TW201012971A - Cu or Cu/Mo or Cu/Mo alloy electrode etching liquid in liquid crystal display system - Google Patents

Abstract

The present invention relates to an etching solution for a Cu layer, a Cu/Mo layer, or a Cu/Mo alloy layer that includes, based on a total weight of the etching solution, hydrogen peroxide of 12 to 35wt%, sulfate of 0.5 to 5 wt%, phosphate of 0.5 to 5 wt%, and fluorine ion of 0.0001 to 0.5 wt%, a first water-soluble cyclic amine of 0.1 to 5 wt%, chelating agent of 0.1 to 5 wt%, a second water-soluble cyclic amine of 0.1 to 5 wt%, glycol of 0.1 to 5 wt%, and deionized water so that a total weight of the whole the etching solution is 100 wt%. The present invention relates to the etching solution of the Cu layer, the Cu/Mo layer, or the Cu/Mo alloy is used in the etching process a gate electrode that configures a thin film transistor (TFT) of the liquid crystal display device, a source electrode, or a drain electrode that used in the etching process of the metal line.

Description

201012971 ... 6. Description of the Invention: [Technical Field of the Invention] The present invention relates to etching for a copper (Cu) layer, a copper/molybdenum (Cu/Mo) layer, or a copper/molybdenum alloy (Cu/MoX) layer. Solution. [Prior Art] In a semiconductor device, in order to form a metal line on a substrate, a process of forming a metal layer by sputtering is generally performed to form a photoresist layer having a predetermined pattern on the metal layer. The process, and the use of the photoresist as a contact mask to perform an etching process. In particular, the etching process is performed by dry etching using a plasma or the like or wet etching using an etching solution. In the case of dry etching, since it requires a high vacuum or the like, the etching conditions thereof are strict and costly. Therefore, wet etching is advantageous over dry etching when a suitable etching solution is present. At the same time, in a thin film transistor liquid crystal display (TFT-LCD) device, since the resistance of the metal line layer is the main cause of the RC signal delay, the low resistance metal line layer is formed to increase the panel size and implement high resolution. The key. However, it is used as a metal wire layer in the related art (Cr, resistivity: 25><1 (Τ6 Ωιη), molybdenum (Mo, resistivity: 12x10-6 Ωιη), aluminum hydride (AINd, resistance) Coefficient: 5><1(Τ6Ωιη) and its alloy have high electrical resistance, so it is less suitable for use as a gate and data line in a large-size thin film transistor liquid crystal display (TFT-LCD). For this reason, it has a higher aluminum. Or the resistance of chrome is much lower than that of the resistor and environmentally friendly copper metal, which is used as a material for the low resistance wire layer. However, in the case of copper, it is very difficult to apply the photoresist to the metal layer. And the problem of the patterning process; for example, the adhesion between the glass substrate and the tantalum insulating layer is poor. In order to solve these problems, a copper and an intermediate metal layer have been provided at the same time, instead of the single use of copper in 201012971 alone. The technique is to increase the adhesion between the copper layer and the glass substrate or the germanium insulating layer and inhibit the diffusion of copper into the germanium layer, wherein the intermediate metal layer may include titanium, indium alloy, etc. For use in wet etching In order to etch the copper/intermediate metal layer, it is necessary to develop a suitable etch solution, but a suitable etching solution for performing etching has not been developed so far. For example, Korean Patent Application Laid-Open No. 1999-017836 A method of etching a copper/molybdenum layer using phosphoric acid, nitric acid, and acetic acid is disclosed. However, the method not only has a too fast etching rate, but also has a taper angle of an etch β profile as shown in FIG. The taper angle is equal to or greater than 90. Therefore, it has poor pattern straightness and it is difficult to carry out the subsequent process. Further, in order to etch a copper/titanium (Cu/Ti) layer, attempts have been made to use fluorine. Ion etching solution, but in general, if the etching solution contains fluorine ions, it is known to affect the glass substrate and the tantalum nitride layer, etc., thereby causing various defects. In addition, most of the copper etching using hydrogen peroxide is used. The invention of the solution discloses an etching solution for a copper/molybdenum layer comprising an organic acid, hydrogen peroxide, a sulfate, a cyclic amine compound, and deionized water. Pattern straightness and relatively satisfactory taper angle, but since these inventions should contain organic acids as essential components, they are not good in terms of aging variation. Meanwhile, Korean Patent Application No. 2 〇〇6·0〇99〇89 discloses a solution for the copper/copper layer containing hydrogen peroxide, sulfate, phosphate, fluoride, water-soluble cyclic amine compound, chelating agent and deionized Water. In this case, it can be easily controlled by controlling the etching rate, uniformly obtaining the desired taper, obtaining excellent straightness, making the CD loss small, and causing no residue, so that it can be used for manufacturing. A copper/flip layer liquid crystal display device is used, but its disadvantage is that the aging variation according to the change of the metal ion concentration 201012971 is severe, in particular, the rapid decomposition reaction of hydrogen is increased, so the paste dissolves due to a large amount of copper ions. In particular, according to the research of the inventor of the present case, the qualitative reduction is ##. (For example, copper, turn, etc.) The oxidant's surname solution ^ When using hydrogen peroxide as the metal process, (4) The gold concentration in the solution >1 ion concentration will be *clear /: JLt 'When the residual system is used as a The horn ions (e.g., copper) that decompose the hydrogen peroxide catalyst cause aging variations throughout the etching process. Hydrogen peroxide is the first to be oxidized. As can be seen from the serious examples, it will lead to the aging change of the surname process and the slow decomposition of the liquid helium temperature and the expansion of the pipeline system due to the volume expansion of the gas. Rise, smoke, and explosion are destroyed. Therefore, the metal concentration should be completely controlled in terms of environment/safety. SUMMARY OF THE INVENTION The present invention discloses a copper/molybdenum according to the present invention, and aims to provide a solution of a kind (4) which is carried out on a metal wire made of steel and a copper/pin alloy - a single step secret _ to ensure Insect all the characteristics of the solution, suppress the decomposition reaction of hydrogen peroxide associated with the increased metal ion wave duration during the process, maintain the (four) characteristics for a long time, and counteract the decomposition reaction. (4) Newly simplified phase The problem of etching solutions of molybdenum or copper/pin alloys. In order to achieve the above object, an etching solution for a metal wire according to the present invention comprises: the (four) liquid (four) comprising hydrogen peroxide, a sulfate, a salt, a fluoride ion-providing fluoride, a water-soluble cyclic amine compound, The integrator, the second water-soluble cyclic aminated sigma, the alcohol compound, and deionized water solve the problems of the etching solution in the related art. 201012971 [Embodiment] Hereinafter, an etching solution according to the present invention and a method of using the etching solution to etch a metal wire will be described in more detail. The metal wire according to the present invention is a copper layer, a copper/key layer, or a copper/box alloy layer. The 'copper/germanium layer or the copper/over alloy layer may be a plurality of layers, wherein at least one copper layer, at least one molybdenum layer, and/or a molybdenum-alloy layer are laminated to each other, wherein the plurality of layers may include a copper/ Molybdenum (molybdenum-alloy) double layer 'copper / molybdenum (molybdenum - alloy) / copper or molybdenum (molybdenum - alloy) / copper / molybdenum (alloy) three layers. The order of the layers can be appropriately controlled depending on the material and adhesive properties of the substrate. Ο The molybdenum alloy may be composed of molybdenum-tungsten (M〇-w), molybdenum-titanium (Mo-Ti), molybdenum-niobium (Mo-Nb), turn-chromium (Mo-Cr), or turn-turn (Mo-Ta). Composition p relates to an etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer, comprising hydrogen peroxide, a sulfate, a phosphate, a fluoride providing a fluoride ion, a chelating agent, The first water-soluble cyclic amine, the second water-soluble cyclic amine, the diol compound, and deionized water. The sulfate may be selected from at least one of ammonium sulfate, ammonium persulfate, sodium sulfate, sodium persulfate, sulfuric acid unloading, cesium persulfate, and sulfuric acid, but not limited thereto, the sulfate increases the etching rate of the steel, Effectively increase the productivity of the etching process. Phosphate is not greatly limited, but may be selected from at least one of ammonium monophosphate, bisulphate, potassium dihydrogenate, and sodium dibasic phosphate. In addition, the fluoride may be used as a substrate for argon I acid which can provide fluorine ions in the etching solution, and is preferably selected from at least hydrofluoric acid, ammonium fluoride, ammonium hydrogen fluoride, potassium fluoride, and potassium hydrogen fluoride. One. When etched the copper/molybdenum layer or the copper/molybdenum alloy layer, the sulphate acts as a surface layer that avoids the lower portion or the 19-alloy layer is excessively engraved on the lower portion of the copper layer. Here, when there is an excessive amount of the cuprate, the lower surface layer or the molybdenum-alloy layer is protruded from the top of the copper 201012971 ' ^ and has a double profile ' and promotes the purification of the surface layer or the indium alloy layer. -: '丨 action' such as a residue of a molybdenum layer or a molybdenum-alloy layer. When the lye salt is removed, the tumbling or alloying layer is excessively closed, thereby forming the base of the ___ alloy layer (unde coffee) or double (four) copper. ° is selected from the group consisting of hydrofluoric acid, fluorinated money, hydrogenated hydrogen, potassium fluoride, and potassium hydrogen fluoride. ^ The system is responsible for removing the role of the residue, which is formed by partial passivation of the metal properties of the cloud in the indium layer or the σ gold layer. When a hydrogen peroxide key layer or a molybdenum alloy layer is used, a problem of residue occurs due to a partial passivation reaction of the layer. The reason is that indium hexoxide (Μο〇6) formed by hydrogen peroxide self-deuterium is completely _ under low pH (for example, below pH 6.g), and since the surface is passivated, it cannot be positively bivalent. The form of (Mq + 3) or the positive hexavalent pin (he + 6) transitions to form a residue. However, when a fluoride having a fluoride ion is added to the etching solution, the highly active fluoride ion promotes an etching reaction of molybdenum trioxide so that etching can be performed without forming a residue of molybdenum. In particular, when a fluoride is used together with a residual system composed of hydrogen peroxide, a sulfate, and a dish salt, there is little problem of etching of the protective layer (for example, tantalum nitride, etc.) of the glass layer. Therefore, it is very helpful to form a pattern of metal lines. The chelating agent is not particularly limited, and is preferably selected from the group consisting of ethylenediamine tetraethylene (EDTA), imine diacetic acid, nitrilotriacetic acid, and diethylene triamine pentaacetic acid. , at least one of DTPA). When the ion concentration of the copper layer, the molybdenum layer or the molybdenum alloy layer in the etching solution is increased, the integrator prevents a phenomenon of lowering the etching ability of the etching solution, and (the integrator) 201012971 suppresses occurrence when the etching solution is stored The hydrogen peroxide itself/more specifically, in the case of a preferred embodiment of the chelating agent, the metal ions generated by the surname of the copper layer are blocked by the chelation reaction. To inhibit the decomposition reaction of peroxidation gas. Therefore, although the performance does not change when a large number of metal lines are etched.

❹ In the present invention, the first water-soluble cyclic amine is not greatly limited, but is selected from the group consisting of amine tetrazole, benzotriazole, methylbenzotriazole, 1,2,3-triazole, imidazole, At least one of hydrazine, hydrazine, pyrazole, pyridine, pyrimidine, pyrrole, and pro-amino acid. The first water soluble cyclic amine controls the etch rate of copper and enhances the straightness of the line. The second water-soluble cyclic amine may be selected from at least one of cyclohexylamine, cyclopropylamine, cyclopentylamine, cycloheptylamine, and cyclooctylamine. Further, the second water-soluble cyclic amine suppresses the decomposition reaction of hydrogen peroxide associated with the increased metal ion concentration during the remnant process to maintain the etch characteristics for a long period of time, thereby stabilizing the etching solution according to the present invention against the decomposition reaction. When a diol is added to the second water-soluble cyclic amine, its stability can be further improved. The diol is selected from at least one of ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, hexanediol, butanediol, polyethylene glycol, and polypropylene glycol, and is more than the second water-soluble cyclic amine A lot of injection. When a second water-soluble cyclic amine is added in an amount larger than the diol, a residue of molybdenum is produced. The etching solution according to the present invention is as follows: The present invention relates to a etch solution for a copper layer, a copper/flip layer, or a copper/gu alloy layer, comprising 12 to the total weight of the etching solution, 35% by weight of hydrogen peroxide, 0.5 to 5% by weight of sulfate, 55 to 5% by weight of the acid salt, and 0,0001 to 0.5% by weight of fluoride ion-providing fluoride, 0.1 to 5 % by weight of the first water-soluble cyclic amine, 0.1 to 5 parts by weight. The chelating agent, 1.1 to 5% by weight of the second water-soluble ring 9 201012971 amine, 0.1 to 5% by weight of the diol, and deionized water, so that the total weight of the etching solution is 100% by weight. Further, the characteristics of the etching solution are maintained within this range for a long period of time, and may have an appropriate etching rate, and the etching solution may be a stable solution by utilizing etching and no residue decomposition reaction. And the line has good straightness. The hydrogen peroxide, sulfate, phosphate, fluoride, first water-soluble cyclic amine, and chelating agent for the etching solution of the metal wire according to the present invention may be those conventionally used in the conventional method, and preferably have The purity required for semiconductor manufacturing. Further, the deionized water used for the etching solution is used in a semiconductor process, and water of 18 Ω / cm or more is preferably used. The etching solution of the copper layer, the copper/la layer, or the copper/key alloy layer is used for etching the gate electrode, the source electrode, or the source/drain electrode of the thin film transistor (TFT) of the liquid crystal display device. In the process, the etching process for metal lines. Furthermore, the present invention relates to a method of etching a metal wire, comprising: depositing a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy film on a substrate; forming a photoresist layer having a predetermined pattern on the substrate Using the etching solution, a metal wire is formed on the film formed by the photoresist; the photoresist layer is removed; and the metal wire is cleaned with deionized water and dried with nitrogen or air. In the metal wire, the copper/molybdenum layer or the copper/molybdenum alloy layer is a plurality of layers, wherein at least one copper layer, at least one molybdenum layer, and/or a molybdenum-alloy layer are laminated to each other, wherein the molybdenum layer is deposited or The molybdenum-alloy layer is to a thickness of 100 to 500 angstroms, and the copper layer is deposited to a thickness of 1000 to 10,000 angstroms, and the etching can be effectively carried out without residue. The etching process temperature for forming the metal lines is not greatly limited, but can be performed at 30 to 40 C ° 201012971. When the Lai (4) is used, the impregnation method and the spray can be carried out, but it is preferred to dissolve the (4) on the substrate by means of blasting, so that the etching process can be performed and sprayed onto the substrate by spraying. It takes 30 to 16 seconds to form a metal wire. Further, when the photoresist is removed, a generally used release agent can be used, but not limited thereto. When the metal wire is etched using the etch solution according to the present invention, the following effects can be obtained. First, the etching rate of the etching solution according to the present invention is freely controlled by the change of the composition of the etching solution, the etching profile is excellent, and the straightness of the line is good. In addition, the residue can be completely removed, and thus can be used as an etching solution when used as a gate electrode having a low resistance as a gate electrode and a source/drain electrode of a thin film transistor liquid crystal display (TFT-LCD). . Secondly, although a large amount of the metal layer is etched by the etching solution according to the present invention, the characteristics of the buttoning solution can be maintained, and the storage period of the #etching solution is long. In addition, the concentration of copper and molybdenum metal increased with the etching process does not cause rapid decomposition of hydrogen peroxide at 4,000 ppm, so that a stable process operation can be performed. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to specific embodiments and comparative examples. The description below is intended to provide a clear understanding of the invention and is not intended to limit the scope of the invention. [Examples and Comparative Examples] Preparation of etching solutions The etching solutions of the first to sixth embodiments and the first to fourth comparative examples were prepared by mixing the contents and compositions shown in Table 1 below. Etching method 201012971 depositing an indium layer (200 angstroms) on a glass substrate (10 mm mm), depositing a copper layer (1600 angstroms) on the indium layer (2 angstroms) and passing through a photoresist process Forming - a photoresist having a predetermined pattern on the substrate. Thereafter, the solution processes of Examples 1 to 6 and Comparative Examples 1 to 4, respectively, were carried out on the -copper/(tetra) layer, respectively. The condition in the (10) m process is that the temperature system is 3 generations, and the in-service process is carried out by spray spraying the solution on the substrate for just two seconds. After the balance, the wire was removed with _ agent, cleaned with ionized water alone, and dried with nitrogen. Evaluation of etching characteristics The evaluation of the characteristics of the samples by the method is shown in Table 2 below. The evaluation of the characterization characteristics was carried out in a good or poor manner by observing (10) m by the surname method and observing the cross section of the side profile of the copper/(four) layer using a scanning electron microscope. The evaluation is described in Table 2 below. The evaluation of the molybdenum residue is described in Table 2 below, which is carried out by the method of (4), and the cross section of the etching profile of the copper/turned double layer is observed using a scanning electron microscope or an optical microscope to evaluate the molybdenum residue. Exist or not. According to the stability evaluation of the etching solution, a weight ratio of 1 〇: i © was added to the solution of the examples and the comparative examples at room temperature, and the temperature change was observed for 72 hours to determine that the temperature did not exceed 40. The reason for this is that the rapid decomposition reaction of hydrogen peroxide involves an increase in temperature. The stability evaluation of the etching solution can be expressed by the maximum stability of copper, and the maximum stability of copper is measured by the maximum concentration of copper (ppm), and the temperature does not exceed 40 when the stability is evaluated by the above method. (:. 12 201012971 Table 1 Hydrogen peroxide (% by weight) Ammonium sulfate (% by weight) Ammonium monophosphate (% by weight) Aminotetrazole (% by weight) EDTA (% by weight) Hydrofluoric acid (% by weight) Cyclohexylamine (% by weight) Polyethylene glycol (% by weight) Deionized water (% by weight) First Embodiment 21.5 1 1.5 1 1.5 0.05 0.1 0.1 73.25 Second Embodiment 21.5 1 1.5 1 1.5 0.05 0.3 0.3 72.85 ί Third Embodiment 21.5 1 1.5 1 1.5 0.05 0.5 0.5 72.45 Fourth embodiment 21.5 1 1.5 1 1.5 0.05 1.0 1.0 71.45 Fifth embodiment 21.5 1 1.5 1 1.5 0.05 5.0 5.0 63.45 Sixth k embodiment 21.5 1 1.5 1 1.5 0.05 0.5 1.0 71.95 t First Comparative Example 21.5 1 1.5 1 1.5 0.05 0.3 0 73.15 First Comparative Example 21.5 1 1.5 1 1.5 0.05 0 0.3 73.15 Third Comparative Example 21.5 1 1.5 1 1.5 0.05 0 0 73.45 Fourth Comparative Example 21.5 1 1.5 1 1.5 0.05 1.0 0.5 71.95 13 201012971 Table 2 Tactile rate (A/sec) Etching characteristics Molybdenum residue Copper maximum stability (ppm) Copper-molybdenum First embodiment 70-100 8-13 Good no 3,200 Second embodiment 70-100 8 -13 Good without 4,000 Third embodiment 70-100 8-13 Good No 4,200 Fourth Embodiment 70-100 8-13 Good No 4,200 Fifth Embodiment 60 to 80 8-13 Good No 4,200 Sixth Embodiment 70-85 8-13 Good No 4,200 First Comparative Example 70-100 8 -13 Good No 3,100 Second Comparative Example 70-100 8-13 Good No 2,700 Third Comparative Example 70-100 8-13 Good No 2,500 Fourth Comparative Example 70-100 8-13 Good generation 4,200 According to the result of etching characteristics, Compared with the first to third comparative examples, although the copper concentration is increased by additionally adding copper and molybdenum, the case of this embodiment does not cause a rapid decomposition reaction of hydrogen peroxide, thereby achieving stable use. When a large amount of cyclohexylamine is used, which is more than polyethylene glycol, a molybdenum residue occurs. Fig. 1 is a photograph showing a cross section of a copper/key double layer of a copper/key double layer using a scanning electron microscope when an etching solution of mixed phosphoric acid, nitric acid, and acetic acid according to Korean Patent Application Laid-Open No. 1999-017836 was used. Fig. 2 and Fig. 3 are photographs showing a cross section of an etching profile of a copper/molybdenum double layer observed by a scanning electron microscope when the etching solution according to the first embodiment was carried out. A person skilled in the art will be aware of the concepts and specific embodiments disclosed in the foregoing description, and may be readily utilized as a basis for modification or design of other specific embodiments for the same purpose. Those skilled in the art will be able to understand the embodiments of the present invention without departing from the spirit and scope of the invention as set forth in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an observation of a copper/molybdenum double layer etching profile using a scanning electron microscope when an etching solution of phosphoric acid, nitric acid and acetic acid mixed according to Korean Patent Application No. 1999-017836 is used. A photo of the section. Fig. 2 and Fig. 3 are photographs showing the cross section of the etching profile of a copper/molybdenum double layer using a scanning electron microscope when the etching solution according to the first embodiment is carried out. [Main component symbol description] (none) 15

Claims (1)

201012971 VII. Patent application scope: 1. An etching solution for copper layer, copper/molybdenum layer or copper/molybdenum alloy layer, containing hydrogen peroxide, sulfate, phosphate, fluoride ion providing fluoride, chelating agent a first water-soluble cyclic amine, a second water-soluble cyclic amine, a diol compound, and deionized water. 2. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 1, wherein the sulfate is selected from the group consisting of ammonium sulfate, ammonium persulfate, sodium sulfate, sodium persulfate, At least one of potassium sulfate, potassium persulfate, and sulfuric acid. 3. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 2, wherein the phosphate is selected from the group consisting of ammonium monophosphate, ammonium diphosphate, potassium dihydrogen phosphate, and At least one of sodium dihydrogen phosphate. 4. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 3, wherein the fluoride is selected from the group consisting of hydrofluoric acid (fluoric acid), ammonium fluoride, and hydrogen fluoride. At least one of a fluorinated clock and a hydrogen fluoride clock. 5. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 4, wherein the chelating agent is selected from the group consisting of ethylenediaminetetraacetic acid (EDTA), imine diacetic acid, At least one of nitrilotriacetic acid and diethylene triamine pentaacetic acid (DTPA). 6. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 5, wherein the first water-soluble cyclic amine is selected from the group consisting of aminotetrazole, benzotriazole, At least one of 曱基笨三三, 1,2,3-三嗤, imi, 吲哚, 嘌吟, β 嗤, D than bite, pyrimidine, pyrrole, and pro-amino acid. 7. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 6, wherein the second water-soluble cyclic amine is selected from the group consisting of cyclohexylamine, cyclopropylamine, and cyclopentylamine. At least one of cycloheptylamine and cyclooctylamine. 201012971 8. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 7, wherein the diol is selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, and dipropylene. At least one of difer, hexanediol, butanediol, polyethylene glycol, and polypropylene glycol is injected in an amount greater than the second water-soluble cyclic amine. 9. The etching solution for a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy layer according to claim 8, wherein the copper/molybdenum layer or the copper/molybdenum alloy layer is a plurality of layers, at least one of which The copper layer, at least one molybdenum layer, and/or the molybdenum-alloy layer are laminated to each other. 10. The etching beta solution for copper layer, copper/molybdenum layer, or copper/molybdenum alloy layer according to claim 9, wherein the multilayer layer comprises a copper/molybdenum (molybdenum-alloy) double layer, copper/molybdenum Three layers of (turn-alloy)/copper or molybdenum (molybdenum-alloy)/copper/molybdenum (alloy), the order of which can be appropriately controlled according to the material and adhesive properties of the substrate. U. The etching solution for the copper layer, the copper/molybdenum layer, or the copper/molybdenum alloy layer described in Item 9 > The molybdenum alloy in Moshan-dan is made of molybdenum-tungsten (Mo-W) , consisting of molybdenum-titanium (Mo-Ti), sharpening (Mo-Nb), molybdenum-chromium (Mo_Cr), or smoke-knock (Mo-Ta). 17 201012971 An etching solution of a molybdenum alloy layer, wherein the etching solution of the copper layer, the copper/molybdenum layer, or the copper/molybdenum alloy layer is used for assembling a gate electrode and a source electrode of a thin film transistor (TFT) of a liquid crystal display device In the etching process of a drain electrode or a drain electrode, it is used for an etching process of a metal line. A method of etching a metal wire, comprising: depositing a copper layer, a copper/molybdenum layer, or a copper/molybdenum alloy film on a substrate; forming a photoresist layer having a predetermined pattern on the substrate; The etching solution according to any one of claims 1 to 11, wherein a metal wire is formed on the film formed by the photoresist; © removing the photoresist layer; and cleaning the metal wire with deionized water, and Dry with nitrogen or air. 15. The method of claim 14, wherein the copper/molybdenum layer or the copper/metal alloy layer is a plurality of layers, wherein at least one copper layer, at least one germanium layer, and/or molybdenum is present in the metal line. - The alloy layers are laminated to each other. 16. The method of claim 15, wherein the molybdenum layer or the molybdenum-alloy layer is deposited to a thickness of from 100 to 500 angstroms and the copper layer is deposited to a thickness of from 1000 to 10,000 angstroms. 18