Composition for cleaning semiconductor substrates, and method for cleaning semiconductor substrates and method for manufacturing them

Abstract

The present invention provides a composition for cleaning a semiconductor substrate, the composition having a high tungsten oxide removal rate, while having Ti / W etching selectivity.　A composition for cleaning a semiconductor substrate, the composition containing (A) an oxidant, (B) a fluorine compound, (C) a tungsten metal corrosion inhibitor and (D) a tungsten oxide etching accelerator, wherein: the addition ratio of the oxidant (A) is 0.0001% to 10% by mass relative to the total mass of the composition for cleaning a semiconductor substrate; the addition ratio of the fluorine compound (B) is 0.005% to 10% by mass relative to the total mass of the composition for cleaning a semiconductor substrate; and the addition ratio of the tungsten metal corrosion inhibitor (C) is 0.0001% to 5% by mass relative to the total mass of the composition for cleaning a semiconductor substrate.

Description

[Technical Field]

[0001] The present invention relates to a composition for cleaning semiconductor substrates, as well as a method for cleaning and manufacturing semiconductor substrates. [Background technology]

[0002] In recent years, there has been an increasing demand for further miniaturization and enhanced functionality of semiconductor devices, leading to advancements in technologies such as miniaturization and 3D integration of semiconductor substrates.

[0003] For semiconductor substrates that enable miniaturization and high functionality of such semiconductor devices, metallic tungsten is suitably used as the material. Metallic tungsten can be deposited by CVD (chemical vapor deposition), and has characteristics such as low electromigration, low electrical resistance, and high heat resistance. For this reason, metallic tungsten is used in embedded word lines in memory elements such as DRAM, and in contact holes in logic elements such as CPUs.

[0004] It is known that the embedded word lines of a memory element can be manufactured by, for example, the following method: A barrier film made of silicon oxide, titanium, or titanium nitride, and a metallic tungsten film are sequentially deposited on a silicon substrate having recesses formed by etching. Next, the film is planarized by CMP (chemical mechanical polishing), and then the barrier film and the metallic tungsten film, or the metallic tungsten film, are selectively etched by dry etching or the like (CMP may be omitted). Subsequently, the embedded word lines of the memory element are manufactured by selectively etching the barrier film (Non-Patent Literature 1).

[0005] Furthermore, it is known that via holes for logic elements can be manufactured, for example, by a damascene process or a dual damascene process. Here, the damascene process is described as an example. First, a hard mask made of titanium or titanium nitride and a resist film are formed on a laminate of a silicon substrate having a transistor and a metal tungsten plug, and an insulating layer, and a pattern is formed on the resist film by exposure and development. Next, the pattern on the resist film is used to form the pattern of the hard mask by dry etching (the resist may be selectively removed thereafter as needed). Furthermore, the insulating film of the laminate is etched using the pattern of the hard mask as a mask by dry etching to form via holes for connecting to the metal tungsten plug. After that, the hard mask is selectively removed by etching to manufacture the via holes for the logic element.

[0006] In other words, in either case, the process includes a step that selectively removes titanium or titanium alloys such as titanium nitride without damaging the metallic tungsten (a selective etching step for titanium and titanium alloys). Therefore, when manufacturing small and high-performance semiconductor devices using metallic tungsten, a semiconductor substrate cleaning agent is required that etches titanium or titanium alloys without etching metallic tungsten (high Ti / W etching selectivity).

[0007] As an example of such a semiconductor substrate cleaning agent, Patent Document 1 describes an invention relating to a composition for selectively removing titanium nitride and / or photoresist etching residue material from the surface of a microelectronic device having titanium nitride and / or photoresist etching residue material. In this case, the composition is characterized by comprising at least one oxidizing agent, at least one etching solution, and at least one solvent, and substantially free of hydrogen peroxide. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Special Publication No. 2015-506583 [Non-patent literature]

[0009] [Non-Patent Document 1] SPCC 2019 Technical Program, "Wet Etchant for DRAM Word-line Titanium Nitride Recess with Selectivity to Tungsten", Wilson et al., [https: / / www.linx-consulting.com / wp-content / uploads / 2019 / 04 / 03-15-W_Yeh-Dupont-Wet_Etchant_for_DRAM_Word_line_TiN_Recess_with_Selectivity_to_W.pdf] [Overview of the project] [Problems that the invention aims to solve]

[0010] However, it has been found that when semiconductor substrates are manufactured using a semiconductor substrate cleaning composition such as that described in Patent Document 1, semiconductor devices with the desired performance may not be obtained. One possible reason for this is the influence of tungsten oxide formed by oxidation of the surface of the metallic tungsten film during the semiconductor substrate manufacturing process. For example, in the embedded word lines of memory elements, if tungsten oxide is present covering the surface of titanium nitride, the semiconductor substrate cleaning composition may not be able to contact the titanium nitride, making it impossible to etch the titanium nitride. On the other hand, in via holes of logic elements, since the electrical resistance of tungsten oxide is higher than that of metallic tungsten, the presence of tungsten oxide on the surface of metallic tungsten may increase the electrical resistance of the tungsten plug.

[0011] Although it is considered that the performance and yield of the semiconductor substrate can be improved by selectively removing the tungsten oxide, providing a separate process for removing tungsten oxide complicates the manufacturing process and increases the manufacturing cost. Therefore, it is preferable to simultaneously remove tungsten oxide in the selective etching process of titanium and titanium alloy. In this case, if the removal rate of tungsten oxide is slow, the time required for the selective etching process of titanium and titanium alloy becomes long, so the production efficiency (throughput) of the semiconductor substrate decreases. Furthermore, when there are variations in the thickness of tungsten oxide, etching of some exposed metallic tungsten may proceed due to the rapid removal of some tungsten oxide. Therefore, it is preferable that the removal rate of tungsten oxide by the semiconductor substrate cleaning composition is high.

[0012] Therefore, the present invention provides a semiconductor substrate cleaning composition having a Ti / W etching selectivity and a high removal rate of tungsten oxide.

Means for Solving the Problems

[0013] As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by adding a tungsten oxide etching accelerator to the semiconductor substrate cleaning composition, and have completed the present invention. That is, the present invention is as follows, for example.

[0014] [1] A semiconductor substrate cleaning composition comprising (A) an oxidizing agent, (B) a fluorine compound, (C) a metallic tungsten anticorrosive agent, and (D) a tungsten oxide etching accelerator, wherein the addition rate of the (A) oxidizing agent is 0.0001 to 10% by mass with respect to the total mass of the semiconductor substrate cleaning composition, the addition rate of the (B) fluorine compound is 0.005 to 10% by mass with respect to the total mass of the semiconductor substrate cleaning composition, the addition rate of the (C) metallic tungsten anticorrosive agent is 0.0001 to 5% by mass with respect to the total mass of the semiconductor substrate cleaning composition. [2] The semiconductor substrate cleaning composition according to [1], wherein the addition rate of (D) tungsten oxide etching accelerator is 0.01 to 20% by mass with respect to the total mass of the semiconductor substrate cleaning composition. [3] The semiconductor substrate cleaning composition according to [1] or [2] above, wherein the (A) oxidizing agent comprises at least one selected from the group consisting of peracids, halogen oxoacids, and salts thereof. [4] The semiconductor substrate cleaning composition according to any one of [1] to [3] above, wherein the (B) fluorine compound comprises at least one selected from the group consisting of hydrogen fluoride (HF), tetrafluoroboric acid (HBF4), hexafluorosilicic acid (H2SiF6), hexafluorozirconium acid (H2ZrF6), hexafluorotitanium acid (H2TiF6), hexafluorophosphoric acid (HPF6), hexafluoroaluminic acid (H2AlF6), hexafluorogermanic acid (H2GeF6), and salts thereof. [5] The (C) metal tungsten corrosion inhibitor is the following formula (1): [ka] (In the above formula (1), R 1 This includes alkyl groups having 5 to 30 carbon atoms, substituted or unsubstituted alkyl(poly)heteroalkylene groups, substituted or unsubstituted aryl(poly)heteroalkylene groups, and the following formula (2): [ka] (In the above formula, Cy is a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 15 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 15 carbon atoms. A is an alkylene with 1 to 5 carbon atoms, independently of each other. r is either 0 or 1. Z is given by the following formula: [ka] It is one of the following. It is a base represented by, R 2 These are, independently, substituted or unsubstituted C1-C18 alkyl groups and substituted or unsubstituted C6-C20 aryl groups. X is a halide ion, hydroxide ion, organic sulfonate ion, tetrafluoroborate, or hexafluorophosphate. A semiconductor substrate cleaning composition according to any one of the above [1] to [4], comprising at least one selected from the group consisting of an ammonium salt represented by and a heteroaryl salt having an alkyl group having 5 to 30 carbon atoms. [6] The semiconductor substrate cleaning composition according to any one of [1] to [5] above, wherein the (D) tungsten oxide etching accelerator comprises at least one selected from the group consisting of hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, 10-camphorsulfonic acid, and salts thereof. [7] The semiconductor substrate cleaning composition according to [6] above, wherein the salt is an ammonium salt. [8] A semiconductor substrate cleaning composition according to any of [1] to [7] above, wherein the pH is 0.1 to 5.0. [9] A semiconductor substrate cleaning composition according to any one of [1] to [8] above, which is a semiconductor substrate cleaning composition for etching tungsten oxide while suppressing the etching of metallic tungsten.

[10] A method for cleaning a semiconductor substrate, comprising the step of contacting a semiconductor substrate having a layer containing metallic tungsten, a layer containing at least one of titanium and a titanium alloy, and a layer containing tungsten oxide with a semiconductor substrate cleaning composition according to any of [1] to [9] above to remove at least a portion of the layer containing at least one of titanium and a titanium alloy and the layer containing tungsten oxide.

[11] A method for manufacturing a semiconductor substrate, comprising the step of contacting a semiconductor substrate having a layer containing metallic tungsten, a layer containing at least one of titanium and a titanium alloy, and a layer containing tungsten oxide with a semiconductor substrate cleaning composition according to any of [1] to [9] above to remove at least a portion of the layer containing at least one of titanium and a titanium alloy and the layer containing tungsten oxide. [Effects of the Invention]

[0015] The present invention provides a semiconductor substrate cleaning composition that has Ti / W etching selectivity while also having a high rate of tungsten oxide removal. [Brief explanation of the drawing]

[0016] [Figure 1] This is a schematic diagram illustrating the application of the semiconductor substrate cleaning composition of the present invention to a semiconductor substrate for memory elements. [Figure 2] This is a schematic diagram illustrating the application of the semiconductor substrate cleaning composition of the present invention to a semiconductor substrate for logic elements. [Modes for carrying out the invention]

[0017] The embodiments for carrying out the present invention will be described in detail below.

[0018] <Composition for cleaning semiconductor substrates> The semiconductor substrate cleaning composition according to the present invention comprises (A) an oxidizing agent, (B) a fluorine compound, (C) a metallic tungsten corrosion inhibitor, and (D) a tungsten oxide etching accelerator. In this case, the addition rate of the (A) oxidizing agent is 0.0001 to 10% by mass of the total mass of the semiconductor substrate cleaning composition, the addition rate of the (B) fluorine compound is 0.005 to 10% by mass of the total mass of the semiconductor substrate cleaning composition, and the addition rate of the (C) metallic tungsten corrosion inhibitor is 0.0001 to 5% by mass of the total mass of the semiconductor substrate cleaning composition.

[0019] The semiconductor substrate cleaning composition according to the present invention allows for selective etching of layers containing titanium and / or titanium alloys in a semiconductor substrate while suppressing the etching of layers containing metallic tungsten (W). Specifically, because the etching rate of titanium and / or titanium alloys (Ti) is higher than that of metallic tungsten (W), the etching selectivity ratio (hereinafter sometimes referred to as the "Ti / W etching selectivity ratio") is increased.

[0020] In this case, the titanium alloy is not particularly limited as long as it has metallic properties obtained by adding one or more metallic or nonmetallic elements other than titanium to titanium, but examples include alloys of titanium and at least one element selected from the group consisting of aluminum, oxygen, nitrogen, carbon, molybdenum, vanadium, niobium, iron, chromium, nickel, tin, hafnium, zirconium, palladium, ruthenium, and platinum. Of these, titanium nitride and titanium oxide are preferred, and titanium nitride is more preferred. In this specification, "titanium alloy" means a titanium alloy in which the titanium element content is 20 atomic weight % or more of the total atomic weight of the titanium alloy. The titanium element content in the titanium alloy is preferably 25 atomic weight % or more, more preferably 30 atomic weight %, even more preferably 35 atomic weight %, and particularly preferably 40 to 99.9 atomic weight % of the total atomic weight of the titanium alloy.

[0021] Furthermore, the semiconductor substrate cleaning composition according to the present invention significantly increases the etching rate of tungsten oxide formed on the surface of the tungsten-containing material of the semiconductor substrate, allowing for effective removal of tungsten oxide. In this specification, "tungsten oxide" refers to the material formed by the oxidation of tungsten oxide, and usually means tungsten(VI)(WO3).

[0022] The present invention will be described below with reference to the drawings. Note that the drawings may be exaggerated for illustrative purposes and may differ from the actual dimensions.

[0023] Figure 1 is a schematic diagram showing the application of the semiconductor substrate cleaning composition of the present invention to a semiconductor substrate for memory elements. The semiconductor substrate for memory elements (before cleaning) 10 has a silicon substrate 11 having recesses, an insulating film 12 made of silicon oxide, a barrier film 13 made of titanium nitride, and a metallic tungsten film 14. Such a semiconductor substrate for memory elements (before cleaning) 10 can be manufactured by sequentially depositing an insulating film made of silicon oxide, a barrier film made of titanium nitride, and a metallic tungsten film on a silicon substrate having recesses, and then performing planarization by CMP (chemical mechanical polishing), dry etching, etc., to selectively etch the barrier film and the metallic tungsten film (CMP may be omitted). Here, the semiconductor substrate for memory elements (before cleaning) 10 has tungsten oxide 15 formed by the oxidation of metallic tungsten on the barrier film 13 and the metallic tungsten film 14. Therefore, even when attempting to selectively etch the barrier film 13 made of titanium nitride using a semiconductor substrate cleaning composition, the tungsten oxide is present covering the surface of the barrier film 13, preventing the semiconductor substrate cleaning composition from contacting the barrier film 13 and thus making it impossible to etch the barrier film 13.

[0024] When the semiconductor substrate cleaning composition of the present invention is applied to a semiconductor substrate for memory elements (before cleaning) 10 having such a configuration, the tungsten oxide 15 can be suitably removed due to the high etching rate of tungsten oxide. For this reason, the semiconductor substrate cleaning composition of the present invention can come into contact with the barrier film 13 made of titanium nitride, and the barrier film can be selectively etched due to a high Ti / W etching selectivity ratio. As a result, a semiconductor substrate for memory elements (after cleaning) 20 can be manufactured, which is formed by laminating a silicon substrate 21 having recesses, an insulating film 22 made of silicon oxide, an etched barrier film 23 made of titanium nitride, and a metallic tungsten film 24.

[0025] Figure 2 is a schematic diagram showing the application of the semiconductor substrate cleaning composition of the present invention to a semiconductor substrate for logic elements. The semiconductor substrate for logic elements (before cleaning) 30 is shown in its state after via hole formation. Specifically, the semiconductor substrate for logic elements (before cleaning) 30 has an insulating film 32 made of silicon oxide formed on a silicon substrate (not shown) having transistors, a hard mask 33 made of patterned titanium nitride placed on the insulating film 32, and a metallic tungsten plug 34 placed within the insulating film 32. Such a semiconductor substrate for logic elements (before cleaning) 30 can be manufactured by the following method. First, a hard mask made of titanium nitride and a resist film are formed on a laminate of a silicon substrate having transistors and metallic tungsten plugs and an insulating layer, and a pattern is formed on the resist film by exposure and development. Next, the patterned resist film is used to form the pattern of the hard mask by dry etching and remove the resist film. Furthermore, by using the pattern of the hard mask as a mask and etching the insulating film of the laminate by dry etching, a semiconductor substrate for logic elements (before cleaning) 30 with via holes can be manufactured. Here, the semiconductor substrate 30 for logic elements (before cleaning) has tungsten oxide 35 formed by the oxidation of metallic tungsten on a metallic tungsten plug 34. The presence of tungsten oxide 35 on the surface of the metallic tungsten plug 34 can increase the electrical resistance of the metallic tungsten plug 34.

[0026] When the semiconductor substrate cleaning composition of the present invention is applied to a semiconductor substrate for logic elements (before cleaning) 30 having such a configuration, the hard mask 33 made of titanium nitride can be selectively removed due to the high Ti / W etching selectivity ratio. Furthermore, because the semiconductor substrate cleaning composition of the present invention has a high etching rate for tungsten oxide, tungsten oxide 35 can also be removed. As a result, a semiconductor substrate for logic elements (after cleaning) 40 can be manufactured having an insulating film 42 made of silicon oxide formed on a silicon substrate (not shown) having a transistor, and a metallic tungsten plug 44 disposed within the insulating film 42.

[0027] The following describes each component contained in the semiconductor substrate cleaning composition according to the present invention.

[0028] [(A) Oxidizing agent] (A) The oxidizing agent has the function of changing the oxidation state of titanium in titanium or titanium alloy to tetravalent and dissolving it in the semiconductor substrate cleaning composition.

[0029] (A) The oxidizing agents are not particularly limited, but include peracids, halogen oxoacids, and salts thereof.

[0030] Examples of the aforementioned peracids include hydrogen peroxide, persulfuric acid, percarbonate, superphosphate, peracetic acid, perbenzoic acid, and metachloroperbenzoic acid.

[0031] Examples of halogen oxoacids include chlorine oxoacids such as hypochlorous acid, chlorous acid, chloric acid, and perchloric acid; bromine oxoacids such as hypobromous acid, bromous acid, bromic acid, and perbromic acid; and iodine oxoacids such as hypoiodic acid, iodous acid, iodic acid, and periodic acid.

[0032] Examples of the salts include alkali metal salts such as lithium salts, sodium salts, potassium salts, rubidium salts, and cesium salts of the above-mentioned peracids or halogen oxoacids; alkaline earth metal salts such as beryllium salts, magnesium salts, calcium salts, strontium salts, and barium salts of the above-mentioned peracids or halogen oxoacids; metal salts such as aluminum salts, copper salts, zinc salts, and silver salts of the above-mentioned peracids or halogen oxoacids; and ammonium salts of the above-mentioned peracids or halogen oxoacids.

[0033] The oxidizing agent (A) described above is preferably hydrogen peroxide or iodine oxoacid, more preferably hydrogen peroxide, iodate, or periodic acid, even more preferably hydrogen peroxide or iodate, and particularly preferably iodate, as these result in higher WO3 / W etching selectivity and Ti / W etching selectivity.

[0034] The oxidizing agent (A) described above may be used alone or in combination of two or more. That is, in one embodiment, the oxidizing agent (A) preferably contains at least one selected from the group consisting of peracids, halogen oxoacids, and salts thereof, more preferably contains at least one selected from the group consisting of hydrogen peroxide and iodine oxoacids, even more preferably contains at least one selected from the group consisting of hydrogen peroxide, iodic acid, and periodic acid, particularly preferably contains at least one selected from the group consisting of hydrogen peroxide and iodic acid, and most preferably contains iodic acid.

[0035] (A) The addition rate of the oxidizing agent is 0.0001 to 10% by mass, preferably 0.001 to 5% by mass, more preferably 0.003 to 3% by mass, and even more preferably 0.01 to 2% by mass, based on the total mass of the semiconductor substrate cleaning composition. (A) When the addition rate of the oxidizing agent is within the above range, it is preferable from the viewpoint of increasing the WO3 / W etching selectivity ratio and the Ti / W etching selectivity ratio.

[0036] [(B) Fluorine compounds] (B) Fluorine compounds have functions such as promoting the etching of titanium or titanium alloys.

[0037] The fluorine compounds (B) mentioned above are not particularly limited, but include hydrogen fluoride (HF), tetrafluoroboric acid (HBF4), hexafluorosilicic acid (H2SiF6), hexafluorozirconium acid (H2ZrF6), hexafluorotitanium acid (H2TiF6), hexafluorophosphate (HPF6), hexafluoroaluminic acid (H2AlF6), hexafluorogermanic acid (H2GeF6), and salts thereof.

[0038] Examples of the salts mentioned above include ammonium salts such as ammonium fluoride (NH4F), ammonium tetrafluoroborate (NH4BF4), ammonium hexafluorosilicate ((NH4)2SiF6), and tetramethylammonium tetrafluoroborate (N(CH3)4BF4).

[0039] Of the above, (B) the fluorine compound is preferably hydrogen fluoride (HF), tetrafluoroboric acid (HBF4), hexafluorosilicic acid (H2SiF6), and salts thereof, more preferably hydrogen fluoride (HF), ammonium fluoride (NH4F), and hexafluorosilicic acid (H2SiF6), and even more preferably hydrogen fluoride (HF) because it provides a high WO3 / W etching selectivity and Ti / W etching selectivity.

[0040] Furthermore, the fluorine compounds (B) mentioned above may be used alone or in combination of two or more types. In other words, in a preferred embodiment, the (B) fluorine compound preferably comprises at least one selected from the group consisting of hydrogen fluoride (HF), tetrafluoroboric acid (HBF4), hexafluorosilicic acid (H2SiF6), hexafluorozirconium acid (H2ZrF6), hexafluorotitanium acid (H2TiF6), hexafluorophosphoric acid (HPF6), hexafluoroaluminic acid (H2AlF6), hexafluorogermanic acid (H2GeF6), and salts thereof; more preferably comprises at least one selected from the group consisting of hydrogen fluoride (HF), tetrafluoroboric acid (HBF4), hexafluorosilicic acid (H2SiF6), and salts thereof; even more preferably comprises at least one selected from the group consisting of hydrogen fluoride (HF), ammonium fluoride (NH4F), and hexafluorosilicic acid (H2SiF6); and particularly preferably comprises hydrogen fluoride (HF).

[0041] (B) The addition rate of the fluorine compound is 0.005 to 10% by mass, preferably 0.01 to 5% by mass, more preferably 0.03 to 3% by mass, and even more preferably 0.03 to 1% by mass, based on the total mass of the semiconductor substrate cleaning composition. (B) When the addition rate of the fluorine compound is within the above range, it is preferable from the viewpoint of improving the etching rate of titanium and titanium alloys and increasing the Ti / W etching selectivity ratio.

[0042] [(C) Metallic Tungsten Corrosion Inhibitor] (C) The metallic tungsten corrosion inhibitor has the function of adsorbing onto metallic tungsten to form a protective film and preventing or suppressing etching by semiconductor substrate cleaning compositions.

[0043] The (C) metal tungsten corrosion inhibitor is not particularly limited, but examples include ammonium salts represented by the following formula (1) and heteroaryl salts having an alkyl group with 5 to 30 carbon atoms.

[0044] [ka]

[0045] In the above formula, R 1 This includes alkyl groups having 5 to 30 carbon atoms, substituted or unsubstituted alkyl(poly)heteroalkylene groups, substituted or unsubstituted aryl(poly)heteroalkylene groups, and the following formula (2):

[0046] [ka]

[0047] This is a group represented by the following formula: Here, in formula (2), Cy is a substituted or unsubstituted (hetero)cycloalkyl group or a substituted or unsubstituted (hetero)aryl group, A is independently an alkylene having 1 to 5 carbon atoms, r is 0 or 1, and Z is represented by the following formula:

[0048] [ka]

[0049] It is one of the following. In this case, * represents the position where it bonds with the nitrogen (N) atom in formula (1). This makes it easier to adsorb onto metallic tungsten, thereby enhancing the corrosion-resistant function of metallic tungsten.

[0050] The alkyl group having 5 to 30 carbon atoms is not particularly limited, and examples thereof include a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an icosyl group, and the like.

[0051] The alkyl(poly)heteroalkylene group is -(C n H 2n -Z-) m -R 3 and is represented by. At this time, n is independently 1 to 5, preferably 1 to 3, more preferably 1 to 2. m is 1 to 5, preferably 1 to 2. Z is independently an oxygen atom (O), a sulfur atom (S), or a phosphorus atom (P), preferably an oxygen atom (O). R 3 is an alkyl group having 1 to 30 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an icosyl group, and the like.

[0052] The alkyl(poly)heteroalkylene group may have a substituent. The substituent is usually substituted with the hydrogen atom of R 3 . The substituent when the alkyl(poly)heteroalkylene group has a substituent is not particularly limited, and examples thereof include an aryl group having 6 to 20 carbon atoms such as a phenyl group and a naphthyl group; an alkoxy group having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group, and a propyloxy group; a hydroxy group; a cyano group; a nitro group, and the like. Note that the substituent may be one or two or more.

[0053] The aryl(poly)heteroalkylene group is -(C n H 2n -Z-) mIt is represented as -Ar. In this case, n is independently 1 to 5, preferably 1 to 3, and more preferably 1 to 2. m is 1 to 5, preferably 1 to 2. Z is independently an oxygen atom (O), a sulfur atom (S), or a phosphorus atom (P), preferably an oxygen atom (O). Ar is an aryl group having 6 to 18 carbon atoms, such as a phenyl group, naphthyl group, or anthracenyl group.

[0054] The aryl(poly)heteroalkylene group may have substituents. These substituents are usually substituted for hydrogen atoms of Ar. While not particularly limited, examples of substituents on the aryl(poly)heteroalkylene group include C1-C10 alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, and 1,1,3,3-tetramethylbutyl; C1-C6 alkoxy groups such as methoxy, ethoxy, and propyloxy; hydroxyl groups; cyano groups; and nitro groups. The group may have one substituent or two or more substituents.

[0055] In formula (2), Cy is a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C2-C10 heterocycloalkyl group, a substituted or unsubstituted C6-C15 aryl group, or a substituted or unsubstituted C2-C15 heteroaryl group. The C3-C10 cycloalkyl group is not particularly limited, but examples include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups. The C2-C10 heterocycloalkyl group is not particularly limited, but examples include pyrrolidinyl, piperidyl, tetrahydrofuranyl, tetrahydropyranyl, and tetrahydrothienyl groups. The C6-C15 aryl group is not particularly limited, but examples include phenyl. The heteroaryl group having 2 to 15 carbon atoms is not particularly limited, but examples include pyrrolyl group, imidazolyl group, pyrazolyl group, oxazolyl group, isoxazolyl group (isoxazolyl group), thiazolyl group, isothiazolyl group, pyridyl group, pyridyl group, pyridazyl group, pyrimidyl group, quinolyl group, isoquinolyl group, etc.

[0056] When the C3-C10 cycloalkyl group, C2-C10 heterocycloalkyl group, C6-C15 aryl group, or C2-C15 heteroaryl group has substituents, the substituents are not particularly limited, but include C1-C10 alkyl groups such as methyl, ethyl, propyl, isopropyl, and butyl groups; C1-C6 alkoxy groups such as methoxy, ethoxy, and propyloxy groups; vinyloxy groups, butene-1-eneoxy groups, and -OC(CF3)= Examples include alkenyloxy groups such as the group represented by CF{(CF3)2}; aryl groups having 6 to 10 carbon atoms such as phenyl and tolyl groups; heteroaryl groups having 3 to 10 carbon atoms such as pyrrolyl, pyridyl, imidazolyl, oxazolyl, isoxazolyl, pyrimidyl, and 4-amino-2-oxo-1,2-dihydropyrimidine-1-yl groups; hydroxyl groups; cyano groups; nitro groups; and alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, and propyloxy groups. Note that there may be one substituent or two or more substituents.

[0057] A is an alkylene having 1 to 5 carbon atoms, independently of each other. The alkylene having 1 to 5 carbon atoms is not particularly limited, but examples include methylene (-CH2-), ethylene (-C2H4-), propylene (-C3H6-), isopropylene (-CH(CH3)CH2-), etc.

[0058] Also, r is either 0 or 1.

[0059] Furthermore, Z is one of the following:

[0060] [ka]

[0061] In this case, one or two of the hydroxyl groups in the structure derived from monophosphate or diphosphate may be in the form of anions. Specifically, it may have the following structure:

[0062] [ka]

[0063] In this case, in equation (1), R 1 Since a counterion of the ammonium cation will be present inside, ammonium salt X - It may not have it.

[0064] The following structures are preferred as the group represented by formula (2).

[0065] [ka]

[0066] Of these, R 1The group is preferably an alkyl group having 6 to 20 carbon atoms, a substituted or unsubstituted aryl(poly)oxyalkylene group, more preferably an alkyl group having 8 to 18 carbon atoms, a substituted or unsubstituted phenyl(poly)oxyalkylene group, an octyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, a phenyloxyethyl (Ph-O-C2H4-) group, a phenyldi(oxyethylene)(Ph-(O-C2H4)2-) group, or a p-(1,1,3,3-tetramethylbutyl) group. It is more preferably a phenyldi(oxyethylene)(p-CH3C(CH3)2CH2C(CH3)2-Ph-(O-C2H4)2-) group, particularly preferably a decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, or p-(1,1,3,3-tetramethylbutyl)phenyldi(oxyethylene)(p-CH3C(CH3)2CH2C(CH3)2-Ph-(O-C2H4)2-) group, and most preferably a tetradecyl group, hexadecyl group, or octadecyl group.

[0067] The aforementioned R 2 These are, independently, substituted or unsubstituted C1-C18 alkyl groups and substituted or unsubstituted C6-C20 aryl groups.

[0068] The alkyl group having 1 to 18 carbon atoms is not particularly limited, but examples include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, etc.

[0069] Examples of substituents when an alkyl group having 1 to 18 carbon atoms has substituents include aryl groups having 6 to 20 carbon atoms such as phenyl and naphthyl groups; alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, and propyloxy groups; hydroxyl groups; cyano groups; and nitro groups.

[0070] The aryl group having 6 to 20 carbon atoms is not particularly limited, but examples include the phenyl group, naphthyl group, and biphenyl group.

[0071] Examples of substituents when an aryl group having 6 to 20 carbon atoms has substituents include alkyl groups having 1 to 10 carbon atoms such as methyl, ethyl, propyl, and isopropyl groups; alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, and propyloxy groups; hydroxyl groups; cyano groups; and nitro groups.

[0072] Of these, R 2 It is preferably a substituted or unsubstituted C1-C18 alkyl group, more preferably a methyl group, ethyl group, propyl group, isopropyl group, hexyl group, octyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, octadecyl group, benzyl group, hydroxymethyl group, or 2-hydroxyethyl group, even more preferably a methyl group, ethyl group, benzyl group, or 2-hydroxyethyl group, particularly preferably a methyl group or benzyl group, and most preferably a methyl group. In another embodiment, R 2 It is preferably a C1-C10 alkyl group substituted with an aryl group having 6-20 carbon atoms, more preferably a C1-C5 alkyl group substituted with a phenyl group, even more preferably a benzyl group or a phenylethyl group, and particularly preferably a benzyl group.

[0073] The aforementioned X is a halide ion (fluoride ion, chloride ion, bromide ion, iodide ion, etc.), hydroxide ion, organic sulfonate ion (methanesulfonate ion, p-toluenesulfonate ion, etc.), tetrafluoroborate, hexafluorophosphate, etc. Of these, X is preferably a halide ion, and more preferably a chloride ion or bromide ion.

[0074] Specific examples of ammonium salts having alkyl groups with 5 to 30 carbon atoms include: ammonium salts having a hexyl group such as hexyltrimethylammonium bromide; ammonium salts having a heptyl group such as tetraheptylammonium bromide; ammonium salts having an octyl group such as octyltrimethylammonium chloride and octyldimethylbenzylammonium chloride; ammonium salts having a decyl group such as decyltrimethylammonium chloride and decyldimethylbenzylammonium chloride; and ammonium salts having a dodecyl group such as dodecyltrimethylammonium chloride, dodecyltrimethylammonium bromide, dodecylethyldimethylammonium chloride, dodecylethyldimethylammonium bromide, benzyldodecyldimethylammonium chloride, benzyldodecyldimethylammonium bromide, toridodecylmethylammonium chloride, and toridodecylmethylammonium bromide. Examples of ammonium salts include: ammonium salts having a tetradecyl group such as tetradecyltrimethylammonium bromide and benzyldimethyltetradecylammonium chloride; ammonium salts having a hexadecyl group such as hexadecyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium p-toluenesulfonate, hexadecyltrimethylammonium hydroxide, ethylhexadecyldimethylammonium chloride, ethylhexadecyldimethylammonium bromide, and benzyldimethylhexadecylammonium chloride; and ammonium salts having an octadecyl group such as trimethyloctadecylammonium chloride, trimethyloctadecylammonium bromide, dimethyldioctadecylammonium chloride, dimethyldioctadecylammonium bromide, and benzyldimethyloctadecylammonium chloride.

[0075] Specific examples of ammonium salts having substituted or unsubstituted alkyl(poly)heteroalkylene groups include trimethylpropyldi(oxyethylene)ammonium chloride and trimethylpropyloxyethylenethioethyleneammonium chloride.

[0076] Specific examples of ammonium salts having substituted or unsubstituted aryl(poly)heteroalkylene groups include trimethyl-2-{2-[4-(1,1,3,3-tetramethylbutyl)phenoxy]ethoxy}ethylammonium chloride, benzyldimethyl-2-{2-[4-(1,1,3,3-tetramethylbutyl)phenoxy]ethoxy}ethylammonium chloride (benzethonium chloride), and benzyldimethylphenyldi(oxyethylene)ammonium chloride.

[0077] Specific examples of ammonium salts having the group represented by formula (2) include the compounds represented by the following structure.

[0078] [ka]

[0079] Heteroaryl salts having an alkyl group with 5 to 30 carbon atoms are not particularly limited, but examples include salts of heteroaryl cations in which at least one nitrogen atom of a substituted or unsubstituted nitrogen atom-containing heteroaryl ring is bonded to an alkyl group with 5 to 30 carbon atoms.

[0080] The nitrogen atom-containing heteroaryl ring is not particularly limited, but examples include rings such as imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, pyridine, pyrazine, pyridazine, pyrimidine, quinoline, and isoquinoline.

[0081] Examples of substituents when a nitrogen atom-containing heteroaryl ring has substituents include C1-C4 alkyl groups such as methyl, ethyl, propyl, and isopropyl groups; C6-C20 aryl groups such as phenyl and naphthyl groups; C1-C6 alkoxy groups such as methoxy, ethoxy, and propyloxy groups; hydroxyl groups; cyano groups; and nitro groups.

[0082] The alkyl group having 5 to 30 carbon atoms is not particularly limited, but examples include pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, and eicosyl groups.

[0083] Of these, the alkyl group having 5 to 30 carbon atoms is preferably an alkyl group having 6 to 20 carbon atoms, more preferably an alkyl group having 8 to 18 carbon atoms, even more preferably an octyl group, decyl group, dodecyl group, tetradecyl group, hexadecyl group, or octadecyl group, particularly preferably a decyl group, dodecyl group, tetradecyl group, hexadecyl group, or octadecyl group, and most preferably a tetradecyl group, hexadecyl group, or octadecyl group.

[0084] The counter anions of heteroaryl cations having an alkyl group with 5 to 30 carbon atoms are not particularly limited, but examples include halide ions such as fluoride ions, chloride ions, bromide ions, and iodide ions; hydroxide ions; organic sulfonate ions such as methanesulfonate ions and p-toluenesulfonate ions; tetrafluoroborates; and hexafluorophosphates. Of these, the counter anions are preferably halide ions, and more preferably chloride ions and bromide ions.

[0085] Specific examples of heteroaryl salts having alkyl groups with 5 to 30 carbon atoms include 1-methyl-3-hexylimidazolium chloride, 1-octyl-3-methylimidazolium chloride, 1-octyl-3-methylimidazolium bromide, 1-octyl-3-methylimidazolium tetrafluoroborate, 1-decyl-3-methylimidazolium chloride, 1-decyl-3-methylimidazolium bromide, 1-decyl-3-methylimidazolium tetrafluoroborate, 1-dodecyl-3-methylimidazolium chloride, and 1-dodecyl Imidazolium salts such as 3-methylimidazolium bromide, 1-tetradecyl-3-methylimidazolium chloride, 1-tetradecyl-3-methylimidazolium bromide, 1-hexadecyl-3-methylimidazolium chloride, 1-hexadecyl-3-methylimidazolium bromide, 1-octadecyl-3-methylimidazolium chloride, 1-octadecyl-3-methylimidazolium bromide; 3-dodecyloxazolium chloride, 3-dodecyloxazolium bromide, 3-tetradecyloxazolium chloride, 3-hex Oxazolium salts such as sadecyloxazolium chloride; thiazolium salts such as 3-dodecylthiazolium chloride, 3-dodecylthiazolium bromide, 3-dodecyl-4-methylthiazolium chloride, 3-tetradecylthiazolium chloride, 3-hexadecylthiazolium chloride; 1-hexylpyridinium chloride, 1-octylpyridinium chloride, 1-decylpyridinium chloride, 1-dodecylpyridinium chloride, 1-dodecylpyridinium bromide, 1-tetradecylpyridinium chloride, 1-tetradecylpyridinium Pyridinium salts such as lysinium bromide, 1-hexadecylpyridinium chloride, 1-hexadecylpyridinium bromide, 1-octadecylpyridinium chloride, 1-octadecylpyridinium bromide; pyrimidinium salts such as 1-hexylpyridinium chloride, 1-hexylpyridinium hexafluorophosphate, 1-octylpyridinium chloride, 1-decylpyridinium chloride, 1-dodecylpyridinium chloride, 1-tetradecylpyridinium chloride, 1-hexadecylpyridinium chloride;Examples include quinolinium salts such as dodecylquinolinium chloride, dodecylquinolinium bromide, tetradecylquinolinium chloride, and hexadecylquinolinium chloride; and isoquinolinium salts such as dodecylisoquinolinium chloride, dodecylisoquinolinium bromide, tetradecylisoquinolinium chloride, and hexadecylisoquinolinium chloride. Furthermore, these may also be used as hydrates.

[0086] Of these, (C) metal tungsten corrosion inhibitors are pyridinium salts having alkyl groups with 5 to 30 carbon atoms, and ammonium salts represented by formula (1) (where R 1 R is an alkyl group having 6 to 20 carbon atoms. 2 (where R is a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms), preferably an ammonium salt having a substituted or unsubstituted aryl(poly)heteroalkylene group, and from the viewpoint of a high etching rate of WO3, a pyridinium salt having an alkyl group having 14 to 20 carbon atoms, or an ammonium salt represented by formula (1) (where R is a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms) is preferred substituted or unsubstituted alkyl group having 14 to 20 carbon atoms 1 R is an alkyl group having 14 to 20 carbon atoms. 2It is more preferably an ammonium salt having a substituted or unsubstituted C1-C18 alkyl group, 1-tetradecylpyridinium salt, 1-hexadecylpyridinium salt, 1-octadecylpyridinium salt, tetradecyltrimethylammonium salt, hexadecyltrimethylammonium salt, octadecyltrimethylammonium salt, tetradecyldimethylbenzylammonium salt, hexadecyldimethylbenzylammonium salt, octadecyldimethylbenzylammonium salt, trimethyl-2-{2-[4-(1,1,3,3-tetramethylbutyl)phenoxy] It is more preferably ethoxyethylammonium chloride, benzyldimethyl-2-{2-[4-(1,1,3,3-tetramethylbutyl)phenoxy]ethoxy}ethylammonium chloride (benzethonium chloride), and particularly preferably 1-tetradecylpyridinium salt, 1-hexadecylpyridinium salt, 1-octadecylpyridinium salt, tetradecyltrimethylammonium salt, hexadecyltrimethylammonium salt, octadecyltrimethylammonium salt, tetradecyldimethylbenzylammonium salt, hexadecyldimethylbenzylammonium salt, or octadecyldimethylbenzylammonium salt.

[0087] Furthermore, the above-mentioned (C) metallic tungsten corrosion inhibitor may be used alone or in combination of two or more types. That is, in one preferred embodiment, the (C) metallic tungsten corrosion inhibitor is a pyridinium salt having an alkyl group with 5 to 30 carbon atoms, an ammonium salt represented by formula (1) (where R is high from the viewpoint of a high WO3 / W etching selectivity ratio), etc. 1 R is an alkyl group having 6 to 20 carbon atoms. 2 Preferably, it contains at least one selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms, and an ammonium salt having a substituted or unsubstituted aryl(poly)heteroalkylene group, and from the viewpoint of a high etching rate of WO3, a pyridinium salt having an alkyl group having 14 to 20 carbon atoms, an ammonium salt represented by formula (1) (where R is a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms), and a pyridinium salt having an alkyl group having 14 to 20 carbon atoms, and an ammonium salt represented by formula (1) (where R is a substituted or unsubstituted alkyl group having 1 to 18 carbon atoms). 1R is an alkyl group having 14 to 20 carbon atoms. 2 It is more preferably at least one selected from the group consisting of ammonium salts having a substituted or unsubstituted C1-C18 alkyl group and a substituted or unsubstituted phenyl(poly)oxyalkylene group, such as 1-tetradecylpyridinium salt, 1-hexadecylpyridinium salt, 1-octadecylpyridinium salt, tetradecyltrimethylammonium salt, hexadecyltrimethylammonium salt, octadecyltrimethylammonium salt, tetradecyldimethylbenzylammonium salt, hexadecyldimethylbenzylammonium salt, octadecyldimethylbenzylammonium salt, and trimethyl-2-{2-[4-(1,1,3,3-tetramethylbutyl)phenoxy]ethoxy}ethylammonium It is more preferable to include at least one selected from the group consisting of nium chloride and benzyldimethyl-2-{2-[4-(1,1,3,3-tetramethylbutyl)phenoxy]ethoxy}ethylammonium chloride (benzethonium chloride), and even more preferable to include at least one selected from the group consisting of 1-tetradecylpyridinium salt, 1-hexadecylpyridinium salt, 1-octadecylpyridinium salt, tetradecyltrimethylammonium salt, hexadecyltrimethylammonium salt, octadecyltrimethylammonium salt, tetradecyldimethylbenzylammonium salt, hexadecyldimethylbenzylammonium salt, and octadecyldimethylbenzylammonium salt.

[0088] (C) The addition rate of the metallic tungsten corrosion inhibitor is 0.0001 to 5% by mass, preferably 0.001 to 1% by mass, more preferably 0.003 to 0.5% by mass, and even more preferably 0.004 to 0.08% by mass, based on the total mass of the semiconductor substrate cleaning composition. (C) When the addition rate of the metallic tungsten corrosion inhibitor is within the above range, it is preferable from the viewpoint that the etching rate of tungsten can be reduced.

[0089] [(D) Tungsten oxide etching accelerator] (D) The tungsten oxide etching accelerator has the function of accelerating the etching of tungsten oxide.

[0090] The (D) tungsten oxide etching accelerator is not particularly limited, but examples include hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, 10-camphorsulfonic acid, and salts thereof.

[0091] In this case, examples of the salt include ammonium salts such as ammonium chloride, ammonium bromide, ammonium iodide, ammonium sulfate, and ammonium nitrate; and alkylammonium salts such as methylamine hydrochloride, dimethylamine hydrochloride, dimethylamine hydrobromide, and methylamine sulfate. Of these, the salt is preferably an ammonium salt.

[0092] Of the above, (D) the tungsten oxide etching accelerator is preferably hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and salts thereof; more preferably hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and ammonium salts thereof; even more preferably hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, ammonium sulfate, ammonium nitrate, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid; particularly preferably hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid, even more preferably hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, and methanesulfonic acid; and most preferably sulfuric acid and nitric acid.

[0093] The above-mentioned (D) tungsten oxide etching accelerator may be used alone or in combination of two or more. That is, in a preferred embodiment, the (D) tungsten oxide etching accelerator preferably contains at least one selected from the group consisting of hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, 10-camphorsulfonic acid, and salts thereof, and is preferably hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, ammonium chloride, ammonium bromide, ammonium iodide, ammonium sulfate, ammonium nitrate, methanesulfonic acid, trifluoromethanesulfonic acid It is more preferable to include at least one selected from the group consisting of benzoic acid, benzenesulfonic acid, p-toluenesulfonic acid, and 10-camphorsulfonic acid; it is even more preferable to include at least one selected from hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, and p-toluenesulfonic acid; it is particularly preferable to include at least one selected from hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, and nitric acid; and it is most preferable to include at least one of sulfuric acid and nitric acid.

[0094] (D) The addition rate of the tungsten oxide etching accelerator is preferably 0.01 to 20% by mass, more preferably 0.03 to 10% by mass, even more preferably 0.05 to 8% by mass, particularly preferably 0.1 to 3% by mass, and most preferably 0.1 to 0.8% by mass, based on the total mass of the semiconductor substrate cleaning composition. (D) When the addition rate of the tungsten oxide etching accelerator is within the above range, it is preferable because the removal rate of tungsten oxide can be increased while maintaining the Ti / W etching selectivity ratio.

[0095] [pH adjuster] The semiconductor substrate cleaning composition may contain a pH adjuster as needed. As the pH adjuster, for example, acids and alkalis other than (A) the oxidizing agent, (B) the fluorine compound, and (D) the tungsten oxide etching accelerator can be used. As the acid, organic acids and inorganic acids can be used. As the alkali, organic alkalis and inorganic alkalis can be used. Ammonia is preferred as the pH adjuster.

[0096] [solvent] The semiconductor substrate cleaning composition preferably contains a solvent. The solvent has functions such as uniformly dispersing each component contained in the semiconductor substrate cleaning composition and diluting it.

[0097] Examples of the aforementioned solvent include water and organic solvents.

[0098] The water is not particularly limited, but it is preferably water from which metal ions, organic impurities, and particulate matter have been removed by distillation, ion exchange treatment, filtration treatment, or various adsorption treatments. Pure water is more preferable, and ultrapure water is particularly preferable.

[0099] The aforementioned organic solvents are not particularly limited, but include alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and tert-butanol; polyhydric alcohols such as ethylene glycol, propylene glycol, neopentyl glycol, 1,2-hexanediol, 1,6-hexanediol, 2-ethylhexane-1,3-diol, and glycerin; and glycol ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monoethyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, tripropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, and propylene glycol phenyl ether.

[0100] Of the above, water is more preferably used as the solvent. The solvent may be used alone or in combination of two or more types.

[0101] The solvent, particularly water, is preferably added at a concentration of 50% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and especially preferably 95% by mass or more, relative to the total mass of the semiconductor substrate cleaning composition. A solvent addition rate of 50% by mass or more is preferable from the viewpoint of being able to suitably control the Ti / W etching selectivity ratio and the WO3 / W etching selectivity ratio.

[0102] [Iodine scavenger] If the oxidizing agent (A) above contains an oxoacid of iodine, the semiconductor substrate cleaning composition preferably further contains an iodine scavenger.

[0103] As an iodine scavenger, there are no particular restrictions, but acetone, butanone, 2-methyl-2-butanone, 3,3-dimethyl-2-butanone, 4-hydroxy-2-butanone, 2-pentanone, 3-pentanone, 3-methyl-2-pentanone, 4-methyl-2-pentanone, 2-methyl-3-pentanone, 5-methyl-3-pentanone, 2,4-dimethyl-3-pentanone, 5-hydroxy-2-pentanone, 4-hydroxy-4-methyl-2-pentanone, 2-hexanone, 3-hexanone, 2-heptanone, 3-heptanone, 4 Examples include aliphatic ketones such as -heptanone, 5-methyl-2-heptanone, 5-methyl-3-heptanone, 2,6-dimethyl-4-heptanone, 2-octanone, 3-octanone, 4-octanone, cyclohexanone, 2,6-dimethylcyclohexanone, 2-acetylcyclohexanone, menthone, cyclopentanone, and dicyclohexylketone; aliphatic diketones such as 2,5-hexanedione, 2,4-pentanedione, and acetylacetone; and aromatic ketones such as acetophenone, 1-phenylethanone, and benzophenone. Of these, the iodine scavenger is preferably an aliphatic ketone, more preferably 4-methyl-2-pentanone, 5-methyl-3-pentanone, 2,4-dimethyl-3-pentanone, and cyclohexanone, and even more preferably 4-methyl-2-pentanone. These iodine scavengers may be used individually or in combination of two or more.

[0104] [Low dielectric constant passivator] The semiconductor substrate cleaning composition may further contain a low dielectric constant passivator. The low dielectric constant passivator has the function of preventing or suppressing etching of low dielectric constant films, such as insulating films.

[0105] Low dielectric constant passivating agents are not particularly limited, but include boric acid; borates such as ammonium pentaborate and sodium tetraborate; and carboxylic acids such as 3-hydroxy-2-naphthoic acid, malonic acid, and iminodiacetic acid.

[0106] These low dielectric constant passivators may be used individually or in combination of two or more types.

[0107] The addition rate of the low dielectric constant passivator is preferably 0.01 to 2% by mass, more preferably 0.02 to 1% by mass, and even more preferably 0.03 to 0.5% by mass, based on the total mass of the semiconductor substrate cleaning composition.

[0108] [Additives] The semiconductor substrate cleaning composition may further contain additives. Examples of such additives include surfactants, chelating agents, defoaming agents, and silicon-containing compounds.

[0109] [Physical properties of compositions for cleaning semiconductor substrates] The pH of the semiconductor substrate cleaning composition is preferably 0.1 to 5.0, more preferably 0.1 to 3, even more preferably 0.2 to 2, particularly preferably 0.3 to 1.8, and especially preferably 0.4 to 1.5, from the viewpoint of increasing the Ti / W etching selectivity ratio.

[0110] The etching rate of tungsten oxide in the semiconductor substrate cleaning composition is preferably 2.0 Å / min or higher, more preferably 2.2 Å / min or higher, even more preferably 2.5 Å / min or higher, particularly preferably 3.0 to 50 Å / min, and most preferably 3.5 to 30 Å / min. An etching rate of tungsten oxide of 2.0 Å / min or higher is preferable from the viewpoint of shortening the time required for the selective etching process of titanium-titanium alloys and increasing the WO3 / W etching selectivity ratio. Note that the etching rate of tungsten oxide refers to the value measured by the method of the example.

[0111] The etching rate of metallic tungsten in the semiconductor substrate cleaning composition is preferably 7.5 Å / min or less, more preferably 5.0 Å / min or less, even more preferably 4.5 Å / min or less, particularly preferably 4.0 Å / min or less, and most preferably 0.1 to 3.5 Å / min. An etching rate of metallic tungsten of 7.5 Å / min or less is preferable because it increases the Ti / W etching selectivity ratio. Note that the etching rate of metallic tungsten refers to the value measured by the method of the example.

[0112] The etching rate of titanium and titanium alloys in the semiconductor substrate cleaning composition is preferably 7 Å / min or higher, more preferably 9 Å / min or higher, even more preferably 15 Å / min or higher, even more preferably 30 Å / min or higher, particularly preferably 50 Å / min or higher, and most preferably 80 Å / min or higher. An etching rate of 7 Å / min or higher for titanium alloys is preferable because it increases the Ti / W etching selectivity ratio. Note that the etching rates of titanium and titanium alloys refer to the values ​​measured by the method of the example.

[0113] The etching rate of the insulating layer material of the semiconductor substrate cleaning composition is preferably 3.0 Å / min or less, more preferably 1.0 Å / min or less, even more preferably 0.7 Å / min or less, particularly preferably 0.6 Å / min or less, and most preferably 0.5 Å / min or less. An etching rate of 3.0 Å / min or less is preferable because it maintains the shape of the semiconductor substrate and improves its performance as a semiconductor device. The insulating layer material is not particularly limited, but examples include silicon dioxide (e.g., th-Ox). The etching rate of the insulating layer material refers to the value measured by the method of the example.

[0114] The Ti / W etching selectivity ratio (etching rate of titanium and titanium alloys / etching rate of metallic tungsten) of the semiconductor substrate cleaning composition is preferably 5 or higher, more preferably 10 or higher, even more preferably 20 or higher, particularly preferably 30 or higher, and most preferably 50 or higher. A Ti / W etching selectivity ratio of 5 or higher is preferable because it allows for the construction of a desired etching manufacturing process.

[0115] The WO3 / W etching selectivity ratio (etching rate of tungsten oxide / etching rate of metallic tungsten) of the semiconductor substrate cleaning composition is preferably 0.5 or higher, more preferably 0.8 or higher, even more preferably 1.0 or higher, particularly preferably 1.5 to 15, and most preferably 3 to 10. A WO3 / W etching selectivity ratio of 0.5 or higher is preferable because it increases productivity. In other words, according to one preferred embodiment, a semiconductor substrate cleaning composition is provided for etching tungsten oxide while suppressing the etching of metallic tungsten.

[0116] <Method for cleaning semiconductor substrates> According to one embodiment of the present invention, a method for cleaning a semiconductor substrate using the above-described semiconductor substrate cleaning composition is provided. The cleaning method includes a step of bringing a semiconductor substrate having a layer containing metallic tungsten, a layer containing at least one of titanium and a titanium alloy, and a layer containing tungsten oxide into contact with the above-described semiconductor substrate cleaning composition to remove at least a portion of the layer containing at least one of titanium and a titanium alloy and the layer containing tungsten oxide.

[0117] The configuration of a semiconductor substrate before cleaning may vary depending on its application. For example, when a semiconductor substrate is used in a memory element, it may have a structure in which an insulating film, a barrier film made of titanium or titanium nitride, and a metallic tungsten film are stacked in that order on a silicon substrate having recesses. In this case, the surface of the metallic tungsten film may have a tungsten oxide film formed by the oxidation of metallic tungsten. This tungsten oxide film is formed, for example, by oxidation by oxygen in the atmosphere or oxidation by ashing. In such an embodiment, the layer containing metallic tungsten corresponds to the metallic tungsten film, the layer containing titanium and at least one titanium alloy corresponds to the barrier film, and the layer containing tungsten oxide corresponds to the tungsten oxide film.

[0118] Furthermore, when the semiconductor substrate is used in a logic element, the silicon substrate having a transistor layer may include an etched insulating film, a hard mask made of patterned titanium or titanium nitride, and metallic tungsten formed at the bottom of the recesses in the insulating film formed by etching. In this case, the surface of the metallic tungsten may have a tungsten oxide film formed by the oxidation of the metallic tungsten. This tungsten oxide film is formed, for example, by oxidation by oxygen in the atmosphere or by ashing. In such an embodiment, the layer containing metallic tungsten corresponds to the metallic tungsten formed at the bottom of the recesses in the insulating film formed by etching, the layer containing at least one of titanium and a titanium alloy corresponds to the hard mask, and the layer containing tungsten oxide corresponds to the tungsten oxide film.

[0119] Furthermore, the configuration of the semiconductor substrate before cleaning may be modified by appropriately referring to known technologies.

[0120] By bringing the semiconductor substrate cleaning composition described above into contact with the semiconductor substrate before cleaning, at least a portion of the layer containing at least one of titanium and titanium alloy, and the layer containing tungsten oxide can be removed. This allows for selective etching of titanium and titanium alloy while removing tungsten oxide.

[0121] The method of contact between the semiconductor substrate and the semiconductor substrate cleaning composition is not particularly limited, and known techniques may be used as appropriate. Specifically, the semiconductor substrate may be immersed in the semiconductor substrate cleaning composition, or the semiconductor substrate cleaning composition may be sprayed onto the semiconductor substrate or dropped (e.g., single-wafer spin treatment). In this case, the immersion may be repeated two or more times, the spraying may be repeated two or more times, the dropping may be repeated two or more times, or immersion, spraying, and dropping may be combined.

[0122] The contact temperature is not particularly limited, but is preferably 0 to 90°C, more preferably 15 to 80°C, and even more preferably 20 to 70°C.

[0123] The contact time is not particularly limited, but is preferably 10 seconds to 3 hours, more preferably 10 seconds to 1 hour, even more preferably 10 seconds to 45 minutes, and particularly preferably 20 seconds to 5 minutes.

[0124] <Manufacturing method for semiconductor substrates> Furthermore, according to one embodiment of the present invention, a method for manufacturing a semiconductor substrate using the above-described semiconductor substrate cleaning composition is provided. The manufacturing method includes a step of bringing a semiconductor substrate having a layer containing metallic tungsten, a layer containing at least one of titanium and a titanium alloy, and a layer containing tungsten oxide into contact with the above-described semiconductor substrate cleaning composition to remove at least a portion of the layer containing at least one of titanium and a titanium alloy and the layer containing tungsten oxide.

[0125] The specific method for the above-mentioned process is the same as the semiconductor substrate cleaning method described above.

[0126] The semiconductor substrates manufactured in this way can be used as materials for semiconductor devices, enabling the production of high-performance semiconductor devices. [Examples]

[0127] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[0128] [Example 1] A semiconductor substrate cleaning composition was prepared by adding (A) iodic acid (HIO3), an oxidizing agent, (B) hydrogen fluoride (HF), a fluorine compound, (C) 1-dodecylpyridinium chloride (DPC), a metallic tungsten corrosion inhibitor, and (D) sulfuric acid, a tungsten oxide etching accelerator, to pure water and stirring. The addition rates of iodic acid, hydrogen fluoride, 1-dodecylpyridinium chloride (DPC), and sulfuric acid were 0.018% by mass, 0.05% by mass, 0.005% by mass, and 0.5% by mass, respectively, based on the total mass of the semiconductor substrate cleaning composition. The pH of the semiconductor substrate cleaning composition was 1.3. The pH of the pretreatment agent at 23°C was measured using a benchtop pH meter (F-71) and pH electrode (9615S-10D) manufactured by Horiba, Ltd.

[0129] [Examples 2-19 and Comparative Examples 1-8] A semiconductor substrate cleaning composition was manufactured by changing the added components as shown in Tables 1 and 2 below.

[0130] [Table 1]

[0131] [Table 2]

[0132] The DPC, CPC, DMIC, CTAB, HTMAB, and BZC used in the examples and comparative examples have the following structures.

[0133] [ka]

[0134] [evaluation] The etching rates of the semiconductor substrate cleaning compositions prepared in Examples 1-19 and Comparative Examples 1-8 against tungsten oxide films, metallic tungsten films, titanium nitride films, and silicon oxide (th-Ox) films were evaluated. The etching selectivity of tungsten oxide (WO3) against metallic tungsten (W) (WO3 / W etching selectivity ratio) and titanium nitride (TiN) against metallic tungsten (W) (TiN / W etching selectivity ratio) were also evaluated.

[0135] (Etching rate of tungsten oxide (WO3) film) Tungsten oxide (WO3) was deposited on a silicon wafer by physical vapor deposition until it reached a thickness of 3000 Å, and a 1cm x 1cm (immersion treatment area: 1cm) was created. 2 By cutting the material to the size of ), tungsten oxide film samples were prepared.

[0136] In Examples 1-19 and Comparative Examples 1-8, 10 g of the semiconductor substrate cleaning composition was used to immerse a tungsten oxide film sample in a predetermined treatment temperature for 10 minutes. After immersion treatment, the semiconductor substrate cleaning composition was diluted 10 to 20 times with a 1% by mass aqueous nitric acid solution to prepare a measurement sample. The tungsten concentration in the measurement sample was measured using an ICP emission spectrometer (ICP-OES) Avio200 (manufactured by PerkinElmer).

[0137] In this process, the samples for creating the calibration curve were prepared using the following method: Tungsten standard solution (tungsten concentration: 1000 ppm, manufactured by Fujifilm Wako Co., Ltd.) was diluted with a 1% by mass aqueous solution of nitric acid to prepare calibration curve samples with tungsten concentrations of 25 ppb, 12.5 ppb, and 2.5 ppb.

[0138] The tungsten concentration before dilution was calculated from the tungsten concentration of the measurement sample, which was determined using a sample for calibration curve creation. The etching amount of the tungsten oxide film was then calculated by substituting the tungsten concentration before dilution and the amount of semiconductor substrate cleaning composition used (the amount of the measurement sample before dilution) into the following formula.

[0139]

number

[0140] In the above formula, 231.84 (g / mol) is the molecular weight of tungsten oxide (WO3), and 7.16 (g / cm³) is the molecular weight of tungsten oxide (WO3). 3 ) is the density of tungsten oxide, 1 cm 2 is the immersion treatment area of ​​the tungsten oxide film sample, and 183.84 (g / mol) is the molecular weight of metallic tungsten (W).

[0141] The etching rate (ER) of the tungsten oxide film was calculated by dividing the calculated etching amount of the tungsten oxide film by the immersion time using the semiconductor substrate cleaning composition. The results are shown in Table 3 below.

[0142] (Etching rate of metallic tungsten (W) film) Tungsten (W) was deposited on a silicon wafer by physical vapor deposition until it reached a thickness of 1000 Å, and a 1 cm x 1 cm (immersion treatment area: 1 cm) was created. 2 Metal tungsten film samples were prepared by cutting them to the size of ( ).

[0143] Except for using a metallic tungsten film sample and having an immersion treatment time of 2 minutes, the measurement sample was prepared in the same manner as the method for measuring the etching rate of tungsten oxide films, and the tungsten concentration in the measurement sample was measured.

[0144] The tungsten concentration before dilution was calculated from the tungsten concentration of the measurement sample, which was determined using a sample for calibration curve creation. The etching amount of the metallic tungsten film was then calculated by substituting the tungsten concentration before dilution and the amount of semiconductor substrate cleaning composition used for measurement (the amount of the measurement sample before dilution) into the following formula.

[0145]

number

[0146] Note that in the above formula, 19.25 (g / cm³) 3 ) is the density of metallic tungsten, 1 cm 2 This represents the immersion treatment area of ​​the tungsten film sample.

[0147] The etching rate (ER) of the metallic tungsten film was calculated by dividing the calculated etching amount of the metallic tungsten film by the immersion time using the semiconductor substrate cleaning composition. The results are shown in Table 3 below.

[0148] (Etching rate of titanium nitride (TiN) film) Titanium nitride (TiN) was deposited on a silicon wafer using physical vapor deposition until it reached a thickness of 1000 Å, and a 2cm x 2cm (immersion treatment area: 4cm) was created. 2 Titanium nitride film samples were fabricated by cutting them to the size of [size].

[0149] The film thickness of titanium nitride film samples was measured using an X-ray fluorescence spectrometer EA1200VX (manufactured by Hitachi High-Tech).

[0150] In each of the semiconductor substrate cleaning compositions prepared in Examples 1-19 and Comparative Examples 1-8, titanium nitride film samples were immersed in 10 g of each composition at a predetermined processing temperature for a predetermined time.

[0151] The film thickness of titanium nitride film samples after immersion treatment with a semiconductor substrate cleaning composition was measured using the same method as described above.

[0152] The difference in film thickness between titanium nitride film samples before and after immersion treatment with a semiconductor substrate cleaning composition was calculated, and the etching rate (ER) of the titanium nitride film was calculated by dividing this by the immersion time with the semiconductor substrate cleaning composition. The results obtained are shown in Table 3 below.

[0153] (Etching rate of silicon dioxide (th-Ox) film) A silicon dioxide film is deposited on a silicon wafer by thermal oxidation until it reaches a thickness of 1000 Å, and then immersed in a 1cm x 1cm (immersion treatment area: 1cm) 2 A silicon dioxide film sample was prepared by cutting it to the size of [size].

[0154] The film thickness of silicon dioxide film samples was measured using an optical film thickness gauge, n&k1280 (manufactured by n&k Technology Co., Ltd.).

[0155] A silicon dioxide film sample was immersed in 10 g of the semiconductor substrate cleaning composition prepared in Examples 1-19 and Comparative Examples 1-8 at a predetermined processing temperature for 30 minutes.

[0156] The film thickness of the silicon dioxide film-formed sample after immersion treatment was measured using the same method as described above.

[0157] The difference in film thickness between silicon oxide film samples before and after processing was calculated, and the etching rate (ER) of the silicon oxide film was calculated by dividing this by the immersion time using the semiconductor substrate cleaning composition. The results are shown in Table 3 below.

[0158] [WO3 / W etching selectivity ratio] The WO3 / W etching selectivity ratio was calculated by dividing the etching rate (ER) of the tungsten oxide film of the semiconductor substrate cleaning compositions prepared in Examples 1-19 and Comparative Examples 1-8 by the etching rate (ER) of the metallic tungsten film. The results are shown in Table 3 below.

[0159] [TiN / W etching selectivity ratio] The TiN / W etching selectivity ratio was calculated by dividing the etching rate (ER) of the titanium nitride film of the semiconductor substrate cleaning compositions prepared in Examples 1-19 and Comparative Examples 1-8 by the etching rate (ER) of the metallic tungsten film. The results are shown in Table 3 below.

[0160] [Table 3]

[0161] The results in Table 3 show that the semiconductor cleaning compositions of Examples 1 to 19 have a high TiN / W etching selectivity ratio. Furthermore, the semiconductor cleaning compositions of Examples 1 to 19 have a high etching rate for tungsten oxide (WO3), which means that the processing time for removing tungsten oxide can be shortened. [Explanation of Symbols]

[0162] 10. Semiconductor substrate for memory elements (before cleaning) 11 Silicon substrate having recesses 12 Insulating film 13 Barrier film 14 Metallic tungsten film 15 Tungsten Oxide 20. Semiconductor substrate for memory elements (after cleaning) 21 Silicon substrate having recesses 22 Insulating film 23 Etched barrier film 24 Metallic tungsten film 30. Semiconductor substrate for logic elements (before cleaning) 32 Insulating film 33 Hard Mask 34 Metal Tungsten Plugs 35 Tungsten Oxide 40. Semiconductor substrate for logic elements (after cleaning) 42 Insulating film 44 Metal Tungsten Plugs

Claims

1. A composition for cleaning semiconductor substrates comprising (A) an oxidizing agent, (B) a fluorine compound, (C) a metallic tungsten corrosion inhibitor, and (D) a tungsten oxide etching accelerator, The oxidizing agent (A) comprises at least one selected from the group consisting of halogen oxoacids and their salts, The addition rate of the oxidizing agent (A) is 0.0001 to 10% by mass relative to the total mass of the semiconductor substrate cleaning composition. The addition rate of the fluorine compound (B) is 0.005 to 10% by mass relative to the total mass of the semiconductor substrate cleaning composition. A semiconductor substrate cleaning composition wherein the addition rate of the (C) metallic tungsten corrosion inhibitor is 0.0001 to 5% by mass relative to the total mass of the semiconductor substrate cleaning composition.

2. The semiconductor substrate cleaning composition according to claim 1, wherein the addition rate of (D) tungsten oxide etching accelerator is 0.01 to 20% by mass with respect to the total mass of the semiconductor substrate cleaning composition.

3. The semiconductor substrate cleaning composition according to claim 1 or 2, wherein the oxidizing agent (A) contains iodic acid.

4. The (B) fluorine compound is hydrogen fluoride (HF), tetrafluoroboric acid (HBF ４ ), hexafluorosilicic acid (H ２ SiF ６ ), hexafluorozirconic acid (H ２ ZrF ６ ), hexafluorotitanic acid (H ２ TiF ６ ), hexafluorophosphoric acid (HPF ６ ), hexafluoroaluminic acid (H ２ AlF ６ ), hexafluorogermanic acid (H ２ GeF ６ ), and the semiconductor substrate cleaning composition according to any one of claims 1 to 3, comprising at least one selected from the group consisting of these salts.

5. The aforementioned (C) metal tungsten corrosion inhibitor is given by the following formula (1): 【Chemistry 1】 (In the above formula (1), R １ This includes alkyl groups having 5 to 30 carbon atoms, substituted or unsubstituted alkyl (poly)heteroalkylene groups, substituted or unsubstituted aryl (poly)heteroalkylene groups, and the following formula (2): 【Chemistry 2】 (In the above formula, Cy is a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted heterocycloalkyl group having 2 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 15 carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 15 carbon atoms. A is an alkylene with 1 to 5 carbon atoms, independently of each other. r is either 0 or 1, Z is given by the following formula: 【Transformation 3】 It is one of the following. It is a base represented by, R ２ These are, independently, a substituted or unsubstituted C1-C18 alkyl group and a substituted or unsubstituted C6-C20 aryl group. X is a halide ion, hydroxide ion, organic sulfonate ion, tetrafluoroborate, or hexafluorophosphate. A semiconductor substrate cleaning composition according to any one of claims 1 to 4, comprising at least one selected from the group consisting of an ammonium salt represented by and a heteroaryl salt having an alkyl group having 5 to 30 carbon atoms.

6. The semiconductor substrate cleaning composition according to any one of claims 1 to 5, wherein the (D) tungsten oxide etching accelerator comprises at least one selected from the group consisting of hydrogen chloride, hydrogen bromide, hydrogen iodide, sulfuric acid, nitric acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, 10-camphorsulfonic acid, and salts thereof.

7. The semiconductor substrate cleaning composition according to claim 6, wherein the salt is an ammonium salt.

8. A semiconductor substrate cleaning composition according to any one of claims 1 to 7, wherein the pH is 0.1 to 5.

0.

9. A semiconductor substrate cleaning composition according to any one of claims 1 to 8, which is a semiconductor substrate cleaning composition for etching tungsten oxide while suppressing the etching of metallic tungsten.

10. A method for cleaning a semiconductor substrate, comprising the step of contacting a semiconductor substrate having a layer containing metallic tungsten, a layer containing at least one of titanium and a titanium alloy, and a layer containing tungsten oxide with a semiconductor substrate cleaning composition according to any one of claims 1 to 9 to remove at least a portion of the layer containing at least one of titanium and a titanium alloy and the layer containing tungsten oxide.

11. A method for manufacturing a semiconductor substrate, comprising the step of contacting a semiconductor substrate having a layer containing metallic tungsten, a layer containing at least one of titanium and a titanium alloy, and a layer containing tungsten oxide with a semiconductor substrate cleaning composition according to any one of claims 1 to 9 to remove at least a portion of the layer containing at least one of titanium and a titanium alloy and the layer containing tungsten oxide.

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