Compositions and methods for selectively etching silicon nitride

Abstract

This invention discloses compositions and methods for selectively etching silicon nitride from polysilicon, silicon oxide materials, and / or silicide materials from microelectronic devices.

Description

[Technical Field]

[0001] This disclosure relates to the art of compositions and methods for selectively etching silicon nitride.

[0002] Cross-reference of related applications This disclosure claims priority and interest in U.S. Provisional Patent Application No. 63 / 452362, filed on 15 March 2023. [Background technology]

[0003] Self-aligned polysilicon gate structures contain a layer of silicon nitride that must be selectively removed. Removing silicon nitride from other gate structure materials such as polysilicon, silicon oxide, and metal silicates remains an ongoing challenge. Another ongoing challenge is the large amount of foam produced during silicon nitride etching and silicon regrowth. [Overview of the project]

[0004] Some embodiments of this disclosure use phosphoric acid, water, and the following formula: TIFF2026509373000002.tif35170[In the formula, R 1 , R 2 and R 3 Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide; n is at least 1; Q is, TIFF2026509373000003.tif42170 or TIFF2026509373000004.tif32170[In the formula, R a and R b Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl; R c [The alkylsilane compound is hydrogen, alkyl, cycloalkyl, aryl, or alkaryl] Relates to a composition containing

[0005] In some embodiments, R 1 , R 2 and R 3 are each methoxy.

[0006] In some embodiments, R a and R b are hydrogen.

[0007] In some embodiments, R a is hydrogen and R b is alkyl.

[0008] In some embodiments, n is from 1 to 6.

[0009] In some embodiments, the alkylsilane compound has the following formula: TIFF2026509373000005.tif48170 or TIFF2026509373000006.tif42170 or TIFF2026509373000007.tif50170 or TIFF2026509373000′008.tif50170 or TIFF2026509373000009.tif49170 [wherein, R 4 , R 5 and R 6 are independently compounds of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, and their isomers].

[0010] [[ID=j57]]In some embodiments, the composition contains 75 wt% to 90 wt% phosphoric acid based on the total weight of the composition.

[0011] In some embodiments, the composition contains 10 wt% to 20 wt% water based on the total weight of the composition.

[0012] In some embodiments, the composition contains 0.01% to 5% by weight of an alkylsilane compound based on the total weight of the composition.

[0013] In some embodiments, when the composition is mixed at 25°C to 160°C at 200 RPM, it produces less foam than a composition that does not contain alkylsilane compounds.

[0014] Some embodiments relate to methods for obtaining a structure comprising silicon nitride and silicon oxide, and for removing at least a portion of the silicon nitride by contacting this structure with a composition.

[0015] In some embodiments, the composition includes phosphoric acid, water, and the following formula: TIFF2026509373000010.tif35170[In the formula, R 1 , R 2 and R 3 Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide, n is at least 1, and Q is TIFF2026509373000011.tif42170 or TIFF2026509373000012.tif32170[In the formula, R a and R b Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl, and R c [The alkylsilane compound is hydrogen, alkyl, cycloalkyl, aryl, or alkaryl] Includes.

[0016] In some embodiments, R 1 , R 2 and R 3 These are methoxy compounds, respectively.

[0017] In some embodiments, R a and Rb It is hydrogen.

[0018] In some embodiments, R a is hydrogen, and R b It is an alkyl group.

[0019] In some embodiments, n is 1 to 6.

[0020] In some embodiments, the alkylsilane compound is given by the following formula: TIFF2026509373000013.tif48170 or TIFF2026509373000014.tif42170 or TIFF2026509373000015.tif50170 or TIFF2026509373000016.tif50170 or TIFF2026509373000017.tif49170[In the formula, R 4 , R 5 and R 6 These are compounds of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, and their isomers.

[0021] In some embodiments, the composition contains 75% to 90% by weight of phosphoric acid based on the total weight of the composition.

[0022] In some embodiments, the composition contains at least 10% to 20% by weight of water based on the total weight of the composition.

[0023] In some embodiments, the composition contains at least 0.01% to 5% by weight of an alkylsilane compound based on the total weight of the composition.

[0024] In some embodiments, the composition removes a larger proportion of silicon nitride than silicon oxide.

[0025] Some embodiments of this disclosure are described herein, merely as examples, with reference to the accompanying drawings. Further detailed and specific reference to the drawings emphasizes that the illustrated embodiments are illustrative and intended for illustrative purposes of the embodiments of this disclosure. In this regard, the descriptions in conjunction with the drawings will make it clear to those skilled in the art how embodiments of this disclosure may be carried out. [Brief explanation of the drawing]

[0026] [Figure 1] This is a flowchart of a method for selectively etching silicon nitride according to several embodiments. [Figure 2] Figure 1 illustrates the results of the method according to several embodiments. [Modes for carrying out the invention]

[0027] Among these disclosed benefits and improvements, other objectives and advantages of this disclosure will become apparent from the following description in conjunction with the accompanying drawings. While detailed embodiments of this disclosure are disclosed herein, it will be understood that the disclosed embodiments are merely illustrative examples of the various forms in which this disclosure may be embodied. Furthermore, each example shown with respect to the various embodiments of this disclosure is intended to be illustrative, not limiting.

[0028] Prior patents and publications referenced herein are incorporated in their entirety by reference.

[0029] Throughout this specification and the claims, the following terms have the meanings expressly associated herein unless the context clearly indicates otherwise. The phrases “in one embodiment,” “in an embodiment,” and “in some embodiments” as used herein may, but not necessarily, refer to the same embodiment. Furthermore, the phrases “in another embodiment” and “in some other embodiments” as used herein may, but not necessarily, refer to different embodiments. All embodiments of this disclosure are intended to be combinatorial without departing from the scope or spirit of this disclosure.

[0030] When used herein, the term “based on” is not exclusive and, unless explicitly indicated otherwise in the context, may be based on additional factors not listed. Furthermore, throughout this specification, the meanings of “a,” “an,” and “the” include multiple references. The meaning of “in” includes “in” and “on.”

[0031] As used herein, the term “alkyl” refers to a hydrocarbon compound having 1 to 30 carbon atoms. An alkyl having n carbon atoms is called “C n It is sometimes written as "alkyl". For example, "C3 alkyl" may include n-propyl and isopropyl. Alkyls having a range of carbon atoms, such as 1 to 30 carbon atoms, are C1 to C 30 It may be specified as an alkyl group. In some embodiments, the alkyl group is linear. In some embodiments, the alkyl group is branched. In some embodiments, the alkyl group is substituted. In some embodiments, the alkyl group is unsubstituted. In some embodiments, the alkyl group is C1-C 10 Alkyl, C1-C9 alkyl, C1-C8 alkyl, C1-C7 alkyl, C1-C6 alkyl, C1-C5 alkyl, C1-C4 alkyl, C1-C3 alkyl, C2-C 10Alkyl, C3~C 10 Alkyl, C4~C 10 Alkyl, C5~C 10 Alkyl, C6~C 10 Alkyl, C7~C 10 Alkyl, C8~C 10 The alkyl group comprises or is selected from the group consisting of at least one of alkyl, C2-C9 alkyl, C2-C8 alkyl, C2-C7 alkyl, C2-C6 alkyl, C2-C5 alkyl, C3-C5 alkyl, or any combination thereof. In some embodiments, the alkyl group comprises or is selected from the group consisting of at least one of methyl, ethyl, n-propyl, 1-methylethyl (isopropyl), n-butyl, isobutyl, sec-butyl, n-pentyl, 1,1-dimethylethyl (t-butyl), n-pentyl, isopentyl, n-hexyl, isohexyl, 3-methylhexyl, 2-methylhexyl, heptyl, octyl, nonyl, decyl, dodecyl, octadecyl, or any combination thereof.

[0032] As used herein, the term “alkyl” refers to a hydrocarbon chain radical having 1 to 30 carbon atoms. Alkyls can be linked via single bonds. An alkyl having n carbon atoms is called “C n It is sometimes written as "alkyl". For example, "C3 alkyl" may include n-propyl and isopropyl. Alkyls having a range of carbon atoms, such as 1 to 30 carbon atoms, are C1 to C 30 It may be specified as an alkyl group. In some embodiments, the alkyl group is saturated (e.g., single bond). In some embodiments, the alkyl group is unsaturated (e.g., double and / or triple bond). In some embodiments, the alkyl group is linear. In some embodiments, the alkyl group is branched. In some embodiments, the alkyl group is substituted. In some embodiments, the alkyl group is unsubstituted. In some embodiments, the alkyl group is C1-C 12 Alkyl, C1-C 11 Alkyl, C1-C 10The alkyl group may consist of, be composed of, essentially consist of, or be selected from the group comprising alkyl, C1-C9 alkyl, C1-C8 alkyl, C1-C7 alkyl, C1-C6 alkyl, C1-C4 alkyl, C1-C3 alkyl, or any combination thereof. In some embodiments, the alkyl group may consist of, be composed of, essentially consist of, or be selected from the group comprising them.

[0033] As used herein, the term “alkoxy” refers to a radical of the formula -OR (wherein R is an alkyl as defined herein). In some embodiments, the alkoxy may comprise, consist of, essentially consist of, or be selected from the group comprising methoxy, ethoxy, n-propoxy, 1-methylethoxy (isopropoxy), n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy, or any combination thereof.

[0034] As used herein, the term "halogenate" refers to -Cl, -Br, -I, or -F.

[0035] As used herein, the term “cycloalkyl” refers to a non-aromatic carbocyclic group having 3 to 8 carbon atoms in the ring, linked by a single bond. This term includes monocyclic non-aromatic carbocyclic rings and polycyclic non-aromatic carbocyclic rings. For example, to obtain a polycyclic non-aromatic carbocyclic ring, two or more cycloalkyls may be condensed, crosslinked, or condensed and crosslinked. In some embodiments, the cycloalkyl may consist of, essentially consist of, or be selected from the group comprising cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, or any combination thereof.

[0036] As used herein, the term "aryl" refers to an aromatic ring containing carbon and hydrogen atoms. Examples of aryls include, but are not limited to, phenyl, biphenyl, and naphthyl.

[0037] As used herein, "silicon nitride" and "Si3N4" refer to pure silicon nitride (Si3N4), as well as impure silicon nitride containing hydrogen, carbon, and / or oxygen impurities in its crystalline structure.

[0038] As used herein, "silicon oxide" refers to silicon dioxide (SiO₂). x ), for example, SiO2, "thermal oxide" (ThO x This refers to thin films fabricated by methods such as ). Silicon oxide can be deposited on a substrate by any method, for example, by chemical vapor deposition from TEOS or another source, or by thermal deposition. Silicon oxide generally contains commercially available useful low levels of other materials or impurities. Silicon oxide may be present as part of the microelectronic device substrate, for example as an insulating layer, as a mechanism in microelectronic devices.

[0039] As used herein, “remove” corresponds to the removal of at least a portion of the exposed silicon nitrogen layer. For example, partial removal of silicon nitride material includes anisotropic removal of the silicon nitride layer that forms the Si3N4 sidewall by coating / protecting the gate electrode. It is also considered herein that the compositions of the present invention may be used more generally to substantially remove silicon nitride material from a layer of polysilicon and / or silicon oxide. In these circumstances, “substantial removal” is defined as at least 90% in one embodiment, at least 95% in another embodiment, and still in yet another embodiment as at least 99% of the silicon nitride being removed using the compositions of the present invention.

[0040] Some embodiments relate to compositions and methods for the selective removal of silicon nitride from microelectronic devices, which are, for example, without limitation, 3D NAND structures, flat panel displays, microelectromechanical systems (MEMS), integrated circuits, or computer chips. Selective removal of silicon nitride by these compositions can prevent damage to the underlying silicon oxide layer, improve the reliability of semiconductor devices, reduce foaming, and suppress silicon regrowth. In some embodiments, the composition comprises phosphoric acid (H3PO4), water (H2O), and the following formula: TIFF2026509373000018.tif35170[In the formula, R 1 , R 2 and R 3 Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide; n is at least 1; Q is, TIFF2026509373000019.tif42170 or TIFF2026509373000020.tif32170[In the formula, R a and R b Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl; R c [The alkylsilane compound is hydrogen, alkyl, cycloalkyl, aryl, or alkaryl] It may include.

[0041] In some embodiments, R 1 , R 2 and R 3 These are methoxy compounds, respectively.

[0042] In some embodiments, R a and R b It is hydrogen.

[0043] In some embodiments, R a is hydrogen, and R b It is an alkyl group.

[0044] In some embodiments, n is 1 to 6.

[0045] In some embodiments, the alkylsilane compound is given by the following formula: TIFF2026509373000021.tif48170 or TIFF2026509373000022.tif42170 or TIFF2026509373000023.tif50170 or TIFF2026509373000024.tif50170 or TIFF2026509373000025.tif49170[In the formula, R 4 , R 5 and R 6 These are compounds of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, and their isomers.

[0046] In some embodiments, the composition contains 75% to 90% by weight of phosphoric acid based on the total weight of the composition, or any range or subrange between 75% and 90%. For example, in some embodiments, the weight percentage of phosphoric acid based on the total weight of the composition may be 80% to 90% or 85% to 90%. In some embodiments, the weight percentage of phosphoric acid based on the total weight of the composition may be 76% to 90%, 77% to 90%, 78% to 90%, 79% to 90%, 80% to 90%, 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 phosphoric acid based on the total weight of the wet etch composition may be 75%-89%, 75%-88%, 75%-87%, 75%-86%, 75%-85%, 75%-84%, 75%-83%, 75%-82%, 75%-81%, 75%-80%, 75%-79%, 75%-78%, 75%-77%, or 75%-76%.

[0047] In some embodiments, the composition contains 10% to 20% by weight of water based on the total weight of the composition, or any range or subrange between 1% and 20%. For example, in some embodiments, the percentage by weight of water based on the total weight of the composition may be 1% to 15%, 1% to 10%, or 5% to 20%. In some embodiments, the percentage by weight of water based on the total weight of the 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 water relative to the total weight of the composition may be 1%-19%, 1%-18%, 1%-17%, 1%-16%, 1%-15%, 1%-14%, 1%-13%, 1%-12%, 1%-11%, 1%-10%, 1%-9%, 1%-8%, 1%-7%, 1%-6%, 1%-5%, 1%-4%, 1%-3%, or 1%-2%.

[0048] In some embodiments, the composition contains 0.01% to 5% by weight of the alkylsilane compound based on the total weight of the composition, or any range or subrange between 0.01% and 5%. For example, in some embodiments, the weight % of the alkylsilane compound based on the total weight of the 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 % of the alkylsilane compound based on the total weight of the composition may be 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 percentage of the alkylsilane compound based on the total weight of the 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 the alkylsilane compound based on the total weight of the composition may be 0.01% to 5%, 0.01% to 4.5%, 0.01% to 4%, 0.01% to 3.5%, 0.01% to 3%, 0.01% to 2.5%, 0.01% to 2%, 0.01% to 1.5%, 0.01% to 1%, 0.01% to 0.5%, or 0.01% to 0.1%.

[0049] Figure 1 is a flowchart of method 100 for selectively etching silicon nitride according to several embodiments. As shown in Figure 1, method 100 may include one or more of the following steps: a step 102 to obtain a structure comprising silicon nitride and silicon oxide; and a step 104 to contact the structure with a composition that removes at least a portion of the silicon nitride.

[0050] In some embodiments, the structure in step 102 may be a part of a microelectronic device, which is, for example, a 3D NAND structure, a flat panel display, a micro-electromechanical system (MEMS), an integrated circuit, or a computer chip.

[0051] In some embodiments, contact in step 104 includes direct contact, or bringing it close to or near the object. In some embodiments, contact includes placing, depositing, applying, or dropwise adding the composition onto the structure. In some embodiments, contact is performed under heating.

[0052] In some embodiments, the contacting in step 104 is carried out at a temperature between 25°C and 180°C, or within any range or subrange between 25°C and 180°C. For example, in some embodiments, the temperature may be 30°C to 180°C, 40°C to 180°C, 50°C to 180°C, 60°C to 180°C, 70°C to 180°C, 80°C to 180°C, 90°C to 180°C, 100°C to 180°C, 110°C to 180°C, 120°C to 180°C, 130°C to 180°C, 140°C to 180°C, 150°C to 180°C, 160°C to 180°C, or 170°C to 180°C. In some embodiments, the temperature ranges are 25°C to 180°C, 30°C to 180°C, 35°C to 180°C, 40°C to 180°C, 45°C to 180°C, 50°C to 180°C, 55°C to 180°C, 60°C to 180°C, 65°C to 180°C, 70°C to 180°C, 75°C to 180°C, 80°C to 180°C, 85°C to 180°C, 90°C to 180°C, 95°C to 180°C, and 100°C to 180°C. The temperature range may be 105°C to 180°C, 110°C to 180°C, 115°C to 180°C, 120°C to 180°C, 125°C to 180°C, 130°C to 180°C, 135°C to 180°C, 140°C to 180°C, 145°C to 180°C, 150°C to 180°C, 155°C to 180°C, 160°C to 180°C, 165°C to 180°C, 170°C to 180°C, or 175°C to 180°C. In some embodiments, the temperature is 25℃~180℃, 25℃~175℃, 25℃~170℃, 25℃~165℃, 25℃~160℃, 25℃~155℃, 25℃~150℃, 25℃~145℃, 25℃~140℃, 25℃~135℃, 25℃~130℃, 25℃~125℃, 25℃~120℃, 25℃~115℃, 25℃ You may also use temperatures below 110°C, 25°C-105°C, 25°C-100°C, 25°C-95°C, 25°C-90°C, 25°C-85°C, 25°C-80°C, 25°C-75°C, 25°C-70°C, 25°C-65°C, 25°C-60°C, 25°C-55°C, 25°C-50°C, 25°C-45°C, 25°C-40°C, 25°C-35°C, or 25°C-30°C.

[0053] In some embodiments, the portion of silicon nitride removed in step 104 is at least 80%. In some embodiments, the portion of silicon nitride removed is at least 85%, at least 90%, at least 95%, or at least 99%.

[0054] In some embodiments, the composition includes phosphoric acid, water, and the following formula: TIFF2026509373000026.tif35170[in the formula, R 1 , R 2 and R 3 Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide, n is at least 1, and Q is TIFF2026509373000027.tif42170 or TIFF2026509373000028.tif32170[In the formula, R a and R b Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl, and R c [The alkylsilane compound is hydrogen, alkyl, cycloalkyl, aryl, or alkaryl] Includes.

[0055] In some embodiments, R 1 , R 2 and R 3 These are methoxy compounds, respectively.

[0056] In some embodiments, R a and R b It is hydrogen.

[0057] In some embodiments, R a is hydrogen, and R b It is an alkyl group.

[0058] In some embodiments, n is 1 to 6.

[0059] In some embodiments, the alkylsilane compound is given by the following formula: TIFF2026509373000029.tif48170 or TIFF2026509373000030.tif42170 or TIFF2026509373000031.tif50170 or TIFF2026509373000032.tif50170 or TIFF2026509373000033.tif49170[In the formula, R 4 , R 5 and R 6 These are compounds of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, and their isomers.

[0060] In some embodiments, the composition contains 75% to 90% by weight of phosphoric acid based on the total weight of the composition, or any range or subrange between 75% and 90%. For example, in some embodiments, the weight percentage of phosphoric acid based on the total weight of the composition may be 80% to 90% or 85% to 90%. In some embodiments, the weight percentage of phosphoric acid based on the total weight of the composition may be 76% to 90%, 77% to 90%, 78% to 90%, 79% to 90%, 80% to 90%, 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 phosphoric acid based on the total weight of the composition may be 75%-89%, 75%-88%, 75%-87%, 75%-86%, 75%-85%, 75%-84%, 75%-83%, 75%-82%, 75%-81%, 75%-80%, 75%-79%, 75%-78%, 75%-77%, or 75%-76%.

[0061] In some embodiments, the composition contains 10% to 20% by weight of water based on the total weight of the composition, or any range or subrange between 1% and 20%. For example, in some embodiments, the percentage by weight of water based on the total weight of the composition may be 1% to 15%, 1% to 10%, or 5% to 20%. In some embodiments, the percentage by weight of water relative to the total weight of the 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 water relative to the total weight of the composition may be 1%-19%, 1%-18%, 1%-17%, 1%-16%, 1%-15%, 1%-14%, 1%-13%, 1%-12%, 1%-11%, 1%-10%, 1%-9%, 1%-8%, 1%-7%, 1%-6%, 1%-5%, 1%-4%, 1%-3%, or 1%-2%.

[0062] In some embodiments, the composition contains 0.01% to 5% by weight of the alkylsilane compound based on the total weight of the composition, or any range or subrange between 0.1% and 5%. For example, in some embodiments, the weight % of the alkylsilane compound based on the total weight of the composition may be 1% to 5%, 2% to 5%, 3% to 5%, or 4% to 5%. In some embodiments, the weight % of the alkylsilane compound based on the total weight of the composition may be 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 % of the alkylsilane compound based on the total weight of the 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 percent of the alkylsilane compound based on the total weight of the 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%.

[0063] In some embodiments, the composition removes a larger proportion of silicon nitride than silicon oxide.

[0064] Figure 2 illustrates the results of the method of Figure 1 according to several embodiments. As shown in Figure 2, a microelectronic structure having silicon dioxide 202 is subjected to composition 210. Composition 210 may include any of the compositions disclosed herein. In some embodiments, the microelectronic structure may be a part of a microelectronic device, which is, for example, a 3D NAND structure, a flat panel display, a micro-electromechanical system (MEMS), an integrated circuit, or a computer chip, without limitation. [Examples]

[0065] The improved composition was prepared according to the above formulation, and its performance was compared with that of the control composition.

[0066] The improved and control compositions were filled into graduated cylinders at room temperature, and nitrogen gas was injected into the solution for 1 minute through a nitrogen gas bubbler. The amount and height of the bubbles produced were measured and compared, and the results are shown in Table 1 below. TIFF2026509373000034.tif22170

[0067] As shown in the table, the improved composition significantly improved foam height compared to the control composition. The improved composition had a silicon nitride etch rate of 100 angstroms per minute. The improved composition had a silicon oxide etch rate of 0.17 angstroms per minute. Therefore, the improved composition had a silicon nitride selectivity of 580 for silicon oxide. This is preferably comparable to a selectivity of 57 for 85% phosphoric acid.

[0068] manner Various embodiments are described below. It will be understood that one or more of the features listed in the following embodiments may be combined with any one or more other embodiments. Appearance 1. Phosphoric acid; Water; and The following formula TIFF2026509373000035.tif35170[In the formula, R 1 , R 2 and R 3 Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide; n is at least 1; Q is, TIFF2026509373000036.tif42170 or TIFF2026509373000037.tif32170[In the formula, R a and R b Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl; R c is an alkylsilane compound that is hydrogen, alkyl, cycloalkyl, aryl or alkaryl A composition comprising. Aspect 2. R 1 , R 2 and R 3 are each methoxy, the composition according to aspect 1. Aspect 3. R a and R b are hydrogen, the composition according to aspect 1 or 2. Aspect 4. R a is hydrogen and R b is alkyl, the composition according to any one of aspects 1 to 3. Aspect 5. n is from 1 to 6, the composition according to any one of aspects 1 to 4. Aspect 6. The alkylsilane compound is of the following formula TIFF2026509373000038.tif48170 or TIFF2026509373000039.tif42170 or TIFF2026509373000040.tif50170 or TIFF2026509373000041.tif50170 or TIFF2026509373000042.tif49170[wherein, R 4 , R 5 and R 6 are independently methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, their isomers] compounds, the composition according to any one of aspects 1 to 5. Aspect 7. The composition according to any one of aspects 1 to 6, comprising 75% to 90% by weight of phosphoric acid based on the total weight of the composition. Aspect 8. The composition according to any one of aspects 1 to 7, comprising 10% to 20% by weight of water based on the total weight of the composition. Aspect 9. The composition according to any one of aspects 1 to 8, comprising 0.01% to 5% by weight of an alkylsilane compound based on the total weight of the composition. A composition according to any one of embodiments 1 to 9, which, when mixed at 25°C to 160°C at 200 RPM, produces less foam than a composition that does not contain an alkylsilane compound. Embodiment 11. Obtaining a structure containing silicon nitride and silicon oxide, The structure is brought into contact with the composition to remove at least a portion of the silicon nitride. A method including, Here, the composition is phosphoric acid; Water; and The following formula TIFF2026509373000043.tif35170[In the formula, R 1 , R 2 and R 3 Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide; n is at least 1, Q is, TIFF2026509373000044.tif42170 or TIFF2026509373000045.tif32170[in the formula, R a and R b Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkalil, aralkyl, or alkoxyalkyl, R c [The alkylsilane compound is hydrogen, alkyl, cycloalkyl, aryl, or alkaryl] Methods that include... Appearance 12.R 1 , R 2 and R 3 The method according to embodiment 11, wherein each of them is methoxy. Appearance 13.R a and R b The method according to embodiment 11 or 12, wherein the hydrogen is... Appearance 14.R a However, it is hydrogen, and R bThe method according to any one of embodiments 11 to 13, wherein the alkyl is The method according to any one of embodiments 11 to 14, wherein embodiment 15.n is 1 to 6. Embodiment 16. The alkylsilane compound is the following formula TIFF2026509373000046.tif48170 or TIFF2026509373000047.tif42170 or TIFF2026509373000048.tif50170 or TIFF2026509373000049.tif50170 or TIFF2026509373000050.tif49170[In the formula, R 4 , R 5 and R 6 The composition according to any one of embodiments 11 to 55, wherein is independently a compound of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, or their isomers. Embodiment 17. The method according to any one of Embodiments 11 to 16, wherein the composition contains 75% to 90% by weight of phosphoric acid based on the total weight of the composition. Embodiment 18. The method according to any one of Embodiments 11 to 17, wherein the composition contains 10% to 20% by weight of water based on the total weight of the composition. Embodiment 19. The method according to any one of Embodiments 11 to 18, wherein the composition comprises 0.01% to 5% by weight of an alkylsilane compound based on the total weight of the composition. Embodiment 20. The method according to any one of Embodiments 11 to 19, wherein the composition removes silicon nitride in a proportion greater than that of silicon oxide. In particular, it will be understood that detailed modifications to the construction materials used, as well as the shape, size, and arrangement of components, may be made without departing from the scope of this disclosure. The embodiments described herein are illustrative, and the true scope and spirit of this disclosure are shown by the subsequent claims.

Claims

1. phosphoric acid; water; and The following formula [In the formula, R １ , R ２ and R ３ Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide; n is at least 1; Q is, or (In the formula, R ａ and R ｂ Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl; R ｃ Alkylsilane compounds (which are hydrogen, alkyl, cycloalkyl, aryl, or alkaryl) A composition containing the following:

2. R １ 、 R ２ and R ３ are each methoxy, the composition according to claim 1.

3. R ａ and R ｂ The composition according to claim 1, wherein the hydrogen is hydrogen.

4. R ａ However, it is hydrogen, R ｂ The composition according to claim 1, wherein the element is alkyl.

5. The composition according to claim 1, wherein n is 1 to 6.

6. Alkylsilane compounds are, or or or or [In the formula, R ４ , R ５ and R ６ The composition according to claim 1, wherein is independently a compound of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, or their isomers.

7. The composition according to claim 1, comprising 75% to 90% by weight of phosphoric acid based on the total weight of the composition.

8. The composition according to claim 1, comprising 10% to 20% by weight of water based on the total weight of the composition.

9. The composition according to claim 1, comprising 0.01% to 5% by weight of an alkylsilane compound based on the total weight of the composition.

10. The composition according to claim 1, which, when mixed at 25°C to 160°C at 200 RPM, produces less foam than a composition that does not contain an alkylsilane compound.

11. To obtain a structure containing silicon nitride and silicon oxide; The structure is brought into contact with the composition to remove at least a portion of the silicon nitride. A method including, Here, the composition is phosphoric acid; Water; and The following formula [In the formula, R １ , R ２ and R ３ Each of these is independently hydrogen, a halide, a hydroxide, an alkyl, or an alkoxide; n is at least 1; Q is, or (In the formula, R ａ and R ｂ Each of these is independently hydrogen, alkyl, cycloalkyl, aryl, alkaryl, aralkyl, or alkoxyalkyl; R ｃ Alkylsilane compounds (which are hydrogen, alkyl, cycloalkyl, aryl, or alkaryl) Methods that include...

12. R １ , R ２ and R ３ The method according to claim 11, wherein each of them is methoxy.

13. R ａ and R ｂ The method according to claim 11, wherein the hydrogen is...

14. R ａ However, it is hydrogen, R ｂ The method according to claim 11, wherein the component is alkyl.

15. The method according to claim 11, wherein n is 1 to 6.

16. Alkylsilane compounds are, or or or or [In the formula, R ４ , R ５ and R ６ The method according to claim 11, wherein is independently a compound of methyl, ethyl, isopropyl, n-propyl, n-butyl, sec-butyl, tert-butyl, or their isomers.

17. The method according to claim 11, wherein the composition comprises 75% to 90% by weight of phosphoric acid based on the total weight of the composition.

18. The method according to claim 11, wherein the composition contains 10% to 20% by weight of water based on the total weight of the composition.

19. The method according to claim 11, wherein the composition comprises 0.01% to 5% by weight of an alkylsilane compound based on the total weight of the composition.

20. The method according to claim 11, wherein the composition removes silicon nitride in a proportion greater than that of silicon oxide.

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