Positive-working photoresist composition, pattern produced therefrom, and method for producing pattern

Abstract

The present invention provides a positive photoresist composition having excellent storage stability, sensitivity, developing properties, plating resistance, and heat resistance. More specifically, a specific dissolution inhibitor in the form of an oligomer having the same repeating unit structure as the resin contained in the photoresist composition is applied to said composition.

Claims

1. A positive photoresist composition comprising: a binder resin comprising a polymer resin having a first repeating unit and an acrylate-based resin having a second repeating unit, the polymer resin having an alkali-soluble functional group introduced into the first repeating unit; an oligomer compound having a functional group to which at least one protecting group is introduced; and a photoacid generator, wherein the protecting group is selected from the group of acetal, tert-butyloxycarbonyl, and t-butyl ester, wherein the oligomer compound comprises the same first repeating unit as in the polymer resin or the same second repeating unit as in the acrylate-based resin; and wherein a chain transfer agent represented by the following Chemical Formula 4 is introduced to the end of the repeating unit contained in the oligomer compound: ##STR00019## wherein, in Chemical Formula 4, R.sub.9, R.sub.10, and R.sub.11 are each independently hydrogen, a halogen, or an aliphatic group having 1 to 10 carbon atoms, and n.sub.6 is an integer, where 1≤n.sub.6≤20.

2. The positive photoresist composition according to claim 1, wherein the polymer resin is at least one selected from the group of acrylic resin, novolac resin, and polyhydroxystyrene resin.

3. The positive photoresist composition according to claim 1, wherein the alkali-soluble functional group is a hydroxyl group or a carboxylic acid group.

4. The positive photoresist composition according to claim 1, wherein the oligomer compound has a weight average molecular weight in the range of 1500 to 5000.

5. The positive photoresist composition according to claim 1, wherein the first or second repeating unit contained in the oligomer compound is at least one of the following Chemical Formulae 1, 2, and 3: ##STR00020## wherein, in Chemical Formula 1, R.sub.1 and R.sub.2 are hydrogen, a halogen, or an aliphatic group having 1 to 10 carbon atoms, n.sub.1 and n.sub.2 are each an integer, where 0≤n.sub.1≤3 and 0≤n.sub.2≤3, and a and b are each an integer, where 0<a≤80 and 20≤b≤50; ##STR00021## wherein, in Chemical Formula 2, R.sub.3 and R.sub.4 are hydrogen, a halogen, or an aliphatic group having 1 to 10 carbon atoms, n.sub.3 and n.sub.4 are each an integer, where 0≤n.sub.3≤4 and 0≤n.sub.4≤4, and c and d are each an integer, where 0<c≤80 and 20≤d≤50; and ##STR00022## wherein, in Chemical Formula 3, R.sub.5, R.sub.6, R.sub.7, and R.sub.8 are hydrogen, a halogen, or an aliphatic group having 1 to 10 carbon atoms, n.sub.5 is an integer, where 0≤n.sub.5≤5, and e, f, g, and h are each independently an integer of greater than 0 and 50 or less.

6. The positive photoresist composition according to claim 1, wherein the chain transfer agent is introduced in the range of 5% to 15% by weight, based on the total weight of the oligomer compound.

7. The positive photoresist composition according to claim 1, wherein the chain transfer agent is 3-mercapto propionic acid.

8. The positive photoresist composition according to claim 1, wherein the oligomer compound is represented by the following Chemical Formula 5: ##STR00023## wherein e, f, g, and h are each independently an integer of more than 0 and 50 or less.

9. A photoresist pattern produced from the positive photoresist composition according to claim 1.

10. A method for producing a thick film photoresist pattern, comprising: a lamination step of laminating a thick film photoresist layer comprising the 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 the thick film photoresist pattern.

11. A positive photoresist composition comprising: a binder resin comprising a polymer resin having a first repeating unit and an acrylate-based resin having a second repeating unit, the polymer resin having an alkali-soluble functional group introduced into the first repeating unit; an oligomer compound having a functional group to which at least one protecting group is introduced; and a photoacid generator, wherein the protecting group is selected from the group of acetal, tert-butyloxycarbonyl, and t-butyl ester, wherein the oligomer compound comprises the same first repeating unit as in the polymer resin or the same second repeating unit as in the acrylate-based resin, and wherein the oligomer compound is represented by the following Chemical Formula 5: ##STR00024## wherein e, f, g, and h are each independently an integer of more than 0 and 50 or less.

12. The positive photoresist composition according to claim 11, wherein the polymer resin is at least one selected from the group of acrylic resin, novolac resin, and polyhydroxystyrene resin.

13. The positive photoresist composition according to claim 11, wherein the alkali-soluble functional group is a hydroxyl group or a carboxylic acid group.

14. The positive photoresist composition according to claim 11, wherein the oligomer compound has a weight average molecular weight in the range of 1500 to 5000.

15. The positive photoresist composition according to claim 11, wherein a chain transfer agent represented by the following Chemical Formula 4 is introduced to the end of the repeating unit contained in the oligomer compound: ##STR00025## wherein, in Chemical Formula 4, R.sub.9, R.sub.10, and R.sub.11 are each independently hydrogen, a halogen, or an aliphatic group having 1 to 10 carbon atoms, and n.sub.6 is an integer, where 1≤n.sub.6≤20; and wherein the chain transfer agent is introduced in the range of 5% to 15% by weight, based on the total weight of the oligomer compound.

16. The positive photoresist composition according to claim 15, wherein the chain transfer agent is 3-mercapto propionic acid.

17. A photoresist pattern produced from the positive photoresist composition according to claim 11.

18. A method for producing a thick film photoresist pattern, comprising: a lamination step of laminating a thick film photoresist layer comprising the photoresist composition of claim 11 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 the thick film photoresist pattern.

Description

BRIEF DESCRIPTION OF DRAWING

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

DETAILED DESCRIPTION OF THE EMBODIMENTS

(2) Since the present invention may be modified in various forms and may have several embodiments, particular embodiments will now be illustrated and described in detail below. However, it will be understood that the present invention is not limited to the particular embodiments, and the invention includes all modifications, equivalents, and alternatives falling within the scope and sprit of the present invention.

(3) Hereinafter, the actions and effects of the present invention will be described by way of specific examples. However, these examples are given for illustrative purposes only, and they are not intended to limit the scope of the invention in any manner

(4) <Preparation of Photoresist Composition>

EXAMPLE 1

(5) 40 g of m,p-cresol novolac resin (Mw: 12,000, ADR 500 Å/s) represented by the following Chemical Formula 6 as a binder resin, 50 g of an acrylic resin (Mw: 65,000) represented by the following Chemical Formula 8; 10 g of an oligomer compound (Mw: 1500)of the following Chemical Formula 9 having a functional group protected with an acetal group as an oligomer compound, 3 g of N-(trifluoromethylsulfonyloxy)-1,8-naphthalimide as a photoacid generator, and 0.1 g of trihydroxyethylamine as a quencher were mixed, and then stirred at room temperature to prepare a homogeneous solution. Thereby, a positive photoresist composition was produced.

(6) ##STR00013##

EXAMPLE 2

(7) A positive photoresist composition was produced in the same manner as in Example 1, except that an oligomer compound (Mw: 2500) represented by Chemical Formula 11 was used as a dissolution inhibitor.

(8) ##STR00014##

EXAMPLE 3

(9) A positive photoresist composition was produced in the same manner as in Example 1, except that 10 g of m,p-cresol novolac resin (Mw: 12,000, ADR 500 Å/s) represented by the following Chemical Formula 6 as a binder resin, 30 g of an acetal-protected polyhydroxystyrene resin (Mw: 15,300, substitution ratio: 25%) represented by the following Chemical Formula 7, and 50 g of an acrylic resin (Mw: 65,000) represented by the following Chemical Formula 8 were used.

(10) ##STR00015##

EXAMPLE 4

(11) A positive photoresist composition was produced in the same manner as in Example 3, except that an oligomer compound (Mw: 2500, substitution ratio: 25%) represented by Chemical Formula 10 was used as a dissolution inhibitor.

(12) ##STR00016##

EXAMPLE 5

(13) A positive photoresist composition was produced in the same manner as in Example 4, except that 30 g of an acetal-protected polyhydroxystyrene resin (Mw: 15,300, substitution ratio: 25%) represented by the following Chemical Formula 7 and 60 g of the acrylic resin (Mw: 65,000) represented by the following Chemical Formula 8 were used as a binder resin.

(14) ##STR00017##

COMPARATIVE EXAMPLE 1

(15) A positive photoresist composition was produced in the same manner as in Example 1, except that 4,4-[1-[4-[1-(1,4-hydroxyphenyl)-1-methylethyl]phenyl]ethylidene] bisphenol (TPPA-EV) represented by the following Chemical Formula 12 was used as a dissolution inhibitor.

(16) ##STR00018##

(17) TABLE-US-00001 TABLE 1 Comparative Example 1 Example 2 Example 3 Example 4 Example 5 Example 1 Resin of Chemical 40 40 10 10 — 40 Formula 6 Resin of Chemical — — 30 30 30 — Formula 7 Resin of Chemical 50 50 50 50 60 50 Formula 8 Oligomer of Chemical 10 — 10 — — — Formula 9 Oligomer of Chemical — — — 10 10 — Formula 10 Oligomer of Chemical — 10 — — — — Formula 11 TPPA-EVE of Chemical — — — — — 10 Formula 12 Photoacid generator 3 3 3 3 3 3 PAG Quencher 0.1 0.1 0.1 0.1 0.1 0.1

(18) Evaluation

(19) (1) Sensitivity (Irradiation Dose)

(20) The photoresist compositions produced in Examples 1 to 5 and Comparative Example 1 were spin-coated onto a glass substrate, dried on a hot plate at 120° C. for 2 minutes, exposed using a step mask, and then further dried on the hot plate at 100° C. for 2 minutes. The resultant material was then developed in a TMAH (tetramethylammonium hydroxide) aqueous solution. The irradiation amount with the same CD size of the step mask pattern and the photoresist (PR) pattern was evaluated as the sensitivity. The results are shown in Table 2 below.

(21) (2) Developing Property

(22) The photoresist compositions prepared in Examples 1 to 5 and Comparative Example 1 were spin-coated on a glass substrate, dried on a hot plate at 120° C. for 2 minutes, exposed using a step mask, and then further dried on the hot plate at 100° C. for 2 minutes. The resultant material was then developed in a TMAH (tetramethylammonium hydroxide) aqueous solution. A value obtained by subtracting the hole diameter at the bottom from the hole diameter at the top of the thick resist pattern was measured as the length of footing and used as an index of the developing property. The developing property was measured based on the following criteria, and the results are shown in Table 2 below.

(23) ⊚: Length of footing of greater than 0 nm and 200 nm or less

(24) ∘: Length of footing of greater than 200 nm and 500 nm or less

(25) Δ: Length of footing of greater than 500 nm and 1 μm or less

(26) X: Length of footing of greater than 1 μm

(27) (3) Resistance to Plating Solution

(28) The photoresist compositions produced in Examples 1 to 5 and Comparative Example 1 were applied on a substrate with a spin coater and then subjected to processes such as prebaking and postbaking. The resist layer thus formed was immersed in a Cu plating solution at room temperature for 2 hours, and then the change in thickness of the resist layer was observed. The thickness change rate was measured based on the following criteria, and the results are shown in Table 2 below.

(29) ⊚: Thickness change rate of 1% or less

(30) ∘: Thickness change rate of greater than 1% and 5% or less

(31) Δ: Thickness change rate of greater than 5% and 10% or less

(32) X: Thickness change rate of greater than 10%

(33) (4) Heat Resistance

(34) The photoresist compositions prepared in Examples 1 to 5 and Comparative Example 1 were spin-coated on a glass substrate, dried on a hot plate at 120° C. for 2 minutes, exposed using a step mask, and then further dried on the hot plate at 100° C. for 2 minutes. Then, the coated wafer was sloped at 45° for 20 seconds and developed in a TMAH (tetramethylammonium hydroxide) aqueous solution. The heat resistance (perpendicularity of the pattern slope) was evaluated by measuring how much the produced thick film resist pattern was sloped. The results are shown in Table 2 based on the following criteria.

(35) ⊚: No slope

(36) ∘: greater than 0° and 5° or less

(37) Δ: greater than 5° and 10° or less

(38) X: greater than 10°

(39) TABLE-US-00002 TABLE 2 Sensitivity Developing Resistance to Heat (dose, mJ/cm.sup.2) property plating liquid resistance Example 1 420 ◯ ◯ ⊚ Example 2 400 ⊚ ⊚ ⊚ Example 3 360 ⊚ ⊚ ⊚ Example 4 380 ⊚ ⊚ ⊚ Example 5 340 ⊚ ⊚ ⊚ Comparative 480 Δ Δ ◯ Example 1

(40) From the results shown in Table 2, it can be seen that the photoresist compositions according to Examples 1 to 5 can obtain superior results in terms of sensitivity, developing property, resistance to plating solution, and heat resistance as compared with the photoresist composition according to Comparative Example 1.