KR101256276B1 - Etchant composition for etching a conductive multi-layer film and etching method using the same - Google Patents

Abstract

The present invention relates to the combination of molybdenum or molybdenum alloy with one or more layers of copper or copper alloy, such as Cu / Mo laminated metal film, Cu / Mo-alloy laminated metal film, Cu-alloy / Mo-alloy laminated metal film Provided is an etchant capable of efficiently and excellently batch-etching multiple films comprising at least one layer simultaneously. The present invention is based on the total weight, 50-80 wt% phosphoric acid; Nitric acid 0.5-10 wt%; Acetic acid 5-30 wt%; 0.01-5 wt% of imidazole; And it relates to an etchant comprising a residual amount of water, and also relates to an etching method of a multilayer using such an etchant. The additive imidazole here serves as a Cu / Mo galvanic reaction controller.

Description

Etching liquid composition of the multilayer and the etching method thereof {ETCHANT COMPOSITION FOR ETCHING A CONDUCTIVE MULTI-LAYER FILM AND ETCHING METHOD USING THE SAME}

The present invention relates, in particular, to an etchant for the patterning of conductive layers used in thin film transistors (TFTs) or touch sensor panels of flat panel displays. In particular, the present invention provides an etching solution for etching a multilayer comprising at least one layer of copper (Cu) or copper alloy (Cu-alloy) and at least one layer of molybdenum (Mo) or molybdenum alloy (Mo-alloy). In particular, the present invention relates to an etchant for collectively etching Cu / Mo bilayers. In addition, the present invention relates to an etching method of a multilayer using such an etchant.

Conventionally, Cu is not used as a single layer as a low-resistance metal electrode, and a molybdenum (Mo) or titanium (Ti) film is formed as a diffusion barrier at the bottom of the copper, and copper (Cu), which is pure copper, is formed thereon. A TFT gate electrode and a source / drain electrode were formed from a double film of / Mo or Cu / Ti. The etching solution of the double membrane as described above is impossible to form a desired pattern according to the TFT conditions when using a conventional phosphoric acid mixed acid, and contains a small amount of fluorine ions as a hydrogen peroxide-based (unstable, large amount of waste solution, and a large amount of pure water used). When the mixed acid is used as an etchant, when the amount is excessive, there is a problem of etching the glass used as the substrate. In addition, when using a composition of phosphoric acid + nitric acid + acetic acid + water, which is a conventional mixed acid-based aluminum etchant, the etching rate is too fast, thus making it difficult to form a desired TFT pattern (hence, a control agent for controlling (lowering) the Cu etching rate). That is, a Cu etching rate regulator is required.

In addition, WO 2009/038063 discloses an etching solution containing hydrogen peroxide capable of collectively etching a Cu / Mo laminated metal film (or a Cu alloy / Mo alloy laminated metal film). There is a disadvantage that occurs, especially there is a problem of stability of the etchant.

In recent years, the permeate mixture has been attracting attention as an etchant in the technical field to which the present invention belongs, but in general, when the metal is included in the hydrogen peroxide, there is a problem in that the decomposition reaction of the hydrogen peroxide by the metal causes an unstable state. In more detail, the rapid decomposition of hydrogen peroxide may cause concentration change with the progress of the etching process, that is, the rapid increase in the temperature of the etchant, the risk of explosion, and the increase in the manufacturing cost according to the needs of the auxiliary equipment. Therefore, there are many problems in using the fruit juice mixture as an etchant.

As such, the existing fruit-based etchant had problems of explosiveness (stability of chemicals such as waste water treatment problems) and short lifespan.In particular, in case of Cu / Mo double layer, fluorine-containing compounds (fluorine compounds) are essential to remove the residue due to the residue of Mo. Must be added to the etchant, which leads to the disadvantage of damaging the glass substrate.

Therefore, in order to solve the above problems, a new etchant composition of non-hydrogen peroxide (H ₂ O ₂ ) / non-fluorine compound based which can simultaneously etch Cu / Mo multilayers is used. Development is required.

Copper etchant containing phosphoric acid nitric acid and other additives The existing patents have been proposed in the published patent publication KR 10-2009-0095408 A and published patent publication KR 10-2006-0082270 A, but the specific application of the etching solution to the Cu / Mo multilayer structure The results are unknown.

Therefore, only one wet etching process is performed on Cu / Mo multilayers without including environmentally harmful substances such as hydrogen peroxide (a large amount of waste liquid), unstable components that shorten the life of the etchant, or fluorine-based compounds that corrode the glass of the substrate. There is a need for the development of new etchant compositions that can achieve good etch profiles.

The galvanic reaction is a phenomenon that occurs when different metals are contacted in solution or in the atmosphere. It refers to a phenomenon in which the etching rate is significantly changed due to the electrochemical electromotive force difference in the electrolyte between dissimilar metals. The rate of oxidation and reduction of the two metals is determined by the relative potential difference in the solution of the two metals. In general, the higher the electrochemical potential of the two metals in the solution (noble) acts as a cathode (cathode), the reduction reaction is predominant, and the etching rate is slow compared to the single film. Active metals with lower potentials act as anodes, further accelerating the oxidation reaction, and are faster than when the etching rate is a single film.

In this study, it was confirmed that the potential of copper and molybdenum in the phosphate-based etchant was greatly changed depending on the addition of nitric acid, and before the addition of nitric acid, copper had a higher potential than molybdenum. Acted as. However, after the addition of an oxidizing agent such as nitric acid, copper has a lower potential than molybdenum, thereby acting as an anode, resulting in overetching. That is, since copper and molybdenum have different etching speeds in the same etchant, copper may be overetched before molybdenum is etched, resulting in a loss of straightness or an increase in resistance of the entire wiring.

In order to compensate for this problem, when two or more etching solutions having different compositions for copper and lower interconnections (Mo and Ti) are used, the entire etching process is complicated, and the manufacturing cost and time are increased, thereby reducing product productivity. There is this. To simplify process and reduce manufacturing costs, an etchant is needed to etch multiple films at once, such as Cu / Mo double wiring.

In addition, the current thin film transistor wiring process is simplifying the patterning process of metal wiring to reduce the process cost, and as applied to a large area substrate, a new etchant composition exhibiting uniform etching characteristics regardless of the material forming the multilayer film when etching. Development is required.

Additionally, as suggested in patent documents US 2009/0160824 A1 or US 2009/0096759 A1, metal conductive multilayers can also be projected capacitive (projected) or resistive (resistive) touch sensor structures. or for resistive touch sensor structures). The touch sensor structure may be formed, for example, in an additional substrate disposed inside or outside the color filter substrate of the TFT-LCD, or in front of the display.

For small touch sensors, single layer molybdenum (Mo), MoTa, or MoTa films are used for metallization, and transparent conductive films (eg Indium tin oxide (ITO)) are used. In addition, multiple films such as Al / Mo, AlNd / Mo, and AlNd / Mo-Alloy are also used for the conductive film, but the need for low resistance metallization for large touch screens arises. As a result, multiple films of Cu / Mo or Cu / Mo-alloy should be used.

The patterning of the metal wiring is preferably achieved by wet etching, and the problems of patterning these metal multilayers for touch sensors are the same as for thin film transistors.

In order to solve the above problems of the prior art, the present invention includes a Cu / Mo laminated metal film, a Cu / Mo-alloy laminated metal film, and a Cu-alloy / Mo-alloy laminated metal film, one or more of copper or copper alloy. Simultaneous batch etching of layers and multiple films comprising at least one layer of molybdenum or molybdenum alloy simplifies the manufacturing process, thereby reducing manufacturing costs and time, as well as having excellent profile and etching properties It is an object of the present invention to provide an etching liquid composition having excellent stability of a chemical solution in a process and an etching method of a multilayer using the same.

In order to achieve the above object, the etching solution of the present invention preferably comprises imidazole to improve the etching profile (step length / CD (critical dimension) skew reduction) as an additive to the non-fruited / non-fluorine phosphoric acid-based etching solution. do. In the present invention, the phosphoric acid-based etchant is more stable than the fruit tree-based, and according to the research of the present inventors, unlike the fruit-based etchant, unlike the fruit-based etchant, the problem of Mo residue rarely occurs. The fluorine compound, which is a component included in most of the etching solution, is also unnecessary, and the composition of the present invention has a very simple composition of simply adding imidazole to a conventional stable phosphoric acid-based etching solution (phosphate + nitric acid + acetic acid + water).

The present invention provides an etchant comprising phosphoric acid (H ₃ PO ₄ ), nitric acid (HNO ₃ ), acetic acid (CH ₃ COOH), imidazole (C ₃ H ₄ N ₂ ) and water (H ₂ O). do.

In order to achieve the above object, the present invention is preferably 50 to 80 wt% of phosphoric acid (H ₃ PO ₄ ); Nitric acid (HNO ₃ ) 0.5-10 wt%; Acetic acid (CH ₃ COOH) 5-30 wt%; 0.01-5 wt% of imidazole (C ₃ H ₄ N ₂ ) as an additive; And it provides an etchant composition comprising a residual amount of water.

More preferably, the present invention is 50 to 75 wt% of phosphoric acid based on the total weight of the composition; Nitric acid 1-9 wt%; Acetic acid 14-20 wt%; 0.1 to 0.3 wt% of imidazole (C ₃ H ₄ N ₂ ) as an additive; And it provides an etchant composition comprising a residual amount of water.

The etchant composition of the present invention is for wet etching a multilayer comprising at least one layer of copper or copper alloy and at least one layer of molybdenum or molybdenum alloy. Preferably, these multilayers can also be used for batch etching simultaneously. The multilayer includes, for example, a Cu / Mo laminated metal film, a Cu / Mo-alloy laminated metal film, a Cu-alloy / Mo-alloy laminated metal film, and the like. Among them, in particular, it can be used as an etchant for batch etching Cu / Mo bilayers.

In particular, the present invention is an etching solution for Cu / Mo double membranes, which is based on phosphoric acid series (phosphate, nitric acid, acetic acid), and further includes imidazole as an additive to reduce the galvanic effect (ie, imidazole). Silver copper / molybdenum galvanic reaction controller.

In addition, the etchant composition of the present invention is preferably a non-perfluoro / non-fluorine compound solution, and does not include hydrogen peroxide and / or a fluorine compound (fluorine compound) as a component.

The present invention can simultaneously and efficiently etch multiple films, in particular Cu (or Cu-alloy) / Mo (or Mo-alloy) multilayers, based on stable phosphoric acid as compared to fruit trees.

Water acts as a copper oxidant and is preferably included in the etchant in residual amounts. In general, when the etchant contains an excessive amount of water, the step length is increased by increasing the etching rate of copper and promoting the galvanic phenomenon of copper and molybdenum.

Phosphoric acid (H ₃ PO ₄ ) serves as a basic oxidizing agent, it is preferably included in 50 to 80% by weight relative to the total weight of the composition. When the phosphoric acid is less than 50% by weight, the over-etching phenomenon occurs as the water content increases, and even when it exceeds 80% by weight, the over-etching and non-uniform etching characteristics can be observed. The higher the ratio of pure phosphoric acid, the better.

Nitric acid (HNO ₃ ) serves as a copper oxidizing agent, it is preferably included in 0.5 to 10% by weight based on the total weight of the composition. When less than 0.5% by weight of nitric acid is included, the etching rate of copper is too low, if more than 10% by weight is included galvanic phenomenon of copper and molybdenum is accelerated to increase the step lengh rapidly, The etching speed will increase rapidly.

Acetic acid (CH ₃ COOH) serves to adjust the galvanic phenomenon of copper and molybdenum, it is preferably included in 5 to 30% by weight relative to the total weight of the composition. When acetic acid is included in less than 5% by weight, the galvanic phenomenon of copper and molybdenum is increased and the step length is increased, and the etching speed of copper is large, resulting in over-etching, and when included in excess of 30% by weight, the pattern Of straightness.

When acetic acid is contained, the etching rate of copper is increased by melting the oxide film (CuO ₂ ) formed on the copper surface in the phosphoric acid solution. In the present study, the addition of acetic acid in the phosphoric acid solution caused the growth of molybdenum oxide (MoO ₂ ) on the surface of molybdenum, further reducing the etching rate of molybdenum. As the acetic acid content in phosphoric acid increases, the overall galvanic reaction is changed by the above-mentioned action, and the step length and skew are reduced.

In the present invention, in order to reduce such a galvanic effect, an imidazole is further included as an additive to existing phosphoric acid, nitric acid and acetic acid. The exact mechanism of the imidazole in phosphoric acid is unknown, but for additives such as imidazole, subsequent copper is deposited on the surface by forming complexes with copper ions and molybdenum ions adsorbed or etched on the copper or molybdenum surface. Molybdenum etch rate can be controlled. When the imidazole is contained in a certain amount or more, the etching rate of copper may be excessively suppressed, rather it may cause non-uniformity of etching.

Therefore, in the present invention, imidazole is an additive that serves as a Cu / Mo galvanic reaction controller, and it is preferable that imidazole is contained in an amount of 0.01 to 5% by weight based on the total weight of the composition. Do. More preferably the imidazole is included at least 0.1% by weight or more, particularly preferably 0.1 to 0.3% by weight. If the imidazole is contained in less than 0.01% by weight, the galvanic phenomenon of copper and molybdenum is increased so that the step length (the difference between the copper and molybdenum wiring width after etching is “step length”). In the case of containing more than 5% by weight, the etching rate of copper decreases drastically.

The solution temperature of the etchant is preferably 30 ° C to 60 ° C, particularly about 40 ° C. Non-uniformity of skew and step length occurred at solution temperature below 30 ℃, and over-etching phenomenon was observed above 60 ℃.

The thickness ratio of the copper film and the molybdenum film is preferably 30: 1 or more, and in the case below, the galvanic reaction becomes large, thereby increasing the step length. If it exceeds 30: 1, the galvanic phenomenon is reduced and the step length is reduced. 100 kPa with an optimum thickness of Mo and 3,000 kPa with an optimum thickness of Cu are preferred.

The residual stress of the molybdenum film or the molybdenum alloy film is preferably tensile stressed, and in the case of molybdenum deposited film, a galvanic phenomenon with copper when deposited under a high Ar pressure process condition This decreases, which is advantageous for forming a taper angle.

The copper film or copper alloy film is preferably annealed for 10 minutes to 1 hour at a temperature of 100 ℃ to 300 ℃ after deposition.

The etchant according to the present invention can be advantageously used for the manufacture of TFTs, active matrix OLEDs or touch sensor panels of flat panel displays.

The etchant composition of the present invention may further include conventional additives such as, for example, surfactants, etch control agents, and may further add other additives known as desired and desired etching properties.

Due to the characteristics of the molybdenum film, a small particle residue is formed and remains on the glass substrate or the lower film, which causes pixel defects. Most etchant essentially contains a fluorine compound to remove the residue. Fluorine compounds have the effect of removing residues but have the disadvantage of damaging the glass substrates due to the fluorine compounds.

On the other hand, the etchant composition according to the present invention preferably does not contain a fluorine compound added to remove the residue of Mo, because, unlike the permeate-based etchant, the problem of Mo residue almost occurs in the phosphate-based etchant such as the present invention Since no fluorine compound needs to be added to the etchant, the disadvantage of glass damage due to the fluorine compound additive is eliminated.

In addition, the present invention comprises the steps of depositing a multi-layer including at least a molybdenum or molybdenum alloy film and a copper or copper alloy film on the substrate;

Forming a photoresist film having a predetermined pattern on the multilayer;

Using the photoresist film as a mask, 50 to 80 wt% of phosphoric acid based on the total weight of the composition; Nitric acid 0.5-10 wt%; Acetic acid 5-30 wt%; 0.01-5 wt% of imidazole; And etching the multi-layer using an etchant including a residual amount of water to form metal wirings.

Removing the photoresist film;

Washing and drying the metal wires with deionized water;

It relates to an etching method of a multi-layer comprising a.

Preferably the multi-layer is molybdenum and at least one layer of copper or copper alloy, such as, for example, a Cu / Mo laminated metal film, a Cu / Mo-alloy laminated metal film, a Cu-alloy / Mo-alloy laminated metal film, or the like. Or at least one layer of molybdenum alloy.

In the etching method of the multilayer of the present invention, a molybdenum or molybdenum alloy film is deposited on the substrate, a copper or copper alloy film is deposited on the molybdenum or molybdenum alloy film, and the photoresist film is copper or copper It can be formed in the alloy film.

The molybdenum alloy may include molybdenum and preferably at least one element selected from W, Ti, Ta, and Nb. The copper alloy may include copper and at least one element preferably selected from Mg, Mo, and Mn.

Preferably, the molybdenum or molybdenum alloy film has a thickness of 100 to 500 kPa, the copper or copper alloy film may have a thickness of 1,000 to 20,000 kPa, and efficient etching may occur in this range.

In addition, the etching may be performed at a temperature of 30 ℃ to 60 ℃, preferably about 40 ℃. When using the etchant composition, it is preferable to spray the etchant on the substrate for 30 seconds to 150 seconds through a spray method (spray method) to form a metal wiring. The copper or copper alloy film may advantageously be a source / drain electrode.

The substrate is advantageously a glass substrate for a TFT LCD, a metal thin film substrate or a plastic substrate for a flexible display, and the substrate can be used for a TFT LCD, an active matrix OLED or a touch sensor panel.

The present invention relates to the use of molybdenum or molybdenum alloys with one or more layers of copper or copper alloys, including Cu / Mo laminated metal films, Cu / Mo-alloy laminated metal films, and Cu-alloy / Mo-alloy laminated metal films. Multi-layers containing more than one layer can be simultaneously etched to minimize manufacturing process, cost and time, provide excellent etching profile and etching characteristics, high stability etching liquid composition, and no damage to equipment Provides excellent productivity

Figure 1a is a step length and Figure 1b is a cross-sectional view when etching the Cu / Mo double layer using the phosphate + nitric acid + acetic acid + additive-containing etchant proposed in one embodiment of the prior art (public patent publication KR 2006-0082270 A) SEM picture.
FIG. 2A is a plan view (skew and step length) when etching a Cu / Mo double layer using an etchant including phosphoric acid, nitric acid, acetic acid, additive imidazole, and water prepared according to an embodiment of the present invention. It can be seen that greatly improved) and Figure 2b is a cross-sectional SEM photograph.
FIG. 3A illustrates a change in the etching aspect of the Cu / Mo layer according to the addition of imidazole (C ₃ H ₄ N ₂ ) as an embodiment of the present invention.
FIG. 3B illustrates a change in the etching behavior of the Cu / Mo layer by adding aminotetrazole (CH ₃ N ₅ ) instead of imidazole as an additive as a comparative example of FIG. 3A.
FIG. 3C illustrates the change in etching behavior of the Cu / Mo layer to compare the effects on the step lengths of imidazole and aminotetrazole in FIGS. 3A and 3B.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples. However, the embodiments of the present invention are intended to describe the present invention in detail and do not limit the scope of the present invention.

Preparation of the etchant composition and etching characteristic experiments were carried out as follows:

First, an etchant composition according to Comparative Example 1 and Example 1 was prepared, and the experiment was performed according to the following experimental example.

Experimental Example

Prepare a specimen on which a Cu / Mo double layer was deposited on a substrate, and put the etchant of each of Example 1 and Comparative Example 1 into a spray etching method (manufactured by FNS Tech), and warmed by setting the temperature to 40 ° C. When the temperature reached 40 ± 0.1 ° C., the substrate was etched. Total etching time was performed by giving 50% of over etching based on EPD (End Point Detection). After the substrate was etched and etched out, the substrate was etched out, washed with deionized water, dried using a hot air drying apparatus, and removed using a photoresist stripper. After washing and drying, an electron scanning microscope (SEM; manufactured by TESCAN) was used to evaluate CD (critical dimension) Skew (etching loss), step length which is a deviation between copper and molybdenum, and etching residues.

Comparative Experiment 1

As mentioned in the background art, existing copper etchant containing phosphoric acid nitric acid and other additives has been proposed in published patent publication KR 10-2009-0095408 A and published patent publication KR 10-2006-0082270 A and the like. The specific application of the etchant to the structure has not been found.

Conventional Patent Publication No. KR 2006-0082270 A, which is referred to as a comparative example, is an etching solution composition for metal electrodes for forming a thin film transistor of a flat panel display, and includes an etching rate regulator in a composition of phosphoric acid + nitric acid + acetic acid + water, which is a conventional aluminum etching solution. Further to an etchant composition which enables a desired pattern by further addition, according to Representative Example 1 of the prior art, the etchant has the following composition:

55 wt% H ₃ PO ₄ + 8 wt% HNO ₃ + 10 wt% CH ₃ COOH + (NH ₄ ) ₂ HPO ₄ 2 wt% + CH ₃ COONH ₄ 2wt% + residual H ₂ O.

An etching liquid composition having the above composition was prepared and an etching characteristic experiment was performed according to the experimental example, and the experimental results are shown in FIGS. 1A and 1B.

That is, FIG. 1A is a specific application result of Cu / Mo double layer of an etching solution containing phosphoric acid, nitric acid, acetic acid composition and additives proposed in the prior art as a comparative example (JP 2006-0082270 A). The step length and FIG. 1B that appear when the / Mo bilayer is etched shows a cross-sectional SEM image.

As shown in FIG. 1, when the phosphate-based etchant is applied to the Cu / Mo double structure, the lower layer of molybdenum is hardly dissolved due to the difference in etching rates and galvanic corrosion of the two metals, and the upper layer copper Severe overetching occurs. For convenience, the difference between the copper and molybdenum wiring widths generated at this time is called step length (see FIG. 1A). According to FIG. 1A, when the Cu / Mo double layer is etched with the etching solution according to the prior art, a considerably large step length occurs, indicating that the etching profile is poor. Also, as shown in FIG. 1B, a problem arises in that the CD (critical dimension) skew is increased (defective etching characteristic).

Example 1 (Experiment 1)

In one embodiment of the present invention,

H ₃ PO ₄ 70 wt% + HNO ₃ 2 wt% + CH ₃ COOH 15 wt% + C ₃ H ₄ N ₂ (imidazole) 0.1 wt% An etchant having a composition ratio of 12.9 wt% + H ₂ O was prepared.

FIG. 2A is a plan view (skew and step length) of etching a Cu / Mo double layer using an etchant including phosphoric acid, nitric acid, acetic acid, additive imidazole, and water prepared according to an embodiment of the present invention. Can be seen to be greatly improved) and Figure 2b shows a cross-sectional SEM image.

Referring to FIGS. 2A and 2B, the galvanic phenomenon is reduced in the Cu / Mo double layer, and the skew and step lengths are greatly improved, so that the pattern profile and the etching characteristics are excellent (that is, comparing FIGS. 1A and 2A). When the etchant of the present invention is used, it can be seen that the step length is significantly improved than when the etchant of the prior art is used. When comparing the etching solution of the present invention, FIG. 1b and FIG. Greatly improved).

The inventors have confirmed that the etching characteristics are improved through the etching characteristic experiments with the etching liquid having various compositions within the composition range of claim 1, and for reference, the etching liquid having the composition ratio of Example 1 according to the embodiment of the present invention. An etching liquid composition having the following composition ratios, in which an improvement effect almost similar to that of the etching characteristic experiment result of FIG. 2 was confirmed, is described as further examples:

Example 2

H ₃ PO ₄ 70 wt% + HNO ₃ 2 wt% + CH ₃ COOH 15 wt% + C ₃ H ₄ N ₂ (imidazole) 0.1 ~ 0.3 wt% + The rest is distilled water;

Example 3

H ₃ PO ₄ 58 wt% + HNO ₃ 2 wt% + CH ₃ COOH 20 wt% + C ₃ H ₄ N ₂ (imidazole) 0.1 ~ 0.3 wt% + The rest is distilled water;

Example 4

H ₃ PO ₄ 52 wt% + HNO ₃ 8 wt% + CH ₃ COOH 20 wt% + C ₃ H ₄ N ₂ (imidazole) 0.1 ~ 0.3 wt% + The rest is distilled water.

Figure 3a shows the change in the etching aspect of the Cu / Mo layer according to the imidazole (C ₃ H ₄ N ₂ ) addition in the etching solution according to the present invention.

Imidazole is an additive that serves as a Cu / Mo galvanic reaction controller.

For effective Cu / Mo etching, skew is less than 0.5 μm, and step length = width of copper-width of molybdenum (ie, difference in copper and molybdenum wiring width after etching) caused by the difference in etching rate between Cu and Mo The difference must be minimal.

As shown in Figure 3a it can be seen that the concentration of the step length is minimal as the imidazole is added to the phosphoric acid, nitric acid, acetic acid solution. Figure 3a can be seen that the best effect when the imidazole concentration is 0.02 M.

According to the research of the present inventors, in order to find an additive that reduces the galvanic reaction in addition to imidazole (C ₃ H ₄ N ₂ ) , aminotetrazole (CH ₃ N ₅ ), which is a heterocyclic amine compound such as imidazole, is used. Experimented with additives (see FIG. 3b), ascorbic acid (C ₆ H ₈ O ₆ ), sodium dihydrogen phosphate (NaH ₂ PO ₄ ), aminodiacetic acid Experimented with many additives such as (C ₄ H ₇ NO ₄ ) and disodium hydrogen phosphate (Na ₂ HPO ₄ ), but significantly improved skew and step length by reducing galvanic reaction as imidazole. One additive was not found.

For example, FIG. 3B shows a change in the etching behavior of the Cu / Mo layer with the addition of aminotetrazole (CH ₃ N ₅ ) belonging to a heterocyclic amine compound such as imidazole. As shown in Figure 3b, it can be seen that aminotetrazole does not significantly improve the step length as imidazole.

FIG. 3C illustrates the change in etching behavior of the Cu / Mo layer to compare the effects on the step lengths of imidazole and aminotetrazole in FIGS. 3A and 3B.

On the other hand, according to the study of the present inventors, the imidazole was found to have a significant effect on the etching rate in the permeate-based etchant, but also does not affect the etching rate in the phosphate-based etchant.

step length: difference between copper and molybdenum wiring width after etching
skew: skew
imidazole: imidazole
aminotetrazole: aminotetrazole
additive: additive

Claims (22)

Relative to the total weight of the composition,
Phosphoric acid 50-80 wt%;
Nitric acid 0.5-10 wt%;
Acetic acid 5-30 wt%;
0.01-5 wt% of imidazole; And
Etching liquid composition of a multilayer comprising a residual amount of water. The method of claim 1,
Wherein the etchant composition comprises at least 0.1 wt% of imidazole. The method according to claim 1 or 2,
Relative to the total weight of the composition,
Phosphoric acid 50-75 wt%;
Nitric acid 1-9 wt%;
Acetic acid 14-20 wt%;
Imidazole 0.1-0.3 wt%; And
Etching composition comprising a residual amount of water. The method of claim 1,
The multi-layer is formed of a molybdenum or molybdenum alloy and at least one layer of copper or copper alloy, including a Cu / Mo laminated metal film, a Cu / Mo-alloy laminated metal film, and a Cu-alloy / Mo-alloy laminated metal film. An etchant composition comprising at least one layer. 5. The method of claim 4,
The multilayer film is an etching solution composition, characterized in that the Cu / Mo double film. The method of claim 1,
The solution temperature of the etchant is an etchant composition, characterized in that 30 ℃ to 60 ℃. The method according to claim 4 or 5,
Etching composition, characterized in that the thickness ratio of the copper film and molybdenum film is 30: 1 or more. 5. The method of claim 4,
The residual stress of the molybdenum film or molybdenum alloy film is an etching liquid, characterized in that the tensile stress. 5. The method of claim 4,
The copper film or the copper alloy film is an etching solution composition, characterized in that anneal for 10 minutes to 1 hour at a temperature of 100 ℃ to 300 ℃ after deposition. The method of claim 1,
The etchant composition is an etching solution composition, characterized in that it does not contain at least one of hydrogen peroxide and fluorine compounds as a component. The method of claim 1,
Wherein the etchant is used in the manufacture of a TFT, active matrix OLED or touch sensor panel of a flat panel display. Depositing a multilayer comprising at least a molybdenum or molybdenum alloy film and a copper or copper alloy film on the substrate;
Forming a photoresist film having a predetermined pattern on the multilayer;
Using the photoresist film as a mask, 50 to 80 wt% of phosphoric acid based on the total weight of the composition; Nitric acid 0.5-10 wt%; Acetic acid 5-30 wt%; 0.01-5 wt% of imidazole; And etching the multi-layer using an etchant including a residual amount of water to form metal wirings.
Removing the photoresist film;
Etching method of a multi-layer comprising the step of washing and drying the metal wiring with deionized water The method of claim 12,
The multi-layer is formed of a molybdenum or molybdenum alloy and at least one layer of copper or copper alloy, including a Cu / Mo laminated metal film, a Cu / Mo-alloy laminated metal film, and a Cu-alloy / Mo-alloy laminated metal film. An etching method comprising at least one layer. The method of claim 12,
A molybdenum or molybdenum alloy film is deposited on the substrate, a copper or copper alloy film is deposited on the molybdenum or molybdenum alloy film, and a photoresist film is formed on the copper or copper alloy film. Etching method. The method of claim 13,
Molybdenum alloy is an etching method comprising molybdenum and at least one element selected from W, Ti, Ta, Nb. The method of claim 13,
Copper alloy is an etching method, characterized in that containing copper and at least one element selected from Mg, Mo, Mn. The method of claim 13,
The molybdenum or molybdenum alloy film has a thickness of 100 to 500 kPa, the copper or copper alloy film has a thickness of 1,000 to 20,000 kPa. The method of claim 12,
The etching is an etching method, characterized in that carried out at a temperature of 30 ℃ to 60 ℃. The method of claim 12,
The etchant is sprayed on the substrate by a spray method (spraying method) for 30 seconds to 150 seconds. The method of claim 13,
The copper or copper alloy film is an etching method, characterized in that the source / drain electrode. The method of claim 12,
The substrate is a glass substrate for a TFT LCD, a metal thin film substrate or a plastic substrate for a flexible display, and the substrate is used for a TFT LCD, an active matrix OLED or a touch sensor panel. The method of claim 2,
The etchant composition is characterized in that it comprises 0.1 to 0.3 wt% of imidazole.

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