Formulated alkaline chemistry for polysilicon exhume

Abstract

The present invention discloses and claims protection an etching composition capable of selectively removing silicon films while minimizing the etching rate of oxide films, and a method for manufacturing semiconductor devices using the composition.

Description

[Technical Field]

[0001] The subject matter disclosed and claimed in this invention relates to etching compositions, and more particularly to highly selective etching compositions capable of selectively removing silicon films while minimizing the etching rate of oxide films, and a method of manufacturing semiconductors, comprising an etching process using the etching composition. [Previous Technology]

[0002] As semiconductor devices become more highly integrated, their reliability and electrical characteristics are more susceptible to damage or deformation of the layers constituting the semiconductor device. Therefore, when performing an etching process to selectively remove specific material layers using an etchant, it is desirable for the etchant to have higher etch selectivity relative to other material layers and for the etching process to produce fewer byproducts to reduce process defects.

[0003] In the fabrication of 3D NAND flash memory devices, as the number of nitride / oxide substitution layers increases, high aspect ratio (HAR) channel etching challenges the physical limits of current plasma etching technology. To overcome these challenges, the process flow has shifted from single stacks to multiple stacks (e.g., two stacks of 64 layers to provide an equivalent 128-layer array). Figure 1 illustrates a dual-stack process. After HAR channel etching in stack 1, the vertical channels are filled with sacrificial material. Stack 2 is performed on top of stack 1, i.e., nitride / oxide deposition and channel etching. Finally, the filler material is removed, thus achieving HAR channel etching with two times the number of layers. The subject matter disclosed and claimed in this invention can be used as a wet etchant for removing polysilicon in these processes.

[0004] Wet etchant compositions for eliminating pyramidal silicon etch residues produced after etching processes with high silicon-to-silicon oxide selectivity are known. For example, U.S. Patent Application Publication No. 2017 / 0145311 describes an etchant composition that can selectively etch certain crystal planes or perform orientation-selective wet etching and provides a flat bottom. U.S. Patent Application Publication No. 2020 / 0157422 describes a variety of oxide inhibitors that can significantly suppress oxide etch rates in alkaline wet chemical etching formulations and exhibit high silicon-to-silicon oxide selectivity.

[0005] Despite the existence of these known materials and such high integration, the material selectivity requirements for selective silicon sacrificial removal in 3D NAND manufacturing have become more critical – to the point that the SiO x layer needs to be effectively kept intact during etching. Therefore, there is a need in the art to further suppress the SiO x etching rate to achieve even higher silicon-to-SiO x selectivity. [Summary of the Invention]

[0006] In one embodiment, the subject matter disclosed and claimed by the present invention provides an etching composition for selectively removing silicon from silicon oxides in a microelectronic device, comprising: A. one or more aqueous solvents; B. one or more alkanolamines; C. one or more quaternary ammonium hydroxides (“QAH”); and D. one or more silicon-containing compounds (also referred to herein as organosilicon compounds).

[0007] The alkanolamines useful in the subject matter disclosed and claimed by this invention comprise one or more alkanol groups and one or more amino groups. The alkanolamines useful in the subject matter disclosed and claimed by this invention have the structure of Formula I: wherein R1, R2 and R3 are each independently selected from: (a) hydrogen, (b1) C1-C20 straight-chain alkyl, (b2) C4-C20 branched alkyl, (b3) C3-C20 cyclic alkyl; (c) unsubstituted C2-C20 alkyl ether; (d) C1-C20 alkanol; (e) C2-C20 alkyl ether substituted with -OH group; and wherein at least one of R1, R2 and R3 must be (d) or (e).

[0008] Alkanolamines having a monoalkyl group may be present in the compositions of the subject matter disclosed and claimed in this invention. Examples of alkanolamines having a monoalkyl group that can be used in combination with alkanolamines having two or more alkanol groups include monoethanolamine (MEA), N-methylethanolamine, N-ethylethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, isopropanolamine, 2-amino-1-propanol, 3-amino-1-propanol, 2-amino-1-butanol, isobutanolamine, 2-amino-2-ethoxypropanol, and 2-amino-2-ethoxyethanol.

[0009] In some specific examples, the silicon-containing compound has formula II: wherein: (i) m = 0 to 20, (ii) R1, R2, R3, R4 and R5 are each independently selected from the group consisting of hydrogen, C1 to C10 linear alkyl, fluorinated C1 to C10 linear alkyl, nitrogen-containing group, oxygen-containing group, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, and –⸾–OH, and (iii) Ra and Rb are each independently selected from the group consisting of C1 to C10 linear alkyl, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C5 to C10 linear or branched alkenyl. 2 to C10 linear or branched alkynyl, –⸾–NH-C1-C10 alkyl, C1-C10 alkyl substituted with –⸾–OH.

[0010] Specific examples of the subject matter disclosed and claimed in this invention may be used alone or in combination with each other.

Implementation Method

[0013] All references cited herein, including publications, patent applications and patents, are incorporated herein by reference to the extent that each reference is individually and specifically indicated as being incorporated herein by reference and fully elaborated herein.

[0014] In the context of describing the subject matter disclosed and claimed by this invention (especially in the context of the appended claims), the use of the terms “a”, “the”, and similar objects shall be construed as encompassing both singular and plural, unless otherwise specified herein or clearly contradicted by the context. Unless otherwise specified, the terms “comprising,” “having,” “including,” and “containing” shall be construed as open-ended terms (i.e., meaning “including, but not limited to,”). Unless otherwise specified herein, the enumeration of numerical ranges herein is intended only as a way of abbreviating the respective individual values ​​falling within those ranges, and each individual value is incorporated herein as if it were separately referenced herein. Unless otherwise specified herein or clearly contradicted by the context, all methods described herein may be performed in any suitable order. Unless otherwise requested, the use of all embodiments or exemplary language (e.g., “for example”) provided herein is intended only to better illustrate the subject matter disclosed and claimed by this invention and does not constitute a limitation on the scope of the subject matter disclosed and claimed by this invention. No language in this specification should be construed as indicating that any unclaimed element is indispensable to the implementation of the subject matter disclosed and claimed in this invention.

[0015] The preferred embodiments of the subject matter disclosed and claimed herein include the best mode known to the inventors for carrying out the subject matter disclosed and claimed herein. Variations of those embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors expect those skilled in the art to employ these variations appropriately, and the inventors wish to practice the subject matter disclosed and claimed herein in ways different from those specifically described herein. Therefore, the subject matter disclosed and claimed herein includes all modifications and equivalents of the subject matter described in the appended claims as permitted by applicable law. Furthermore, unless otherwise indicated herein or clearly contradicted by the context, the subject matter disclosed and claimed herein covers any combination of the foregoing elements in all possible variations.

[0016] The subject matter disclosed and claimed by this invention is generally related to compositions that can be used during the manufacture of microelectronic devices having the material thereon to selectively remove silicon relative to silicon oxide.

[0017] For ease of reference, "microelectronic device" or "semiconductor substrate" refers to semiconductor substrates, flat panel displays, phase-change memory devices, solar panels, and other products (including those containing solar substrates, photovoltaic cells, and microelectromechanical systems (MEMS)) manufactured for use in microelectronic, integrated circuit, 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 on gallium. The solar substrate may be doped or undoped. It should be understood that the term "microelectronic device" is not intended to be limited in any way and includes any substrate that will ultimately become a microelectronic device or microelectronic component. The microelectronic device or semiconductor substrate may include low-k dielectric materials, barrier materials, and metals such as AlCu alloys, W, Ti, TiN, and other materials thereon.

[0018] As defined herein, “low-k dielectric material” refers to any material used as a dielectric material in a layered microelectronic device, wherein the material has a dielectric constant of less than about 3.5. Preferably, the low-k dielectric material includes low-polarity materials such as silicon-containing organic polymers, silicon-containing hybrid organic / inorganic materials, organosilicon glasses (OSG), TEOS, fluorosilicate glasses (FSG), silica and carbon-doped oxide (CDO) glasses. It should be understood that the low-k dielectric material may have different densities and different porosities.

[0019] As defined herein, the term "barrier material" is equivalent to any material used in the art to seal metal wires, such as copper interconnects, to minimize the diffusion of the aforementioned metal, such as copper, into the dielectric material. Preferred barrier layer materials include tantalum, titanium, ruthenium, hafnium, and other refractory metals and their nitrides and silicates.

[0020] "Substantially contains" is defined herein as less than 2% by weight, preferably less than 1% by weight, more preferably less than 0.5% by weight, and most preferably less than 0.1% by weight. "Substantially contains" also includes 0.0% by weight. The word "containing" means 0.0% by weight.

[0021] As used herein, “about” and “approximately” are intended to correspond to within ±5% of the stated value.

[0022] As used herein, “pure” means the amount of undiluted acid or other material as a percentage by weight. For example, 100 g of 85% phosphoric acid contains 85 g of acid and 15 g of diluent.

[0023] In addition to the familiar and understandable representation of covalent bond connection points, the symbol “–⸾–” is also intended to indicate the connection points of covalent bonds.

[0024] In all such compositions, where a particular component of the composition is discussed with reference to a weight percentage range including a zero lower limit, it should be understood that the component may or may not be present in each particular specific instance of the composition, and where present, it may be present at a concentration as low as 0.001 weight percentage based on the total weight of the composition. Note that unless otherwise specified, all percentages of the component are based on the total weight of the composition. Furthermore, unless otherwise specified, all weight percentages are “pure”, meaning that they do not include the aqueous composition present therein when added to the composition. The reference to “at least one” may be replaced by “one or more”. “At least one” and / or “one or more” includes “at least two” or “two or more” and “at least three” and “three or more”, etc.

[0025] The broad practice of the subject matter disclosed and claimed in this invention relates to the above-described etching compositions, which include, or are substantially composed of, components (A), (B), (C), and (D). In some embodiments, the etching composition may include other components. In some specific examples, the etching compositions disclosed herein are formulated to be free of or substantially free of at least one of the following compounds: acids (inorganic and organic), oxidants, hydrogen peroxide and other peroxides, ammonium ions, halide ions (e.g., fluoride ions, chloride ions), inorganic bases, metal-containing chemicals, reducing agents, hydroxylamine, hydroxylamine derivatives, amidoxime compounds, and abrasives.

[0026] In another specific example, the etching composition is substantially composed of (A), (B), (C), and (D) in different concentrations. In this specific example, the combined amount of (A), (B), (C), and (D) is not equal to 100% by weight, and may include other components that do not substantially alter the effectiveness of the etching composition.

[0027] In another specific example, the etching composition comprises (A), (B), (C), and (D) in different concentrations. In this specific example, the combined amount of (A), (B), (C), and (D) is equal to or equal to approximately 100% by weight, but may include other trace amounts and / or minute amounts of impurities present in small quantities that do not substantially alter the effectiveness of the composition. For example, in one specific example, the etching composition may contain 2% by weight or less of impurities. In another specific example, the etching composition may contain 1% by weight or less of impurities. In yet another specific example, the etching composition may contain 0.05% by weight or less of impurities.

[0028] When the compositions described herein are referred to by weight percent, it should be understood that in any case, the weight percent of all components, including non-essential components such as impurities, shall not add up to 100% by weight. In a composition consisting “substantially of” the components, the sum of these components may reach 100% by weight of the composition or may reach less than 100% by weight. When the sum of these components is less than 100% by weight, the composition may include small amounts of non-essential contaminants or impurities. For example, in one specific instance, the etching composition may contain 2% by weight or less of impurities. In another specific instance, the etching composition may contain 1% by weight or less of impurities. In yet another specific instance, the etching composition may contain 0.05% by weight or less of impurities. In other such specific instances, the composition may form at least 90% by weight, more preferably at least 95% by weight, more preferably at least 99% by weight, more preferably at least 99.5% by weight, most preferably at least 99.9% by weight, and may include other components that do not affect the performance of the etching composition. Otherwise, if there are no significant non-essential impurities, it should be understood that the combination of all essential components will essentially add up to 100 by weight.

[0029] Composition

[0030] As described above, the subject matter disclosed and claimed in this invention relates to etching compositions comprising or substantially comprising (A), (B), (C), and (D), or composed thereof. In some embodiments, the etching composition may include other components.

[0031] Component A: Aqueous solvent

[0032] The etching composition developed herein is aqueous and includes water. In the subject matter disclosed and claimed in this invention, water functions in various ways, for example, dissolving one or more components of the composition, acting as a carrier of the components, acting as an aid in removing residues, acting as a viscosity modifier of the composition, and acting as a diluent. Preferably, the water used in the etching composition is deionized (DI) water.

[0033] In some specific examples, the aqueous solvent contains water. In another aspect of this specific example, the aqueous solvent is substantially composed of water. In another aspect of this specific example, the aqueous solvent is composed of water.

[0034] The water content is within a range having a start and end point selected from the following list of weight percentages: about 1% to about 65% by weight of the etching composition. In one specific example, the composition comprises about 1% to about 65% by weight of water. In one specific example, the composition comprises about 5% to about 65% by weight of water. In one specific example, the composition comprises about 10% to about 65% by weight of water. In one specific example, the composition comprises about 15% to about 65% by weight of water. In one specific example, the composition comprises about 20% to about 65% by weight of water. In one specific example, the composition comprises about 25% to about 65% by weight of water. In one specific example, the composition comprises about 30% to about 65% by weight of water. In one specific example, the composition comprises about 35% to about 65% by weight of water. In one specific example, the composition comprises about 40% to about 65% by weight of water. In one specific example, the composition comprises about 45% to about 65% by weight of water.

[0035] In one specific example, the composition comprises about 1% to about 55% by weight of water. In one specific example, the composition comprises about 5% to about 55% by weight of water. In one specific example, the composition comprises about 10% to about 55% by weight of water. In one specific example, the composition comprises about 15% to about 55% by weight of water. In one specific example, the composition comprises about 20% to about 55% by weight of water. In one specific example, the composition comprises about 25% to about 55% by weight of water. In one specific example, the composition comprises about 30% to about 55% by weight of water. In one specific example, the composition comprises about 35% to about 55% by weight of water. In one specific example, the composition comprises about 40% to about 55% by weight of water. In one specific example, the composition comprises about 45% to about 55% by weight of water.

[0036] In one specific example, the composition comprises about 30% by weight of water. In one specific example, the composition comprises about 35% by weight of water. In one specific example, the composition comprises about 40% by weight of water. In one specific example, the composition comprises about 45% by weight of water. In one specific example, the composition comprises about 50% by weight of water. In one specific example, the composition comprises about 51% by weight of water. In one specific example, the composition comprises about 52% by weight of water. In one specific example, the composition comprises about 53% by weight of water. In one specific example, the composition comprises about 54% by weight of water. In one specific example, the composition comprises about 55% by weight of water. In one specific example, the composition comprises about 56% by weight of water. In one specific example, the composition comprises about 57% by weight of water. In one specific example, the composition comprises about 58% by weight of water. In one specific example, the composition comprises about 59% by weight of water. In one specific example, the composition comprises about 60% by weight of water.

[0037] In other specific embodiments, water may be present in amounts defined by the following weight percentage list: 1, 5, 8, 10, 12, 15, 17, 20, 22, 25, 27, 30, 32, 35, 37, 40, 42, 45, 47, 50, 55, 60, 65, 70, and 75. Other preferred embodiments of the subject matter disclosed and claimed in this invention may include a certain amount of water to achieve the desired weight percentage of other components.

[0038] Component B: Alkylamine

[0039] As described above, the compositions disclosed and claimed by the present invention comprise one or more alkanolamines, which comprise one or more alkanol groups and one or more amino groups. The alkanolamines useful in the subject matter disclosed and claimed by the present invention have the structure of Formula I: wherein R1, R2, and R3 are each independently selected from: (a) hydrogen, (b1) C1-C20 straight-chain alkyl, (b2) C4-C20 branched alkyl, (b3) C3-C20 cyclic alkyl; (c) unsubstituted C2-C20 alkyl ether; (d) C1-C20 alkanol; (e) C2-C20 alkyl ether substituted with a -OH group; and wherein at least one of R1, R2, and R3 must be (d) or (e).

[0040] In one specific example, the one or more alkanolamines comprise a mixture of two or more alkanolamines. In another specific example, the one or more alkanolamines comprise a mixture of three or more alkanolamines. In another specific example, the one or more alkanolamines, the two or more alkanolamines, or the three or more alkanolamines comprise one or more alkanolamine-containing ethers. In another specific example, the one or more alkanolamines consist of a mixture of two alkanolamines. In another specific example, the one or more alkanolamines consist of a mixture of three alkanolamines.

[0041] In one specific example, (b1) is a C1-C15 straight-chain alkyl group. In another specific example, (b1) is a C1-C10 straight-chain alkyl group. In another specific example, (b1) is a C1-C7 straight-chain alkyl group. In another specific example, (b1) is a C1-C5 straight-chain alkyl group. In another specific example, (b1) is a C1-C4 straight-chain alkyl group. In another specific example, (b1) is a C1-C3 straight-chain alkyl group. In another specific example, (b1) is a C1-C2 straight-chain alkyl group. In another specific example, (b1) is a C5 straight-chain alkyl group. In another specific example, (b1) is a C4 straight-chain alkyl group. In another specific example, (b1) is a C3 straight-chain alkyl group. In another specific example, (b1) is a C2 straight-chain alkyl group. In another specific example, (b1) is a C1 straight-chain alkyl group.

[0042] In one specific example, (b2) is a C4-C15 branched alkyl group. In another specific example, (b2) is a C4-C10 branched alkyl group. In another specific example, (b2) is a C4-C7 branched alkyl group. In another specific example, (b2) is a C4-C5 branched alkyl group. In another specific example, (b2) is a C8 branched alkyl group. In another specific example, (b2) is a C7 straight-chain alkyl group. In another specific example, (b2) is a C6 straight-chain alkyl group. In another specific example, (b2) is a C5 straight-chain alkyl group. In another specific example, (b2) is a C4 branched alkyl group.

[0043] In one specific example, (b3) is a C3-C15 cyclic alkyl group. In another specific example, (b3) is a C3-C10 cyclic alkyl group. In another specific example, (b3) is a C31-C7 cyclic alkyl group. In another specific example, (b3) is a C3-C5 cyclic alkyl group. In another specific example, (b3) is a C3-C4 cyclic alkyl group. In another specific example, (b3) is a C6 cyclic alkyl group. In another specific example, (b3) is a C5 cyclic alkyl group. In another specific example, (b3) is a C4 cyclic alkyl group. In another specific example, (b3) is a C3 cyclic alkyl group.

[0044] The alkyl ether group (c) includes (i) a C2-C20 straight-chain alkyl group, (ii) a C4-C20 branched alkyl group, and (iii) a C3-C20 cyclic alkyl group, wherein each of the alkyl groups in (i), (ii) and (iii) contains an oxygen atom (attached between carbon atoms). In (i), (ii) and (iii), the total number of carbon atoms is 2 to 20, or 2 to 15, or 2 to 10, or 2 to 7, or 2 to 5, or 2 to 4, or 2 to 3 carbon atoms.

[0045] Alkyl groups (d) include (i) C1-C20 straight-chain alkyl groups, (ii) C4-C20 branched alkyl groups, and (iii) C3-C20 cyclic alkyl groups. In (i), (ii), and (iii), the total number of structurally suitable carbons is 1 to 20, or 2 to 15, or 2 to 10, or 2 to 7, or 2 to 5, or 2 to 4, or 2 to 3 carbons, and additionally has at least one -(R)(R)-OH attached to a carbon in the alkyl group, wherein each R is independently H or an alkyl group (as defined above, having fewer carbons than its associated R1, R2, or R3 group).

[0046] The -OH-substituted alkyl ether group (e) includes (i) C2-C20 straight-chain alkyl, (ii) C4-C20 branched alkyl, and (iii) C3-C20 cyclic alkyl, wherein the alkyl group of (i), (ii) and (iii) contains an oxygen atom (attached between carbons). In (i), (ii) and (iii), the total number of carbons is 2 to 20, or 2 to 15, or 2 to 10, or 2 to 7, or 2 to 5, or 2 to 4, or 2 to 3 carbons, and additionally has at least one -(R)(R)-OH attached to a carbon in the alkyl group, wherein each R is independently H or an alkyl group (as defined above, having fewer carbons than its associated R1, R2 or R3 group).

[0047] Alkanolamines containing (c) or (e) will be referred to as "alkanolamine-containing ethers". Preferred alkanolamine-containing ethers have (e) an additional alkyl ether group having a -OH group. For both (d) and (e), the -(R)(R)-OH attached to the carbon is preferably a capped group, that is, both R groups are H.

[0048] In one specific example, the composition comprises an alkanolamine of formula II, wherein R1 and R2 are hydrogen and R3 is selected from (d) and (e). In another embodiment of this specific example, the alkanolamine is substantially composed of an alkanolamine of formula II, wherein R1 and R2 are hydrogen and R3 is selected from (d) and (e). In another embodiment of this specific example, the alkanolamine is composed of an alkanolamine of formula II, wherein R1 and R2 are hydrogen and R3 is selected from (d) and (e).

[0049] In another specific example, the composition comprises an alkanolamine of formula II, wherein R1 is (a), R2 is (b1), (b2), or (b3), and R3 is selected from (d) and (e). In another embodiment of this specific example, the alkanolamine is substantially composed of an alkanolamine of formula II, wherein R1 is (a), R2 is (b1), (b2), or (b3), and R3 is selected from (d) and (e). In another embodiment of this specific example, the alkanolamine is composed of an alkanolamine of formula II, wherein R1 is (a), R2 is (b1), (b2), or (b3), and R3 is selected from (d) and (e).

[0050] In another specific example, the composition comprises an alkanolamine of formula II, wherein R1 and R2 are the same or different (b1), (b2) or (b3) and R3 is selected from (d) and (e). In another embodiment of this specific example, the alkanolamine is substantially composed of an alkanolamine of formula II, wherein R1 and R2 are the same or different (b1), (b2) or (b3) and R3 is selected from (d) and (e). In another embodiment of this specific example, the alkanolamine is composed of an alkanolamine of formula II, wherein R1 and R2 are the same or different (b1), (b2) or (b3) and R3 is selected from (d) and (e).

[0051] In another specific example, the composition comprises an alkanolamine of formula II, wherein R1, R2, and R3 are all the same or different (d). In another aspect of this specific example, the alkanolamine is substantially composed of an alkanolamine of formula II, wherein R1, R2, and R3 are all the same or different (d). In another aspect of this specific example, the alkanolamine is composed of an alkanolamine of formula II, wherein R1, R2, and R3 are all the same or different (d).

[0052] In another specific example, the composition comprises an alkanolamine of formula II, wherein R1 is selected from (a), (b1), (b2), or (b3) and R2 and R3 are both the same or different (d). In another aspect of this specific example, the alkanolamine is substantially composed of an alkanolamine of formula II, wherein R1 is selected from (a), (b1), (b2), or (b3) and R2 and R3 are both the same or different (d). In another aspect of this specific example, the alkanolamine is composed of an alkanolamine of formula II, wherein R1 is selected from (a), (b1), (b2), or (b3) and R2 and R3 are both the same or different (d).

[0053] In another specific example, the composition comprises an alkanolamine of formula II, wherein R1 is selected from (a), (b1), (b2), or (b3) and R2 and R3 are both the same or different (e). In another embodiment of this specific example, the alkanolamine is substantially composed of an alkanolamine of formula II, wherein R1 is selected from (a), (b1), (b2), or (b3) and R2 and R3 are both the same or different (e). In another embodiment of this specific example, the alkanolamine is composed of an alkanolamine of formula II, wherein R1 is selected from (a), (b1), (b2), or (b3) and R2 and R3 are both the same or different (e).

[0054] As shown in the above structure, in some specific instances, the alkanolamine that can be used in the subject matter disclosed and claimed by this invention includes two or more of the same or different (preferably the same) alkanolic groups. In some specific instances, the alkanolamine includes three or more of the same or different (preferably the same) alkanolic groups.

[0055] Examples of alkanolamines that can be used in the subject matter disclosed and claimed in this invention are preferably miscible with water and include, but are not limited to, monoethanolamine (MEA), aminoethoxyethanol, methanolamine, N-methylethanolamine, N-ethylethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, diethanolamine, triethanolamine (TEA), tert-butyldiethanolamine, isopropanolamine, 2-amino-1-propanol, 3-amino-1-propanol, 2-amino-1-butanol, isobutanolamine, 2-amino-2-ethoxypropanol, 2-amino-2-ethoxyethanol and mixtures thereof.

[0056] Examples of monoethanolamine (MEA), methanolamine, 2-amino-1-propanol, 3-amino-1-propanol, 2-amino-1-butanol, isobutanolamine, and isopropanolamine-based alkanolamines, wherein R1 and R2 are hydrogen and R3 is (d). Examples of N-methylethanolamine, N-ethylethanolamine, N,N-dimethylethanolamine, and N,N-diethylethanolamine, wherein R1 and R2 are H or b1 or b2, and R3 is (d). Examples of aminoethoxyethanol, 2-amino-2-ethoxypropanol, and 2-amino-2-ethoxyethanol-based alkanolamines, wherein R1 and R2 are hydrogen and R3 is (e). N-methyldiethanolamine, N-ethyldiethanolamine, diethanolamine, triethanolamine (TEA), and tert-butyldiethanolamine are defined as R1, R2, and / or R3, comprising two or more of the same or different (preferably the same) alkyl groups (d). When R1 and R2 are the same alkyl group, R3 is often selected from hydrogen or straight-chain, branched, or cyclic alkyl groups.

[0057] In one specific example, the one or more alkanolamines include monoethanolamine (MEA). In one specific example, the one or more alkanolamines are substantially composed of monoethanolamine (MEA). In one specific example, the one or more alkanolamines are composed of monoethanolamine (MEA).

[0058] As described above, in some specific examples, a mixture of two or more alkanolamines is used. Therefore, in another aspect of this specific example, the at least one alkanolamine comprises a mixture of two or more alkanolamines. In another aspect of this specific example, the at least one alkanolamine is composed of a mixture of two alkanolamines.

[0059] As described above, in some specific examples, a mixture of three or more alkanolamines is used. Therefore, in another aspect of this specific example, the at least one alkanolamine comprises a mixture of three or more alkanolamines. In another aspect of this specific example, the at least one alkanolamine is composed of a mixture of three alkanolamines.

[0060] In another specific instance, (i) the at least one alkanolamine, (ii) the two or more alkanolamines, or (iii) the three or more alkanolamines include at least one alkanolamine-containing ether.

[0061] In one specific example, (i) the at least monoalkyl alcoholamine, (ii) the at least dialkyl alcoholamine, and (iii) the at least trialkyl alcoholamine are selected from aminoethoxyethanol, 2-amino-2-ethoxypropanol, 2-amino-2-ethoxyethanol and mixtures thereof.

[0062] In another specific example, (i) the at least monoalkylolamine, (ii) the at least dialkylolamine, and (iii) the at least trialkylolamine comprise monoethanolamine, isopropanolamine, and 2-(2-aminoethoxy)ethanol. In another embodiment of this specific example, the at least trialkylolamine is substantially composed of monoethanolamine, which is composed of monoethanolamine, isopropanolamine, and 2-(2-aminoethoxy)ethanol.

[0063] In some specific examples, the mixture of two or more alkanolamines or three or more alkanolamines includes at least one alkanolamine-containing ether and at least one or two alkanolamines, wherein R1 and R2 are hydrogen and R3 is (d).

[0064] In one specific example, the composition comprises about 20% to about 70% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 20% to about 65% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 35% to about 60% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 40% to about 55% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 45% to about 50% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 43% to about 47% by weight of the one or more alkanolamine.

[0065] In one specific example, the composition comprises about 20% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 25% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 30% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 35% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 40% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 41% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 42% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 43% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 44% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 45% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 46% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 47% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 48% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 49% by weight of the one or more alkanolamine. In one specific example, the composition comprises about 50% by weight of the one or more alkanolamine.

[0066] Component C: Quaternary ammonium hydroxide

[0067] As described above, the one or more base components may include one or more quaternary ammonium hydroxides. Suitable quaternary ammonium hydroxides include, but are not limited to, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), ethyltrimethylammonium hydroxide (ETMAH), benzyltrimethylammonium hydroxide (BTMAH), choline hydroxide, tri(hydroxyethyl)methylammonium hydroxide, and dimethyldipropylammonium hydroxide (DMDPAH). In some specific examples, TEAH is preferred. In such specific examples, TEAH is used in an aqueous solution, for example, a 35% by weight aqueous solution. In other specific examples, DMDPAH is preferred. In such specific examples, DMDPAH is used in a 20% by weight solution in propylene glycol. In some specific examples, ETMAH is preferred. In such specific examples, ETMAH is used in an aqueous solution, for example, a 20% by weight aqueous solution. In some specific examples, TMAH is preferred. In such specific instances, the aqueous solution is sampled using TMAH, for example, a 25% by weight aqueous solution. In some specific instances, the solution does not contain TMAH.

[0068] The quaternary ammonium hydroxide may be present in any of the following ranges: from about 0.1% by weight to about 20% by weight, from 1% by weight to about 15% by weight, or from about 1% by weight to about 14% by weight, or from about 1% by weight to about 13% by weight, or from about 1% by weight to about 12% by weight, or from about 1% by weight to about 11% by weight, or from about 1% by weight to about 10% by weight, or from about 1% by weight to about 9% by weight, or from about 1% by weight to about 8% by weight, or from about 1% by weight to about 7% by weight, or from about 1% by weight to about 6% by weight, or from about 1% by weight to about 5% by weight, or from about 1% by weight to about 4% by weight, or from about 1% by weight to about 3% by weight, or from about 1% by weight to about 2% by weight, or from about 0.1% by weight to about 0.9% by weight, or from about 0.4% by weight to about 0.5% by weight, or from about 0.1% by weight to about 0.2% by weight. More preferably, the quaternary ammonium hydroxide is present, but in an amount not exceeding about 20% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 8% to 15% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 8% to about 13% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 10% to about 15% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 0.1% to about 1% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 0.4% to about 2% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 0.4% to about 1% by weight. In some preferred compositions, the quaternary ammonium hydroxide is present in about 0.1% to about 0.5% by weight.

[0069] In one specific example, the solution comprises about 0.5 wt% to 5 wt% of pure TEAH. In another specific example, the solution comprises about 1 wt% to about 4 wt% of pure TEAH. In another specific example, the solution comprises about 1.5 wt% to about 3.5 wt% of pure TEAH. In another specific example, the solution comprises about 2 wt% to about 3 wt% of pure TEAH. In another specific example, the solution comprises about 0.5 wt% of pure TEAH. In another specific example, the solution comprises about 1 wt% of pure TEAH. In another specific example, the solution comprises about 1.5 wt% of pure TEAH. In another specific example, the solution comprises about 2 wt% of pure TEAH. In another specific example, the solution comprises about 2.5 wt% of pure TEAH. In another specific example, the solution comprises about 3 wt% of pure TEAH. In another sample of this specific example, the solution comprises approximately 3.5% by weight of pure TEAH. In another sample of this specific example, the solution comprises approximately 4% by weight of pure TEAH. In another sample of this specific example, the solution comprises approximately 5% by weight of pure TEAH.

[0070] In one specific example, the solution comprises about 1% to 5% by weight of pure DMDPAH. In another specific example, the solution comprises about 1% to about 4.5% by weight of pure DMDPAH. In another specific example, the solution comprises about 1.5% to about 4% by weight of pure DMDPAH. In another specific example, the solution comprises about 2% to about 3.5% by weight of pure DMDPAH. In another specific example, the solution comprises about 2% to about 3% by weight of pure DMDPAH. In another specific example, the solution comprises about 2.1% by weight of pure DMDPAH. In another specific example, the solution comprises about 2.2% by weight of pure DMDPAH. In another specific example, the solution comprises about 2.3% by weight of pure DMDPAH. In another specific example, the solution comprises about 2.4% by weight of pure DMDPAH. In another sample of this specific example, the solution comprises approximately 2.6% by weight of pure DMDPAH. In another sample of this specific example, the solution comprises approximately 2.8% by weight of pure DMDPAH. In another sample of this specific example, the solution comprises approximately 3% by weight of pure DMDPAH.

[0071] In one specific example, the solution comprises about 0.5% to 5% by weight of pure choline hydroxide. In another specific example, the solution comprises about 1% to about 4% by weight of pure choline hydroxide. In another specific example, the solution comprises about 1.5% to about 3.5% by weight of pure choline hydroxide. In another specific example, the solution comprises about 2% to about 3% by weight of pure choline hydroxide. In another specific example, the solution comprises about 0.5% by weight of pure choline hydroxide. In another specific example, the solution comprises about 1% by weight of pure choline hydroxide. In another specific example, the solution comprises about 1.5% by weight of pure choline hydroxide. In another specific example, the solution comprises about 2% by weight of pure choline hydroxide. In another specific example, the solution comprises about 2.5% by weight of pure choline hydroxide. In another specific example, the solution comprises about 3% by weight of pure choline hydroxide. In another sample of this specific example, the solution comprises approximately 3.5% by weight of pure choline hydroxide. In another sample of this specific example, the solution comprises approximately 4% by weight of pure choline hydroxide. In another sample of this specific example, the solution comprises approximately 5% by weight of pure choline hydroxide.

[0072] In one specific example, the solution comprises about 0.1 wt% to about 3 wt% of pure ETMAH. In one specific example, the solution comprises about 0.1 wt% to about 2.5 wt% of pure ETMAH. In one specific example, the solution comprises about 0.1 wt% to about 2 wt% of pure ETMAH. In one specific example, the solution comprises about 0.1 wt% to about 1.5 wt% of pure ETMAH. In one specific example, the solution comprises about 0.1 wt% to about 1 wt% of pure ETMAH. In one specific example, the solution comprises about 0.1 wt% to about 0.5 wt% of pure ETMAH. In one specific example, the solution comprises about 0.2 wt% to about 2 wt% of pure ETMAH. In one specific example, the solution comprises about 0.2 wt% to about 1.5 wt% of pure ETMAH. In one specific example, the solution comprises about 0.2 wt% to about 1 wt% of pure ETMAH. In one specific example, the solution comprises about 0.2 wt% to about 0.5 wt% pure ETMAH. In another specific example, the solution comprises about 0.1 wt% pure ETMAH. In another specific example, the solution comprises about 0.2 wt% pure ETMAH. In another specific example, the solution comprises about 0.3 wt% pure ETMAH. In another specific example, the solution comprises about 0.4 wt% pure ETMAH. In another specific example, the solution comprises about 0.5 wt% pure ETMAH. In another specific example, the solution comprises about 0.6 wt% pure ETMAH. In another specific example, the solution comprises about 0.7 wt% pure ETMAH. In another specific example, the solution comprises about 0.8 wt% pure ETMAH. In another specific example, the solution comprises about 0.9 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.0 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.1 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.2 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.3 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.4 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.5 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.6 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.7 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.8 wt% pure ETMAH. In another sample of this specific example, the solution comprises about 1.9 wt% pure ETMAH.In another sample of this specific example, the solution comprises approximately 2.0% by weight of pure ETMAH.

[0073] In one specific example, the solution comprises about 0.1 wt% to about 3 wt% of pure TMAH. In one specific example, the solution comprises about 0.1 wt% to about 2.5 wt% of pure TMAH. In one specific example, the solution comprises about 0.1 wt% to about 2 wt% of pure TMAH. In one specific example, the solution comprises about 0.1 wt% to about 1.5 wt% of pure TMAH. In one specific example, the solution comprises about 0.1 wt% to about 1 wt% of pure TMAH. In one specific example, the solution comprises about 0.1 wt% to about 0.5 wt% of pure TMAH. In one specific example, the solution comprises about 0.2 wt% to about 2 wt% of pure TMAH. In one specific example, the solution comprises about 0.2 wt% to about 1.5 wt% of pure TMAH. In one specific example, the solution comprises about 0.2 wt% to about 1 wt% of pure TMAH. In one specific example, the solution comprises about 0.2 wt% to about 0.5 wt% pure TMAH. In another specific example, the solution comprises about 0.1 wt% pure TMAH. In another specific example, the solution comprises about 0.2 wt% pure TMAH. In another specific example, the solution comprises about 0.3 wt% pure TMAH. In another specific example, the solution comprises about 0.4 wt% pure TMAH. In another specific example, the solution comprises about 0.5 wt% pure TMAH. In another specific example, the solution comprises about 0.6 wt% pure TMAH. In another specific example, the solution comprises about 0.7 wt% pure TMAH. In another specific example, the solution comprises about 0.8 wt% pure TMAH. In another specific example, the solution comprises about 0.9 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.0 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.1 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.2 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.3 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.4 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.5 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.6 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.7 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.8 wt% pure TMAH. In another sample of this specific example, the solution comprises about 1.9 wt% pure TMAH. In another sample of this specific example, the solution comprises approximately 2.0% by weight of pure TMAH.In another sample of this specific example, the solution comprises approximately 2.1% by weight of pure TMAH. In another sample of this specific example, the solution comprises approximately 2.2% by weight of pure TMAH. In another sample of this specific example, the solution comprises approximately 2.3% by weight of pure TMAH. In another sample of this specific example, the solution comprises approximately 2.4% by weight of pure TMAH. In another sample of this specific example, the solution comprises approximately 2.5% by weight of pure TMAH. In one specific example, the solution substantially does not contain pure TMAH. In one specific example, the solution does not contain pure TMAH.

[0074] Component D: Silicon-containing compound

[0075] As described above, the silicon-containing compound has formula II: wherein: (i) m = 0 to 20, (ii) R1, R2, R3, R4 and R5 are each independently selected from the group consisting of hydrogen, C1 to C10 linear alkyl, fluorinated C1 to C10 linear alkyl, nitrogen-containing group, oxygen-containing group, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, and –⸾–OH, and (iii) Ra and Rb are each independently selected from the group consisting of C1 to C10 linear alkyl, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkenyl. 10. Linear or branched alkynyl, –⸾–NH-C1-C10 alkyl, C1-C10 alkyl substituted with –⸾–OH.

[0076] In some specific examples of etching compositions comprising silicon-containing compounds of Formula I, R1, R2, R3, R4, and R5 are all identical. In another embodiment of this specific example, R1, R2, R3, R4, and R5 are all hydrogen.

[0077] In some specific examples of etching compositions comprising silicon-containing compounds of formula I, at least one of R1, R2, R3, R4 and R5 is not hydrogen.

[0078] In some specific examples of etching compositions comprising silicon-containing compounds of Formula I, m = 0 to 20. In another specific example, m is 0. In another specific example, m is 1. In another specific example, m is 2. In another specific example, m is 3. In another specific example, m is 4. In another specific example, m is 5. In another specific example, m is 6. In another specific example, m is 7. In another specific example, m is 8. In another specific example, m is 9. In another specific example, m is 10. In another specific example, m is 11. In another specific example, m is 12. In another specific example, m is 13. In another specific example, m is 14. In another specific example, m is 15. In another specific example, m is 16. In another state of this specific instance, m is 17. In another state of this specific instance, m is 18. In another state of this specific instance, m is 19. In another state of this specific instance, m is 20.

[0079] In one specific example, the solution comprises about 0.15 wt% to about 2 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.2 wt% to about 1.75 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.25 wt% to about 1.5 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.3 wt% to about 1.25 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.35 wt% to about 1.0 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.4 wt% to about 0.95 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.45 wt% to about 0.9 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.5 wt% to about 0.85 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.55 wt% to about 0.8 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.6 wt% to about 0.75 wt% of one or more silicon-containing compounds of pure formula I.

[0080] In one specific example, the solution comprises about 0.15% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.25% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.325% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.4875% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.5% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.65% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.75% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.8% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 0.9 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.0 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.1 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.2 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.3 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.4 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.5 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.6 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.7 wt% of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.8% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 1.9% by weight of one or more silicon-containing compounds of pure formula I. In one specific example, the solution comprises about 2.0% by weight of one or more silicon-containing compounds of pure formula I.

[0081] In some specific examples, the etching composition comprises a silicon-containing compound of formula I, wherein (i) Ra and Rb are both –⸾–C3H6–⸾–, (ii) R1, R2, R4 and R5 are all –⸾–H, and (iii) m = 0.

[0082] In some specific examples, the etching composition comprises a silicon-containing compound of formula I, wherein (i) Ra and Rb are both –⸾–C3H6–⸾–, (ii) R1, R2, R4 and R5 are all –⸾–H, (iii) m = 0, and (iv) R3 = –⸾–C3H6NH2.

[0083] In some specific examples, the etching composition comprises a silicon-containing compound of formula I, wherein (i) Ra and Rb are both –⸾–NH-C 2H 4–⸾–, (ii) R 1, R 2, R 3, R 4 and R 5 are all –⸾–H, and (iii) m = 0.

[0084] In some specific examples, the etching composition comprises a silicon-containing compound of formula I having the following structure: (hereinafter referred to as "silicon compound 1").

[0085] In one specific example, the solution comprises about 0.15 wt% to about 2.0 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.2 wt% to about 1.75 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.25 wt% to about 1.5 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.3 wt% to about 1.25 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.35 wt% to about 1.0 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.4 wt% to about 0.95 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.05 wt% to about 0.9 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.5 wt% to about 0.85 wt% of pure silicon compound 1. In one specific example, the solution comprises about 0.55 wt% to about 0.8 wt% of pure silicon compound 1. In another specific example, the solution comprises about 0.6 wt% to about 0.75 wt% of pure silicon compound 1.

[0086] In one specific example, the solution comprises about 0.15% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.25% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.325% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.5% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.65% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.75% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.8% by weight of pure silicon compound 1. In one specific example, the solution comprises about 0.9% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.0% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.1% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.2% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.3% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.4% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.5% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.6% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.7% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.8% by weight of pure silicon compound 1. In one specific example, the solution comprises about 1.9% by weight of pure silicon compound 1. In one specific example, the solution comprises about 2.0% by weight of pure silicon compound 1.

[0087] Exemplary specific examples of etching compositions

[0088] The following are exemplary specific examples of etching compositions suitable for selectively removing silicon from silicon oxides in microelectronic devices, including: A. one or more aqueous solvents; B. one or more alkanolamines; C. one or more quaternary ammonium hydroxides; and D. one or more silicon-containing compounds.

[0089] In a specific example, the etching component includes: A. Water; B. One or more alkanolamines of formula I: wherein R1, R2 and R3 are each independently selected from: (a) hydrogen, (b1) C1-C20 straight-chain alkyl, (b2) C4-C20 branched alkyl, (b3) C3-C20 cyclic alkyl; (c) unsubstituted C2-C20 alkyl ether; (d) C1-C20 alkanol; (e) C2-C20 alkyl ether substituted with -OH group, and wherein at least one of R1, R2 and R3 must be (d) or (e); C. One or more quaternary ammonium hydroxide; and D. One or more silicon-containing compounds of formula II: wherein: (i) m = 0 to 20, (ii) R1, R2, R3, R4 and R The five series are each independently selected from the group consisting of hydrogen, C1 to C10 linear alkyl, fluorinated C1 to C10 linear alkyl, nitrogen-containing group, oxygen-containing group, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, and –⸾–OH, and (iii) Ra and Rb series are each independently selected from the group consisting of C1 to C10 linear alkyl, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, –⸾–NH-C1-C10 alkyl, and –⸾–OH substituted C1-C10 alkyl.

[0090] In one specific example, the etching composition comprises: A. water; B. monoethanolamine (MEA); C. ethyltrimethylammonium hydroxide (ETMAH); and D. silicon compound 1.

[0091] In one specific example, the etching composition comprises: A. about 35% to about 60% by weight of water; B. about 20.0% to about 70.0% by weight of monoethanolamine (MEA); C. about 0.1% to about 3% by weight of ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.15% to about 2.0% by weight of pure silicon compound 1.

[0092] Other ingredients

[0093] The etching composition, including those listed above, may include other components as desired, as described below.

[0094] Other silicon-containing compounds

[0095] In some specific instances, the mixture may include other silicon-containing compounds different from those shown in Formula 1. Such other silicon-containing compounds may be one or more of alkyl silsesquioxanes, vinyl silsesquioxanes, carboxylic acid alkyl silsesquioxanes, and pentanediol alkyl silsesquioxanes.

[0096] Water-miscible solvent containing hydroxyl groups

[0097] In some specific instances, the mixture may include a water-miscible solvent containing hydroxyl groups. The water-miscible solvent containing hydroxyl groups primarily serves to protect the silicon oxide, allowing the silicon to be preferentially and selectively etched.

[0098] Suitable categories of water-miscible solvents containing hydroxyl groups include, but are not limited to, alkyl glycols and polyols (including, but not limited to, alkylene glycols), glycols, alkoxy alcohols (including but not limited to glycol monoethers), saturated aliphatic monohydric alcohols, unsaturated nonaromatic monohydric alcohols and low molecular weight alcohols containing cyclic structures.

[0099] Suitable examples of water-soluble alkyldiols and polyols include, but are not limited to, (C2-C20) alkyldiols and (C3-C20) alkyltriols, including, but 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.

[0100] Examples of suitable water-soluble penelandyl glycols include, but are not limited to, ethylene glycol, propylene glycol, diethylene glycol, glycerol, dipropylene glycol, triethylene glycol and tetraethylene glycol.

[0101] 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 ethylene glycol monoethers.

[0102] 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.

[0103] Examples of suitable water-soluble saturated aliphatic monohydric alcohols include, but are not limited to, methanol, ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, tributanol, 2-pentanol, tripentanol, 1-hexanol and mixtures thereof.

[0104] Examples of suitable water-soluble unsaturated non-aromatic monohydric alcohols include, but are not limited to, allyl alcohol, propargyl alcohol, 2-butenol, 3-butenol, 4-penten-2-ol and mixtures thereof.

[0105] Examples of suitable water-soluble low molecular weight alcohols containing cyclic structures include, but are not limited to, α-terpineol, tetrahydrofuran methanol, furan methanol, 1,3-cyclopentanediol and mixtures thereof.

[0106] In some specific examples, the amount of the hydroxyl-containing water-miscible solvent constitutes about 1.0% to about 30% by weight of the composition. Preferably, when used, the hydroxyl-containing water-miscible solvent constitutes about 5% to about 15% by weight of the composition.

[0107] In some specific instances, the composition of the subject matter disclosed and claimed by the present invention will be free of or substantially free of hydroxyl-containing water miscible solvents or any or all of the above-listed hydroxyl-containing water miscible solvents.

[0108] Silicic acid

[0109] In some specific instances, the mixture may include silicic acid. If used, the silicic acid helps protect silicon oxides and improves the selectivity of the silicon etching.

[0110] In some specific examples, the amount of the silica will constitute from about 0.001% by weight to about 5.0% by weight of the composition, and more preferably from about 0.01% by weight to about 2.0% by weight. In other specific examples, the silica will constitute from about 0.02% by weight to about 0.08% by weight of the composition.

[0111] In some specific instances, the composition of the subject matter disclosed and claimed by the present invention will contain no or substantially no added silica.

[0112] Surfactant

[0113] In some specific instances, the mixture may include at least one water-soluble nonionic surfactant. The surfactant is used to help remove residues.

[0114] Examples of the water-soluble nonionic surfactant include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oil ether, polyoxyethylene higher alcohol ether, polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene derivatives, polyoxyethylene dehydrated sorbitol monolaurate, polyoxyethylene dehydrated sorbitol monopalmitate, polyoxyethylene dehydrated sorbitol monostearate, polyoxyethylene dehydrated sorbitol tristearate, polyoxyethylene dehydrated sorbitol monooleate, polyoxyethylene dehydrated sorbitol trioleate, polyoxyethylene dehydrated sorbitol tetraoleate, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol distearate, polyethylene glycol monooleate, polyoxyethylene alkylamine, polyoxyethylene hardened castor oil, alkylalkanolamide, and mixtures thereof.

[0115] In some specific examples, the amount of the surfactant will include about 0.001% by weight to about 5% by weight of the composition, preferably about 0.01% by weight to about 2.5% by weight, and most preferably about 0.1% by weight to about 1.0% by weight of the composition.

[0116] In some specific instances, the composition of the subject matter disclosed and claimed by the present invention will be free of or substantially free of surfactants.

[0117] In some specific instances, the composition is substantially free of or contains no metal hydroxides, added metals, halide-containing compounds, TEOS, methyl methacrylate compounds, and silanes and silanols excluding repeating monomers.

[0118] Manufacturing Method

[0119] The subject matter disclosed and claimed by this invention also includes a method for manufacturing the etching composition described and claimed herein.

[0120] In one specific example, the method of forming the etching composition includes combining: A. one or more aqueous solvents; B. one or more alkanolamines; C. one or more quaternary ammonium hydroxides; and D. one or more silicon-containing compounds.

[0121] In one specific example, the method of forming the etching composition includes combining: A. water; B. one or more alkanolamines of formula I: wherein R1, R2 and R3 are each independently selected from: (a) hydrogen, (b1) C1-C20 straight-chain alkyl, (b2) C4-C20 branched alkyl, (b3) C3-C20 cyclic alkyl; (c) unsubstituted C2-C20 alkyl ether; (d) C1-C20 alkanol; (e) C2-C20 alkyl ether substituted with -OH group, and wherein at least one of R1, R2 and R3 must be (d) or (e); C. one or more quaternary ammonium hydroxide; and D. one or more silicon-containing compounds of formula II: wherein: (i) m = 0 to 20, (ii) R1, R2, R3, R 4 and R5 are each independently selected from the group consisting of hydrogen, C1 to C10 linear alkyl, fluorinated C1 to C10 linear alkyl, nitrogen-containing group, oxygen-containing group, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, and –⸾–OH, and (iii) Ra and Rb are each independently selected from the group consisting of C1 to C10 linear alkyl, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, –⸾–NH-C1-C10 alkyl, and –⸾–OH substituted C1-C10 alkyl.

[0122] In one specific example, the method of forming the etching composition includes combining: A. water; B. monoethanolamine (MEA); C. ethyltrimethylammonium hydroxide (ETMAH); and D. silicon compound 1.

[0123] In one specific example, the method of forming the etching composition includes combining: A. about 35% to about 60% by weight of water; B. about 20.0% to about 70.0% by weight of monoethanolamine (MEA); C. about 0.1% to about 3% by weight of ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.015% to about 0.2% by weight of pure silicon compound 1.

[0124] Instructions for Use

[0125] The subject matter disclosed and claimed by this invention further includes a method for selectively removing silicon films while minimizing the etching rate of oxide films using the etching composition disclosed and claimed by this invention, and a method for manufacturing semiconductors, which includes an etching process using the etching composition disclosed and claimed by this invention.

[0126] In one specific example, the method includes the following steps: a. contacting a composite semiconductor device including a silicon film with one or more etch compositions disclosed and / or claimed herein, and b. rinsing the composite semiconductor device after at least partially removing the silicon film. In another embodiment of this specific example, the contact step is performed at a temperature of about 25°C to about 90°C.

[0127] In another specific instance, the method may include c. a drying step.

[0128] In the method described, "at least partial removal" means removing at least 90% of the material, preferably at least 95%. Most preferably, the composition of the present invention removes at least 99%. "Silicon oxide compatibility" means less than 10% film loss.

[0129] In another specific example, the method may include a pretreatment step comprising contacting the substrate with dilute hydrofluoric acid (“DHF”) (1:100 HF:water) (e.g., by immersion or spraying). Reducing agitation and minimizing the time between pretreatment and contact with the composition of the subject matter disclosed and claimed by this invention when treating with such a composition minimizes further damage caused by the dHF pretreatment step.

[0130] In some specific instances, the contact step may be performed by any suitable means, such as, for example, immersion, spraying or via a single-wafer process.

[0131] In some specific examples, the temperature of the composition during the contact step is preferably from about 25°C to about 90°C. In another example, the temperature is from about 40°C to about 80°C. In yet another example, the temperature of the composition during the contact step is about 75°C.

[0132] In some specific examples, the etching selectivity of the silicon-to-silicon oxide in the etching compositions disclosed and claimed by the present invention is between about 300 and about 5000. In some specific examples, the etching selectivity of the silicon-to-silicon oxide in the etching compositions disclosed and claimed by the present invention is between about 500 and about 4000. In some specific examples, the etching selectivity of the silicon-to-silicon oxide in the etching compositions disclosed and claimed by the present invention is between about 1000 and about 3000. In some specific examples, the etching selectivity of the silicon-to-silicon oxide in the etching compositions disclosed and claimed by the present invention is between about 1000 and about 2000. In some specific examples, the etching selectivity of the silicon-to-silicon oxide in the etching compositions disclosed and claimed by the present invention is between about 1000 and about 1500. In some specific examples, the etching selectivity of the silicon-to-silicon oxide in the etching compositions disclosed and claimed by the present invention is between about 500 and about 1500. In some specific instances, the etching selectivity of the silicon-to-silicon oxide of the etching compositions disclosed and claimed in this invention is between about 500 and about 2000.

[0133] In some specific examples, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 300. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 500. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 1000. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 1250. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 1500. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 2000. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 2500. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 3000. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 3500. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 4000. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 4500. In another embodiment, the etching composition disclosed and claimed by the present invention exhibits an etching selectivity of silicon to silicon oxide exceeding about 5000.

[0134] In some specific instances, the silicon oxide etching is less than 1 Å / min. In another sample, the silicon oxide etching is less than 0.5 Å / min. In yet another sample, the silicon oxide etching is less than 0.01 Å / min.

[0135] In some specific instances, the rinsing step c. is carried out by any suitable method, for example, rinsing the substrate with deionized water by immersion or spraying techniques. In another instance, the rinsing step is carried out using a mixture of deionized water and a water-miscible organic solvent, for example, isopropanol.

[0136] In some specific instances, the drying step is carried out by any suitable method, such as isopropanol (IPA) vapor drying, heating, or centrifugal force. Examples

[0137] More specific examples of the present disclosure and experimental results supporting such specific examples will now be referred to. The embodiments described below are given to illustrate the subject matter of the invention more fully and should not be construed as limiting the subject matter of the invention in any way.

[0138] It will be apparent to those skilled in the art that various modifications and variations can be made to the subject matter disclosed herein and the specific embodiments provided therein without departing from the spirit or scope of the subject matter disclosed herein. Therefore, modifications and variations to the subject matter disclosed herein, including those described by the following embodiments, are contemplated to fall within the scope of any claim and its equivalents.

[0139] Materials and Methods:

[0140] All ingredients used in this article are commercially available.

[0141] In the examples, the following silicon-containing compounds were used: Reference group Material CAS number Silicon compound 1 (32.5% or 45%) -- MEA monoethanolamine 141-43-5 ETMAH (20%) Ethyltrimethylammonium hydroxide 30382-83-3 TMAH (25%) Tetramethylammonium hydroxide 75-59-2 DIW Deionized water 7732-18-5 Fluorosilicic acid (33.5% to 35%) fluorosilicic acid 16961-83-4 NH4OH (29%) NH4OH 1336-21-6

[0142] General procedure for preparing etching compositions

[0143] All compositions described in the examples were prepared by mixing the components in a 250 mL beaker having a 1” Teflon-coated stir bar. Typically, the first material added to the beaker is deionized (DI) water.

[0144] Composition of the substrate

[0145] The test specimens used in the embodiments include 20 mm x 20 mm polycrystalline silicon wafers, α silicon wafers and TEOS oxide wafers.

[0146] Processing conditions

[0147] An etching test was performed using 100 g of etching composition in a 250 mL beaker with a 1” Teflon-coated stir bar. The etching composition was heated on a hot plate to a temperature of approximately 25°C to approximately 90°C. The polycrystalline silicon and patterned test substrate (test specimen) was treated with DHF (1:100 HF:DI water) for approximately 3 minutes before testing. The SiOx test specimen was not pretreated with DHF. The test specimen was immersed in the composition for approximately 1 minute (for silicon substrate) to approximately 90 minutes (for SiOx substrate) while stirring.

[0148] Most fragments were then rinsed in a DI water bath or spray for about 3 minutes, followed by drying with filtered nitrogen. The silicon and silicon oxide etching rate was estimated based on the thickness change before and after etching and measured using a spectroscopic ellipsometry (FilmTek™ 2000 PAR-SE, Scientific Computing International).

[0149] The following series of tables shows the evaluation results of several specific examples of the etching compositions disclosed and claimed in this invention. Unless otherwise specified, all example values ​​are denoted as "pure" values. Furthermore, performance wafer testing was not performed on samples that did not meet the selectivity or etching rate requirements. raw material Raw material testing (by weight %) Example 1 (1:50 NH4OH) Example 2 Example 3 NH4OH 29 0.58 0.58 0.58 DIW 100 99.42 99.095 99.4025 Silicon compound 1 32.5 - 0.325 - fluorosilicic acid 33.5-35 - - 0.0175 Total 100.00 100.00 100.00 temperature 60 60 60 a-Si etching rate (Å / min.) 158.7 166.6 157.9 TEOS etching rate (Å / min.) 0.571 0.113 0.131 a-Si / TEOS selectivity 277.9 1474.3 1205.3 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility Compatible - - Cleaning performance Severe silicon residue - - Table 1: Effects of different silicon oxide inhibitors on NH₄OH

[0150] Table 1 confirms that the etching rate of silicon oxide can be suppressed by adding the silicon-containing compound of Formula II and fluorosilicic acid to the NH4OH solution, while keeping the silicon etching rate at the same level. raw material Raw material testing (by weight %) Example 4 Example 5 Example 6 ETMAH 20 0.4 0.4 0.4 Silicon compound 1 32.5 - 0.325 - fluorosilicic acid 33.5-35 - - 0.0175 DIW 100 99.6 99.275 99.5825 Total 100.00 100.00 100.00 temperature 60 60 60 a-Si etching rate (Å / min.) 329.9 309.1 307.6 TEOS etching rate (Å / min.) 0.923 0.169 0.658 a-Si / TEOS selectivity 357.4 1829.0 467.5 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility - - - Cleaning performance - - - Table 2: Effects of different silicon oxide inhibitors in QAH (ETMAH)

[0151] Table 2 confirms that the etching rate of the silicon oxide can be suppressed by adding the silicon-containing compound of Formula II and fluorosilicic acid to the QAH solution. It can be seen that the silicon-containing compound exhibits better protective capabilities. Furthermore, the silicon etching rate is significantly higher by using QAH as the alkali source, and the same level is maintained when adding the silicon-containing compound and fluorosilicic acid. raw material Raw material testing (by weight %) Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 ETMAH 20 0.25 0.3 0.35 0.4 0.5 0.6 DIW 100 99.425 99.375 99.325 99.275 99.175 99.075 Silicon compound 1 32.5 0.325 0.325 0.325 0.325 0.325 0.325 Total 100.00 100.00 100.00 100.00 100.00 100.00 temperature 60 60 60 60 60 60 a-Si etching rate (Å / min.) 175.3 240.6 286.0 309.1 414.4 440.4 TEOS etching rate (Å / min.) 0.096 0.132 0.157 0.169 0.268 0.427 a-Si / TEOS selectivity 1826.0 1822.7 1821.7 1829.0 1546.3 1031.4 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility - Compatible Compatible Compatible - - Cleaning performance - Some silicon residue Some silicon residue Some silicon residue - - Table 3: Effects of different concentrations of ETMASH

[0152] Table 3 further shows that introducing a higher content of QAH can improve the silicon etching rate, but the selectivity of Si to SiOx becomes lower. raw material Raw material testing (weight%) Example 10 Example 10 Example 10 Example 10 Example 10 ETMAH 20 0.4 0.4 0.4 0.4 0.4 DIW 100 99.275 99.275 99.275 99.275 99.275 Silicon compound 1 32.5 0.325 0.325 0.325 0.325 0.325 Total 100.00 100.00 100.00 100.00 100.00 temperature 60 65 70 75 80 a-Si etching rate (Å / min.) 309.1 364.4 560.2 720.4 947.6 TEOS etching rate (Å / min.) 0.169 0.283 0.500 0.682 1.252 a-Si / TEOS selectivity 1829.0 1287.6 1120.4 1056.3 756.9 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility Compatible - - Compatible - Cleaning performance Some silicon residue - - Slight silicon residue - Table 4: Effects of Temperature

[0153] Table 4 shows the effect of the formulation of Example 10 when used for etching at different temperatures. As can be seen from Table 4, the silicon etching rate can be increased by increasing the processing temperature, but the selectivity of Si for SiOx becomes lower. Furthermore, silicon residues cannot be removed even at such a high etching rate of 75 °C. raw material Raw material testing (weight%) Example 13 Example 10 Example 14 Example 15 ETMAH 20 0.4 0.4 0.4 0.4 DIW 100 99.6 99.275 99.1125 98.95 Silicon compound 1 32.5 - 0.325 0.4875 0.65 Total 100.00 100.00 100.00 100.00 temperature 75 75 75 75 a-Si etching rate (Å / min.) 825.3 720.4 648.6 346.5 TEOS etching rate (Å / min.) 3.327 0.682 0.454 0.241 a-Si / TEOS selectivity 248.1 1056.3 1428.6 1437.8 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility - Compatible Compatible - Cleaning performance - Slight silicon residue Slight silicon residue - Table 5: Evaluation of Silicon Compound 1 at Different Concentrations

[0154] Table 5 shows that the silicon oxide etching rate is high when processed at 75 °C. It can be seen that adding more silicon-containing compounds inhibits the silicon oxide etching rate. raw material Raw material testing (by weight %) Example 14 Example 16 Example 17 Example 18 Example 19 ETMAH 20 0.4 0.4 0.4 0.4 0.4 DIW 100 99.1125 52.6125 39.1125 29.1125 22.6125 Silicon compound 1 32.5 0.4875 0.4875 0.4875 0.4875 0.4875 MEA 100 - 46.50 60.00 70.00 76.50 Total 100.00 100.00 100.00 100.00 100.00 temperature 75 75 75 75 75 a-Si etching rate (Å / min.) 648.6 657.3 674.3 694.3 519.6 TEOS etching rate (Å / min.) 0.454 0.291 0.232 0.012 0.002 a-Si / TEOS selectivity 1428.6 2258.8 2906.5 57858.3 259800.0 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility Compatible Compatible Compatible Compatible Compatible Cleaning performance Slight silicon residue clean clean Something remains on the surface Something remains on the surface Table 6: Different water to solvent (MEA) ratios (QAH = ETMAH)

[0155] Table 6 shows the ability of several formulations disclosed and claimed in this invention to remove silicon residues on patterned structures by introducing different levels of alkanolamines. It should be noted that when the solvent-to-water ratio is too high (e.g., greater than about 2.4; see Example 18), residual material may also remain on the wafer surface. raw material Raw material testing (weight%) Example 16 Example 20 Example 21 ETMAH 20 0.4 0.4 0.4 DIW 100 52.6125 52.95 53.625 Silicon compound 1 32.5 0.4875 0.65 0.975 MEA 100 46.50 46.00 45.00 Total 100.00 100.00 100.00 temperature 75 75 75 a-Si etching rate (Å / min.) 657.3 672.2 656.2 TEOS etching rate (Å / min.) 0.291 0.184 0.116 a-Si / TEOS selectivity 2258.8 3653.3 5656.9 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility Compatible - - Cleaning performance clean - - Table 7: Evaluation of Silicon Compound 1 at Different Concentrations

[0156] Table 7 shows that the etching rate of the silicon oxide can also be suppressed by adding more of the silicon-containing compound while introducing the alkanolamine. raw material Raw material testing (weight%) Example 16 Example 22 Example 23 ETMAH 20 0.4 1.00 2.00 DIW 100 52.6125 52.0125 51.0125 Silicon compound 1 32.5 0.4875 0.4875 0.4875 MEA 100 46.50 46.50 46.50 Total 100.00 100.00 100.00 temperature 75 75 75 a-Si etching rate (Å / min.) 657.3 - - Polycrystalline silicon etching rate (Å / min.) 1296.3 1445.1 1862.1 TEOS membrane loss (Å), 90 min. 0.291 0.874 1.226 a-Si / TEOS selectivity 2258.8 - - Polysilicon / TEOS Selectivity 4454.6 1653.4 1518.8 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility Compatible - - Cleaning performance clean - - Table 8: Evaluation of different concentrations of ETMAH

[0157] Table 8 confirms that the polysilicon etching rate can be increased by increasing the QAH content. raw material Raw material testing (weight%) Example 24 Example 25 Example 26 Example 27 TMAH 25 2.00 2.00 2.00 2.00 DIW 100 52.514 47.514 42.514 37.514 Silicon compound 1 45 0.486 0.486 0.486 0.486 MEA 100 45.00 50.00 55.00 60.00 Total 100.00 100.00 100.00 100.00 temperature 75 75 75 75 Polycrystalline silicon etching rate (Å / min.) 2081.5 2050.4 1709.0 1590.9 TEOS etching rate (Å / min), 90 min. 1.289 0.960 0.670 0.587 Polysilicon / TEOS Selectivity 1614.8 2135.8 2550.7 2710.2 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility - Compatible - Compatible Cleaning performance - clean - Some silicon residue Table 9: Different water to solvent (MEA) ratios (QAH = TMAH)

[0158] Table 9 shows the compositions using TMAH as the QAH. raw material Raw material testing (by weight %) Example 28 TMAH 25 2.375 DIW 100 97.625 Total 100.00 temperature 65 Polycrystalline silicon etching rate (Å / min.) 1923.50 TEOS etching rate (Å / min), 90 min. 1.600 Polysilicon / TEOS Selectivity 1202.2 Performance on patterned wafers (Processing time = 90 min.) SiOx compatibility Compatible Cleaning performance Slight silicon residue Table 10: Effects of 2.38% TMAH (pure)

[0159] Table 10 provides a comparative group formulation using approximately 2.4% by weight of TMAH. It can be seen that the TMAH formulations in Table 9 exhibit superior Si-to-SiOx selectivity and residue removal power compared to compositions containing only TMAH.

[0160] Summary

[0161] The subject matter disclosed and claimed in this invention relates to a semi-aqueous etching composition for polycrystalline silicon mining applications. Compared to conventional alkaline solutions, this formulated chemical substance can completely remove polycrystalline silicon with similar processing time without residue, and no damage to SiOx has been observed. Clearly, the composition disclosed and claimed in this invention includes a silicon oxide inhibitor that suppresses the oxide etching rate and improves the selectivity of Si for SiOx in alkaline chemicals. Furthermore, the cleaning properties of the composition disclosed and claimed in this invention can be "tuned" for specific applications by controlling the ratio of water to solvent.

[0162] The preceding description is primarily for illustrative purposes. Although the subject matter disclosed and claimed in this invention has been shown and described with respect to exemplary specific examples thereof, it should be understood that those skilled in the art may make the foregoing and various other changes, omissions and additions to its format and details without departing from the spirit and scope of the subject matter disclosed and claimed in this invention. [Simplified Explanation of the Diagram]

[0011] The following figures, which are included and constitute a part of this specification to provide a further understanding of the subject matter disclosed in this invention, illustrate specific examples of the subject matter disclosed in this invention and, together with the description, serve to explain the principles of the subject matter disclosed in this invention. In these figures:

[0012] Figure 1 illustrates the 3D NAND process flow of HAR vertical channel etching using dual stacking.

Claims

1. An etching composition comprising: A. 20% to 65% by weight of water; B. one or more alkanolamines of formula I, wherein R1, R2 and R3 are each independently selected from: (a) hydrogen, (b1) C1-C20 straight-chain alkyl, (b2) C4-C20 branched alkyl, (b3) C3-C20 cyclic alkyl; (c) unsubstituted C2-C20 alkyl ether; (d) C1-C20 alkanol; (e) -OH-substituted C2-C20 alkyl ether, wherein at least one of R1, R2 and R3 is necessarily (d) or (e); C. 0.1% to 3% by weight of one or more quaternary ammonium hydroxides; and D. 0.15% to 2.0% by weight of pure one or more silicon-containing compounds of formula II, wherein: (i) m = 0 to 20, (ii) R1, R2, R3, R4 and R5 are each independently selected from the group consisting of hydrogen, C1 to C10 linear alkyl, fluorinated C1 to C10 linear alkyl, nitrogen-containing group, oxygen-containing group, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, and –⸾–OH, and (iii) Ra and Rb are each independently selected from the group consisting of C1 to C10 linear alkyl, C3 to C10 branched alkyl, C3 to C10 cyclic alkyl, C5 to C12 aryl, C2 to C10 linear or branched alkenyl and C2 to C10 linear or branched alkynyl, –⸾–NH-C1-C10 alkyl, and –⸾–OH-substituted C1-C10 alkyl, wherein the etching composition does not contain any added metal.

2. The etching composition of claim 1, wherein the one or more alkanolamines of formula I comprise monoethanolamine (MEA).

3. The etching composition of claim 1, wherein the one or more quaternary ammonium hydroxides comprises one or more of ETMAH and TMAH.

4. The etching composition of claim 1, wherein the one or more silicon-containing compounds of formula II are contained.

5. The etching composition of claim 1, comprising: A. 35% to 60% by weight of water; B. 20.0% to 70.0% by weight of monoethanolamine (MEA); C. 0.1% to 3% by weight of pure ethyltrimethylammonium hydroxide (ETMAH) or pure tetramethylammonium hydroxide (TMAH); and D. 0.15% to 2.0% by weight of pure [materials / materials].

6. The etching composition of claim 1, wherein the etching composition further comprises one or more other silicon-containing compounds selected from alkyl silsesquioxanes, vinyl silsesquioxanes, carboxylic acid alkyl silsesquioxanes and pentanediol alkyl silsesquioxanes.

7. The etching composition of claim 1, wherein the etching composition further comprises a water-miscible solvent containing hydroxyl groups selected from the group consisting of alkyldiols, polyols, diols, alkoxylols, saturated aliphatic monohydric alcohols, unsaturated nonaromatic monohydric alcohols and low molecular weight alcohols containing cyclic structures.

8. The etching composition of claim 1, wherein the etching composition further comprises one or more silicates.

9. The etching composition of claim 1, wherein the etching composition further comprises one or more surfactants.

10. The etching composition of claim 1, comprising: A. 20% to 55% by weight of water; B. 20% to 70% by weight of monoethanolamine (MEA); C. 0.1% to 2.5% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. 0.3% to 1.25% by weight of pure [unclear - possibly a specific ingredient or substance].

11. The etching composition of claim 1, comprising: A. about 52.6% by weight of water; B. about 46.5% by weight of monoethanolamine (MEA); C. about 0.4% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.5% by weight of pure...

12. The etching composition of claim 1, comprising: A. about 39% by weight of water; B. about 60% by weight of monoethanolamine (MEA); C. about 0.4% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.5% by weight of pure...

13. The etching composition of claim 1, comprising: A. about 29% by weight of water; B. about 70% by weight of monoethanolamine (MEA); C. about 0.4% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.5% by weight of pure...

14. The etching composition of claim 1, comprising: A. about 53% by weight of water; B. about 46% by weight of monoethanolamine (MEA); C. about 0.4% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.6% by weight of pure...

15. The etching composition of claim 1, comprising: A. about 53.6% by weight of water; B. about 45% by weight of monoethanolamine (MEA); C. about 0.4% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 1% by weight of pure...

16. The etching composition of claim 1, comprising: A. about 52% by weight of water; B. about 46.5% by weight of monoethanolamine (MEA); C. about 1% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.5% by weight of pure...

17. The etching composition of claim 1, comprising: A. about 51% by weight of water; B. about 46.5% by weight of monoethanolamine (MEA); C. about 2% by weight of pure ethyltrimethylammonium hydroxide (ETMAH); and D. about 0.5% by weight of pure...

18. The etching composition of claim 1, comprising: A. 45% to 55% by weight of water; B. 40% to 55% by weight of monoethanolamine (MEA); C. 0.1% to 2.5% by weight of pure tetramethylammonium hydroxide (TMAH); and D. 0.4% to 0.95% by weight of pure [unclear - possibly a specific ingredient or substance].

19. The etching composition of claim 1, comprising: A. about 52.5% by weight of water; B. about 45% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.5% by weight of pure...

20. The etching composition of claim 1, comprising: A. about 47.5% by weight of water; B. about 50% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.5% by weight of pure...

21. The etching composition of claim 1, comprising: A. about 47.514% by weight of water; B. about 50% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.5% by weight of pure...

22. The etching composition of claim 1, comprising: A. about 42.5% by weight of water; B. about 55% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.5% by weight of pure...

23. The etching composition of claim 1, comprising: A. about 42.514% by weight of water; B. about 55% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.486% by weight of pure...

24. The etching composition of claim 1, comprising: A. about 37.5% by weight of water; B. about 60% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.5% by weight of pure...

25. The etching composition of claim 1, comprising: A. about 37.514% by weight of water; B. about 60% by weight of monoethanolamine (MEA); C. about 2% by weight of pure tetramethylammonium hydroxide (TMAH); and D. about 0.486% by weight of pure...

26. A method for selectively increasing the etching rate of silicon relative to silicon dioxide on a semiconductor substrate comprising silicon and silicon dioxide, the method comprising the steps of: a. contacting the semiconductor substrate comprising silicon and silicon dioxide with an etching composition of any one of claims 1 to 25; and b. rinsing the semiconductor device after at least partially removing the silicon.

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