TW201248331A - Non-photosensitive resist underlayer film forming composition - Google Patents

Abstract

To provide a novel composition for forming a non- photosensitive resist underlayer film. A composition for forming a non-photosensitive resist underlayer film, which comprises a polymer having a structural unit represented by formula (1) (wherein R1 represents a hydrogen atom, or a methyl group; R2 represents an alkylene group having 1 to 3 carbon atoms, or a phenylene group which may have a substituent; and R3 represents a hydroxy group, or a carboxyl group), a compound having at least two substituents independently selected from the group consisting of a block isocyanate group, a methylol group and an alkoxymethyl group having 1 to 5 carbon atoms, and a solvent.

Description

201248331 VI. [Technical Field] The present invention relates to a non-photosensitive underlayer film which is excellent in alkali developability and has a substantially rectangular cross-sectional shape in a resist pattern formed in an upper layer. A composition and a method of forming a photoresist pattern using a photoresist underlayer film formed of the composition. [Prior Art] In the ion implantation step in the manufacture of a semiconductor device, a step of imparting an impurity ion imparting an n-type or p-type conductivity type to a semiconductor substrate by using a photoresist pattern as a mask may be employed. Therefore, in this step, in order to avoid damage to the surface of the substrate, dry etching is not desired at the time of formation of the photoresist pattern. Therefore, in the formation of the photoresist pattern used in the ion implantation step, the antireflection film which must be removed by dry etching cannot be used under the photoresist. However, in recent years, with the miniaturization, the photoresist used in the ion implantation step also starts to require a fine pattern, and it becomes necessary to have an antireflection film (photoresist underlayer film) of the lower layer of the photoresist. Based on such backgrounds, it is desired to develop a photoresist underlayer film which can be dissolved in a photo-sensitive liquid used for development of a photoresist and can be simultaneously removed by photo-resistance. For example, Patent Document 1 and Patent Document 2 describe a composition for forming an antireflection film capable of simultaneous image removal with a photoresist. The composition is a compound containing polylysine and a compound having at least two epoxy groups as a crosslinking agent-5-201248331 [Prior Art Document] [Patent Document] [Patent Document 1] International Publication No. 2006/027950 [Patent Document 2] International Publication No. 2005/0 22261 [Draft of the Invention] [Problems to be Solved by the Invention] Conventionally, a non-photosensitive photoresist underlayer film dissolved in an alkali developing solution is difficult to form on the photoresist. The cross-sectional shape of the photoresist pattern on the underlayer film is rectangular. The present invention provides a non-photosensitive photoresist underlayer film forming composition for forming a photoresist film under alkali resistive film upon alkali exposure after exposure to form a desired cross-sectional shape. The photoresist pattern is composed of a polymer, a crosslinking agent, a solvent, and other optional components. [Means for Solving the Problem] The non-photosensitive photoresist underlayer film forming composition of the present invention is based on the discovery that a compound having at least two specific substituents is added to an acrylic polymer having a guanamine structure. A photoresist pattern having a cross-sectional shape of approximately rectangular shape is formed on the photoresist underlayer film formed by the composition. That is, the first aspect of the present invention is a non-photosensitive photoresist underlayer film forming composition comprising a polymer having a structural unit represented by the following formula (1), 201248331

0 r R2 I R3 (wherein R1 represents a hydrogen atom or a methyl group, R2 represents an alkylene group having 1 to 3 carbon atoms or a phenyl group which may have a substituent, and R3 represents a hydroxyl group or a carboxyl group), and has a blocked end. A compound selected from the group consisting of an isocyanate group, a methylol group and an alkoxymethyl group having 1 to 5 carbon atoms, and a solvent, and at least two substituents. Further, the second aspect of the present invention is a non-photosensitive resist underlayer film forming composition according to the first aspect, and further has a structural unit represented by the following formula (2) as a structure represented by the above formula (1). Construction unit other than unit =

(wherein R4 represents a hydrogen atom or a methyl group, Y represents a -C(=0)-NH- group or a -C(=0)-〇- group, and X represents a group containing a lactone ring, and contains an adamantane ring. a benzene ring-containing group, the carbon atom of the above-mentioned linking group represented by Υ represents a main chain bond with the above polymer, and the above Υ represents a -C(=0)-NH- group, and the aforementioned X represents a benzene ring-containing group. In the case of the group, the group is excluded as a phenyl group substituted by a hydroxyl group or a carboxyl group. 201248331 The third aspect of the present invention is a non-photosensitive photoresist underlayer film forming composition as described in the first aspect or the second aspect, wherein the compound having at least two substituents has a mass of 1 with respect to the polymer. % to 40% by mass The fourth aspect of the present invention is a non-photosensitive photoresist underlayer film forming composition as described in any of the first to third states, which further contains a crosslinking catalyst. Further, the fifth aspect of the present invention is a non-photosensitive photoresist underlayer film forming composition as described in any of the first to fourth aspects, which further contains a surfactant. [Effect of the Invention] By using the composition of the present invention, the following effects can be obtained: 1) The formed underlying photoresist film is resistant to the photoresist solvent, so that it does not mix with the photoresist film formed on the upper layer, 2 The photoresist underlayer film formed is soluble in the alkali developing solution, so that it can be removed simultaneously with the photoresist film, and 3) the cross-sectional shape of the photoresist pattern formed on the photoresist underlayer film can be formed. The rectangular underlayer film formed by 4) can be removed without dry etching, and thus can be applied to the fabrication of a semiconductor element including a step of ion implantation step or the like which is sensitive to surface damage caused by dry etching. [Embodiment] The polymer -8-201248331 constituting the non-photosensitive resist underlayer film composition of the present invention has the above formula 1 to 3 or a carboxyl group. For example, as for the polymer of the formula (1-1), the formula of the above formula (1-1) alone contains the formula above.

OH (1-1) The structural unit represented by the above (1). In (1), R1 represents a hydrogen atom or a methyl group, and R2 represents an alkylene group which may not have a carbon atom or a phenyl group which may have a substituent, and r3 represents an alkylene group having 1 to 3 carbon atoms. A methyl group, a propyl group, a substituent alkyl group or a halogen group in a phenyl group which may have a substituent. An example of the structural unit represented by the above formula (1) is a specific example of the following formula (1-2) and formula (1-3). Further, the structural unit represented by the above formula (1) may be one structural unit represented by only one (1), or may be composed of two (1) plural structural units.

(1-3) 200,000 , ^ Molecular weight is less than the weight average styrene as [good 3, 〇〇〇 to 200,000. When the weight of the polymer is 1,000 on average, solvent resistance may be insufficient. Further, the sub-quantity is obtained by gel permeation chromatography (G P C ) using a poly standard sample. The polymer may be a copolymer having a structural unit represented by the above formula (2). In the above formula (2), R4 represents a hydrogen atom or a methyl group, Y represents a 〇(=0)-NH- group or a -C(=0)-0- group, and X represents a group containing a lactone ring, and contains a diamond. a group of an alkane ring or a group containing a benzene ring. When X represents a group containing a lactone ring or a group containing an adamantane ring, the lactone ring and the adamantane ring may have a substituent such as a hydroxyl group or a carboxyl group. However, Y represents -c ( =0 ) -NH- group, and X represents a group containing a benzene ring, and the group containing a benzene ring is a phenyl group substituted by a hydroxyl group or a carboxyl group. The above lactone ring is not limited to a 5-membered ring such as r-butyrolactone, and may be a 6-membered ring such as <5-valerolactone, a 7-membered ring such as e-caprolactone. The aforementioned lactone ring may constitute a part of a bicyclic or polycyclic ring (e.g., a tricyclic ring) and may bond to other rings. As an example of the structural unit represented by the formula (2), specific examples of the following formulas (2-1) to (2-9) are exemplified. In addition, as the structural unit represented by the above formula (2), only one structural unit represented by the formula (2) may be contained alone, or two or more plural structural units represented by the formula (2) may be contained - 10- 201248331 【化4】

In the above polymer, the ratio of the structural unit represented by the above formula (1) to the structural unit represented by the former branch in the case of the unit of the above formula (2) is 99:1 in terms of a molar ratio. Further, the adjustment of the development speed of the single-line structure such as the photoresist underlayer film represented by the above formula (2) and the affinity with the substrate are further included. The non-photosensitive photoresist underlayer film forming composition of the present invention has a compound having at least two substituents as a crosslinking agent, and the content is, for example, from 1% by mass to 40%, preferably from 10% by mass to 30% by mass based on the polymer. % » The aforementioned compound having at least two substituents is a blocked isocyanate group, a hydroxymethyl group and a carbon number of 1 to 5, which are represented by the formula (2) 4 0: 60 0, which can be advanced or advanced. The aforementioned action of the film, which is [% by weight, more like a nitrogen-containing compound having a substituent selected from the group consisting of the alkoxymethyl-11 - 201248331 group but having no epoxy group or having at least one aryl group. Compound. As the aforementioned aryl group, for example, a phenyl group or a naphthyl group is exemplified. In the present specification, the term "having at least two substituents" means that each of the compounds contains two or more alkoxymethyl groups having a blocked isocyanate group, a methylol group and a carbon number of 1 to 5, or a combination thereof. A compound of the above substituents. When the compound having at least two substituents has at least two blocked isocyanate groups as a substituent, specific examples thereof include, for example, ΤΑΚΕΝΑΤΕ[registered trademark]Β-8 3 0, ΤΑΚΕΝΑΤΕ Β-8 70Ν. (Mitsui Chemical Co., Ltd.), VEST AN AT [registered trademark] Β 1 3 5 8/ 1 00 (made by EVONIK DEGUSSA). The above-mentioned blocked isononanoate group is a compound which is blocked by a suitable protecting group by an isogastric acid vine group (-N = C = 0). As the blocking agent, for example, methanol, ethanol, isopropanol, n-butanol, 2-ethoxyhexanol, 2-N,N-dimethylaminoethanol, 2-ethoxyethanol, cyclohexanol are exemplified. Alcohols, phenols such as phenol, o-nitrophenol, p-chlorophenol, o-cresol, m-cresol, p-cresol, etc., decylamine such as ε-caprolactam, acetone Anthraquinones such as hydrazine, methyl ethyl ketone oxime, methyl isobutyl ketone oxime, cyclohexanone oxime, acetophenone oxime, benzophenone oxime, pyrazole, 3,5-dimethylpyrazole, a pyrazole such as 3-methylpyrazole, a mercaptan such as dodecyl mercaptan or benzene mercaptan. When the compound having at least two substituents has at least two methylol groups or an alkoxymethyl group having 1 to 5 carbon atoms as a substituent, a specific example thereof is, for example, NIKALAC [registered trademark] ΜΧ-280. , -12- 201248331 NIKALAC MX-270, NIKALAC MX-290 (Sanhe Chemical Co., Ltd.), CYMEL [registered trademark] 303, CYMEL 1 123, POWDERLINK [registered trademark] 1174 (above is 曰 CYTECH INDUSTRIES) )), TML-BPA-MF, TML-BPAF-MF (above is the state chemical industry (stock) system). The compound having at least two substituents may be a mixture of two or more kinds of compounds, or a mixture of oligomers obtained by condensation of the compound itself. The non-photosensitive photoresist underlayer film forming composition of the present invention may contain a crosslinking catalyst which promotes the crosslinking reaction as an optional component. As the cross-linking catalyst, for example, 5-sulfosalicylic acid, p-toluenesulfonic acid, pyridinium-p-toluenesulfonate, trifluoromethanesulfonic acid, camphorsulfonic acid, 4-chlorobenzenesulfonic acid are exemplified. , 4-hydroxybenzenesulfonic acid, benzenedisulfonic acid, 1-naphthalenesulfonic acid, salicylic acid, citric acid, benzoic acid, hydroxybenzoic acid. These crosslinking catalysts may be added alone or in combination of two or more. 1质量质量至1质量质量的质量为为为质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量质量为It is preferably from 0.5% by mass to 5% by mass, more preferably from 1% by mass to 3% by mass. The non-photosensitive photoresist underlayer film forming composition of the present invention may contain, as an optional component, a surfactant for improving the applicability to the substrate. As the surfactant, for example, polyoxyl ether ethyl lauryl ether, polyoxyethylene ethyl stearyl ether, polyoxyethyl methyl cetyl ether, polyoxyethylene ethyl oleyl ether, and the like are exemplified. Ethylene alkyl ethers, polyoxyethylene ethyl octyl phenol ether, polyoxyl extension-13- 201248331 ethyl decyl phenol ether and other polyoxyalkylene aryl ethers, polyoxyethylene • Polyoxypropylene propylene block copolymers, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, Yamanashi Sorbitol fatty acid esters such as sugar anhydride trioleate, sorbitol wild tristearate, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan Monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, polyoxyethyl sorbitan tristearate, etc. Non-ionic surfactants such as polyoxyethylene ethyl sorbitan fatty acid esters EF TOP [registered trademark] EF301, EF TOP EF3 0 3, EF TOP EF3 52 (Mitsubishi Materials E-Chemical Co., Ltd. (formerly JEMCO (share)), MEGAFAC [registered trademark] F171, MEGAFAC F173, MEGAFAC R3 0 (DIC Co., Ltd. (formerly Dainippon Ink Chemical Industry Co., Ltd.)), FLUORAD FC43 0 , FLUORAD FC43 1 (Sumitomo 3M (share) system), ASAHI GUARD [registered trademark] AG710, SURFLON [registered trademark] S-3 8 2, SURFLON SC101, SURFLON SC 102, SURFLON SC103, SURFLON SC104, SURFLON SC105, SURFLON SC106 A fluorine-based surfactant such as Asahi Glass Co., Ltd., an organic siloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). These additives may be added singly or in combination of two or more. When the surfactant is used, the content of the surfactant is, for example, 3% by mass or less, preferably less than 1% by mass, based on the polymer contained in the non-photosensitive photoresist underlayer film forming composition of the present invention. 'More preferably 0.5% by mass or less. -14 - 201248331 The non-photosensitive photoresist underlayer film forming composition of the present invention contains other additives. For example, it may contain an adjusting agent for adjusting the developing liquid, and as the adjusting agent, for example, 1,1,1-phenylene)ethane is exemplified. The non-photosensitive photoresist underlayer film forming composition of the present invention can be prepared by dissolving each component in a suitable solvent to form a homogeneous solution to such a solvent, and for example, ethylene glycol monomethyl ether, ethylene glycol, and methyl cellulose fiber can be used. Acetate, ethyl cellosolve acetate, diethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate xylene, Methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-hydroxy, ethyl 2-hydroxy-2-methylpropanoate, ethyl ethoxylate, hydroxy ester, 2-hydroxy-3-methylbutyl Methyl ester, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, ethyl pyruvate, ethyl acetate, Butyl acetate, butyl lactate, hydrazine, hydrazine-dimethylformamide, hydrazine, hydrazine-dimethylhydrazine-methyl-2-pyrrolidone. These solvents may be used singly or in combination. Further, a high boiling point solvent such as butanediol monoglycol monobutyl ether acetate may be mixed in the solvent. The proportion of the non-photosensitive photoresist underlayer film-forming composition of the present invention is not particularly, for example, 5 to 50% by mass, or 1 to 40% by mass to 30% by mass, as long as the components are uniformly dissolved in the solvent. quality%. The solid content is a solubility of a component remaining from the solvent for removing the solvent from the underlying photoresist film forming composition of the present invention (4-hydroxyl group is used in the upper state. Alcohol monoethyl ether glycol monomethyl propylene glycol mono, toluene, Ethyl propionate ethyl acetate, 3-methoxymethyl ester, ethyl lactic acid ethyl acetamide and two kinds of solids with dibutyl ether and C, but the amount of i, or non-photosensitive -15-201248331 The composition to be prepared is preferably used after filtration using a filter having a pore diameter of, for example, about 0.2 m. The non-photosensitive photoresist underlayer film forming composition of the present invention is also excellent in storage stability at room temperature for a long period of time. A method for forming a photoresist pattern by forming a composition under a photosensitive photoresist, comprising coating the composition on a semiconductor substrate and baking to form a photoresist underlayer film, and forming a photoresist film on the underlying photoresist film to enable The photoresist underlayer film and the photoresist substrate coated with the photoresist film are exposed, and the photoresist film and the photoresist underlayer film are developed after exposure. Hereinafter, the non-photosensitive photoresist underlayer film of the present invention is applied. The composition of the composition is described in detail, for example, a semiconductor substrate such as a tantalum film coated with a hafnium oxide film, a semiconductor substrate coated with a tantalum nitride film or a tantalum nitride film, a tantalum nitride substrate, a quartz substrate, or the like. The composition of the present invention is applied onto a glass substrate (including an alkali-free glass, a low-alkali glass, a crystallized glass, a glass substrate on which an ITO film is formed, etc.) by a suitable coating method such as a spinner or an applicator, and then used. The heating means such as a heating plate is baked to form a photoresist underlayer film. The baking condition is appropriately selected from the baking temperature of 80 ° C to 250 ° C and the baking time of 0.3 minutes to 10 minutes. Preferably, the baking temperature is from 120 ° C to 25 CTC, and the baking time is from 0.5 to 5 minutes. Here, as the film thickness of the photoresist lower layer film, it is y 5 m to 3.0 / zm, for example, 〇.〇l" m to 0.05 " m, or 0.05/zm to 〇.l" m. When the temperature at the time of baking is less than the above range, the crosslinking becomes insufficient, and there is a case where it is mixed with the photoresist film formed on the upper layer. On the other hand, the temperature at the time of baking is higher than the above range The photo-resist film may be formed on the underlying film of the photoresist, and the photoresist film may be formed by the decrease in the imageability or the cross-linking of the cross-linking film. -16- 201248331 The photoresist can be applied to the underlayer film of the photoresist and baked by a general method. The photoresist used in the formation of the photoresist film can be photosensitive to the light used for exposure. There is no particular limitation, and either a negative type or a positive type can be used. For example, a positive type resist composed of a phenol resin and 1,2-naphthoquinonediazide sulfonate is improved by utilizing acid decomposition. A chemically amplified photoresist composed of an alkali dissolution rate-based binder and a photoacid generator, which is a low molecular compound and an alkali-soluble binder and a photoacid generator which improve the alkali dissolution rate of the photoresist by acid decomposition. The chemically amplified photoresist is composed of a binder having a base for increasing the alkali dissolution rate by acid decomposition, and a low molecular compound and a photoacid generator having an alkali dissolution rate of the photoresist by acid decomposition. Amplifying photoresist . For example, the trade name of Rohm and Haas Electronic Materials Co., Ltd.: APEX-E, Sumitomo Chemical Co., Ltd., trade name: PAR7 10, and Shin-Etsu Chemical Co., Ltd.

SEPR430, trade name of Tokyo Chemical Industry Co., Ltd. TDUR-P343 5LP 时 When a photoresist pattern is formed, exposure is performed by a mask (mask) for forming a specific pattern. For exposure, for example, a KrF excimer laser or an ArF quasi-molecular laser can be used. After exposure, post exposure heat preservation (Post Exposure Bake) is performed as needed. The conditions for "heating after exposure" are appropriately selected from the heating temperature of 80 ° C to 150 ° C and the heating time of 0.3 minutes to 10 minutes. Subsequently, a photoresist pattern is formed by the step of developing with an alkali developing solution. Since the photoresist underlayer film formed of the composition of the present invention is soluble in the alkali image -17-201248331 liquid, after exposure, the two layers of the photoresist film and the film can be imaged together by an alkali developing solution. The alkali imaging solution may, for example, be an aqueous solution of potassium hydroxide, an alkali metal hydroxide of hydrogen, an aqueous solution of tetraammonium hydroxide such as tetramethylammonium hydroxide, ethylammonium or choline, or ethanol, or An alkaline aqueous solution such as an aqueous amine solution such as a diamine. Further, a surfactant may be added to the liquid. As for the development conditions, it is appropriately selected from the development temperature of 5 ° C to 50 ° C, and 1 〇 to 300 seconds. The photoresist underlayer film formed of the photoresist underlayer film of the present invention can be used in a photoresist solution for 2.38 mass% of tetramethylammonium hydroxide aqueous solution, which can be imaged at room temperature. [Examples]

Hereinafter, specific examples of the non-photosensitive layer film-forming composition of the present invention will be described using the following examples. However, the present invention is not limited to the apparatus used for the weight average measurement of the polymer obtained in the following synthesis examples. Device: liquid feeding pump (TOSOH (share 8020), degassing device (SD-8022 manufactured by the company), CO-8020 manufactured by Tube Co., Ltd.), differential refractive index detector (same as RI-8 02 0), automatic Sampler (AS-8020, manufactured by the company) GPC Pipe column: Asahipak [registered trademark] GF-310HQ, GF-510HQ > Asahipak GF-710HQ Column temperature: 4 (TC photoresist lower layer of sodium hydroxide such as tetraamine The developmental imaging time of propylamine is made up of easy-to-use photoresist. Molecular weight DP-column oven (Company made by Asahipak -18- 201248331 Flow: 0.6ml/min)

Eluent··l〇mmol/l LiBr/DMF <Synthesis Example 1> 4-hydroxyphenylmethacrylamide 8.0 g, r-butenoate 3.3 g, 2,2,-azo-isobutyl After the nitrile enthalpy. 8 g was dissolved in propylene ～ 赛 赛 赛 〜 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 。 。 。 。 。 。 。 。 。 。 。 。 。 Subsequently, the polymer was dried under reduced pressure using ethyl acetate eq. & precipitation to obtain a polymer having a structural unit represented by ruthenium. The average molecular weight of the obtained polymer was 9,000 in terms of standard polystyrene. 【化5】

<Synthesis Example 2> 5.0 g of 4-hydroxyphenylmethacrylamide, N-phenylmethacrylamide 0.88, 2,2'-azoisobutyronitrile 〇.68 was dissolved in propylene glycol monomethyl ether After 17^, the solution was stirred for 15 hours under heating of 801. Subsequently, the polymer was precipitated using ethyl acetate, and the polymer was dried under reduced pressure to obtain 5 g of a polymer having a structural unit represented by the following formula (5). The weight average molecular weight of the obtained polymer was 1,100 00 in terms of standard polystyrene. -19- 201248331

<Synthesis Example 3> 5.0 g of 4-hydroxyphenyl methacrylate (Showa Polymer Co., Ltd.), 2.0 g of r-butyrolactone methacrylate, and 2,2'-azoisobutyronitrile After dissolving 5 g of propylene glycol monomethyl ether in 30 g, the solution was added dropwise to a flask heated to reflux with 113 g of propylene glycol monomethyl ether over 2 hours. Subsequently, the polymer was precipitated using a mixed solution of ethyl acetate:hexane = 6:4, and the polymer was dried under reduced pressure to obtain 5 g of a polymer having a structural unit represented by the following formula (4). The weight average molecular weight of the obtained polymer was 13,000 in terms of standard polystyrene. 【化7】

(5) <Synthesis Example 4> (Synthesis of polylysine) -20- 201248331 4,4,-(hexafluoroisopropylidene)bisbenzoic acid mono- 3,5-diaminobenzoic acid 3.128, bis(4-aminophenyl)nonanediol monomethyl ether 145_6g in a 'reaction at 80 ° C for 20 hours' solution of poly-proline acid [A]. The obtained polyamic acid had the following structural unit of the following formula (7), and the weight average was 3,400 in terms of polystyrene.旰 17.8g, 4.92g in C, this is obtained by the standard (6)

【化8】COOH

<Synthesis Example 5> (Synthesis of light absorbing compound) 3,7-dihydroxy-2-naphthoic acid 19. (^, ginseng (2,3-cyclo)isocyanurate l〇g and benzyl chloride The solution (a) containing a light-absorbing property of the compound represented by the following formula (8) is obtained by reacting at a temperature of 130 ° C for 1 4 8 g at a temperature of 130 ° C for 1 4 8 g. Oxypropyl group in cyclohexanone conjugate (to -21 - 201248331

【化9】 HO

<Example 1> (Preparation of photoresist underlayer film forming composition) In 0.2 g of the polymer represented by the formula (3) obtained in Synthesis Example 1, a mixed isocyanate-based crosslinking agent (Mitsui Chemical Co., Ltd.) ), product name: TAKEN ATE [registered trademark] B-830) 0.04 g, dissolved in 15.8 g of propylene glycol monomethyl ether to form a solution. Subsequently, it was filtered using a polyethylene microfilter having a pore size of 2.2; zm to prepare a photoresist underlayer film forming composition (solution). <Example 2> (Preparation of photoresist underlayer film forming composition) In the polymer O.lg represented by the formula (3) obtained in Synthesis Example 1, 'mixed amine-based plastic crosslinking agent (Sanhe Chemical Co., Ltd.) ), trade name: NIKALAC [registered trademark] MX-280) O.Olg and 0.002g of 5-sulfosalicylic acid dihydrate as cross-linking catalyst, dissolved in propylene glycol monomethyl ether 7'4g -22- In 201248331 it becomes a solution. Subsequently, it was filtered using a polyethylene microfilter having a pore size of 0.2 to prepare a photoresist underlayer film forming composition (solution). <Example 3> (Preparation of a photoresist underlayer film forming composition) In the polymer 〇.g represented by the formula (4) obtained in Synthesis Example 2, a mixed isocyanate crosslinking agent (manufactured by Mitsui Chemicals Co., Ltd.) , trade name: ΤΑΚΕΝΑΤΕ [registered trademark] B-830) 0.02g, dissolved in propylene glycol monomethyl ether 8.5g into a solution" followed by filtration using a polyethylene microfilter with a pore size of 0.2 / zrn, modulation of the formation of photoresist under the film formation (solution). <Comparative Example 1 > (Preparation of photoresist underlayer film forming composition) In the polymer 〇.2g represented by the formula (5) obtained in Synthesis Example 3, an isocyanate crosslinking agent was mixed (Mitsui Chemical Co., Ltd.) The product name: ΤΑΚΕΝΑΤΕ [registered trademark] B-830) 0.04 g, dissolved in propylene glycol monomethyl ether 15.8 g to form a solution. Subsequently, it was filtered using a polyethylene microfilter having a pore size of 0.2 / zm to prepare a photoresist underlayer film forming composition (solution). <Comparative Example 2 > (Preparation of photoresist underlayer film forming composition) In the polymer 〇·1 g represented by the formula (5) obtained in Synthesis Example 3, a mixed amine-based plastic crosslinking agent (Sanwa Chemical) (Stock) system, trade name: NIKALAC [registered trademark] MX-280) O.Olg and 5-sulfosalicylic acid di-23- 201248331 hydrate 〇.〇〇2g, dissolved in propylene glycol monomethyl ether 7.4g Become a solution. Subsequently, it was filtered using a polyethylene microfilter having a pore size of 0.2 / zm to prepare a photoresist underlayer film forming composition (solution). <Comparative Example 3 > (Preparation of photoresist underlayer film forming composition) To 20 g of the polyamine acid-containing solution [A] obtained in Synthesis Example 4, a solution containing the light absorbing compound obtained in Synthesis Example 5 was added. a] 6.5g, hydroxyphenyl ethane oxime. 3g 'epoxy cross-linking agent (made by Dongdu Chemical Co., Ltd., trade name: YH434L) l.lg, propylene glycol monomethyl ether 121g, propylene glycol monomethyl ether acetate The ester (154 g) and cyclohexanone Ug were stirred at room temperature for 30 minutes to prepare a photoresist underlayer film forming composition (solution). [Evaluation of the development of the photoresist underlayer film and the dissolution test of the solvent of the photoresist] The developer (manufactured by Tokyo Ohka Kogyo Co., Ltd., trade name: NMD-3, 2.38 mass% aqueous solution of tetramethylammonium hydroxide) Evaluation of Solubility of Each of the photoresist lower layer film formation compositions prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was applied to a semiconductor substrate (tantalum wafer) by a spinner. Subsequently, the semiconductor substrate was baked at a temperature of 5 ° C for 1 minute from 130 ° C to 190 ° C on a hot plate to form a photoresist underlayer film (film thickness 〇 4 μm). The formed film-attached wafer was immersed in the developing solution for 1 minute to confirm the solubility in the developing solution. After immersion, it was rinsed with water, and dried by blowing with nitrogen gas to confirm the residual film. In Table 1 below, the solubility in the developing solution during immersion in the developing solution and the baking of the residual film were not confirmed after the development -24 - 201248331. In Table 1, when the film was uniformly dissolved during development and the residual film of the photoresist underlayer film was not confirmed after development, the solubility of the developing solution was evaluated as "good", and on the other hand, the underlayer film of the photoresist was not uniform at the time of development. When it was dissolved, it was observed that when the undissolved film was peeled off from the semiconductor substrate (peeling phenomenon), or when the residual film was confirmed after development, it was evaluated as "poor". Next, a dissolution test on the photoresist solvent was carried out. Each of the photoresist underlayer film formation compositions prepared in Examples 1 to 3 and Comparative Examples 1 to 3 was applied onto a semiconductor substrate (tantalum wafer) by a spinner. Then, the film was baked on the hot plate for 1 minute under the "baking temperature at which the residual film was not observed after development" as shown in Table 1, to form a photoresist underlayer film (film thickness: 0.04 Vm). The photoresist underlayer film was immersed in the solvent propylene glycol monomethyl ether acetate used in the photoresist for 1 minute. The evaluation results are shown in Table 1 below. In Table 1, when the film thickness change of the photoresist film before and after immersion in propylene glycol monomethyl ether acetate was less than 1%, the solvent resistance was evaluated as "Yes", and when the film thickness change was 1% or more, it was evaluated as " no". [Table 1] The baking temperature of the residual film was not confirmed after the development of the developing solution of the developing solution. Example 1 Good 185 〇 C Example 2 Good 130 ° C Example 3 Good 195 〇 C Comparative Example 1 Good 150 ° C ^ττΤ - No Comparative Example 2 Poor (peeling phenomenon) 130 ° C Comparative Example 3 Good 185 ° C Yes -25 - 201248331 [Optical parameter test] Examples 1 to 3 and Comparative Example 3 Each of the modulated underlayer film forming compositions is applied onto a semiconductor substrate (tantalum wafer) by a spinner. Subsequently, Example 1 and Comparative Example 3 were baked at 丨 8 5 ° C, and Example 2 at 13 (TC, Example 3 on a hot plate at 195 ° C for 1 minute to form a photoresist underlayer film (film thickness 〇· 〇5// m ). Next, the photoresist underlayer film was measured using a photolithography meter (VUV-VASE VU-302, manufactured by JA Woollam Co., Ltd.) to measure the refractive index (n値) and the attenuation coefficient at wavelengths of 248 nm and 193 nm ( k値). The evaluation results are shown in the following Table 2. [Table 2] 248 nm 193 nm refractive index (η値) attenuation coefficient (k値) refractive index (η値) attenuation coefficient (k値) Example 1 1.72 0.21 1.60 0.36 Example 2 1.67 0.19 1.63 0.36 Example 3 1.77 0.30 1.57 0.48 Comparative Example 3 1.79 0.42 1.49 0.43 [Evaluation of pattern shape] Each of the photoresist underlayer films prepared in Examples 1 to 3 and Comparative Example 3 was formed into a composition. The object was coated on a semiconductor substrate (twisted wafer) using a spinner. Subsequently, Example 1 was baked at 185 ° C, Example 3 at 195 ° C, and Comparative Example 3 at 1 85 ° C for 1 minute. Forming a photoresist underlayer film (film thickness 0.04/zm) » On the underlayer film of the photoresist, a commercially available photoresist solution was coated with a spinner (East The chemical industry (stock) system, trade name TDUR-P343 5 LP), heated on a hot plate at 90 ° C for 1 minute to form a photoresist film -26- 201248331 (film thickness 0.265 / zm). Then use NIKON (shares) The S205C lens scanning type exposure machine (stepper) (wavelength 248nm: 0.75 > 〇: 0.85 (CONVENTIONAL)), by setting the line width of the image after the photoresist pattern and the width between the lines is 0.20 / zm The exposure was carried out, and then, the post-heating was performed for 1 minute on a hot plate at U0 ° C. After cooling, a 0.26 equivalent concentration of aqueous tetramethyl hydroxide solution was used as a developing solution for development. After development, scanning was performed. The cross section perpendicular to the substrate was observed by an electron microscope (SEM). The obtained cross-sectional SEM is shown in Fig. 1 (Example 1), Fig. 2 (Example 3), and Fig. 3 (Example 3). When the composition of the underlayer film formed in Examples 1 and 3 was used, the cross-sectional shape of the obtained resist pattern was 1 and approximately rectangular as shown in Fig. 2. On the other hand, it was used to compare the modulated light. When the underlayer film is formed to form a composition, the shape of the obtained photoresist pattern is under the photoresist The vicinity of the interface between the layers is a knob shape, and is rectangular as shown in Fig. 3. [Schematic description of the drawings] Fig. 1 is a cross-sectional view showing the shape of the photoresist pattern obtained by using the photoresist underlayer film formed by Example 1. SEM photo. Fig. 2 is a cross-sectional SEM photograph showing a resist pattern shape obtained by using the photoresist underlayer film formed in Example 3. Fig. 3 is a cross-sectional SEM photograph showing the shape of a resist pattern obtained by using the photoresist film underlayer film prepared in Comparative Example 3. NSR-, NA is the mask, 1 exposure, ammonium, light, photo, comparison, light, as shown in Figure 3, section, no group, group, group, -27-

Claims (1)

201248331 VII. Patent application scope: 1. A non-photosensitive photoresist underlayer film forming composition comprising: a polymer having a structural unit represented by the following formula (1) in the stomach and stomach [Chemical Formula 1] (wherein R1 represents a hydrogen atom or a methyl group, R2 represents an alkylene group having 1 to 3 carbon atoms or a phenyl group which may have a substituent, and R3 represents a hydroxy group or a fluorenyl group), and has a blocked isocyanate. a compound of at least two substituents selected from the group consisting of a hydroxymethyl group and an alkoxymethyl group having 1 to 5 carbon atoms, and a solvent. 2. The non-photosensitive photoresist underlayer film forming composition according to the first aspect of the invention, wherein the polymer further has a structural unit represented by the following formula (2): (2) X (wherein R4 represents a hydrogen atom or a methyl group 'Y represents -c(=o)-NH- group or ·(:(=〇)-〇-yl group, and X represents a group containing a lactone ring, a group containing an adamantane ring or a The phenyl ring group 'the carbon atom of the above-mentioned linking group represented by γ represents a main chain linkage with the aforementioned polymer' and the aforementioned Y represents a - c(=o -28- 201248331 )-NH- group, and the aforementioned X represents a benzene group. When the base of the ring is 'excluding a phenyl group substituted with a hydroxy group or a carboxy group, the base is formed by a hydroxy group or a carboxy group. 3. A non-photosensitive photoresist underlayer film forming group according to claim 1 or 2, wherein The above-mentioned compound having at least two substituents is contained in an amount of from 1% by mass to 40% by mass based on the above-mentioned polymer. 4. The non-photosensitive photoresist underlayer film forming composition according to any one of claims 1 to 3, Further, it contains a crosslinking catalyst. 5. Non-photosensitive photoresist underlayer film forming composition according to any one of claims 1 to 4. Which further contains a surfactant. -29-