Etching Composition and Etching Method for Selectively Removing Silicon Nitride during Semiconductor Element Manufacturing

Abstract

To provide an etching composition containing a mixture of (A) phosphoric acid and (B) a silicon-containing compound (i) and an aqueous solvent (ii).SOLUTION: In some embodiments, this etching composition contains additional components. The etching compositions are useful for selectively removing silicon nitride from a microelectronic element having silicon nitride or silicon oxide rather than silicon oxide during manufacture of the microelectronic element.SELECTED DRAWING: None

Description

Technical Field

[0001] Field

[0002] The subject matter of the present disclosure and the present claims relates to an etching composition, and more specifically, to a highly selective etching composition capable of selectively removing a nitride film while minimizing the etching rate of an oxide film, and a method for semiconductor manufacturing including an etching process using the etching composition.

Background Art

[0003] Related Art

[0004] The selective removal of sacrificial silicon nitride (SiN x ) is one of the important processes in the manufacture of 3D-NAND memory devices. After the etching process, SiN x is removed and the silicon oxide (SiO x ) core of the fin structure that has not changed remains. Conventionally, SiN x etching can be achieved by hot phosphoric acid at 160°C, but the selectivity of SiN x etching compared to silicon or silicon oxide materials is generally low for advanced 3D-NAND memory technology. x As the integration density of semiconductor devices increases, the reliability and electrical characteristics of those semiconductor devices are likely to be affected by damage or deformation of the layers constituting those semiconductor devices. Therefore, when performing an etching process to selectively remove a specific material layer using an etching solution, it is desirable that the etching solution has a high etching selectivity with respect to other material layers and reduces process defects by reducing by-products generated by the etching process.

[0005] As the integration density of semiconductor devices increases, the reliability and electrical characteristics of those semiconductor devices are likely to be affected by damage or deformation of the layers constituting those semiconductor devices. Therefore, when performing an etching process to selectively remove a specific material layer using an etching solution, it is desirable that the etching solution has a high etching selectivity with respect to other material layers and reduces process defects by reducing by-products generated by the etching process.

Summary of the Invention

Problems to be Solved by the Invention

[0006] Therefore, at such a high integration density, sacrificial SiN in 3D-NAND manufacturingx The importance of the material selectivity requirement for selective removal increases, and while etching the SiN x layer, it is desirable to effectively leave the SiO x layer unchanged. Therefore, in the art, it is required to further suppress the SiO x etching rate to achieve a higher SiN x selectivity than SiO x etching rate.

Means for Solving the Problem

[0007] In one aspect, the subject matter of the present disclosure and the claims is an etching composition suitable for the selective removal of silicon nitride over silicon oxide from a microelectronic device, (A) phosphoric acid, and (B) a mixture comprising an aqueous solvent and a silicon-containing compound (which may also be referred to as an organosilicon compound) is provided.

[0008] In some embodiments, the silicon-containing compound has formula I,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0009] In some embodiments, the silicon - containing compound has the formula II,

Chemical formula

Chemical formula

[0010] In some embodiments, the silicon-containing compound has formula III: [ka] During the ceremony, (i) m1 and m2 are each equal to 0 to 10, provided that at least one of m1 and m2 is 1 or greater; (ii) n=0 or 1, (iii)R 1 , R 2 , and R3 each is independently hydrogen, a C1-C6 linear alkyl group, a C3-C6 branched alkyl group, and

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chem.

Chem.

Chem.

Chem.

Chem.

[0011] In some embodiments, the etching composition comprises up to about 70 wt% pure phosphoric acid. In other aspects of this embodiment, the etching composition comprises up to about 60 wt% pure phosphoric acid. In other aspects of this embodiment, the etching composition comprises at least about 30 wt% of the mixture. In other aspects of this embodiment, the etching composition comprises at least about 40 wt% of the mixture. In other aspects of this embodiment, the pure phosphoric acid and the mixture together constitute about 100 wt% of the etching composition.

[0012] In some embodiments, the etching composition comprises more than about 70 wt% pure phosphoric acid. In other aspects of this embodiment, the etching composition comprises more than about 75 wt% pure phosphoric acid. In other aspects of this embodiment, the etching composition comprises up to about 30 wt% of the mixture. In other aspects of this embodiment, the etching composition comprises at least about 25 wt% of the mixture. In other aspects of this embodiment, the pure phosphoric acid and the mixture together constitute about 100 wt% of the etching composition.

[0013] In some embodiments, the mixture further comprises at least one additional acid other than phosphoric acid. In one aspect of this embodiment, this at least one additional acid is one of nitric acid (HNO3), sulfuric acid (H2SO4), hydrochloric acid (HCl), and sulfonic acid (such as methanesulfonic acid (CH3SO3H)). In other aspects, this at least one additional acid comprises sulfuric acid.

[0014] In another aspect, the subject matter of the present disclosure and the claims is a method for selectively improving the etching rate of silicon nitride compared to silicon dioxide on a composite semiconductor device comprising silicon nitride and silicon dioxide, the method comprising contacting the composite semiconductor device comprising silicon nitride and silicon dioxide with the etching composition.

[0015] In some embodiments, the compounds of Formula I, Formula II, and / or Formula III can include additional selectable groups such as epoxy groups, styryl groups, metasiloxy groups, acyloxy groups, ureido groups, isocyanato groups, isocyanurate groups, and mercapto groups at one or more hydrogen positions.

[0016] These embodiments of the subject matter of the present disclosure and the claims may be used alone or in combination with each other.

Embodiments for Carrying Out the Invention

[0017] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference in their entirety to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0018] As used in the context of this disclosure and the description of the subject matter of the claims (in particular the following claims), the terms "a", "an", and "the", and similar designators, should be construed to include both the singular and the plural unless otherwise indicated herein or clearly contradicted by the context. The terms "comprising", "having", "including", and "containing" should be construed as non-limiting terms (i.e., meaning "including but not limited to") unless otherwise stated. The recitation of a range of values herein is intended merely as a convenient way to refer individually to each value falling within the range, and each value is incorporated herein as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by the context. The use of any and all examples or exemplary language (e.g., "such as") presented herein is merely intended to better illustrate the disclosure and the subject matter of the claims and is not intended to limit the scope of the disclosure and the subject matter of the claims unless otherwise claimed in the claims. There is no expression in this specification to be construed as indicating an element not claimed in the claims as essential to the practice of the subject matter of the disclosure and the claims.

[0019] The preferred embodiments of the present disclosure and the subject matter of the present claims are described herein and include the best mode known to the inventors for carrying out the present disclosure and the subject matter of the present claims. Variations of these preferred embodiments may become apparent to those skilled in the art upon reading the foregoing description. The inventors expect those skilled in the art to use these variations as appropriate, and the inventors intend that the present disclosure and the subject matter of the present claims be practiced in a manner different from that specifically described herein. Accordingly, the present disclosure and the subject matter of the present claims include all modifications and equivalents of the subject matter enumerated in the claims appended hereto as permitted by applicable law. Also, all combinations of those elements in all possible variations of the above elements are included in the present disclosure and the subject matter of the present claims unless otherwise indicated herein or unless clearly precluded from the context.

[0020] The present disclosure and the subject matter of the present claims generally relate to compositions useful for selectively removing silicon nitride over silicon oxide from microelectronic devices having silicon nitride and silicon oxide during the manufacture of the microelectronic devices.

[0021] For ease of reference, a "microelectronic device" or "semiconductor substrate" corresponds to semiconductor wafers, flat panel displays, phase change memory devices, solar panels, and other products including solar substrates, photovoltaic power, and microelectromechanical systems (MEMS) manufactured for use in microelectronic applications, integrated circuit applications, or computer chip applications. Solar substrates include, but are not limited to, silicon, amorphous silicon, polycrystalline silicon, monocrystalline silicon, CdTe, copper indium selenide, copper indium sulfide, and gallium arsenide. The solar substrate may be doped or undoped. It should be understood that the term "microelectronic device" has no more or less limited meaning and ultimately includes any substrate that becomes a microelectronic device or microelectronic assembly. These microelectronic devices or semiconductor substrates may include low dielectric constant (k) dielectric materials, barrier materials, and metals such as AlCu alloys, W, Ti, TiN, and other materials on the microelectronic device or semiconductor substrate.

[0022] As defined herein, a "low dielectric constant (k) dielectric material" corresponds to any material having a dielectric constant of less than about 3.5 used as a dielectric material in a layered microelectronic device. These low dielectric constant (k) dielectric materials preferably include low polarity materials such as silicon-containing organic polymers, silicon-containing organic / inorganic hybrid materials, organosilicate glass (OSG), TEOS, fluorine-doped silicate glass (FSG), silicon dioxide, and carbon-doped oxide (CDO) glass. It should be understood that these low dielectric constant (k) dielectric materials can have various densities and various porosities.

[0023] As defined herein, the term "barrier material" corresponds to any material used in the art to seal a metal wire, such as a copper wiring, in order to minimize the diffusion of the metal, such as copper, into the dielectric material. Preferred barrier layer materials include tantalum, titanium, ruthenium, hafnium, and other refractory metals, as well as nitrides and silicides thereof.

[0024] As used herein, "substantially free" is defined as less than 2% by mass, preferably less than 1% by mass, more preferably less than 0.5% by mass, and most preferably less than 0.1% by mass. "Substantially free" includes 0.0% by mass. The term "free" means 0.0% by mass.

[0025] As used herein, the terms "about" and "approximately" are each intended to correspond to ±5% of the indicated value.

[0026] As used herein, "pure" refers to the amount in mass % of an undiluted acid or other material. For example, what is contained in 100 g of 85% phosphoric acid is composed of 85 g of the acid and 15 grams of a diluent.

[0027] In addition to the representations known and understood as covalent bond attachment points

Chemical formula

[0028] In all such compositions where a particular component of the composition is discussed with reference to a mass percentage range that includes a zero lower limit, it should be understood that such a component may or may not be present in various specific embodiments of the composition, and in examples where such components are present, those components may be present at a low concentration of as little as 0.001 mass percent relative to the total mass of the composition in which such components are used. It should be noted that all specified mass percentages of these components are based on the total mass of the composition unless otherwise indicated. Further, all mass percentages are "pure" unless otherwise indicated, meaning that they do not include aqueous compositions in which these components are added to the composition and in which these components are present. Whenever "at least 1" is referred to, it can always be replaced with "1 or more". "At least 1" or "1 or more" includes "at least 2" or "2 or more" and "at least 3" or "3 or more", etc.

[0029] Broadly speaking, the disclosed and claimed embodiments are directed to an etching composition as described above that comprises, consists essentially of, or consists of a mixture of (A) phosphoric acid and (B) a silicon-containing compound disclosed herein and an aqueous solvent. In some embodiments, the etching composition can include other components.

[0030] In some embodiments, the etching composition disclosed herein is formulated to be substantially free of at least one of the following compounds: hydrogen peroxide and other peroxides, ammonium ions, fluoride ions, inorganic bases, quaternary ammonium hydroxides, metal-containing compounds, and abrasives.

[0031] In other embodiments, the etching composition consists essentially of (i) phosphoric acid and (ii) the mixture of the silicon-containing compound disclosed herein and the aqueous solvent. In such embodiments, the total amount of (i) and (ii) is not equal to 100 mass%, and the etching composition can include other components that do not substantially change the effectiveness of the etching composition.

[0032] In another embodiment, the etching composition consists of (i) phosphoric acid and (ii) the silicon-containing compounds disclosed herein at various concentrations and the aqueous solvent. In such an embodiment, the total amount of (i) and (ii) is equal to 100% by mass, but may contain small amounts and / or trace amounts of other impurities present in such small amounts that do not substantially change the effectiveness of the composition. For example, in one such embodiment, the etching composition may contain 2% by mass or less of impurities. In another embodiment, the etching composition may contain 1% by mass or less of impurities. In other embodiments, the etching composition may contain 0.05% by mass or less of impurities.

[0033] When referring to the composition of the compositions of the present invention described herein in terms of mass%, it is understood that the mass% of all components including non-essential components such as impurities is never added up to exceed 100% by mass. In a composition "consisting essentially of" the recited components, such components may be added up to 100% by mass of the composition or may be added up to less than 100% by mass. When these components are added up to less than 100% by mass, such a composition may contain some small amounts of non-essential contaminants or impurities. For example, in one such embodiment, the etching composition may contain 2% by mass or less of impurities. In another embodiment, the etching composition may contain 1% by mass or less of impurities. In other embodiments, the etching composition may contain 0.05% by mass or less of impurities. In other such embodiments, the components can be at least 90% by mass, more preferably at least 95% by mass, more preferably at least 99% by mass, more preferably at least 99.5% by mass, most preferably at least 99.9% by mass, and can contain other components that do not substantially affect the performance of the etching composition. Alternatively, it is understood that when there are no important non-essential impurity components, the combination of all essential components is basically added up to 100% by mass.

[0034] Composition

[0035] As described above, the subject matter of the present disclosure and the present claims relates to an etching composition comprising, consisting essentially of, or consisting of a mixture of (A) phosphoric acid and (B) a silicon-containing compound disclosed herein and an aqueous solvent. In some embodiments, the etching composition may include other components.

[0036] Component

[0037] (A) Phosphoric acid

[0038] The etching composition of the subject matter of the present disclosure and the present claims contains phosphoric acid. Commercial quality phosphoric acid can be used. This commercially available phosphoric acid is typically available as an 80% - 85% aqueous composition. In a preferred embodiment, an electronics grade phosphoric acid composition is used. Such electronics grade compositions typically have 100 particles / ml or less in terms of the number of particles, the size of those particles is 0.5 microns or less, and metal ions are present in the acid at a low parts per million to low parts per billion level per liter. In certain embodiments, other inorganic acids, such as hydrofluoric acid, nitric acid, or mixtures thereof, etc., are not added to the composition of the subject matter of the present disclosure and the present claims.

[0039] The phosphoric acid is included in an amount within a range having a starting point and an end point selected from the following list of mass percentages (on a pure basis), i.e., about 40 mass% to about 95 mass%, about 45 mass% to about 90 mass%, or about 50 mass% to about 90 mass%, or about 55 mass% to about 85 mass% of the composition. This phosphoric acid may be present in amounts defined by the following list of mass percentages, i.e., 30%, 35%, 37%, 40%, 42%, 45%, 47%, 50%, 52%, 55%, 57%, 60%, 62%, 65%, 68%, 70%, 72%, 75%, 78%, 80%, 82%, 85%, 88%, 90%, 92%, and 95%.

[0040] In some embodiments, the content of the pure phosphoric acid is about 70% by mass or less. In other aspects of this embodiment, the content of the pure phosphoric acid is about 60% by mass or less.

[0041] In some embodiments, the content of the pure phosphoric acid is more than about 70% by mass. In other aspects of this embodiment, the content of the pure phosphoric acid is more than about 75% by mass.

[0042] (B) Mixture

[0043] As described above, the etching composition contains a mixture of (I) a silicon-containing compound disclosed herein and (II) an aqueous solvent.

[0044] I. Silicon-containing compound

[0045] The amount of the silicon-containing compound ranges from about 0.001% by mass to about 15% by mass of the etching composition. The silicon-containing compound preferably constitutes about 0.1% by mass to about 10% by mass of the etching composition. These mass percentages, including the stated mass percentage of the silicon-containing compound converted to the composition, are on a pure substance basis unless otherwise indicated. In alternative embodiments, the silicon-containing compound is present in an amount within a range having a starting point and an end point defined by the following list of mass percentages, namely 0.001, 0.01%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.2%, 1.5%, 1.7%, 2%, 2.2%, 2.5%, 2.7%, 3%, 3.2%, 3.5%, 3.7%, 4%, 4.2%, 4.5%, 4.7%, 5%, 5.2%, 5.5%, 5.7%, 6%, 6.2%, 6.5%, 6.8%, 7%, 7.2%, 7.5%, 7.8%, 8%, 8.2%, 8.5%, 8.8%, 9%, 9.2%, 9.5%, 10%, 12%, 15%, 17%, and 20%.

[0046] In some embodiments, the silicon-containing compound has Formula I,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0047] In some embodiments of the etching composition containing the silicon - containing compound of Formula I, each of R 1 , R 2 , R 3 , R 4 , and R 5 is the same. In other aspects of this embodiment, R 1 , R2 , R 3 , R 4 , and R 5 are each hydrogen.

[0048] In some embodiments of the etching composition comprising the silicon-containing compound of Formula I, R 1 , R 2 , R 3 , R 4 , and R 5 at least one of is other than hydrogen.

[0049] In some embodiments of the etching composition comprising the silicon-containing compound of Formula I, m is from 0 to 20. In other aspects of this embodiment, m is 0. In other aspects of this embodiment, m is 1. In other aspects of this embodiment, m is 2. In other aspects of this embodiment, m is 3. In other aspects of this embodiment, m is 4. In other aspects of this embodiment, m is 5. In other aspects of this embodiment, m is 6. In other aspects of this embodiment, m is 7. In other aspects of this embodiment, m is 8. In other aspects of this embodiment, m is 9. In other aspects of this embodiment, m is 10. In other aspects of this embodiment, m is 11. In other aspects of this embodiment, m is 12. In other aspects of this embodiment, m is 13. In other aspects of this embodiment, m is 14. In other aspects of this embodiment, m is 15. In other aspects of this embodiment, m is 16. In other aspects of this embodiment, m is 17. In other aspects of this embodiment, m is 18. In other aspects of this embodiment, m is 19. In other aspects of this embodiment, m is 20.

[0050] In some embodiments of the etching composition, the content of the silicon-containing compound of Formula I is about 5% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula I is about 4% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula I is about 3% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula I is about 2% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula I is about 1% by mass or less.

[0051] In some embodiments, the etching composition is (i) R a and R b each being

Chemical formula

Chemical formula

[0052] In some embodiments, the etching composition is (i) R a and R b each being

Chemical formula

Chemical formula

Chemical formula

[0053] In some embodiments, the etching composition comprises (i) R a and R b each of which is [Chemical formula] and (ii) R 1 , R 2 , R 3 , R 4 , and R 5 each of which is [Chemical formula] and (iii) the silicon-containing compound of Formula I where m = 0.

[0054] In some embodiments, the silicon-containing compound has Formula II [Chemical formula] wherein (i) m = 0 to 20, (ii) n = 0 to 20, (iii) R 3 is hydrogen, a C1-C 10 linear alkyl group, a fluorine-substituted C1-C 10 linear alkyl group, a nitrogen-containing group, an oxygen-containing group, a C3-C 10 branched alkyl group, a C3-C 10 cyclic alkyl group, a C5-C 12 aryl group, a C2-C 10 linear or branched alkenyl group and a C2-C 10 linear or branched alkynyl group, [Chemical formula] Z 1 and Z 2 are selected from the group consisting of, and (iv) each of R a and R b is independently a C1-C 10 linear alkyl group, a C3-C 10 branched alkyl group, a C3-C10 Cyclic alkyl group, C5 - C 12 Aryl group, C2 - C 10 Straight-chain or branched alkenyl group, C2 - C 10 Straight-chain or branched alkynyl group,

Chem.

Chem.

Chem.

Chem.

Chem.

Chem.

[0055] In some embodiments of the etching composition comprising the silicon-containing compound of Formula II, m is from 0 to 20. In other aspects of this embodiment, m is 0. In other aspects of this embodiment, m is 1. In other aspects of this embodiment, m is 2. In other aspects of this embodiment, m is 3. In other aspects of this embodiment, m is 4. In other aspects of this embodiment, m is 5. In other aspects of this embodiment, m is 6. In other aspects of this embodiment, m is 7. In other aspects of this embodiment, m is 8. In other aspects of this embodiment, m is 9. In other aspects of this embodiment, m is 10. In other aspects of this embodiment, m is 11. In other aspects of this embodiment, m is 12. In other aspects of this embodiment, m is 13. In other aspects of this embodiment, m is 14. In other aspects of this embodiment, m is 15. In other aspects of this embodiment, m is 16. In other aspects of this embodiment, m is 17. In other aspects of this embodiment, m is 18. In other aspects of this embodiment, m is 19. In other aspects of this embodiment, m is 20.

[0056] In some embodiments of the etching composition comprising the silicon-containing compound of Formula II, n is from 0 to 20. In other aspects of this embodiment, n is 0. In other aspects of this embodiment, n is 1. In other aspects of this embodiment, n is 2. In other aspects of this embodiment, n is 3. In other aspects of this embodiment, n is 4. In other aspects of this embodiment, n is 5. In other aspects of this embodiment, n is 6. In other aspects of this embodiment, n is 7. In other aspects of this embodiment, n is 8. In other aspects of this embodiment, n is 9. In other aspects of this embodiment, n is 10. In other aspects of this embodiment, n is 11. In other aspects of this embodiment, n is 12. In other aspects of this embodiment, n is 13. In other aspects of this embodiment, n is 14. In other aspects of this embodiment, n is 15. In other aspects of this embodiment, n is 16. In other aspects of this embodiment, n is 17. In other aspects of this embodiment, n is 18. In other aspects of this embodiment, n is 19. In other aspects of this embodiment, n is 20.

[0057] In some embodiments of the etching composition, the content of the silicon-containing compound of Formula II is about 5% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula II is about 4% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula II is about 3% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula II is about 2% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula II is about 1% by mass or less.

[0058] In some embodiments, the etching composition comprises the silicon-containing compound of Formula II.

[0059] In some embodiments, the etching composition is such that (i) m = 0 and (ii) each of Z 1 and Z 2 is

Chemical formula

[0060] In some embodiments, the etching composition is such that (i) m = 0, (ii) n = 0, and (iii) each of Z 1 and Z 2 is

Chemical formula

[0061] In some embodiments, the etching composition is such that (i) m = 0, (ii) n = 0, and (iii) each of Z 1 and Z 2 is

Chemical formula

[0062] In some embodiments, the etching composition is such that (i) m = 0, (ii) n = 0, and (iii) each of Z 1 and Z 2 is

Chemical formula

[0063] In some embodiments, the silicon-containing compound has formula III,

Chemical formula

Chem.

Chem.

Chem.

Chem.

Chem.

[0064] In some embodiments of the etching composition, the content of the silicon-containing compound of Formula III is about 5% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula III is about 4% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula III is about 3% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula III is about 2% by mass or less. In other aspects of this embodiment, the content of the silicon-containing compound of Formula III is about 1% by mass or less.

[0065] In some embodiments, the etching composition is (i) each of R 1 , R 2 , and R 3 is

Chem.

Chem.

[0066] In some embodiments, the etching composition comprises (i) R 1 , R 2 , and R 3 each being

Chemical formula

Chemical formula

[0067] In some embodiments, the etching composition comprises (i) R 1 , R 2 , and R 3 each being

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0068] In some embodiments, the etching composition comprises (i) each of R 1 , R 2 , and R 3 is

Chemical formula

Chemical formula

Chemical formula

[0069] In some embodiments, the etching composition comprises (i) each of R 1 , R 2 , and R 3 is

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0070] In some embodiments, the etching composition comprises (i) each of R 1 , R 2 , and R 3each is -OCH3, (ii) the sum of m1 and m2 is 2, (iii) n = 0, (iv) L is [Chemical formula] wherein X 1 , X 2 , and X 3 each is F, and contains the silicon-containing compound of Formula III.

[0071] In some embodiments, the etching composition is such that (i) R 1 , R 2 , and R 3 each is [Chemical formula] wherein (ii) m2 = 3, (iii) n = 1, (iv) A is [Chemical formula] wherein Ra is [Chemical formula] wherein (v) m1 = 0, (vi) L is [Chemical formula] and contains the silicon-containing compound of Formula III.

[0072] In some embodiments, the etching composition is such that (i) R 1 , R 2 , and R 3 each is [Chemical formula] wherein (ii) m2 = 2, (iii) n = 1, (iv) A is [Chemical formula] wherein (v) m1 = 0 and (vi) L is [Chemistry] comprises the silicon-containing compound of formula III as defined below.

[0073] In some embodiments, the etching composition comprises (i) each of R 1 , R 2 , and R 3 is [Chemistry] , (ii) m2 = 3, (iii) n = 1, (iv) A is [Chemistry] , where R a and R b are -CH3, (v) m1 = 3, (vi) L is [Chemistry] comprises the silicon-containing compound of formula III as defined below.

[0074] In some embodiments, the etching composition comprises (i) each of R 1 , R 2 , and R 3 is [Chemistry] , (ii) the sum of m1 and m2 is 2, (iii) n = 0, (iv) L is [Chemistry] comprises the silicon-containing compound of formula III as defined below.

[0075] In some embodiments, the etching composition comprises (i) each of R 1 , R 2 , and R 3 is [Chemistry] and (ii) the sum of m1 and m2 is 3, (iii) n = 0, and (iv) L is [Chemical formula] and includes the silicon-containing compound of Formula III as described above.

[0076] In some embodiments, the etching composition is (i) R 1 , R 2 , and R 3 each of which is [Chemical formula] and (ii) the sum of m1 and m2 is 1, (iii) n = 0, and (iv) L is [Chemical formula] and includes the silicon-containing compound of Formula III as described above.

[0077] In some embodiments, the etching composition has the following structure, namely [Chemical formula] and includes the silicon-containing compound of Formula III having the same, wherein R is [Chemical formula] and x is from 1 to 5. In other aspects of this embodiment, x is 1. In other aspects of this embodiment, x is 2. In other aspects of this embodiment, x is 3. In other aspects of this embodiment, x is 4. In other aspects of this embodiment, x is 5.

[0078] In some embodiments, the one or more silicon-containing compounds include a combination of one or more silicon-containing compounds having Formula I, Formula II, and / or Formula III.

[0079] II. Aqueous solvent

[0080] The etching composition of the present development is aqueous and contains water. In the context of the present disclosure and claims, water functions in various forms, for example, to dissolve one or more components of the composition, as a carrier for those components, as an aid in removing residues, as a viscosity modifier of the composition, and as a diluent. The water used in the etching composition is preferably deionized (DI) water.

[0081] In some embodiments, the aqueous solvent contains water. In other aspects of this embodiment, the aqueous solvent consists essentially of water. In other aspects of this embodiment, the aqueous solvent consists of water.

[0082] Water is included in an amount within a range having a starting point and an ending point selected from the following list of mass percentages, namely, in the range of about 1 mass% to about 50 mass% of the etching composition. Other preferred embodiments of the present disclosure and claims contain about 5.0 mass% to about 35 mass% or 10 mass% to 30 mass% of water. Water may be present in amounts defined by the following list of mass percentages, namely, 1%, 5%, 8%, 10%, 12%, 15%, 17%, 20%, 22%, 25%, 27%, 30%, 32%, 35%, 37%, 40%, 42%, 45%, 47%, and 50%. Still other preferred embodiments of the present disclosure and claims can contain an amount of water such as to achieve the desired mass percentages of these other components.

[0083] Embodiment as an example of an etching composition

[0084] The following are embodiments that are examples of etching compositions comprising (A) pure phosphoric acid and (B) a mixture of (I) a silicon-containing compound disclosed herein and (II) an aqueous solvent.

[0085] In one embodiment, the etching composition is (A) up to about 70 mass% of pure phosphoric acid, (B) a mixture of at least about 30 mass%, and (I) Formula I, namely, [Chemistry] a compound of formula: (i) m = 0 to 20, (ii) each of R 1 , R 2 , R 3 , R 4 , and R 5 is independently hydrogen, a C1-C 10 linear alkyl group, a fluorine-substituted C1-C 10 linear alkyl group, a nitrogen-containing group, an oxygen-containing group, a C3-C 10 branched alkyl group, a C3-C 10 cyclic alkyl group, a C5-C 12 aryl group, a C2-C 10 linear or branched alkenyl group, a C2-C 10 linear or branched alkynyl group, and [Chemistry] selected from the group consisting of, and (iii) each of R a and R b is independently a C1-C 10 linear alkyl group, a C3-C 10 branched alkyl group, a C3-C 10 cyclic alkyl group, a C5-C 12 aryl group, a C2-C 10 linear or branched alkenyl group, a C2-C 10 linear or branched alkynyl group, [Chemistry] and [Chemistry] substituted C1-C 10 alkyl selected from the group consisting of said compound, and (II) said mixture containing an aqueous solvent is included. In other aspects of this embodiment, the etching composition consists essentially of A and B. In other aspects of this embodiment, the etching composition consists of A and B.

[0086] In one embodiment, the etching composition comprises (A) phosphoric acid in an amount of about 70% by mass or less, (B) a mixture in an amount of about 30% by mass or more, (I) Formula II, that is,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0087] In one embodiment, the etching composition is, (A) pure phosphoric acid of about 70% by mass or less, (B) a mixture of about 30% by mass or more, (I) Formula III, that is, [Chemical formula] a compound of, wherein, (i) m1 and m2 are each equal to 0 to 10 on the condition that at least one of m1 and m2 is 1 or more, (ii) n = 0 or 1, (iii) R 1 , R 2 , and R 3 each are independently hydrogen, a C1-C6 linear alkyl group, a C3-C6 branched alkyl group, and [Chemical formula] selected from the group consisting of (iv) A is (a)

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chem.

Chem.

Chem.

Chem.

[0088] In one embodiment, the etching composition is, (A) more than about 70% by mass of pure phosphoric acid, (B) a mixture of less than about 30% by mass, which is (I) Formula I, that is,

Chem.

[0089] In one embodiment, the etching composition is (A) more than about 70% by mass of pure phosphoric acid, (B) less than about 30% by mass of a mixture, wherein (I) Formula II, that is, [Chemical formula] a compound of, wherein in the formula (i) m = 0 - 20, (ii) n = 0 - 20, (iii) R 3 is hydrogen, C1 - C 10 linear alkyl group, fluorine - substituted C1 - C10 a linear alkyl group, a nitrogen-containing group, an oxygen-containing group, C3-C 10 a branched-chain alkyl group, C3-C 10 a cyclic alkyl group, C5-C 12 an aryl group, C2-C 10 a linear or branched alkenyl group and C2-C 10 a linear or branched alkynyl group,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0090] In one embodiment, the etching composition is (A) more than about 70% by mass of pure phosphoric acid, (B) a mixture of less than about 30% by mass, wherein (I) Formula III, that is,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0091] C. Other Components

[0092] The etching composition containing the etching composition exemplified above can contain other components as described below.

[0093] I. Additional Acids

[0094] In some embodiments, the mixture further contains at least one additional acid other than phosphoric acid. In one aspect of this embodiment, the at least one additional acid is one of nitric acid (HNO3), sulfuric acid (H2SO4), hydrochloric acid (HCl), and sulfonic acid (e.g., methanesulfonic acid (CH3SO3H)).

[0095] (a) Sulfuric Acid

[0096] In some embodiments, the at least one additional acid contained in the mixture is sulfuric acid. In one aspect of this embodiment, the at least one additional acid contains about 25% by mass or less of pure sulfuric acid. In other aspects of this embodiment, the at least one additional acid consists of sulfuric acid. In some embodiments, the at least one additional acid consists of about 25% by mass or less of pure sulfuric acid.

[0097] In some embodiments of the etching composition, the mixture contains pure sulfuric acid, and the total content of the pure phosphoric acid and the pure sulfuric acid is between about 80% by mass and about 85% by mass of the composition. In other aspects of this embodiment, the total content of the pure phosphoric acid and the pure sulfuric acid is about 83.5% by mass of the composition.

[0098] In some embodiments of the etching composition, the mixture further comprises pure sulfuric acid, and there is about 2.0 parts by mass to about 7.0 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.0 parts by mass to about 6.0 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.0 parts by mass to about 5.0 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.0 parts by mass to about 4.0 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.0 parts by mass to about 3.0 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.0 parts by mass to about 2.5 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 3.0 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.25 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.5 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid. In other aspects of this embodiment, there is about 2.75 parts by mass of pure phosphoric acid per 1 part by mass of pure sulfuric acid.

[0099] In some embodiments of the etching composition, the mixture further comprises pure sulfuric acid, and the total content of the pure phosphoric acid and the pure sulfuric acid is between about 80% by mass and about 85% by mass of the composition. In other aspects of this embodiment, the total content of the pure phosphoric acid and the pure sulfuric acid is about 83.5% by mass of the composition.

[0100] Various non-limiting embodiments of the etching composition containing sulfuric acid are illustrated below.

[0101] (i) An embodiment that is an example of a composition containing a silicon-containing compound of Formula I and sulfuric acid

[0102] In some embodiments of the etching composition, (i) the compound of Formula I is

Chemical formula

[0103] In some embodiments of the etching composition, (i) the compound of formula I is

Chemical formula

[0104] In some embodiments of the etching composition, (i) the compound of formula I is

Chemical formula

[0105] In some embodiments of the etching composition, (i) the compound of formula I is

Chemical formula

[0106] In some embodiments of the etching composition, (i) the compound of formula I is

Chemical formula

[0107] In some embodiments of the etching composition, (i) the compound of formula I is

Chemical formula

[0108] In some embodiments of the etching composition, (i) the compound of Formula I is

Chemical formula

[0109] In some embodiments of the etching composition, (i) the compound of Formula I is

Chemical formula

[0110] In some embodiments of the etching composition, (i) the compound of Formula I is

Chemical formula

[0111] In some embodiments of the etching composition, (i) the compound of Formula I is

Chemical formula

[0112] In some embodiments, the etching composition comprises (A) up to about 60% by mass of pure phosphoric acid and (B) (i) up to about 5% by mass of

Chemical formula

[0113] In some embodiments, the etching composition comprises (A) pure phosphoric acid of about 60% by mass or less and (B) (i) about 5% by mass or less of

Chemical formula

[0114] In some embodiments, the etching composition comprises (A) pure phosphoric acid of about 60% by mass or less and (B) (i) about 5% by mass or less of

Chemical formula

[0115] Embodiments that are examples of compositions containing a silicon-containing compound of formula II and sulfuric acid

[0116] In some embodiments of the etching composition, (i) the compound of formula II is

Chemical formula

[0117] In some embodiments of the etching composition, (i) the compound of formula II is

Chemical formula

[0118] In some embodiments of the etching composition, (i) the compound of Formula II is

Chem.

[0119] In some embodiments of the etching composition, (i) the compound of Formula II is

Chem.

[0120] In some embodiments of the etching composition, (i) the compound of Formula II is

Chem.

[0121] In some embodiments of the etching composition, (i) the compound of Formula II is

Chem.

[0122] (iii) Embodiments that are examples of compositions comprising a silicon-containing compound of Formula III and sulfuric acid

[0123] In some embodiments of the etching composition, (i) the compound of Formula III is

Chem.

Chem.

[0124] In some embodiments of the etching composition, (i) the compound of formula III is

Chem.

Chem.

[0125] In some embodiments of the etching composition, (i) the compound of formula III is

Chem.

Chem.

[0126] In some embodiments of the etching composition, (i) the compound of Formula III is Si(OCH3)3(CH2CH2CF3), and (ii) the mixture further contains pure sulfuric acid.

[0127] In some embodiments of the etching composition, (i) the compound of Formula III is Si(OCH3)3(CH2CH2CF3), (ii) the mixture further contains pure sulfuric acid, and (iii) the total content of the pure phosphoric acid and the pure sulfuric acid is between about 80% and about 85% by mass of the composition.

[0128] In some embodiments of the etching composition, (i) the compound of Formula III is Si(OCH3)3(CH2CH2CF3), (ii) the mixture further contains sulfuric acid, and (iii) the total content of the pure phosphoric acid and the pure sulfuric acid is about 83.5% by mass of the composition.

[0129] In some embodiments of the etching composition, (i) the compound of Formula III is [Chemical formula] and (ii) the mixture further contains pure sulfuric acid.

[0130] In some embodiments of the etching composition, (i) the compound of Formula III is [Chemical formula] and (ii) the mixture further comprises pure sulfuric acid, and (iii) the total content of the pure phosphoric acid and the pure sulfuric acid is between about 80% and about 85% by mass of the composition.

[0131] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0132] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0133] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0134] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0135] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0136] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0137] In some embodiments of the etching composition, (i) the compound of formula III is

Chemical formula

[0138] (b) Sulfonic acid

[0139] In some embodiments, the at least one additional acid contained in the mixture is a sulfonic acid. This sulfonic acid is typically an alkyl sulfonic acid or an aryl sulfonic acid. The sulfonic acid has a general structure of R'-S(O)(O)-OH. In one aspect of this embodiment, R' is a C1-C10 straight-chain alkyl group, a C3-C 10 branched-chain alkyl group, a C3-C 10 cyclic alkyl group, a C5-C 12 aryl group, a C2-C 10 straight-chain or branched-chain alkenyl group, a C2-C 10 straight-chain or branched-chain alkynyl group. In another aspect of this embodiment, R' is a C1-C10 straight-chain alkyl group or a C3-C 10It is selected from branched-chain alkyl groups. In another aspect, the mixture contains one or more sulfonic acids selected from ethanesulfonic acid, 3-hydroxypropane-1-sulfonic acid, 3-amino-1-propanesulfonic acid, sulfoacetic acid, nonafluorobutane-1-sulfonic acid, benzenesulfonic acid, 3-aminobenzenesulfonic acid, p-toluenesulfonic acid monohydrate, and methanesulfonic acid. In one aspect of the present embodiment, the sulfonic acid is methanesulfonic acid (CH3SO3H).

[0140] (c) Other acids

[0141] In some embodiments, the at least one additional acid contained in the mixture is sulfuric acid and one or more of nitric acid (HNO3) and hydrochloric acid (HCl).

[0142] The total amount of this at least one additional acid (such as sulfonic acid and / or sulfuric acid) is about 0.1 wt% to about 60%, about 0.2 wt% to about 40%, or about 0.5 wt% to about 35% of the etching composition. When this at least one additional acid is used, it is preferably contained in the composition at about 1 wt% to about 30%. In alternative embodiments, the total amount of this at least one additional acid is an amount within a range having a starting point and an ending point defined by the following list of weight percentages, namely 0.1%, 0.5%, 0.8%, 1%, 2%, 3%, 4%, 5%, 6%, 7.0%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 27%, 30%, 32%, 35%, 37%, and 40%. These weight percentages are the weight percentage values of "pure" substances.

[0143] In alternative embodiments, the composition of the present disclosure and the subject matter of the present claims does not contain or substantially does not contain this at least one additional acid (such as the addition of sulfuric acid and / or sulfonic acid).

[0144] II. Additional silicon-containing compounds

[0145] In some embodiments, the mixture can include additional silicon-containing compounds other than the compounds of Formula I, Formula II, or Formula III. Such additional silicon-containing compounds can be one or more of alkylsilsesquioxanes, vinylsilsesquioxane, carboxylic acid alkylsilsesquioxane, and alkylene glycol alkylsilsesquioxane.

[0146] III. Hydroxyl Group-Containing Water-Miscible Solvents

[0147] In some embodiments, the mixture can include a hydroxyl group-containing water-miscible solvent. This hydroxyl group-containing water-miscible solvent mainly functions to protect silicon oxide so that silicon nitride is preferentially and selectively etched.

[0148] Suitable classifications of hydroxyl group-containing water-miscible solvents include, but are not limited to, alkanediols and alkanepolyols (including but not limited to alkylene glycols), glycols, alkoxy alcohols (including but not limited to glycol monoethers), saturated aliphatic monohydric alcohols, unsaturated non-aromatic monohydric alcohols, and ring-containing low molecular weight alcohols.

[0149] (C2-C 20 ) Examples of suitable water-soluble alkanediols and alkanepolyols such as (C2-C 20 ) alkanediols and (C3-C

[0150] ) alkanetriols include, but are not limited to, 2-methyl-1,3-propanediol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 2,3-butanediol, and pinacol. Examples of suitable water-soluble alkylene glycols include, but are not limited to, ethylene glycol, propylene glycol, diethylene glycol, glycerol, dipropylene glycol, triethylene glycol, and tetraethylene glycol.

[0151] Examples of suitable water-soluble alkoxy alcohols include, but are not limited to, 3-methoxy-3-methyl-1-butanol, 3-methoxy-1-butanol, 1-methoxy-2-butanol, and water-soluble glycol monoethers.

[0152] Examples of suitable water-soluble glycol monoethers include, but are not limited to, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, 1-methoxy-2-propanol, 2-methoxy-1-propanol, 1-ethoxy-2-propanol, 2-ethoxy-1-propanol, propylene glycol mono-n-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, and ethylene glycol monobenzyl ether, diethylene glycol monobenzyl ether, and mixtures thereof.

[0153] Examples of suitable water-soluble saturated aliphatic monohydric alcohols include, but are not limited to, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 2-pentanol, t-pentyl alcohol, 1-hexanol, and mixtures thereof.

[0154] Examples of suitable water-soluble unsaturated non-aromatic monohydric alcohols include, but are not limited to, allyl alcohol, propargyl alcohol, 2-butenyl alcohol, 3-butenyl alcohol, 4-penten-2-ol, and mixtures thereof.

[0155] Examples of suitable water-soluble ring-containing low molecular weight alcohols include, but are not limited to, α-terpineol, tetrahydrofurfuryl alcohol, furfuryl alcohol, 1,3-cyclopentanediol, and mixtures thereof.

[0156] In some embodiments, the amount of the hydroxyl group-containing water-miscible solvent constitutes from about 1.0% to about 30% by weight of the composition. When this hydroxyl group-containing water-miscible solvent is used, it is preferably from about 5% to about 15% by weight of the composition.

[0157] In some embodiments, the composition of the present disclosure and the subject of the present claims does not contain or substantially does not contain a hydroxyl group-containing water-miscible solvent, or does not contain or substantially does not contain any or all of the above hydroxyl group-containing water-miscible solvents.

[0158] IV. Silicic acid

[0159] In some embodiments, the mixture can include silicic acid. When silicic acid is used, it aids in protecting silicon oxide and improving the selectivity of silicon nitride etching.

[0160] In some embodiments, the amount of silicic acid constitutes from about 0.001% to about 5.0% by weight of the composition, preferably from about 0.01% to about 2.0% by weight. In other embodiments, this silicic acid constitutes from about 0.02% to about 0.08% by weight of the composition.

[0161] In some embodiments, the composition of the present disclosure and the subject of the present claims is not added with silicic acid or is substantially not added with silicic acid.

[0162] V. Phosphoric acid compounds

[0163] In some embodiments, the mixture can include a phosphoric acid compound, such as triethyl phosphate (TEPO) and / or trimethyl phosphate (TMPO). When a phosphoric acid compound is used, it functions as a supplementary solvent.

[0164] In some embodiments, the amount of the phosphoric acid compound (e.g., TMPO) constitutes about 0.05% to about 15% by mass of the composition, preferably about 0.1% to about 5% by mass. In other embodiments, when a phosphoric acid compound is used, the phosphoric acid compound (e.g., TMPO) constitutes about 2% by mass of the composition.

[0165] In some embodiments, the composition of the present disclosure and the subject matter of the present claims is not added with or is substantially free of a phosphoric acid compound.

[0166] VI. Surfactants

[0167] In some embodiments, the mixture can include at least one water-soluble nonionic surfactant. The surfactant serves to assist in the removal of residues.

[0168] Examples of these water-soluble nonionic surfactants include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene higher alcohol ether, polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene derivatives, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitol tetraoleate, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol distearate, polyethylene glycol monooleate, polyoxyethylene alkylamine, polyoxyethylene hydrogenated castor oil, alkyl alkanolamide, and mixtures thereof.

[0169] In some embodiments, the amount of the surfactant may be about 0.001% to about 5% by weight of the composition, preferably about 0.01% to about 2.5% by weight of the composition, and most preferably about 0.1% to about 1.0% by weight of the composition.

[0170] In some embodiments, the composition of the present disclosure and the subject matter of the present claims may not contain or may be substantially free of a surfactant.

[0171] VII. Chelating Agent

[0172] In some embodiments, the mixture may include at least one metal chelating agent. The metal chelating agent may function to retain the metal in the composition and increase the ability of the composition to enhance the dissolution of metal residues.

[0173] Examples of suitable chelating agents include the following organic acids and their isomers and salts, namely ethylenediaminetetraacetic acid (EDTA), butylenediaminetetraacetic acid, (1,2-cyclohexylenediamine)tetraacetic acid (CyDTA), diethylenetriaminepentaacetic acid (DETPA), ethylenediaminetetrapropionic acid, (hydroxyethyl)ethylenediaminetriacetic acid (HEDTA), N,N,N’,N’-ethylenediaminetetra(methylenephosphonic) acid (EDTMP), triethylenetetraminehexaacetic acid (TTHA), 1,3-diamino-2-hydroxypropane-N,N,N’,N’-tetraacetic acid (DHPTA), methyliminodiacetic acid, propylenediaminetetraacetic acid, nitrilotriacetic acid (NTA), citric acid, tartaric acid, gluconic acid, saccharic acid, glyceric acid, oxalic acid, phthalic acid, maleic acid, mandelic acid, malonic acid, lactic acid, salicylic acid, propyl gallate, pyrogallol, 8-hydroxyquinoline, and cysteine, but are not limited thereto. Preferred chelating agents are aminocarboxylic acids such as EDTA and CyDTA and aminophosphonic acids such as EDTMP.

[0174] In some embodiments, the amount of the chelating agent constitutes from about 0.1% to about 10% by weight of the composition, preferably from about 0.5% to about 5% by weight.

[0175] In some embodiments, the composition of the present disclosure and the subject matter of the present claims does not contain or substantially does not contain a chelating agent.

[0176] In certain embodiments, the composition substantially does not contain or does not contain metal hydroxides, addition of metals, halide-containing compounds, TEOS, silyl phosphate compounds, and silanes and silanols that do not contain repeating monomers.

[0177] Manufacturing method

[0178] The subject matter of the present disclosure and the present claims further includes a method for manufacturing the etching composition described and claimed herein.

[0179] In one embodiment, the method for forming the etching composition is, (A) Phosphoric acid pure of about 70% by mass or less, and (B) A mixture of about 30% by mass or more, (I) Formula I, namely,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0180] In one embodiment, the method for forming the etching composition is (A) phosphoric acid of about 70% by mass or less, (B) a mixture of about 30% by mass or more, and (I) Formula II, that is,

Chemical formula

Chemical formula

Chemical formula

[0181] In one embodiment, the method for forming the etching composition is (A) pure phosphoric acid of about 70% by mass or less, (B) a mixture of about 30% by mass or more, which is (I) Formula III, that is, [Chem.] a compound of, wherein (i) at least one of m1 and m2 is 1 or more, provided that m1 and m2 are each equal to 0 - 10, (ii) n = 0 or 1, (iii) each of R 1 , R 2 , and R 3 is independently hydrogen, a C1 - C6 straight-chain alkyl group, a C3 - C6 branched-chain alkyl group, and [Chemical formula] selected from the group consisting of (iv) A is (a) [Chemical formula] (b) R a is selected from hydrogen, a C1-C6 straight-chain alkyl group, or a C3-C6 branched-chain alkyl group [Chemical formula] (c) R a and R b are each independently selected from hydrogen, a C1-C6 straight-chain alkyl group, or a C3-C6 branched-chain alkyl group [Chemical formula] (d) [Chemical formula] selected from (v) L is (a) [Chemical formula] (b) [Chemical formula] (c) [Chemical formula] (d) [Chemical formula] (e) X 1 、X 2 、and X 3 each is independently selected from Cl, Br, F, or I [Chemical formula] (f) [Chemical formula] (g) [Chemical formula] (h) [Chemical formula] (i) [Chemical formula] (j) [Chemical formula] the compound selected from, and (II) the mixture containing an aqueous solvent including mixing them.

[0182] In one embodiment, the method for forming the etching composition is (A) pure phosphoric acid of more than about 70% by mass, (B) a mixture of less than about 30% by mass, (I) Formula I, that is, [Chemical formula] a compound of, wherein (i) m = 0 to 20, (ii) R 1 , R 2 , R 3 , R 4 , and R 5 each of which is independently hydrogen, C1 - C 10 linear alkyl group, fluorine-substituted C1 - C 10 linear alkyl group, nitrogen-containing group, oxygen-containing group, C3 - C 10 branched-chain alkyl group, C3 - C 10 cyclic alkyl group, C5 - C 12 aryl group, C2 - C 10 linear or branched alkenyl group, C2 - C 10 linear or branched alkynyl group, and [Chemical formula] selected from the group consisting of, and (iii) R a and R b each independently is a C1 - C 10 linear alkyl group, a C3 - C 10 branched alkyl group, a C3 - C 10 cyclic alkyl group, a C5 - C 12 aryl group, a C2 - C 10 linear or branched alkenyl group, a C2 - C 10 linear or branched alkynyl group,

Chemical formula

Chemical formula

[0183] In one embodiment, the said method for forming the etching composition is (A) more than about 70% by mass of pure phosphoric acid, (B) a mixture of less than about 30% by mass, where (I) Formula II, that is,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0184] In one embodiment, the method for forming the etching composition is (A) more than about 70% by mass of pure phosphoric acid, (B) a mixture of less than about 30% by mass, (I) Formula III, that is,

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0185] Method of Use

[0186] The subject matter of the present disclosure and claims further includes a method for selectively improving the etching rate of silicon nitride compared to silicon dioxide on a composite semiconductor device containing silicon nitride and silicon dioxide.

[0187] In one embodiment, the method comprises: (a) contacting the composite semiconductor device comprising silicon nitride and silicon dioxide with one or more of the etching compositions disclosed and / or claimed herein; and (b) cleaning the composite semiconductor device after at least partially removing the silicon nitride. In other aspects of this embodiment, the contacting step is carried out at a temperature of about 160°C.

[0188] In other embodiments, the method can include (c) a drying step.

[0189] In the methods of this description, "at least partially removed" means removal of at least 90%, preferably at least 95% of the material. Most preferably, at least 99% is removed using the compositions of this development.

[0190] In other embodiments, the method can include a pretreatment step that includes contacting the substrate with dilute hydrofluoric acid (dHF) (a 1:100 HF / water mixture) (e.g., by immersion or spraying). The dHF pretreatment step can also be omitted, and it has been found that high relative etching rates can still be achieved using the compositions of this disclosure and claims. Also, when this dHF pretreatment step is used, it has been found that the compositions of this disclosure and claims cause less damage to the substrate compared to when using a phosphoric acid composition alone. The spread of damage caused by this dHF pretreatment step can be minimized by suppressing agitation when treating with the compositions of this disclosure and claims and shortening the time between the pretreatment and contact with the compositions of this disclosure and claims.

[0191] In some embodiments, the contacting step can be carried out by any suitable means, such as, for example, immersion, spraying, or via a single-wafer process.

[0192] In some embodiments, the temperature of the composition during the contacting step is preferably about 100°C to 200°C. In other embodiments, this temperature is about 140°C to 180°C. In other embodiments, the temperature of the composition during the contacting step is about 160°C.

[0193] In some embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 300 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 500 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 1000 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 1250 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 1500 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 2000 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 2500 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 3000 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 3500 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 4000 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 4500 or more. In other embodiments, the etching selectivity for selecting silicon nitride over silicon oxide of the etching composition of the present disclosure and the present claims is about 5000 or more.

[0194] In some embodiments, the etching of silicon oxide is less than 1 Å / min. In other aspects, the etching of silicon oxide is less than 0.5 Å / min. In other aspects, the etching of silicon oxide is less than 0.01 Å / min.

[0195] In some embodiments, the cleaning step (c) is carried out by any suitable means, for example, by cleaning the substrate with deionized water by immersion or spraying methods. In another aspect, the cleaning step is carried out using a mixture of deionized water and a water-miscible organic solvent such as isopropyl alcohol.

[0196] In some embodiments, the drying step is carried out by any suitable means, for example, by isopropyl alcohol (IPA) vapor drying, heating, or centrifugal force.

Examples

[0197] Reference is now made to more specific embodiments of the present disclosure and experimental results supporting such embodiments. These examples are presented below to more fully illustrate the content of the present disclosure and should not be construed as in any way limiting the content of the present disclosure.

[0198] It will be apparent to those skilled in the art that various modifications and variations can be made to the content of the present disclosure and the specific examples presented herein without departing from the spirit or scope of the content of the present disclosure. Accordingly, the content of the present disclosure, including the descriptions provided by the following examples, is intended to cover modifications and variations of the content of the present disclosure that fall within the scope of any claims and their equivalents.

[0199] Materials and Methods

[0200] All components used herein are commercially available.

[0201] In this example, the following silicon-containing compounds were applied.

Table 1

[0202] General procedure for preparing the etching composition

[0203] All compositions shown in this example were prepared by mixing the components in a 250 mL beaker using a 1-inch (about 2.54 cm) Teflon-coated stir bar. Typically, the first material added to this beaker was deionized (DI) water. Phosphoric acid was then typically added, followed by the silicon-containing compound, and then (if any) the remaining components.

[0204] Composition of the substrate

[0205] Each 20 mm × 20 mm coupon used in this example included a layer of silicon nitride, i.e., SiN x on a silicon substrate. The comparative example included a layer of silicon oxide, i.e., SiO x on a silicon substrate.

[0206] Processing conditions

[0207] A 1 / 2-inch (about 1.27 cm) spherical Teflon stir bar was set at 300 rpm and an etching test was performed using 100 g of the etching composition in a 250 mL beaker. The etching composition was heated on a hot plate to a temperature of about 160 °C. Prior to the test, the SiNx substrate pieces, polysilicon substrate pieces, and pattern inspection substrate pieces (test coupons) were treated with DHF (1:100 HF / DI water) for about 3 minutes. The SiOx test coupons were not pretreated with DHF. These test coupons were immersed in the composition with stirring for about 3 minutes (SiNx substrate) to about 60 minutes (SiOx substrate).

[0208] These parts were washed in a DI water bath or by spraying DI water for about 3 minutes, and then dried using filtered nitrogen. The etching rates of silicon nitride and silicon oxide were estimated from the changes in thickness before and after etching and measured by spectroscopic ellipsometry (FilmTek™ 2000 PAR-SE, Scientific Computing International). A typical initial layer thickness was 4395 Å for SiN x and 229 Å for SiO x .

[0209] The following series of tables show the evaluation results of some embodiments of the etching compositions of the present disclosure and the present claims. [Table 2] [Table 3]

[0210] Tables 1 and 2 show that the addition of the silicon-containing oligomer suppressed the etching rate of SiO x and increased the selectivity for etching SiN x over SiO2. Table 1 further shows that the addition of sulfuric acid further decreased the SiO2 etching rate and thus increased the selectivity. [Table 4]

[0211] Table 3 further shows a significant effect of sulfuric acid concentration on the selectivity for SiNx over SiO2. [Table 5]

[0212] Table 4 shows that as the concentration of Si compound 1 increases, the SiO2 etching rate decreases, and the selectivity for SiNx over SiO2 clearly increases.

Table 6

Table 7

[0213] Tables 5 and 6 show that methanesulfonic acid plays the same role as sulfuric acid, and the addition of methanesulfonic acid can also reduce the SiO2 etching rate and increase the selectivity.

Table 8

[0214] Table 7 shows the increase in the relative removal rate when the alkylsulfonic acid and sulfuric acid are added to the composition of the present disclosure and claims.

Table 9

Table 10

[0215] The foregoing descriptions have been mainly for illustrative purposes. Although the present disclosure and claims have been shown and described with respect to exemplary embodiments thereof, those skilled in the art should understand that various changes, omissions, and additions to the present disclosure and claims, as well as other various changes, omissions, and additions, can be made to the present disclosure and claims without departing from the spirit and scope of the present disclosure and claims. The present invention includes the following aspects. (1) (A) Pure phosphoric acid of about 70% by mass or less, (B) A mixture of about 30% by mass or more, which (I) Formula I, that is,

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Claims

1. (A) Pure phosphoric acid in an amount exceeding 70×(0.95) mass%, (B) A mixture in an amount less than 30×(1.05) mass%, (I) Formula I, that is, 【Chemical Formula 1】 a compound of, wherein in the formula, (i) m = 0 to 20, (ii) Each of R １ , R ２ , R ３ , R ４ , and R ５ is independently hydrogen, C １ - C １０ linear alkyl group, fluorine-substituted C １ - C １０ linear alkyl group, nitrogen-containing group, oxygen-containing group, C ３ - C １０ branched-chain alkyl group, C ３ - C １０ cyclic alkyl group, C ５ - C １２ aryl group, C ２ - C １０ linear or branched alkenyl group, C ２ - C １０ linear or branched alkynyl group, and 【Chemical Formula 2】 is selected from the group consisting of, and (iii) Each of R ａ and R ｂ is independently C １ - C １０ linear alkylene group, C ３ - C １０ branched-chain alkylene group, C ３ - C １０ cyclic alkylene group, C ５ - C １２ arylene group, C ２ - C １０ linear or branched alkenylene group, C ２ - C １０ linear or branched alkynylene group, 【Chemical Formula 3】 and [Chemical Formula 4] C substituted with １ ~ C １０ The compound selected from the alkylene, or (II) A compound of formula II, [Chemical Formula 5] In the formula, (i) m = 0 to 20, (ii) n = 0 to 20, (iii) R ３ is hydrogen, C １ ~ C １０ linear alkyl group, fluorine-substituted C １ ~ C １０ linear alkyl group, nitrogen-containing group, oxygen-containing group, C ３ ~ C １０ branched alkyl group, C ３ ~ C １０ cyclic alkyl group, C ５ ~ C １２ aryl group, C ２ ~ C １０ linear or branched alkenyl group and C ２ ~ C １０ linear or branched alkynyl group, [Chemical Formula 6] Z １ and Z ２ selected from the group consisting of, and (iv) Each of R ａ and R ｂ is independently C １ ~ C １０ linear alkylene group, C ３ ~ C １０ branched alkylene group, C ３ ~ C １０ cyclic alkylene group, C ５ ~ C １２ arylene group, C ２ ~ C １０ linear or branched alkenylene group, C ２ ~ C １０ linear or branched alkynylene group, [Chemical Formula 7] and 【Chemical Formula 8】 C substituted with １ ~ C １０ selected from alkylene, (v) Z １ and Z ２ are each independently (a) 【Chemical Formula 9】 (b) 【Chemical Formula 10】 (c) 【Chemical Formula 11】 and (d) 【Chemical Formula 12】 at least one compound of formula II selected from, and (III) an aqueous solvent, said mixture containing An etching composition containing, having an etching selectivity of silicon nitride to silicon oxide of 300 or more.

2. said mixture further contains at least one additional acid other than pure phosphoric acid selected from HNO ３ , H ２ SO ４ , HCl, and methanesulfonic acid, the etching composition according to claim 1.

3. (i) the etching composition contains more than 75 × (0.95) mass% of pure phosphoric acid and (ii) less than 25 × (1.05) mass% of said mixture, the etching composition according to claim 1.

4. said mixture further contains one or more additional silicon-containing compounds selected from alkylsilsesquioxanes, vinylsilsesquioxane, carboxylic acid alkylsilsesquioxane, and alkylene glycol alkylsilsesquioxane, the etching composition according to claim 1.

5. The etching composition according to claim 1, wherein the mixture contains a compound of formula I.

6. The etching composition according to claim 1, wherein the mixture contains the compound of formula II.

7. The etching composition according to claim 1, wherein m in one or both of formula I and formula II is 0.

8. The etching composition according to claim 1, wherein the content of the compound of formula I is 5×(1.05) mass% or less.

9. The etching composition according to claim 1, wherein the content of the compound of formula II is 5×(1.05) mass% or less.

10. Containing a compound of formula I, (i) the compound of formula I is 【Chemical Formula 13】 The etching composition according to claim 1.

11. Containing a compound of formula I, (i) the compound of formula I is 【Chemical Formula 14】 and, (ii) the content of the pure phosphoric acid is more than 75×(0.95) mass% of the etching composition, The etching composition according to claim 1.

12. Containing a compound of formula I, (i) the compound of formula I is 【Chemical Formula 15】 The etching composition according to claim 1.

13. Containing a compound of formula I, (i) the compound of formula I is 【Chemical Formula 16】 and, (ii) the content of the pure phosphoric acid is more than 75×(0.95) mass% of the etching composition, The etching composition according to claim 1.

14. comprising a compound of formula II, (i) said compound of formula II is 【Chemical Formula 17】 comprising the etching composition according to claim 1.

15. comprising a compound of formula II, (i) said compound of formula II is 【Chemical Formula 18】 comprising, and (ii) the content of said pure phosphoric acid is in the range of more than 75×(0.95) mass% of the etching composition, the etching composition according to claim 1.

16. comprising a compound of formula II, (i) said compound of formula II is 【Chemical Formula 19】 comprising the etching composition according to claim 1.

17. comprising a compound of formula II, (i) said compound of formula II is 【Chemical Formula 20】 comprising, and (ii) the content of said pure phosphoric acid is more than 75×(0.95) mass% of the etching composition, the etching composition according to claim 1.

18. A method for selectively improving the etching rate of silicon nitride with respect to silicon dioxide on a semiconductor substrate containing silicon nitride and silicon dioxide, (a) contacting the semiconductor substrate containing silicon nitride and silicon dioxide with the etching composition according to claim 1, and (b) washing the semiconductor substrate after at least a part of the silicon nitride is removed. The method including

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