Composition for forming organic film, method for forming organic film, and method for forming pattern

Abstract

The invention relates to a composition for forming an organic film, an organic film forming method, and a pattern forming method. The present invention addresses the problem of providing: a composition for forming an organic film, which has excellent film-forming properties (in-plane uniformity) and landfill characteristics on a substrate (wafer) and in which bumps during an EBR step are suppressed; a method for forming an organic film using the composition; and a method for forming a pattern using the composition. [Solution] A composition for forming an organic film, which is characterized by containing (A) a polymer having a repeating unit represented by general formula (1), (B) a resin for forming an organic film, and (C) a solvent. In general formula (1), R represents a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.

Description

Technical Field

[0001] The present invention relates to an organic film forming composition, an organic film forming method using the composition, and a pattern forming method using the composition. Background Art

[0002] In recent years, with the high integration and high speed of semiconductor elements, the demand for regular and fine patterns has gradually increased. Among them, in the field of photolithography using light exposure, which is currently used as a general technology, people have developed various technologies on the light source used and how to perform more fine and high-precision pattern processing.

[0003] As for the light source for photolithography used in the formation of resist patterns, light exposure using the g-line (436nm) or i-line (365nm) of a mercury lamp as the light source has been widely used in parts with low integration. On the other hand, in parts with high integration and requiring miniaturization, photolithography using shorter wavelengths of KrF excimer lasers (248nm) and ArF excimer lasers (193nm) has also been put into practical use. In the most advanced generation that requires further miniaturization, photolithography using extreme ultraviolet rays (EUV, 13.5nm) has also become practical.

[0004] As the thinning of the resist pattern progresses, it is well known that in the single-layer resist method used as a typical resist pattern forming method, the ratio of the pattern height to the pattern line width (aspect ratio) becomes larger, and the pattern collapses due to the surface tension of the developer during development. Therefore, if a pattern with a high aspect ratio is to be formed on a high-height substrate, a multilayer resist method in which films having different dry etching characteristics are stacked and patterned is known to be excellent, and a two-layer resist method (Patent Document 1) combining a photoresist layer (resist upper film) obtained by using a silicon-containing photosensitive polymer and a resist lower film obtained by using an organic polymer having carbon, hydrogen and oxygen as main constituent elements, such as a novolac polymer, has been developed, and a three-layer resist method (Patent Document 2) combining a photoresist layer obtained by using an organic photosensitive polymer used in the single-layer resist method, a resist intermediate film obtained by using a silicon polymer or a silicon CVD film, and a resist lower film obtained by using an organic polymer has been developed.

[0005] In the three-layer resist method, for example, an organic film such as novolac is uniformly formed on a substrate to be processed as a resist lower layer film, a silicon-containing resist intermediate film is formed thereon as a resist intermediate film, and a normal organic photoresist film is formed thereon as a resist upper layer film. Since the organic resist upper layer film can obtain a good etching selectivity ratio with respect to the silicon-containing resist intermediate film in dry etching performed by fluorine-based gas plasma, the resist pattern is transferred to the silicon-containing resist intermediate film by dry etching performed by fluorine-based gas plasma. According to this method, even if a resist composition is used that is difficult to form a pattern having a sufficient film thickness for directly processing a substrate to be processed, or a resist composition that has insufficient dry etching resistance when used to process a substrate, the pattern can still be transferred to a silicon-containing resist intermediate film. Subsequently, by performing pattern transfer using dry etching using oxygen-based gas plasma, a pattern of a phenolic varnish film (resist lower layer film) having sufficient dry etching resistance during processing can be obtained.

[0006] As mentioned above, many technologies for organic films are known (e.g., Patent Document 3), but with the recent progress in miniaturization, in addition to dry etching properties, the need for excellent filling properties has gradually increased. Even if the base substrate to be processed is a substrate of a complex shape or material, an organic film material is required that can be uniformly formed on it and has a filling property that can fill the necessary pattern without gaps.

[0007] When manufacturing semiconductor substrates, etc., organic films such as those described above are formed using a coating / developing device that can perform processes such as spin coating, EBR, and firing. The EBR (Edge Bead Removal) step refers to a step in which, after a film is formed on a substrate (wafer) by spin coating, a removal liquid is used to remove the film at the end of the substrate in order to prevent contamination of the substrate transport arm of the coating / developing device. As for the removal liquid used in the EBR step, there is a mixed solution of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether (30% by mass: 70% by mass), which has been widely used in the EBR step of resist upper films, silicon-containing resist intermediate films, and organic films.

[0008] The outer periphery of the organic film may become thick (bulge) due to the influence of the remover in the EBR step. In the dry etching step during substrate processing, the bulge may cause defects, so an organic film with suppressed bulge is required.

[0009] Prior art literature

[0010] Patent Literature

[0011] [Patent Document 1] Japanese Patent Application Laid-Open No. 06-118651

[0012] [Patent Document 2] Japanese Patent No. 4355943

[0013] [Patent Document 3] Japanese Patent Application Publication No. 2004-205685 Summary of the invention

[0014] [Problems to be solved by the invention]

[0015] The present invention is made in view of the above situation and aims to provide an organic film forming composition having excellent film forming properties (in-plane uniformity) and filling characteristics on a substrate (wafer) and suppressed protrusions during the EBR step, an organic film forming method using the composition, and a pattern forming method.

[0016] [Methods to solve the problem]

[0017] In order to solve the above problems, the present invention provides an organic film-forming composition comprising: (A) a polymer having a repeating unit represented by the following general formula (1), (B) an organic film-forming resin, and (C) a solvent.

[0018] [Chemistry 1]

[0019]

[0020] (In the general formula (1), R is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.)

[0021] According to such an organic film forming composition, it is possible to form an organic film which has excellent in-plane uniformity and filling characteristics and in which the formation of protrusions due to the influence of the remover in the EBR step is suppressed.

[0022] In the present invention, the polymer (A) is preferably any one or more of the following general formulas (2) to (4).

[0023] [Chemistry 2]

[0024]

[0025] (In the formula, R1 is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms and may have an ether bond. R2 is a monovalent organic group having 1 to 30 carbon atoms, and n represents the average number of repeating units and is 3 to 2,000.)

[0026] An organic film-forming composition containing such a polymer is preferred because the in-plane uniformity of the organic film after film formation is further improved.

[0027] In the present invention, the content of the polymer (A) is preferably 0.01 to 5 parts by mass based on 100 parts by mass of the organic film-forming resin (B).

[0028] The organic film-forming composition containing the polymer in such a content is preferred because the in-plane uniformity of the organic film after film formation is further improved.

[0029] Furthermore, the present invention provides an organic film forming method, which is an organic film forming method used in the manufacturing steps of a semiconductor device, characterized in that: the above-described organic film forming composition is spin-coated on a processed substrate, and the above-mentioned substrate coated with the above-mentioned organic film forming composition is heat-treated at a temperature of not less than 100°C and not more than 600°C and in a range of 10 to 600 seconds to harden it, thereby forming an organic film.

[0030] The organic film forming method of the present invention is particularly useful for filling a complex pattern on a processed substrate by spin coating, forming an organic film with excellent in-plane uniformity, and removing the organic film at the edge while suppressing bulging in the EBR step.

[0031] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0032] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0033] A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material.

[0034] A resist upper layer film is formed on the silicon-containing resist intermediate film using a resist upper layer film material composed of a photoresist composition.

[0035] forming a circuit pattern on the resist upper film,

[0036] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the silicon-containing resist intermediate film by etching.

[0037] The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0038] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0039] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0040] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0041] A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material.

[0042] forming an organic antireflection film or a close-fitting film on the aforementioned silicon-containing resist intermediate film,

[0043] On the organic antireflection film or the adhesion film, a resist upper layer film is formed using a resist upper layer film material composed of a photoresist composition,

[0044] forming a circuit pattern on the resist upper film,

[0045] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the silicon-containing resist intermediate film by etching.

[0046] The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0047] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0048] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0049] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0050] forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the aforementioned organic film,

[0051] A resist upper layer film is formed on the inorganic hard mask intermediate film using a resist upper layer film material composed of a photoresist composition,

[0052] forming a circuit pattern on the resist upper film,

[0053] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the inorganic hard mask intermediate film by etching.

[0054] The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0055] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0056] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0057] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0058] forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the aforementioned organic film,

[0059] forming an organic anti-reflection film or a bonding film on the inorganic hard mask intermediate film;

[0060] On the organic antireflection film or the adhesion film, a resist upper layer film is formed using a resist upper layer film material composed of a photoresist composition,

[0061] forming a circuit pattern on the resist upper film,

[0062] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the inorganic hard mask intermediate film by etching.

[0063] The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0064] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0065] As such, the organic film forming composition of the present invention can be ideally used in various pattern forming methods such as three-layer resist processing using a silicon-containing resist intermediate film or an inorganic hard mask intermediate film, and four-layer resist processing using an organic anti-reflective film or a bonding film in addition to these. If it is such a pattern forming method of the present invention, the circuit pattern of the resist upper layer film can be transferred to the processed body with high precision to form.

[0066] At this time, the inorganic hard mask intermediate film is preferably formed by a CVD method or an ALD method.

[0067] The pattern forming method of the present invention can form an inorganic hard mask intermediate film in the following manner, for example.

[0068] In the present invention, when forming the circuit pattern, it is preferable to form the circuit pattern by photolithography using light with a wavelength of 10 nm to 300 nm, direct drawing using an electron beam, nanoimprinting, or a combination thereof.

[0069] In the present invention, when the circuit pattern is formed, it is preferred that the circuit pattern be developed using an alkali developer or an organic solvent.

[0070] In the pattern forming method of the present invention, such a circuit pattern forming means and developing means can be preferably used.

[0071] Furthermore, the present invention preferably uses a semiconductor device substrate or a substrate obtained by forming any one of a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxide carbide film and a metal oxide nitride film on the aforementioned semiconductor device substrate as the aforementioned processed body.

[0072] At this time, silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum or an alloy thereof is preferably used as the metal constituting the aforementioned processed body.

[0073] According to the pattern forming method of the present invention, the above-mentioned workpiece can be processed and patterned.

[0074] [Effects of the Invention]

[0075] As described above, the present invention can provide an organic film forming composition having excellent film forming properties (uniformity in the plane) and filling properties on a substrate (wafer) and suppressing bulges during the EBR step. Moreover, the organic film forming composition of the present invention has excellent film forming properties and filling properties and suppresses bulges generated during the EBR step, so it is extremely useful as an organic film forming material used in multilayer resist processing such as a two-layer resist processing, a three-layer resist processing using a silicon-containing resist intermediate film or an inorganic hard mask intermediate film, or a four-layer resist processing using a silicon-containing resist intermediate film or an inorganic hard mask intermediate film and an organic anti-reflective film or a bonding film, or an organic film forming material for semiconductor device manufacturing. Furthermore, the organic film forming method of the present invention can form an organic film with suppressed bulges, so semiconductor elements can be efficiently manufactured. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] [ Figure 1 ] is an example of a graph obtained by measuring the height of ridges using a contact profiler for an organic film forming composition in which ridges are suppressed.

[0077] [ Figure 2 ] is an example of a graph obtained by measuring the height of ridges using a contact profiler in an organic film forming composition in which ridges are not suppressed.

[0078] [ Figure 3 ](A) to (F) are explanatory diagrams of an example of a pattern forming method of the present invention formed by a three-layer resist process.

[0079] [ Figure 4 ](G) to (I) are explanatory diagrams of the landfill characteristic evaluation method in the example. DETAILED DESCRIPTION

[0080] As described above, it is necessary to develop an organic film forming composition having excellent film forming properties (in-plane uniformity) and filling properties on a substrate (wafer) and suppressing protrusions during an EBR step, and an organic film forming method and a pattern forming method using the composition.

[0081] Usually, when forming an organic film, the resin and additives for forming the organic film are dissolved in an organic solvent to form a composition, and the composition is applied to a substrate on which a structure, wiring, etc. have been formed using a coating / developing device. The substrate is rotated to spread the composition, and the composition at the end is removed in the EBR step, and then the organic film is formed by firing.

[0082] It is believed that if the fluidity of the above-mentioned composition is insufficient, voids will be generated when filling holes and trenches with very high aspect ratios. At the same time, if the solubility of the organic film forming resin and additives in the remover used in the EBR step is poor, bulges will be generated on the periphery of the organic film.

[0083] The inventors of the present application have made further efforts to study and found that by blending a polymer having a specific repeating unit into an organic film-forming composition, an organic film-forming composition having excellent film-forming properties, high filling characteristics, and ridge suppression during the EBR step can be provided, thereby completing the present invention.

[0084] That is, the present invention is an organic film-forming composition comprising (A) a polymer having a repeating unit represented by the following general formula (1), (B) an organic film-forming resin, and (C) a solvent.

[0085] [Chemistry 3]

[0086]

[0087] (In the general formula (1), R is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.)

[0088] The present invention will be described in detail below, but the present invention is not limited to these.

[0089] [Organic film forming composition]

[0090] The organic film-forming composition of the present invention comprises (A) a polymer having a repeating unit represented by the following general formula (1), (B) an organic film-forming resin, and (C) a solvent.

[0091] [Chemistry 4]

[0092]

[0093] (In the general formula (1), R is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.)

[0094] In the organic film-forming composition of the present invention, the (A) polymer, the (B) organic film-forming resin, and the (C) solvent may be used alone or in combination of two or more.

[0095] Here, the "organic group" referred to in the present invention refers to a group containing at least one carbon atom, and may further contain a hydrogen atom, and may also contain a nitrogen atom, an oxygen atom, a sulfur atom, a silicon atom, a halogen atom, and the like.

[0096] [(A) Polymer]

[0097] The polymer (A) used in the organic film-forming composition of the present invention has a repeating unit represented by the above-mentioned general formula (1).

[0098] In the above general formula (1), R is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms. R may be a single species or a mixture of multiple species. Examples of R include the following.

[0099] [Chemistry 5]

[0100]

[0101] (where * represents the atomic bond with the oxygen atom)

[0102] Furthermore, the polymer (A) is preferably any one or more of the following general formulas (2) to (4).

[0103] [Chemistry 6]

[0104]

[0105] (In the formula, R1 is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms and may have an ether bond. R2 is a monovalent organic group having 1 to 30 carbon atoms, and n represents the average number of repeating units and is 3 to 2,000.)

[0106] In the above general formulae (2) to (4), R1 is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms and may have an ether bond. R1 may be a single species or a mixture of multiple species, and the following are examples. Among these, those having a glyme chain are preferred from the viewpoint of surface tension control.

[0107] [Chemistry 7]

[0108]

[0109] (where * represents the atomic bond with the oxygen atom)

[0110] In the above general formula (4), R2 is a monovalent organic group having 1 to 30 carbon atoms. Specifically, methyl, ethyl, vinyl, 2,2,2-trifluoroethyl, propyl, isopropyl, allyl, 1-propenyl, isopropenyl, butyl, sec-butyl, tert-butyl, isobutyl, pentyl, cyclopentyl, hexyl, cyclohexyl, cyclohexenyl, decyl, dodecyl, eicosyl, norbornyl, adamantyl, phenyl, toluoyl, xylyl, naphthyl, phenanthrenyl, anthracenyl, benzyl, fluorenyl, naphthylmethyl, norbornenyl, triacontyl, 2-furanyl, 2-tetrahydrofuranyl, anisyl, acryloyl, methacryloyl, and acetyl can be exemplified. When these R2 have an aromatic ring, they may have a substituent on the aromatic ring, and examples thereof include halogen groups such as fluorine, chlorine, bromine, and iodine, alkyloxy groups such as methoxy and ethoxy, alkenyloxy groups such as allyloxy, and alkynyloxy groups such as propargyloxy. The hydrogen atoms on the methylene groups constituting the alkylene groups may be substituted with fluorine atoms.

[0111] By including a polymer with such a structure, the surface tension of the organic film-forming composition is adjusted and the compatibility of the polymer in the solvent is also excellent, so an organic film with better in-plane uniformity can be formed by spin coating. In addition, by appropriately adjusting the structure and terminal structure of multiple R1, it is possible to adjust in a manner to achieve the desired performance.

[0112] n represents the average number of repeating units, and is 3 to 2,000, preferably 3 to 500, and more preferably 5 to 300.

[0113] The polymer (A) may have a single repeating unit represented by the general formula (1) or a combination of two or more repeating units.

[0114] Specific examples of the repeating unit represented by the general formula (1) include the following, but are not limited to these.

[0115] [Chemistry 8]

[0116]

[0117] Specific examples of the polymer (A) represented by the general formula (2) include the following, but are not limited to these.

[0118] [Chemistry 9]

[0119]

[0120] Specific examples of the polymer (A) represented by the general formula (3) include the following, but are not limited to these.

[0121] [Chemistry 10]

[0122]

[0123] Specific examples of the polymer (A) represented by the general formula (4) include the following, but are not limited to these.

[0124] [Chemistry 11]

[0125]

[0126] The properties of the polymer (A) can be adjusted as needed by selecting the structures of R, R1, and R2. In particular, the polarity of the polymer can be controlled to adjust the film-forming properties and solvent solubility.

[0127] The weight average molecular weight of the (A) polymer is preferably 300 to 200,000, more preferably 300 to 50,000, and even more preferably 500 to 40,000. The average number of repeating units is preferably 3 to 2,000, and more preferably 3 to 500. If the weight average molecular weight is 300 or more, the reduction in the blending effect due to volatilization, etc. can be suppressed, and a sufficient blending effect can be obtained. Moreover, if the weight average molecular weight is 200,000 or less, there is no deterioration in fluidity, etc., and the filling / planarization characteristics are excellent. The weight average molecular weight of the (A) polymer can be obtained, for example, as a polystyrene-converted weight average molecular weight (Mw) obtained by gel permeation chromatography (GPC) using tetrahydrofuran as the elution liquid (solvent).

[0128] As an example of a method for producing a polymer having a repeating unit represented by the general formula (1), there can be mentioned a method of obtaining the polymer by an etherification reaction of octafluorocyclopentene and a diol having R as a partial structure using a base catalyst as shown below.

[0129] [Chemistry 12]

[0130]

[0131] (In the formula, R is the same as above.)

[0132] As for the base catalyst of the etherification reaction represented above, inorganic base compounds such as sodium bicarbonate, sodium carbonate, potassium carbonate, calcium carbonate, cesium carbonate, sodium hydroxide, potassium hydroxide, sodium hydride, potassium phosphate, triethylamine, pyridine, organic amine compounds such as N-methylmorpholine, etc. can be listed, and they can be used alone or in combination of two or more. The amount of this catalyst used is 0.1 to 20 moles relative to the hydroxyl group of the substituent as the raw material, preferably in the range of 0.2 to 10 moles.

[0133] The solvent used at this time is not particularly limited as long as it is a solvent that is inactive for the above reaction. For example, ether solvents such as diethyl ether, tetrahydrofuran, and dioxane, aromatic solvents such as benzene, toluene, and xylene, acetonitrile, dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone, water, etc., can be used alone or in combination. These solvents can be used in a range of 0 to 2,000 parts by mass relative to 100 parts by mass of the reaction raw materials. The reaction temperature is preferably -50°C to about the boiling point of the solvent, and more preferably room temperature to 150°C. The reaction time is appropriately selected from 0.1 to 100 hours.

[0134] The obtained polymer may be purified, if necessary, by conventional methods such as liquid separation, crystallization, vacuum concentration, dialysis, ultrafiltration, etc., depending on its properties. In addition, the metal content may be reduced by passing the polymer through a commercially available metal removal filter, if necessary.

[0135] As for the reaction method, there are the following methods: a method of feeding octafluorocyclopentene and diols into a solvent in batches; a method of dripping octafluorocyclopentene and diols separately or mixing them and dispersing or dissolving them and then dripping them; a method of dispersing or dissolving any one of octafluorocyclopentene and diols in a solvent and then dripping the other one dispersed or dissolved in the solvent. In addition, if a variety of diols are fed, they can be mixed in advance and then reacted, or they can be reacted separately in sequence. If a catalyst is used, it can be listed as a method of feeding it with octafluorocyclopentene and diols in batches, a method of dripping the catalyst after pre-dispersing or dissolving it, etc. After the reaction is completed, in order to remove the unreacted raw materials, catalysts, etc. present in the system, it can also be diluted with an organic solvent, washed by liquid separation, and crystallized with a poor solvent to form a powder. In addition, it can also be diluted with an organic solvent, and the solvent can be replaced with a desired organic solvent and recovered in the form of a solution. After further being recovered as a powder by crystallization or the like, the powder can be dissolved in a desired organic solvent and recovered as a solution.

[0136] As for the organic solvent used for liquid separation and cleaning, there is no particular restriction as long as it can dissolve the target and separate into two layers even if mixed with water. For example, hydrocarbons such as hexane, heptane, benzene, toluene, and xylene, esters such as ethyl acetate, n-butyl acetate, and propylene glycol methyl ether acetate, ketones such as methyl ethyl ketone, methyl amyl ketone, cyclohexanone, and methyl isobutyl ketone, ethers such as diethyl ether, diisopropyl ether, methyl-tert-butyl ether, and ethyl cyclopentyl methyl ether, chlorine-based solvents such as methylene chloride, chloroform, ethylene dichloride, and trichloroethylene, and mixtures thereof, etc., can be listed. The cleaning water used at this time is usually deionized water or ultrapure water. The cleaning number can be more than 1 time, but even if cleaning is performed more than 10 times, the effect corresponding to the cleaning number may not be obtained, so it is preferably about 1 to 5 times.

[0137] In order to remove the acidic components in the system during separation and washing, an alkaline aqueous solution may be used for washing. Specific examples of the base include alkali metal hydroxides, alkali metal carbonates, alkaline earth metal hydroxides, alkaline earth metal carbonates, ammonia, and organic ammonium.

[0138] Furthermore, in order to remove metal impurities or alkaline components in the system during separation and cleaning, an acidic aqueous solution may be used for cleaning. Specifically, the acid includes inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, and heteropolyacids, and organic acids such as oxalic acid, fumaric acid, maleic acid, trifluoroacetic acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, and trifluoromethanesulfonic acid.

[0139] The liquid separation and washing using the alkaline aqueous solution and the acidic aqueous solution may be performed alone or in combination. Liquid separation and washing using the alkaline aqueous solution and the acidic aqueous solution in this order is more preferable from the viewpoint of removing metal impurities.

[0140] After the above-mentioned separation and washing using alkaline aqueous solution or acidic aqueous solution, it is also possible to wash with neutral water. The number of washings may be more than one, preferably about 1 to 5 times. As for neutral water, the above-mentioned deionized water, ultrapure water, etc. may be used. The number of washings may be more than one, but if the number of washings is small, the alkaline component and the acidic component may not be removed. Even if washing is performed more than 10 times, the effect corresponding to the number of washings may not be obtained, so it is preferably about 1 to 5 times.

[0141] Furthermore, the reaction product after the liquid separation operation can be concentrated and dried or crystallized in a solvent under reduced pressure or normal pressure to be recovered as a powder, but in order to improve the operability when preparing the organic film-forming composition, it can also be kept in a solution state of appropriate concentration. As for the concentration at this time, it is preferably 0.1 to 50% by mass, and more preferably 0.5 to 30% by mass. If it is such a concentration, the viscosity is not easy to increase, so the operability will not be damaged, and the amount of the solvent will not become too large, so it is economical.

[0142] The solvent at this time is not particularly limited as long as it can dissolve the reaction product. Specific examples include: ketones such as cyclohexanone and methyl-2-pentyl ketone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, and propylene glycol mono-tert-butyl ether acetate; these may be used alone or in combination of two or more.

[0143] The polymers represented by the above general formulas (2) and (3) can be easily produced by adjusting the ratio during the feeding of octafluorocyclopentene and the diol having R1 as a partial structure. Specifically, when the number of moles of octafluorocyclopentene during feeding is a, and the number of moles of the diol having R1 as a partial structure during feeding is b, in the case of (2), it is sufficient to make the feeding ratio of the diol having R1 as a partial structure relative to octafluorocyclopentene higher, that is, to make the feeding ratio a < b. In this case, since the diol component is in excess, unreacted alcohol can remain at the terminal. Similarly, in the case of (3), it is sufficient to make the feeding ratio of octafluorocyclopentene relative to the diol having R1 as a partial structure higher, that is, to make the feeding ratio a > b. In this case, it will be in a form where the terminal is capped with octafluorocyclopentene.

[0144] [Manufacturing method of (2): When the feeding ratio is a < b]

[0145] [Chemical formula 13]

[0146]

[0147] (In the formula, R1 and n are as described above.)

[0148] [Manufacturing method of (3): When the feeding ratio is a > b]

[0149] [Chemical formula 14]

[0150]

[0151] (In the formula, R1 and n are as described above.)

[0152] In addition, in the case of the above general formula (4), there are a method of using the polymer represented by the above general formula (3) and further etherifying the terminal with an alcohol or carboxylic acid having R2 as a substituent, or a method of batchwise etherifying the diol having R1 as a partial structure and the alcohol or carboxylic acid having R2 as a substituent with octafluorocyclopentene. When batchwise charging, the feeding ratio must be strictly controlled. Industrially, it is better to produce the polymer represented by (3) and then cap the terminal with an alcohol or carboxylic acid having R2 as a substituent.

[0153] [Terminal capping of the polymer of (3)]

[0154] [Chemical formula 15]

[0155]

[0156] (In the formula, R1, R2, and n are as described above.)

[0157] [Batch charging]

[0158] [Chemical formula 16]

[0159]

[0160] (In the formula, R1, R2, and n are the same as described above.)

[0161] The production methods (2) and (3) can be carried out by adjusting the feed ratio of octafluorocyclopentene and the diol having R1 as a partial structure so that the feed ratio is matched with the desired structure, and the method described in the production method of the above-mentioned (1) can be used. The reaction method and the recovery method of the polymer can be carried out by the method described in the production method of the polymer of the general formula (1) described above.

[0162] Furthermore, when the production method (4) is carried out by batch input, the diol having R1 as a partial structure and the alcohol or carboxylic acid having R2 as a substituent are used simultaneously, and the production method, reaction method and polymer recovery method of (1) can be followed. When the end capping of the polymer (3) is carried out, there is a method of first recovering the polymer (3) and then reacting it with the alcohol or carboxylic acid having R2 as a substituent in the same manner as the polymer production method (1), and a method of reacting the diol having R1 as a partial structure in the reaction of producing the polymer (3) and then adding the alcohol or carboxylic acid having R2 as a substituent for end capping to react in one pot. In any of the above reaction methods, only the substrate is changed, and the production method, reaction method and polymer recovery method of (1) can be followed.

[0163] [(B) Organic film-forming resin]

[0164] The (B) organic film-forming resin used in the organic film-forming composition of the present invention is not particularly limited as long as it is a resin or compound that satisfies the film-forming and curing properties required for spin coating. However, from the perspectives of etching resistance, optical properties, heat resistance, etc., a resin or compound containing an aromatic skeleton is more ideal.

[0165] Examples of the aromatic skeleton include benzene, naphthalene, anthracene, pyrene, indene, fluorene, furan, pyrrole, thiophene, oxazole, pyrazole, oxazole, isoxazole, thiazole, pyridine, pyrazine, pyrimidine, pyridazine, triazine, and carbazole. Among these, benzene, naphthalene, fluorene, and carbazole are particularly preferred.

[0166] As (B) the organic film-forming resin used in the present invention, resins having the following structures and the like described in JP-A-2012-001687 and JP-A-2012-077295 can be exemplified.

[0167] [Chemistry 17]

[0168]

[0169] (In formula (1), the ring structures Ar1 and Ar2 represent a benzene ring or a naphthalene ring. X represents a single bond or an alkylene group having 1 to 20 carbon atoms. m represents 0 or 1. n represents any natural number that makes the molecular weight 100,000 or less. In addition, the symbols in the formula are applicable only to this formula.)

[0170] [Chemistry 18]

[0171]

[0172] (In formula (2), the ring structures Ar1 and Ar2 represent a benzene ring or a naphthalene ring. n represents an arbitrary natural number that makes the polystyrene-equivalent weight average molecular weight obtained by gel permeation chromatography 100,000 or less. In addition, the symbols in the formula are applicable only to this formula.)

[0173] Examples of the organic film-forming resin (B) used in the present invention include resins having the following structures and described in Japanese Patent Application Laid-Open Nos. 2004-264710, 2005-043471, 2005-250434, 2007-293294, and 2008-065303.

[0174] [Chemistry 19]

[0175]

[0176] (In formula (3) and formula (4), R 1 and R 2 represents a hydrogen atom or an alkyl or aryl group having 1 to 3 carbon atoms, and R 3 represents an alkyl group, vinyl group, allyl group, or aryl group which may be substituted and has 1 to 3 carbon atoms, n represents 0 or 1, and m represents 0, 1, or 2. In addition, the symbols in the formula are applicable only to this formula.)

[0177] [Chemistry 20]

[0178]

[0179] (In formula (5), R1 is a monovalent atom or group other than a hydrogen atom, and n is an integer of 0 to 4. However, when n is 2 to 4, multiple R1s may be the same or different. R2 and R3 are independently monovalent atoms or groups. X is a divalent group. In addition, the symbols in the formula are applicable only to this formula.)

[0180] [Chemistry 21]

[0181]

[0182] (In formula (6), R1 is a hydrogen atom or a methyl group. R2 is any one of a single bond, a linear, branched, or cyclic alkylene group having 1 to 20 carbon atoms, and an arylene group having 6 to 10 carbon atoms, and may also be any one of an ether, an ester, a lactone, and an amide. 3 , R 4 Each is a hydrogen atom or a glycidyl group. X represents a polymer of any one of an indene skeleton-containing hydrocarbon, a cycloolefin having 3 to 10 carbon atoms, and maleimide, and may have any one of an ether, an ester, a lactone, and a carboxylic anhydride. 5 , R 6 Each is any one of a hydrogen atom, a fluorine atom, a methyl group, and a trifluoromethyl group. 7 It is any one of a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, a hydroxyl group, or an alkoxycarbonyl group. p and q are each an integer of 1 to 4. r is an integer of 0 to 4. a, b, and c are each in the range of 0.5≤a+b+c≤1, 0≤a≤0.8, 0≤b≤0.8, 0.1≤a+b≤0.8, and 0.1≤c≤0.8. In addition, the symbols in the formula apply only to this formula. )

[0183] [Chemistry 22]

[0184]

[0185] (In formula (7), R1 represents a hydrogen atom or a monovalent organic group, and R2 and R3 independently represent a monovalent atom or a monovalent organic group. In addition, the symbols in the formula are applicable only to this formula.)

[0186] Specific examples of the (B) organic film-forming resin used in the present invention include resins having the following structures and described in Japanese Patent Application Laid-Open Nos. 2004-205685, 2007-171895, and 2009-014816.

[0187] [Chemistry 23]

[0188]

[0189] (In formula (8) and formula (9), R 1 ~R 8 Each of them is independently a hydrogen atom, a hydroxyl group, a substituted alkyl group having 1 to 6 carbon atoms, a substituted alkoxy group having 1 to 6 carbon atoms, a substituted alkoxycarboxyl group having 2 to 6 carbon atoms, a substituted aryl group having 6 to 10 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, an isocyanate group or an epoxypropyl group. m and n are positive integers. In addition, the symbols in the formula are applicable only to this formula.)

[0190] [Chemistry 24]

[0191]

[0192] (In formula (10), R 1 , R 6 is a hydrogen atom or a methyl group. R 2 , R 3 , R 4 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group, a hydroxyl group, an acetoxy group, an alkoxycarbonyl group, or an aryl group having 6 to 10 carbon atoms, R 5 is a condensed polycyclic hydrocarbon group having 13 to 30 carbon atoms, -O-R 7 , -C(=O)-O-R 7 , -O-C(=O)-R 7 or -C(=O)-NR 8 -R 7 , m is 1 or 2, n is an integer from 0 to 4, and p is an integer from 0 to 6. R 7 is an organic group having 7 to 30 carbon atoms, R 8 is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. Z is any one of a methylene group, -O-, -S-, -NH-. a, b, c, d, e are each in the range of 0 < a < 1.0, 0 ≤ b ≤ 0.8, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, 0 < b + c + d + e < 1.0. In addition, the notations in the formula are only applicable in this formula.)

[0193] [Chemical formula 25]

[0194]

[0195] (In formula (11), n represents 0 or 1. R 1 represents a methylene group which may be substituted, an alkylene group having 2 to 20 carbon atoms which may be substituted, or an arylene group having 6 to 20 carbon atoms which may be substituted. R 2 represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may be substituted, or an aryl group having 6 to 20 carbon atoms which may be substituted. R 3 to R 7 represent a hydroxyl group, an alkyl group having 1 to 6 carbon atoms which may be substituted, an alkoxy group having 1 to 6 carbon atoms which may be substituted, an alkoxycarbonyl group having 2 to 10 carbon atoms which may be substituted, an aryl group having 6 to 14 carbon atoms which may be substituted, or a glycidyl ether group having 2 to 6 carbon atoms which may be substituted. R 9 represents a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, a linear, branched or cyclic alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. In addition, the notations in the formula are only applicable in this formula.)

[0196] As formula (11), for example, the following resins can be exemplified.

[0197] [Chemical formula 26]

[0198]

[0199] [Chemistry 27]

[0200]

[0201] Examples of the (B) organic film-forming resin used in the present invention include resins having the following structures and described in Japanese Patent Application Laid-Open Nos. 2007-199653, 2008-274250, and 2010-122656.

[0202] [Chemistry 28]

[0203]

[0204] (In formula (12), R 1 With R 2 are independently the same or different hydrogen atoms, linear, branched or cyclic alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 10 carbon atoms or alkenyl groups having 2 to 10 carbon atoms, R 3 is a single bond or an alkylene group having a linear, branched or cyclic structure and having 1 to 30 carbon atoms, and may also have a bridged cyclic hydrocarbon group, a double bond, a heteroatom or an aromatic group having 6 to 30 carbon atoms, R 4 With R 5 Each is independently a hydrogen atom or an epoxypropyl group, and n is an integer of 1 to 4. In addition, the symbols in the formula are applicable only to this formula.

[0205] [Chemistry 29]

[0206]

[0207] (In formula (13), R 1 With R 2 are independently the same or different hydrogen atoms, linear, branched or cyclic alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 10 carbon atoms or alkenyl groups having 2 to 10 carbon atoms, R 3 is a single bond or an alkylene group having a linear, branched or cyclic structure and having 1 to 30 carbon atoms, and may also have a bridged cyclic hydrocarbon group, a double bond, a heteroatom or an aromatic group having 6 to 30 carbon atoms, R 4 With R 5 are each independently a hydrogen atom or a glycidyl group, R 6 is a single bond or a linear or branched alkylene group having 1 to 10 carbon atoms. In addition, the symbols in the formula apply only to this formula.

[0208] [Chemistry 30]

[0209]

[0210] (In formula (14), ring Z 1 and ring Z 2 represent a condensed polycyclic aromatic hydrocarbon ring, R 1a , R 1b , R 2a and R 2b are the same or different and represent substituents. k1 and k2 are the same or different and represent an integer of 0 or 1 to 4, m1 and m2 each represent an integer of 0 or 1 or more, and n1 and n2 each represent an integer of 0 or 1 or more. However, n1 + n2 ≥ 1. In addition, the notations in the formula are only applicable in this formula.)

[0211] [Chemical formula 31]

[0212]

[0213] (In formula (15), R1 and R2 are the same or different hydrogen atoms, linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms, aryl groups having 6 to 10 carbon atoms, or alkenyl groups having 2 to 10 carbon atoms. R 3 , R 4 are each a hydrogen atom or a glycidyl group, R 5 is a single bond, a linear or branched alkylene group having 1 to 10 carbon atoms, R 6 , R 7 are a benzene ring or a naphthalene ring. p and q are each 1 or 2. n satisfies 0 < n ≤ 1. In addition, the notations in the formula are only applicable in this formula.)

[0214] As formula (15), for example, the following resins can be exemplified.

[0215] [Chemical formula 32]

[0216]

[0217] [Chemical formula 33]

[0218]

[0219] [Chemical formula 34]

[0220]

[0221] [Chemical formula 35]

[0222]

[0223] As the resin for forming the (B) organic film used in the present invention, resins having the following structures described in Japanese Patent Laid-Open No. 2012-214720 and the like can be exemplified.

[0224] [Chemical formula 36]

[0225]

[0226] (In formula (16), the ring structures Ar1 and Ar2 represent a benzene ring or a naphthalene ring. x and z each independently represent 0 or 1. In addition, the symbols in the formula are applicable only to this formula.)

[0227] Examples of the (B) organic film-forming resin used in the present invention include resins described in Japanese Patent Application Laid-Open No. 2014-29435.

[0228] [Chemistry 37]

[0229]

[0230] (In formula (17), A represents a structure having carbazole, B represents a structure having an aromatic ring, C represents a hydrogen atom, an alkyl group or a structure having an aromatic ring, and B and C may form a ring with each other. The combined structure of A, B and C contains 1 to 4 carboxyl groups or their salts, or carboxylate groups. In addition, the symbols in the formula are applicable only to this formula.)

[0231] In addition, as the (B) organic film-forming resin used in the present invention, there can be exemplified a polymer described in International Publication No. 2012 / 077640, which contains a unit structure represented by the following formula (18) and a unit structure represented by the following formula (19), wherein the ratio of the unit structure represented by formula (18) to the unit structure represented by formula (19) is 3 to 97:97 to 3 in molar ratio.

[0232] [Chemistry 38]

[0233]

[0234] (In formula (18), R1 and R2 each independently represent a hydrogen atom, a halogen atom, a nitro group, an amino group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a combination of these groups which may also contain an ether bond, a ketone bond, or an ester bond. R3 represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a combination of these groups which may also contain an ether bond, a ketone bond, or an ester bond. Combinations of these groups. R4 represents a hydrogen atom, or an aryl or heterocyclic group with 6 to 40 carbon atoms which may be substituted by a halogen atom, a nitro group, an amino group or a hydroxyl group; R5 represents a hydrogen atom, or an alkyl group with 1 to 10 carbon atoms, or an aryl or heterocyclic group with 6 to 40 carbon atoms which may be substituted by a halogen atom, a nitro group, an amino group or a hydroxyl group; R4 and R5 may also form a ring with each other. n1 and n2 each represent an integer of 1 to 3. In addition, the symbols in the formula apply only to this formula.)

[0235] [Chemistry 39]

[0236]

[0237] (In formula (19), Ar represents an aromatic ring group having 6 to 20 carbon atoms, R6 represents a hydroxyl group, R7 represents a hydrogen atom, a halogen atom, a nitro group, an amino group, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, or a combination of these groups which may contain an ether bond, a keto bond, or an ester bond. R8 represents a hydrogen atom, or an aryl group or a heterocyclic group having 6 to 40 carbon atoms which may be substituted by a halogen atom, a nitro group, an amino group, or a hydroxyl group, R9 represents a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms, an aryl group or a heterocyclic group having 6 to 40 carbon atoms which may be substituted by a halogen atom, a nitro group, an amino group, or a hydroxyl group, and R8 and R9 may form a ring with each other. n6 represents an integer from 1 to p, and n7 represents an integer from p to n6. Here, p represents the maximum number that can be substituted in the aromatic ring group Ar. In addition, the symbols in the formula are applicable only to this formula.)

[0238] As the (B) organic film-forming resin used in the present invention, there can be exemplified a polymer having a unit structure represented by the following formula (20) described in International Publication No. 2010 / 147155.

[0239] [Chemistry 40]

[0240]

[0241] (In formula (20), R1 and R2 are each selected from the group consisting of a hydrogen atom, a halogen group, a nitro group, an amino group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, and a combination thereof, and the alkyl group, the alkenyl group, or the aryl group may also contain an ether bond, a ketone bond, or an ester bond, and R3 is selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 40 carbon atoms, and a combination thereof, and the alkyl group , the alkenyl or aryl group may also contain an ether bond, a ketone bond or an ester bond, R4 represents an aryl or heterocyclic group having 6 to 40 carbon atoms which may be substituted by a halogen group, a nitro group, an amino group or a hydroxyl group, R5 represents a hydrogen atom, or an alkyl group having 1 to 10 carbon atoms, an aryl or heterocyclic group having 6 to 40 carbon atoms which may be substituted by a halogen group, a nitro group, an amino group or a hydroxyl group, and R4 and R5 may also form a ring together with the carbon atoms to which they are bonded, and n1 and n2 are each an integer of 1 to 3. In addition, the symbols in the formula are applicable only to this formula. )

[0242] As the (B) organic film-forming resin used in the present invention, examples include novolac resins obtained by reacting one or more phenols such as phenol, cresol, xylenol, catechol, resorcinol, hydroquinone, gallol, hydroxyhydroquinone, and phloroglucinol with one or more aldehyde sources such as formaldehyde, trioxymethylene, and trioxane using an acidic catalyst, and resins containing a repeating unit structure represented by the following formula (21) as recorded in International Publication No. 2012 / 176767.

[0243] [Chemistry 41]

[0244]

[0245] (In formula (21), A represents a hydroxy-substituted phenylene group derived from polyhydroxybenzene, and B represents a monovalent condensed aromatic hydrocarbon ring group formed by condensing 2 to 6 benzene rings. The symbols in the formula are applicable only to this formula.)

[0246] As for the (B) organic film-forming resin used in the present invention, the novolac resin having a fluorene or tetrahydrospirobiindene structure described in JP-A-2005-128509, JP-A-2006-259249, JP-A-2006-259482, JP-A-2006-293298, and JP-A-2007-316282 can be exemplified by resins containing a repeating unit structure represented by the following formula (22-1) or (22-2).

[0247] [Chemistry 42]

[0248]

[0249] (In formula (22-1) and formula (22-2), R 1 , R 2 , R 6 , R 7 are independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an allyl group or a halogen atom, R 3 , R 4 , R 8 , R 9 are independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, a linear, branched or cyclic alkenyl group having 2 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms or a glycidyl group, and R 5 , R 14 R is independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. n, m, p and q are integers of 1 to 3. 10 ~R 13are independently a hydrogen atom, a halogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, or a linear, branched or cyclic alkoxy group having 1 to 6 carbon atoms. In addition, the symbols in the formula apply only to this formula.)

[0250] As the (B) organic film-forming resin used in the present invention, a reaction product obtained by the method described in Japanese Patent Application Publication No. 2012-145897 can be exemplified. More specifically, a polymer obtained by condensing one or more compounds represented by the following general formula (23-1) and / or (23-2) with one or more compounds represented by the following general formula (24-1) and / or (24-2) and / or their equivalents can be exemplified.

[0251] [Chemistry 43]

[0252]

[0253] (In general formula (23-1) and general formula (23-2), R 1 ~R 8 Each of them is independently a hydrogen atom, a halogen atom, a hydroxyl group, an isocyano group, a glycidyloxy group, a carboxyl group, an amino group, an alkoxy group having 1 to 30 carbon atoms, an alkoxycarbonyl group having 1 to 30 carbon atoms, an alkanoyloxy group having 1 to 30 carbon atoms, or an optionally substituted saturated or unsaturated organic group having 1 to 30 carbon atoms. 1 ~R 4 or R 5 ~R 8 Two substituents selected arbitrarily from among them are bonded to further form a cyclic substituent. In addition, the symbols in the formula are applicable only to this formula. )

[0254] [Chemistry 44]

[0255]

[0256] (In general formula (24-1) and general formula (24-2), Q is an organic group having 1 to 30 carbon atoms which may be substituted, and two Qs selected arbitrarily in the molecule may be bonded to form a cyclic substituent. n1 to n6 are the numbers of the substituents, n1 to n6 = 0, 1, 2, and formula (24-1) excludes hydroxybenzaldehyde. In formula (24-2), the relationship of 0≤n3+n5≤3, 0≤n4+n6≤4, and 1≤n3+n4≤4 is satisfied. In addition, the symbols in the formula are applicable only to this formula.)

[0257] In addition, examples include polymers obtained by condensing one or more compounds represented by the above-mentioned general formula (23-1) and / or (23-2), one or more compounds represented by the above-mentioned general formula (24-1) and / or (24-2) and / or their equivalents, and one or more compounds represented by the following general formula (25) and / or their equivalents.

[0258] [Chemistry 45]

[0259] Y-CHO (25)

[0260] (In formula (25), Y is a hydrogen atom or a monovalent organic group having 30 or less carbon atoms which may have a substituent. Formula (25) is different from general formula (24-1) and general formula (24-2). In addition, the symbols in the formula are applicable only to this formula.)

[0261] As the (B) organic film-forming resin used in the present invention, compounds having the following structure described in JP-A-2017-119671 and the like can be exemplified.

[0262] [Chemistry 46]

[0263]

[0264] (In formula (26-1), R is a single bond or an organic group having 1 to 50 carbon atoms, X is a group represented by the following general formula (26-2), and m1 is an integer satisfying 2≤m1≤10. In addition, the symbols in the formula are applicable only to this formula.)

[0265] [Chemistry 47]

[0266]

[0267] (Where X 2 is a divalent organic group having 1 to 10 carbon atoms, n1 is 0 or 1, n2 is 1 or 2, X 3 is a group represented by the following general formula (26-3), and n5 is 0, 1 or 2. In addition, the symbols in the formula are applicable only to this formula.

[0268] [Chemistry 48]

[0269]

[0270] (Where R 10 It is a hydrogen atom or a saturated or unsaturated hydrocarbon group with 1 to 10 carbon atoms. The hydrogen atoms on the benzene ring in the formula may also be replaced by a methyl group or a methoxy group. In addition, the symbols in the formula are only applicable to this formula.)

[0271] Examples of the compound having the above structure include the following compounds.

[0272] [Chemistry 49]

[0273]

[0274] As the (B) organic film-forming resin used in the present invention, there can be exemplified a polymer having a repeating unit represented by the following general formula (27-1) described in JP-A-2019-044022.

[0275] [Chemistry 50]

[0276]

[0277] (In formula (27-1), AR1 and AR2 are benzene rings or naphthalene rings which may have substituents, and R 1 , R 2 Each independently represents a hydrogen atom or an organic group having 1 to 30 carbon atoms, R 1 and R 2 When it is an organic group, R 1 With R 2 They can also be bonded within the molecule to form a cyclic organic group. n is 0 or 1. When n=0, AR1 and AR2 do not form a bridge structure between the aromatic rings of AR1 and AR2 via Z. When n=1, AR1 and AR2 form a bridge structure between the aromatic rings of AR1 and AR2 via Z. Z is a single bond or any one of the following formulas (27-2). Y is a group represented by the following formula (27-3). In addition, the symbols in the formula are only applicable to this formula. )

[0278] [Chemistry 51]

[0279]

[0280] [Chemistry 52]

[0281] ----R 3 -C≡CR 4 (27-3)

[0282] (Where R 3 is a single bond or a divalent organic group having 1 to 20 carbon atoms, R 4 It is a hydrogen atom or a monovalent organic group with 1 to 20 carbon atoms. The dotted line represents an atomic bond. In addition, the symbols in the formula are applicable only to this formula.)

[0283] Examples of the polymer having a repeating unit represented by the general formula (27-1) include the following polymers.

[0284] [Chemistry 53]

[0285]

[0286] [Chemistry 54]

[0287]

[0288] (B) The organic film-forming resin may be synthesized by a known method, or a commercially available product may be used.

[0289] The amount of the aforementioned (B) organic film-forming resin blended is not particularly limited as long as it satisfies the film-forming properties of the organic film-forming composition by spin coating. When the aforementioned organic film-forming composition is 100 parts by mass, the content of the aforementioned (B) organic film-forming resin is preferably 10 to 40 parts by mass, more preferably 10 to 30 parts by mass, and even more preferably 10 to 25 parts by mass. For example, when the organic film-forming composition is used to fill holes and trenches with very high aspect ratios of the 3D NAND memory architecture, it is necessary to increase the blending amount of the organic film-forming resin. However, on the other hand, the viscosity of the organic film-forming composition after increasing the blending amount of the resin is high, and the in-plane uniformity and filling characteristics after spin coating are deteriorated. Even with the blending ratio of the aforementioned (B) organic film-forming resin, the organic film-forming composition of the present invention can still form an organic film with excellent in-plane uniformity and filling characteristics, so it can be used ideally.

[0290] The content of the polymer (A) is preferably 0.01 to 5 parts by mass relative to 100 parts by mass of the organic film-forming resin (B). The organic film-forming composition containing such a polymer content can provide a more excellent in-plane uniformity of the formed organic film.

[0291] [(C) Solvent]

[0292] The (C) solvent that can be used in the organic film-forming composition of the present invention is not particularly limited as long as it can dissolve the aforementioned (B) organic film-forming resin and the aforementioned (A) polymer, and is preferably a solvent that can also dissolve the acid generator, crosslinking agent, surfactant, etc. described below. Specifically, ketones such as 2-heptanone, cyclopentanone, and cyclohexanone; alcohols such as 3-methoxybutanol, 3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and 1-ethoxy-2-propanol; ethers such as propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, and diethylene glycol dimethyl ether; esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, γ-butyrolactone, and propylene glycol mono-tert-butyl ether acetate; one or more of them may be used in combination, but are not limited to these.

[0293] Among them, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, 2-heptanone, cyclopentanone, cyclohexanone, γ-butyrolactone, and a mixture of two or more thereof are preferably used.

[0294] The content of the solvent (C) is 200 to 10,000 parts by mass, more preferably 300 to 5,000 parts by mass, based on 100 parts by mass of the organic film-forming resin (B). The concentration can be adjusted within such a range in accordance with the desired film thickness.

[0295] [Other ingredients]

[0296] In addition, an acid generator and a crosslinking agent may be added to the organic film forming composition of the present invention to further promote the crosslinking reaction. As for the acid generator, there are those that generate acid due to thermal decomposition and those that generate acid due to light exposure, and both can be added. As the acid generator, specifically, those described in paragraphs

[0061] to

[0085] of Japanese Patent Gazette No. 2007-199653 can be cited. The above-mentioned acid generator can be used alone or in combination of two or more. The amount of the acid generator added is preferably 0.05 to 50 parts by mass, and more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the organic film forming resin (B). If it is such an amount, the crosslinking reaction can be promoted and a dense film can be formed.

[0297] Furthermore, as a crosslinking agent, specifically, those described in paragraphs

[0055] to

[0060] of Japanese Patent Publication No. 2007-199653 can be cited. The above crosslinking agents can be used alone or in combination of two or more. The amount of the crosslinking agent added is preferably 1 to 100 parts by mass, more preferably 5 to 50 parts by mass, relative to 100 parts by mass of the organic film-forming resin (B). If it is such an amount, the curability can be improved and intermixing with the upper film can be further suppressed.

[0298] In addition, a surfactant may be added to the organic film forming composition of the present invention to further improve the in-plane uniformity during spin coating. As the surfactant, specifically, those recorded in paragraphs

[0142] to

[0147] of Japanese Patent Publication No. 2009-269953 may be cited. The above-mentioned surfactant may be used alone or in combination of two or more. The amount added when the surfactant is added is preferably 0.01 to 10 parts by mass, and more preferably 0.05 to 5 parts by mass, relative to 100 parts by mass of the organic film forming composition. If it is such an amount, an organic film with excellent in-plane uniformity can be formed.

[0299] In addition, a basic compound for improving storage stability can be added to the organic film forming composition of the present invention. The basic compound will play the role of a quencher for the acid to prevent the trace acid generated by the acid generator from causing the cross-linking reaction to proceed. As such a basic compound, specifically, those recorded in paragraphs

[0086] to

[0090] of Japanese Patent Publication No. 2007-199653 can be cited. The above-mentioned basic compounds can be used alone or in combination of two or more. The amount of the basic compound added is preferably 0.05 to 50 parts by mass, and more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the organic film forming resin (B). If it is such an amount, the storage stability of the organic film forming composition can be improved.

[0300] As described above, the organic film forming composition of the present invention is an organic film forming composition that is excellent in suppressing bulging during the EBR step. Therefore, the organic film forming composition of the present invention is extremely useful as a resist underlayer film material (organic film material) for multilayer resist processing such as a two-layer resist processing, a three-layer resist processing using a silicon-containing resist interlayer or a silicon-containing inorganic hard mask interlayer, and a four-layer resist processing using a silicon-containing resist interlayer or a silicon-containing inorganic hard mask interlayer and an organic antireflection film or a bonding film.

[0301] [Organic film formation method]

[0302] The present invention provides an organic film forming method, which is an organic film forming method used in the manufacturing steps of a semiconductor device, and is characterized in that: the organic film forming composition of the present invention is spin-coated on a processed substrate, and the substrate coated with the organic film forming composition is heat-treated at a temperature of more than 100°C and less than 600°C and in a range of 10 to 600 seconds to harden it, thereby forming an organic film.

[0303] In this method for forming an organic film, the organic film forming composition of the present invention is first spin-coated (spin-coated) on the substrate to be processed. By using the spin coating method, good filling characteristics can be obtained. After removing the film at the end in the EBR step, baking (heat treatment) is performed to promote the cross-linking reaction. In addition, by this baking, the solvent in the composition can be evaporated, so when the resist upper film and the silicon-containing resist intermediate film are formed on the organic film, mixing can also be prevented.

[0304] The baking is performed at a temperature of 100°C to 600°C for 10 to 600 seconds, preferably at a temperature of 200°C to 500°C for 10 to 300 seconds. Considering the effects of device damage and wafer deformation, the upper limit of the heating temperature in the photolithography wafer processing is preferably 600°C or less, more preferably 500°C or less. By performing heat treatment under such conditions, the cross-linking reaction can be promoted and an organic film that does not mix with the film formed on the upper layer can be formed.

[0305] [Pattern Formation Method]

[0306] Hereinafter, a pattern forming method using the organic film-forming composition of the present invention will be described.

[0307] [Three-layer resist processing using a silicon-containing resist interlayer]

[0308] The present invention provides a pattern forming method, characterized in that:

[0309] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0310] A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material.

[0311] A resist upper layer film is formed on the silicon-containing resist intermediate film using a resist upper layer film material composed of a photoresist composition.

[0312] Forming a circuit pattern on the resist upper film,

[0313] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the silicon-containing resist intermediate film by etching.

[0314] The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0315] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0316] As for the processed body, it is preferable to use a semiconductor device substrate or a substrate obtained by forming any one of a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxide carbide film and a metal oxide nitride film on the aforementioned semiconductor device substrate. More specifically, without particular limitation, Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al and other substrates, and a substrate obtained by forming the above-mentioned metal films on the aforementioned substrate as a processed layer can be used.

[0317] As for the processed layer, various Low-k films and barrier films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si, etc. can be used, and the thickness can usually be formed to 50 to 10,000nm, especially 100 to 5,000nm. In addition, when forming the processed layer, different materials can be used for the substrate and the processed layer.

[0318] In addition, as a metal constituting the workpiece, silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum or an alloy thereof is preferably used.

[0319] When an organic film is formed on a workpiece using the organic film-forming composition of the present invention, the organic film-forming method of the present invention described above may be used.

[0320] Next, a resist interlayer film material containing silicon atoms is used to form a resist interlayer film (silicon-containing resist interlayer film) on the organic film. As a resist interlayer film material containing silicon atoms, a polysiloxane-based interlayer film material is preferably used. By making the silicon-containing resist interlayer film have an anti-reflection effect, reflection can be suppressed. Especially for 193nm exposure, if a material containing many aromatic groups and having a high etching selectivity with the substrate is used as a composition for forming an organic film, the k value will become higher and the substrate reflection will increase, but by making the silicon-containing resist interlayer film have an absorption that can reach an appropriate k value, reflection can be suppressed and the substrate reflection can be made less than 0.5%. As a silicon-containing resist intermediate film with anti-reflective effect, if it is used for 248nm and 157nm exposure, it is preferable to use a polysiloxane that contains anthracene in the pendant structure and can be cross-linked by acid or heat. If it is used for 193nm exposure, it is preferable to use a polysiloxane that contains phenyl or a light-absorbing group with a silicon-silicon bond in the pendant structure and can be cross-linked by acid or heat.

[0321] Next, a resist upper film is formed on the silicon-containing resist intermediate film using a resist upper film material composed of a photoresist composition. As for the resist upper film material, both positive and negative types are acceptable, and the same photoresist composition as commonly used can be used. After the resist upper film material is spin-coated, it is ideal to pre-bake it at 60 to 180°C for 10 to 300 seconds. Thereafter, exposure is performed according to the usual method, and post-exposure baking (PEB) and development are further performed to obtain a resist upper film pattern. In addition, the thickness of the resist upper film is not particularly limited, and is preferably 30 to 500 nm, and particularly preferably 50 to 400 nm.

[0322] Next, a circuit pattern (resist upper film pattern) is formed on the resist upper film. When forming the circuit pattern, it is preferable to form the circuit pattern by photolithography using light with a wavelength of 10 nm to 300 nm, direct drawing using an electron beam, nanoimprinting, or a combination thereof.

[0323] In addition, as exposure light, high-energy rays with a wavelength of less than 300nm can be listed, specifically, far ultraviolet rays, KrF excimer laser (248nm), ArF excimer laser (193nm), F2 laser (157nm), Kr2 laser (146nm), Ar2 laser (126nm), 3 to 20nm soft X-rays (EUV), electron beams (EB), ion beams, X-rays, etc.

[0324] Furthermore, when forming the circuit pattern, it is preferable to develop the circuit pattern using an alkali developer or an organic solvent.

[0325] Next, the resist upper film with the circuit pattern formed thereon is used as a mask and the pattern is transferred to the silicon-containing resist intermediate film by etching. The etching of the silicon-containing resist intermediate film using the resist upper film pattern as a mask is preferably performed using a fluorocarbon gas. Thus, the silicon-containing resist intermediate film pattern is transferred.

[0326] Next, the silicon-containing resist intermediate film with the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching. The silicon-containing resist intermediate film shows resistance to etching by oxygen or hydrogen, so the etching of the organic film using the silicon-containing resist intermediate film pattern as a mask is preferably performed using an etching gas mainly composed of oxygen or hydrogen. In this way, the organic film pattern is transferred.

[0327] Next, the organic film with the transferred pattern is used as a mask and the pattern is transferred to the workpiece by etching. The subsequent etching of the workpiece (the workpiece layer) can be carried out according to the usual method. For example, if the workpiece is a SiO2, SiN, or silicon dioxide-based low dielectric constant insulating film, etching is performed mainly using a fluorine-based gas. If it is p-Si, Al, or W, etching is performed mainly using a chlorine-based or bromine-based gas. When the substrate is processed by etching using a fluorine-based gas, the pattern of the silicon-containing resist lower film will be stripped off while the substrate is being processed. On the other hand, when the substrate is processed by etching using a chlorine-based or bromine-based gas, it is necessary to perform dry etching stripping using a fluorine-based gas after the substrate is processed to strip off the pattern of the silicon-containing resist lower film.

[0328] The organic film obtained by using the organic film-forming composition of the present invention can have excellent etching resistance when etching the above-mentioned object to be processed.

[0329] [Four-layer resist process using silicon-containing resist interlayer and organic antireflection film or adhesion film]

[0330] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0331] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0332] A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material.

[0333] forming an organic antireflection film or a close-fitting film on the aforementioned silicon-containing resist intermediate film,

[0334] On the organic antireflection film or the adhesion film, a resist upper layer film is formed using a resist upper layer film material composed of a photoresist composition,

[0335] forming a circuit pattern on the resist upper film,

[0336] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the silicon-containing resist intermediate film by etching.

[0337] The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0338] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0339] This method can be performed in the same manner as the above-mentioned three-layer resist process using the silicon-containing resist interlayer film, except that an organic antireflection film (BARC) or an adhesion film is formed between the silicon-containing resist interlayer film and the resist upper layer film.

[0340] The organic anti-reflection film and the adhesion film can be formed by spin coating using a known organic anti-reflection film material.

[0341] [Three-layer resist processing using an inorganic hard mask interlayer]

[0342] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0343] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0344] forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the aforementioned organic film,

[0345] A resist upper layer film is formed on the inorganic hard mask intermediate film using a resist upper layer film material composed of a photoresist composition.

[0346] Forming a circuit pattern on the resist upper film,

[0347] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the inorganic hard mask intermediate film by etching.

[0348] The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0349] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0350] This method can be performed in the same manner as the above-mentioned three-layer resist process using the silicon-containing resist interlayer film, except that an inorganic hard mask interlayer film is formed on the organic film instead of the silicon-containing resist interlayer film.

[0351] The inorganic hard mask interlayer film selected from silicon oxide film, silicon nitride film and silicon oxide nitride film (SiON film) can be formed by CVD method, ALD method and the like. The method for forming the silicon nitride film is described in, for example, Japanese Patent Application Publication No. 2002-334869 and International Publication No. 2004 / 066377. The film thickness of the inorganic hard mask interlayer film is preferably 5 to 200 nm, more preferably 10 to 100 nm. The inorganic hard mask interlayer film is most preferably a SiON film which has a high effect as an antireflection film.

[0352] [Four-layer resist processing using an inorganic hard mask interlayer and an organic anti-reflection film or a bonding film]

[0353] Furthermore, the present invention provides a pattern forming method, characterized in that:

[0354] forming an organic film on a workpiece using the above-described composition for forming an organic film,

[0355] forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the aforementioned organic film,

[0356] forming an organic anti-reflection film or a bonding film on the inorganic hard mask intermediate film;

[0357] On the organic antireflection film or the adhesion film, a resist upper layer film is formed using a resist upper layer film material composed of a photoresist composition,

[0358] Forming a circuit pattern on the resist upper film,

[0359] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the inorganic hard mask intermediate film by etching.

[0360] The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0361] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0362] This method can be performed in the same manner as the above-mentioned three-layer resist process using an inorganic hard mask interlayer, except that an organic antireflection film (BARC) or a bonding film is formed between the inorganic hard mask interlayer and the resist upper layer film.

[0363] In particular, when a SiON film is used as an inorganic hard mask intermediate film, the two-layer antireflection film of the SiON film and the BARC can suppress reflection even in high NA immersion exposure exceeding 1.0. Another benefit of forming a BARC is that it has the effect of reducing the tailing of the resist upper film pattern directly on the SiON film.

[0364] Here, an example of the pattern forming method formed by three-layer resist processing of the present invention is shown in Figure 3 (A) to (F). In the case of 3-layer resist processing, Figure 3 As shown in (A), an organic film 3 is formed on a workpiece layer 2 formed on a substrate 1 using the composition for forming an organic film of the present invention, a silicon-containing resist intermediate film 4 is formed, and a resist upper film 5 is formed thereon. Figure 3 As shown in (B), the exposed portion 6 of the resist upper film 5 is exposed and PEB (post-exposure baking) is performed. Figure 3 As shown in (C), development is performed to form a resist upper film pattern 5a. Figure 3 As shown in (D), the resist upper film pattern 5a is used as a mask, and the silicon-containing resist intermediate film 4 is dry-etched using a fluorine-based gas to form a silicon-containing resist intermediate film pattern 4a. Figure 3 As shown in (E), after removing the resist upper film pattern 5a, the silicon-containing resist intermediate film pattern 4a is used as a mask, and the organic film 3 is etched by oxygen plasma to form an organic film pattern 3a. Figure 3 As shown in (F), after removing the silicon-containing resist intermediate film pattern 4a, the organic film pattern 3a is used as a mask and the processed layer 2 is etched to form a pattern 2a. Since the ridges are suppressed when the organic film is formed, Figure 3The dry etching process of (D), (E), and (F) can reduce defects caused by the protrusion of the organic film.

[0365] When forming an inorganic hard mask intermediate film, the silicon-containing resist intermediate film 4 may be replaced with an inorganic hard mask intermediate film, and when forming a BARC or a bonding film, the BARC or the bonding film may be formed between the silicon-containing resist intermediate film 4 and the resist upper film 5. The etching of the BARC or the bonding film may be performed before and continuously with the etching of the silicon-containing resist intermediate film 4, or the etching of the BARC or the bonding film may be performed only, and then the etching device may be changed and the etching of the silicon-containing resist intermediate film 4 may be performed.

[0366] As described above, according to the pattern forming method of the present invention, a fine pattern can be formed on a workpiece with high precision by multilayer resist processing, and the formation of ridges of an organic film can be suppressed to reduce defects caused by the ridges of the organic film.

[0367] [Example]

[0368] The following will show synthesis examples, comparative synthesis examples, embodiments and comparative examples to explain the present invention in more detail, but the present invention is not limited thereto. In addition, the molecular weight is specifically measured by the following method. The polystyrene-equivalent weight average molecular weight (Mw) and number average molecular weight (Mn) obtained by gel permeation chromatography (GPC) using tetrahydrofuran as an elution liquid (solvent) are obtained, and the dispersion degree (Mw / Mn) is obtained.

[0369] [Synthesis of polymers (A1) to (A8)]

[0370] In the synthesis of polymers (A1) to (A8) used in the preparation of the organic film-forming composition, octafluorocyclopentene and the following compounds (a1) to (a10) as diol, alcohol and carboxylic acid components were used.

[0371] [Chemistry 55]

[0372]

[0373] [Synthesis Example 1] Synthesis of polymer (A1)

[0374] [Chemistry 56]

[0375]

[0376] Under nitrogen atmosphere, 4.67 g of compound (a1) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to make a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and the mixture was reacted at room temperature for 24 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed twice with 50 g of 3.0% nitric acid aqueous solution and five times with 50 g of pure water, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure. After adjusting the concentration, a polymer (A1) was obtained in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0377] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0378] (A1): Mw=6,700, Mw / Mn=2.34

[0379] [Synthesis Example 2] Synthesis of polymer (A2)

[0380] [Chemistry 57]

[0381]

[0382] Under nitrogen atmosphere, 5.02 g of compound (a2) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to form a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and after reacting at room temperature for 16 hours, 1.02 g of compound (a8) was added dropwise, and further reacted for 8 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed once with 50 g of 3.0% sodium bicarbonate aqueous solution, 3 times with 50 g of 3.0% nitric acid aqueous solution, and 5 times with 100 g of pure water, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure and the concentration was adjusted to obtain a polymer (A2) in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0383] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0384] (A2): Mw=8,600, Mw / Mn=2.76

[0385] [Synthesis Example 3] Synthesis of polymer (A3)

[0386] [Chemistry 58]

[0387]

[0388] Under nitrogen atmosphere, 13.60 g of compound (a3) ​​and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to form a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and the mixture was reacted at room temperature for 24 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed twice with 50 g of 3.0% nitric acid aqueous solution and five times with 50 g of pure water, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure and the concentration was adjusted to obtain a polymer (A3) in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0389] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0390] (A3): Mw=12,800, Mw / Mn=3.21

[0391] [Synthesis Example 4] Synthesis of polymer (A4)

[0392] [Chemistry 59]

[0393]

[0394] Under nitrogen atmosphere, 6.12 g of compound (a4) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to form a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and the mixture was reacted at room temperature for 24 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed twice with 50 g of 3.0% nitric acid aqueous solution and five times with 50 g of pure water, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure and the concentration was adjusted to obtain a polymer (A4) in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0395] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0396] (A4): Mw=14,500, Mw / Mn=2.81

[0397] [Synthesis Example 5] Synthesis of polymer (A5)

[0398] [Chemistry 60]

[0399]

[0400] Under nitrogen atmosphere, 7.17 g of compound (a5) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to make a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and the mixture was reacted at room temperature for 24 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed twice with 50 g of 3.0% nitric acid aqueous solution and five times with 50 g of pure water, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure. After adjusting the concentration, a polymer (A5) was obtained in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0401] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0402] (A5): Mw=13,000, Mw / Mn=1.94

[0403] [Synthesis Example 6] Synthesis of polymer (A6)

[0404] [Chemistry 61]

[0405]

[0406] Under nitrogen atmosphere, 4.50 g of compound (a6) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to make a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and after reacting at room temperature for 16 hours, 6.67 g of compound (a9) was added dropwise and further reacted for 8 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed with 50 g of 3.0% sodium hydroxide aqueous solution twice, 50 g of 3.0% nitric acid aqueous solution three times, and 100 g of pure water five times, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure and the concentration was adjusted to obtain a polymer (A6) in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0407] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0408] (A6): Mw=11,100, Mw / Mn=2.75

[0409] [Synthesis Example 7] Synthesis of polymer (A7)

[0410] [Chemistry 62]

[0411]

[0412] Under nitrogen atmosphere, 10.08 g of compound (a7) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to make a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and the mixture was reacted at room temperature for 24 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and the mixture was washed twice with 50 g of 3.0% nitric acid aqueous solution and five times with 50 g of pure water, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure. After adjusting the concentration, a polymer (A7) was obtained in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0413] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0414] (A7): Mw=9,700, Mw / Mn=2.19

[0415] [Synthesis Example 8] Synthesis of polymer (A8)

[0416] [Chemistry 63]

[0417]

[0418] Under nitrogen atmosphere, 8.24 g of compound (a7) and 50.0 g of THF (tetrahydrofuran) were stirred in an ice bath to make a uniform solution, and then 2.72 g of sodium hydride was added and stirred for 1 hour. Then, a mixed solution of 10.0 g of octafluorocyclopentene and 10.0 g of THF was added dropwise over 20 minutes, and after reacting at room temperature for 16 hours, 1.70 g of compound (a10) was added dropwise, and the reaction was further reacted for 8 hours. After the reaction, 50 g of pure water was added dropwise to quench the reaction, 100 ml of MIBK was added, and the lower layer after separation was removed, and washed with 50 g of 2.0% nitric acid aqueous solution 3 times and with 100 g of pure water 5 times in sequence, and the organic layer was dried under reduced pressure. 50 g of THF was added to the residue, and 200 g of hexane was added dropwise while stirring to precipitate a sticky precipitate. After standing for a period of time, the transparent supernatant was decanted. 50 g of THF was added again to make a uniform solution, and 200 g of hexane was added to precipitate a sticky precipitate. After standing, the supernatant was decanted. PGMEA (propylene glycol monomethyl ether acetate) was added to the residue, and the mixture was distilled under reduced pressure. After adjusting the concentration, a polymer (A8) was obtained in the form of a PGMEA solution with a polymer concentration of 30 wt%.

[0419] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0420] (A8): Mw=10,200, Mw / Mn=3.04

[0421] [Synthesis of Comparative Polymers (R1) to (R5)]

[0422] In the synthesis of comparative polymers (R1) to (R5) used in the preparation of the organic film-forming composition, the following monomers (r1) to (r6) were used.

[0423] [Chemistry 64]

[0424]

[0425] [Comparative Synthesis Example 1] Synthesis of Comparative Polymer (R1)

[0426] [Chemistry 65]

[0427]

[0428] In a nitrogen atmosphere, 6.0 g of propylene glycol monomethyl ether acetate (PGMEA) was heated and stirred at 80°C. A mixture of 3.44 g (0.011 mol) of monomer (r1), 7.46 g (0.034 mol) of monomer (r3), 0.473 g of dimethyl 2,2-azobis(2-methylpropionic acid) and 34 g of PGMEA was added dropwise over 4 hours. After further heating and stirring for 16 hours, the mixture was cooled to room temperature to obtain a PGMEA solution of the target comparative polymer (R1).

[0429] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0430] (R1): Mw=9,500, Mw / Mn=1.20

[0431] [Comparative Synthesis Example 2] Synthesis of Comparative Polymer (R2)

[0432] [Chemistry 66]

[0433]

[0434] In a nitrogen atmosphere, 6.0 g of propylene glycol monomethyl ether acetate (PGMEA) was heated and stirred at 80°C. A mixture of 1.43 g (0.005 mol) of monomer (r1), 5.76 g (0.041 mol) of monomer (r4), 0.473 g of dimethyl 2,2-azobis(2-methylpropionic acid) and 34 g of PGMEA was added dropwise over 4 hours. After further heating and stirring for 16 hours, the mixture was cooled to room temperature to obtain a PGMEA solution of the target comparative polymer (R2).

[0435] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0436] (R2): Mw=5,800, Mw / Mn=1.42

[0437] [Comparative Synthesis Example 3] Synthesis of Comparative Polymer (R3)

[0438] [Chemistry 67]

[0439]

[0440] In a nitrogen atmosphere, 6.0 g of propylene glycol monomethyl ether acetate (PGMEA) was heated and stirred at 80°C. A mixture of 7.00 g (0.032 mol) of monomer (r2), 1.92 g (0.014 mol) of monomer (r4), 0.473 g of dimethyl 2,2-azobis(2-methylpropionic acid) and 34 g of PGMEA was added dropwise over 4 hours. After further heating and stirring for 16 hours, the mixture was cooled to room temperature to obtain a PGMEA solution of the target comparative polymer (R3).

[0441] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0442] (R3): Mw=6,200, Mw / Mn=1.33

[0443] [Comparative Synthesis Example 4] Synthesis of Comparative Polymer (R4)

[0444] [Chemistry 68]

[0445]

[0446] In a nitrogen atmosphere, 6.0 g of propylene glycol monomethyl ether acetate (PGMEA) was heated and stirred at 80°C. A mixture of 5.00 g (0.023 mol) of monomer (r2), 3.20 g (0.023 mol) of monomer (r5), 0.473 g of dimethyl 2,2-azobis(2-methylpropionate) and 34 g of PGMEA was added dropwise over 4 hours. After further heating and stirring for 16 hours, the mixture was cooled to room temperature to obtain a PGMEA solution of the target comparative polymer (R4).

[0447] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0448] (R4): Mw=8,300, Mw / Mn=1.33

[0449] [Comparative Synthesis Example 5] Synthesis of Comparative Polymer (R5)

[0450] [Chemistry 69]

[0451]

[0452] In a nitrogen atmosphere, 6.0 g of propylene glycol monomethyl ether acetate (PGMEA) was heated and stirred at 80°C. A mixture of 2.00 g (0.009 mol) of monomer (r2), 5.41 g (0.036 mol) of monomer (r6), 0.473 g of dimethyl 2,2-azobis(2-methylpropionic acid) and 34 g of PGMEA was added dropwise over 4 hours. After further heating and stirring for 16 hours, the mixture was cooled to room temperature to obtain a PGMEA solution of the target comparative polymer (R5).

[0453] The weight average molecular weight (Mw) and the degree of dispersion (Mw / Mn) were determined by GPC. The results are as follows.

[0454] (R5): Mw=3,800, Mw / Mn=1.44

[0455] The structural formula, weight average molecular weight (Mw) and dispersity (Mw / Mn) of the polymers (A1) to (A8) obtained above are listed in Tables 1 and 2. The structural formula, Mw and Mw / Mn of comparative polymers (R1) to (R5) used in comparative examples are also shown in Table 3.

[0456] [Table 1]

[0457]

[0458] [Table 2]

[0459]

[0460] [Table 3]

[0461]

[0462] [Organic film forming resin] B1: Resin represented by the following formula (B1) B2: Resin represented by the following formula (B2) B3: Compound represented by the following formula (B3) B4: Compound represented by the following formula (B4) B5: Resin represented by the following formula (B5) B6: Resin represented by the following formula (B6) [Chemical 70]

[0463]

[0464] [Solvent]

[0465] (C1): Propylene glycol monomethyl ether acetate (C2): Propylene glycol monoethyl ether

[0466] [Preparation of organic film-forming compositions (UDL-1 to 59, comparative UDL-1 to 11)]

[0467] The above-mentioned polymers (A1) to (A8), comparative polymers (R1) to (R5), organic film-forming resins (B1) to (B6), and solvents (C1) to (C2) were dissolved in the proportions shown in Tables 4 to 6, and filtered with a 0.1 μm fluororesin filter to obtain organic film-forming compositions (resist underlayer film materials: UDL-1 to 59, comparative UDL-1 to 11), respectively.

[0468] [Table 4]

[0469]

[0470] [Table 5]

[0471]

[0472] [Table 6]

[0473]

[0474] [Production of Silicon Wafer Having Formed an Organic Film Using the Composition for Forming an Organic Film (UDL-1 to 59, Comparative UDL-1 to 11)]

[0475] Using the coating / developing equipment "CLEAN TRACK LITHIUS Pro AP" of Tokyo Electron Co., Ltd., 2 ml of the organic film-forming composition (UDL-1 to 59, comparative UDL-1 to 11) prepared above was sprayed onto the center of the silicon wafer, and the wafer was spread by rotating at a rotation speed that would give the average film thickness described in Tables 7 to 9 after baking, thereby forming a film. While the silicon wafer was rotated at a speed of 1,000 rpm, the removal liquid spray nozzle was moved from the outer periphery of the silicon wafer toward the center at a speed of 5 mm / s to a position of 3 mm, and the removal liquid was further sprayed at a spray volume of 2 mL / s for 5 seconds at this position. Then, the spraying of the spray liquid was stopped, and the wafer was further rotated at a speed of 1,000 rpm for 30 seconds. Next, the silicon wafer on which the organic film-forming composition had been formed was heated at 350° C. for 60 seconds for curing, thereby obtaining a silicon wafer on which an organic film had been formed.

[0476] [Evaluation of Solvent Resistance: Examples 1-1 to 1-59, Comparative Examples 1-1 to 1-11]

[0477] The organic film-forming composition (UDL-1 to 59, comparative UDL-1 to 11) was formed into a film on a silicon wafer by the above method, and the film thickness was measured. PGMEA solvent was dispensed thereon, left for 30 seconds, and then spun dry, and baked at 100°C for 60 seconds to evaporate PGMEA, and the film thickness was measured. The film thickness before dispensing the PGMEA solvent was X, and the film thickness after dispensing the PGMEA solvent was X1. The absolute value of the value obtained by [(X1-X) / X]×100 was taken as the film thickness change rate (%). When the film thickness change rate was less than 0.5%, it was rated as good, and when it was more than 0.5%, it was rated as poor. The results are shown in Tables 7 to 9.

[0478] [Evaluation of In-Plane Uniformity: Examples 1-1 to 1-59, Comparative Examples 1-1 to 1-11]

[0479] The organic film-forming composition (UDL-1 to 59, comparative UDL-1 to 11) was formed on a silicon wafer by the above method, and the film thickness within a radius of 145 mm from the center of the organic film was measured, and the maximum film thickness was set to X max , the minimum film thickness is X min , the average film thickness is X average , will be represented by (X max -X min ) / X average The obtained value was defined as the in-plane uniformity (%). A (very good) was given when the in-plane uniformity was less than 2%, B (good) when it was 2% or more and less than 3%, and C (poor) when it was 3% or more. The results are shown in Tables 7 to 9.

[0480] [Table 7]

[0481] Organic film forming composition average film thickness Solvent resistance In-plane uniformity Example 1-1 UDL-1 500nm good A Example 1-2 UDL-2 500nm good A Examples 1-3 UDL-3 500nm good A Examples 1-4 UDL-4 500nm good A Examples 1-5 UDL-5 500nm good A Examples 1-6 UDL-6 500nm good A Examples 1-7 UDLv7 500nm good A Examples 1-8 UDL-8 500nm good A Examples 1-9 UDL-9 500nm good A Examples 1-10 UDL-10 500nm good A Embodiment 1-11 UDL-11 500nm good A Examples 1-12 UDL-12 500nm good A Examples 1-13 UDL-13 500nm good A Examples 1-14 UDL-14 500nm good A Examples 1-15 UDL-15 500nm good A Examples 1-16 UDL-16 500nm good A Examples 1-17 UDL-17 500nm good B Examples 1-18 UDL-18 500nm good A Examples 1-19 UDL-19 500nm good B Examples 1-20 UDL-20 500nm good A Embodiment 1-21 UDL-21 500nm good A Examples 1-22 UDL-22 500nm good A Examples 1-23 UDL-23 500nm good A Examples 1-24 UDL-24 500nm good A Examples 1-25 UDL-25 500nm good A Examples 1-26 UDL-26 500nm good A Examples 1-27 UDL-27 500nm good A Examples 1-28 UDL-28 500nm good A Examples 1-29 UDL-29 500nm good A Examples 1-30 UDL-30 500nm good A Example 1-31 UDL-31 500nm good A

[0482] [Table 8]

[0483] Organic film forming composition average film thickness Solvent resistance In-plane uniformity Example 1-32 UDL-32 500nm good A Examples 1-33 UDL-33 500nm good A Examples 1-34 UDL-34 500nm good A Embodiment 1-35 UDL-35 500nm good A Embodiment 1-36 UDL-36 500nm good A Example 1-37 UDL-37 500nm good A Examples 1-38 UDL-38 500nm good A Examples 1-39 UDL-39 500nm good A Embodiment 1-40 UDL-40 500nm good A Example 1-41 UDL-41 500nm good A Example 1-42 UDL-42 500nm good A Embodiment 1-43 UDL-43 500nm good A Embodiment 1-44 UDL-44 500nm good A Embodiment 1-45 UDL-45 500nm good A Embodiment 1-46 UDL-46 500nm good A Embodiment 1-47 UDL-47 500nm good A Examples 1-48 UDL-48 500nm good A Examples 1-49 UDL-49 500nm good A Embodiment 1-50 UDL-50 500nm good A Example 1-51 UDL-51 500nm good A Example 1.52 UDL-52 500nm good A Embodiment 1-53 UDL-53 500nm good A Embodiment 1-54 UDL-54 500nm good A Embodiment 1-55 UDL-55 500nm good A Example 1-56 UDL-56 500nm good A Example 1-57 UDL-57 500nm good A Embodiment 1-58 UDL-58 500nm good A Embodiment 1-59 UDL-59 500nm good A

[0484] [Table 9]

[0485] Organic film forming composition average film thickness Solvent resistance In-plane uniformity Comparative Example 1-1 Compare UDL-1 500nm good A Comparative Example 1-2 Compare UDL-2 500nm good A Comparative Examples 1-3 Compare UDL-3 500nm good A Comparative Examples 1-4 Compare UDL-4 500nm good A Comparative Examples 1-5 Compare UDL-5 500nm good A Comparative Examples 1-6 Compare UDL-6 500nm good C Comparative Examples 1-7 Compare UDL-7 500nm good C Comparative Examples 1-8 Compare UDL-8 500nm good C Comparative Examples 1-9 Compare UDL-9 500nm good C Comparative Examples 1-10 Compare UDL-10 500nm good C Comparative Examples 1-11 Compare UDL-11 500nm good C

[0486] [Evaluation of bulging suppression property: Examples 2-1 to 2-59, Comparative Examples 2-1 to 2-5]

[0487] The organic film-forming composition (UDL-1 to 59, comparative UDL-1 to 5) was formed on a silicon wafer by the above method, and then the height change from the outer peripheral edge of the organic film to the position of 1,000 μm in the direction of the center of the silicon wafer was measured using Alpha-Step D-600 (contact profiler) manufactured by KLA-TENCOR. When the height of the silicon wafer is 0, Figure 1As shown in the figure, the case where the maximum height does not reach 110% of the film thickness is rated as A (very good), and the case where the maximum height is more than 110% but less than 150% is rated as B (good). Figure 2 The case where a region with a height of 150% or more was generated was rated as C (bad). The results are shown in Tables 10 to 12.

[0488] [Landfill evaluation: Examples 2-1 to 2-59, Comparative Examples 2-1 to 2-5]

[0489] like Figure 4 On a SiO2 wafer substrate having a dense hole pattern (hole diameter 0.2 μm, hole depth 1.0 μm, distance between the centers of two adjacent holes 0.4 μm), the organic film forming composition (UDL-1 to 59, comparative UDL-1 to 5) was formed by the above method to form an organic film 8. The substrate used was as follows Figure 4 The base substrate (SiO2 wafer substrate) 7 with a dense hole pattern shown in (G) (bird's-eye view) and (H) (cross-sectional view). The cross-sectional shape of each wafer substrate obtained was observed using a scanning electron microscope (SEM) to confirm whether the pores were filled with organic film without voids. When an organic film-forming composition with poor filling characteristics is used, voids will be generated inside the pores. When an organic film-forming composition with good filling characteristics is used, in this evaluation, Figure 4 As shown in (I), the pores were filled with the organic film 8 without voids. The case where no voids were generated was rated as good, and the case where voids were generated was rated as poor. The results are shown in Tables 10 to 12.

[0490] [Table 10]

[0491] Organic film forming composition Evaluation of heave inhibition Landfill characteristics evaluation Example 2-1 UDL-1 A good Example 2-2 UDL-2 B good Example 2-3 UDL-3 B good Embodiment 2-4 UDL-4 B good Embodiment 2-5 UDL-5 A good Embodiment 2-6 UDL-6 B good Embodiment 2-7 UDL-7 A good Embodiment 2-8 UDL-8 A good Embodiment 2-9 UDL-9 A good Embodiment 2-10 UDL-10 B good Example 2-11 UDL-11 B good Example 2-12 UDL-12 B good Example 2-13 UDL-13 A good Embodiment 2-14 UDL-14 B good Example 2-15 UDL-15 A good Example 2-16 UDL-16 A good Example 2-17 UDL-17 A good Example 2-18 UDL-18 A good Example 2-19 UDL-19 A good Embodiment 2-20 UDL-20 A good Example 2-21 UDL-21 B good Example 2-22 UDL-22 B good Example 2-23 UDL-23 B good Example 2-24 UDL-24 A good Example 2-25 UDL-25 B good Example 2-26 UDL-26 A good Example 2-27 UDL-27 A good Example 2-28 UDL-28 A good Example 2-29 UDL-29 B good Example 2-30 UDL-30 B good Example 2-31 UDL-31 B good

[0492] [Table 11]

[0493] Organic film forming composition Evaluation of heave inhibition Landfill characteristics evaluation Example 2-32 UDL-32 A good Example 2-33 UDL-33 B good Example 2-34 UDL-34 A good Example 2-35 UDL-35 A good Example 2-36 UDL-36 A good Example 2-37 UDL-37 B good Example 2-38 UDL-38 B good Example 2-39 UDL-39 B good Example 2-40 UDL-40 A good Example 2-41 UDL-41 B good Example 2-42 UDL-42 A good Example 2-43 UDL-43 A good Example 2-44 UDL-44 A good Example 2-45 UDL-45 B good Example 2-46 UDL-46 B good Example 2-47 UDL-47 B good Example 2-48 UDL-48 A good Example 2-49 UDL-49 B good Example 2-50 UDL-50 A good Example 2-51 UDL-51 A good Example 2-52 UDL-52 A good Example 2-53 UDL-53 B good Example 2-54 UDL-54 B good Example 2-55 UDL-55 B good Example 2-56 UDL-56 A good Example 2-57 UDL-57 B good Example 2-58 UDL-58 A good Example 2-59 UDL-59 A good

[0494] [Table 12]

[0495] Organic film forming composition Evaluation of heave inhibition Landfill characteristics evaluation Comparative Example 2-1 Compare UDL-1 C bad Comparative Example 2-2 Compare UDL-2 C bad Comparative Example 2-3 Compare UDL-3 C bad Comparative Examples 2-4 Compare UDL-4 C bad Comparative Examples 2-5 Compare UDL-5 A bad

[0496] As shown in Tables 7 to 12, it was confirmed that the organic film-forming compositions of the present invention (UDL-1 to 59) were excellent in solvent resistance, in-plane uniformity, swelling suppression, and filling characteristics.

[0497] On the other hand, it was confirmed that the comparative UDL-1 to 11 which did not use the organic film-forming composition of the present invention had poor results in any one or more of solvent resistance, in-plane uniformity, swelling suppression, and filling characteristics.

[0498] [Pattern Formation Test: Examples 3-1 to 3-59]

[0499] An organic film was formed on a SiO2 wafer substrate using an organic film forming composition (UDL-1 to 59) in the above method, and the following silicon-containing resist intermediate film material (SOG1) was coated thereon and baked at 200°C for 60 seconds to form a silicon-containing resist intermediate film with a film thickness of 35nm. The following ArF single-layer resist was coated thereon as a resist upper film material and baked at 105°C for 60 seconds to form a photoresist film with a film thickness of 100nm. The following wet protection film material (TC-1) was coated on the photoresist film and baked at 90°C for 60 seconds to form a protection film with a film thickness of 50nm.

[0500] As for the silicon-containing resist interlayer material (SOG1), a 2% solution of the following polymer in propylene glycol ethyl ether was prepared.

[0501] [Chemistry 71]

[0502]

[0503] As for the resist upper layer film material (single-layer resist for ArF), it is obtained by dissolving a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) in a ratio as shown in Table 13 in a solvent containing 0.1 mass% of FC-430 (manufactured by Sumitomo 3M Co., Ltd.) and filtering with a 0.1 μm fluororesin filter.

[0504] [Table 13]

[0505]

[0506] The polymer (RP1), the acid generator (PAG1) and the basic compound (Amine1) are shown below.

[0507] [Chemistry 72]

[0508]

[0509] The wet protective film material (TC-1) was prepared by dissolving the polymer (PP1) in an organic solvent at the ratio shown in Table 14 and filtering the solution with a 0.1 μm fluororesin filter.

[0510] [Table 14]

[0511]

[0512] The polymer (PP1) is shown below.

[0513] [Chemistry 73]

[0514]

[0515] Next, the film was exposed using an ArF immersion exposure apparatus (manufactured by Nikon Co., Ltd.; NSR-S610C, NA1.30, σ0.98 / 0.65, 35-degree dipole s-polarized illumination, 6% half-step phase shift mask), baked at 100°C for 60 seconds (PEB), and developed with a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 55nm 1:1 positive line and space pattern (resist upper film pattern).

[0516] Next, the resist upper film pattern is used as a mask, and the etching device Telius manufactured by Tokyo Electron is used to perform dry etching processing (pattern transfer) on the silicon-containing resist intermediate film, and the obtained silicon-containing resist intermediate film pattern is used as a mask to perform dry etching processing (pattern transfer) on the organic film, and the obtained organic film pattern is used as a mask to perform dry etching processing (pattern transfer) on the SiO2 wafer substrate (SiO2 film). The etching conditions are as follows.

[0517] (Etching conditions when transferring the resist upper layer film pattern to the silicon-containing resist intermediate film)

[0518]

[0519]

[0520] (Etching conditions when transferring the silicon-containing resist interlayer film pattern to the organic film)

[0521]

[0522] (Etching conditions when transferring organic film patterns to SiO2 wafer substrates)

[0523]

[0524] The cross section of the obtained pattern was observed with an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Tables 15 and 16.

[0525] [Table 15]

[0526] Organic film forming composition Substrate transfer etching shape Example 3-1 UDL-1 good Example 3-2 UDL-2 good Example 3-3 UDL-3 good Embodiment 3-4 UDL-4 good Embodiment 3-5 UDL-5 good Embodiment 3-6 UDL-6 good Embodiment 3-7 UDL-7 good Embodiment 3-8 UDL-8 good Embodiment 3-9 UDL-9 good Embodiment 3-10 UDL-10 good Example 3-11 UDL-11 good Example 3-12 UDL-12 good Example 3-13 UDL-13 good Embodiment 3-14 UDL-14 good Example 3-15 UDL-15 good Example 3-16 UDL-16 good Example 3-17 UDL-17 good Example 3-18 UDL-18 good Example 3-19 UDL-19 good Example 3-20 UDL-20 good Example 3-21 UDL-21 good Example 3-22 UDL-22 good Example 3-23 UDL-23 good Example 3-24 UDL-24 good Example 3-25 UDL-25 good Example 3-26 UDL-26 good Example 3-27 UDL-27 good Example 3-28 UDL-28 good Example 3-29 UDL-29 good Example 3-30 UDL-30 good Example 3-31 UDL-31 good

[0527] [Table 16]

[0528] Organic film forming composition Substrate transfer etching shape Example 3-32 UDL-32 good Example 3-33 UDL-33 good Example 3-34 UDL-34 good Example 3-35 UDL-35 good Example 3-36 UDL-36 good Example 3-37 UDL-37 good Example 3-38 UDL-38 good Example 3-39 UDL-39 good Example 3-40 UDL-40 good Example 3-41 UDL-41 good Example 3-42 UDL-42 good Example 3-43 UDL-43 good Example 3-44 UDL-44 good Example 3-45 UDL-45 good Example 3-46 UDL-46 good Example 3-47 UDL-47 good Example 3-48 UDL-48 good Embodiment 3-49 UDL-49 good Example 3-50 UDL-50 good Example 3-51 UDL-51 good Example 3-52 UDL-52 good Example 3-53 UDL-53 good Example 3-54 UDL-54 good Example 3-55 UDL-55 good Example 3-56 UDL-56 good Example 3-57 UDL-57 good Example 3-58 UDL-58 good Example 3-59 UDL-59 good

[0529] As shown in Tables 15 and 16, in Examples 3-1 to 3-59 using the organic film forming composition (UDL-1 to 59) of the present invention, the resist upper film pattern was ultimately well transferred to the SiO2 wafer substrate, confirming that the organic film forming composition of the present invention can be ideally used in micro-processing performed by the multilayer resist method.

[0530] From the above, it can be seen that if the organic film forming composition of the present invention is used, it will have excellent film-forming properties and high filling characteristics and ridge suppression properties, so it is extremely useful as an organic film material used for multilayer anti-etching processing; furthermore, if the pattern forming method of the present invention uses the organic film forming composition, since it can form an organic film that can fill holes and trenches with very high aspect ratios without gaps and can form fine patterns with high precision and has suppressed ridges, it is possible to efficiently manufacture semiconductor elements, etc.

[0531] This specification covers the following aspects.

[0532] [1]: A composition for forming an organic film, characterized in that it comprises: (A) a polymer having a repeating unit represented by the following general formula (1), (B) a resin for forming an organic film, and (C) a solvent;

[0533] [Chemistry 74]

[0534]

[0535] In the general formula (1), R is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.

[0536] [2]: The organic film-forming composition according to [1] above, wherein the polymer (A) is any one or more of the following general formulas (2) to (4);

[0537] [Chemistry 75]

[0538]

[0539] In the formula, R1 is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms and may have an ether bond; R2 is a monovalent organic group having 1 to 30 carbon atoms; and n represents the average number of repeating units and is 3 to 2,000.

[0540] [3]: The organic film-forming composition according to [1] or [2], wherein the content of the polymer (A) is 0.01 to 5 parts by mass based on 100 parts by mass of the organic film-forming resin (B).

[0541] [4]: A method for forming an organic film, which is a method for forming an organic film used in the manufacturing steps of a semiconductor device, characterized in that: an organic film forming composition as described in any one of [1] to [3] above is spin-coated on a substrate to be processed, and the substrate coated with the organic film forming composition is heat-treated at a temperature of not less than 100°C and not more than 600°C and within a range of 10 to 600 seconds to harden the substrate, thereby forming an organic film.

[0542] [5]: A pattern forming method, characterized by:

[0543] Forming an organic film on a workpiece using the organic film-forming composition described in any one of [1] to [3] above,

[0544] A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material.

[0545] A resist upper layer film is formed on the silicon-containing resist intermediate film using a resist upper layer film material composed of a photoresist composition.

[0546] Forming a circuit pattern on the resist upper film,

[0547] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the silicon-containing resist intermediate film by etching.

[0548] The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0549] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0550] [6]: A pattern forming method, characterized by:

[0551] Forming an organic film on a workpiece using the organic film-forming composition described in any one of [1] to [3] above,

[0552] A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material.

[0553] forming an organic antireflection film or a close-fitting film on the aforementioned silicon-containing resist intermediate film,

[0554] On the organic antireflection film or the adhesion film, a resist upper layer film is formed using a resist upper layer film material composed of a photoresist composition,

[0555] Forming a circuit pattern on the resist upper film,

[0556] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the silicon-containing resist intermediate film by etching.

[0557] The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0558] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0559] [7]: A pattern forming method, characterized by:

[0560] Forming an organic film on a workpiece using the organic film-forming composition described in any one of [1] to [3] above,

[0561] forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the aforementioned organic film,

[0562] A resist upper layer film is formed on the inorganic hard mask intermediate film using a resist upper layer film material composed of a photoresist composition,

[0563] forming a circuit pattern on the resist upper film,

[0564] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the inorganic hard mask intermediate film by etching.

[0565] The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0566] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0567] [8]: A pattern forming method, characterized by:

[0568] Forming an organic film on a workpiece using the organic film-forming composition described in any one of [1] to [3] above,

[0569] forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the aforementioned organic film,

[0570] forming an organic anti-reflection film or a bonding film on the inorganic hard mask intermediate film;

[0571] On the organic antireflection film or the adhesion film, a resist upper layer film is formed using a resist upper layer film material composed of a photoresist composition,

[0572] forming a circuit pattern on the resist upper film,

[0573] The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the inorganic hard mask intermediate film by etching.

[0574] The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching.

[0575] Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

[0576] [9]: The pattern forming method according to [7] or [8], wherein the inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

[0577]

[10] : A pattern forming method as described in any one of [5] to [9] above, wherein, when forming the aforementioned circuit pattern, the circuit pattern is formed by photolithography using light with a wavelength of greater than 10 nm and less than 300 nm, direct drawing using an electron beam, nanoimprinting, or a combination thereof.

[0578]

[11] : The pattern forming method according to any one of [5] to

[10] , wherein, when forming the circuit pattern, the circuit pattern is developed using an alkali developer or an organic solvent.

[0579]

[12] : A pattern forming method as described in any one of [5] to

[11] above, wherein a semiconductor device substrate or a substrate obtained by forming any one of a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxide carbide film and a metal oxide nitride film on the semiconductor device substrate is used as the processed body.

[0580]

[13] : A pattern forming method as described in

[12] above, wherein silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum or an alloy thereof is used as the metal constituting the aforementioned processed body.

[0581] The present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any device having substantially the same configuration and exhibiting the same functions and effects as the technical concept described in the claims of the present invention is within the technical scope of the present invention.

[0582] Description of Reference Numerals

[0583] 1:Substrate

[0584] 2: Processing layer

[0585] 2a: Pattern (pattern formed on the processed layer)

[0586] 3: Organic film

[0587] 3a: Organic film pattern

[0588] 4: Silicon-containing resist interlayer

[0589] 4a: Silicon-containing resist interlayer pattern

[0590] 5: Resist upper film

[0591] 5a: Resist upper film pattern

[0592] 6: Exposure part

[0593] 7: Base substrate

[0594] 8: Organic film

Claims

1. A composition for forming an organic film, characterized in that it comprises: (A) a polymer having a repeating unit represented by the following general formula (1), (B) an organic film-forming resin, and (C) a solvent; [Chemistry 1] In the general formula (1), R is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.

2. The organic film-forming composition according to claim 1, wherein The polymer (A) is any one or more of the following general formulas (2) to (4); [Chemistry 2] In the formula, R1 is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms and may have an ether bond; R2 is a monovalent organic group having 1 to 30 carbon atoms; and n represents the average number of repeating units and is 3 to 2,000.

3. The organic film-forming composition according to claim 1, wherein The content of the (A) polymer is 0.01 to 5 parts by mass based on 100 parts by mass of the (B) organic film-forming resin.

4. A method for forming an organic film, which is a method for forming an organic film used in a manufacturing step of a semiconductor device, characterized in that: The organic film is formed by spin-coating the organic film forming composition according to any one of claims 1 to 3 on a substrate to be processed, and heat-treating the substrate coated with the organic film forming composition at a temperature of 100° C. to 600° C. for 10 to 600 seconds to cure the substrate.

5. A pattern forming method, characterized in that: Forming an organic film on a workpiece using the organic film-forming composition according to any one of claims 1 to 3, A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material. A resist upper layer film is formed on the silicon-containing resist intermediate film using a resist upper layer film material composed of a photoresist composition. A circuit pattern is formed on the upper layer of the resist. The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the silicon-containing resist intermediate film by etching. The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching. Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

6. A pattern forming method, characterized in that: Forming an organic film on a workpiece using the organic film-forming composition according to any one of claims 1 to 3, A silicon-containing resist interlayer film is formed on the organic film using a silicon-containing resist interlayer film material. forming an organic antireflection film or an adhesion film on the silicon-containing resist intermediate film, forming a resist upper layer film on the organic antireflection film or the adhesion film using a resist upper layer film material composed of a photoresist composition, A circuit pattern is formed on the upper layer of the resist. The resist upper layer film having the circuit pattern formed thereon is used as a mask to transfer the pattern to the organic antireflection film or the adhesion film and the silicon-containing resist intermediate film by etching. The silicon-containing resist intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching. Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

7. A pattern forming method, characterized in that: Forming an organic film on a workpiece using the organic film-forming composition according to any one of claims 1 to 3, forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the organic film, A resist upper layer film is formed on the inorganic hard mask intermediate film using a resist upper layer film material composed of a photoresist composition. A circuit pattern is formed on the upper layer of the resist. The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the inorganic hard mask intermediate film by etching. The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching. Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

8. A pattern forming method, characterized in that: Forming an organic film on a workpiece using the organic film-forming composition according to any one of claims 1 to 3, forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film and a silicon oxide nitride film on the organic film, forming an organic anti-reflection film or a bonding film on the inorganic hard mask intermediate film, forming a resist upper layer film on the organic antireflection film or the adhesion film using a resist upper layer film material composed of a photoresist composition, A circuit pattern is formed on the upper layer of the resist. The resist upper layer film having the circuit pattern formed thereon is used as a mask and the pattern is transferred to the organic antireflection film or the adhesion film and the inorganic hard mask intermediate film by etching. The inorganic hard mask intermediate film having the transferred pattern is used as a mask and the pattern is transferred to the organic film by etching. Furthermore, the pattern is transferred to the object to be processed by etching using the organic film to which the pattern is transferred as a mask.

9. The pattern forming method according to claim 7, wherein: The inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

10. The pattern forming method according to claim 5, wherein: When forming the circuit pattern, the circuit pattern is formed by photolithography using light with a wavelength of 10 nm to 300 nm, direct drawing using an electron beam, nanoimprinting, or a combination thereof.

11. The pattern forming method according to claim 5, wherein: When forming the circuit pattern, the circuit pattern is developed using an alkali developer or an organic solvent.

12. The pattern forming method according to claim 5, wherein: As the workpiece, a semiconductor device substrate or a substrate obtained by forming a metal film, a metal carbide film, a metal oxide film, a metal nitride film, a metal oxide carbide film and a metal oxide nitride film on the semiconductor device substrate is used.

13. The pattern forming method according to claim 12, wherein: As the metal constituting the object to be processed, silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, molybdenum, or an alloy thereof is used.

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