KR20190023172A - Etchant composition for etching silver containing layer and method of forming conductive pattern using the same - Google Patents

Abstract

Embodiments of the present invention provide an etchant composition for etching a silver containing layer, which comprises an etching initiator, an inorganic acid, an organic acid, and extra water, wherein an absorption wavelength is 300-370 nm in 10,000 ppm of silver (Ag) concentration. The etchant composition for etching a silver containing layer is used to form a conductive pattern of a fine size, wherein an etching defect is reduced.

Description

TECHNICAL FIELD [0001] The present invention relates to a silver-containing film etchant composition and a method for forming a conductive pattern using the same. BACKGROUND ART [0002]

The present invention relates to a silver-containing film etchant composition and a method for forming a conductive pattern using the same. More particularly, the present invention relates to a metal film etchant composition containing an acid component and a method of forming a conductive pattern using the same.

For example, a thin film transistor (TFT) is used as a part of a driving circuit of a semiconductor device and a display device. The TFT is arranged for each pixel on a substrate of, for example, an organic light emitting display (OLED) device or a liquid crystal display device (LCD), and is connected to a pixel electrode, a counter electrode, a source electrode, a drain electrode, May be electrically connected to the TFT.

In order to form the electrode or the wiring, a metal film may be formed on a display substrate, a photoresist may be formed on the metal film, and then the metal film may be partially removed using an etchant composition.

The metal film may be formed of a multi-layered film containing dissimilar metals having different chemical properties, or a different kind of conductive material, in order to prevent the signal transmission delay by reducing the wiring resistance and ensure the chemical resistance and stability of the wiring.

For example, a transparent conductive oxide film such as indium tin oxide (ITO) may be additionally formed for forming a silver (Ag) -containing film and improving chemical resistance, stability, and transparency for realizing a low resistance property .

As described in Korean Patent Registration No. 10-0579421, inorganic acid strong acid such as phosphoric acid, sulfuric acid and the like is used as a base component of the etchant composition. However, when the inorganic strong acid is used, defects such as uneven etching profile, over-etch and over-hang depending on the difference in the etching rates of the different kinds of conductive films may be caused, It is difficult to control the etching rate for pattern formation.

In addition, silver (Ag) may be re-adsorbed, residues, etc. after the oxidation / reduction potential is low and may be etched. In this case, short-circuiting between adjacent conductive patterns may occur.

Korean Patent Registration No. 10-0579421 (2006.05.08.)

An object of the present invention is to provide a silver-containing film etchant composition having improved etch uniformity and high resolution.

One aspect of the present invention is to provide a method for forming a conductive pattern using the metal film etchant composition.

One aspect of the present invention is to provide a method of manufacturing a display substrate using the metal film etchant composition.

1. etch initiator; Inorganic acids; Organic acids; And an excess of water,

Wherein the absorption wavelength is 300 to 370 nm at a silver (Ag) concentration of 10,000 ppm.

2. The silver-containing film etchant composition of 1 above, wherein said etch initiator comprises at least one selected from the group consisting of peroxide peroxide, hydrogen peroxide, persulfate and perchlorate.

3. The silver-containing membrane etch composition of 2, wherein the etch initiator comprises oxone.

4. The silver-containing membrane etch composition of 1 above, wherein the inorganic acid comprises nitric acid.

5. The silver-containing film etchant composition of claim 1, wherein the organic acid comprises a first organic acid and a second organic acid that is weaker than the first organic acid.

6. The method of claim 5, wherein the first organic acid comprises acetic acid,

The second organic acid may be selected from the group consisting of iminodiacetic acid (IDA), glycine, salicylic acid, citric acid, formic acid, oxalic acid, malonic acid, Containing at least one member selected from the group consisting of succinic acid, butyric acid, gluconic acid, glycolic acid and pentanic acid. .

7. The silver-containing film etchant composition of 5 above, wherein the organic acid further comprises a polyvalent carboxylic acid.

8. The polyamic acid according to 7 above, wherein the polyvalent carboxylic acid is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), iminodiacetic acid (IDA), N- (2-Hydroxyethyl) ethylenediaminetriacetic acid (HEDTA), ethylene glycol-bis (β-aminoethyl ether) -N, N, N ', N'-tetraacetic acid N, N ', N'-tetraacetic acid (EGTA) and 1,2-bis (o-aminophenoxy) And at least one selected from the group consisting of 1,2-bis (o-aminophenoxy) ethane-N, N, N ', N'-tetraacetic acid: BAPTA.

9. The composition of claim 1, wherein,

0.5 to 9 wt% of the etch initiator;

1 to 10% by weight of the inorganic acid; And

10 to 65% by weight of the organic acid; And

And an excess of water.

10. The silver-containing film etchant composition of claim 1, which does not comprise phosphoric acid or phosphoric acid based compounds.

11. The silver-containing film etchant composition of 1 above, wherein the absorption wavelength is a wavelength corresponding to a maximum absorbance in the UV absorbance measurement.

12. A method comprising: forming a metal film on a substrate; And

And etching the metal film using the silver-containing film etchant composition according to any one of [1] to [11] above.

13. The method of claim 12, wherein said forming a metal film comprises forming a silver containing film.

14. The method of forming a conductive pattern according to claim 13, wherein the forming of the metal film further comprises forming a transparent conductive oxide film.

15. The conductive pattern forming method according to 14 above, wherein the transparent conductive oxide film includes a first transparent conductive oxide film and a second transparent conductive oxide film formed with the silver-containing film therebetween.

16. The transparent conductive oxide film according to claim 14, wherein the transparent conductive oxide film is made of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), gallium zinc oxide (GZO) and indium gallium zinc oxide Wherein at least one selected from the group comprises at least one selected from the group.

17. The method of claim 12,

Forming a thin film transistor on the substrate;

Forming a pixel electrode electrically connected to the thin film transistor; And

Forming a display layer on the pixel electrode,

Wherein the metal film is formed on the display layer.

18. The conductive pattern forming method according to 17 above, wherein the conductive pattern is provided as a common electrode, a reflective electrode, or a wiring of an image display apparatus.

19. The conductive pattern forming method of claim 12, wherein the conductive pattern is provided as a trace or sensing electrode of a touch sensor.

The silver-containing film etchant composition according to the embodiments of the present invention described above includes a etch initiator, inorganic acid, organic acid, and water, and may have a low absorption wavelength for silver. Thus, the solubility of silver in the composition is improved, and the re-adsorption of silver, precipitation can be prevented or suppressed.

According to exemplary embodiments, the inorganic acid comprises nitric acid, and the etching property control for fine pattern formation can be realized as the content of strong acid such as phosphoric acid, sulfuric acid, etc. is excluded or reduced. Further, the re-precipitation of silver and the residue phenomenon can be suppressed.

When the film to be etched includes the silver-containing film and the transparent conductive oxide film, the etchant initiates the metal oxide substitution reaction, and the silver-containing film and the transparent conductive oxide film can be uniformly etched together.

In some embodiments, the silver containing film etchant composition comprises a plurality of organic acids, whereby the uniformity of the etch profile can be significantly improved and the etching variations can be reduced.

Using the etchant composition, for example, an electrode or wiring such as a reflective electrode of a display device, a sensing electrode of a touch sensor, a trace, a pad, or the like can be formed to have a desired aspect ratio and profile.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a graph illustrating the absorption wavelength spectrum of an etchant composition in accordance with exemplary embodiments.
2 and 3 are cross-sectional views for explaining a conductive pattern forming method according to exemplary embodiments.
4 is a cross-sectional view illustrating a method of manufacturing a display substrate according to some exemplary embodiments.
5 is a schematic plan view illustrating a touch sensor formed in accordance with some exemplary embodiments.

According to embodiments of the present invention, a silver-containing film etchant composition (hereinafter abbreviated as "etchant composition") containing an etch initiator, inorganic acid, organic acid, and water and having an absorption wavelength of about 300 to 370 nm at a predetermined silver concentration Is provided. A conductive pattern forming method and a display substrate manufacturing method using the silver-containing film etchant composition described above are also provided.

The term " silver containing film "as used in the present application may refer to a film comprising silver or a silver alloy. Further, the silver-containing film may include a multilayer structure of two or more layers.

For example, the silver alloy may be at least one selected from the group consisting of neodymium (Nd), copper (Cu), palladium (Pd), niobium (Ni), nickel (Ni), molybdenum (Mo), chromium (Cr), magnesium (W), protactinium (Pa), titanium (Ti) or a combination of two or more thereof and an alloy of silver (Ag); A silver compound containing dopant elements such as nitrogen (N), silicon (Si), and carbon (C); Or a combination of two or more thereof.

The term " silver containing film "as used in this application is used to encompass a laminate of the silver containing film and one or more other conductive films. An example of the other conductive film is a transparent conductive oxide film containing a transparent metal oxide. For example, the transparent metal oxide may be selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), gallium zinc oxide (GZO), indium gallium zinc oxide (IGZO) .

Hereinafter, embodiments of the present invention will be described in detail and a case where a film to be etched includes a laminate of a silver-containing film and a transparent conductive oxide film will be described as an example. However, this is a preferable example, and the spirit and scope of the present invention are not necessarily limited thereto.

≪ Etchant composition &

The etch initiator included in the etchant composition according to embodiments of the present invention may be provided as a component capable of promoting the etching rate of silver (Ag) or the like and improving the etching uniformity. In addition, it may be included as a component for promoting etching by initiating or inducing a metal substitution reaction on a transparent conductive oxide film having a relatively low oxidation / reduction characteristic compared to silver.

In addition, since the etch initiator is included, the activity of the inorganic acid to be described later is promoted, so that the content of the inorganic acid can be relatively reduced. Therefore, it is possible to suppress the overeating angle, the etching unevenness, and the like which are caused when the inorganic acid is contained in excess.

According to exemplary embodiments, the etch initiator may comprise a sulfated peroxide, hydrogen peroxide, persulfate and / or nitrate, and may preferably comprise a sulfated peroxide such as oxone.

As the persulfate, at least one material selected from potassium persulfate (K ₂ S ₂ O ₈ ), sodium persulfate (Na ₂ S ₂ O ₈ ) or ammonium persulfate ((NH ₄ ) ₂ S ₂ O ₈ ) , At least one material selected from the group consisting of potassium nitrate (KNO ₄ ), sodium nitrate (NaNO ₄ ) and ammonium nitrate (NH ₄ NO ₄ ) may be used as the nitrate.

In some embodiments, the etch initiator may be included in an amount of about 0.5 to 9 weight percent of the total composition weight. If the content of the etch initiator is less than about 0.5 wt%, the etch rate for the silver-containing film may be excessively lowered and non-uniform etching may be caused. In addition, wiring shorts may occur due to silver residue, and the effect of promoting etching of the transparent conductive oxide film may be insignificant. If the content of the etch initiator is more than about 9 wt%, the oxidizing action of the inorganic acid may be deteriorated, and the etching rate of the transparent conductive oxide film may be excessively lowered.

The inorganic acid may act as an oxidant by interacting with the etch initiator described above. For example, the inorganic acid may serve as a main oxidant for a transparent conductive oxide film such as ITO. The inorganic acid and the etch initiator work together, so that the silver-containing film and the transparent conductive oxide film can be uniformly etched together.

According to exemplary embodiments, the inorganic acid may comprise nitric acid. In some embodiments, the inorganic acid may comprise nitrate. Examples of the nitrate include sodium nitrate, potassium nitrate, ammonium nitrate, and the like. These may be used alone or in combination of two or more.

In some embodiments, the inorganic acid may be included in an amount of about 1 to 10% by weight of the total weight of the composition. If the content of the inorganic acid is less than about 1% by weight, the etching rate may be too low to cause a wiring short due to, for example, ITO residues and silver residues. In addition, dark spots or blind spots may occur due to the ITO residues or silver residues. If the content of the inorganic acid exceeds about 10% by weight, etching control failure of the metal film such as an overexposure angle may occur.

In one embodiment, the content of the inorganic acid may be adjusted to about 1 to 9% by weight considering the uniform etching rate and the control characteristics of the silver-containing film and the transparent conductive oxide film.

The organic acid may be included, for example, to reduce the critical dimension loss (CD loss) of the conductive pattern obtained by appropriately promoting or controlling the etching rate of the silver-containing film and to promote fine pattern formation.

In some embodiments, the organic acid may comprise a first organic acid and a second organic acid that is less acidic than the first organic acid.

For example, the first organic acid comprises acetic acid and can function as a co-oxidant or as a peroxide for the silver. The second organic acid may be selected from the group consisting of iminodiacetic acid (IDA), glycine, salicylic acid, citric acid, formic acid, oxalic acid, malonic acid, Succinic acid, butyric acid, gluconic acid, glycolic acid, pentanic acid, and the like. These may be used alone or in combination of two or more. Preferably, oxalic acid may be used as the second organic acid.

The second organic acid may function as an etch profile promoter. The oxidative action by the first organic acid is partially suppressed or controlled by the second organic acid, so that the CD loss or the CD bias of the conductive pattern can be remarkably reduced.

In some exemplary embodiments, the organic acid may further include a polycarboxylic acid in addition to the first and second organic acids. For example, the polyvalent carboxylic acid may be included as a component that finely adjusts the sidewall profile of the conductive pattern by the ion trapping effect by the chelating action.

Examples of the polycarboxylic acid include, but are not limited to, ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), iminodiacetic acid (IDA), N- (2 (2-Hydroxyethyl) ethylenediaminetriacetic acid (HEDTA), ethylene glycol-bis (β-aminoethyl ether) -N, N, N ', N'-tetraacetic acid N, N ', N'-tetraacetic acid (EGTA), 1,2-bis (o-aminophenoxy) (1,2-bis (o-aminophenoxy) ethane-N, N, N ', N'-tetraacetic acid: BAPTA). These may be used alone or in combination of two or more.

In some embodiments, the organic acid may be included in an amount of about 10-65 wt% of the total weight of the composition. If the content of the organic acid is less than about 10% by weight, stains and residues may occur due to a decrease in the etching rate. If the content of the organic acid exceeds about 65% by weight, the stability of the composition with time may deteriorate, and the pattern may be lost due to the overeating angle.

Considering the improvement of the profile characteristics of the conductive pattern, in one preferred embodiment, the content of the organic acid may be about 20 to 40% by weight.

The etchant composition may include excess or residual water except for the above-mentioned components, for example, deionized water. In the case of the deionized water, for example, it may have a resistivity value of 18 M? / Cm or more.

The term "extra or remaining amount " as used in the present application means a variable amount including the amounts of the above-mentioned components and the above additives, when other additives are included.

In some embodiments, the additive may be included to improve etch efficiency or etch uniformity to the extent that it does not interfere with the action of the components described above. For example, the additive may include anti-corrosion, anti-adhesion of etching by-products, formulation for adjusting the taper angle of the etching pattern, and the like widely used in the art.

In some embodiments, the etchant composition may be substantially composed of the etch initiators, inorganic acids, organic acids, and water described above.

In some embodiments, the etchant composition may not comprise phosphoric acid or phosphoric acid based compounds (e.g., phosphates). In the case of the phosphoric acid or phosphoric acid-based compound, loss due to overgrowth of the metal film, damage to the lower structure, and re-adsorption may occur. In addition, in the case of the phosphoric acid or phosphoric acid compound, the viscosity of the etching solution composition may be excessively increased to cause an etching deviation in each region of the etching target film.

However, as the phosphoric acid or the phosphoric acid-based compound is excluded from the etchant composition, it is possible to form a conductive pattern having a fine pattern size while preventing over-etching of the silver-containing film.

The inorganic acid included in the etchant composition according to some exemplary embodiments is substantially composed of nitric acid, and may not include hydrochloric acid and sulfuric acid. Thus, an environmental pollution problem and an etching process with reduced silver precipitation problems can be realized.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a graph illustrating the absorption wavelength spectrum of an etchant composition in accordance with exemplary embodiments.

The etchant composition according to exemplary embodiments may have an absorption wavelength of about 300 to 370 nm upon dissolving 10,000 ppm of silver (Ag) concentration. As shown in FIG. 1, the absorption wavelength may mean a wavelength indicating the maximum absorbance at the time of UV-absorbance measurement at the silver concentration. In some embodiments, the absorption wavelength may have a value of about 360 nm or less.

With the absorption wavelength range, the silver solution composition of the etchant composition can improve the silver solubility of the composition, prevent silver particles, precipitation, re-adsorption, and agglomeration, and can substantially uniformly and finely etch the silver-containing film. In addition, sidewall loss, tip phenomenon, and the like can be suppressed while obtaining a desired taper angle of the conductive pattern by interaction of the components within the absorption wavelength range.

<Conductive Pattern Forming Method>

2 and 3 are cross-sectional views for explaining a conductive pattern forming method according to exemplary embodiments.

Referring to FIG. 2, a lower conductive pattern 115 and a lower insulating layer 110 may be formed on a substrate 100.

The substrate 100 may include a glass substrate, a polymer resin or a plastic substrate, an inorganic insulating substrate, or the like.

The lower conductive pattern 115 includes a transparent conductive oxide such as aluminum (Al), copper (Cu), molybdenum (Mo), tungsten (W), titanium (Ti), tantalum . The lower insulating film 110 may be formed to include an organic insulating material such as acrylic resin, polysiloxane, and the like, and / or an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, and the like.

The lower conductive pattern 115 may be provided, for example, as a conductive via or a conductive contact.

According to exemplary embodiments, the first transparent conductive oxide film 121, the silver-containing film 123, and the second transparent conductive oxide film 125, which are sequentially stacked on the lower insulating film 110 and the lower conductive pattern 115, The metal film 120 can be formed.

The first and second transparent conductive oxide films 121 and 125 may be formed to include a transparent metal oxide such as ITO, IZO, GZO, IGZO, or the like. The silver containing film 123 may be formed to include a silver and / or silver alloy as described above. The first transparent conductive oxide film 121, the silver containing film 123 and the second transparent conductive oxide film 125 may be formed through a deposition process such as a sputtering process.

A mask pattern 130 may be formed on the metal film 120. For example, after the photoresist film is formed on the second transparent conductive oxide film 125, the photoresist film may be partially removed through the exposure and development processes to form the mask pattern 130.

Referring to FIG. 3, the metal film 120 may be etched using the silver-containing film etchant composition according to the above-described exemplary embodiments to form the conductive pattern 120a. The conductive pattern 120a includes a first transparent conductive oxide film pattern 122, a silver-containing pattern 124 and a first transparent conductive oxide film pattern 126 which are sequentially stacked on the lower insulating film 110 .

The conductive pattern 120a can be utilized, for example, as a pad, an electrode, or a wiring of an image display apparatus. By forming the relatively silver-containing pattern 124 having a low resistance and a good signal transmission property between the first and second transparent conductive oxide film patterns 122 and 126 having excellent corrosion resistance, a low resistance and mechanical and chemical reliability An improved conductive pattern can be realized.

In addition, by utilizing the etchant composition including the etching initiator, inorganic acid, and organic acid described above and having a predetermined absorption wavelength range for silver and improved solubility, the intricate and overeating angles of the silver containing pattern 124 are prevented, A conductive pattern 120a having a substantially uniform and continuous sidewall profile can be formed.

In some embodiments, the thickness of the silver containing film 123 or the silver containing pattern 124 may be at least about 800 A, and in one embodiment at least about 1000 A. The thickness of the first and second transparent conductive oxide film patterns 122 and 126 may be about 50 to 100 ANGSTROM.

As the thickness of the silver-containing pattern 124 increases to realize low resistance and the aspect ratio of the conductive pattern 120a increases, etching defects may be caused by the silver residue and overeating angle. However, a wet etching process in which the etch failure is suppressed using the etchant composition according to the exemplary embodiments can be realized.

4 is a cross-sectional view illustrating a method of manufacturing a display substrate according to exemplary embodiments. For example, Fig. 4 shows a display substrate including a wiring and an electrode structure formed by the conductive pattern forming method described above.

Referring to FIG. 4, a thin film transistor (TFT) may be formed on a substrate 200. For example, the TFT may include an active layer 210, a gate insulating film 220, and a gate electrode 225.

According to exemplary embodiments, after the active layer 210 is formed on the substrate 200, the gate insulating film 220 covering the active layer 210 may be formed.

The active layer 210 may be formed to include an oxide semiconductor such as polysilicon or, for example, indium gallium zinc oxide (IGZO). The gate insulating film 220 may be formed to include silicon oxide, silicon nitride, and / or silicon oxynitride.

A gate electrode 225 may be formed on the gate insulating layer 220 to overlap with the active layer 210. The gate electrode 225 may be formed to include a metal such as Al, Ti, Cu, W, Ta, Ag, or the like.

The interlayer insulating film 230 covering the gate electrode 225 is formed on the gate insulating film 220 and then the source electrode 233 which is in contact with the active layer 210 through the interlayer insulating film 230 and the gate insulating film 220 And the drain electrode 237 can be formed. The source electrode 233 and the drain electrode 237 may be formed to include a metal such as Al, Ti, Cu, W, Ta, or Ag.

A via insulating film 240 covering the source electrode 233 and the drain electrode 237 may be formed on the interlayer insulating film 230. The via insulating film 240 may be formed using an organic insulating material such as an acrylic type, a siloxane type resin, or the like.

A pixel electrode 245 electrically connected to the drain electrode 237 may be formed on the via insulating layer 240. The pixel electrode 245 may include a via portion that contacts the drain electrode 237 through the via insulating layer 240. The pixel electrode 245 may be formed to include a metal such as Al, Ti, Cu, W, Ta, Ag, and / or a transparent conductive oxide.

The pixel defining layer 250 may be formed on the via insulating layer 240 and the display layer 255 may be formed on the pixel defining layer 250 exposed by the pixel defining layer 250. The display layer 255 may be formed of, for example, a liquid crystal layer included in an organic light emitting layer (EML) or an LCD device included in an OLED device.

The counter electrode 260 may be formed on the pixel defining layer 250 and the display layer 255. The counter electrode 260 may be provided as a common electrode, a reflective electrode, or a cathode of an image display apparatus.

According to exemplary embodiments, the counter electrode 260 may be formed by sequentially laminating a first transparent conductive oxide film, a silver-containing film, and a second transparent conductive oxide film, and then patterning through a wet etching process using the above- .

Thus, the counter electrode 260 includes the first transparent conductive oxide film pattern 262, the silver-containing pattern 124 and the second transparent conductive oxide film pattern 262 sequentially stacked on the pixel defining layer 250 and the display layer 255. [ (266).

In some embodiments, the image display device may include a display area I and a non-display area II. The TFT, the pixel electrode 245, the display layer 255, and the counter electrode 260 described above can be formed on the display region I. A wiring 270 may be formed on the non-display area II. The wiring 270 may be electrically connected to the TFT or the counter electrode 260.

The wiring 270 also includes a first transparent conductive oxide film pattern 272, a silver-containing pattern 274 and a second transparent conductive oxide film pattern 276 which are sequentially stacked, for example, on the via insulating film 240, May be patterned using the etchant composition in accordance with the illustrative embodiments.

In one embodiment, the lines 270 may be formed together by a wet etch process that is substantially the same as the counter electrodes 260 on the display area I.

As described above, by forming the counter electrode 260 and / or the wiring 270 of the image display apparatus in a laminated structure including the first transparent conductive oxide film pattern-containing pattern-second transparent conductive oxide film pattern, While implementing resistance properties, mechanical / chemical stability and optical properties can be improved together. Further, when the above-mentioned etchant composition is used, defects such as silver residue, silver ash adsorption, side damage, tip development, and the like can be suppressed.

In some embodiments, patterning of the gate electrode 225, the source electrode 233, the drain electrode 237, and the pixel electrode 245 may be performed utilizing the etching solution composition or the conductive pattern forming method described above.

5 is a schematic plan view illustrating a touch sensor formed in accordance with some exemplary embodiments.

5, the touch sensor may include a sensing electrode 310, a trace 320, and a pad 330 formed on a substrate 300.

The touch sensor may include a sensing area (A) and a peripheral area (B). The trace 320 and the pad 330 may be formed on the substrate 300 of the sensing area A of the sensing electrode 310 and the trace 320 and the pad 330 may be formed on the substrate 300 of the peripheral area B.

The sensing electrode 310 may include a first sensing electrode 310a and a second sensing electrode 310b arranged in a first direction and a second direction which are parallel to the upper surface of the substrate 300 and intersect perpendicularly to each other, . &Lt; / RTI &gt;

The first sensing electrode 310a extends in the first direction and a plurality of first sensing electrodes 310a may be formed along the second direction. The second sensing electrode 310b may extend in the second direction and may include a plurality of second sensing electrodes 310b along the first direction.

Each of the first and second sensing electrodes 310a and 310b may include a polygonal unit pattern, for example, and may include a connection unit for connecting neighboring unit patterns. The inside of the unit pattern may include a conductive pattern patterned in a mesh type.

A trace 320 may be branched from each of the sensing electrodes 310a and 310b and a distal end of the trace 320 may be connected to the pad 330. [ The touch sensor 300 may be connected to an external circuit such as a flexible printed circuit board (FPCB) through a pad 330.

According to exemplary embodiments, the traces 320 may be formed through a wet etch process using the etchant composition described above. In some embodiments, the trace 320 may be formed in a stacked structure of a first transparent conductive oxide film pattern-containing pattern-second transparent conductive oxide film pattern.

In one embodiment, sensing electrode 310 and / or pad 330 may also be formed through a wet etch process using the etchant composition. For example, the sensing electrode 310 and / or the pad 330 may be formed together through a wet etch process that is substantially the same as the trace 320. In this case, the sensing electrode 310 and / or the pad 330 may also be formed as a laminated structure of the first transparent conductive oxide film pattern-containing pattern-second transparent conductive oxide film pattern.

As the conductive patterns of the touch sensor include the above-described laminated structure of the silver-containing pattern and the transparent conductive oxide film pattern, the mechanical stability such as the electrical property such as the sensing sensitivity and the crack resistance can be improved together.

As described above, various conductive patterns having improved electrical, mechanical, and chemical properties can be formed by using the metal film etchant composition according to the exemplary embodiments, which are included in an image display device, a touch sensor, and the like.

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. It will be apparent to those skilled in the art that various changes and modifications can be made to the embodiments within the spirit and scope of the appended claims.

Examples and Comparative Examples

The etchant compositions according to Examples and Comparative Examples were prepared with the components and the contents (% by weight) shown in Table 1 below. For each etchant composition, the absorption wavelength was measured using a UV-Vis spectrophotometer of S-3100 Model manufactured by SCINCO Co., in which 10,000 ppm of silver (Ag) was dissolved.

nitric acid Etch initiator
(Oxone) Phosphoric acid Organic acid water absorption
wavelength
(nm) Acetic acid Oxalic acid DTPA Example 1 9 0.5 - 20 3 0.5 Balance 320 to 330 Example 2 5 5 - 20 One One Balance 320 to 330 Example 3 One 9 - 20 0.5 3 Balance 335 to 345 Example 4 9 0.5 - 30 3 One Balance 340 to 350 Example 5 5 5 - 30 One 3 Balance 325 to 335 Example 6 One 9 - 30 0.5 5 Balance 328 to 338 Example 7 9 5 - 10 3 One Balance 345 to 355 Example 8 5 5 - 30 - 3 Balance 350 ~ 355 Example 9 5 5 - 40 3 - Balance 350 ~ 355 Example 10 5 3 - 50 3 5 Balance 350 ~ 355 Example 11 5 3 - 60 3 5 Balance 350 ~ 355 Comparative Example 1 - 5 - 10 3 0.5 Balance 500 ~ 510 Comparative Example 2 5 5 - 40 - One Balance 380 to 390 Comparative Example 3 5 - - 30 One 3 Balance 380 to 390 Comparative Example 4 5 5 - One One Balance 450 to 460 Comparative Example 5 3 5 - 20 3 - Balance 380 to 390 Comparative Example 6 3 0.5 5 10 3 0.2 Balance 400 to 410

Experimental Example

A triple film of ITO (100 Å) / Ag (1000 Å) / ITO (100 Å) was formed on a glass substrate, and a sample cut into a size of 10 cm × 10 cm was prepared using a diamond knife.

The triplet film was etched through a photolithography process. Specifically, the etchant compositions of Examples and Comparative Examples were injected into a spray type etching equipment (ETCHER, K.C.Tech). The temperature of the etchant composition was set at 40 ° C., and when the temperature reached 40 ± 0.1 ° C., the etchant composition was sprayed onto the sample and the etch process was performed for 85 seconds.

After the etching process was completed, the sample was rinsed with deionized water, dried using a hot air drying apparatus, and the photoresist was removed using a photoresist stripper (PR stripper).

(1) is a re-adsorption evaluation

The etched samples were evaluated on the basis of an electron scanning microscope (SU-8010, manufactured by HITACHI Co., Ltd.) to determine the resorption of silver. The evaluation criteria are as follows.

◎: silver absorber site not observed

○: Observation of less than 20 silver adsorption sites

X: more than 20 silver adsorption sites

(2) Evaluation of etch rate (ER)

The thickness of the etched sample was measured using a scanning electron microscope (SU-8010, manufactured by Hitachi), and the thickness of the etched sample was divided by the etch time to measure the longitudinal etch rate. Thereafter, the etching rate was evaluated according to the following criteria, and the results are shown in Table 2 below.

<Evaluation Criteria>

◎: longitudinal etching rate is over 30 Å / sec

?: Longitudinal etching rate of 20 to 30 A / sec

X: longitudinal etching rate is less than 20 Å / sec

(3)

After the etching process was completed, the etched samples were rinsed with deionized water, dried using a hot-air drier, and remainder of the etched metal, precipitation or the like was measured using an electron microscope (SU-8010, manufactured by Hitachi) Were observed.

(4) Pattern straightness evaluation

The sidewall of the etched sample was observed by an electron scanning microscope (SU-8010, manufactured by HITACHI Co., Ltd.), and the straightness of the pattern was evaluated. The evaluation criteria are as follows.

⊚: substantially the pattern side wall is formed as a continuous straight line

○: Unevenness of some sidewalls (irregularities, recesses, bent portions)

X: Formation of a substantially constant etched surface

The evaluation results of the above-described experimental examples are shown together in Table 2 below.

division Re-adsorption Etching rate Precipitation of silver Straightness Example 1 ◎ ◎ none ◎ Example 2 ◎ ◎ none ◎ Example 3 ◎ ◎ none ◎ Example 4 ◎ ◎ none ◎ Example 5 ◎ ◎ none ◎ Example 6 ◎ ◎ none ◎ Example 7 ◎ ◎ none ◎ Example 8 ○ ○ none ◎ Example 9 ○ ○ none ○ Example 10 ○ ○ none ◎ Example 11 ○ ○ none ◎ Comparative Example 1 X X Occur X Comparative Example 2 X ◎ Occur ○ Comparative Example 3 ○ ○ Occur ○ Comparative Example 4 X X Occur X Comparative Example 5 X ◎ Occur X Comparative Example 6 X X Occur X

Referring to Table 2, the etchant compositions according to the examples which included the etching initiator, the inorganic acid, and the organic acid, and which were controlled within the wavelength range of 300 to 370 nm exhibited an improved etching rate without causing silver sorption / precipitation . In addition, in Examples 1 to 7 including oxalic acid and DPPA in combination, the silver re-adsorption was substantially blocked, and an excellent etching rate and pattern profile were exhibited.

On the other hand, all of the comparative examples in which the absorption wavelength exceeded 370 nm resulted in precipitation and some silver reabsorption. Therefore, the pattern straightness was remarkably deteriorated. In the case of Comparative Example 6 containing phosphoric acid, the etch rate of the ITO film was lowered, resulting in poor etching rate, and both silver adsorption and precipitation were caused.

100, 200: substrate 110: lower insulating film
115: lower conductive pattern 120: metal film
120a: conductive pattern 121: first transparent conductive oxide film
122, 262, and 272: a first transparent conductive oxide film pattern
123: Silver-containing film 124, 264, 274: silver-containing pattern
125: second transparent conductive oxide film
126, 266, 276: a second transparent conductive oxide film pattern
210: active layer 210: gate electrode
233: source electrode 237: drain electrode
245: pixel electrode 260: opposing electrode
270: wiring 300: substrate
310: sensing electrode 320: trace
330: Pad

Claims (19)

Etch initiators; Inorganic acids; Organic acids; And an excess of water,
Wherein the absorption wavelength is 300 to 370 nm at a silver (Ag) concentration of 10,000 ppm.
The silver-containing membrane etch composition of claim 1, wherein the etch initiator comprises at least one selected from the group consisting of peroxide peroxide, hydrogen peroxide, persulfate, and perchlorate.
3. The silver-containing membrane etch composition of claim 2, wherein the etch initiator comprises oxone.
2. The silver-containing film etch composition of claim 1, wherein the inorganic acid comprises nitric acid.
2. The silver-containing film etch composition of claim 1, wherein the organic acid comprises a first organic acid and a second organic acid that is less acid than the first organic acid.
The method of claim 5, wherein the first organic acid comprises acetic acid,
The second organic acid may be selected from the group consisting of iminodiacetic acid (IDA), glycine, salicylic acid, citric acid, formic acid, oxalic acid, malonic acid, Containing at least one member selected from the group consisting of succinic acid, butyric acid, gluconic acid, glycolic acid and pentanic acid. .
6. The silver-containing film etch composition of claim 5, wherein the organic acid further comprises a polycarboxylic acid.
8. The method of claim 7, wherein the polyvalent carboxylic acid is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), iminodiacetic acid (IDA), N- (2-Hydroxyethyl) ethylenediaminetriacetic acid (HEDTA), ethylene glycol-bis (? -Aminoethyl ether) -N, N, N ', N'-Ntetraacetic acid N, N ', N'-tetraacetic acid (EGTA) and 1,2-bis (o-aminophenoxy) And at least one selected from the group consisting of 1,2-bis (o-aminophenoxy) ethane-N, N, N ', N'-tetraacetic acid: BAPTA.
The composition according to claim 1,
0.5 to 9 wt% of the etch initiator;
1 to 10% by weight of the inorganic acid; And
10 to 65% by weight of the organic acid; And
And an excess of water.
The silver-containing film etch composition according to claim 1, which does not contain phosphoric acid or phosphoric acid-based compounds.
The silver-containing film etch composition of claim 1, wherein the absorption wavelength is a wavelength corresponding to a maximum absorbance at the time of UV absorption measurement.
Forming a metal film on the substrate; And
And etching the metal film using the silver-containing film etchant composition of any one of claims 1-11.
13. The method of claim 12, wherein forming the metal film comprises forming a silver containing film.
14. The method of claim 13, wherein forming the metal film further comprises forming a transparent conductive oxide film.
15. The conductive pattern forming method according to claim 14, wherein the transparent conductive oxide film includes a first transparent conductive oxide film and a second transparent conductive oxide film formed with the silver-containing film therebetween.
15. The method according to claim 14, wherein the transparent conductive oxide film is formed from a group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), gallium zinc oxide (GZO) and indium gallium zinc oxide (IGZO) And at least one selected.
The method of claim 12,
Forming a thin film transistor on the substrate;
Forming a pixel electrode electrically connected to the thin film transistor; And
Forming a display layer on the pixel electrode,
Wherein the metal film is formed on the display layer.
The conductive pattern forming method according to claim 17, wherein the conductive pattern is provided as a common electrode, a reflective electrode, or a wiring of an image display apparatus.
13. The method of claim 12, wherein the conductive pattern is provided as a trace or sensing electrode of a touch sensor.

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