Wet etching formulations and related methods

Abstract

Wet etching compositions and related methods are provided herein. The wet etching composition for molybdenum may include phosphoric acid, acetic acid, nitric acid, and an additive to reduce the oxidation rate of the MoOx layer. The additive may be present in an amount of 0.01 wt% to 5 wt% based on the total weight of the wet etching composition.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of wet etch formulations and related methods. BACKGROUND

[0002] 3D NAND structures include molybdenum layers that must be selectively removed by etching. Removing molybdenum in the recesses of the 3D NAND structure without removing non-molybdenum materials, such as tetraethyl orthosilicate (TEOS) and aluminum oxide, remains a continuing challenge. Another continuing challenge is the lack of uniformity in etch depth, resulting in different depths of etched molybdenum layers. SUMMARY

[0003] Some embodiments relate to a wet etch composition for molybdenum materials. In some embodiments, the wet etch composition includes at least one of phosphoric acid, acetic acid, nitric acid, an additive to reduce the oxidation rate of the MoO2layer, or any combination thereof. In some embodiments, the additive is present in an amount of 0.01 wt% to 5 wt% based on the total weight of the wet etch composition. x

[0004] Some embodiments relate to a method for etching molybdenum materials. In some embodiments, the method includes one or more of the following steps: obtaining a structure including a plurality of recesses and molybdenum material disposed in the plurality of recesses; and contacting the structure with a wet etch composition to remove at least a portion of the molybdenum material. In some embodiments, the wet etch composition includes at least one of phosphoric acid, acetic acid, nitric acid, an additive to reduce the oxidation rate of the MoO2layer, or any combination thereof. In some embodiments, the additive is present in an amount of 0.01 wt% to 5 wt% based on the total weight of the wet etch composition. x BRIEF DESCRIPTION OF DRAWINGS

[0005] Some embodiments of the present disclosure are described herein, with reference to the attached drawings. The drawings are for purposes of illustrating the embodiments of the present disclosure and are not intended to limit the present disclosure. The drawings in which like reference numerals refer to identical or corresponding elements are now described.

[0006] Figure 1 A diagram is presented showing a process flow of a 3D NAND structure with tetraethyl orthosilicate (TEOS), aluminum oxide, and molybdenum, in accordance with some embodiments.

[0007] Figure 2 A diagram is presented showing results of a method for removing molybdenum, in accordance with some embodiments, in which a 3D NAND structure with molybdenum is subjected to a wet etch composition.

[0008] ​​ Figure 3 A flow diagram of a method for removing molybdenum according to some embodiments is presented, wherein a 3D NAND structure having molybdenum is subjected to a wet etch composition. DETAILED DESCRIPTION

[0009] Among the benefits and improvements that have been disclosed, other objects and advantages of this application will become apparent from the following description, taken in conjunction with the accompanying drawings. Detailed embodiments of the application are discussed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the application. Moreover, each example given herein is intended to be one illustration amongst alternative examples given. For example, the various embodiments described herein can be used in combination with one another.

[0010] Any prior patents and publications referred to herein are incorporated by reference in their entirety.

[0011] Throughout this specification and claims, the following terms have the meanings indicated, unless the context clearly indicates otherwise. The phrases “in one embodiment,” “in an embodiment,” and “in some embodiments” as used herein do not necessarily refer to the same embodiment, although they may. Also, the phrases “in another embodiment” and “in some other embodiments” as used herein do not necessarily refer to different embodiments, although they may. All embodiments of the application are intended to be combinable with each other, unless the context clearly indicates otherwise.

[0012] As used herein, unless the context clearly indicates otherwise, the term “based on” is not exclusive and allows for the inclusion of other factors. Also throughout this specification, the meaning of “a,” “an,” and “the” include plural references. The meaning of “in” includes “in” and “on.”

[0013] Some embodiments relate to wet etch formulations and related methods for selectively removing molybdenum material from microelectronic devices such as, for example but not limited to, 3D NAND structures. Selective removal of molybdenum can improve recess depth uniformity across the 3D NAND structure to maintain yield and prevent variations in chemical composition and electrical performance. In some embodiments, a wet etch composition can include phosphoric acid (H3PO4), acetic acid (CH3COOH), nitric acid (HNO3), and an additive to reduce the oxidation rate of a molybdenum oxide (MoO x ) layer. In some embodiments, the additive can be present in an amount of 0.01 wt% to 5 wt% based on the total weight of the wet etch composition. In some embodiments, x of the MoO x (oxidized molybdenum) layer is 1 to 5.

[0014] The additive to the wet etching composition may be at least one of a nitrogen-containing salt, a nitrogen-containing acid, a nitrogen-containing compound, a phosphorus-containing acid, a phosphorus-containing oxide, and a phosphorus-containing salt, or any combination thereof. In some embodiments, the wet etching composition may be at least one of an ammonium salt, an organic chloride salt, a phosphonic acid, a phosphine oxide, an ammonium salt of phosphoric acid, a benzotriazole, and citric acid, a quaternary ammonium salt, or any combination thereof. In some embodiments, the quaternary ammonium salt comprises a nitrogen-containing salt having four (4) bonds. In some embodiments, the additive may be at least one of benzyldimethyldodecylammonium chloride, 1-dodecylpyridinium chloride, 1-methyl-3-N-octylimidazolium chloride, 1-methyl-3-N-octylimidazolium chloride, and 1-decyl-3-methylimidazolium chloride, or any combination thereof. In some embodiments, the additive may be at least one of n-dodecylphosphonic acid and benzylphosphonic acid, or any combination thereof. In some embodiments, the additive may be at least one of trioctylphosphine oxide, triphenylphosphine oxide, triphenylphosphine oxide, triethylamine phosphate, ammonium dihydrogen phosphate, and 5-methyl-1H-benzotriazole, or any combination thereof.

[0015] The wet etching composition may comprise 1% to 20% by weight of phosphoric acid, based on the total weight of the wet etching composition, or any range or sub-range between 1% and 20%. For example, in some embodiments, the weight percentage of phosphoric acid, based on the total weight of the wet etching composition, may be 1% to 15%, 1% to 10%, or 5% to 20%. In some embodiments, the weight percentage of phosphoric acid, based on the total weight of the wet etching composition, may be 2% to 20%, 3% to 20%, 4% to 20%, 5% to 20%, 6% to 20%, 7% to 20%, 8% to 20%, 9% to 20%, 10% to 20%, 11% to 20%, 12% to 20%, 13% to 20%, 14% to 20%, 15% to 20%, 16% to 20%, 17% to 20%, 18% to 20%, or 19% to 20%. In some embodiments, the weight percentage of phosphoric acid based on the total weight of the wet etching composition may be 1% to 19%, 1% to 18%, 1% to 17%, 1% to 16%, 1% to 15%, 1% to 14%, 1% to 13%, 1% to 12%, 1% to 11%, 1% to 10%, 1% to 9%, 1% to 8%, 1% to 7%, 1% to 6%, 1% to 5%, 1% to 4%, 1% to 3%, or 1% to 2%.

[0016] The wet etching composition may comprise 50% to 90% acetic acid by weight, based on the total weight of the wet etching composition, or any range or sub-range between 50% and 90%. For example, in some embodiments, the weight percentage of acetic acid, based on the total weight of the wet etching composition, may be 55% to 90%, 60% to 90%, 65% to 90%, 70% to 90%, 75% to 90%, 80% to 90%, or 85% to 90%. In some embodiments, the weight percentage of acetic acid based on the total weight of the wet etching composition may be 51% to 90%, 52% to 90%, 53% to 90%, 54% to 90%, 55% to 90%, 56% to 90%, 57% to 90%, 58% to 90%, 59% to 90%, 60% to 90%, 61% to 90%, 62% to 90%, 63% to 90%, 64% to 90%, 65% to 90%, 66% to 90%, 67% to 90%, 68% to 90%. , 69% to 90%, 70% to 90%, 71% to 90%, 72% to 90%, 73% to 90%, 74% to 90%, 75% to 90%, 76% to 90%, 77% to 90%, 78% to 90%, 79% to 90%, 80% to 90%, 80% to 95%, 81% to 90%, 82% to 90%, 83% to 90%, 84% to 90%, 85% to 90%, 86% to 90%, 87% to 90%, 88% to 90%, or 89% to 90%. In some embodiments, the weight percentage of acetic acid based on the total weight of the wet etching composition may be 50% to 89%, 50% to 88%, 50% to 87%, 50% to 86%, 50% to 85%, 50% to 84%, 50% to 83%, 50% to 82%, 50% to 81%, 50% to 80%, 50% to 79%, 50% to 78%, 50% to 77%, 50% to 76%, 50% to 75%, 50% to 74%, 50% to 73%, 50% to 74%. to 72%, 50% to 71%, 50% to 70%, 50% to 69%, 50% to 68%, 50% to 67%, 50% to 66%, 50% to 65%, 50% to 64%, 50% to 63%, 50% to 62%, 50% to 61%, 50% to 60%, 50% to 59%, 50% to 58%, 50% to 57%, 50% to 56%, 50% to 55%, 50% to 54%, 50% to 53%, 50% to 52%, or 50% to 51%.

[0017] The wet etch composition can be 0.1 wt% to 20 wt% nitric acid, or any range or sub-range between 0.1% and 20%, based on the total weight of the wet etch composition. For example, in some embodiments, the weight percent of nitric acid based on the total weight of the wet etch composition can be 1% to 20%, 1% to 15%, 1% to 10%, or 5% to 20%. In some embodiments, the weight percent of nitric acid based on the total weight of the wet etch composition can be 1% to 20%, 2% to 20%, 3% to 20%, 4% to 20%, 5% to 20%, 6% to 20%, 7% to 20%, 8% to 20%, 9% to 20%, 10% to 20%, 11% to 20%, 12% to 20%, 13% to 20%, 14% to 20%, 15% to 20%, 16% to 20%, 17% to 20%, 18% to 20%, or 19% to 20%. In some embodiments, the weight percent of nitric acid based on the total weight of the wet etch composition can be 0.1% to 19%, 0.1% to 18%, 0.1% to 17%, 0.1% to 16%, 0.1% to 15%, 0.1% to 14%, 0.1% to 13%, 0.1% to 12%, 0.1% to 11%, 0.1% to 10%, 0.1% to 9%, 0.1% to 8%, 0.1% to 7%, 0.1% to 6%, 0.1% to 5%, 0.1% to 4%, 0.1% to 3%, 0.1% to 2%, or 0.1% to 1%. In some embodiments, the weight percent of nitric acid based on the total weight of the wet etch composition can be 0.1% to 5%, 0.5% to 5%, 1% to 5%, 1.5% to 5%, 2% to 5%, 2.5% to 5%, 3% to 5%, 3.5% to 5%, 4% to 5%, or 4.5% to 5%. In some embodiments, the weight percent of nitric acid based on the total weight of the wet etch composition can be 0.1% to 5%, 0.1% to 4.5%, 0.1% to 4%, 0.1% to 3.5%, 0.1% to 3%, 0.1% to 2.5%, 0.1% to 2%, 0.1% to 1.5%, 0.1% to 1%, or 0.1% to 0.5%.

[0018] The wet etching composition may further comprise 0.1% to 10% by weight of citric acid, based on the total weight of the wet etching composition, or any range or sub-range between 0.1% and 10%. For example, in some embodiments, the weight percentage of citric acid, based on the total weight of the wet etching composition, may be 0.1% to 10%, 1% to 5%, 1% to 2.5%, or 2.5% to 5%. In some embodiments, the weight percentage of citric acid, based on the total weight of the wet etching composition, may be 0.1% to 5%, 0.5% to 5%, 1% to 5%, 1.5% to 5%, 2% to 5%, 2.5% to 5%, 3% to 5%, 3.5% to 5%, 4% to 5%, or 4.5% to 5%. In some embodiments, the weight percentage of citric acid based on the total weight of the wet etching composition may be 0.1% to 5%, 0.1% to 4.5%, 0.1% to 4%, 0.1% to 3.5%, 0.1% to 3%, 0.1% to 2.5%, 0.1% to 2%, 0.1% to 1.5%, 0.1% to 1%, or 0.1% to 0.5%.

[0019] The wet etching composition may not include a tungsten compound. In some embodiments, the tungsten compound includes at least one of tungsten oxide, tungsten trioxide, tungstic acid, sodium tungstate, ammonium paratungstate, tungsten carbide, and ditungsten carbide, or any combination thereof.

[0020] Some embodiments relate to wet etching formulations and related methods for selectively removing molybdenum from 3D NAND structures. In some embodiments, a method may include obtaining a structure comprising a plurality of recesses and a molybdenum material disposed in the plurality of recesses and contacting the structure with a wet etching composition to remove at least a portion of the molybdenum material. In some embodiments, the structure may have a plurality of recesses and a molybdenum material disposed in the plurality of recesses. In some embodiments, the wet etching composition may include phosphoric acid, acetic acid, nitric acid, and a catalyst for reducing MoO x In some embodiments, the additive may be present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition. In some embodiments, the MoO x The x of the (molybdenum oxide) layer is 1 to 5.

[0021] Figure 1 A diagram is presented showing a process flow 100 for a 3D NAND structure having tetraethyl orthosilicate (TEOS) 102, aluminum oxide 112, and molybdenum 104. The first step in removing the molybdenum 104 may be oxidation 106 of the molybdenum 104 to produce a molybdenum oxide layer 108. After oxidation 106, the molybdenum oxide layer 108 may undergo etching 110. After etching 110, the recessed portion of the 3D NAND structure may be uniform.

[0022] Figure 2 A diagram of the results 200 of a method for removing molybdenum 104 is presented. Figures 1 to 3 As shown in FIG, a 3D NAND structure having molybdenum 104 is subjected to a wet etching composition 210. In some embodiments, the wet etching composition 210 is a PAN composition (phosphoric acid, acetic acid, and nitric acid). In some embodiments, the PAN composition may include an additive for reducing the oxidation rate of the molybdenum oxide layer 108. In some embodiments, the additive may be present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition 210.

[0023] Figure 3 A flow chart of a method 300 for removing molybdenum is presented. Figures 1 to 3 As shown in FIG, a 3D NAND structure having molybdenum 104 is subjected to a wet etching composition 210. In some embodiments, method 300 may comprise obtaining a structure comprising a plurality of recesses and a molybdenum material disposed in the plurality of recesses 310 and contacting the structure with a wet etching composition to remove at least a portion of the molybdenum material 320. In some embodiments, the structure may be a 3D NAND structure. In some embodiments, the wet etching composition 210 may comprise phosphoric acid, acetic acid, nitric acid, and an additive for reducing the oxidation rate of the molybdenum oxide layer. In some embodiments, the additive may be present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition.

[0024] Example 1

[0025] Various wet etching compositions were prepared and the performance of each was compared to a control composition.All samples were prepared in the following order of addition: nitric acid, glacial acetic acid, phosphoric acid, water, and additives.

[0026] Sample A is a wet etching composition comprising 1 to 15 wt% phosphoric acid, 80 to 95 wt% acetic acid, 0.1 to 5 wt% nitric acid, 1 to 10 wt% water, and 1 wt% benzyldimethyldodecyl ammonium chloride. Sample B is a wet etching composition comprising 1 to 15 wt% phosphoric acid, 80 to 95 wt% acetic acid, 0.1 to 5 wt% nitric acid, 1 to 10 wt% water, and 0.05 wt% 1-dodecylpyridinium chloride. Sample C is a wet etching composition comprising 1 to 15 wt% phosphoric acid, 80 to 95 wt% acetic acid, 0.1 to 5 wt% nitric acid, 1 to 10 wt% water, and 0.05 wt% 1-methyl-3-N-octylimidazolium chloride. Sample D is a wet etching composition including 1 wt % to 15 wt % of phosphoric acid, 80 wt % to 95 wt % of acetic acid, 0.1 wt % to 5 wt % of nitric acid, 1 wt % to 10 wt % of water, 0.01 wt % to 5 wt % of 1-dodecylpyridinium chloride, and 0.01 wt % to 5 wt % of citric acid.

[0027] The control composition comprises 1 to 15 weight percent phosphoric acid, 80 to 95 weight percent acetic acid, 0.1 to 5 weight percent nitric acid, 1 to 10 weight percent water, and no additives. Unless otherwise provided herein, all weight percentages are based on the total weight of the composition.

[0028] Each of the compositions was applied to a structure comprising a plurality of recesses and a platinum material disposed in the plurality of recesses at room temperature for a contact period. After the contact period, the average depth of the platinum material in the top, middle, and bottom of the structure was measured and reported in Table 1 below.

[0029] Table 1: Wet Etching Composition Properties

[0030] formulations Process conditions Improvement in concave uniformity (%) comparison RT / 3.5min - Sample A RT / 6min 87.9 Sample B RT / 3.5min 90.9 Sample C RT / 3.5min 84.8

[0031] As shown, adding a small amount of the additive to each of the wet etching compositions significantly improved the average recess depth variance (ie, improved recess depth uniformity) of the molybdenum material relative to the control composition.

[0032] aspect

[0033] Various aspects are described below. It should be understood that any one or more of the features listed in the following aspects may be combined with any one or more other aspects.

[0034] Aspect 1. A wet etching composition for molybdenum, comprising:

[0035] Phosphoric acid;

[0036] acetic acid;

[0037] nitric acid; and

[0038] To reduce MoO x The oxidation rate of the additive layer,

[0039] The additive is present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition.

[0040] Aspect 2. The wet etching composition according to aspect 1, wherein the additive comprises at least one of an ammonium salt, an organic chloride salt, a phosphonic acid, a phosphine oxide, an ammonium salt of phosphoric acid, benzotriazole, and citric acid, or any combination thereof.

[0041] Aspect 3. The wet etching composition according to any one of aspects 1 to 2, wherein the additive comprises at least one of benzyldimethyldodecylammonium chloride, 1-dodecylpyridinium chloride, 1-methyl-3-N-octylimidazolium chloride, 1-methyl-3-N-octylimidazolium chloride, and 1-decyl-3-methylimidazolium chloride, or any combination thereof.

[0042] Aspect 4. The wet etching composition according to any one of aspects 1 to 3, wherein the additive comprises at least one of n-dodecylphosphonic acid and benzylphosphonic acid, or any combination thereof.

[0043] Aspect 5. The wet etching composition according to any one of aspects 1 to 4, wherein the additive comprises at least one of trioctylphosphine oxide, triphenylphosphine oxide, triphenylphosphine oxide, triethylamine phosphate, ammonium dihydrogen phosphate, and 5-methyl-1H-benzotriazole, or any combination thereof.

[0044] Aspect 6. The wet etching composition according to any one of aspects 1 to 5, wherein the wet etching composition comprises 1 wt % to 20 wt % of phosphoric acid based on the total weight of the wet etching composition.

[0045] Aspect 7. The wet etching composition according to any one of aspects 1 to 6, wherein the wet etching composition comprises 50 wt% to 90 wt% of acetic acid based on the total weight of the wet etching composition.

[0046] Aspect 8. The wet etching composition according to any one of aspects 1 to 7, wherein the wet etching composition comprises 0.1 wt % to 20 wt % of nitric acid based on the total weight of the wet etching composition.

[0047] Aspect 9. The wet etching composition according to any one of aspects 1 to 8, wherein the wet etching composition does not contain a tungsten compound.

[0048] Aspect 10. The wet etching composition according to any one of aspects 1 to 9, wherein the MoO x The x of the layer is 1 to 5.

[0049] Aspect 11. A method comprising:

[0050] obtaining a structure comprising a plurality of recesses and a molybdenum material disposed in the plurality of recesses; and

[0051] contacting the structure with a wet etching composition to remove at least a portion of the molybdenum material,

[0052] wherein the wet etching composition comprises:

[0053] Phosphoric acid;

[0054] acetic acid;

[0055] nitric acid; and

[0056] To reduce MoO x The oxidation rate of the additive layer,

[0057] The additive is present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition.

[0058] Aspect 12. The method according to aspect 11, wherein the additive comprises at least one of an ammonium salt, an organic chloride salt, a phosphonic acid, a phosphine oxide, an ammonium salt of phosphoric acid, a benzotriazole, and citric acid, or any combination thereof.

[0059] Aspect 13. The method according to any one of aspects 11 to 12, wherein the additive comprises at least one of benzyldimethyldodecylammonium chloride, 1-dodecylpyridinium chloride, 1-methyl-3-N-octylimidazolium chloride, 1-methyl-3-N-octylimidazolium chloride, and 1-decyl-3-methylimidazolium chloride, or any combination thereof.

[0060] Aspect 14. The method according to any one of aspects 11 to 13, wherein the additive comprises at least one of n-dodecylphosphonic acid and benzylphosphonic acid, or any combination thereof.

[0061] Aspect 15. The method according to any one of aspects 11 to 14, wherein the additive comprises at least one of trioctylphosphine oxide, triphenylphosphine oxide, triphenylphosphine oxide, triethylamine phosphate, ammonium dihydrogen phosphate, and 5-methyl-1H-benzotriazole, or any combination thereof.

[0062] Aspect 16. The method of any one of aspects 11 to 15, wherein the wet etching composition comprises 1 wt % to 20 wt % phosphoric acid based on the total weight of the wet etching composition.

[0063] Aspect 17. The method according to any one of aspects 11 to 16, wherein the wet etching composition comprises 50 wt% to 90 wt% of acetic acid based on the total weight of the wet etching composition.

[0064] Aspect 18. The method of any one of aspects 11 to 17, wherein the wet etching composition comprises 0.1 wt % to 20 wt % nitric acid based on the total weight of the wet etching composition.

[0065] Aspect 19. The method of any one of aspects 11 to 18, wherein the wet etching composition does not contain a tungsten compound.

[0066] Aspect 20. The method according to any one of aspects 11 to 19, wherein the MoO x The x of the layer is 1 to 5.

[0067] It should be understood that changes may be made in details, especially in matters of construction materials employed and the shape, size, and arrangement of parts without departing from the scope of the invention. The specification and described embodiments are examples, with the true scope and spirit of the invention being indicated by the following claims.

Claims

1. A wet etching composition for molybdenum, comprising: Phosphoric acid; acetic acid; nitric acid; and To reduce MoO x The oxidation rate of the additive layer, The additive is present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition.

2. The wet etching composition of claim 1, wherein the additive comprises at least one of an ammonium salt, an organic chloride salt, a phosphonic acid, a phosphine oxide, an ammonium salt of phosphoric acid, a benzotriazole, and citric acid, or any combination thereof.

3. The wet etching composition according to claim 1, wherein the additive comprises at least one of benzyldimethyldodecylammonium chloride, 1-dodecylpyridinium chloride, 1-methyl-3-N-octylimidazolium chloride, 1-methyl-3-N-octylimidazolium chloride, and 1-decyl-3-methylimidazolium chloride, or any combination thereof. 4 . The wet etching composition of claim 1 , wherein the additive comprises at least one of n-dodecylphosphonic acid and benzylphosphonic acid, or any combination thereof. 5 . The wet etching composition according to claim 1 , wherein the additive comprises at least one of trioctylphosphine oxide, triphenylphosphine oxide, triphenylphosphine oxide, triethylammonium phosphate, ammonium dihydrogen phosphate, and 5-methyl-1H-benzotriazole, or any combination thereof. 6 . The wet etching composition of claim 1 , wherein the wet etching composition comprises 1 wt % to 20 wt % of phosphoric acid based on the total weight of the wet etching composition.

7. The wet etching composition of claim 1, wherein the wet etching composition comprises 50 wt% to 90 wt% of acetic acid based on the total weight of the wet etching composition. 8 . The wet etching composition of claim 1 , wherein the wet etching composition comprises 0.1 wt % to 20 wt % nitric acid based on the total weight of the wet etching composition. 9 . The wet etching composition of claim 1 , wherein the wet etching composition does not contain a tungsten compound.

10. The wet etching composition according to claim 1, wherein the MoO x The x of the layer is 1 to 5.

11. A method comprising: obtaining a structure comprising a plurality of recesses and a molybdenum material disposed in the plurality of recesses; and contacting the structure with a wet etching composition to remove at least a portion of the molybdenum material, wherein the wet etching composition comprises: Phosphoric acid; acetic acid; nitric acid; and To reduce MoO x The oxidation rate of the additive layer, The additive is present in an amount of 0.01 wt % to 5 wt % based on the total weight of the wet etching composition.

12. The method of claim 11, wherein the additive comprises at least one of an ammonium salt, an organic chloride salt, a phosphonic acid, a phosphine oxide, an ammonium salt of phosphoric acid, a benzotriazole, and citric acid, or any combination thereof.

13. The method of claim 11, wherein the additive comprises at least one of benzyldimethyldodecylammonium chloride, 1-dodecylpyridinium chloride, 1-methyl-3-N-octylimidazolium chloride, 1-methyl-3-N-octylimidazolium chloride, and 1-decyl-3-methylimidazolium chloride, or any combination thereof.

14. The method of claim 11, wherein the additive comprises at least one of n-dodecylphosphonic acid and benzylphosphonic acid, or any combination thereof.

15. The method of claim 11, wherein the additive comprises at least one of trioctylphosphine oxide, triphenylphosphine oxide, triphenylphosphine oxide, triethylammonium phosphate, ammonium dihydrogen phosphate, and 5-methyl-1H-benzotriazole, or any combination thereof.

16. The method of claim 11, wherein the wet etching composition comprises 1 wt% to 20 wt% of phosphoric acid based on the total weight of the wet etching composition.

17. The method of claim 11, wherein the wet etching composition comprises 50 wt% to 90 wt% acetic acid based on the total weight of the wet etching composition.

18. The method of claim 11, wherein the wet etching composition comprises 0.1 wt% to 20 wt% nitric acid based on the total weight of the wet etching composition.

19. The method of claim 11, wherein the wet etching composition does not contain a tungsten compound.

20. The method according to claim 11, wherein the MoO x The x of the layer is 1 to 5.

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