tank filled with an etchant waste solution containing silver; A first deposition electrode and a second deposition electrode arranged opposite to each other; And a rectifier that connects the first deposition electrode and the second deposition electrode and applies a current to the first deposition electrode.

The first deposition electrode may be a cathode, and the second deposition electrode may be an anode.

The first deposition electrode and the second deposition electrode may be made of a metal insoluble in the etching waste solution.

The first deposition electrode may be any one selected from the group consisting of Pt, Ir, Au, Al, Ag, and alloys thereof.

The second deposition electrode may be any one selected from the group consisting of Pt, Ir, Au, and alloys thereof.

Wherein the etchant solution comprises a) from 1 to 20% by weight of hydrogen peroxide, from 0.1 to 4% by weight of a pH adjusting agent, from 0.1 to 5% by weight of a chelating agent, from 0.01 to 3% by weight of a cyclic amine compound and from 72 to 98.79% B) from 1 to 10% by weight of nitric acid, from 50 to 75% by weight of phosphoric acid, from 1 to 20% by weight of acetic acid, from 0.5 to 3% by weight of an auxiliary oxide solubilizer based on the total weight of the composition, 0.001 to 0.01% by weight of an activator, and water to make the total weight of the entire composition 100% by weight.

According to another preferred embodiment of the present invention, an etching solution is used to etch a substrate comprising a single film of silver, a single film of silver alloy, and a single metal film selected from the group consisting of silver and a multi- step; Transferring the etching waste solution generated in the etching reaction to the silver (Ag) precipitation tank through the etching waste solution transfer device; Connecting the first deposition electrode and the second deposition electrode to the silver deposition tank; And a step of applying current to the first deposition electrode and the second deposition electrode to deposit silver (Ag) in the etching waste solution.

The current applied to the first deposition electrode and the second deposition electrode may be in the range of 0.1 to 8.5 A and the voltage may be in the range of 1 to 5 V. [

The present invention provides an apparatus and method for depositing silver from an etchant waste solution, and has the effect of reducing the incidence of defects that can occur due to silver recycle and adsorption during the wet etching process by precipitating silver dissolved in the etchant waste solution.

Further, the present invention provides an apparatus and method for recovering silver from an etchant waste solution, thereby increasing the number of etch treatments.

1 is a schematic diagram showing an apparatus for depositing silver from an etchant waste solution according to an embodiment of the present invention.
2 is a schematic view of an etching apparatus and an apparatus for depositing silver from an etching waste solution according to another embodiment of the present invention.
3A is a schematic view of a film to be etched which is described in an embodiment of the present invention.
FIG. 3B is a schematic view of a film at an intermediate etching stage described in an embodiment of the present invention. FIG.
3C is a schematic diagram of the etched film described in one embodiment of the present invention.
4A and 4B are photographic images of the surface of the electrode on which silver is deposited during the collecting evaluation according to the first embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. It should be understood that the terms " comprises " or " having ", and the like in the description of the present invention are intended to specify the presence of stated features, integers, But do not preclude the presence or addition of features, numbers, steps, operations, configurations, elements, components, or combinations thereof.

The present invention relates to a technique for depositing silver (Ag) from an etchant after an etching reaction in which an etchant is decomposed by an etchant, more preferably a single layer of silver or silver alloy, silver and ITO (Indium Tin Oxide ), And IZO (Indium Zinc Oxide), and a composite film including other metals in the multi-film, particularly a transparent electrode / silver / transparent electrode. Apparatus and method.

An apparatus for depositing silver from an etching waste liquid according to an embodiment of the present invention includes: a deposition tank filled with an etchant waste solution containing silver; a first deposition electrode and a second deposition electrode arranged opposite to each other; And a rectifier connecting the electrode and the second deposition electrode to apply a current.

FIG. 1 is a schematic view showing an apparatus for depositing silver from an etching waste solution according to an embodiment of the present invention, FIG. 2 is a schematic view of an etching apparatus and an apparatus for depositing silver from an etching waste solution according to another embodiment of the present invention . Hereinafter, an apparatus for depositing silver from an etching waste solution will be described with reference to FIGS. 1 and 2. FIG.

1, the silver (Ag) precipitation apparatus 6 includes a silver (Ag) precipitation tank 5, an etching waste liquid 4 carried on the silver precipitation tank 5, An electrode 1, a second precipitation electrode 2, and a rectifier 3. [0028]

More specifically, the silver (Ag) precipitation apparatus 6 is provided with a first deposition electrode 1 and a second deposition electrode 2 facing each other in a silver (Ag) deposition tank 5, A rectifier (3) is connected to the two electrodes (1, 2).

According to an embodiment of the present invention, the first deposition electrode 1 may be a cathode and the second deposition electrode 2 may be an anode. It is preferable that a metal having a stronger reducing power than the second deposition electrode 2 is used for the first deposition electrode 1 to be the cathode and that the first deposition electrode 1 and the second deposition electrode 2 The electrode (2) may be made of a metal insoluble in the etching waste liquid (4). The first deposition electrode 1 may be made of Pt, Ir, Au, Al, Ag, or an alloy thereof. The second deposition electrode 2 may be formed of Pt, Ir, Au, And alloys thereof, and the like.

The current applied to the rectifier 3 can be adjusted in the range of 0.1 to 8.5 A, and the voltage can be selected in the range of 1 to 5 V. [ The current range is more preferably in the range of 2 to 7 A, and more preferably in the range of 2.5 to 6.5 A. The voltage range may be more preferably in the range of 1.5 to 4.5 V, and even more preferably in the range of 2 to 4 V. If the current range is less than 0.1 A, the etching reaction in the etching waste solution predominates and the problem of non-precipitation of the metal may occur. If the current range exceeds 8.5 A, the etching solution decomposes at the deposition electrode, Lt; / RTI > If the voltage range is less than 1 V, the etching reaction in the etching waste solution may predominate and the metal may not be precipitated. If the voltage exceeds 5 V, the etching solution may decompose at the deposition electrode, May cause problems.

The etching waste liquid 4 may have a composition similar to that of the etchant causing the etching reaction in the etching bath 7 of FIG. 3, but the composition of the etched film dissolved in the etching reaction may be further added. In addition, a reducing agent may be further added to the etching waste solution 4 to promote the reduction reaction of silver (Ag) selectively. The reducing agent may be selected from a liquid composition such as hydrazine, hydroperoxide, formalin, oxalic acid and the like or a vapor composition such as hydrogen (H ₂ ) and carbon monoxide (CO) gas .

The etchant is a medium that causes a chemical reaction to a material to be etched and corrodes to cut off a specific area. As an example of the etchant, a liquid acid or a liquid base and an electrolytic solution of an acid, a base or a salt thereof may be contained. In particular, an organic acid, an inorganic acid, a Lewis acid, a Lewis base or a solution thereof may be preferably used as an electrolytic solution . More specifically, as the constitution of the etchant, an appropriate material may be selected according to the material of the part to be etched of the metal etch film 14 to be etched. For example, an aqueous solution of hydrofluoric acid, phosphoric acid, sulfuric acid, hydrogen peroxide, hydrochloric acid, potassium hydroxide, sodium chloride, potassium chloride, aluminum chloride, zinc chloride, tin chloride, ferric chloride sodium nitride and potassium nitride, Nitric acid and sulfuric acid, and various liquids including an aqueous solution of the above acids.

Alternatively, another example of the etchant may be selected from nitric acid, phosphoric acid, acetic acid, and hydrogen peroxide which are conventionally used for etching a conventional silver or silver alloy film. In order to improve the etching property for silver, a supplementary oxide dissolver and a surfactant, a pH adjusting agent, a chelating agent, an amine compound, a buffer solution, a sequestering agent, a corrosion inhibitor, water, and a mixture thereof.

Specific examples of the auxiliary oxide dissolving agent include sulfuric acid, ammonium sulfate, calcium sulfate, (CH ₃ ) ₂ SO ₄ , (C ₂ H ₅ ) ₂ SO ₄ , H ₃ NCH ₂ CH ₂ SO ₄ ^2- compounds such as NH ₃ SO ₄ , (NH ₃ OH) ₂ SO ₄ , [N (CH ₃ ) ₄ ] SO ₄ H and [N (C ₂ H ₅ ) ₄ ] SO ₄ H, It may be used compounds ^- ClO _4, such as sodium, potassium perchlorate, barium perchlorate, magnesium perchlorate and lithium perchlorate.

The surfactant and more particularly hambul and the use of small carbon-based surface active agent, the ammonium fluoroalkyl sulfone _{imide, C n F 2n + 1 CH} 2 CH 2 SO 3 - NH 4 +, C n F 2n + 1 CH _{2 CH 2 SO 3 H, (} C n F 2n + 1 CH 2 CH 2 O) x PO (ONH 4 +) y (OCH 2 CH 2 OH) z, C n F 2n + 1 CH 2 CH 2 O (OCH _{2 CH 2 OH) x H,} C n F 2n + 1 SO 2 n (C 2 H 5) (CH 2 CH 2) x H, C n F 2n + 1 CH 2 CH 2 OCH 2 (OH) CH 2 CH _{2 N (C n F 2n +} 1) 2, and _{C n F 2n + 1 CH 2} CH 2 OCH 2 (OCH 2 CH 2) n CH 2 CH 2 N (C n F 2n + 1) 2 [ wherein, n is an integer of 1 to 20, and x, y and z are real numbers satisfying x + y + z = 3].

The pH adjusting agent may be at least one salt compound selected from the group consisting of ammonium salts, sodium salts and potassium salts. Specific examples thereof include ammonium citrate, ammonium acetate, ammonium dihydrogen phosphate, disodium citrate, sodium acetate, sodium Hydrogen phosphate, and the like.

When the silver chelating agent reacts with the silver etching solution, the stability may be lowered. More specifically, examples of the chelating agent include carboxylic acid-based compounds such as acetic acid, glycolic acid, citric acid, oxalic acid, and malonic acid, and a mixture of at least one thereof may be used.

The amine compound serves to control the etching rate of silver, and more preferably, a cyclic amine compound can be used. Specific examples of the amine compound include pyrrolidine, pyrroline, pyrrole, indole, pyrazole, imidazole, pyrimidine, purine and pyridine and derivatives thereof, and a mixture of at least one of them may be used .

The buffer solution serves to control the isotropic etching by anisotropic etching in which the side etching is relatively small by decreasing the etching rate of silver. The buffer solution may be selected from, for example, a 1: 1: 1 aqueous solution of nitric acid: hydrogen chloride: water, a 1: 1: 4 solution of ammonia water: hydrogen peroxide: methanol, an aqueous solution of potassium iodide: iodine: water,

Preferably, in the present invention, as an example of the etchant, 1 to 20% by weight of hydrogen peroxide, 0.1 to 4% by weight of a pH adjusting agent, 0.1 to 5% by weight of a chelating agent, 0.01 to 3% by weight of a cyclic amine compound, And 72 to 98.79% by weight of water.

Another example of the etchant that can be used in the present invention is a composition containing 1 to 10 wt% of nitric acid, 50 to 75 wt% of phosphoric acid, 1 to 20 wt% of acetic acid, 0.5 to 3 wt% of a supplemental oxide solubilizer, From 0.001 to 0.01% by weight of a surfactant, and water so that the total weight of the total composition is 100% by weight.

According to another embodiment of the present invention, the silver (Ag) deposition apparatus 6 is provided with a nozzle 8 for spraying the etching solution in the etching tank 7 as shown in FIG. 2 The etchant is sprayed onto the film 14 to be etched and the etchant is subjected to an etching reaction to form an etchant waste liquid 4. The etchant is sent to the Ag deposition chamber 5 through the etchant waste liquid transfer device 9, The etching apparatus 100 may further include an etch stopper 100. [

A method for depositing silver from an etchant waste solution according to another embodiment of the present invention comprises the steps of: (a) depositing a silver or silver alloy on a substrate comprising multiple films consisting of silver or silver and a transparent conductive metal, (B), the etching waste liquid 4 generated in the etching reaction is transferred from the etching bath 7 to the silver (Ag) bath 5 through the etching waste liquid transfer device 9, (C) connecting the first deposition electrode (1) and the second deposition electrode (2) to the silver deposition chamber (5) and (d) connecting the first deposition electrode And depositing silver (Ag) from the etching waste solution by applying an electric current to the electrode 2 for precipitation.

A method of forming a silver or silver alloy wiring used in the present invention, an etching method, and a method of depositing silver in an etchant waste solution according to another embodiment of the present invention will be described in more detail.

The silver or silver alloy wiring of the present invention can be formed by: 1) laminating a silver or silver alloy conductive layer on the substrate and selectively covering the silver or silver alloy conductive layer and a conductive protective layer having conductivity A deposition process for forming a conductive film, a coating process for coating a photoresist (PR), and a pattern formation process for exposing the photoresist using a photomask of a predetermined pattern and cleaning and developing the photoresist after exposure (4) etching the conductive layer through the pattern, and (5) stripping the photosensitive material layer for pattern development.

2, the etching apparatus 100 includes a silver (Ag) conductive layer 11 formed on the substrate 10, and a conductive layer 11 formed on the etching film 14 including the resist layer 12, An etchant having an etching force with respect to the silver (Ag) conductive layer 11 for performing an etching process and an etchant having an etching force for spraying an etchant used in the etch process, The nozzle 8 and the sprayed etching liquid flow into the silver (Ag) deposition apparatus 6 through the etching waste liquid transfer device 9.

3 is a schematic diagram for explaining the change of the etching film 14 through the etching process occurring in the etching apparatus 100. As shown in FIG. Hereinafter, the etching process will be described with reference to FIGS. 3A to 3C.

The process of etching the silver (Ag) conductive layer 11 through the etching process is shown in detail in FIGS. 3A to 3C. 3A, a silver (Ag) conductive layer 11 is deposited and prepared on the substrate 10 as shown in FIG. 3A, and exposure and development a photoresist (PR) layer 12 having a predetermined pattern is laminated for the purpose of an etching resist to prepare the entire etching film 14.

The etching solution is sprayed from the nozzle 8 of the etching apparatus 100 of FIG. 2 to the silver (Ag) conductive layer 11 on which the photosensitive material layer 12 is formed, and the etching process proceeds. Since the photosensitive material layer 12 has a significantly lower etching rate than the silver (Ag) conductive layer 11 as the metal layer, the silver (Ag) conductive layer 11 exposed without forming the photosensitive material layer 12 ) Portion is removed by the etching liquid, and a circuit pattern as shown in FIG. 3C is formed. The etching process is performed by chemical exchange with a plating material, that is, a silver (Ag) conductive layer 11 by an etching liquid. Accordingly, as the etching progresses, the silver (Ag) conductive layer 11 is gradually etched and the silver (Ag) etching interface 13 is formed thereon, as shown in FIG. 3B. The interfacial surface 13 is restricted by the flow of the Ag (Ag) conductive layer 11 so as not to intermingle with each other. As the circuit pattern becomes denser, the thickness of the interface 13 increases, The movement of the component is limited and it may be difficult to form a fine circuit pattern. In addition, microbubbles may adhere to the microstructure during the chemical reaction of the etchant and the film to be etched at the interface 13, which may interfere with the etching, or may cause defects due to recirculation and adsorption of silver (Ag) ions have.

In the etching tank 7, the etching reaction of the etching film 14 is subsequently performed, and the concentration of the etched silver (Ag) ions in the etching waste solution 4 increases after the etching reaction. Therefore, if such an etching waste liquid 4 is left in the etching bath 7, not only the etching force is reduced but also the wiring formation can be defective due to recirculation and adsorption of silver (Ag) ions.

Therefore, in the present invention, the etching waste liquid 4 having a high silver (Ag) ion concentration is transferred from the etching bath 7 to the silver (Ag) precipitator 6 through the etching waste liquid transfer device 9, As described in the above, the process of precipitating silver was performed to lower the defect occurrence rate and to increase the number of processed panels.

In the silver deposition apparatus 6, a first deposition electrode (1) and a first deposition electrode (2) serving as the cathode as current is applied in the rectifier (3) connected to the second deposition electrode 1), silver (Ag) in the etching waste solution (4) can be reduced and precipitated. The precipitated silver may exist in a form sinking on the surface or the periphery of the first precipitation electrode 1 and the etchant waste solution 4 after the silver precipitation process may be discharged from the silver precipitation tank 5 through a filter have. The etching waste solution 4 after the precipitation process may be recycled to the etching reaction after the process of selectively adding or removing the etching solution composition, but the present invention is not limited thereto.

Therefore, in the present invention, in order to minimize the problem that the silver ions in the interface 13 are recycled or adsorbed, it is necessary to remove the etching waste solution 4 from the etching apparatus 100 to deposit silver (Ag) (6), and a technique of depositing silver from the etching waste liquid (4) has been devised.

Hereinafter, preferred embodiments of the present invention will be described in detail.

In order to simulate the silver etching used in the silver (Ag) etching, the silver etching solution in which 1,000 ppm of the silver powder was dissolved was immersed in the electrolytic bath of 1 L, and the electrolytic collection evaluation was performed by connecting the anode and the cathode to the rectifier. Respectively.

In the electrolytic collection evaluation, one of the cathodes is selected from the group consisting of Pt, Ir, Au, Al and their alloys, more preferably Ir is selected, and Pt, Ir, Au, One of them is selected from the group consisting of these alloys, more preferably Ir is selected and connected.

After immersing the anode and cathode in the prepared silver etching solution, electric current was applied through a rectifier for 5 minutes.

Example 1

Example 1 used an etchant composition comprising 6 wt% nitric acid, 50 wt% phosphoric acid, 15 wt% acetic acid and 100 wt% of the total composition, based on the total weight of the composition. After dissolving 1,000 ppm of silver powder in the etchant, electrodes were connected and a current of 2.5 A was applied to conduct precipitation of silver in the etchant.

4A and 4B are photographic images of the electrode surface on which silver precipitates after the electrolytic collection evaluation as described above is completed.

Example 2

Example 2 was carried out under the condition of Example 1 by changing the applied current condition to 4.5 A.

Example 3

Example 3 was carried out by changing the applied current condition to 6.5 A under the condition of Example 1.

Comparative Example 1

In Comparative Example 1, the experiment was carried out by changing the applied current condition to 0.07 A under the condition of Example 1.

Comparative Example 2

In Comparative Example 2, the experiment was conducted by changing the applied current condition to 9.5 A under the condition of Example 1.

Experiment number The silver (Ag) ion content (ppm) The applied voltage (V) Applied current (A) After the electrolytic collecting, the silver (Ag) ion content (ppm) (Ag) ion trapping amount (ppm) Example 1 1011 2 2.5 923 88 Example 2 1005 3 4.5 885 120 Example 3 1008 4 6.5 863 145 Comparative Example 1 1012 0.5 0.07 1002 10 (etching generation) Comparative Example 2 1015 5.5 9.5 1007 8 (bubble generation)

As can be seen from the results of Table 1, when the current applied to the electrode was 0.07 A as in the silver precipitation process of Comparative Example 1, the etching reaction of silver by the etching solution was faster than the precipitation, so that it was difficult to ensure smooth collection. When the applied current is 9.5 A as in the case of the comparative example 2, the etching solution is decomposed around the electrodes to generate hydrogen and oxygen bubbles, which may interfere with the trapping and may affect the composition of the etchant It was difficult to control the side reaction.

However, as in the results of Examples 1 to 3, the current of the silver deposition collector is in the range of 0.1 to 8.5 A, and when the voltage is in the range of 1 to 5 V, the silver precipitation reaction can proceed effectively as the current and voltage are increased there was.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. And falls within the scope of the present invention.

1: first deposition electrode 2: second deposition electrode
3: rectifier 4: etching waste liquid
5: silver (Ag) precipitation 6: silver (Ag) precipitation apparatus
7: etching bath 8: nozzle
9: etching waste liquid transfer device 10: substrate
11: silver (Ag) conductive layer 12: photosensitive material layer
13: silver etching interface 14: etching film
100: etching apparatus

Claims (9)

A calcination tank filled with an etching waste solution containing silver;
A first deposition electrode and a second deposition electrode arranged opposite to each other; And
And a rectifier that connects the first deposition electrode and the second deposition electrode and applies a current. The method according to claim 1,
Wherein the first deposition electrode is a cathode and the second deposition electrode is an anode. The method according to claim 1,
Wherein the first deposition electrode and the second deposition electrode are made of a metal insoluble in the etching waste solution. The method according to claim 1,
Wherein the first deposition electrode is any one selected from the group consisting of Pt, Ir, Au, Al, Ag, and alloys thereof. The method according to claim 1,
Wherein the second deposition electrode is any one selected from the group consisting of Pt, Ir, Au, and alloys thereof. The method according to claim 1,
Wherein the etchant waste solution comprises 1 to 20 wt% of hydrogen peroxide, 0.1 to 4 wt% of a pH adjusting agent, 0.1 to 5 wt% of a chelating agent, 0.01 to 3 wt% of a cyclic amine compound, and 72 to 98.79 wt% Wherein the etchant is an etchant waste generated in a process of performing an etch reaction using an etchant containing an etchant. The method according to claim 1,
Wherein the etchant solution comprises 1 to 10% by weight of nitric acid, 50 to 75% by weight of phosphoric acid, 1 to 20% by weight of acetic acid, 0.5 to 3% by weight of an auxiliary oxide solubilizer, 0.001 to 0.01% , And water so that the total weight of the entire composition is 100 wt%. The apparatus for precipitating silver from an etching waste liquid according to claim 1, Etching the substrate including a single film of silver, a single film of silver alloy, and a multi-layer film composed of silver and a transparent conductive metal, using an etching solution;
Transferring the etching waste solution generated in the etching reaction to the silver (Ag) precipitation tank through the etching waste solution transfer device;
Connecting the first deposition electrode and the second deposition electrode to the silver deposition tank; And
And depositing silver (Ag) from the etching waste solution by applying a current to the first deposition electrode and the second deposition electrode. 9. The method of claim 8,
Wherein the current applied to the first deposition electrode and the second deposition electrode is in the range of 0.1 to 8.5 A and the voltage is in the range of 1 to 5 V.

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