Photoresist composition

Abstract

The present invention relates to a chemically amplified photoresist composition including an alkali-soluble resin including a (meth)acrylate-based resin containing a (meth)acrylate-based repeating unit in which a heterocyclic compound is substituted via a divalent functional group containing an alkylene sulfide having 1 to 20 carbon atoms.

Claims

1. A chemically amplified photoresist composition, comprising an alkali-soluble resin including a (meth)acrylate-based resin containing a (meth)acrylate-based repeating unit, wherein the (meth)acrylate-based repeating unit includes a heterocyclic compound that is substituted via a divalent functional group containing an alkylene sulfide having 1 to 20 carbon atoms, wherein the heterocyclic compound is at least one selected from the group consisting of a triazole-based compound, an imidazole-based compound, a thiadiazole-based compound, a triazine-based compound, and a benzimidazole-based compound, and wherein the (meth)acrylate-based repeating unit includes a repeating unit represented by Chemical Formula A below: ##STR00014## wherein, in Chemical Formula A, Ra is hydrogen or methyl, Rb and Rc are each a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, and X is the heterocyclic compound.

2. The chemically amplified photoresist composition of claim 1, wherein the (meth)acrylate-based resin contains 1 to 50% by weight of the (meth)acrylate-based repeating unit.

3. The chemically amplified photoresist composition of claim 1, wherein the (meth)acrylate-based resin further contains a repeating unit derived from at least one compound selected from the group consisting of compounds represented by Chemical Formulae 1 to 8 below: ##STR00015## ##STR00016## wherein, in Chemical Formulae 1 to 8, R.sub.1 is hydrogen, a halogen, or an aliphatic group having 1 to 10 carbon atoms; and n.sub.1 and n.sub.2 are integers, wherein 1≤n.sub.1≤18 and 1≤n.sub.2≤18.

4. The chemically amplified photoresist composition of claim 1, wherein the heterocyclic compound is derived from one selected from compounds represented by Chemical Formulae 9 to 14 below: ##STR00017## wherein, in Chemical Formulae 9 to 14, R.sub.2 to R.sub.10 are each independently hydrogen, a halogen, a thiol (SH), an amine (NH.sub.2), a hydroxy (OH), an alkylene having 1 to 20 carbon atoms, or an alkoxy group having 1 to 20 carbon atoms, R.sub.11 is a functional group containing a thiol (SH) or a functional group containing an alkylene thiol having 1 to 20 carbon atoms, and n.sub.3 and n.sub.4 are integers, wherein 1≤n.sub.3≤2 and 1≤n.sub.4≤4.

5. The chemically amplified photoresist composition of claim 1, wherein the alkylene sulfide having 1 to 20 carbon atoms is formed by a thiol-ene click reaction of a thiol group in the heterocyclic compound with a double bond at a terminal of the (meth)acrylate-based repeating unit.

6. The chemically amplified photoresist composition of claim 1, wherein the alkali-soluble resin further includes at least one selected from the group consisting of a (meth)acrylate-based resin different from the (meth)acrylate-based resin containing a (meth)acrylate-based repeating unit in which a heterocyclic compound is substituted via a divalent functional group containing an alkylene sulfide having 1 to 20 carbon atoms; a novolac-based resin; and a polyhydroxystyrene-based resin.

7. The chemically amplified photoresist composition of claim 1, further comprising at least one selected from a photoacid generator and a photoinitiator.

8. A method for preparing a photoresist pattern, the method comprises: a lamination step of laminating a thick film photoresist layer comprising the chemically amplified photoresist composition of claim 1 on a support; an exposure step of irradiating the thick film photoresist layer with radiation including electromagnetic waves or particle beams; and a development step of developing the thick film photoresist layer after exposure to obtain a thick film resist pattern.

9. The chemically amplified photoresist composition of claim 7, further comprising at least one selected from an acid diffusion control agent and a dissolution inhibitor.

10. A photoresist pattern prepared by the method of claim 8.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 illustrates the process for forming bumps using the photoresist composition of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(2) The present invention can make various modifications and take various forms, and thus specific embodiments are illustrated and described in detail below.

(3) It should be understood, however, that the present invention is not intended to be limited to any particular disclosure form, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

(4) Hereinafter, the action and effect of the present invention will be described by way of specific examples.

(5) However, these examples are given for illustrative purposes only, and the scope of the invention is not intended to be limited by these examples.

Example 1: Preparation of Chemically Amplified Photoresist Composition Including Alkali Soluble Resin in which Heterocyclic Compound is Substituted Via Alkylene Sulfide Having 1 to 20 Carbon Atoms

(6) Tert-butyl methacrylate, methacrylic acid, 2-(allyloxy)ethyl methacrylate, dicyclopentanyl methacrylate (FA-513M), 1-dodecanethiol, and PGMEA (solvent) were added to a reactor in an amount of 95.58 g, 28.94 g, 85.86 g, 37.05 g, 2.19 g, and 320.09 g, respectively, to prepare a uniform solution.

(7) The internal temperature of the solution was set to 65° C. under a nitrogen atmosphere, and then 1.62 g of AIBN was dissolved in 14.58 g of PGMEA and added to the solution.

(8) After reacting for 18 hours, the polymerization reaction was terminated to obtain a resin represented by Chemical Formula 15 below (Mw: 25.2 k).

(9) 137.8 g of AIBN and 10.1 g of a corrosion inhibitor 1H-1,2,4-triazole-3-thiol represented by Chemical Formula 16 below were further added to the reactor.

(10) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 17 below, wherein the acrylic resin and the corrosion inhibitor were bonded via a functional group containing an alkylene sulfide.

(11) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(12) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(13) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 17 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(14) ##STR00005##

Example 2

(15) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 10.0 g of a corrosion inhibitor 4H-imidazole-2-thiol represented by Chemical Formula 18 were further added thereto.

(16) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 19 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide.

(17) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(18) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(19) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 19 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor (quencher), and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(20) ##STR00006##

Example 3

(21) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 11.6 g of a corrosion inhibitor 1-methyl-4,5-dihydro-1H-imidazole-2-thiol represented by Chemical Formula 20 were further added thereto.

(22) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 21 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide.

(23) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(24) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(25) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 21 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(26) ##STR00007##

Example 4

(27) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 16.1 g of a corrosion inhibitor 4,6-dimercapto-1,3,5-triazin-2-ol represented by Chemical Formula 22 were further added thereto.

(28) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 23 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide. When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(29) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(30) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 23 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(31) ##STR00008##

Example 5

(32) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 14.5 g of a corrosion inhibitor 6-mercapto-1,3,5-triazine-2,4-diol represented by Chemical Formula 24 were further added thereto.

(33) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 25 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide.

(34) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(35) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(36) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 25 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(37) ##STR00009##

Example 6

(38) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 11.8 g of a corrosion inhibitor 1,3,4-thiadiazole-2-thiol represented by Chemical Formula 26 were further added thereto.

(39) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 27 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide.

(40) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(41) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(42) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 27 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(43) ##STR00010##

Example 7

(44) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 14.6 g of a corrosion inhibitor 5-diazenyl-1,3,4-thiadiazole-2-thiol represented by Chemical Formula 28 were further added thereto.

(45) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 29 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide.

(46) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(47) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(48) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 29 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(49) ##STR00011##

Example 8

(50) A resin represented by Chemical Formula 15 was obtained in the same manner as in Example 1. Then, the resin was placed into a reactor, and 137.8 g of AIBN and 15.0 g of a corrosion inhibitor 1,3,4-thiadiazole-2,5-dithiol represented by Chemical Formula 30 were further added thereto.

(51) The thiol-ene click reaction was carried out at 65° C., which was the same as the polymerization temperature, for 3 hours to prepare a compound having the structure of Chemical Formula 31 below, wherein the acrylic resin and the corrosion inhibitor are bonded via the functional group containing an alkylene sulfide.

(52) When the reaction was completed, the temperature was lowered to room temperature, and the resultant was diluted with IPA and PGMEA and poured into water to remove a precipitate.

(53) The polymer obtained by filtration was poured again into a mixture solvent of IPA and PGMEA, precipitated, filtered, and then dried in an oven at 40° C. for a day.

(54) 40 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, 4 g of the compound represented by Chemical Formula 31 below, which was subjected to a thiol-ene click reaction, and 6 g of poly(4-vinylphenol) (Mw: 25.1 k) were mixed. In addition, 3 g of the photoacid generator, 0.5 g of the acid diffusion inhibitor, and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(55) ##STR00012##

Comparative Example 1

(56) 44 g of the acrylic resin (Mw: 25.1 k) represented by Chemical Formula 32 below, as an alkali-soluble resin, 6 g of poly(4-vinylphenol) (Mw: 25.1 k), and 3 g of trifluoromethylsulfonyloxy-1,8-naphthalimide represented by Chemical Formula 33 below, as a photoacid generator, were mixed. Then 0.5 g of the acid diffusion inhibitor and 50 g of PGMEA as a solvent were mixed thereto as additional additives, and the mixture was stirred at room temperature to prepare a uniform solution, thereby obtaining a chemically amplified photoresist composition.

(57) ##STR00013##

Experimental Examples

(58) Semiconductor elements were patterned in the following manner using each of photoresist compositions of the examples and the comparative example.

(59) The photoresist composition was spin-coated on a 4-inch Si wafer coated with copper (Cu) in a thickness of about 2000 Å, and then dried at 120° C. for 4 minutes to form a photoresist layer having a thickness of about 50 μm.

(60) The wafer was exposed to light using an i-line stepper (equipped with a photomask on which hole patterns in the size of about 10, 20, 30, 40, and 50 μm are formed).

(61) The exposed wafer was dried at 90° C. for 3 minutes, and then developed for 240 seconds using a developing solution (aqueous solution of about 2.38 wt % tetramethylammonium hydroxide).

(62) After patterning, the physical properties of the photoresist compositions were evaluated in the following manner.

(63) (1) Sensitivity (Amount of Exposure, mJ/cm.sup.2)

(64) The photoresist compositions prepared in Examples 1 to 8 and Comparative Example 1 were spin-coated on a substrate and dried on a hot plate at 120° C. for 4 minutes, then exposed to light using a step mask, and additionally dried on a hot plate at 90° C. for 3 minutes and developed in an aqueous solution of tetramethylammonium hydroxide (TMAH).

(65) The amount of exposure with the same CD size of the step mask pattern and the photoresist (PR) pattern was evaluated as sensitivity.

(66) (2) Occurrence of Footing at the Bottom of Pattern

(67) The photoresist compositions prepared in Examples 1 to 8 and Comparative Example 1 were spin-coated on a substrate and dried on a hot plate at 120° C. for 4 minutes, then exposed to light using a step mask, and additionally dried on a hot plate at 100° C. for 2 minutes and developed in an aqueous solution of tetramethylammonium hydroxide (TMAH).

(68) The value at which the hole diameter at the bottom was reduced from the hole diameter at the top of the thick resist pattern was measured as the footing length.

(69) The footing characteristics of PR were evaluated based on the following criteria.

(70) ⊚: Footing length of greater than 0 nm and less than or equal to 200 nm

(71) ∘: Footing length of greater than 200 nm and less than or equal to 500 nm

(72) Δ: Footing length of greater than 500 nm and less than or equal to 1 μm

(73) X: Footing length of greater than 1 μm

(74) (3) Evaluation on Occurrence of Scum (Presence or Absence of Residue)

(75) A thick film resist pattern was prepared in the same manner as for the occurrence of footing at the bottom of the pattern, and the presence or absence of scum on the development portion was observed and used as the index for evaluating the developing property. The developing property was evaluated based on the following criteria.

(76) ⊚: No occurrence of scum

(77) Δ: Occurrence of some scum around pattern

(78) X: Occurrence of scum on the entire development portion

(79) (4) Resistance to Plating Solution

(80) The photoresist compositions prepared in Examples 1 to 8 and Comparative Example 1 were coated onto a substrate using a spin coater, and then a resist film formed by processes such as prebake and post-bake was immersed in a Cu plating solution at room temperature for 24 hours to examine any changes in the thickness of the resist film.

(81) The rate of change in thickness was evaluated based on the following criteria.

(82) ⊚: Rate of change in thickness less than 1%

(83) ∘: Rate of change in thickness greater than 1% and less than or equal to 3%

(84) Δ: Rate of change in thickness greater than 3% and less than or equal to 10%

(85) X: Rate of change in thickness greater than 10%

(86) TABLE-US-00001 TABLE 1 Resistance Sensitivity Occurrence to plating (mJ/cm.sup.2) Footing of scum solution Example 1 350 ◯ ⊚ ◯ Example 2 310 ◯ ⊚ ◯ Example 3 340 ◯ ⊚ ◯ Example 4 280 ◯ ⊚ ◯ Example 5 270 ⊚ ⊚ ⊚ Example 6 290 ⊚ ⊚ ⊚ Example 7 380 ◯ ⊚ ⊚ Example 8 390 ◯ ⊚ ⊚ Comparative 550 X X X Example 1

(87) From the results shown in Table 1, it can be confirmed that the photoresist compositions of Examples 1 to 8 of the present invention which included the (meth)acrylate-based resin containing the (meth)acrylate-based repeating unit in which a specific heterocyclic compound is substituted via a divalent functional group containing an alkylene sulfide having 1 to 20 carbon atoms, as a part of the alkali soluble resin, exhibited excellent sensitivity, had no occurrence of footing and scum, and also showed excellent resistant to the plating solution as the leaching phenomenon was suppressed.