Etching solution composition and etching method

Abstract

To provide an etching solution composition that imparts a good etched surface shape to a metal to be etched at a controlled etch rate.SOLUTION: The present invention relates to an etching solution composition that contains (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a halogen compound, and (E) water.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an etching solution composition and an etching method using the etching solution composition. [Background technology]

[0002] In recent years, electronic devices have made remarkable progress in increasing the speed and capacity of their memory devices, and in particular, memory capacity has been increased by adopting a three-dimensional structure, such as 3D NAND flash memory, in which memory elements are stacked vertically from a silicon surface. Because the capacity of 3D NAND flash memory depends on factors such as the number of layers stacked, further increases in the number of layers are currently being investigated.

[0003] However, current 3D NAND flash memories use tungsten for the gate thin film, which raises concerns about signal delays due to the thinning of each layer, which aims to suppress the increase in vertical dimension caused by an increase in the number of stacked layers. To overcome this concern, it is thought that the resistance of the gate thin film material can be reduced, and in the next generation, studies are being conducted to replace the gate thin film material from tungsten electrodes with molybdenum (Mo) electrodes. To manufacture 3D NAND flash memories using molybdenum electrodes and with high-aspect-aspect structures (very large number of stacked layers), an etchant capable of precisely creating the desired three-dimensional structure is required.

[0004] Patent Document 1 discloses a method for manufacturing a touch panel sensor, which includes a step of selectively etching Al, Al alloy, Ag, or Ag alloy in a predetermined pattern using an etching solution for a metal layer containing water, phosphoric acid, nitric acid, and acetic acid. Patent Document 2 discloses a liquid composition for etching copper or a metal compound containing copper as a main component formed on IGZO, the liquid composition comprising (A) hydrogen peroxide, (B) a fluorine atom-free acid, (C) one or more compounds selected from the group consisting of phosphonic acids, phosphoric acid esters, 1H-tetrazole-1-acetic acid, 1H-tetrazole-5-acetic acid, and 4-amino-1,2,4-triazole, and (D) water. Patent Document 3 discloses a liquid composition for etching copper or a copper-based metal compound formed on IGZO, which comprises (A) hydrogen peroxide, (B) a fluorine-free acid, (C) a fluorine ion source, (D) one or more compounds selected from the group consisting of aminotri(methylenephosphonic acid), N,N,N',N'-ethylenediaminetetrakis(methylenephosphonic acid), diethylenetriaminepenta(methylenephosphonic acid), bis(hexamethylene)triaminepenta(methylenephosphonic acid), and pentaethylenehexamineocta(methylenephosphonic acid), (E) a hydrogen peroxide stabilizer, and (F) water. Patent Document 4 discloses an etching solution composition containing nitric acid and water for simultaneously etching a tungsten film and a titanium nitride film. Patent Document 5 discloses an etching solution suitable for both tungsten-containing metals and TiN-containing materials, which contains an oxidizing agent, a fluorine-containing etching compound, an organic solvent, a chelating agent, a corrosion inhibitor, and a surfactant.

[0005] Patent Document 6 discloses an etching solution composition comprising hydrogen peroxide, an etching inhibitor, a chelating agent, an etching additive, an oxide semiconductor protecting agent, and a pH adjuster, wherein the oxide semiconductor protecting agent is contained in an amount of 0.1 to 3 wt % based on the total weight of the composition. Patent Document 7 discloses an etching solution composition used for etching a metal film having at least one thin metal layer of molybdenum or a molybdenum alloy, which contains phosphoric acid, nitric acid, a polyalkylene polyamine containing three or more amino groups in one molecule, and water. Patent Document 8 discloses a method for forming a conductive pattern, which includes forming a first conductive layer and a second conductive layer on a substrate, wherein the first conductive layer is titanium nitride and the second conductive layer is tungsten, and the first conductive layer and the second conductive layer are etched using an etchant composition containing phosphoric acid, nitric acid, an auxiliary oxidant, and water (wherein hydrogen peroxide, acetic acid, hydroxide, and hydrofluoric acid are not present in the etchant composition), and the etchant composition has substantially the same etching rate for the metal nitride and the second metal. Patent Document 9 discloses a method for etching a metal barrier layer and a metal layer formed on a substrate, the method using an etching solution composition containing a predetermined oxidizing agent, an etching inhibitor containing a compound represented by formula (I), and a predetermined metal oxide solubilizer. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-164079 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-108659 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-111342 [Patent Document 4] Japanese Patent Application Publication No. 2018-006715 [Patent Document 5] Japanese Patent Application Publication No. 2019-165225 [Patent Document 6] Japanese Patent Application Laid-Open No. 2019-165240 [Patent Document 7] Japanese Patent Application Laid-Open No. 2013-237873 [Patent Document 8] US 2015 / 0200112A1 [Patent Document 9] US 11,028,488 B2 Summary of the Invention [Problem to be solved by the invention]

[0007] Thus, although various etching solution compositions have been developed, there is a demand for an etching solution composition that can form better patterns. Therefore, in view of the above-mentioned conventional problems, an object of the present invention is to provide an etching solution composition that can provide a good etched surface shape at a suppressed etching rate for a metal to be etched. Another object of the present invention is to provide a method for producing the etching solution composition and an etching method using the etching solution composition. [Means for solving the problem]

[0008] The present inventors have found that an etching solution composition containing (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a halogen compound, and (E) water can provide a good etched surface shape at a suppressed etching rate for a metal to be etched, and as a result of further research, have completed the present invention.

[0009] That is, the present invention relates to the following. [1] An etching solution composition, An etching solution composition comprising (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a halogen compound, and (E) water. [2] (D) The etching solution composition according to [1], wherein the concentration of the halogen compound is higher than 0.05 M based on the etching solution composition. [3] The etching solution composition according to [1] or [2], further comprising (F) 1-hydroxyethane-1,1-diphosphonic acid. [4] The etching solution composition according to any one of [1] to [3], wherein (D) the halogen compound is a chloride. [5] The etching solution composition according to any one of [1] to [4], which does not contain a peroxide. [6] The etching solution composition according to any one of [1] to [5], which is used for etching molybdenum or a metal containing molybdenum. [7] The etching liquid composition according to any one of [1] to [6], for forming a pattern having a three-dimensional structure. [8] A method for forming a recess, the method comprising a step of treating with the etching solution composition according to any one of [1] to [7]. [9] An etching method using the etching solution composition according to any one of [1] to [7], wherein the temperature of the etching solution composition is 15°C to 50°C. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide an etching solution composition that can provide a good etched surface shape at a controlled etching rate for a metal to be etched.

[0011] In particular, when the etching solution composition of the present invention is used in the production of a 3D NAND flash memory in which a large number of gate thin films containing molybdenum and insulating films are alternately stacked, even when the aspect ratio of the unit cell is large, the gate thin film can be etched with a substantially uniform recess amount (etching amount) throughout the entire unit cell, and the shape of the surface of the gate thin film after etching is also good. That is, the composition of the present invention contains a predetermined water concentration, and therefore not only provides a good etched surface shape, but also enables etching of the upper and lower layers of a multilayer laminate with a substantially uniform recess amount (etching amount). Furthermore, by adjusting the content of acetic acid and the like, it is possible to avoid the composition of dangerous materials under the Fire Service Act. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic diagram of a substrate to be etched. [Figure 2]FIG. 2 shows (i) a schematic diagram of the etched test substrate, and (ii) an enlarged schematic diagram of the pair of the gate thin film and insulating film after the etching process. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present invention will be described in detail below based on preferred embodiments of the present invention. The etching solution composition of the present invention is an etching solution composition containing (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a halogen compound, and (E) water. This etching solution composition makes it possible to provide a good etched surface shape to a metal to be etched at a suppressed etching rate.

[0014] In this specification, the unit "M" means "mol / L." In this specification, the numerical range "a to b" means "not less than a and not more than b."

[0015] The etching solution composition of the present invention contains (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a halogen compound, and (E) water. (A) Nitric acid is a component that oxidizes the metal to be etched and contributes to dissolution. The content of (A) nitric acid is not particularly limited, but from the viewpoint of smoothing the surface profile, it is preferably more than 2.00 M based on the etching solution composition. It is more preferably more than 2.00 M but not more than 4.00 M, and even more preferably 2.50 to 3.50 M.

[0016] (B) Acetic acid is a component that contributes to reducing the water concentration in the etching solution composition. The content of (B) acetic acid is not particularly limited, but from the viewpoint of avoiding a hazardous composition, it is preferably 8.0 M or less, more preferably 7.8 M or less, and even more preferably 7.6 M.

[0017] (C) Nitrilotris(methylene phosphonic acid) is believed to be adsorbed onto the metal surface to be etched and to inhibit the dissolution reaction without changing the water concentration. Nitrilotris(methylene phosphonic acid) is also referred to as NTMP in this specification. The content of (C) nitrilotris(methylenephosphonic acid) is not particularly limited, but is preferably 0.1 to 1.2M, more preferably 0.1 to 1.0M, and even more preferably 0.1 to 0.8M.

[0018] (D) The halogen compound is thought to form a complex with the metal to be etched or its oxide. Examples of the halogen compound include fluoride, chloride, bromide, iodide, and astatine. Fluorides are preferably HF and NHF. Chlorides are preferably HCl, NHCl, KCl, and NaCl. Bromides are preferably HBr and NHBr. Iodides are preferably HI and NHI. Preferably, the halogen compound is a chloride. The content of the (D) halogen compound is not particularly limited, but is preferably more than 0.05 M based on the etching solution composition, particularly preferably 0.06 to 1.00 M, more preferably 0.06 to 0.80 M, and even more preferably 0.06 to 0.50 M, from the viewpoints of the etched surface shape, the upper layer / lower layer ratio, etc.

[0019] (E) Water is used as a solvent in the etching solution composition. The content of (E) Water is not particularly limited, but is preferably lower than 24.0 M, more preferably 19.0 to 23.9 M, and even more preferably 19.5 to 23.5 M.

[0020] The etching solution composition of the present invention may further contain (F) 1-hydroxyethane-1,1-diphosphonic acid. 1-Hydroxyethane-1,1-diphosphonic acid is also referred to as HEDP in this specification. The content of (F) 1-hydroxyethane-1,1-diphosphonic acid is not particularly limited, but from the viewpoint of suppressing the etching rate, it is preferably 0.35 to 1.20 M, more preferably 0.35 to 1.00 M, and even more preferably 0.35 to 0.80 M.

[0021] The etching solution composition of the present invention may contain any optional component in addition to the above-mentioned components, as long as the optional component does not interfere with the etching treatment of the target metal. Examples of the optional component that can be used in the present invention include an organic solvent and a surfactant.

[0022] In one embodiment, the etching solution composition of the present invention preferably does not contain a peroxide.In one embodiment, the etching solution composition of the present invention preferably does not contain hydrogen peroxide.

[0023] The metal to be etched by the etching solution composition of the present invention is preferably molybdenum or a metal containing molybdenum.

[0024] The reason why the use of the etching solution composition of the present invention makes it possible to provide a good etched surface shape at a suppressed etching rate for a metal to be etched is not clear, but the following mechanism is thought to be the cause.

[0025] For example, when etching molybdenum using an etching solution containing phosphoric acid, nitric acid, and acetic acid, the reaction is thought to proceed according to the following chemical formula: (1) Mo + 2HNO3 → MoO2 + NO2 + NO + H2O (2) MoO2 + HNO2 → MoO3 + HNO (3) 12MoO3 + H3PO4 + 6H2O → H3PMo 12 O 40 6H2O

[0026] As shown in the formula above, the dissolution of molybdenum ultimately requires a reaction with water, so a decrease in the water concentration makes formula (3) the rate-limiting factor, which is thought to result in a suppression of the etching rate. Regarding smoothing the surface profile after etching, molybdenum exists in various oxidation states, and some compounds are readily soluble in nitric acid, water, etc., while others are not. When molybdenum in various oxidation states with different solubilities in nitric acid, water, etc. is mixed, the smoothness of the surface profile after etching tends to be impaired. In contrast, NTMP physically adsorbs onto the molybdenum surface to be etched, forming a film. By dissolving the film together with the film, it is possible to dissolve molybdenum in different oxidation states relatively uniformly, resulting in a smooth surface profile.

[0027] Furthermore, it is believed that the inclusion of a halogen compound in the etching solution composition can promote the physical adsorption of NTMP, thereby making it possible to significantly suppress the etching rate. The present invention also relates to a method of forming an etchant comprising treating with an etchant composition according to the present invention.

[0028] The etching solution composition of the present invention is preferably used to form a pattern having a three-dimensional structure. The etching solution composition of the present invention can provide a good etched surface profile at a suppressed etching rate, particularly for molybdenum or molybdenum-containing metals. This makes it possible to precisely create a pattern having a three-dimensional structure when manufacturing a 3D NAND flash memory using a gate thin film containing molybdenum and having a high aspect ratio structure (a very large number of layers). A preferred embodiment of the present invention will now be described in detail with reference to the schematic diagram of a substrate to be etched shown in FIG.

[0029] The etching solution composition of the present invention is preferably used for manufacturing a 3D NAND flash memory from a substrate formed by alternately stacking thin gate films (word lines) (3) and insulating films (thin film element isolation between cells) (4) in a direction perpendicular to a Si substrate (2). The etching solution composition of the present invention is suitable for manufacturing 3D NAND flash memories, particularly those with high stacking density or high aspect ratios of unit cells 1. For example, when stacking 128 flash memories vertically, at least 128 pairs of gate thin films 3 and insulating films 4 are formed.

[0030] When the etching solution composition of the present invention is used to manufacture a 3D NAND flash memory, the target to be etched is the gate thin film (3) of a film in which gate thin films (word lines) (3) and insulating films (thin film isolating elements between cells) (4) are alternately stacked in the direction perpendicular to the Si substrate (2).

[0031] Although the gate thin film (3) is mainly composed of molybdenum, it may, of course, also contain other metals such as aluminum, magnesium, calcium, etc. Furthermore, the gate thin film (3) preferably contains 80% by weight or more of molybdenum, more preferably 90% by weight or more, and even more preferably 95% by weight or more. The thickness of the gate thin film (3) is preferably 100 to 7000 Å, more preferably 200 to 1000 Å, and even more preferably 200 to 500 Å.

[0032] Examples of the insulating film (4) include an SiO2 film and an Si3N4 film, and the film thickness of the insulating film (4) is preferably 100 to 7000 Å, more preferably 200 to 1000 Å, and even more preferably 200 to 500 Å.

[0033] When the etching solution composition of the present invention is used in the manufacture of a 3D NAND flash memory, it is particularly preferred to target a memory having a high number of gate thin films (3) and insulating films (4). Specifically, a memory having 64 or more pairs of gate thin films (3) and insulating films (4) stacked is preferred, more preferably 128 or more pairs, and even more preferably 200 or more pairs.

[0034] The etching target preferably used with the etching solution composition of the present invention is one in which the ratio (aspect ratio) of the height (depth) to the diameter of the hole (7) of the unit cell (1) is particularly high (high aspect ratio), and the height of the hole (7) is 2.5 to 10 μm, the diameter is 100 to 200 nm, and the height / diameter (aspect ratio) of the hole (7) is 12.5 to 100.

[0035] When an etching target having such a high aspect ratio is immersed in the etching solution composition, the etching solution composition penetrates through the opening of the hole (7) of the unit cell (1) toward the Si substrate (2) and then reaches the Si substrate (2). Therefore, the gate thin film (3) closer to the opening of the hole (7) comes into contact with the etching solution composition earlier than the gate thin film (3) closer to the Si substrate (2). Due to this time lag, when the etching rate is calculated from the immersion time and the etching amount, the etching rate tends to vary depending on the position of the gate thin film (3).

[0036] In contrast, the etching rate of the etching solution composition of the present invention is suppressed, and therefore, even when used on an etching target having a high aspect ratio, etching proceeds without causing the above-mentioned unevenness in the etching rate. For example, if the pair of gate thin film (3) and insulating film (4) in the unit cell (1) is divided into three equal parts, an upper layer (11), a middle layer (12), and a lower layer (13) in order of proximity to the opening of the hole (7), the closer the ratio of the average recess depth at multiple locations in the upper layer (11) to the average recess depth at multiple locations in the lower layer (13) (hereinafter also referred to as the "upper layer / lower layer ratio") is to 1, the more uniformly the gate thin film (3) is etched throughout the entire unit cell (1). The upper layer / lower layer ratio is preferably 1.5 or less, more preferably 1.0 to 1.2, and even more preferably 1.0.

[0037] The method for producing the etching solution composition of the present invention is not particularly limited as long as the etching solution composition is an etching solution composition that contains (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a halogen compound, and (E) water.

[0038] The preferred embodiments of the components (A) to (E), the component (F) that may be further contained, and the optional components in the method for producing the etching liquid composition of the present invention are as described above.

[0039] The present invention also relates to an etching method using the above-mentioned etching solution composition. The temperature (liquid temperature) of the etching solution composition during etching is 15 to 50°C, preferably 15 to 35°C, and more preferably 20 to 30°C. If the temperature of the etching solution composition of the present invention during etching exceeds 50° C., it may become impossible to suppress the etching rate. In particular, when an etching target has a high aspect ratio, the upper layer / lower layer ratio becomes large, which may make it difficult to form a precise three-dimensional structure. In the etching method using the etching solution composition of the present invention, preferred embodiments of the components (A) to (E), the component (F) that may be further contained, and any optional components, as well as preferred embodiments of the metal to be etched, are as described above.

[0040] The present invention has been described in detail above based on preferred embodiments, but the present invention is not limited to these, and each component can be replaced with any component that can perform a similar function, or any component can be added. [Example]

[0041] The present invention will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples.

[0042] The etching solution compositions were prepared and evaluated as follows.

[0043] [Preparation of Etching Solution Composition] Etching solution compositions were prepared at the concentrations shown in the table below. The following components were used: Nitric acid: manufactured by Kanto Chemical Co., Ltd. Acetic acid: manufactured by Kanto Chemical Co., Ltd. Nitrilotris(methylenephosphonic acid): manufactured by Cherest Co., Ltd. HCl: manufactured by Kanto Chemical Co., Ltd. NH4Cl: manufactured by Kanto Chemical Co., Ltd. KCl: manufactured by Kanto Chemical Co., Ltd. NaCl: manufactured by Kanto Chemical Co., Ltd. 1-Hydroxyethane-1,1-diphosphonic acid: Tokyo Chemical Industry Co., Ltd. Water: Ultrapure water purified by an ultrapure water system manufactured by Merck Ltd. H3PO4: Kanto Chemical Co., Ltd. PBTC (2-phosphonobutane-1,2,4-tricarboxylic acid): manufactured by Cherest Co., Ltd.

[0044] [Test board] A 15x15mm substrate was used as the test substrate, on which a plurality of unit cells were formed, each of which was made up of a gate thin film containing molybdenum and an insulating film made of SiO2 laminated alternately.

[0045] [Etching of test substrate] A test substrate was immersed in 100 mL of the etching solution composition of each Example and Comparative Example. The immersion was carried out for 10 to 120 minutes under stirring at approximately 200 rpm. Unless otherwise specified in the table below, the liquid temperature of the etching solution composition was maintained at 25°C while the test substrate was immersed. The test substrate was then removed from the etching solution composition, washed with deionized water, and dried by blowing nitrogen gas to obtain an etched test substrate.

[0046] [Evaluation of etching rate and upper / lower layer ratio] The etched test substrate was cut in the center, and the cross section was observed using a field emission scanning electron microscope (FE-SEM: SU8220, Hitachi High-Tech Fielding Corporation) to measure the etched depth of the gate thin film (recess depth: the length etched in the direction parallel to the Si substrate). The measurement details are described below with reference to Figure 2, which shows (i) a schematic diagram of the etched test substrate and (ii) an enlarged schematic diagram of the pair of gate thin film and insulating film after etching. The pair of gate thin film (3) and insulating film (4) of the unit cell (1) in the etched test substrate was divided into three equal parts, an upper layer (11), a middle layer (12), and a lower layer (13), in order of proximity to the opening of the hole (7), and the recess depth (d) of the gate thin film (3) was measured. Specifically, the recess depth (d) of the gate thin film (3) was measured at 15 to 20 locations on each side of the upper layer (11), middle layer (12), and lower layer (13) of one unit cell, and the average value of each was taken as the average recess depth of the upper layer (11), middle layer (12), and lower layer (13). The etching rate [nm / min.] was calculated as the slope of a straight line derived from the relationship between the average recess depth of each of the upper layer (11), middle layer (12) and lower layer (13) and the immersion time of the test substrate. Moreover, the upper layer / lower layer ratio was calculated by dividing the average recess amount of the upper layer (11) by the average recess amount of the lower layer (13).

[0047] [Evaluation of etched surface shape] The surface of the gate thin film of the test substrate after the etching treatment and cleavage as described above was observed using image analysis software (ImageJ), and the shape was evaluated as follows. Good (good): A smooth gate thin film surface was observed. Δ (slightly bad): A slightly rough gate thin film surface was observed. × (bad): A rough gate thin film surface was observed.

[0048] [Examples 1 to 4] The etching liquid compositions of Examples 1 to 4 were prepared at the concentrations shown in the table below, and test substrates were etched using the compositions.

[0049] [Table 1]

[0050] The etching solution compositions of Examples 1 to 4 were able to etch the upper, middle, and lower layers of the test substrate using a gate thin film containing molybdenum with approximately uniform recess depths, and the shape of the gate thin film surface after etching was also good.

[0051] [Examples 5 to 8] (F) Etching solution compositions of Examples 5 to 8 further containing 1-hydroxyethane-1,1-diphosphonic acid (HEDP) were prepared at the concentrations shown in the table below, and test substrates were etched using these compositions.

[0052] [Table 2]

[0053] The etching solution compositions of Examples 5 to 8 were able to etch the upper, middle, and lower layers of the test substrate using a gate thin film containing molybdenum with approximately uniform recess depths, and the shape of the gate thin film surface after etching was also good.

[0054] [Comparative Examples 1 to 3] Etching liquid compositions of Comparative Examples 1 to 3 were prepared at the concentrations shown in the table below, and test substrates were etched using the compositions.

[0055] [Table 3]

[0056] It was found from Comparative Examples 1 to 3 that the etching solution compositions containing nitric acid, acetic acid, NTMP, and water but not containing a halogen compound exhibited insufficient suppression of the etching rate and / or an etched surface shape of Δ (slightly poor) compared to Examples 1 to 8, and that the desired etching performance could not be achieved even by reducing the nitric acid concentration. This indicates that the halogen compound is important for obtaining the desired etching performance.

[0057] [Comparative Examples 4 to 6] The etching liquid compositions of Comparative Examples 4 to 6 were prepared at the concentrations shown in the table below, and test substrates were etched using the compositions.

[0058] [Table 4] It was found from Comparative Examples 4 to 6 that the etching solution compositions containing nitric acid, acetic acid, NH4Cl as a halogen compound, and water but not NTMP exhibited insufficient suppression of the etching rate and / or the etched surface shape was poor compared to Examples 1 to 8. This indicates that NTMP is important for obtaining the desired etching performance. [Industrial Applicability]

[0059] The use of the etching solution composition of the present invention makes it possible to provide a good etched surface profile at a controlled etching rate for the metal to be etched. The etching solution composition of the present invention is particularly suitable for use in the manufacture of a 3D NAND flash memory in which multiple gate thin films containing molybdenum and insulating films are alternately stacked. [Explanation of symbols]

[0060] 1 unit cell 2. Si substrate 3 Gate thin film 4. Insulating film 5 Poly-Si channel 6. Insulating film 7 holes 11 Upper layer 12 Middle layer 13 Lower layer d Recess amount

Claims

1. An etching solution composition for molybdenum or a metal containing molybdenum for producing a pattern having a three-dimensional structure, comprising: An etching solution composition comprising: (A) nitric acid, (B) acetic acid, (C) nitrilotris(methylenephosphonic acid), (D) a chloride, and (E) water.

2. 10. The etchant composition of claim 1, wherein the concentration of (D) chloride is greater than 0.05 M based on the etchant composition.

3. 3. The etching solution composition according to claim 1, further comprising (F) 1-hydroxyethane-1,1-diphosphonic acid.

4. The etching solution composition according to any one of claims 1 to 3, wherein the etching solution composition does not contain a peroxide.

5. A method for forming a recess, the method comprising treating with the etchant composition of any one of claims 1 to 4.

6. An etching method using the etching solution composition according to any one of claims 1 to 4, wherein the temperature of the etching solution composition is 15°C to 50°C.

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