Etching composition

Abstract

The present disclosure relates to an etching composition useful for selectively removing silicon germanium (SiGe) from a semiconductor substrate as an intermediate step in a multi-stage semiconductor manufacturing process, for example.

Description

Technology Field

[0001] Cross-reference regarding related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 077,283 filed September 11, 2020, the entire contents of which are incorporated herein by reference.

[0003] Field of disclosure

[0004] The present disclosure relates to an etching composition and a process using the etching composition. In particular, the present disclosure relates to an etching composition capable of selectively etching silicon germanium in the presence of other exposed or underlying materials, such as a metal conductor (e.g., copper), a barrier material, or an insulating material (e.g., a low-k dielectric material). Background Technology

[0005] The semiconductor industry is rapidly reducing the size and increasing the density of electronic circuits and components, such as microelectronic devices, silicon chips, liquid crystal displays, MEMS (Micro Electro Mechanical Systems), and printed wiring boards. The integrated circuits within these devices are layered or stacked, with the thickness of the insulating layer between each circuit layer continuously decreasing and the feature size becoming increasingly smaller. As the feature size decreases, patterns become smaller, and device performance parameters become more stringent and robust. Consequently, as feature sizes become smaller, various problems that were previously acceptable are no longer acceptable or have become more significant issues.

[0006] In the manufacturing of advanced integrated circuits, both high-dielectric (high k) and low-dielectric (low k) insulators, along with various barrier layer materials, have been used to minimize problems associated with higher density and optimize performance.

[0007] Silicon germanium (SiGe) can be utilized as nanowires and / or nanosheets in the manufacture of semiconductor devices, liquid crystal displays, MEMS (micro-electromechanical systems), printed circuit boards, etc. For example, it can be used as a gate material in multi-gate devices such as multiple-gate field-effect transistors (FETs) (e.g., gate-all-around FETs). The problem to be solved

[0008] In the construction of semiconductor devices, silicon germanium (SiGe) requires frequent etching. In various types of applications and device environments for SiGe, other layers come into contact with or are otherwise exposed as this material is etched. For device yield and long lifespan, highly selective etching of SiGe in the presence of these other materials (e.g., metal conductors, dielectrics, and hard marks) is generally required. The etching process for SiGe can be a plasma etching process. However, using a plasma etching process on a SiGe layer can cause damage to either or both the gate insulation layer and the semiconductor substrate. Additionally, the etching process can remove a portion of the semiconductor substrate by etching the gate insulation layer exposed by the gate electrode. The electrical characteristics of the transistor can be negatively affected. To prevent such etching damage, additional protective device fabrication steps can be used, but they entail significant costs.

[0009] The present disclosure relates to a composition and a process for selectively etching SiGe with respect to a hard mask layer, a gate material (e.g., SiN, poly-Si, or SiOx) and a low dielectric constant layer (e.g., boron-doped SiGe, SiN, poly-Si, SiOx, carbon-doped oxide, or SiCO) present in a semiconductor device. More specifically, the present disclosure relates to a composition and a process for selectively etching SiGe with respect to a low dielectric constant layer, such as boron-doped SiGe, which can improve carrier mobility. means of solving the problem

[0010] In one aspect, the present disclosure features an etching composition comprising (1) at least one fluorine-containing acid containing hydrofluoric acid or hexafluorosilicic acid; (2) at least one oxidizing agent; (3) at least one inorganic acid different from the fluorine-containing acid; (4) at least one organic acid or anhydride thereof containing formic acid, acetic acid, propionic acid, or butyric acid; (5) at least one polymerized naphthalene sulfonic acid; and (6) at least one amine comprising the formula (I): N-R1R2R3, wherein R1 is a C1-C8 alkyl optionally substituted with OH or NH2, R2 is a C1-C8 alkyl optionally substituted with H or OH, and R3 is a C1-C8 alkyl optionally substituted with OH.

[0011] In another aspect, the present disclosure features an etching composition comprising (1) at least one fluorine-containing acid containing hydrofluoric acid or hexafluorosilicic acid; (2) at least one oxidizing agent; (3) at least one organic acid containing formic acid, acetic acid, propionic acid, or butyric acid or an anhydride thereof; (4) at least one polymerized naphthalene sulfonic acid or a salt thereof; (5) at least one amine comprising the formula (I): N-R1R2R3, wherein R1 is a C1-C8 alkyl optionally substituted with OH or NH2, R2 is a C1-C8 alkyl optionally substituted with H or OH, and R3 is a C1-C8 alkyl optionally substituted with OH; and (6) at least one glycol.

[0012] In another aspect, the present disclosure is characterized by a method comprising the step of removing a SiGe film by contacting a semiconductor substrate containing a SiGe film with an etching composition described herein.

[0013] In another aspect, the present disclosure features an article formed by the method described above, the article being a semiconductor device (e.g., an integrated circuit). Specific details for implementing the invention

[0014] As defined herein, unless otherwise specified, all expressed percentages should be understood as percentages by weight relative to the total weight of the composition.

[0015] Generally, the present disclosure features an etching composition (e.g., an etching composition for selectively removing SiGe) comprising (1) at least one fluorine-containing acid containing hydrofluoric acid or hexafluorosilicic acid; (2) at least one oxidizing agent; (3) at least one inorganic acid different from the fluorine-containing acid; (4) at least one organic acid or anhydride thereof containing formic acid, acetic acid, propionic acid, or butyric acid; (5) at least one polymerized naphthalene sulfonic acid; (6) at least one pyridine-containing compound; and (7) at least one amine comprising the formula (I): N-R1R2R3, wherein R1 is a C1-C8 alkyl optionally substituted with OH or NH2, R2 is a C1-C8 alkyl optionally substituted with H or OH, and R3 is a C1-C8 alkyl optionally substituted with OH.

[0016] In some embodiments, the etching composition of this disclosure may comprise at least one (e.g., two, three, or four) fluorine-containing acid. The fluorine-containing acid described herein may be an inorganic acid such as HF or H2SiF6. In some embodiments, at least one fluorine-containing acid is at least about 0.01 wt% (e.g., at least about 0.02 wt%, at least about 0.04 wt%, at least about 0.05 wt%, at least about 0.06 wt%, at least about 0.08 wt%, at least about 0.1 wt%, at least about 0.2 wt%, at least about 0.4 wt%, at least about 0.5 wt%, at least about 0.6 wt%, at least about 0.8 wt%, at least about 1 wt%, at least about 1.2 wt%, at least about 1.4 wt%, or at least about 1.5 wt%) to a maximum of about 2 wt% (e.g., a maximum of about 1.9 wt%, a maximum of about 1.8 wt%, a maximum of about 1.7 wt%, a maximum of about 1.6 wt%, a maximum of about 1.5 wt%, a maximum of about 1.2 wt%, a maximum of about 1 wt%, Or it is present in an amount of up to about 0.5 wt%. Although we do not wish to be bound by theory, it is believed that fluorine-containing acids can facilitate and enhance the removal of SiGe on a semiconductor substrate during the etching process. Meanwhile, fluorine-containing acids also increase the removal of certain dielectric materials (e.g., SiOx and boron-doped SiGe), and accordingly, in the etching compositions described herein, it is desirable that the amount thereof be limited so that the removal of these dielectric materials is minimized.

[0017] In some embodiments, the etching composition of this disclosure may include at least one (e.g., two, three, or four) oxidizing agent suitable for use in microelectronic applications. Examples of suitable oxidizing agents include oxidizing acids (e.g., nitric acid, permanganate, or potassium permanganate) and their salts, peroxides (e.g., hydrogen peroxide, dialkyl peroxide, urea hydrogen peroxide), persulfonic acids (e.g., hexafluoropropane persulfonic acid, methane persulfonic acid, trifluoromethane persulfonic acid, or p-toluene persulfonic acid) and their salts, ozone, peroxycarboxylic acids (e.g., peracetic acid) and their salts, perphosphoric acid and its salts, persulfuric acid and its salts (e.g., ammonium persulfate or tetramethylammonium persulfate), perchloric acid and its salts (e.g., ammonium perchlorate, sodium perchlorate, or It includes tetramethylammonium perchlorate), and periodic acid and its salts (e.g., periodic acid, ammonium periodicate, or tetramethylammonium periodicate). These oxidizing agents may be used alone or in combination.

[0018] In some embodiments, at least one oxidizing agent may be at least about 5 wt% (e.g., at least about 6 wt%, at least about 7 wt%, at least about 8 wt%, at least about 9 wt%, at least about 10 wt%, at least about 11 wt%, at least about 13 wt%, or at least about 15 wt%) to up to about 20 wt% (e.g., up to about 18 wt%, up to about 16 wt%, up to about 15 wt%, up to about 14 wt%, up to about 12 wt%, or up to about 10 wt%) of the etching composition of this disclosure. While not wishing to be bound by theory, it is believed that the oxidizing agent can facilitate and enhance the removal of SiGe on a semiconductor substrate.

[0019] In some embodiments, the etching composition of this disclosure may optionally comprise at least one (e.g., two, three, or four) catalyst. In some embodiments, the catalyst may be an acid different from a fluorine-containing acid. For example, the catalyst may be an acid that does not contain fluorine. Examples of suitable catalysts include sulfuric acid (H2SO4), sulfonic acid, and phosphonic acid.

[0020] Examples of suitable sulfonic acids include alkylsulfonic acids (including substituted or unsubstituted alkylsulfonic acids) and arylsulfonic acids (including substituted or unsubstituted arylsulfonic acids). Examples of suitable alkylsulfonic acids include methanesulfonic acid, trifluoromethanesulfonic acid (or triflic acid), and 2-hydroxyethanesulfonic acid (or isethionic acid). Examples of suitable arylsulfonic acids include p-toluenesulfonic acid and naphthalenesulfonic acid.

[0021] Examples of suitable phosphonic acids include the phosphonic acid of the following formula (II):

[0022] R-PO(OH)2(II)

[0023] In the above equation, R is H, C1-C 10 It is an alkyl or aryl. Examples of suitable phosphonic acids include unsubstituted phosphonic acid (H3PO3) and phenylphosphonic acid.

[0024] Although we do not wish to be bound by theory, it is believed that including a catalyst in the etching composition described herein can increase the rate of formation of pericylate (such as peracetic acid), which can enhance SiGe removal together with fluorine-containing acid. Additionally, it is believed that the catalyst can significantly suppress the removal of certain dielectric materials (e.g., SiOx) from the semiconductor substrate during the etching process.

[0025] In some embodiments, at least one catalyst is present in an amount of at least about 0.1 wt% (e.g., at least about 0.2 wt%, at least about 0.4 wt%, at least about 0.5 wt%, at least about 0.6 wt%, at least about 0.8 wt%, at least about 1 wt%, at least about 1.2 wt%, at least about 1.4 wt%, or at least about 1.5 wt%) to a maximum of about 5 wt% (e.g., a maximum of about 4.5 wt%, a maximum of about 4 wt%, a maximum of about 3.5 wt%, a maximum of about 3 wt%, a maximum of about 2.5 wt%, a maximum of about 2 wt%, a maximum of about 1.5 wt%, or a maximum of about 1 wt%) of the etching composition of this disclosure. In some embodiments, at least one catalyst may be omitted from the etching composition of this disclosure (e.g., when the etching composition comprises glycol).

[0026] In some embodiments, the etching composition of this disclosure may comprise at least one (e.g., two, three, or four) organic acid or anhydride thereof. In some embodiments, the organic acid may be formic acid, acetic acid, propionic acid, or butyric acid. In some embodiments, the organic acid anhydride may be formic anhydride, acetic anhydride, propionic anhydride, or butyric anhydride. In some embodiments, the etching composition may comprise both an organic acid and an anhydride (e.g., an anhydride of an organic acid). Without wishing to be confined to theory, it is believed that organic acids or anhydrides thereof can facilitate and enhance the removal of SiGe on a semiconductor substrate.

[0027] In some embodiments, at least one organic acid or anhydride thereof may be at least about 30 wt% (e.g., at least about 35 wt%, at least about 40 wt%, at least about 45 wt%, at least about 50 wt%, at least about 55 wt%, or at least about 60 wt%) to up to about 90 wt% (e.g., up to about 85 wt%, up to about 80 wt%, up to about 75 wt%, up to about 70 wt%, up to about 65 wt%, up to about 60 wt%, up to about 55 wt%, up to about 50 wt%, up to about 45 wt%, or up to about 40 wt%) of the etching composition of this disclosure.

[0028] In some embodiments, the etching composition of this disclosure may comprise at least one polymerized naphthalene sulfonic acid (or poly(naphthalene sulfonic acid)) or a salt thereof, for example, as a surfactant or a selective inhibitor. In some embodiments, the polymerized naphthalene sulfonic acid may be a sulfonic acid having the following chemical structure:

[0029]

[0030] In the above formula, n is 3, 4, 5, or 6. Commercially available examples of such polymerized naphthalene sulfonic acid include the Takesurf A-47 series products available from Takemoto Oil & Fat Co., Ltd. Although we do not wish to be bound by theory, it is believed that polymerized naphthalene sulfonic acid or its salts can selectively inhibit the removal of SiN, poly-Si, and SiCO when SiGe is removed from a semiconductor substrate using the etching composition of this disclosure.

[0031] In some embodiments, at least one polymerized naphthalene sulfonic acid or salt thereof may be at least about 0.001 wt% (e.g., at least about 0.005 wt%, at least about 0.01 wt%, at least about 0.02 wt%, at least about 0.03 wt%, at least about 0.04 wt%, at least about 0.05 wt%, or at least about 0.1 wt%) to a maximum of about 0.15 wt% (e.g., a maximum of about 0.14 wt%, a maximum of about 0.12 wt%, a maximum of about 0.1 wt%, a maximum of about 0.08 wt%, a maximum of about 0.06 wt%, a maximum of about 0.05 wt%, or a maximum of about 0.02 wt%) of the etching composition of this disclosure.

[0032] In some embodiments, the etching composition of this disclosure may optionally comprise at least one (e.g., two, three, or four) pyridine-containing compound. For example, the pyridine-containing compound may comprise pyridine optionally substituted with a C1-C6 alkyl (e.g., methyl or ethyl), a pyridine-containing acid, a pyridine-containing alcohol, or a salt thereof (e.g., an HCl salt thereof). Examples of suitable pyridine-containing compounds include picolinic acid, dipicolinic acid, nicotinic acid, isonicotinic acid, 2-amino-isonicotinic acid, isonicotinic acid N-oxide, 4-pyridylacetic acid, 3-pyridylacetic acid, 2-pyridylacetic acid, 4-pyridinepropanol, 3-pyridinepropanol, 2-methylpyridine, 3-methylpyridine, and salts thereof (e.g., HCl salts of acids). Although I do not wish to be bound by theory, it is believed that pyridine-containing compounds can selectively inhibit the removal of boron-doped SiGe (which is necessary for carrier mobility improvement) when SiGe is removed from a semiconductor substrate using the etching composition of this disclosure.

[0033] In some embodiments, at least one pyridine-containing compound is present in an amount of at least about 0.01 wt% (e.g., at least about 0.02 wt%, at least about 0.04 wt%, at least about 0.05 wt%, at least about 0.06 wt%, at least about 0.08 wt%, at least about 0.1 wt%, at least about 0.2 wt%, at least about 0.3 wt%, at least about 0.4 wt%, or at least about 0.5 wt%) to a maximum of about 1 wt% (e.g., a maximum of about 0.9 wt%, a maximum of about 0.8 wt%, a maximum of about 0.7 wt%, a maximum of about 0.6 wt%, a maximum of about 0.5 wt%, a maximum of about 0.4 wt%, a maximum of about 0.2 wt%, or a maximum of about 0.1 wt%) of the etching composition of this disclosure.

[0034] In some embodiments, the etching composition of this disclosure may comprise at least one (e.g., two, three, or four) amine. In some embodiments, the amine may be an amine of formula (I): N-R1R2R3, wherein R1 is a C1-C8 alkyl optionally substituted with OH or NH2, R2 is a C1-C8 alkyl optionally substituted with H or OH, and R3 is a C1-C8 alkyl optionally substituted with OH. Examples of suitable amines of formula (I) include diisopropylamine, N-butyldiethanolamine, N-(3-aminopropyl)-diethanolamine, N-octylglucamine, N-ethylglucamine, N-methylglucamine, and 1-[bis(2-hydroxyethyl)amino]-2-propanol. Although I do not wish to be bound by theory, it is believed that amines can selectively inhibit the removal of SiN, poly-Si, and SiCO when SiGe is removed from a semiconductor substrate using the etching composition of this disclosure.

[0035] In some embodiments, at least one amine may be at least about 0.001 wt% (e.g., at least about 0.002 wt%, at least about 0.005 wt%, at least about 0.008 wt%, at least about 0.01 wt%, at least about 0.02 wt%, at least about 0.05 wt%, or at least about 0.1 wt%) to a maximum of about 0.15 wt% (e.g., a maximum of about 0.14 wt%, a maximum of about 0.12 wt%, a maximum of about 0.1 wt%, a maximum of about 0.08 wt%, a maximum of about 0.06 wt%, or a maximum of about 0.05 wt%) of the etching composition of this disclosure.

[0036] In some embodiments, the etching composition of this disclosure may comprise water as a solvent. In some embodiments, the water may be deionized and ultrapure water, and may not contain organic contaminants and have a minimum resistivity of about 4 megaohms to about 17 megaohms, or at least about 17 megaohms. In some embodiments, water is present in an amount of at least about 10 wt% (e.g., at least about 15 wt%, at least about 20 wt%, at least about 25 wt%, at least about 30 wt%, at least about 35 wt%, or at least about 40 wt%) to a maximum of about 50 wt% (e.g., a maximum of about 45 wt%, a maximum of about 40 wt%, a maximum of about 35 wt%, a maximum of about 30 wt%, a maximum of about 25 wt%, a maximum of about 20 wt%, or a maximum of about 15 wt%) of the etching composition. While not bound by theory, it is believed that if the amount of water exceeds 50 weight percent of the composition, it will result in a high etch rate of Si and SiOx, which must be minimized during the etching process. Meanwhile, while not bound by theory, it is believed that the etching composition of this disclosure must contain a certain amount of water (e.g., at least about 10 weight percent) to keep all other components in a solubilized state and prevent degradation of etching performance. Furthermore, while not bound by theory, it is believed that reducing the amount of water within the above range can significantly suppress the removal of certain dielectric materials (e.g., boron-doped SiGe) from the semiconductor substrate during the etching process.

[0037] In some embodiments, the etching composition of this disclosure may optionally further comprise at least one (e.g., two, three, or four) organic solvent. In some embodiments, at least one organic solvent may comprise an ester, an alcohol, or an alkylene glycol ether. Examples of suitable organic solvents include propyl acetate, propylene glycol, hexylene glycol, 1,3-propanediol, ethylene glycol monobutyl ether (EGBE), and 3-methoxy-3-methyl-1-butanol. In some embodiments, at least one organic solvent may be at least about 10 wt% (e.g., at least about 15 wt%, at least about 20 wt%, at least about 25 wt%, at least about 30 wt%, or at least about 35 wt%) to a maximum of about 40 wt% (e.g., a maximum of about 35 wt%, a maximum of about 30 wt%, a maximum of about 25 wt%, a maximum of about 20 wt%, or a maximum of about 15 wt%) of the etching composition.

[0038] In embodiments of the etching composition of this disclosure in which glycols are included, the catalyst may be optional (i.e., included in the etching composition or omitted). Examples of suitable glycols include propylene glycol, hexylene glycol, and ethylene glycol monobutyl ether (EGBE). While not wishing to be confined to theory, it is believed that including glycols in the etching composition of this disclosure can suppress the etching rate of certain dielectric materials (such as SiOx).

[0039] In some embodiments, the etching composition of this disclosure may optionally further comprise at least one (e.g., two, three, or four) polyamine (e.g., polyethyleneimine). In some embodiments, the at least one polyamine may be at least about 0.001 wt% (e.g., at least about 0.002 wt%, at least about 0.005 wt%, at least about 0.01 wt%, at least about 0.02 wt%, at least about 0.04 wt%, or at least about 0.05 wt%) to a maximum of about 0.5 wt% (e.g., a maximum of about 0.4 wt%, a maximum of about 0.3 wt%, a maximum of about 0.2 wt%, a maximum of about 0.1 wt%, a maximum of about 0.08 wt%, a maximum of about 0.06 wt%, or a maximum of about 0.05 wt%) of the etching composition. Although I do not wish to be bound by theory, it is believed that including polyamine in the etching composition of this disclosure can suppress the etching rate of boron-doped SiGe.

[0040] In some embodiments, the etching composition of the present invention may optionally further comprise at least one (e.g., two, three, or four) silane (e.g., 3-aminopropyltriethoxysilane). In some embodiments, at least one silane comprises a silane of the following formula (III):

[0041] Si-R4R5R6R7(III)

[0042] In the above formula, R4, R5, R6, and R7 are each independently N(RR'), RC(O)O, C1-C8 alkoxy (e.g., methoxy or ethoxy), N(RR') or Si(R a R b R c C1-C optionally substituted with ) 18 It is an alkyl group (e.g., methyl, butyl, hexyl, octyl, dodecyl, or octadecyl). R and R' are each independently H or C1-C 10 It is alkyl, and R a , R b, and R c Each independently C1-C 10 alkyl or C1-C 10 It is an alkoxy. Examples of suitable silanes include 3-aminopropyl triethoxysilane, methyltrimethoxysilane, dimethylaminotrimethylsilane, acetoxytrimethylsilane, octyltrimethoxysilane, butyltrimethoxysilane, dodecyltrimethoxysilane, hexyltrimethoxysilane, octadecyltrimethoxysilane, or bis(trimethoxysilyl)methane.

[0043] In some embodiments, at least one silane may be at least about 0.001 wt% (e.g., at least about 0.002 wt%, at least about 0.005 wt%, at least about 0.01 wt%, at least about 0.02 wt%, at least about 0.04 wt%, or at least about 0.05 wt%) to a maximum of about 0.5 wt% (e.g., a maximum of about 0.4 wt%, a maximum of about 0.3 wt%, a maximum of about 0.2 wt%, a maximum of about 0.1 wt%, a maximum of about 0.08 wt%, a maximum of about 0.06 wt%, or a maximum of about 0.05 wt%) of the etching composition. While not wishing to be bound by theory, it is believed that including a silane in the etching composition of this disclosure can suppress the etching rate of boron-doped SiGe.

[0044] In some embodiments, the etching composition of this disclosure may optionally further comprise at least one (e.g., two, three, or four) sugar alcohol (e.g., mannitol or sorbitol). In some embodiments, the at least one sugar alcohol may be at least about 0.001 wt% (e.g., at least about 0.002 wt%, at least about 0.005 wt%, at least about 0.01 wt%, at least about 0.02 wt%, or at least about 0.05 wt%) to a maximum of about 0.1 wt% (e.g., a maximum of about 0.08 wt%, a maximum of about 0.06 wt%, a maximum of about 0.05 wt%, a maximum of about 0.04 wt%, a maximum of about 0.02 wt%, or a maximum of about 0.01 wt%) of the etching composition. Although I do not wish to be bound by theory, it is believed that including sugar alcohol in the etching composition of this disclosure can suppress the polysilicon etching rate.

[0045] In some embodiments, the etching composition of this disclosure may optionally further comprise at least one (e.g., two, three, or four) boronic acid. For example, the boronic acid may be of the following formula: RB(OH)2, wherein R is C1-C 10 It is an alkyl, aryl, or heteroaryl, wherein the aryl or heteroaryl is 1 to 6 (e.g., 1, 2, 3, 4, 5, or 6) C1-C 10 It can be optionally substituted with alkyl groups. Examples of suitable boronic acids include phenylboronic acid and naphthalene-1-boronic acid.

[0046] In some embodiments, at least one boronic acid may be at least about 0.01 wt% (e.g., at least about 0.02 wt%, at least about 0.05 wt%, at least about 0.1 wt%, at least about 0.2 wt%, or at least about 0.3 wt%) to a maximum of about 0.5 wt% (e.g., a maximum of about 0.4 wt%, a maximum of about 0.3 wt%, a maximum of about 0.2 wt%, a maximum of about 0.1 wt%, a maximum of about 0.08 wt%, or a maximum of about 0.05 wt%) of the etching composition. While not wishing to be bound by theory, it is believed that including boronic acid in the etching composition of this disclosure can suppress the SiOx etching rate.

[0047] In some embodiments, the etching composition of this disclosure may have a pH of at least about 0 (e.g., at least about 0.2, at least about 0.4, at least about 0.5, at least about 0.6, at least about 0.8, at least about 1, at least about 1.2, at least about 1.4, at least about 1.5, at least about 1.6, at least about 1.8, at least about 2, at least about 2.2, at least about 2.4, or at least about 2.5) and / or up to about 3 (e.g., up to about 2.8, up to about 2.6, up to about 2.5, up to about 2.4, up to about 2.2, up to about 2, or up to about 1.5). Although I do not wish to be bound by theory, it is believed that etching compositions with a pH higher than 3 may not have sufficient SiGe selectivity for low dielectric materials (e.g., SiOx) because such etching compositions may have significantly increased etching rates for low dielectric materials. Additionally, it is believed that etching compositions with a pH lower than 0 may decompose certain components within the composition due to strong acidity.

[0048] Additionally, in some embodiments, the etching composition of the present disclosure may contain additives as optional components, such as pH adjusters, corrosion inhibitors, surfactants, additional organic solvents, biocides, and defoaming agents. Examples of suitable additives include alcohols (e.g., polyvinyl alcohol), organic acids (e.g., iminidiacetic acid, malonic acid, oxalic acid, succinic acid, and malic acid), and inorganic acids (e.g., boric acid). Examples of suitable defoaming agents include polysiloxane defoaming agents (e.g., polydimethylsiloxane), polyethylene glycol methyl ether polymers, ethylene oxide / propylene oxide copolymers, and glycidyl ether-capped acetylene-based diol ethoxylates (such as those described in U.S. Patent No. 6,717,019 incorporated herein by reference). Examples of suitable surfactants may be cationic, anionic, nonionic, or amphoteric.

[0049] Generally, the etching composition of the present disclosure may have a relatively high etch selectivity for SiGe / dielectric materials (e.g., boron-doped SiGe (SiGe:B), SiN, polysilicon, or SiCO) (i.e., a high ratio of the SiGe etching rate to the dielectric material etching rate). In some embodiments, the etching composition may have an etch selectivity for SiGe / dielectric materials (e.g., SiGe / SiGe:B) of at least about 2 (e.g., at least about 3, at least about 4, at least about 5, at least about 6, at least about 7, at least about 8, at least about 9, at least about 10, at least about 15, at least about 20, at least about 30, at least about 40, or at least about 50) and / or up to about 500 (e.g., up to about 100).

[0050] In some embodiments, when the etching composition of the present disclosure has more than one additive component, one or more of the additive components may be specifically excluded in any combination. These components include polymers, oxygen scavengers, quaternary ammonium compounds (including quaternary ammonium hydroxide (such as TMAH) and salts thereof), amines, bases (such as alkaline bases (e.g., NaOH, KOH, and LiOH) and organic bases), surfactants, defoamers, fluoride-containing compounds (e.g., H2PF6, HBF4, NH4F, and tetraalkylammonium fluoride), abrasives, silicates, hydroxycarboxylic acids containing more than two hydroxyl groups, carboxylic acids and polycarboxylic acids (e.g., those without amino groups), silanes (e.g., alkoxysilanes), cyclic compounds (e.g., azoles (such as diazole, triazole, or tetrazole), triazines, and cyclic compounds containing at least two rings, such as substituted or unsubstituted naphthalene or substituted or unsubstituted biphenyl ether), buffers, and corrosion inhibitors (azole or selected from the group consisting of non-azole corrosion inhibitors), guanidine, guanidine salts, pyrrolidone, polyvinylpyrrolidone, metal salts (e.g., metal halides), and catalysts (e.g., metal-containing catalysts).

[0051] The etching composition of this disclosure may be prepared simply by mixing the components together or by blending two compositions in a kit. The first composition in the kit may be an aqueous solution of an oxidizing agent (e.g., H2O2). The second composition in the kit may contain the remaining components of the etching composition of this disclosure in a predetermined ratio in a concentrated form such that the blending of the two compositions produces the desired etching composition of this disclosure.

[0052] In some embodiments, the present disclosure features a method for etching a semiconductor substrate containing at least one SiGe film (e.g., a film containing SiGe). The method may include the step of removing the SiGe film by contacting the semiconductor substrate containing at least one SiGe film with the etching composition of the present disclosure. The method may further include the step of rinsing the semiconductor substrate with a rinse solvent after the contact step and / or drying the semiconductor substrate after the rinse step. In some embodiments, the method does not substantially remove a metal conductor (e.g., Cu) or dielectric material (e.g., SiN, polysilicon, SiCO, or boron-doped SiGe) from the semiconductor substrate. For example, the method does not remove a metal conductor or dielectric material exceeding about 5 weight percent (e.g., more than about 3 weight percent or more than about 1 weight percent) from the semiconductor substrate.

[0053] In some embodiments, the SiGe film in the semiconductor substrate may contain at least about 10 atomic percent (e.g., at least about 12 atomic percent, at least about 14 atomic percent, at least about 15 atomic percent, at least about 16 atomic percent, at least about 18 atomic percent, or at least about 20 atomic percent) of Ge and / or up to about 65 atomic percent (e.g., up to about 60 atomic percent, up to about 55 atomic percent, up to about 50 atomic percent, up to about 45 atomic percent, up to about 40 atomic percent, up to about 35 atomic percent, up to about 34 atomic percent, up to about 32 atomic percent, up to about 30 atomic percent, up to about 28 atomic percent, up to about 26 atomic percent, up to about 25 atomic percent, up to about 24 atomic percent, up to about 22 atomic percent, up to about 20 atomic percent, up to about 18 atomic percent, up to about 16 atomic percent, or up to about 15 atomic percent) of Ge in the SiGe film. As used herein, "atomic % (at%)" represents an atomic percentage equivalent to a molar percentage. Although we do not wish to be bound by theory, it is believed that SiGe films containing about 10 atomic % to about 35 atomic % of Ge can be more easily removed from a semiconductor substrate by an etching composition compared to films containing more than 35 atomic % or less than 10 atomic % of Ge.

[0054] In some embodiments, the etching method comprises the following steps:

[0055] (A) A step of providing a semiconductor substrate containing a SiGe film;

[0056] (B) a step of contacting a semiconductor substrate with the etching composition described herein;

[0057] (C) a step of rinsing the semiconductor substrate with one or more suitable rinsing solvents; and

[0058] (D) Optionally, a step of drying the semiconductor substrate (e.g., by any suitable means that removes the rinsing solvent and does not impair the integrity of the semiconductor substrate).

[0059] In this method, the semiconductor substrate containing SiGe to be etched may contain organic and organometallic residues and various metal oxides, some or all of which may be removed during the etching process.

[0060] The semiconductor substrate (e.g., wafer) described herein is generally composed of silicon, a III-V compound such as silicon germanium, GaAs, or any combination thereof. The semiconductor substrate may additionally contain exposed integrated circuit structures such as interconnect features (e.g., metal lines and dielectric materials). Metals and metal alloys used for interconnect features include, but are not limited to, aluminum, aluminum alloyed with copper, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, and tungsten. The semiconductor substrate may also contain layers of interlayer dielectric, polysilicon, silicon oxide, silicon nitride, silicon carbide, titanium oxide, and carbon-doped silicon oxide.

[0061] A semiconductor substrate may be brought into contact with an etching composition by any suitable method, such as placing the etching composition into a tank and immersing and / or submerging the semiconductor substrate in the etching composition, spraying the etching composition onto the semiconductor substrate, streaming the etching composition onto the semiconductor substrate, or any combination thereof.

[0062] The etching composition of the present disclosure can be effectively used up to a temperature of about 85°C (e.g., about 20°C to about 80°C, about 55°C to about 65°C, or about 60°C to about 65°C). Since the etching rate of SiGe increases with temperature in this range, the process can proceed for a shorter time at higher temperatures. Conversely, lower etching temperatures generally require a longer etching time.

[0063] The etching time can vary widely depending on the specific etching method, thickness, and temperature used. When etching in an immersion batch type process, a suitable time range is, for example, up to about 10 minutes (e.g., about 1 minute to about 7 minutes, about 1 minute to about 5 minutes, or about 2 minutes to about 4 minutes). The etching time for a single wafer process may be in the range of about 30 seconds to about 5 minutes (e.g., about 30 seconds to about 4 minutes, about 1 minute to about 3 minutes, or about 1 minute to about 2 minutes).

[0064] Mechanical stirring means may be used to further enhance the etching ability of the etching composition of the present disclosure. Examples of suitable stirring means include circulation of the etching composition over a substrate, streaming or spraying of the etching composition over a substrate, and ultrasonic or megasonic stirring during the etching process. The orientation of the semiconductor substrate relative to the surface may be at any angle. Horizontal or vertical orientation is preferred.

[0065] After etching, the semiconductor substrate may be rinsed with a suitable rinsing solvent for about 5 seconds to about 5 minutes, with or without stirring means. Multiple rinsing steps using different rinsing solvents may be used. Examples of suitable rinsing solvents include, but are not limited to, deionized (DI) water, methanol, ethanol, isopropyl alcohol, N-methylpyrrolidinone, gamma-butyrolactone, dimethyl sulfoxide, ethyl lactate, and propylene glycol monomethyl ether acetate. Alternatively or additionally, an aqueous rinse solution (such as dilute aqueous ammonium hydroxide) with a pH > 8 may be used. Examples of rinsing solvents include, but are not limited to, dilute aqueous ammonium hydroxide, deionized water, methanol, ethanol, and isopropyl alcohol. The rinsing solvent may be applied using means similar to those used to apply the etching composition described herein. The etching composition may have been removed from the semiconductor substrate before the start of the rinsing step, or may still be in contact with the semiconductor substrate at the start of the rinsing step. In some embodiments, the temperature used in the rinsing step is 16°C to 27°C.

[0066] Optionally, the semiconductor substrate is dried after the rinsing step. Any suitable drying means known in the art may be used. Examples of suitable drying means include spin drying, flow of drying gas over the semiconductor substrate, heating of the semiconductor substrate with a heating means such as a hot plate or infrared lamp, Marangoni drying, rotagoni drying, IPA drying, or any combination thereof. The drying time will vary depending on the specific method used, but is generally about 30 seconds to a few minutes.

[0067] In some embodiments, the etching method described herein further includes the step of forming a semiconductor device (e.g., an integrated circuit device such as a semiconductor chip) from a semiconductor substrate obtained by the method described above.

[0068] The present disclosure is further illustrated in detail with reference to the following embodiments, which are for illustrative purposes only and should not be construed as limiting the scope of the present disclosure.

[0069] Examples

[0070] All listed percentages are based on weight (weight%) unless otherwise specified.

[0071] Stirring control during the test was performed with a 1-inch stirring rod at 250 rpm, unless otherwise specified.

[0072] General Procedure 1

[0073] formulation blending

[0074] Samples of the etching composition were prepared by adding the remaining components of the formulation to a calculated amount of solvent while stirring. After a homogeneous solution was formed, optional additives were added if used.

[0075] General Procedure 2

[0076] Materials and Methods

[0077] For evaluation, measurements of the etching rates of blanket films on the film were performed using commercially available unpatterned 300 mm diameter wafers cut into 0.5"×1.0" test coupons. The main blanket film materials used in the test were: 1) a SiGe film containing 20 atomic% Ge with a thickness of approximately 500 Å deposited on a silicon substrate (SiGe20-1); 2) a boron-doped SiGe film containing 25 atomic% Ge with a thickness of approximately 250 Å deposited on a silicon substrate (SiGe25:B); 3) a SiGe film containing 30 atomic% Ge with a thickness of approximately 400 Å deposited on a silicon substrate (SiGe30-1); and 4) a SiGe film containing 20 atomic% Ge with a thickness of approximately 500 Å deposited on a silicon substrate (SiGe20-2). 5) a SiGe film containing 25 atomic% Ge with a thickness of about 500 Å deposited on a silicon substrate (SiGe25); 6) a SiGe film containing 30 atomic% Ge with a thickness of about 530 Å deposited on a silicon substrate (SiGe30-2); 7) a SiGe film containing 50 atomic% Ge with a thickness of about 590 Å deposited on a silicon substrate (SiGe50); 8) a SiGe film containing 65 atomic% Ge with a thickness of about 240 Å deposited on a silicon substrate (SiGe65); and 9) a SiOx film (SiOx) with a thickness of about 1250 Å deposited on a silicon substrate.

[0078] To determine the etching rate of the blanket film, blanket film test coupons were measured for thickness before and after treatment. The film thickness before and after treatment was measured by ellipsometry using Woollam VASE.

[0079] General Procedure 3

[0080] Etching evaluation using the beaker test

[0081] All blanket film etching tests were performed at room temperature (21–23°C) or specified control temperatures in a 125 mL glass beaker containing 100 g of sample solution with continuous stirring at 250 rpm, with the cap always kept in place to minimize evaporation loss. All blanket test coupons having a blanket dielectric film with one side exposed to the sample solution were cut into 0.5"×1.0" square test coupon sizes using a diamond scribe for beaker scale testing. Each individual test coupon was secured in place using a single 4" long locking plastic tweezers clip. The test coupons, with one edge secured by the locking tweezers clip, were suspended inside a 100 mL PFA bottle and immersed in 100 g of the test solution while continuously stirring the solution at 250 rpm at room temperature (or the specified control temperature). The test coupons were left in the stirred solution until the treatment time (as described in General Procedure 3A) had elapsed. After the treatment time in the test solution had elapsed, the sample coupons were immediately removed from the 100 mL PFA bottle and rinsed according to General Procedure 3A. After the final IPA rinse step, all test coupons were subjected to a filtered nitrogen gas blow-off step using a handheld nitrogen gas blower to forcibly remove all trace amounts of IPA, thereby producing a final dry sample for test measurement.

[0082] General Procedure 3A (Blanket Test Coupon)

[0083] Immediately after a treatment time of 2 to 10 minutes according to General Procedure 3, the coupon was immersed in 300 mL of ultra-high purity deionized (DI) water with gentle stirring for 15 seconds, then immersed in 300 mL of isopropyl alcohol (IPA) with gentle stirring for 15 seconds, and finally rinsed in 300 mL of IPA with gentle stirring for 15 seconds. The process treatment was completed according to General Procedure 3.

[0084] Example 1

[0085] Formulation Examples 1 to 31 (FE-1 to FE-31) were prepared according to General Procedure 1. The formulations are summarized in Table 1.

[0086] Table 1

[0087]

[0088]

[0089] Formulation Examples 1 to 31 (FE-1 to FE-31) were evaluated for the etching rate of a blanket wafer having a SiGe film containing 20 atomic% Ge (SiGe20-1) and a blanket wafer having a boron-doped SiGe film containing 25 atomic% Ge (SiGe25:B) according to general procedures 2 and 3A. The SiGe film was etched for 1 minute at 25°C, and the boron-doped SiGe film was etched for 2 minutes at 25°C. The evaluation results are summarized in Table 2.

[0090] Table 2

[0091]

[0092] As shown in Table 2, FE-1 to FE-31 all exhibited relatively high SiGe20 / SiGe25:B etching selectivity ratios. That is, these formulations can effectively remove SiGe films while minimizing the removal of exposed boron-doped SiGe on the semiconductor substrate during the etching process.

[0093] Comparative formulations Examples 1 to 6 (CFE-1 to CFE-6) were prepared according to general procedure 1. The formulations are summarized in Table 3.

[0094] Table 3

[0095]

[0096] Comparative formulation Examples 1 to 6 (CFE-1 to CFE-6) were evaluated for the etching rates of blanket wafers containing SiGe20-1 films and blanket wafers containing SiGe25:B films according to general procedures 2 and 3A. SiGe films were etched for 1 minute at 25°C, and boron-doped SiGe films were etched for 2 minutes at 25°C. The evaluation results are summarized in Table 4.

[0097] Table 4

[0098]

[0099] As shown in Table 3, CFE-1 to CFE-6 did not contain sulfuric acid or pyridine-containing compounds, and CFE-1 and CFE-2 also did not contain Takesurf A-47Q. As a result, Table 4 shows that these formulations exhibited relatively high SiGe25:B etching rates and relatively low SiGe20 / SiGe25:B etching rate selectivity ratios.

[0100] Example 2

[0101] Formulation Examples 32 to 42 (FE-32 to FE-42) were prepared according to General Procedure 1. The formulations are summarized in Table 5.

[0102] Table 5

[0103]

[0104] Formulation Examples 32 to 42 (FE-32 to FE-42) were evaluated for etching rates on a blanket wafer containing a SiGe film (SiGe30-1) containing 30 atomic% Ge and a blanket wafer containing a SiOx film, in accordance with general procedures 2 and 3A. The SiGe30 film was etched for 1 minute at 25°C, and the SiOx film was etched for 2 minutes at 25°C. FE-32 and FE-38 were also evaluated for etching rates on SiGe25:B (2 minutes at 25°C), SiGe20-2 (1 minute at 25°C), SiGe25 (1 minute at 25°C), SiGe30-2 (1 minute at 25°C), SiGe50 (1 minute at 25°C), and SiGe65 (15 seconds at 25°C). The evaluation results are summarized in Table 6.

[0105] Table 6

[0106]

[0107] As shown in Table 6, FE-32 to FE-42 all exhibited relatively high SiGe30 etching rates even without containing any pyridine-containing compounds. Additionally, Table 6 shows that formulations containing a relatively small amount of HF (e.g., FE-38) significantly reduce the SiOx etching rate, thereby inhibiting the removal of SiOx during the etching process. Furthermore, the results show that FE-32 and FE-38 exhibited increased SiGe etching rates when the SiGe film contained an increased amount of Ge.

[0108] Example 3

[0109] Formulation Examples 43 to 55 (FE-43 to FE-55) were prepared according to General Procedure 1. The formulations are summarized in Table 7.

[0110] Table 7

[0111]

[0112] According to general procedures 2 and 3A, Formulation Examples 43 to 44 (FE-43 to FE-44) were evaluated for the etching rate of a blanket wafer having a SiGe film (SiGe20-1) containing 20 atomic% Ge and a blanket wafer having a boron-doped SiGe film (SiGe25:B) containing 25 atomic% Ge. The SiGe20 film was etched for 1 minute at 25°C, and the SiGe25:B film was etched for 2 minutes at 25°C. The evaluation results are summarized in Table 8.

[0113] Table 8

[0114]

[0115] As shown in Table 8, FE-43 to FE-50 and FR-52 to FE-55 (containing silane) exhibited a relatively low SiGe25:B etching rate and a relatively high SiGe20 / SiGe25:B etching selectivity ratio. That is, these formulations can effectively remove the SiGe film while minimizing the removal of exposed boron-doped SiGe on the semiconductor substrate during the etching process.

[0116] Example 4

[0117] Formulations Examples 56 and 57 (FE-56 and FE-57) were prepared according to General Procedure 1. The formulations are summarized in Table 9.

[0118] Table 9

[0119]

[0120] According to general procedures 2 and 3A, formulations Examples 56 and 57 (FE-56 to FE-57) were evaluated for etching rates on blanket wafers containing the following films: SiOx (2 min at 25°C), SiGe25:B (2 min at 25°C), SiGe20-2 (1 min at 25°C), SiGe25 (1 min at 25°C), SiGe30-2 (1 min at 25°C), SiGe50 (1 min at 25°C), and SiGe65 (15 sec at 25°C). The evaluation results are summarized in Table 10.

[0121] Table 10

[0122]

[0123] As shown in Table 10, by reducing the amounts of HF and water, both FE-56 and FE-57 exhibited relatively low etching rates of SiOx and SiGe25:B, thereby suppressing the removal of SiOx and SiGe25:B during the etching process. In addition, the above results show that FE-56 and FE-57 exhibited a relatively good SiGe / SiGe25:B etching selectivity ratio.

[0124] Example 5

[0125] Formulations Examples 58 and 59 (FE-58 and FE-59) were prepared according to General Procedure 1. The formulations are summarized in Table 11.

[0126] Table 11

[0127]

[0128] According to general procedures 2 and 3A, formulations Examples 58 and 59 (FE-58 to FE-59) were evaluated for etching rates on blanket wafers containing the following films: SiOx (2 min at 25°C), SiGe20-1 (1 min at 25°C), and SiGe25:B (2 min at 25°C). The evaluation results are summarized in Table 12.

[0129] Table 12

[0130]

[0131] As shown in Table 11, FE-58 did not contain sulfuric acid but contained propylene glycol as an organic solvent, whereas FE-59 did not contain sulfuric acid but contained methanesulfonic acid as a catalyst and propylene glycol as an organic solvent. Table 12 shows that the two formulations exhibited a relatively low SiOx etching rate and a relatively high SiGe20 / SiGe25:B etching selectivity ratio.

[0132] Although the present invention has been described in detail with reference to specific embodiments thereof, modifications and variations will be understood to be within the spirit and scope of what is described and claimed.

Claims

Claim 1 An etching composition comprising: at least one fluorine-containing acid including hydrofluoric acid or hexafluorosilicic acid; at least one oxidizing agent; at least one catalyst including sulfuric acid, sulfonic acid, or phosphonic acid; at least one organic acid including formic acid, acetic acid, propionic acid, or butyric acid or anhydride thereof; at least one polymerized naphthalene sulfonic acid or a salt thereof; at least one amine comprising an amine of formula (I): N-R1R2R3, wherein R1 is a C1-C8 alkyl optionally substituted with OH or NH2, R2 is a C1-C8 alkyl optionally substituted with H or OH, and R3 is a C1-C8 alkyl optionally substituted with OH; and at least one pyridine-containing compound comprising a pyridine optionally substituted with a C1-C6 alkyl, a pyridine-containing acid, a pyridine-containing alcohol, or a salt thereof. Claim 2 An etching composition according to claim 1, wherein at least one fluorine-containing acid is present in an amount of 0.01 weight% to 2 weight% of the composition. Claim 3 An etching composition according to claim 1, wherein at least one oxidizing agent comprises hydrogen peroxide or peracetic acid. Claim 4 An etching composition according to claim 1, wherein at least one oxidizing agent is present in an amount of 5% to 20% by weight of the composition. Claim 5 An etching composition according to claim 1, wherein at least one catalyst comprises sulfuric acid, methanesulfonic acid, phosphonic acid, or phenylphosphonic acid. Claim 6 An etching composition according to claim 1, wherein at least one catalyst is present in an amount of 0.1 weight% to 5 weight% of the composition. Claim 7 An etching composition according to claim 1, wherein at least one organic acid or anhydrous thereof comprises acetic acid or acetic anhydride. Claim 8 An etching composition according to claim 1, wherein at least one organic acid or its anhydride is present in an amount of 30% to 90% by weight of the composition. Claim 9 In claim 1, at least one polymerized naphthalene sulfonic acid comprises a sulfonic acid having the following structure: An etching composition in which, in the above formula, n is 3 to 6. Claim 10 An etching composition according to claim 1, wherein at least one polymerized naphthalene sulfonic acid or a salt thereof is present in an amount of 0.001 weight% to 0.15 weight% of the composition. Claim 11 An etching composition according to claim 1, wherein at least one pyridine-containing compound comprises picolinic acid, dipicolinic acid, nicotinic acid, isonicotinic acid, 2-amino-isonicotinic acid, isonicotinic acid N-oxide, 4-pyridylacetic acid, 3-pyridylacetic acid, 2-pyridylacetic acid, 4-pyridinepropanol, 3-pyridinepropanol, 2-methylpyridine, 3-methylpyridine, or a salt thereof. Claim 12 An etching composition according to claim 1, wherein at least one pyridine-containing compound is present in an amount of 0.01 weight% to 1 weight% of the composition. Claim 13 In claim 1, the amine of formula (I) is diisopropylamine, N-butyldiethanolamine, N-(3-aminopropyl)-diethanolamine, N-octylglucamine, N-ethylglucamine, N-methylglucamine, or 1-[bis(2-hydroxyethyl)amino]-2-propanol, etching composition. Claim 14 An etching composition according to claim 1, wherein at least one amine is present in an amount of 0.001 weight% to 0.15 weight% of the composition. Claim 15 An etching composition according to claim 1, further comprising at least one organic solvent. Claim 16 An etching composition according to claim 15, wherein at least one organic solvent comprises an ester, an alcohol, or an alkylene glycol ether. Claim 17 An etching composition according to claim 15, wherein at least one organic solvent comprises propyl acetate, propylene glycol, hexylene glycol, 1,3-propanediol, or ethylene glycol butyl ether. Claim 18 An etching composition according to claim 15, wherein at least one organic solvent is present in an amount of 10% to 40% by weight of the composition. Claim 19 An etching composition according to claim 1, further comprising water. Claim 20 An etching composition according to claim 19, wherein water is present in an amount of 10% to 50% by weight of the composition. Claim 21 An etching composition according to claim 1, further comprising at least one silane. Claim 22 In paragraph 21, at least one silane comprises a silane of the following formula (III): Si-R4R5R6R7(III) wherein R4, R5, R6, and R7 are each independently N(RR'), RC(O)O, C1-C8 alkoxy, N(RR') or Si(R a R b R c C1-C optionally substituted with ) 18 alkyl, where R and R' are each independently H or C1-C 10 It is alkyl, and R a , R b , and R c Each independently C1-C 10 alkyl or C1-C 10 Alkoxyne, etching composition. Claim 23 An etching composition according to claim 22, wherein at least one silane comprises 3-aminopropyl triethoxysilane, methyltrimethoxysilane, dimethylaminotrimethylsilane, acetoxytrimethylsilane, octyltrimethoxysilane, butyltrimethoxysilane, dodecyltrimethoxysilane, hexyltrimethoxysilane, octadecyltrimethoxysilane, or bis(trimethoxysilyl)methane. Claim 24 An etching composition according to claim 21, wherein at least one silane is present in an amount of 0.001 weight% to 0.5 weight% of the composition. Claim 25 In claim 1, the composition is an etching composition having a pH of 0 to 3. Claim 26 An etching composition comprising: at least one fluorine-containing acid including hydrofluoric acid or hexafluorosilicic acid; at least one oxidizing agent; at least one catalyst including sulfuric acid, sulfonic acid, or phosphonic acid; at least one organic acid including formic acid, acetic acid, propionic acid, or butyric acid or anhydride thereof; at least one polymerized naphthalene sulfonic acid or a salt thereof; at least one amine comprising an amine of formula (I): N-R1R2R3, wherein R1 is a C1-C8 alkyl optionally substituted with OH or NH2, R2 is a C1-C8 alkyl optionally substituted with H or OH, and R3 is a C1-C8 alkyl optionally substituted with OH; at least one pyridine-containing compound including a pyridine optionally substituted with a C1-C6 alkyl, a pyridine-containing acid, a pyridine-containing alcohol, or a salt thereof; and at least one glycol. Claim 27 A method comprising the step of removing the SiGe film by contacting a semiconductor substrate containing the SiGe film with the composition of claim 1. Claim 28 In claim 27, the method wherein the SiGe film comprises 10 atomic% to 65 atomic% of Ge. Claim 29 A method according to claim 27, further comprising the step of rinsing the semiconductor substrate with a rinse solvent after the contact step. Claim 30 A method according to claim 29, further comprising a step of drying a semiconductor substrate after a rinsing step. Claim 31 A method according to claim 27, wherein SiN, poly-Si, SiCO, or boron-doped SiGe is not removed in excess of 5 weight percent. Claim 32 In an article formed by the method of paragraph 27, the article is a semiconductor device. Claim 33 In Paragraph 32, the semiconductor device is an article that is an integrated circuit. Claim 34 delete

Images