Pattern Formation Method

Abstract

To provide a composition for forming an organic film, which uses a polymer containing an imide group and can form an organic underlay film curable even under a film-forming condition not only in air but also in an inactive gas, not producing by-products, not only high in heat-resistance and excellent in burying and flattening characteristics of a pattern formed on a substrate but also highly adhesive to the substrate, a substrate for manufacturing a semiconductor device, a method for forming an organic film, and a method for forming a pattern.SOLUTION: A material for forming an organic film contains: (A) a polymer having a repeating unit represented by general Formula (1A) and represented at a terminal group by general Formula; and (B) an organic solvent. (In the Formula, W1 is a tetravalent organic group, and W2 is a bivalent organic film).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a material for forming an organic film used in a semiconductor device manufacturing process, a substrate for manufacturing a semiconductor device using said material, a method for forming an organic film, and a method for forming a pattern by a multilayer resist method. [Background technology]

[0002] Conventionally, the high integration and high speed of semiconductor devices have been achieved by miniaturizing the pattern dimensions by shortening the wavelength of the light source in the lithography technology (photolithography) using light exposure as a general-purpose technology. In order to form such fine circuit patterns on a semiconductor device substrate (substrate to be processed), a method is used in which the substrate to be processed is processed by dry etching using a photoresist film on which a pattern is usually formed as an etching mask. However, in reality, there is no dry etching method that can achieve perfect etching selectivity between the photoresist film and the substrate to be processed, so in recent years, substrate processing using a multilayer resist method has become common. In this method, an intermediate film with etching selectivity different from the photoresist film (hereinafter referred to as the resist upper layer film) is interposed between the resist upper layer film and the substrate to be processed, and after obtaining a pattern on the resist upper layer film, the pattern is transferred to the intermediate film by dry etching using the resist upper layer film pattern as a dry etching mask, and the pattern is further transferred to the substrate to be processed by dry etching using the intermediate film as a dry etching mask.

[0003] One of the multilayer resist methods is a three-layer resist method that can be performed using a general resist composition used in a single-layer resist method. In this method, an organic underlayer film (hereinafter referred to as an organic film) is formed on a substrate to be processed by applying and baking an organic underlayer film material made of an organic resin-containing composition, and a silicon-containing film (hereinafter referred to as a silicon intermediate film) is formed on the organic underlayer film by applying and baking a resist intermediate film material made of a silicon-containing resin-containing composition on the organic underlayer film, and a general organic photoresist film (hereinafter referred to as a resist upper layer film) is formed on the organic underlayer film. After patterning the resist upper layer film, dry etching with fluorine-based gas plasma is performed, and the organic resist upper layer film can have a good etching selectivity to the silicon intermediate film, so the resist upper layer film pattern can be transferred to the silicon intermediate film. According to this method, even if a resist upper layer film that does not have a sufficient film thickness to directly process the substrate to be processed or a resist upper layer film that does not have sufficient dry etching resistance to process the substrate to be processed is used, the silicon intermediate film usually has a film thickness equal to or less than that of the resist upper layer film, so that the pattern can be easily transferred to the silicon intermediate film. Subsequently, by using the silicon intermediate film to which the pattern has been transferred as a dry etching mask to transfer the pattern to the organic underlayer film by dry etching with oxygen- or hydrogen-based gas plasma, the pattern can be transferred to the organic underlayer film that has sufficient dry etching resistance for processing the substrate. This organic underlayer film pattern to which the pattern has been transferred can be transferred to the substrate by dry etching using a fluorine-based gas or a chlorine-based gas.

[0004] On the other hand, miniaturization in the manufacturing process of semiconductor devices is approaching an essential limit due to the wavelength of the light source for photolithography. Therefore, in recent years, high integration of semiconductor devices without relying on miniaturization has been considered, and as one of the methods, semiconductor devices having complex structures such as multi-gate structures have been considered, and some have already been put to practical use. When such a structure is formed by the multi-layer resist method, an organic film material can be applied that can fill micropatterns such as holes, trenches, and fins formed on the substrate to be processed with a film without gaps, or fill steps, densely patterned areas, and areas without patterns with a film to perform planarization. By forming a flat organic underlayer film surface on a stepped substrate using such an organic film material, it is possible to suppress the film thickness fluctuation of the silicon intermediate film and resist upper layer film formed thereon, and to suppress the focal tolerance of photolithography and the margin reduction in the subsequent processing process of the substrate to be processed. This makes it possible to manufacture semiconductor devices with a high yield. On the other hand, in the single-layer resist method, in order to fill in steps or patterns on a processed substrate, the thickness of the top-layer resist film must be thick, which can lead to pattern collapse after exposure and development, or deterioration of the pattern shape due to reflection from the substrate during exposure, etc., and this narrows the pattern formation tolerance during exposure, making it difficult to manufacture semiconductor devices with a good yield.

[0005] Furthermore, as a method for increasing the speed of next-generation semiconductor devices, the application of precision materials such as new materials with high electron mobility using, for example, strained silicon or gallium arsenide, and ultra-thin polysilicon controlled in angstrom units has begun to be considered. However, in the case of a substrate to be processed to which such a new precision material is applied, the material is corroded by oxygen in the air under the conditions for forming a planarization film using the organic underlayer material described above, for example, under film formation conditions in air at 300° C. or higher, and the semiconductor device cannot achieve the performance as designed for the high speed operation, and there is a possibility that the yield rate for industrial production cannot be achieved. Therefore, in order to avoid the decrease in yield caused by the corrosion of the substrate by air under such high temperature conditions, an organic underlayer material that can be formed in an inert gas is expected.

[0006] Conventionally, condensation resins using carbonyl compounds such as ketones and aldehydes or aromatic alcohols as condensation agents for phenolic or naphtholic compounds are known as organic film forming materials for multilayer resist methods. For example, fluorene bisphenol novolac resin described in Patent Document 1, bisphenol compounds and their novolac resins described in Patent Document 2, adamantane phenol compound novolac resins described in Patent Document 3, and bisnaphthol compounds and their novolac resins described in Patent Document 4 can be exemplified. Such materials are formed as a film having solvent resistance against coating film materials used in the next process by crosslinking with a methylol compound as a crosslinking agent, or by a curing action caused by oxidation at the α-position of the aromatic ring due to the action of oxygen in the air and a crosslinking reaction caused by condensation thereafter.

[0007] Furthermore, materials that use triple bonds as intermolecular crosslinking groups of curable resins are known. For example, Patent Documents 5 to 11 are known. In these materials, a cured film having solvent resistance is formed by crosslinking due to polymerization of triple bonds as well as crosslinking derived from methylol as described above. However, these organic film-forming materials do not have sufficient embedding properties or planarization properties for patterns formed on a substrate.

[0008] Furthermore, as examples of materials having an imide structure as described in the present invention, resins having a polyimide structure as described in Patent Document 12 and Patent Document 13, and Patent Document 14 using a compound having a bismaleimide structure are known; however, there are no examples of terminal substituents having a triple bond on a nitrogen atom for these materials, and nothing is known about the formation of a cured film in an inert gas, film thickness fluctuation due to thermal decomposition under high temperature conditions, filling properties, planarization properties, and the like. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2005-128509 A [Patent Document 2] JP 2006-293298 A [Patent Document 3] JP 2006-285095 A [Patent Document 4] JP 2010-122656 A [Patent Document 5] JP 2010-181605 A [Patent Document 6] WO2014-208324 [Patent Document 7] JP 2012-215842 A [Patent Document 8] JP 2016-044272 A [Patent Document 9] JP 2016-060886 A [Patent Document 10] JP 2017-119671 A [Patent Document 11] JP 2013-83939 A [Patent Document 12] JP 2013-137334 A [Patent Document 13] JP 2010-122297 A [Patent Document 14] WO2018-212116 Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an organic film-forming material using a polymer containing an imide group, which is cured not only in air but also under film-forming conditions in an inert gas, does not generate by-products, and is excellent in heat resistance, and in filling and planarizing properties of a pattern formed on a substrate, as well as capable of forming an organic underlayer film having good adhesion to the substrate; and a substrate for manufacturing a semiconductor device, which uses the material, a method for forming an organic film, and a method for forming a pattern. [Means for solving the problem]

[0011] In order to achieve the above object, the present invention provides a material for forming an organic film, the material comprising: (A) a polymer having a repeating unit represented by the following general formula (1A) and an end group represented by either of the following general formulas (1B) and (1C); and (B) an organic solvent. [ka] (In the formula, W 1 is a tetravalent organic group, and W 2 is a divalent organic group. [ka] [ka] (In the formula, R 1 is any one of the groups represented by the following formula (1D), and two or more R 1 may be used in combination.) [ka]

[0012] Such an organic film-forming material can be cured not only in air but also under film-forming conditions in an inert gas due to the action of the terminal crosslinking group, and since the main chain is composed of a polyimide skeleton, it can form an organic film that has high heat resistance, good adhesion to the substrate, and advanced filling / planarization properties.

[0013] In addition, W in the general formula (1A) 1 is preferably a group represented by the following general formula (1E). [ka] (In the formula, W 3 is a single bond or a divalent organic group, which may have a substituent on the benzene ring in the formula, and W 3 The organic groups in may be bonded to form a cyclic organic group.

[0014] It is preferable for the main chain to have such a partial structure in order to impart excellent heat resistance.

[0015] In addition, W in the general formula (1A) 1 is preferably any one of groups represented by the following formula (1F). [ka] (The aromatic ring in the above formula may have a substituent.)

[0016] It is preferable for the main chain to have such a partial structure in terms of achieving both heat resistance and thermal fluidity.

[0017] In addition, W in the general formula (1A) 2 is preferably a group represented by the following general formula (1G). [ka] (In the formula, W 4 is a single bond or a divalent organic group, which may have a substituent on the benzene ring in the formula, and W 4 The organic groups in may be bonded to form a cyclic organic group.

[0018] It is preferable for the main chain to have such a partial structure in order to impart excellent heat resistance.

[0019] In addition, W in the general formula (1A) 2 is preferably any one of groups represented by the following formula (1H). [ka] (The aromatic ring in the above formula may have a substituent.)

[0020] It is preferable for the main chain to have such a partial structure in terms of achieving both heat resistance and thermal fluidity.

[0021] In addition, W in the general formula (1A) 1 is at least one of the groups represented by the formula (1F), and W in the general formula (1A) 2 is preferably one or more of the groups represented by the above formula (1H).

[0022] W 1 and W 2 However, by combining the above organic groups, it is possible to improve the thermal fluidity, heat resistance and adhesion.

[0023] The weight average molecular weight of the component (A) is preferably 1,000 to 10,000.

[0024] An organic film-forming material containing a polymer having an Mw in this range does not impair solubility in an organic solvent and can suppress outgassing during baking.

[0025] Moreover, the component (B) is preferably a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher.

[0026] In the case of such an organic film-forming material, the addition of a high-boiling point solvent to the above polymer gives the material film thermal fluidity, so that the material has both high-level filling and planarizing properties.

[0027] It is preferable that the organic film-forming material further contains one or more of (C) an acid generator, (D) a surfactant, (E) a crosslinking agent, and (F) a plasticizer.

[0028] An organic film-forming material containing such a component can be made to have superior coating properties or filling / planarizing properties.

[0029] The present invention also provides a substrate for manufacturing a semiconductor device, which comprises a substrate on which an organic film is formed by curing the above-mentioned organic film-forming material.

[0030] If the organic film is formed from the organic film-forming material of the present invention, it will have high filling / planarization properties, and will be an organic film that is free of microvoids due to insufficient filling or unevenness on the organic film surface due to insufficient flatness. A substrate for manufacturing a semiconductor device that is planarized with such an organic film will have a wide process margin during patterning, making it possible to manufacture semiconductor devices with a high yield.

[0031] The present invention also provides a method for forming an organic film that is applied in the manufacturing process of a semiconductor device, which comprises spin-coating the above-mentioned organic film-forming material onto a substrate to be processed, and then heat-treating the substrate to which the organic film-forming material has been applied in an inert gas atmosphere at a temperature of 50°C or higher and 600°C or lower for a period of 10 to 7200 seconds to obtain a cured film.

[0032] Furthermore, the present invention provides a method for forming an organic film that is applied in a manufacturing process of a semiconductor device, which comprises spin-coating the above-mentioned organic film-forming material onto a substrate to be processed, heat-treating the substrate to which the organic film-forming material has been applied in air at a temperature of 50°C or higher and 250°C or lower for a period of 5 to 600 seconds to form a coating film, and subsequently subjecting the substrate to a heat treatment in an inert gas atmosphere at a temperature of 200°C or higher and 600°C or lower for a period of 10 to 7200 seconds to obtain a cured film.

[0033] The organic film formed by the method of the present invention and applied in the manufacturing process of a semiconductor device has high heat resistance and advanced filling / planarization properties, and when used in the manufacturing process of a semiconductor device, the yield of the semiconductor device is improved.

[0034] At this time, it is preferable that the oxygen concentration in the inert gas is 1% or less.

[0035] The organic film-forming material of the present invention can be sufficiently cured without generating sublimates even when heated in such an inert gas atmosphere, and can form an organic film that has excellent adhesion to the substrate.

[0036] Furthermore, the substrate to be processed may have a structure or steps with a height of 30 nm or more.

[0037] The method for forming an organic film of the present invention is particularly useful for forming a flat organic film on such a substrate.

[0038] The present invention also provides a pattern forming method, which includes forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming a silicon-containing resist intermediate film on the organic film using a silicon-containing resist intermediate film material, forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist composition, forming a circuit pattern on the resist upper layer film, transferring the pattern to the silicon-containing resist intermediate film by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film to which the pattern has been transferred as a mask.

[0039] Furthermore, the present invention provides a pattern forming method, which comprises forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming a silicon-containing resist intermediate film on the organic film using a silicon-containing resist intermediate film material, forming an organic antireflective film on the silicon-containing resist intermediate film, forming a resist upper layer film on the organic antireflective film using a photoresist composition to form a four-layer film structure, forming a circuit pattern on the resist upper layer film, transferring the pattern to the organic antireflective film and the silicon-containing resist intermediate film by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film to which the pattern has been transferred as a mask.

[0040] Furthermore, the present invention provides a pattern formation method, which comprises forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a titanium oxide film, and a titanium nitride film on the organic film, forming a resist upper layer film on the inorganic hard mask using a photoresist composition, forming a circuit pattern on the resist upper layer film, transferring the pattern to the inorganic hard mask by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the inorganic hard mask on which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film on which the pattern has been transferred as a mask.

[0041] Furthermore, the present invention provides a pattern formation method, which comprises forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a titanium oxide film, and a titanium nitride film on the organic film, forming an organic antireflective film on the inorganic hard mask, forming a resist upper layer film on the organic antireflective film using a photoresist composition to form a four-layer film structure, forming a circuit pattern on the resist upper layer film, transferring the pattern to the organic antireflective film and the inorganic hard mask by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the inorganic hard mask on which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film on which the pattern has been transferred as a mask.

[0042] The organic film-forming material of the present invention can be suitably used in various pattern forming methods, such as a three-layer resist process using a silicon-containing resist intermediate film or an inorganic hard mask, and a four-layer resist process using an organic anti-reflective film in addition to these. In the manufacturing process of a semiconductor device, if a circuit pattern is formed by such a pattern forming method of the present invention, the semiconductor device can be manufactured with a high yield.

[0043] The inorganic hard mask is preferably formed by a CVD method or an ALD method.

[0044] In the pattern formation method of the present invention, for example, an inorganic hard mask can be formed by such a method.

[0045] In forming the circuit pattern, it is preferable to form the circuit pattern by lithography using light having a wavelength of 10 nm or more and 300 nm or less, direct drawing with an electron beam, nanoimprinting, or a combination of these.

[0046] In forming the circuit pattern, it is preferable to develop the circuit pattern using an alkali developer or an organic solvent.

[0047] In the pattern forming method of the present invention, such a circuit pattern forming means and developing means can be suitably used.

[0048] In addition, it is preferable to use, as the workpiece, a semiconductor device substrate, or a semiconductor device substrate having 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 formed thereon.

[0049] In addition, it is preferable to use, as the workpiece, one containing silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, cobalt, manganese, molybdenum, or an alloy thereof.

[0050] According to the pattern forming method of the present invention, a pattern can be formed by processing the above-mentioned workpiece. Effect of the Invention

[0051] As described above, the organic film forming material of the present invention can form a cured film without generating by-products even in film formation in an inert gas that prevents corrosion of the substrate, and is useful for forming an organic underlayer film having both high embedding and planarization properties. In addition, the organic film forming material of the present invention is a material that forms an organic film having excellent embedding / planarization properties and various properties such as heat resistance, etching resistance, and adhesion. Therefore, it is extremely useful as an organic film material in a multilayer resist method such as a two-layer resist method, a three-layer resist method using a silicon-containing intermediate film, and a four-layer resist method using a silicon-containing intermediate film and an organic anti-reflective film, or as a planarization material for manufacturing a semiconductor device. In addition, the organic film formed from the organic film forming material of the present invention has excellent heat resistance, so that even when a CVD hard mask is formed on the organic underlayer film, there is no film thickness variation due to thermal decomposition, and it is suitable for pattern formation. [Brief description of the drawings]

[0052] [Figure 1] FIG. 4 is an explanatory diagram of flattening characteristics in the present invention. [Diagram 2] FIG. 2 is an explanatory diagram of an example of a pattern forming method using a three-layer resist method according to the present invention. [Diagram 3] FIG. 2 is an explanatory diagram of a method for evaluating embedding characteristics in an embodiment. [Figure 4] FIG. 4 is an explanatory diagram of a method for evaluating flattening characteristics in an embodiment. [Diagram 5] FIG. 2 is an explanatory diagram showing a method for measuring adhesion in the examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0053] As described above, there has been a demand for the development of an organic film-forming material that can form an organic underlayer film that does not generate by-products even under film-forming conditions in an inert gas, for example at 300°C or higher, in order to prevent corrosion of the substrate, and that not only has excellent pattern filling and planarization properties when formed on a substrate, but also has good dry etching resistance during substrate processing, and that does not cause variation in the film thickness of the organic underlayer film due to thermal decomposition, even when a CVD hard mask is formed on the organic underlayer film.

[0054] Usually, when forming an organic underlayer film, a compound for forming an organic film is dissolved in an organic solvent to form a composition, which is applied to a substrate on which the structure and wiring of a semiconductor device are formed, and baked to form an organic underlayer film. Immediately after application of the composition, a coating film is formed that conforms to the shape of the step structure on the substrate, but when the coating film is baked, most of the organic solvent evaporates before it hardens, and an organic film is formed by the compound for forming an organic film remaining on the substrate. The present inventors have conceived that if the compound for forming an organic film remaining on the substrate at this time has sufficient thermal fluidity, it is possible to flatten the step shape immediately after application by thermal fluidity and form a flat film.

[0055] The present inventors have further conducted intensive research and have discovered that a polyimide having a polyimide structure represented by the above general formula (1A) as a main skeleton and R 1 It has been found that the polymer having a group having a triple bond represented by the following formula (1) introduced as a thermosetting group at the end as an organic film-forming material has thermosetting properties equivalent to those of conventional underlayer film materials not only in air but also in an inert gas, and has excellent thermal fluidity and therefore has high embedding / flattening properties. Furthermore, it has been found that the polymer can provide an organic film-forming material having high heat resistance and good adhesion to a substrate without variation in coating thickness due to thermal decomposition even when forming a CVD hard mask, and thus the present invention has been completed.

[0056] That is, the present invention is a material for forming an organic film, which contains (A) a polymer having a repeating unit represented by the above general formula (1A) and an end group which is a group represented by either of the above general formulas (1B) and (1C), and (B) an organic solvent.

[0057] The present invention will be described in detail below, but the present invention is not limited thereto.

[0058] <(A) Polymer> The polymer for forming an organic film used in the organic film-forming material of the present invention is a polymer having a repeating unit represented by the following general formula (1A) and an end group represented by either of the following general formulas (1B) and (1C). [ka] (In the formula, W 1 is a tetravalent organic group, and W 2 is a divalent organic group. [ka] [ka] (In the formula, R 1 is any one of the groups represented by the following formula (1D), and two or more R 1 may be used in combination.) [ka]

[0059] By forming a polyimide structure in advance that has been ring-closed as in (1A), (1B), and (1C) above, the by-product elimination reaction such as dehydration that occurs when polyimide compound precursors such as polyamic acid undergo thermal ring-closure is eliminated, film shrink is suppressed, and the flatness of the organic film is not impaired. In addition, by forming a stable imide structure in advance, decomposition due to equilibrium reactions of polyimide compound precursors such as polyamic acid can be suppressed, and storage stability is also superior. In addition, the polyimide structure contributes to improving adhesion to the substrate as well as imparting heat resistance. The improved adhesion prevents film peeling when forming an inorganic hard mask directly on an organic film using a CVD method or ALD method, making it possible to form an organic film with excellent process tolerance.

[0060] R represented by the above formula (1D) 1 functions as a thermal crosslinking group. In view of curability, heat resistance, and ease of availability of raw materials, an ethynyl group or an ethynylphenyl group is preferred.

[0061] W in the above general formula 1 Examples of the substituent include the following structural formulas, which may have a substituent on the aromatic ring. Examples of the substituent include a hydroxyl group, a trifluoromethyl group, an alkyl group having 1 to 10 carbon atoms, an alkynyl group or alkenyl group having 3 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkynyloxy group or alkenyloxy group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a nitro group, a halogen group, a nitrile group, an alkoxycarbonyl group having 1 to 10 carbon atoms, and an alkanoyloxy group having 1 to 10 carbon atoms.

[0062] [ka]

[0063] [ka]

[0064] [ka]

[0065] [ka]

[0066] [ka]

[0067] [ka]

[0068] W in the above general formula 2 Examples of the substituent include the following structural formulas, which may have a substituent on the aromatic ring. Examples of the substituent include a hydroxyl group, a trifluoromethyl group, an alkyl group having 1 to 10 carbon atoms, an alkynyl group or alkenyl group having 3 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkynyloxy group or alkenyloxy group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a thiol group, a nitro group, a halogen group, a nitrile group, a sulfonic acid group, an alkoxycarbonyl group having 1 to 10 carbon atoms, and an alkanoyloxy group having 1 to 10 carbon atoms.

[0069] [ka]

[0070] [ka]

[0071] [ka]

[0072] [ka]

[0073] Furthermore, the polymer used in the organic film-forming material of the present invention is W 1 is preferably a group represented by the following general formula (1E). [ka] (In the formula, W 3 is a single bond or a divalent organic group, which may have a substituent on the benzene ring in the formula, and W 3 The organic groups in may be bonded to form a cyclic organic group.

[0074] W represented by the above general formula (1E) 3 Preferred examples of the partial structure containing the formula include the following formulas. [ka]

[0075] [ka]

[0076] Furthermore, the polymer used in the organic film-forming material of the present invention is W 1 is preferably any one of the groups represented by the following formula (1F): Among these, from the viewpoints of solvent solubility and fluidity, those having one or more hexafluoroisopropylidene groups, ether bonds, fluorene structures, and indane structures are preferred. [ka] (The aromatic ring in the above formula may have a substituent.)

[0077] Among the above, a structure having a hexafluoroisopropylidene group as a linking group of the main chain, a structure having an ether bond, and a structure having a fluorene structure are particularly preferred. The ether bond functions as a flexible linking group, and can impart thermal fluidity and solvent solubility. Similarly, the hexafluoroisopropylidene group and the fluorene structure can obtain the same effect as the ether bond, since the aggregation of imide groups is suppressed by introducing flexibility into the main chain. This allows both high-level filling / flattening properties and heat resistance to be achieved.

[0078] Furthermore, the polymer used in the organic film-forming material of the present invention is W 2 is preferably a group represented by the following general formula (1G). [ka] (In the formula, W 4 is a single bond or a divalent organic group, which may have a substituent on the benzene ring in the formula, and W 4 The organic groups in may be bonded to form a cyclic organic group.

[0079] W represented by the above general formula (1G) 4 Preferred examples of the partial structure containing the formula include the following formulas. [ka]

[0080] Furthermore, the polymer used in the organic film-forming material of the present invention is W 2 is preferably any one of groups represented by the following formula (1H). [ka] (The aromatic ring in the above formula may have a substituent.)

[0081] Among the above, structures having an ether bond as a linking group of the main chain, a fluorene structure, an indane structure, and a structure having a hexafluoroisopropylidene group are particularly preferred. The ether bond functions as a flexible linking group, making it possible to impart thermal fluidity and solvent solubility. Similarly, structures having an indane structure, a fluorene structure, and a hexafluoroisopropylidene group introduce flexibility into the main chain, suppressing aggregation between imide groups, and can obtain the same effect as an ether bond. This allows for both high-level filling / flattening properties and heat resistance.

[0082] Furthermore, the polymer used in the organic film-forming material of the present invention is a polymer represented by the general formula (1A) 1 is one or more of the groups represented by formula (1F), and W in general formula (1A) 2 is preferably one or more of the groups represented by formula (1H).

[0083] W 1 and W 2 By using the above-mentioned combination of organic groups, it is possible to improve the thermal fluidity, heat resistance and adhesion.

[0084] Furthermore, the Mw (weight average molecular weight) of the above polymer is preferably 1,000 to 10,000, and more preferably 1,000 to 8,000.

[0085] Such a molecular weight ensures solubility in organic solvents and suppresses the generation of sublimates during baking. In addition, the polymer (polymer for forming organic film) of component (A) has good thermal fluidity, so that when it is mixed into a material for forming an organic film, it is possible to form an organic film that not only satisfactorily embeds the fine structure formed on the substrate, but also makes the entire substrate flat.

[0086] [(A) Method for Producing Polymer] As a method for obtaining a polymer used in the organic film material of the present invention, either one of the diamines and tetracarboxylic anhydrides shown below is charged in excess to obtain a polyamic acid intermediate (STEP 1) having an amino group or a carboxylic anhydride active end at the terminal. Then, R 1 After synthesizing a polyimide precursor (STEP 2) using a phthalic anhydride derivative or aniline derivative having as a substituent, the polymer of component (A) can be synthesized by further carrying out thermal or chemical imidization (STEP 3). The diamine compound or tetracarboxylic acid anhydride used in synthesizing the polyamic acid compound in STEP 1, and the phthalic anhydride derivative or aniline derivative used for end-capping in STEP 2 can be used alone or in combination of two or more kinds. These can be appropriately selected and combined depending on the required properties. W in the following formula 1 , W 2 , R 1 is the same as above.

[0087] (Diamine excess conditions) [ka] [ka] [ka]

[0088] (Tetracarboxylic acid excess condition) [ka] [ka] [ka]

[0089] The synthesis of the polyamic acid intermediate shown in STEP 1 can usually be carried out in an organic solvent at room temperature or under cooling or heating as necessary. Examples of the solvent that can be used include alcohols such as methanol, ethanol, isopropyl alcohol, butanol, ethylene glycol, propylene glycol, diethylene glycol, glycerol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether, ethers such as diethyl ether, dibutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, and 1,4-dioxane, chlorine-based solvents such as methylene chloride, chloroform, dichloroethane, and trichloroethylene, and hexafluorophenyl ether. Examples of the solvent include hydrocarbons such as benzene, heptane, benzene, toluene, xylene, cumene, etc.; nitriles such as acetonitrile, etc.; ketones such as acetone, ethyl methyl ketone, isobutyl methyl ketone, cyclohexanone, etc.; esters such as methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol methyl ether acetate, γ-butyrolactone, etc.; and aprotic polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, dimethylsulfoxide, N,N-dimethylformamide, hexamethylphosphoric triamide, etc., and these can be used alone or in combination of two or more kinds.

[0090] In these syntheses, a base catalyst can be used as necessary. Examples of the base catalyst include inorganic base compounds such as sodium hydrogen carbonate, sodium carbonate, potassium carbonate, calcium carbonate, cesium carbonate, sodium hydroxide, potassium hydroxide, sodium hydride, and potassium phosphate; and organic bases such as triethylamine, diisopropylethylamine, N,N-dimethylaniline, pyridine, and 4-dimethylaminopyridine. These may be used alone or in combination of two or more.

[0091] The reaction method includes a method of charging the diamine compound and the tetracarboxylic anhydride in a solvent all at once, a method of dropping the diamine compound and the tetracarboxylic anhydride dispersed or dissolved individually or mixed together, and a method of dropping one of the diamine compound and the tetracarboxylic anhydride dispersed or dissolved in a solvent and then dropping the other. In addition, when multiple types of diamine compounds and tetracarboxylic anhydrides are charged, they may be mixed and reacted in advance, or they can be reacted individually and sequentially. In the case of using a catalyst, the diamine compound or the tetracarboxylic anhydride are charged all at once, and the catalyst is dispersed or dissolved in advance and then dropped. It is possible to adjust the charging ratio of the diamine compound and the tetracarboxylic anhydride at any ratio so that the Mw range of the desired range is obtained. For example, when an aniline derivative is used as the terminal blocking agent in the next step, the tetracarboxylic anhydride is used in excess relative to the diamine compound, and when phthalic anhydride is used as the terminal blocking agent, the diamine compound is used in excess relative to the tetracarboxylic anhydride to synthesize a polyamide intermediate. The resulting reaction solution of the polyamic acid intermediate can be used to proceed to the end-capping reaction in STEP 2, but it can also be used to dilute the reaction intermediate in an organic solvent to remove unreacted raw materials, catalysts, and other components present in the system, and then recover the resulting product as a powder by separation washing or by crystallization with a poor solvent.

[0092] In the terminal blocking step in STEP 2, the reaction solution of the polyamic acid intermediate (if recovered as a powder, it is first dissolved) is reacted with a terminal blocking agent. The reaction solvent and reaction catalyst can be the same as those for the polyamic acid intermediate in STEP 1. In addition, the reaction method can be the same as in STEP 1, except that the substrate is a polyamic acid intermediate and an aniline derivative or phthalic anhydride is used as the terminal blocking agent instead of a diamine compound and a tetracarboxylic acid anhydride. The reaction solution of the obtained polyimide precursor can be continued to the imidization reaction in STEP 3, but it can also be diluted with an organic solvent to remove unreacted raw materials, catalysts, etc. present in the system as a reaction intermediate, and then crystallized with a poor solvent and recovered as a powder.

[0093] The imidization step shown in STEP 3 can be carried out by thermal or chemical imidization. These methods can be appropriately selected depending on the thermal stability of the crosslinking group of the target imide compound and the reactivity of the introduced substituent with the reagent used in the chemical imidization.

[0094] When thermal imidization is performed, a solvent capable of forming an azeotropic mixture with water is added to the reaction liquid of the polyamic acid obtained in STEP 2 (if the polyamic acid is recovered as a powder, it is dissolved in a soluble solvent in advance), and the mixture is heated to 100°C to 250°C. The imidization is performed by a dehydration ring-closing reaction while removing the water that is produced.

[0095] Examples of the solvent that can form an azeotropic mixture with water include esters such as γ-butyrolactone, polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, dimethylsulfoxide, and N,N-dimethylformamide, and non-polar solvents such as benzene, toluene, xylene, and mesitylene. It is preferable to use these solvents alone or in combination and heat them to distill off the water generated by ring closure from the system while dehydrating the mixture.

[0096] When chemical imidization is performed, a base catalyst and an acid anhydride or the like as a dehydrating agent are added to the reaction solution of the polyimide precursor obtained in STEP 2 (if it is recovered as a powder, it is dissolved in a soluble solvent beforehand), and the mixture is heated to perform imidization.

[0097] Examples of base catalysts used in chemical imidization include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine, among which pyridine is preferred because it has a suitable basicity for promoting the reaction. Examples of dehydrating agents include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, trifluoroacetic anhydride, polyphosphoric acid, phosphorus pentoxide, phosphorus pentachloride, and thionyl chloride, with acetic anhydride being preferred from the viewpoint of purification after the reaction. In addition, the base catalyst and the dehydrating agent may each be used alone or in a mixture of two or more kinds, and the imidization rate of these can be appropriately controlled by adjusting the amount of catalyst, the amount of dehydrating agent, the reaction temperature, and the reaction time according to the required performance of the target compound.

[0098] The solvent used in this case is not particularly limited as long as it is a solvent inert to the above reaction, and examples thereof include ethers such as diethylene glycol diethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, 1,4-dioxane, etc.; chlorine-based solvents such as methylene chloride, chloroform, dichloroethane, trichloroethylene, etc.; hydrocarbons such as hexane, heptane, benzene, toluene, xylene, cumene, etc.; nitriles such as acetonitrile, etc.; ketones such as acetone, ethyl methyl ketone, isobutyl methyl ketone, cyclohexanone, etc.; esters such as methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol methyl ether acetate, γ-butyrolactone, etc.; and aprotic polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, dimethylsulfoxide, N,N-dimethylformamide, hexamethylphosphoric triamide, etc., which can be used alone or in combination.

[0099] After the reaction is completed, the product may be used as it is as a material for forming an organic film, but it may also be recovered by diluting with an organic solvent and then separating and washing to remove unreacted raw materials, catalysts, etc. present in the system.

[0100] The organic solvent used for the separation washing is not particularly limited as long as it can dissolve the compound and separate into two layers when mixed with water, but examples thereof include 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 ethylcyclopentyl methyl ether, chlorine-based solvents such as methylene chloride, chloroform, dichloroethane, and trichloroethylene, and mixtures thereof. The washing water used in this case is usually what is called deionized water or ultrapure water. The number of washings may be one or more times, but since washing ten or more times does not necessarily provide the effect of washing alone, it is preferably about 1 to 5 times.

[0101] In order to remove unreacted raw materials or acidic components from the system during separation washing, washing may be performed with a basic aqueous solution. Specific examples of the base include alkali metal hydroxides, alkali metal carbonates, alkaline earth metal hydroxides, alkaline earth metal carbonates, ammonia, and organic ammonium.

[0102] Furthermore, in order to remove unreacted raw materials, metal impurities, or basic components from the system during separation and washing, washing may be performed with an acidic aqueous solution. Specific examples of the acid include 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.

[0103] The above-mentioned separation washing with a basic aqueous solution and an acidic aqueous solution may be performed either alone or in combination. From the viewpoint of removing metal impurities, the separation washing is preferably performed in the order of a basic aqueous solution and an acidic aqueous solution.

[0104] After the above-mentioned separation washing with the basic aqueous solution or acidic aqueous solution, washing with neutral water may be performed successively. The number of washings may be one or more times, but is preferably about 1 to 5 times. As the neutral water, the above-mentioned deionized water or ultrapure water may be used. The number of washings may be one or more times, but if the number of washings is too few, the basic components and acidic components may not be removed. Even if washing is performed 10 times or more, the effect of washing alone may not be obtained, so it is preferably about 1 to 5 times.

[0105] Furthermore, the reaction product after the liquid separation operation can be recovered as a powder by concentrating the solvent to dryness or crystallizing it under reduced pressure or normal pressure, but it can also be left in a solution state of a moderate concentration in order to improve operability when preparing an organic film-forming material. The concentration at this time is preferably 0.1 to 50 mass%, more preferably 0.5 to 30 mass%. At such a concentration, the viscosity is unlikely to increase, so that the operability is prevented from being impaired, and the amount of solvent is not excessive, so that it is economical.

[0106] The solvent used in this case is not particularly limited as long as it can dissolve the reaction product (polymer of component (A)). Specific examples include ketones such as cyclohexanone and methyl-2-amyl 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; and 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 can be used alone or in combination of two or more.

[0107] In the synthesis of the above polyimide, it is possible to combine diamine compounds constituting the main chain of the polymer, tetracarboxylic anhydride derivatives, phthalic acid derivatives used for terminal blocking, and aniline derivatives according to the required performance. Specifically, it is possible to introduce substituents that contribute to improving solvent solubility, adhesion, and filling / planarization properties, and substituents that contribute to etching resistance and film-forming properties according to the desired required performance. Organic film-forming materials using these polymers are capable of achieving both filling / planarization properties and heat resistance at a high level.

[0108] As described above, the polymer of component (A) provides a material for forming an organic film that has both heat resistance of 400° C. or more and high-level filling / planarizing properties.

[0109] In the present invention, the planarization property means the ability to planarize the surface of a substrate. For example, as shown in FIG. 1, the organic film forming material of the present invention can reduce a 100 nm step in the substrate 1 to 30 nm or less by applying the organic film forming material 3' onto the substrate 1 and heating it to form an organic film 3. The step shape shown in FIG. 1 shows a typical example of the step shape in a substrate for manufacturing a semiconductor device, and the step shape of a substrate that can be planarized by the organic film forming material of the present invention is not limited to this.

[0110] <Materials for organic film formation> The present invention provides a material for forming an organic film, the material containing (A) the above-mentioned polymer and (B) an organic solvent. In the material for forming an organic film of the present invention, the above-mentioned (A) polymer may be used alone or in combination of two or more.

[0111] The organic solvent usable in the organic film-forming material of the present invention is not particularly limited as long as it dissolves the components contained in the above-mentioned base polymer, and the materials such as the acid generator, crosslinking agent, and other additives described below. Specifically, a solvent having a boiling point of less than 180° C., such as the solvents described in paragraphs (0091) to (0092) of JP-A-2007-199653, can be used. Among them, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, 2-heptanone, cyclopentanone, cyclohexanone, and a mixture of two or more of these are preferably used.

[0112] Such an organic film-forming material can be applied by spin coating, and since it contains the above-mentioned polymer (A), it is an organic film-forming material that has both heat resistance of 400°C or more and high-level filling / planarizing properties.

[0113] Furthermore, in the organic film-forming material of the present invention, it is possible to add a high-boiling point solvent having a boiling point of 180° C. or more to the above-mentioned solvent having a boiling point of less than 180° C. (a mixture of a solvent having a boiling point of less than 180° C. and a solvent having a boiling point of 180° C. or more). The high-boiling point organic solvent is not particularly limited as long as it can dissolve the (A) polymer, and may be any of hydrocarbons, alcohols, ketones, esters, ethers, chlorine-based solvents, etc., but specific examples include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-Hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin, n-nonyl acetate, ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol-n-butyl ether, triethylene glycol butyl methyl ether, triethylene Glycol diacetate, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butylene glycol diacetate, 1,Examples of the monomer include 6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, and dibutyl adipate, and these may be used alone or in combination.

[0114] The boiling point of the high boiling point solvent may be appropriately selected according to the temperature at which the organic film-forming material is heat-treated, and the boiling point of the high boiling point solvent to be added is preferably 180°C to 300°C, and more preferably 200°C to 300°C. If the boiling point is too low, there is no risk of the solvent volatilizing too quickly during baking (heat treatment), and sufficient thermal fluidity can be obtained. In addition, if the boiling point is high, there is no risk of the solvent remaining in the film after baking without volatilizing, and there is no risk of adversely affecting the film properties such as etching resistance.

[0115] Furthermore, when the high boiling point solvent is used, the blending amount of the high boiling point solvent is preferably 1 to 30 parts by mass per 100 parts by mass of the solvent having a boiling point of less than 180° C. If the blending amount is such, there is no risk that the blending amount is too small to impart sufficient thermal fluidity during baking, or that the blending amount is too large to remain in the film, leading to deterioration of film properties such as etching resistance.

[0116] In the case of such an organic film-forming material, by imparting thermal fluidity to the above-mentioned (A) polymer by adding a high boiling point solvent, the organic film-forming material becomes one having both higher embedding and planarizing properties.

[0117] In the organic film-forming material of the present invention, an acid generator (C) can be added to further promote the curing reaction. The acid generator may be one that generates an acid by thermal decomposition or one that generates an acid by light irradiation, and any of these may be added. Specifically, the materials described in paragraphs (0061) to (0085) of JP-A-2007-199653 may be added, but are not limited thereto.

[0118] The acid generators may be used alone or in combination of two or more. When an acid generator is added, the amount of the acid generator added is preferably 0.05 to 50 parts, more preferably 0.1 to 10 parts, based on 100 parts of the polymer (A).

[0119] To improve the coating property in spin coating, a surfactant (D) can be added to the organic film-forming material of the present invention. As the surfactant, for example, those described in (0142) to (0147) of JP-A-2009-269953 can be used.

[0120] In addition, a crosslinking agent (E) may be added to the organic film-forming material of the present invention in order to enhance the curing property and further suppress intermixing with the upper layer film. The crosslinking agent is not particularly limited, and various known crosslinking agents can be widely used. Examples include melamine-based crosslinking agents, glycoluril-based crosslinking agents, benzoguanamine-based crosslinking agents, urea-based crosslinking agents, β-hydroxyalkylamide-based crosslinking agents, isocyanurate-based crosslinking agents, aziridine-based crosslinking agents, oxazoline-based crosslinking agents, and epoxy-based crosslinking agents.

[0121] Specific examples of the melamine-based crosslinking agent include hexamethoxymethylated melamine, hexabutoxymethylated melamine, alkoxy and / or hydroxyl-substituted derivatives thereof, and partial self-condensates thereof. Specific examples of the glycoluril-based crosslinking agent include tetramethoxymethylated glycoluril, tetrabutoxymethylated glycoluril, alkoxy and / or hydroxyl-substituted derivatives thereof, and partial self-condensates thereof. Specific examples of the benzoguanamine-based crosslinking agent include tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, alkoxy and / or hydroxyl-substituted derivatives thereof, and partial self-condensates thereof. Specific examples of the urea-based crosslinking agent include dimethoxymethylated dimethoxyethyleneurea, alkoxy and / or hydroxyl-substituted derivatives thereof, and partial self-condensates thereof. Specific examples of the β-hydroxyalkylamide-based crosslinking agent include N,N,N',N'-tetra(2-hydroxyethyl)adipic acid amide. Specific examples of the isocyanurate crosslinking agent include triglycidyl isocyanurate and triallyl isocyanurate.Specific examples of the aziridine crosslinking agent include 4,4'-bis(ethyleneiminocarbonylamino)diphenylmethane and 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl)propionate]. Specific examples of the oxazoline-based crosslinking agent include 2,2'-isopropylidenebis(4-benzyl-2-oxazoline), 2,2'-isopropylidenebis(4-phenyl-2-oxazoline), 2,2'-methylenebis4,5-diphenyl-2-oxazoline, 2,2'-methylenebis-4-phenyl-2-oxazoline, 2,2'-methylenebis-4-tertbutyl-2-oxazoline, 2,2'-bis(2-oxazoline), 1,3-phenylenebis(2-oxazoline), 1,4-phenylenebis(2-oxazoline), and 2-isopropenyloxazoline copolymer.Specific examples of epoxy crosslinking agents include diglycidyl ether, ethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, poly(glycidyl methacrylate), trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, and pentaerythritol tetraglycidyl ether.

[0122] In addition, in order to further improve the planarization / filling properties, a plasticizer (F) can be added to the organic film-forming material of the present invention. The plasticizer is not particularly limited, and various known plasticizers can be widely used. Examples include low molecular weight compounds such as phthalates, adipic esters, phosphates, trimellitates, and citrates, polyethers, polyesters, and polyacetal polymers described in JP-A-2013-253227.

[0123] In addition, in the organic film-forming material of the present invention, as an additive for imparting filling / flattening properties in the same manner as a plasticizer, for example, a liquid additive having a polyethylene glycol or polypropylene glycol structure, or a thermally decomposable polymer having a weight loss rate of 40% or more from 30° C. to 250° C. and a weight average molecular weight of 300 to 200,000 is preferably used. This thermally decomposable polymer preferably contains a repeating unit having an acetal structure represented by the following general formula (DP1) or (DP1a).

[0124] [ka] (In the formula, R 6 Y is a hydrogen atom or an optionally substituted saturated or unsaturated monovalent organic group having 1 to 30 carbon atoms. 1 is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.

[0125] [ka] (In the formula, R 6a is an alkyl group having 1 to 4 carbon atoms. a is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms, which may have an ether bond; and n represents the average number of repeating units and is 3 to 500.

[0126] As described above, the organic film-forming material of the present invention is a material for forming an organic film having both heat resistance of 400 ° C. or more and high embedding / flattening properties. Therefore, the organic film-forming material of the present invention is extremely useful as a material for forming an organic film in a multilayer resist method such as a two-layer resist method, a three-layer resist method using a silicon-containing resist intermediate film or a silicon-containing inorganic hard mask, and a four-layer resist method using a silicon-containing resist intermediate film or a silicon-containing inorganic hard mask and an organic anti-reflective film. In addition, the organic film-forming material of the present invention does not generate by-products even when formed in an inert gas, and has excellent embedding / flattening properties, so it can be suitably used as a flattening material in semiconductor device manufacturing processes other than the multilayer resist method.

[0127] <Substrates for manufacturing semiconductor devices> The present invention also provides a substrate for manufacturing a semiconductor device, which comprises a substrate on which an organic film is formed by curing the above-mentioned organic film-forming material.

[0128] If the organic film is formed from the organic film-forming material of the present invention, it will have high filling / planarization properties, and will be an organic film that is free of microvoids due to insufficient filling or unevenness on the organic film surface due to insufficient flatness. A substrate for manufacturing a semiconductor device that is planarized with such an organic film will have a wide process margin during patterning, making it possible to manufacture semiconductor devices with a high yield.

[0129] <Organic film formation method> The heating film formation process for forming an organic underlayer film can be performed by one-stage baking, two-stage baking, or multi-stage baking of three or more stages, but one-stage baking or two-stage baking is economically preferable. Film formation by one-stage baking is performed, for example, at a temperature of 100°C to 600°C in the range of 5 to 3600 seconds, but preferably at a temperature of 150°C to 500°C in the range of 10 to 7200 seconds. By performing heat treatment under such conditions, flattening due to thermal flow and crosslinking reaction can be promoted. In the multilayer resist method, a coating type silicon intermediate film or a CVD hard mask may be formed on the obtained film. When a coating type silicon intermediate film is applied, it is preferable to form the film at a temperature higher than the temperature at which the silicon intermediate film is formed. Usually, the silicon intermediate film is formed at a temperature of 100°C to 400°C, preferably 150°C to 350°C. Forming the organic underlayer film at a temperature higher than this temperature prevents dissolution of the organic underlayer film by the composition for forming a silicon intermediate film, and makes it possible to form an organic film that does not mix with the composition.

[0130] When a CVD hard mask is used, it is preferable to form the organic underlayer film at a temperature higher than the temperature at which the CVD hard mask is formed. The temperature at which the CVD hard mask is formed can be, for example, 150° C. or higher and 500° C. or lower.

[0131] On the other hand, in the case of film formation by two-stage baking, in the first stage, considering the influence of corrosion of the substrate by oxygen in the air, the upper limit of the treatment temperature in air is, for example, 300 ° C or less, preferably 250 ° C or less, in the range of 10 to 600 seconds. The second stage bake temperature is higher than the first stage bake temperature, and is preferably 600 ° C or less, preferably 500 ° C or less, and is preferably performed in the range of 10 to 7200 seconds. In the multilayer resist method, a coating type silicon intermediate film or a CVD hard mask may be formed on the obtained film. When a coating type silicon intermediate film is applied, it is preferable to form the film at a temperature higher than the temperature at which the silicon intermediate film is formed. Usually, the silicon intermediate film is formed at 100 ° C or more and 400 ° C or less, preferably 150 ° C or more and 350 ° C or less. When the organic underlayer film is formed at a temperature higher than this temperature, dissolution of the organic underlayer film by the composition for forming the silicon intermediate film can be prevented, and an organic film that does not mix with the composition can be formed.

[0132] When a CVD hard mask is applied in two-stage baking, it is preferable to form the organic underlayer film at a temperature higher than the temperature at which the CVD hard mask is formed. Examples of the temperature at which the CVD hard mask is formed include a temperature of 150° C. or higher and 500° C. or lower.

[0133] The present invention also provides a method for forming an organic film that functions as an organic underlayer film used in the manufacturing process of a semiconductor device, in which a hardened film is formed by heat-treating a workpiece substrate in an atmosphere with an oxygen concentration of 1% or less to prevent corrosion of the workpiece substrate.

[0134] In this organic film forming method, for example, the organic film forming material of the present invention is first spin-coated on a substrate to be processed. After spin-coating, in a two-stage bake, the material is first baked in air at 300° C. or less, and then the second stage baked in an atmosphere with an oxygen concentration of 1% or less. In the case of a one-stage bake, the first stage bake in air may be skipped. In addition, examples of the atmosphere during baking include inert gases such as nitrogen, argon, and helium. With the organic film forming material of the present invention, even if it is baked in such an inert gas atmosphere, a sufficiently hardened organic film can be formed without generating sublimates.

[0135] In addition, the organic film forming method of the present invention can use a substrate to be processed having a structure or step having a height of 30 nm or more. As described above, the organic film forming material of the present invention has excellent filling / flattening properties, so that even if the substrate to be processed has a structure or step (unevenness) having a height of 30 nm or more, a flat cured film can be formed. In other words, the organic film forming method of the present invention is particularly useful when forming a flat organic film on such a substrate to be processed.

[0136] The thickness of the organic film to be formed may be appropriately selected, but is preferably 30 to 20,000 nm, and more preferably 50 to 15,000 nm.

[0137] The above-mentioned method for forming an organic film can be applied to both the case where an organic film for an organic underlayer film is formed using the organic film-forming material of the present invention, and the case where an organic film for a planarizing film is formed.

[0138] The present invention provides a method for forming an organic film that is applied in the manufacturing process of a semiconductor device, which comprises spin-coating the above-mentioned organic film-forming material onto a substrate to be processed, and then heat-treating the substrate to which the organic film-forming material has been applied in an inert gas atmosphere at a temperature of 50°C or higher and 600°C or lower for a period of 10 to 7200 seconds to obtain a cured film.

[0139] The present invention further provides a method for forming an organic film to be applied in a manufacturing process of a semiconductor device, which comprises spin-coating the above-mentioned organic film-forming material onto a substrate to be processed, heat-treating the substrate to which the organic film-forming material has been applied in air at a temperature of 50°C or higher and 250°C or lower for 5 to 600 seconds, preferably 10 to 600 seconds, to form a coating film, and subsequently heat-treating the substrate in an inert gas atmosphere at a temperature of 200°C or higher and 600°C or lower, preferably 250°C or higher, for 10 to 7200 seconds to obtain a cured film.

[0140] The organic film formed by the method of the present invention and applied in the manufacturing process of a semiconductor device has high heat resistance and advanced filling / planarization properties, and when used in the manufacturing process of a semiconductor device, the yield of the semiconductor device is improved.

[0141] In this organic film forming method, first, the organic film forming material of the present invention described above is spin-coated (spin-coated) onto a substrate to be processed. By using the spin-coating method, good embedding properties can be obtained. After spin-coating, baking (heat treatment) is performed to promote flattening by thermal flow and cross-linking reaction. This baking can evaporate the solvent in the organic film forming material, so mixing can be prevented even when a resist top layer film or a silicon-containing resist intermediate film is formed on the organic film.

[0142] <Pattern formation method> [Three-layer resist method using silicon-containing resist intermediate film] The present invention also provides a pattern forming method, which includes forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming a silicon-containing resist intermediate film on the organic film using a silicon-containing resist intermediate film material, forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist composition, forming a circuit pattern on the resist upper layer film, transferring the pattern to the silicon-containing resist intermediate film by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film to which the pattern has been transferred as a mask.

[0143] As the workpiece, it is preferable to use a semiconductor device substrate, or a semiconductor device substrate having 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 formed thereon. More specifically, although not limited thereto, examples thereof include Si, α-Si, p-Si, SiO 2 Substrates made of materials such as SiN, SiON, W, TiN, and Al, and substrates on which the above-mentioned metal films are formed as layers to be processed, are used.

[0144] The processed layer is Si, SiO 2 Various low-k films and their stopper films such as SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, and Al-Si are used, and can be formed to a thickness of usually 50 to 10,000 nm, particularly 100 to 5,000 nm. When forming a processed layer, the substrate and the processed layer are made of different materials.

[0145] The metal constituting the workpiece is preferably silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, cobalt, manganese, molybdenum, or an alloy thereof.

[0146] In addition, it is preferable to use a substrate having a structure or step having a height of 30 nm or more as the workpiece.

[0147] When forming an organic film on a workpiece using the organic film-forming material of the present invention, the above-mentioned organic film-forming method of the present invention may be applied.

[0148] Next, a resist intermediate film (silicon-containing resist intermediate film) is formed on the organic film using a resist intermediate film material containing silicon atoms. As the silicon-containing resist intermediate film material, a polysiloxane-based intermediate film material is preferable. By imparting an anti-reflection effect to the silicon-containing resist intermediate film, reflection can be suppressed. In particular, for 193 nm exposure, if a material containing many aromatic groups and having high etching selectivity with the substrate is used as the organic film forming material, the k value becomes high and the substrate reflection becomes high, but by imparting absorption to an appropriate k value as the silicon-containing resist intermediate film, it becomes possible to suppress reflection, and the substrate reflection can be reduced to 0.5% or less. As the silicon-containing resist intermediate film having an anti-reflection effect, anthracene is preferably used for 248 nm and 157 nm exposure, and polysiloxane having a phenyl group or a light-absorbing group having a silicon-silicon bond in a pendant structure or polysiloxane structure for 193 nm exposure, which is crosslinked by acid or heat.

[0149] Next, a resist upper layer film is formed on the silicon-containing resist intermediate film using a resist upper layer film material consisting of a photoresist composition. The resist upper layer film material may be either positive or negative, and the same as a commonly used photoresist composition can be used. After spin-coating the resist upper layer film material, it is preferable to perform pre-baking at 60 to 180°C for 10 to 300 seconds. Thereafter, exposure is performed according to a conventional method, and further post-exposure baking (PEB) and development are performed to obtain a resist upper layer film pattern. The thickness of the resist upper layer film is not particularly limited, but is preferably 30 to 500 nm, and particularly preferably 50 to 400 nm.

[0150] Next, a circuit pattern (resist upper layer film pattern) is formed on the resist upper layer film. In forming the circuit pattern, it is preferable to form the circuit pattern by lithography using light having a wavelength of 10 nm or more and 300 nm or less, direct drawing with an electron beam, nanoimprinting, or a combination of these.

[0151] The exposure light is a high-energy ray with a wavelength of 300 nm or less, specifically, far ultraviolet light, KrF excimer laser light (248 nm), ArF excimer laser light (193 nm), F 2 Laser light (157 nm), Kr 2 Laser light (146 nm), Ar 2 Examples of the light include laser light (126 nm), soft X-rays (EUV) of 3 to 20 nm, electron beams (EB), ion beams, and X-rays.

[0152] In forming the circuit pattern, it is preferable to develop the circuit pattern using an alkali developer or an organic solvent.

[0153] Next, the circuit pattern is formed on the resist upper layer film 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 layer film pattern as a mask is preferably performed using a fluorocarbon gas. Thus, a silicon-containing resist intermediate film pattern is formed.

[0154] Next, the pattern is transferred to the organic film by etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask. The silicon-containing resist intermediate film exhibits higher etching resistance to oxygen gas or hydrogen gas than organic matter, 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 gas or hydrogen gas. This allows the organic film pattern to be formed.

[0155] Next, the pattern is transferred to the workpiece by etching using the organic film with the transferred pattern as a mask. The next etching of the workpiece (workpiece layer) can be performed by a conventional method. For example, if the workpiece is SiO 2For SiN or silica-based low dielectric constant insulating films, etching is mainly done with fluorocarbon gases, while for p-Si, Al, or W, etching is mainly done with chlorine- or bromine-based gases. If the substrate is processed by etching with fluorocarbon gases, the silicon-containing resist intermediate film pattern is stripped at the same time as the substrate is processed. On the other hand, if the substrate is processed by etching with chlorine- or bromine-based gases, a separate dry etching stripping with fluorocarbon gases must be performed after substrate processing in order to strip the silicon-containing resist intermediate film pattern.

[0156] An organic film obtained by using the organic film-forming material of the present invention can have excellent etching resistance when etching the workpiece as described above.

[0157] [Four-layer resist method using silicon-containing resist intermediate film and organic anti-reflective film] Furthermore, the present invention provides a pattern forming method, which comprises forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming a silicon-containing resist intermediate film on the organic film using a silicon-containing resist intermediate film material, forming an organic antireflective film on the silicon-containing resist intermediate film, forming a resist upper layer film on the organic antireflective film using a photoresist composition to form a four-layer film structure, forming a circuit pattern on the resist upper layer film, transferring the pattern to the organic antireflective film and the silicon-containing resist intermediate film by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film to which the pattern has been transferred as a mask.

[0158] This method can be carried out in the same manner as the three-layer resist method using the silicon-containing resist intermediate film described above, except that an organic antireflective coating (BARC) is formed between the silicon-containing resist intermediate film and the resist top layer film.

[0159] The organic anti-reflection film can be formed by spin coating using a known organic anti-reflection film material.

[0160] [Three-layer resist method using inorganic hard mask] Furthermore, the present invention provides a pattern formation method, which comprises forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a titanium oxide film, and a titanium nitride film on the organic film, forming a resist upper layer film on the inorganic hard mask using a photoresist composition, forming a circuit pattern on the resist upper layer film, transferring the pattern to the inorganic hard mask by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the inorganic hard mask on which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film on which the pattern has been transferred as a mask.

[0161] This method can be carried out in the same manner as the three-layer resist method using the silicon-containing resist intermediate film described above, except that an inorganic hard mask is formed on the organic film instead of the silicon-containing resist intermediate film.

[0162] The inorganic hard mask selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film (SiON film) can be formed by CVD method, ALD method, etc. Methods for forming silicon nitride film are described in, for example, JP 2002-334869 A and WO 2004 / 066377 A. The thickness of the inorganic hard mask is preferably 5 to 200 nm, more preferably 10 to 100 nm. As the inorganic hard mask, a SiON film having a high effect as an anti-reflection film is most preferably used. Since the substrate temperature when forming the SiON film is 300 to 500°C, the underlayer film needs to withstand a temperature of 300 to 500°C. The organic film formed using the organic film forming material of the present invention has high heat resistance and can withstand high temperatures of 300 to 500°C, so that it is possible to combine an inorganic hard mask formed by CVD method or ALD method with an organic film formed by spin coating method.

[0163] [Four-layer resist method using inorganic hard mask and organic anti-reflective coating] Furthermore, the present invention provides a pattern formation method, which comprises forming an organic film on a workpiece using the above-mentioned organic film-forming material, forming an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a titanium oxide film, and a titanium nitride film on the organic film, forming an organic antireflective film on the inorganic hard mask, forming a resist upper layer film on the organic antireflective film using a photoresist composition to form a four-layer film structure, forming a circuit pattern on the resist upper layer film, transferring the pattern to the organic antireflective film and the inorganic hard mask by etching using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the organic film by etching using the inorganic hard mask on which the pattern has been transferred as a mask, and further transferring the pattern to the workpiece by etching using the organic film on which the pattern has been transferred as a mask.

[0164] This method can be carried out in the same manner as the above-mentioned three-layer resist method using an inorganic hard mask, except that an organic antireflective coating (BARC) is formed between the inorganic hard mask and the resist top layer.

[0165] In particular, when a SiON film is used as the inorganic hard mask, the two-layer anti-reflection coating of the SiON film and BARC makes it possible to suppress reflections even in immersion lithography with a high NA exceeding 1.0. Another advantage of forming a BARC is that it has the effect of reducing the tailing of the resist top layer pattern directly above the SiON film.

[0166] Here, an example of a pattern forming method by the three-layer resist method of the present invention is shown in Figures 2(A) to (F). In the case of the three-layer resist method, as shown in Figure 2(A), an organic film 3 is formed on a workpiece layer 2 formed on a substrate 1 using the organic film forming material of the present invention, and then a silicon-containing resist intermediate film 4 is formed thereon, and a resist upper layer film 5 is formed thereon. Then, as shown in Figure 2(B), an exposed portion 6 of the resist upper layer film 5 is exposed to light, and PEB (post exposure bake) is performed. Then, as shown in Figure 2(C), development is performed to form a resist upper layer film pattern 5a. Then, as shown in Figure 2(D), the silicon-containing resist intermediate film 4 is dry-etched using a fluorocarbon gas with the resist upper layer film pattern 5a as a mask, to form a silicon-containing resist intermediate film pattern 4a. Then, as shown in Figure 2(E), after removing the resist upper layer film pattern 5a, the organic film 3 is oxygen plasma etched with the silicon-containing resist intermediate film pattern 4a as a mask, to form an organic film pattern 3a. Furthermore, as shown in FIG. 2(F), after removing the silicon-containing resist intermediate film pattern 4a, the process layer 2 is etched using the organic film pattern 3a as a mask to form a pattern 2a.

[0167] When forming an inorganic hard mask, the silicon-containing resist intermediate film 4 may be changed to an inorganic hard mask, and when forming a BARC, the BARC may be formed between the silicon-containing resist intermediate film 4 and the resist upper layer film 5. Etching of the BARC may be performed consecutively prior to etching of the silicon-containing resist intermediate film 4, or etching of only the BARC may be performed, and then etching of the silicon-containing resist intermediate film 4 may be performed by changing the etching device, for example.

[0168] As described above, the pattern forming method of the present invention makes it possible to form a fine pattern on a workpiece with high precision by a multi-layer resist method. EXAMPLES

[0169] The present invention will be described in more detail below with reference to Synthesis Examples, Comparative Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited thereto. Note that, as for the molecular weight and dispersity, the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene were determined by gel permeation chromatography (GPC) using tetrahydrofuran as an eluent, and the dispersity (Mw / Mn) was determined.

[0170] Synthesis example: Synthesis of polymers for organic film forming materials The following tetracarboxylic acid anhydrides (B1) to (B6), diamine compounds (C1) to (C6), aniline derivatives as end-capping agents, and phthalic anhydride derivatives (D1) to (D5) were used to synthesize polymers (A1) to (A16) for organic film-forming materials. A 60:40 mixture of isomers was used for (C3).

[0171] Tetracarboxylic acid anhydrides: [ka]

[0172] Diamine compounds: [ka]

[0173] End-capping agent: [ka]

[0174] [Synthesis Example 1] Synthesis of polymer (A1) 15.55g of tetracarboxylic anhydride (B1) and 14.62g of diamine compound (C1) were added with 120g of NMP (N-methyl-2-pyrrolidone), and the reaction was carried out for 3 hours at an internal temperature of 40°C under a nitrogen atmosphere. 5.16g of terminal blocking agent (D1) was added to the obtained polyamic acid intermediate solution, and the reaction was carried out for another 3 hours at an internal temperature of 40°C to obtain a polyimide precursor solution. 4.00g of pyridine was added to the obtained reaction solution, and 12.25g of acetic anhydride was slowly dropped, and then the reaction was carried out for 4 hours at an internal temperature of 60°C to carry out imidization. After the reaction was completed, the mixture was cooled to room temperature, 400g of methyl isobutyl ketone was added, and the organic layer was washed twice with 100g of 3% aqueous nitric acid solution, and then washed six times with 100g of pure water, and the organic layer was dried under reduced pressure. 100g of THF (tetrahydrofuran) was added to the residue to make a homogeneous solution, and then crystallized with 400g of methanol. The precipitated crystals were separated by filtration, washed twice with 300 g of methanol, and collected. The collected crystals were dried in vacuum at 70° C. to obtain a polymer (A1). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (A1): Mw = 4320, Mw / Mn = 1.72

[0175] [Synthesis Examples 2 to 16] Synthesis of Polymers (A2) to (A16) Polymers (A2) to (A16) shown in Table 1 were obtained as products under the same reaction conditions as in Synthesis Example 1, except that the diamine compounds, tetracarboxylic anhydrides, and end-capping agents shown in Table 1 were used. The weight average molecular weights (Mw) and dispersity (Mw / Mn) of these polymers were determined and are shown in Table 2.

[0176] [Table 1]

[0177] The compounds (E1) to (E5) shown below, the above-mentioned tetracarboxylic acid anhydrides (B4) and (B5), the diamine compounds (C2) and (C3), and the end-capping agents (D3) and (D5) were used to synthesize the polymers (A17) and (A18) for organic film-forming materials and the comparative polymers (R1) to (R3). [ka]

[0178] [Synthesis Example 17] Synthesis of polymer (A17) 50g of THF was added to 6.32g of compound (E2), and a homogeneous solution was prepared in an ice bath under a nitrogen atmosphere. 4.00g of diamine compound (C3) and 3.34g of triethylamine, which had been dissolved in 20g of NMP in advance, were slowly added dropwise, and the reaction was carried out at room temperature for 1 hour. 14.28g of compound (E1) and 100g of NMP were further added to the reaction solution, and the reaction was carried out at an internal temperature of 40°C for 3 hours, after which 11.18g of end-capping agent (D3) was added to obtain a polyimide precursor. 150g of o-xylene was added to the resulting reaction solution, and the reaction was carried out for 9 hours while removing the low boiling point products and water produced at an internal temperature of 180°C from the system, to carry out imidization. After the reaction was completed, the solution was cooled to room temperature and crystallized in 600g of diisopropyl ether. The precipitated crystals were separated by filtration, washed twice with 200g of diisopropyl ether, and then collected. The collected crystals were dried in a vacuum at 70°C to obtain (A17). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (A17): Mw = 2930, Mw / Mn = 1.42

[0179] [Synthesis Example 18] Synthesis of polymer (A18) 100g of THF was added to 12.07g of compound (E2), and a homogeneous solution was prepared in an ice bath under a nitrogen atmosphere. 10.00g of diamine compound (C2) and 6.39g of triethylamine, which had been dissolved in 60g of NMP in advance, were slowly added dropwise, and the reaction was carried out at room temperature for 1 hour. 4.00g of diamine compound (C2) was further added to the reaction solution, and the reaction was carried out at an internal temperature of 40°C for 3 hours, after which 5.93g of end-capping agent (D5) was added to obtain a polyimide precursor. 2.27g of pyridine was added to the resulting reaction solution, and 7.04g of acetic anhydride was slowly added dropwise, and the reaction was carried out at an internal temperature of 60°C for 4 hours to carry out imidization. After the reaction was completed, 400g of methyl isobutyl ketone was added, and then 100g of 5% aqueous hydrochloric acid was slowly added while cooling in an ice bath to quench the reaction. After quenching, the aqueous layer was removed, and the organic layer was washed six times with 100 g of 3% aqueous nitric acid solution and 100 g of pure water, and then the organic layer was dried under reduced pressure. 100 g of THF was added to the residue to make a homogeneous solution, and then crystallized with 400 g of methanol. The precipitated crystals were separated by filtration, washed twice with 300 g of methanol, and collected. The collected crystals were dried in vacuum at 70°C to obtain (A18). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (A18): Mw = 2760, Mw / Mn = 1.37

[0180] [Synthesis Example 19] Synthesis of polymer (R1) 10.28g of tetracarboxylic anhydride (B5) and 13.94g of diamine compound (C2) were added with 120g of NMP (N-methyl-2-pyrrolidone), and the reaction was carried out for 3 hours at an internal temperature of 40°C under a nitrogen atmosphere. 7.11g of (E3) was added as an end-capping agent to the obtained polyamic acid intermediate solution, and the reaction was carried out for another 3 hours at an internal temperature of 40°C to obtain a polyimide precursor solution. 1.98g of pyridine was added to the obtained reaction solution, and 12.25g of acetic anhydride was slowly dropped, and then the reaction was carried out for 4 hours at an internal temperature of 60°C to carry out imidization. After the reaction was completed, the mixture was cooled to room temperature, 400g of methyl isobutyl ketone was added, and the organic layer was washed twice with 100g of 3% aqueous nitric acid solution, and then washed six times with 100g of pure water, and the organic layer was dried under reduced pressure. 100g of THF (tetrahydrofuran) was added to the residue to make a homogeneous solution, and then crystallized with 400g of methanol. The precipitated crystals were separated by filtration, washed twice with 300 g of methanol, and collected. The collected crystals were dried in vacuum at 70° C. to obtain polymer (R1). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (R1): Mw=2450, Mw / Mn=1.44

[0181] [Synthesis Example 20] Synthesis of polymer (R2) 19.28g of tetracarboxylic anhydride (B5) and 4.18g of diamine compound (C2) were added with 120g of NMP (N-methyl-2-pyrrolidone), and the reaction was carried out for 3 hours at an internal temperature of 40°C under a nitrogen atmosphere. 3.35g of (E4) was added as an end-capping agent to the obtained polyamic acid intermediate solution, and the reaction was carried out for another 3 hours at an internal temperature of 40°C to obtain a polyimide precursor solution. 1.98g of pyridine was added to the obtained reaction solution, and 12.25g of acetic anhydride was slowly dropped, and then the reaction was carried out for 4 hours at an internal temperature of 60°C to carry out imidization. After the reaction was completed, the mixture was cooled to room temperature, 400g of methyl isobutyl ketone was added, and the organic layer was washed twice with 100g of 3% aqueous nitric acid solution, and then further washed six times with 100g of pure water, and the organic layer was dried under reduced pressure. 100g of THF (tetrahydrofuran) was added to the residue to make a homogeneous solution, and then crystallized with 400g of methanol. The precipitated crystals were separated by filtration, washed twice with 300 g of methanol, and collected. The collected crystals were dried in vacuum at 70° C. to obtain polymer (R2). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (R2): Mw=2320, Mw / Mn=1.39

[0182] [Synthesis Example 21] Synthesis of polymer (R3) 10.41g of tetracarboxylic anhydride (B4) and 10.66g of diamine compound (C3) were added with 100g of NMP (N-methyl-2-pyrrolidone), and the reaction was carried out for 3 hours at an internal temperature of 40°C under a nitrogen atmosphere. 3.92g of (E5) was added as an end-capping agent to the obtained polyamic acid intermediate solution, and the reaction was carried out for another 3 hours at an internal temperature of 40°C to obtain a polyimide precursor solution. 3.28g of sodium acetate was added to the obtained reaction solution, and 9.81g of acetic anhydride was slowly added dropwise, and the reaction was carried out for 4 hours at an internal temperature of 60°C to carry out imidization. After the reaction was completed, the mixture was cooled to room temperature, 400g of methyl isobutyl ketone was added, and the organic layer was washed twice with 100g of 3% aqueous nitric acid solution, and then washed six times with 100g of pure water, and the organic layer was dried under reduced pressure. 100g of THF (tetrahydrofuran) was added to the residue to make a homogeneous solution, and then crystallized with 400g of diisopropyl ether. The precipitated crystals were separated by filtration, washed twice with 300 g of diisopropyl ether, and collected. The collected crystals were dried in vacuum at 70° C. to obtain polymer (R3). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (R3): Mw = 2370, Mw / Mn = 1.41

[0183] [Synthesis Example 22] Synthesis of compound (R4) 10.00g of 1,3-diethynylbenzene, 30.00g of 1,3-diiodobenzene, 0.6g of bis(triphenylphosphine)dichloropalladium and 0.4g of copper iodide (I) as catalysts, 40g of piperidine, and 200g of THF were added, and the reaction was carried out for 3 hours at an internal temperature of 30°C under a nitrogen atmosphere. After that, 3.57g of ethynylbenzene was added as an end-capping agent, and the reaction was carried out for another 3 hours at an internal temperature of 30°C. After the reaction was completed, the product was crystallized with 400g of methanol. The precipitated crystals were separated by filtration, washed twice with 200g of methanol, and then collected. The collected crystals were vacuum dried at 70°C to obtain polymer (R4). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: [ka] (R4): Mw = 2120, Mw / Mn = 1.81

[0184] The structural formulas, weight average molecular weights (Mw) and dispersity (Mw / Mn) of the polymers obtained above are shown in Table 2. The Mw and Mw / Mn of the polymers (R1) to (R4) used in the comparative examples are also shown in Table 2.

[0185] [Table 2-1]

[0186] [Table 2-2]

[0187] [Table 2-3]

[0188] [Table 2-4]

[0189] [Table 2-5]

[0190] Preparation of organic film-forming compositions (UDL-1 to 22, Comparative Examples UDL1 to 4) The polymers (A1) to (A18) and (R1) to (R4) and the high boiling point solvents (S1) 1,6-diacetoxyhexane: boiling point 260° C., (S2) γ-butyrolactone: boiling point 204° C., and (S3) tripropylene glycol monomethyl ether: boiling point 242° C. were used. Propylene glycol monomethyl ether acetate (PGMEA) containing 0.1 mass % of FC-4430 (manufactured by Sumitomo 3M Limited) and cyclohexanone (CyHO) were used to dissolve the components in the proportions shown in Table 3, and then filtered through a 0.1 μm fluororesin filter to prepare compositions for forming organic films (UDL-1 to 22, comparative UDL-1 to 4).

[0191] [Table 3]

[0192] Example 1 Solvent Resistance Measurement (Examples 1-1 to 1-22, Comparative Examples 1-1 to 1-4) The organic film-forming compositions (UDL-1 to 22, Comparative UDL-1 to 4) prepared above were applied onto silicon substrates, baked at 450°C for 60 seconds under a nitrogen flow with an oxygen concentration controlled to 0.2% or less, and the film thickness was measured. PGMEA solvent was dispensed onto the coating, left for 30 seconds, spin-dried, and baked at 100°C for 60 seconds to evaporate the PGMEA. The film thickness was then measured and the difference in film thickness before and after the PGMEA treatment was determined.

[0193] [Table 4]

[0194] As shown in Table 4, the organic film-forming materials of the present invention (Examples 1-1 to 1-22) had a residual film rate of 99% or more after PGMEA treatment, and it was found that a crosslinking reaction occurred even in a nitrogen atmosphere, and sufficient solvent resistance was exhibited. In contrast, in Comparative Examples 1-1 and 1-2, which used polyimide without a crosslinking group, the residual film rate after PGMEA treatment was about 70%, and sufficient solvent resistance was not exhibited. From these results, it can be seen that the R introduced as a substituent 1 It can be seen that the group functions effectively as a thermal crosslinking group.

[0195] Example 2 Evaluation of heat resistance characteristics (Examples 2-1 to 2-22, Comparative Examples 2-1 to 2-4) The above organic film-forming compositions (UDL-1 to 22, Comparative UDL-1 to 4) were each applied onto a silicon substrate and baked in air at 180°C for 60 seconds to form a 200 nm coating film, and the film thickness A was measured. This substrate was further baked for an additional 10 minutes at 450°C in a nitrogen stream with an oxygen concentration controlled to 0.2% or less, and the film thickness B was measured. These results are shown in Table 5.

[0196] [Table 5]

[0197] As shown in Table 5, the organic film-forming materials of the present invention (Examples 2-1 to 2-22) showed a film thickness reduction of less than 1% even after baking at 450°C, and the organic film-forming materials of the present invention maintained the film thickness before high-temperature baking even after baking at 450°C, demonstrating high heat resistance. In contrast, compared with Comparative Examples 2-1 and 2-2, which used polyimides without crosslinking groups, the organic film-forming materials of the present invention had a terminal crosslinking group R 1 It can be seen that a dense film is formed by thermal crosslinking with the bismaleimide structure, and a film having excellent heat resistance is formed. Also, in Comparative Example 2-3 having a bismaleimide structure as a crosslinking group, solvent resistance is exhibited by thermal crosslinking under the conditions of Example 1, but sufficient heat resistance is not exhibited by thermal crosslinking with the bismaleimide structure under the conditions of long-term high-temperature treatment as in Example 2.

[0198] Example 3: Evaluation of filling characteristics (Examples 3-1 to 3-22, Comparative Examples 3-1 to 3-4) As shown in FIG. 3, the organic film-forming compositions (UDL-1 to 22, Comparative UDL-1 to 4) were each applied to a SiO 2The solution was applied onto a wafer substrate and baked on a hot plate at 450° C. for 60 seconds under a nitrogen gas flow with an oxygen concentration controlled to 0.2% or less to form an organic film 8. The substrate used was a base substrate 7 (SiO 2 The cross-sectional shape of each of the obtained wafer substrates was observed using a scanning electron microscope (SEM) to confirm whether the holes were filled with the organic film without any voids (air gaps). The results are shown in Table 6. When an organic film material with poor filling properties was used, voids occurred inside the holes in this evaluation. When an organic film material with good filling properties was used, the organic film filled the holes without any voids, as shown in Figure 3 (I).

[0199] [Table 6]

[0200] As shown in Table 6, it was confirmed that the organic film-forming material of the present invention (Examples 3-1 to 3-22) can fill a hole pattern without generating voids and has good filling properties. On the other hand, it was confirmed that voids were generated and the filling properties were poor in Comparative Examples 3-1 to 3-3. From this result, it can be seen that the organic film-forming material of the present invention ensures heat resistance by the thermosetting reaction and improves the filling properties. On the other hand, Comparative Examples 3-1 to 3-3 did not have good filling properties because of insufficient heat resistance, even in Comparative Example UDL-3 in which solvent resistance was expressed. In Comparative Example 3-4, although solvent resistance and heat resistance in a nitrogen atmosphere were ensured, thermal fluidity was insufficient, resulting in insufficient filling.

[0201] Example 4: Evaluation of planarization characteristics (Examples 4-1 to 4-22, Comparative Examples 4-1 to 4-4) The organic film-forming compositions (UDL-1 to 22, Comparative UDL-1 to 4) were each applied to a base substrate 9 (SiO 2The organic film 10 was coated on a wafer (wafer substrate) and baked at 450°C for 60 seconds in a nitrogen stream with an oxygen concentration controlled to 0.2% or less. The step (delta10 in Fig. 4(K)) between the trench and non-trench portions was then observed using an atomic force microscope (AFM) NX10 manufactured by Park Systems. The results are shown in Table 7. In this evaluation, the smaller the step, the better the planarization characteristics. In this evaluation, a trench pattern with a depth of 0.10 µm was planarized using an organic film material with a normal thickness of about 0.2 µm, which creates strict evaluation conditions for evaluating the superiority or inferiority of the planarization characteristics.

[0202] [Table 7]

[0203] As shown in Table 7, the organic film forming material of the present invention (Examples 4-1 to 4-22) had a smaller step between the organic film in the trench portion and the non-trench portion than Comparative Examples 4-1 to 4-4, and was confirmed to have excellent flattening properties. In Comparative Example 4-3, as shown in the heat resistance evaluation result of Example 2, the heat resistance was poor, so the film thickness loss caused by high-temperature baking was large, and the film thickness difference between the upper and lower steps was emphasized, resulting in poor flatness, and the above-mentioned results were obtained. In Comparative Examples 4-1 and 4-2, similarly, a non-crosslinked polyimide was used, so the influence of film loss due to high-temperature treatment was large, resulting in poor flatness. In Comparative Example 4-4, the heat resistance was sufficient, so the film loss was suppressed, but as can be seen from the evaluation result of the filling property in Example 3, the thermal fluidity was poor, so the flatness was not good. In addition, when Examples 4-20 to 4-22 in which a high-boiling point solvent was added were compared with Examples 4-2, 4-7, and 4-15 in which a high-boiling point solvent was not added, it was found that the flatness was further improved by adding a high-boiling point solvent.

[0204] Example 5 Pattern formation test (Examples 5-1 to 5-22, Comparative Examples 5-1 to 5-4) The organic film-forming compositions (UDL-1 to 22, Comparative UDL-1 to 4) were each prepared by dissolving 300 nm SiO 2The coating was applied onto a silicon wafer substrate on which a film had been formed, and baked at 450°C for 60 seconds under a nitrogen flow with an oxygen concentration controlled to 0.2% or less to form an organic film (resist underlayer film) with a thickness of 200 nm. A CVD-SiON hard mask was formed on top of the coating, and an organic anti-reflective coating material (ARC-29A: manufactured by Nissan Chemical Co., Ltd.) was applied and baked at 210°C for 60 seconds to form an organic anti-reflective coating with a thickness of 80 nm. A single layer resist for ArF, which is a resist upper layer film material, was applied on top of the coating, and baked at 105°C for 60 seconds to form a photoresist film with a thickness of 100 nm. An immersion protective film material (TC-1) was applied onto the photoresist film and baked at 90°C for 60 seconds to form a protective film with a thickness of 50 nm.

[0205] The resist top layer film material (ArF single layer resist) was prepared by dissolving a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) in a solvent containing 0.1 mass% FC-430 (Sumitomo 3M Limited) in the ratios shown in Table 8, and filtering the solution through a 0.1 μm fluororesin filter.

[0206] [Table 8]

[0207] The polymer (RP1), acid generator (PAG1), and basic compound (Amine1) used in the resist top layer material (ArF single layer resist) are shown below. [ka] [ka]

[0208] The immersion protective film material (TC-1) was prepared by dissolving the protective film polymer (PP1) in an organic solvent in the ratio shown in Table 9, and filtering the solution through a 0.1 μm fluorine resin filter.

[0209] [Table 9]

[0210] The polymer (PP1) used in the immersion protective film material (TC-1) is shown below. [ka]

[0211] Next, the film was exposed using an ArF immersion exposure tool (Nikon Corporation; NSR-S610C, NA 1.30, σ 0.98 / 0.65, 35 degree dipole s-polarized illumination, 6% halftone phase shift mask), baked at 100°C for 60 seconds (PEB), and developed in a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 55 nm 1:1 positive line and space pattern.

[0212] Next, the organic anti-reflective film and the CVD-SiON hard mask are etched by dry etching using the resist pattern as a mask using a Telius etching system manufactured by Tokyo Electron, to form a hard mask pattern, the organic film is etched using the obtained hard mask pattern as a mask to form an organic film pattern, and the obtained organic film pattern is used as a mask to form a SiO 2 The film was etched under the following etching conditions.

[0213] Transfer conditions of resist pattern onto SiON hard mask. Chamber pressure 10.0Pa RF power 1,500W CF 4 Gas flow rate: 75sccm O 2 Gas flow rate: 15sccm Time 15sec

[0214] Conditions for transferring hard mask patterns to organic films. Chamber pressure 2.0Pa RF power 500W Ar gas flow rate: 75sccm O 2 Gas flow rate: 45sccm Time 120sec

[0215] Organic film pattern SiO 2 Membrane transfer conditions. Chamber pressure 2.0Pa RF power 2,200W C 5 F 12 Gas flow rate: 20sccm C 2 F 6 Gas flow rate: 10sccm Ar gas flow rate: 300sccm O 2 Gas flow rate: 60sccm Time 90sec

[0216] The cross section of the pattern was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 10.

[0217] [Table 10]

[0218] As shown in Table 10, the results of the organic film forming material of the present invention (Examples 5-1 to 5-22) confirmed that in all cases, the resist upper layer film pattern was finally transferred to the substrate well, and the organic film forming material of the present invention is suitable for use in microfabrication by the multilayer resist method. In Comparative Example 5-3, although the heat resistance was insufficient, a pattern could be formed. Furthermore, in Comparative Examples 5-1 and 5-2, although both the heat resistance and the solvent resistance were insufficient, a pattern could be formed.

[0219] Example 6 Pattern formation test (Examples 6-1 to 6-22, Comparative Examples 6-1 to 6-4) The above organic film-forming materials (UDL-1 to 22, Comparative UDL-1 to 4) were each formed on a SiO 2A coating film was formed in the same manner as in Example 5, except that the coating was applied onto a wafer substrate and baked at 450°C for 60 seconds in a nitrogen stream with an oxygen concentration controlled to 0.2% or less. Patterning and dry etching were then performed, and the shape of the resulting pattern was observed.

[0220] [Table 11]

[0221] As shown in Table 11, in the results of the organic film forming material of the present invention (Examples 6-1 to 6-22), the resist upper layer film pattern was finally transferred to the substrate well in all cases, and it was confirmed that the organic film forming material of the present invention is suitably used for microfabrication by the multilayer resist method. On the other hand, in Comparative Examples 6-1 to 6-4, even though the heat resistance and solvent resistance were ensured, the pattern was poorly filled, so that the pattern collapse occurred during pattern processing, and ultimately a good pattern could not be obtained.

[0222] Example 7 Adhesion Test (Examples 7-1 to 7-22, Comparative Examples 7-1 to 7-4) The above organic film-forming compositions (UDL-1 to 22, Comparative UDL-1 to 4) were each mixed with SiO 2 The solution was applied to a wafer substrate and baked at 450°C for 60 seconds under a nitrogen stream with an oxygen concentration controlled to below 0.2%, forming an organic film with a thickness of 200 nm. The wafer with the organic film was cut into a 1 x 1 cm square, and aluminum pins with epoxy adhesive were attached to the cut wafers using a special tool. The aluminum pins were then attached to the substrate by heating at 150°C for 1 hour in an oven. After cooling to room temperature, the initial adhesion was evaluated by resistance using a thin film adhesion strength measuring device (Sebastian Five-A).

[0223] Figure 5 shows an explanatory diagram of the adhesion measurement method. In Figure 5, 11 is the silicon wafer (substrate), 12 is the cured film, 13 is an aluminum pin with adhesive, 14 is the support base, 15 is the grip, and 16 indicates the tensile direction. The adhesion is the average value of 12 measurements, and the higher the value, the higher the adhesion of the organic film to the substrate. The adhesion was evaluated by comparing the obtained values. The results are shown in Table 12.

[0224] [Table 12]

[0225] As shown in Table 12, the organic film-forming compositions using polyimide (Examples 7-1 to 7-22) have superior adhesion compared to Comparative Example 7-4 that does not have an imide structure, and it is understood that the imide group contained in the polymer main chain contributes to the development of adhesion. The results of the adhesion test also confirmed that the organic film-forming material of the present invention is suitable for use as a pattern formation material.

[0226] From the above, it has become clear that the organic film-forming material of the present invention has heat resistance of 400°C or more even in an oxygen-free inert gas and high-level filling / planarization properties, and is therefore extremely useful as an organic film material for use in a multilayer resist method. It has also become clear that the pattern formation method of the present invention using this material makes it possible to form fine patterns with high precision even if the workpiece is a substrate having steps.

[0227] The present invention is not limited to the above-described embodiment. The above-described embodiment is merely an example, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included in the technical scope of the present invention. [Explanation of symbols]

[0228] 1...substrate, 2...processed layer, 2a...pattern (pattern formed on the processed layer), 3... organic film, 3'... organic film forming material, 3a... organic film pattern, 4...silicon-containing resist intermediate film, 4a...silicon-containing resist intermediate film pattern, 5...resist upper layer film, 5a...resist upper layer film pattern, 6...exposed portion, 7 ... base substrate having a dense hole pattern, 8 ... organic film, 9...Base substrate having a giant isolated trench pattern; 10...Organic film; delta10: step between the trench portion and the non-trench portion of the organic film 10; 11...silicon wafer; 12...hardened coating; 13...aluminum pin with adhesive; 14...support base, 15...grasp, 16...pulling direction.

Claims

1. A pattern forming method comprising the steps of: forming an organic film on a workpiece using an organic film-forming material; forming a silicon-containing resist intermediate film on the organic film using a silicon-containing resist intermediate film material; forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist composition; forming a circuit pattern on the resist upper layer film; transferring the pattern to the silicon-containing resist intermediate film by etching using the resist upper layer film on which the pattern has been formed as a mask; transferring the pattern to the organic film by etching using the silicon-containing resist intermediate film on which the pattern has been transferred as a mask; and further transferring the pattern to the workpiece by etching using the organic film on which the pattern has been transferred as a mask; The pattern forming method is characterized in that the material for forming an organic film contains (A) a polyimide having a repeating unit represented by the following general formula (1A) and an end group represented by any one of the following general formulas (1B) and (1C), and (B) an organic solvent. 【Chemistry 1】 (In the formula, W １ is any tetravalent organic group represented by the following formulas (1F), (K13) to (K18), and W ２ is any divalent organic group represented by the following formulas (1H), (K19) to (K22). 【Chemistry 2】 【Chemistry 3】 (In the formula, R １ is any one of groups represented by the following formula (1D), and two or more R １ may be used in combination.) 【Chemistry 4】 【Chemistry 5】 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】 【Chemistry 12】 【Chemistry 13】 【Chemistry 14】 【Chemistry 15】 【Chemistry 16】

2. a silicon-containing resist intermediate film material being used to form an organic film on a workpiece; a silicon-containing resist intermediate film material being used to form an organic antireflective film on the organic film; a resist upper layer film being used to form a photoresist composition on the organic antireflective film to form a four-layer film structure; a circuit pattern being formed on the resist upper layer film; a pattern being transferred by etching to the organic antireflective film and the silicon-containing resist intermediate film using the resist upper layer film on which the pattern has been formed as a mask; a pattern being transferred by etching to the organic film using the silicon-containing resist intermediate film on which the pattern has been transferred as a mask; and a pattern being further transferred to the workpiece by etching using the organic film on which the pattern has been transferred as a mask; The pattern forming method is characterized in that the material for forming an organic film contains (A) a polyimide having a repeating unit represented by the following general formula (1A) and an end group represented by any one of the following general formulas (1B) and (1C), and (B) an organic solvent. 【Chemistry 17】 (In the formula, W １ is any tetravalent organic group represented by the following formulas (1F), (K13) to (K18), and W ２ is any divalent organic group represented by the following formulas (1H), (K19) to (K22). 【Chemistry 18】 【Chemistry 19】 (In the formula, R １ is any one of groups represented by the following formula (1D), and two or more R １ may be used in combination.) 【Chemistry 20】 【Chemistry 21】 【Chemical 22】 【Chemistry 23】 【Chemistry 24】 【Chemistry 25】 【Chemistry 26】 【Chemical 27】 【Chemistry 28】 【Chemical 29】 【Chemistry 30】 【Chemistry 31】 【Chemistry 32】

3. a photoresist composition for forming a photoresist upper layer film on the inorganic hard mask; ... The pattern forming method is characterized in that the material for forming an organic film contains (A) a polyimide having a repeating unit represented by the following general formula (1A) and an end group represented by any one of the following general formulas (1B) and (1C), and (B) an organic solvent. 【Chemical Formula 33】 (In the formula, W １ is any tetravalent organic group represented by the following formulas (1F), (K13) to (K18), and W ２ is any divalent organic group represented by the following formulas (1H), (K19) to (K22). 【Chemical 34】 【Chemistry 35】 (In the formula, R １ is any one of groups represented by the following formula (1D), and two or more R １ may be used in combination.) 【Chemical 36】 【Chemical 37】 【Chemical 38】 【Chemical 39】 【Chemistry 40】 【Chemistry 41】 【Chemistry 42】 【Chemistry 43】 【Chemistry 44】 【Chemistry 45】 【Chemistry 46】 【Chemistry 47】 【Chemistry 48】

4. a photoresist composition for forming a photoresist pattern on the organic antireflective film; a photoresist composition for forming an organic antireflective film on the organic antireflective film; a photoresist composition for forming an organic antireflective film on the organic antireflective film; a photoresist composition for forming an organic antireflective film on the organic antireflective film; a photoresist composition for forming an organic antireflective film on the organic antireflective film; a photoresist composition for forming an organic antireflective film on the organic antireflective film; a photoresist composition for forming an organic antireflective film on the organic antireflective film; The pattern forming method is characterized in that the material for forming an organic film contains (A) a polyimide having a repeating unit represented by the following general formula (1A) and an end group represented by any one of the following general formulas (1B) and (1C), and (B) an organic solvent. 【Chemistry 49】 (In the formula, W １ is any tetravalent organic group represented by the following formulas (1F), (K13) to (K18), and W ２ is any divalent organic group represented by the following formulas (1H), (K19) to (K22). 【Chemistry 50】 【Chemistry 51】 (In the formula, R １ is any one of groups represented by the following formula (1D), and two or more R １ may be used in combination.) 【Chemistry 52】 【Chemistry 53】 【Chemical 54】 【Chemistry 55】 【Chemistry 56】 【Chemistry 57】 【Chemistry 58】 【Chemistry 59】 【Chemistry 60】 【Chemistry 61】 【Chemistry 62】 【Chemistry 63】 【Chemistry 64】

5. 5. The pattern forming method according to claim 3, wherein the inorganic hard mask is formed by a CVD method or an ALD method.

6. 6. The pattern forming method according to claim 1, wherein the circuit pattern is formed by lithography using light having a wavelength of 10 nm or more and 300 nm or less, direct writing with an electron beam, nanoimprinting, or a combination thereof.

7. 7. The method for forming a pattern according to claim 1, wherein in forming the circuit pattern, the circuit pattern is developed with an alkali developer or an organic solvent.

8. 8. The pattern forming method according to claim 1, wherein the workpiece is a semiconductor device substrate, or a semiconductor device substrate having 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 formed thereon.

9. 9. The pattern formation method according to claim 8, wherein the workpiece contains silicon, titanium, tungsten, hafnium, zirconium, chromium, germanium, copper, silver, gold, aluminum, indium, gallium, arsenic, palladium, iron, tantalum, iridium, cobalt, manganese, molybdenum, or an alloy thereof.

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