WO2012046917A1 - (meth)acrylate-based polymer and photosensitive resin composition including same - Google Patents

Abstract

Provided are a (meth)acrylate-based polymer and a photosensitive resin composition including same.

Description

(Meth) acrylate type polymer and the photosensitive resin composition containing the same

The present disclosure relates to a (meth) acrylate polymer and a photosensitive resin composition comprising the same.

As the degree of integration of semiconductor chips increases, the formation of fine patterns for sub-micron chips in a lithography process is required. In particular, in the lithography process for fabricating ultra-high density circuits, shorter wavelengths (DUV regions) are used to achieve higher resolution. As a result, a lithography technology using shorter wavelengths of deep ultraviolet rays than the conventional g-line (436 nm) and i-line (365 nm) has been introduced. For this purpose, a new concept of material, a high sensitivity and high resolution chemically amplified resist, has been introduced. It became.

Since the resin of the chemically amplified resist using deep ultraviolet ray must be transparent to the light source used and the resin having a good protection reaction, a polyhydroxy styrene is used for the KrF (248 nm) resist, and ArF An acrylate polymer is used for the (193 nm) resist, and a polymer including a hydrocarbon ring compound such as adamantyl in the side chain portion of the ester group is used to compensate for the insufficient etch resistance compared to the KrF resist.

However, when a hydrocarbon ring compound such as adamantyl is used as in the prior art, when the resin is not sufficiently soluble, scum occurs after the pattern is implemented or the pattern is not formed well due to poor adhesion with the substrate. There was.

One aspect of the present invention is to provide a (meth) acrylate-based polymer that can produce a resin film that is excellent in adhesion to a substrate and excellent in implant resistance without generating scum even at a high film thickness. .

Another aspect of the present invention is to provide a photosensitive resin composition comprising the (meth) acrylate-based polymer.

One aspect of the present invention provides a (meth) acrylate-based polymer comprising a repeating unit represented by the following formula (1) to (3).

[Formula 1]

(In Formula 1,

R ¹ includes hydrogen or a methyl group, R ¹⁰ includes a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 heterocycloalkyl group, n is an integer from 0 to 3.)

[Formula 2]

(In Formula 2,

R ² comprises hydrogen or a methyl group, R ²⁰ comprises an ester group and comprises a substituted or unsubstituted C3 to C20 cycloalkyl group.)

[Formula 3]

(In Chemical Formula 3,

R ³ contains hydrogen or a methyl group, and R ³⁰ includes a t-butyl group, triethylcarbyl group, 1-methyl cyclohexyl group, 1-ethylcyclopentyl group, t-amyl group or acetal group.)

The repeating unit represented by Formula 1 may include any one of the repeating units represented by the following Formulas 4 to 23.

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

[Formula 22]

[Formula 23]

In the definition of R ¹⁰ in Formula 1, the heterocycloalkyl group may include a hetero atom of oxygen (O) or nitrogen (N).

R ²⁰ in Formula 2 is a gamma-butyrolactonyl group, a valerolactonyl group, a 1,3-cyclohexanecarbolactonyl group, 2,6 Norbornanecarbolacton-5-yl (2,6-norbornanecarbolacton-5-yl) or 7-oxa-2,6-norbornanecarbolactone-5-yl (7-oxa-2,6-norbornanecarbolacton -5-yl) group.

The (meth) acrylate-based polymer may have a weight average molecular weight of 3,000 to 20,000 g / mol, dispersion degree may be 1.3 to 2.5.

The (meth) acrylate-based polymer, 10 to 40 mol% of repeating units represented by Formula 1; 20 to 60 mol% of repeating units represented by Formula 2; And it may include 20 to 50 mol% of the repeating unit represented by the formula (3).

Another aspect of the invention the (meth) acrylate-based polymer; Photo acid generator (PAG); And it provides a photosensitive resin composition comprising a solvent.

The (meth) acrylate-based polymer may be included in 5 to 15% by weight based on the total amount of the photosensitive resin composition.

The photoacid generator is triarylsulfonium perfluoroalkylsulfonate, triarylsulfonium triflate, diaryliodonium triflate, triarylsulfonium nonaplate, diaryliodonium nonaplate, succinimidyl tri It may include a plate, 2,6-dinitrobenzyl sulfonate or a combination thereof, the photoacid generator may be included in 1 to 15 parts by weight based on 100 parts by weight of the (meth) acrylate-based polymer.

The photosensitive resin composition may further include 0.1 to 5 parts by weight of an organic amine based on 100 parts by weight of the (meth) acrylate-based polymer, wherein the organic amine is triethylamine, triisobutylamine, trioctylamine, tri Isodecylamine, triethanolamine, hydroxypiperidine or combinations thereof.

Other specific details of embodiments of the present invention are included in the following detailed description.

The (meth) acrylate-based polymer is excellent in solubility in a developer, does not generate scum, and is excellent in implant resistance and dry etch resistance, and has good hydrophilic property, which is excellent in adhesion to a substrate. Less occurrence of lifting. Thereby, the resin film suitable for an ion implantation process can be provided.

1A is a CD-SEM photograph of a 150 nm pattern (optimal energy (E _op )) obtained using the photosensitive resin composition according to Example 1. FIG.

FIG. 1B is a CD-SEM photograph of a 150 nm pattern (2 mJ / cm ² less than the optimal energy (E _op )) obtained using the photosensitive resin composition according to Example 1. FIG.

FIG. 1C is a CD-SEM photograph of a 150 nm pattern (4 mJ / cm ² less than the optimal energy (E _op )) obtained using the photosensitive resin composition according to Example 1. FIG.

2A is a CD-SEM photograph of a 150 nm pattern (optimum energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 1. FIG.

FIG. 2B is a CD-SEM photograph of a 150 nm pattern (2 mJ / cm ² less than the optimal energy E _op ) obtained using the photosensitive resin composition according to Comparative Example 1. FIG.

2C is a CD-SEM photograph of a 150 nm pattern (4 mJ / cm ² less than the optimal energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 1. FIG.

3A is a CD-SEM photograph of a 150 nm pattern (optimum energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 2. FIG.

3B is a CD-SEM photograph of a 150 nm pattern (2 mJ / cm ² less than the optimal energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 2. FIG.

3C is a CD-SEM photograph of a 150 nm pattern (4 mJ / cm ² less than the optimal energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 2. FIG.

4 shows the depth of focus (DOF) margin at the 150 nm pattern (optimum energy (E _op ): 36 mJ / cm ² ) obtained using the photosensitive resin composition according to Example 1 at the center and the edge of the pattern. CD-SEM photo showing.

FIG. 5 shows the exposure latitude (EL) margin of the 150 nm pattern (optimum energy (E _op ): 36 mJ / cm ² ) obtained using the photosensitive resin composition according to Example 1 with respect to the pattern center and edges. FIG. CD-SEM picture.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, by which the present invention is not limited and the present invention is defined only by the scope of the claims to be described later.

Unless otherwise specified herein, "substituted" means that at least one hydrogen atom is a halogen atom (F, Cl, Br or I), hydroxy group, nitro group, cyano group, imino group (= NR, R is hydrogen or C1 to C10 alkyl group), amino group (-NR'R '', R 'and R' 'are each independently hydrogen or C1 to C10'alkyl group), amidino group, azido group, hydrazine group, hydrazone group, carbonyl group, carboxyl group or Salts thereof, sulfonic acid groups or salts thereof, phosphoric acid groups or salts thereof, carbamyl groups, thiol groups, ester groups, C1 to C20 alkyl groups, C2 to C20 alkyl groups, C2 to C20 alkyl groups, C1 to C20 alkyl groups, C3 to C30 Cycloalkyl group, C3 to C30 cycloalkenyl group, C3 to C30 cycloalkynyl group, C2 to C30 heterocycloalkyl group, C2 to C30 heterocycloalkenyl group, C2 to C30 heterocycloalkynyl group, C6 to C30 aryl group, C6 to C30 It means for interrogating an aryl group or a C6 to C30 substituted aryloxy groups.

Unless otherwise specified herein, "heterocycloalkyl group", "heterocycloalkenyl group", "heterocycloalkynyl group", and "heteroaryl group" each have at least one hetero atom of N, O, S or P in the ring compound. It means to be included.

The (meth) acrylate-based polymer according to one embodiment includes a repeating unit represented by the following Chemical Formulas 1 to 3.

[Formula 1]

(In Formula 1,

R ¹ contains hydrogen or a methyl group,

R ¹⁰ comprises a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 heterocycloalkyl group,

n is an integer of 0 to 3)

[Formula 2]

(In Formula 2,

R ² contains hydrogen or a methyl group,

R ²⁰ includes an ester group and includes a substituted or unsubstituted C3 to C20 cycloalkyl group.)

[Formula 3]

(In Chemical Formula 3,

R ³ contains hydrogen or a methyl group,

R ³⁰ includes t-butyl group, triethylcarbyl group, 1-methyl cyclohexyl group, 1-ethylcyclopentyl group, t-amyl group or acetal group.)

The repeating unit represented by Formula 1 has a cyclic alkyl group, thereby improving the etch resistance of the (meth) acrylate-based polymer.

The cyclic alkyl group is a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 heterocycloalkyl group, wherein the substitution may specifically mean substituted with a C1 to C4 alkyl group, more Specifically, it may mean that a methyl group, an ethyl group, n-propyl group, iso-propyl group or the like is substituted.

In addition, the heterocycloalkyl group may specifically include a hetero atom of oxygen (O) or nitrogen (N).

Specific examples of the repeating unit represented by Formula 1 include any one of the repeating units represented by the following Formulas 4 to 23.

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

[Formula 12]

[Formula 13]

[Formula 14]

[Formula 15]

[Formula 16]

[Formula 17]

[Formula 18]

[Formula 19]

[Formula 20]

[Formula 21]

[Formula 22]

[Formula 23]

The repeating unit represented by Formula 1 may be included in 10 to 40 mol%, specifically, 20 to 30 mol% based on the total amount of the (meth) acrylate-based polymer. When the repeating unit represented by Chemical Formula 1 is included in the above range, the etch resistance and the lifting resistance are excellent.

The repeating unit represented by Formula 2 is a monocyclic or polycyclic (meth) acrylate repeating unit including an ester group, which may improve the hydrophilicity of the photosensitive resin composition and improve adhesion to the substrate.

R ²⁰ in Formula 2 may be a lactone derivative. Examples of the lactone derivatives include gamma butyrolactonyl groups, valerolactonyl groups, 1,3-cyclohexanecarbolactonyl groups, and 2,6- Norbornane carbolactone-5-yl (2,6-norbornanecarbolacton-5-yl) group, 7-oxa-2,6-norbornanecarbolactone-5-yl (7-oxa-2,6-norbornanecarbolacton- 5-yl) group etc. are mentioned.

The repeating unit represented by Formula 2 may be included in 20 to 60 mol%, specifically 30 to 50 mol% based on the total amount of the (meth) acrylate-based polymer. When the repeating unit represented by Formula 2 is included in the above range, the adhesion to the substrate is excellent.

The repeating unit represented by Chemical Formula 3 is a (meth) acrylate repeating unit including an acid labile group in which decomposition occurs in the presence of a acidic catalyst, and is decomposed by an acid catalyst generated during exposure to (meth) acrylic acid. The rate-based polymer may help to dissolve well in the alkaline developer.

Examples of the acid-decomposable group include t-butyl group, triethylcarbyl group, 1-methyl cyclohexyl group, 1-ethylcyclopentyl group, t-amyl group, acetal group, and the like, and among them, development speed T-butyl group may be used in the aspect. 　

The repeating unit represented by Formula 3 may be included in 20 to 50 mol%, specifically 30 to 40 mol% based on the total amount of the (meth) acrylate-based polymer. When the repeating unit represented by Formula 1 is included in the above range, the development speed is excellent.

The (meth) acrylate-based polymer comprising a repeating unit represented by Formula 1 to 3 may be a terpolymer, or may be a multipart copolymer further including the same type or different types of repeating units. , Random copolymers, block copolymers, alternating copolymers, branched copolymers, or the like can be used.

The (meth) acrylate-based polymer may have a weight average molecular weight of 3,000 to 20,000 g / mol, specifically 5,000 to 10,000 g / mol. When it has the said weight average molecular weight range, the surface edge roughness (LER) characteristic of the resin film obtained from the photosensitive resin composition is excellent.

Dispersion degree of the (meth) acrylate-based polymer may be 1.3 to 2.5, specifically, may be 1.5 to 2.0. The dispersion degree is a value obtained by dividing the weight average molecular weight by the number average molecular weight. When the (meth) acrylate-based polymer has a dispersion degree in the above range, it is excellent in etch resistance and developability.

The (meth) acrylate polymer is a general radical polymerization method using a repeating unit derivative monomer represented by Formula 1, a repeating unit derivative monomer represented by Formula 2, and a repeating unit derivative monomer represented by Formula 3 By polymerization.

Another embodiment includes a photosensitive resin composition including the (meth) acrylate-based polymer described above.

The photosensitive resin composition includes the (meth) acrylate-based polymer, a photo acid generator, and a solvent.

The (meth) acrylate-based polymer may be included in 5 to 15% by weight, specifically, 7 to 12% by weight based on the total amount of the photosensitive resin composition. When the (meth) acrylate-based polymer is included in the above range can be obtained excellent etch resistance and adhesion.

The photoacid generator may be an inorganic onium salt, organic triflate, organic sulfonate, or a combination thereof.

Examples of the inorganic onium salt include triarylsulfonium salt, diaryl iodonium salt, and the like.

Specific examples of the photoacid generator include triarylsulfonium perfluoroalkylsulfonate, triarylsulfonium triflate, diaryliononium triflate, triarylsulfonium nonaplate, diaryliodonium nonaplate, Succinimidyl triflate, 2,6-dinitrobenzyl sulfonate or combinations thereof.

When using the compound as a photoacid generator, it is possible to improve the process margin and pattern shape by adjusting the strength of the generated acid, acid diffusion rate, absorbance.

The photoacid generator may be included in an amount of 1 to 15 parts by weight, specifically 3 to 8 parts by weight, based on 100 parts by weight of the (meth) acrylate polymer. When the photoacid generator is included in the above range, an excellent exposure amount and transmittance of the photosensitive resin composition can be obtained.

As the solvent, propyleneglycol monomethylether acetate (PGMEA), propyleneglycol monomethylether (PGME), ethyl lactate (EL), cyclohexanone, 2-heptanone (2 -heptanone) etc. can be used 1 type or in mixture of 1 or more types.

The solvent may be included in the remainder with respect to 100 parts by weight of the (meth) acrylate-based polymer, specifically, may be included in 80 to 95 parts by weight. When the solvent is included in the above range, the film thickness uniformity of the photosensitive resin composition may be excellent when applied to a wafer, and coating failure may be reduced.

The photosensitive resin composition may further include an organic amine as a quencher for the purpose of controlling the exposure dose and forming an excellent profile together with the constituent components.

The organic amine may be an amine compound, and examples thereof include triethylamine, triisobutylamine, trioctylamine, triisodecylamine, triethanolamine, hydroxypiperidine, or a mixture thereof.

The organic amine may be included in an amount of 0.1 to 5 parts by weight, and specifically 0.5 to 3 parts by weight, based on 100 parts by weight of the (meth) acrylate-based polymer. When the organic amine is included in the above range, it is possible to control the depth of focus (DOF) margin, the energy latitude (EL) margin and to form an excellent profile without excessively increasing the exposure dose.

In order to form a desired pattern using the photosensitive resin composition mentioned above, the following process is used.

A bare silicon wafer, or a silicon wafer having a silicon oxide film, a silicon nitride film, or a lower film quality of a silicon oxynitride film formed on a top surface thereof, is prepared, and the silicon wafer is hexamethyl disilazane (HMDS). Treatment or by forming a bottom anti-reflective coating (BARC). Thereafter, the photosensitive resin composition is coated on the silicon wafer to a thickness of about 3800 kPa to about 4000 kPa to form a photosensitive resin film.

The silicon wafer on which the photosensitive resin film was formed was soft-baked (SB, pre-baking) for about 60 seconds to about 90 seconds in a temperature range of about 90 ° C to about 120 ° C. The solvent is removed and exposed using ArF or extreme UV (EUV), E-beam, and the like. Subsequently, a post-exposure baking, for about 60 seconds to about 90 seconds in a temperature range of about 90 ° C to about 120 ° C, in order to cause the exposed wafer to undergo a chemical reaction in the exposure region of the photosensitive resin film. PEB).

Thereafter, the photosensitive resin film is developed with an aqueous alkali solution which is a developer. At this time, the exposed portion exhibits a very large solubility characteristic with respect to the developer, so that it is well dissolved and removed during development. Tetramethylammonium hydroxide (TMAH) aqueous solution may be used as the developer. When the exposure source used is an ArF excimer laser, a line and space pattern (L / S) of about 80 nm to about 300 nm at a dose of about 20 mJ / cm 2 to about 50 mJ / cm 2 Can be formed.

The lower film quality such as a silicon oxide film is etched by using a photosensitive resin pattern thus obtained as a mask and using a plasma of a specific etching gas, for example, a halogen gas or a fluorocarbon gas. Subsequently, a stripper may be used to remove the photosensitive resin pattern remaining on the wafer to form a desired silicon oxide film pattern.

Hereinafter, the present invention will be described in more detail with reference to Examples, but these Examples are for illustrative purposes only and are not to be construed as limiting the present invention.

((Meth) acrylate monomer synthesis)

Synthesis Example 1 THP2M Synthesis

Scheme 1

7.9 ml (0.0931 mol) of methacrylic acid (TCI) and 1.01 g (0.004 mol) of pyridinium para-toluene sulfonate (PPTS) (Aldrich) were added to 80 ml of dichloromethane. , DCM) (TCI Co., Ltd.), 3,4-dihydro-2H-pyran (3,4-dihydro-2H-pyran, DHP) (TCI Co.) 14.7ml (0.162mol) was added to room temperature 1 Stir for days. After completion of the reaction, the reaction product was diluted with 250 ml of dichloromethane, washed once with 250 ml of brine and three times with 250 ml of deionized water (DIW). The organic layer was taken up, dried over Na ₂ SO ₄ , and the solvent was removed to obtain 13.14 g of tetrahydro-2H-pyran-2-yl methacrylate (THP2M). Yield 83%.

Synthesis Example 2: THFM Synthesis

Scheme 2

2,3-dihydrofuran (2) in place of 14.7 ml (0.162 mol) of 3,4-dihydro-2H-pyran (DHP) (TCI) in Synthesis Example 1 Tetrahydrofuran-2-yl methacrylate (tetrahydrofuran-2-yl methacrylate) in the same manner as in Synthesis Example 1, except that 12.239 ml (0.162 mol) of 3-dihydrofuran, DHF) (TCI) was used. THFM) 10.46 g was obtained. Yield 72%.

Synthesis Example 3 THP4M Synthesis

Scheme 3

5.0 g (0.049 mol) of tetrahydro-4-pyranol (THP) (Aldrich) and 8.2 ml (0.0587 mol) of triethylamine (Et ₃ N) (Aldrich) at 0 ° C In 50ml of dichloromethane (DCM) (TCI Co., Ltd.) at a temperature of 5.3ml (0.0539mol) of methacryloyl chloride (Aldrich Co.) was added and stirred at room temperature for 1 day. After the completion of the reaction, the reaction product was quenched with NaHCO ₃ , diluted with 100 ml of ethyl acetate, washed three times with 100 ml of saturated NaHCO ₃ , once with 150 ml of brine, and twice with 150 ml of deionized water (DIW). It was. The organic layer was taken up and dried over Na ₂ SO ₄ , purified through column chromatography (1: 19 = EA: Hex), and then the solvent was removed to remove tetrahydro-2H-pyran-4-yl meta. 4.64 g of methacrylate (tetrahydro-2H-pyran-4-yl methacrylate, THP4M) was obtained. The yield was 55.7%.

Synthesis Example 4 PP4M Synthesis

Scheme 4

9.51 g (0.091 mol) of methacryloyl chloride (Aldrich) was added to 60 ml of ethanol, and 10 ml of 3N hydrochloric acid was added thereto and refluxed under stirring for 4 hours. Then 200 ml of dioxane (in-situ) was added, t-butyl-4-hydroxypiperidine-1-carboxylate (tert-butyl-4-hydroxypiperidine-1-carboxylate) (TCI company ) 21.98 g (0.109 mol) was added thereto, followed by 8.62 g pyridine (0.109 mol), followed by stirring at room temperature for 2 hours. After drying the solvent, it is dissolved in 500ml of chloroform and purified by washing three times with 0.1N hydrochloric acid (300ml). After taking the organic layer, and dried over Na ₂ SO ₄ , to purify the compound through column chromatography (1: 5 = EA: Hex), the solvent was removed, piperidin-4-yl methacrylate (piperidin -4-yl methacrylate, PP4M) was obtained 5.08 g. Yield 33%.

((Meth) acrylate polymer polymerization)

Example 1

Cyclohexyl methacrylate (CHMA) (TCI), γ-butyrolactonyl methacrylate (GBLMA) (aldrich) and t-butyl methacrylate (tert-butylmethacrylate, t) -BMA) (TCI Co., Ltd.) were each mixed in a molar ratio of 3: 3: 4, and azobisisobutyronitrile (AIBN) (Cafe Gold Co., Ltd.) was used as an initiator. 5 mole% together of the total amount of CHMA, GBLMA 'and t-BMA).

They are dissolved in methyl ethyl ketone (MEK), which is twice the total weight of the monomer, and added dropwise to MEK, which is 1 times the total weight of the monomer previously heated to 80 ° C., for 3 hours. . After completion of dropping, polymerization was carried out at the same temperature for 3 hours. Then, it was precipitated using n-hexane (n-hexane) and dried under vacuum to obtain a powdery (meth) acrylate polymer.

Example 2

A (meth) acrylate polymer was obtained in the same manner as in Example 1 except that CHMA, GBLMA ', and t-BMA were each used at a molar ratio of 3: 4: 3.

Example 3

A (meth) acrylate polymer was obtained in the same manner as in Example 1, except that CHMA, GBLMA ', and t-BMA were used in a molar ratio of 2: 5: 3, respectively.

Example 4

Except for using CHMA in Example 1 except that tetrahydro-2H-pyran-2-yl methacrylate (THP2M) prepared in Synthesis Example 1 was used, A (meth) acrylate polymer was obtained in the same manner as in Example 1.

Example 5

Except for using CHMA in Example 1 except that tetrahydrofuran-2-yl methacrylate (tetrahydrofuran-2-yl methacrylate, THFM) prepared in the same manner as in Example 1 ( A meta) acrylate type polymer was obtained.

Example 6

Except for using CHMA in Example 1 except that tetrahydro-2H-pyran-4-yl methacrylate prepared in Synthesis Example 3 (tetrahydro-2H-pyran-4-yl methacrylate, THP4M) A (meth) acrylate polymer was obtained in the same manner as in Example 1.

Example 7

A (meth) acrylate polymer was obtained in the same manner as in Example 1, except that tetrahydrofurfuryl methacrylate (THFFMA) (TCI, Inc.) was used in place of CHMA.

Example 8

Except for using CHMA in Example 1 except that piperidin-4-yl methacrylate (PP4M) prepared in Synthesis Example 4 in the same manner as in Example 1 ( A meta) acrylate type polymer was obtained.

Comparative Example 1

A (meth) acrylate polymer was obtained in the same manner as in Example 1, except that hydroxyadamantyl methacrylate (HAMA) (TCI, Inc.) was used in place of CHMA.

Comparative Example 2

Example 1 and 1 except that 2-methyladamantan-2-yl methacrylate (MAMA) (TCI, Inc.) was used in place of t-BMA in Comparative Example 1 In the same manner, a (meth) acrylate polymer was obtained.

Comparative Example 3

(Meta) acrylate-based polymer was obtained in the same manner as in Example 1 except that HAMA, GBLMA ', and MAMA were used in a molar ratio of 3: 4: 3, respectively.

Comparative Example 4

Example 1 and 2 except that 2-ethyladamantan-2-yl methacrylate (EAMA) (TCI, Inc.) was used instead of t-BMA in Comparative Example 1 In the same manner, a (meth) acrylate polymer was obtained.

Comparative Example 5

(Meta) acrylate-based polymer was obtained in the same manner as in Example 1 except that HAMA, GBLMA ', and EAMA were each used in a molar ratio of 3: 4: 3.

Comparative Example 6

Example 1 and 2 except that 2-methyladamantan-2-yl methacrylate (MAMA) (TCI Co., Ltd.) was used in place of t-BMA. In the same manner, a (meth) acrylate polymer was obtained.

(Photosensitive resin composition production)

Each (meth) acrylate polymer prepared in Examples 1 to 8 and Comparative Examples 1 to 6, 6 parts by weight of triphenylsulfonium perfluor based on 100 parts by weight of the (meth) acrylate polymer as a photoacid generator Triphenylsulfonium perfluorobutylsulfonate (SP-104 from SMC), and 25 parts by weight of Nt-butoxycarbonyl-4-hydroxypiperidine (Nt-butoxycarbonyl) based on 100 parts by weight of the photoacid generator as a quencher -4-hydroxypiperidine), 　 It was dissolved in a propyleneglycol monomethylether acetate (PGMEA) solvent to 10% by weight to prepare each photosensitive resin composition.

Evaluation 1: Pattern Lifting Measurement

A 8 "bare silicon wafer is baked at 150 ° C./60 s with hexamethyl disilazane (HMDS), and the photosensitive resin compositions according to Examples 1 to 8 and Comparative Examples 1 to 6, respectively, are baked. After spin coating to a thickness of 4,000 kPa, soft baking (SB) was performed at 110 ° C. for 60 seconds.

250nm 1 phase shift mask (PSM) using NSR-S308F (LENS NA: 0.85, ILLUMINATION NA: 0.68, Conv. (Large), sigma: 0.80), an NIKON ArF scanner After exposing the: 1 line and space (L / S) pattern, post exposure baking (PEB) was performed at 110 ° C. for 60 seconds. It was developed by puddling method for 60 seconds with 2.38% of tetramethyl ammonium hydroxide (TMAH) developer.

The minimum pattern size at which pattern lifting occurs even at an optimum energy (E _op ) and an optimum depth of focus was measured, and the results are shown in Table 1 below.

Evaluation 2: measuring the development rate (DR)

Each of the photosensitive resin compositions according to Examples 1 to 8 and Comparative Examples 1 to 6 was spin coated to a thickness of 4,000 kPa on an 8 "bare silicon wafer, and then baked at 110 ° C for 60 seconds, which was then applied for about 1 minute. The thickness of the wafer coated with the photosensitive resin composition was measured by using a thickness gauge (K-MAC Co., Ltd.) The wafer coated with the photosensitive resin composition was then 2.38% by weight of tetramethylammonium hydroxide. It was developed by inserting it into RDA-760 (Litho Tech Japan Co., Ltd.) containing (tetramethyl ammonium hydroxide, TMAH) 웨이퍼 For each wafer that has been measured, the difference between the initial thickness and the later thickness was measured. The developing speed was calculated and shown in Table 1 below.

Evaluation 3: Implant Resistance Measurement

Each of the photosensitive resin compositions of Examples 1 to 8 and Comparative Examples 1 to 5 was applied to an 8 "bare silicon wafer and baked at 110 ° C. for 60 seconds. The resultant was cooled to room temperature for about 1 minute again, respectively, 300 Å and 500 Å A wafer coated with a photosensitive resin composition having a thickness of 1,000 Å, 2,000 Å, 3,000 Å and 4,000. Was obtained using Varian's VIISta80-HP equipment to convert boron monofluoride (BF) into impact energy: 8 keV, 5 × 10 ¹³ boron / cm ² doses were implanted, and the remaining photosensitive resin composition was then O ₂ ashed using PSK DAS2000 equipment and thoroughly cleaned with Hitachi NXWET. Subsequently, the measurement of boron (B) permeated to the wafer was carried out using secondary ion mass spectrometry (SIMS) using an IMS-6f Magnetic Sector device from CAMECA, O ₂ ⁺ Gun, impact energy: 7.5 keV, 300nA 　 Measured by current.

If the photosensitive resin composition had a high intensity of boron (B) measured in the wafer after the implant at a thickness lower than the high thickness, boron penetrated the wafer through the photosensitive resin film during the implant. Therefore, as the minimum thickness of the boron in the wafer after the ion implantation is not different, the implant resistance was evaluated as good. The minimum thickness is shown in Table 1 below.

Table 1

	(Meth) acrylate-based polymer composition ratio	Weight average molecular weight (g / mol)	Dispersion	E op (mJ)	SIMS (Å)	Development speed (DR) (nm / s)	lifting pattern minimum pattern size (nm)
Example 1	CHMA: GBLMA: t-BMA (3: 3: 4)	8,100	1.6	24	300	82.4	130
Example 2	CHMA: GBLMA: t-BMA (3: 4: 3)	7,700	1.6	23	300	91.2	130
Example 3	CHMA: GBLMA: t-BMA (2: 5: 3)	8,300	1.6	24	300	93.2	130
Example 4	THP2M: GBLMA: t-BMA (3: 3: 4)	8,800	1.6	23	500	85.5	130
Example 5	THFM: GBLMA: t-BMA (3: 3: 4)	8,700	1.6	22	500	87.7	130
Example 6	THP4M: GBLMA: t-BMA (3: 3: 4)	8,100	1.6	23	500	83.1	130
Example 7	THFFMA: GBLMA: t-BMA (3: 3: 4)	7,900	1.8	28	500	96.0	130
Example 8	PP4M: GBLMA: t-BMA (3: 3: 4)	8,400	1.7	35	500	74.5	130
Comparative Example 1	HAMA: GBLMA: t-BMA (3: 3: 4)	8,500	1.6	25	500	42.3	150
Comparative Example 2	HAMA: GBLMA: MAMA (3: 3: 4)	8,800	1.6	21	500	1.3	200
Comparative Example 3	HAMA: GBLMA: MAMA (3: 4: 3)	8,600	1.6	20	500	2.1	200
Comparative Example 4	HAMA: GBLMA: EAMA (3: 3: 4)	8,800	1.6	18	500	3.4	220
Comparative Example 5	HAMA: GBLMA: EAMA (3: 4: 3)	8,400	1.6	18	500	2.3	220
Comparative Example 6	CHMA: GBLMA: MAMA (3: 3: 4)	8,900	1.6	24	500	22.5	200

Evaluation 4: Scum Evaluation

The 8 "bare silicon wafer was spin-coated each of the photosensitive resin compositions of Examples 1-8 and Comparative Examples 1-6 with the thickness of 5,000 kPa, and soft-baked at 110 degreeC for 60 second.

The coated wafer was subjected to a phase shift mask (PSM) using an NSR-S308F (LENS NA: 0.85, ILLUMINATION NA: 0.68, Conv. (Large), sigma: 0.80), an NIKON ArF scanner. A 150 nm trench pattern was exposed and then 110 ° C./60 s post exposure baking (PEB). It was developed by puddling method for 60 seconds with 2.38% of tetramethyl ammonium hydroxide (TMAH) developer.

CD-SEM was used to observe the scum at the end of the trench pattern. The edge of the pattern was developed, but the scum performance was evaluated to the extent that no scum remained inside. That is, despite the evaluation of the thick film thickness, it was determined that less scum occurred as the inside of the fine trench pattern melted well.

1A is a CD-SEM photograph of a 150 nm pattern (optimal energy (E _op )) obtained using the photosensitive resin composition according to Example 1, and FIG. 1B is 150 nm obtained using the photosensitive resin composition according to Example 1 CD-SEM photograph of the pattern (2 mJ / cm ² less than the optimal energy (E _op )), FIG. 1C is 4 nm than the 150 nm pattern (optimal energy (E _op ) obtained using the photosensitive resin composition according to Example 1 mJ / cm ² less) CD-SEM photo.

FIG. 2A is a CD-SEM photograph of a 150 nm pattern (optimal energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 1, and FIG. 2B is 150 nm obtained using the photosensitive resin composition according to Comparative Example 1 CD-SEM photograph of the pattern (2 mJ / cm ² less than the optimal energy (E _op )), Figure 2c is a 150 nm pattern obtained by using the photosensitive resin composition according to Comparative Example 1 (4 than the optimal energy (E _op ) mJ / cm ² less) CD-SEM photo.

3A is a CD-SEM photograph of a 150 nm pattern (optimum energy (E _op )) obtained using the photosensitive resin composition according to Comparative Example 2, and FIG. 3B is 150 nm obtained using the photosensitive resin composition according to Comparative Example 2. CD-SEM photograph of the pattern (2 mJ / cm ² less than the optimal energy (E _op )), Figure 3c is 4 nm than the 150 nm pattern (optimal energy (E _op ) obtained using the photosensitive resin composition according to Comparative Example 2 mJ / cm ² less) CD-SEM photo.

Referring to Figure 1a, the pattern of Example 1 using the (meth) acrylate-based polymer according to one embodiment, the phenomenon is clear to the inside, the pattern is formed in a straight line can be seen not only excellent scum performance but also patternability have. On the other hand, referring to Figures 2a and 3a, it can be seen that the patterns of Comparative Examples 1 and 2 are not well formed due to scum.

Referring to FIGS. 1B and 1C, 2B and 2C, and 3B and 3C, in order to more clearly understand scum performance, the exposure is performed by 2 mJ / cm ² and 4 mJ / cm ² less than the optimum energy (E _op ), respectively. Compared. In this case, it can be seen that the pattern of Example 1 is superior to the scum and the pattern form than the patterns of Comparative Examples 1 and 2.

In addition, Comparative Examples 1 and 2 have a maximum trench pattern width of 130 nm, but Example 1 has a depth of focus (DOF) margin and exposure latitude (EL) of up to 110 nm. Margin and the like can be excellently implemented.

4 shows the depth of focus (DOF) margin at the 150 nm pattern (optimum energy (E _op ): 36 mJ / cm ² ) obtained using the photosensitive resin composition according to Example 1 at the center and the edge of the pattern. CD-SEM photo showing.

The depth of focus margin refers to the allowable focus range of the resultant pattern even when the focus at the optimal energy E _op is out of the best focus. The acceptable focus range typically represents ± 10% of the CD size.

Referring to FIG. 4, the best condition is -0.05 um, and the depth of focus margin is 0.25 um (-0.15 um to 0.1 um). In addition, both the center and the edge of the pattern are developed cleanly, so it can be confirmed that the scum surface is clean.

FIG. 5 shows the exposure latitude (EL) margin of the 150 nm pattern (optimum energy (E _op ): 36 mJ / cm ² ) obtained using the photosensitive resin composition according to Example 1 with respect to the pattern center and edges. FIG. CD-SEM picture.

The exposure allowance margin indicates an allowable exposure range of the resultant pattern even when the exposure energy is out of the optimum energy E _op at the best focus, and the allowable energy range is optimal energy. Divided by (E _op ). The acceptable exposure range typically represents ± 10% of the CD size.

Referring to FIG. 5, the exposure allowance margin is 22% (32 mJ to 8 mJ from 40 mJ). In addition, since both the center and the edge of the pattern are developed cleanly from the under dose to the over dose, it can be confirmed that the scum surface is also clean.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

Claims (13)

1. (Meth) acrylate-based polymer comprising a repeating unit represented by the formula (1) to (3).

   [Formula 1]

   

   (In Formula 1,

   R ¹ contains hydrogen or a methyl group,

   R ¹⁰ comprises a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 heterocycloalkyl group,

   n is an integer of 0 to 3)

   [Formula 2]

   

   (In Formula 2,

   R ² contains hydrogen or a methyl group,

   R ²⁰ includes an ester group and includes a substituted or unsubstituted C3 to C20 cycloalkyl group.)

   [Formula 3]

   

   (In Chemical Formula 3,

   R ³ contains hydrogen or a methyl group,

   R ³⁰ includes t-butyl group, triethylcarbyl group, 1-methyl cyclohexyl group, 1-ethylcyclopentyl group, t-amyl group or acetal group.)
2. The method of claim 1,

   The repeating unit represented by Formula 1 is a (meth) acrylate-based polymer containing any one of the repeating units represented by the following formula 4 to 23.

   [Formula 4]

   

   [Formula 5]

   

   [Formula 6]

   

   [Formula 7]

   

   [Formula 8]

   

   [Formula 9]

   

   [Formula 10]

   

   [Formula 11]

   

   [Formula 12]

   

   [Formula 13]

   

   [Formula 14]

   

   [Formula 15]

   

   [Formula 16]

   

   [Formula 17]

   

   [Formula 18]

   

   [Formula 19]

   

   [Formula 20]

   

   [Formula 21]

   

   [Formula 22]

   

   [Formula 23]

   
3. The method of claim 1,

   In the definition of R ¹⁰ in Formula 1, the heterocycloalkyl group is a (meth) acrylate-based polymer containing a hetero atom of oxygen (O) or nitrogen (N).
4. The method of claim 1,

   R ²⁰ in Formula 2 is a gamma-butyrolactonyl group, a valerolactonyl group, a 1,3-cyclohexanecarbolactonyl group, 2,6 Norbornanecarbolacton-5-yl (2,6-norbornanecarbolacton-5-yl) or 7-oxa-2,6-norbornanecarbolactone-5-yl (7-oxa-2,6-norbornanecarbolacton A (meth) acrylate type polymer containing a -5-yl) group.
5. The method of claim 1,

   The (meth) acrylate polymer is a (meth) acrylate polymer having a weight average molecular weight of 3,000 to 20,000 g / mol.
6. The method of claim 1,

   The (meth) acrylate polymer is a (meth) acrylate polymer having a dispersity of 1.3 to 2.5.
7. The method of claim 1,

   The (meth) acrylate-based polymer,

   10 to 40 mol% of repeating units represented by Formula 1;

   20 to 60 mol% of repeating units represented by Formula 2; And

   20 to 50 mol% of repeating units represented by Formula 3

   A (meth) acrylate-based polymer comprising a.
8. The (meth) acrylate type polymer of any one of Claims 1-7;

   Photo acid generator (PAG); And

   menstruum

   Photosensitive resin composition comprising a.
9. The method of claim 8,

   The (meth) acrylate-based polymer is 5 to 15% by weight based on the total amount of the photosensitive resin composition.
10. The method of claim 8,

    The photoacid generator is triarylsulfonium perfluoroalkylsulfonate, triarylsulfonium triflate, diaryliononium triflate, triarylsulfonium nonaplate, diaryliononium nonaplate, succinimidyl tri A photosensitive resin composition comprising a plate, 2,6-dinitrobenzyl sulfonate or a combination thereof.
11. The method of claim 8,

    The photoacid generator is 1 to 15 parts by weight based on 100 parts by weight of the (meth) acrylate-based polymer photosensitive resin composition.
12. The method of claim 8,

    The photosensitive resin composition further comprises 0.1 to 5 parts by weight of the organic amine based on 100 parts by weight of the (meth) acrylate-based polymer.
13. The method of claim 12,

    Wherein the organic amine comprises triethylamine, triisobutylamine, trioctylamine, triisodecylamine, triethanolamine, hydroxypiperidine, or a combination thereof.

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