Photoresist pattern shrinking composition and pattern shrinking method

Abstract

Provided is a composition for shrinking a photoresist pattern, which is capable of shrinking a photoresist pattern using a photoresist during the fabrication of a semiconductor, and to a method of shrinking a pattern using the composition, whereby a pattern to be formed can be shrunken in a photoresist-patterning process, thus remarkably decreasing the number of steps of a semiconductor fabrication process and reducing the fabrication time and costs.

Claims

1. A composition for shrinking a photoresist pattern on a wafer, the composition comprising: 20 to 80 wt % of a pattern-shrinking material for shrinking the photoresist pattern on the wafer; 20 to 80 wt % of a solvent; and 0.01 to 2 wt % of a surfactant, wherein the surfactant is polyoxyethylene nonylphenylether, wherein the pattern-shrinking material is any one or a mixture of two or more selected from the group consisting of acetyl carbitol as a C1-C10 ketone-based solvent; ethylene glycol or triethylene glycol monoethylether as a C1-C10 ether-based solvent; and diethylene glycol monobutylether acetate as a C1-C10 ester-based solvent, and wherein the solvent is 2-heptanol.

2. A method of shrinking a photoresist pattern on a wafer, the method comprising: (1) dispensing a composition for shrinking the photoresist pattern on the photoresist pattern on the wafer; (2) puddling for a predetermined period of time; and (3) spin drying, wherein the composition for shrinking the photoresist pattern comprises: 20 to 80 wt % of a pattern-shrinking material for shrinking the photoresist pattern on the wafer; 20 to 80 wt % of a solvent; and 0.01 to 2 wt % of a surfactant, wherein the surfactant is polyoxyethylene nonylphenylether, wherein the pattern-shrinking material is any one or a mixture of two or more selected from the group consisting of acetyl carbitol as a C1-C10 ketone-based solvent; ethylene glycol or triethylene glycol monoethylether as a C1-C10 ether-based solvent; and diethylene glycol monobutylether acetate as a C1-C10 ester-based solvent, and wherein the solvent is 2-heptanol.

3. The method of claim 2, wherein the puddling is performed for 20 to 120 seconds.

Description

BRIEF DESCRIPTION OF DRAWING

(1) FIG. 1 shows scanning electron microscopy images of photoresist patterns of Comparative Test Example 1 and Test Example 1.

BEST MODE

(2) Hereinafter, a detailed description will be given of the present invention.

(3) The present invention pertains to a composition and method for shrinking a pattern in a photoresist-patterning process.

(4) In the present invention, the composition for shrinking a pattern comprises 1 to 100 wt % of a pattern-shrinking material for shrinking a photoresist pattern, 0 to 99 wt % of a solvent, and 0 to 2 wt % of a surfactant.

(5) In the present invention, the method of shrinking a pattern includes dispensing at a speed of 5 to 50 mL/s for 1 to 20 sec, puddling for 5 to less than 120 sec, and spin drying.

(6) Generally, during the fabrication of a semiconductor, a pattern is shrunken in a manner in which an appropriate pattern-shrinking material (RELACS) is applied on a semiconductor substrate having a predetermined pattern, and is then baked to form a crosslinking layer between the RELACS layer and the photoresist film, after which the RELACS layer, which is not crosslinked but remains, is removed using an appropriate cleaning material.

(7) The present invention pertains to a processing solution composition comprising a pattern-shrinking material, which is capable of shrinking a pattern through dispensing, puddling for a predetermined period of time and then spin drying, and to a method of shrinking a pattern using the composition.

(8) The pattern-shrinking material may include at least one selected from among an alcohol or a derivative thereof, an amide-based solvent, a ketone-based solvent, an ether-based solvent, an ester-based solvent and a hydrocarbon-based solvent.

(9) Specific examples of the alcohol or the derivative thereof may include C1-C5 alcohols and derivatives thereof, such as methanol, ethanol, 2-butoxy ethanol, N-propanol, 2-propanol, 1-butoxy-2-propanol, 2-methyl-2-propanol, 1-butanol, 2-butanol, 2-methyl-2-butanol, 3-methyl-1-butanol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-pentanol, 2-methyl-3-pentanol, 2,3-dimethyl-3-pentanol, and 4-methyl-2-pentanol.

(10) Specific examples of the amide-based solvent may include C1-C10 amide-based solvents, such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, and 1,3-dimethyl-2-imidazolidinone.

(11) Specific examples of the ketone-based solvent may include C1-C10 ketone-based solvents, such as 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, 1-hexanone, 2-hexanone, 4-heptanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, diacetonyl alcohol, and acetyl carbitol.

(12) Specific examples of the ether-based solvent may include C1-C10 ether-based solvents, such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, monomethylether, methoxymethyl butanol, diethylether, ethylene glycol monomethylether, propylene glycol monomethylether, propylene glycol monoethylether, diethylene glycol monomethylether, and triethylene glycol monoethylether.

(13) Specific examples of the ester-based solvent may include C1-C10 ester-based solvents, such as propylene glycol monomethylether acetate, ethylene glycol monoethylether acetate, diethylene glycol monobutylether acetate, and diethylene glycol monoethylether acetate.

(14) Specific examples of the hydrocarbon-based solvent may include C1-C10 hydrocarbon-based solvents, such as pentane, hexane, octane, and decane.

(15) The amount of the pattern-shrinking material may be 1 to 100 wt %.

(16) The solvent is not particularly limited, so long as it does not dissolve the resist pattern, and the solvent may be efficiently mixed with the above pattern-shrinking material, and a solution including a typical organic solvent may be used. Particularly preferable examples of the solvent may include monohydric alcohols, such as 1-pentanol, 2-pentanol, 1-hexanol, 1-heptanol, 1-octanol, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-octanol, 4-octanol, 1-butanol, 2-butanol, 3-methyl-1-butanol, and tert-butyl alcohol, and ester-based solvents, such as butyl acetate, amyl acetate, ethyl-3-ethoxypropionate, 3-methoxybutylacetate, 3-methyl-3-methoxybutylacetate, butyl formate, propyl formate, ethyl lactate, and butyl lactate.

(17) The amount of the solvent may be 0 to 99 wt %.

(18) The surfactant may be any one or a mixture of two or more selected from the group consisting of nonionic surfactants, such as polyoxyethylene alkylethers, polyoxyethylene alkylphenylethers, polyoxyethylene nonylphenylethers, polyoxyethylene octylphenylethers, polyoxyethylene polyoxypropylenes, polyoxyethylene laurylethers, and polyoxyethylene sorbitans.

(19) The surfactant plays a role in decreasing surface tension to thus increase spreadability or penetrability, thus aiding in shrinking a pattern.

(20) The amount of the surfactant may be 0 to 2 wt %.

(21) When the composition for shrinking a photoresist pattern is applied to the processing method, it is essential to set an appropriate process and a processing time because the photoresist formed on a normal pattern has to be finely shrunken to the level of ones of nm. The critical shrinkage rate upon pattern shrinking is 10% or more (5 nm or more in a 50 nm pattern). Although there is a difference depending on the kind of processing solution, when the puddle time is below 5 sec in the process of shrinking a photoresist pattern on a 300 mm wafer, the shrinkage effect is low and thus there is almost no pattern shrinkage effect. On the other hand, when the puddle time is above 120 sec, the processing time is increased and excessive shrinkage is caused, and thus pattern CDU becomes poor. Hence, the puddle time is preferably set to the range of 5 sec to 120 sec.

(22) In a typical photoresist-patterning process, a photoresist photosensitive to ArF is applied through spin coating at 1500 rpm on a 300 mm silicon wafer using a spin coater, dried (SB: Soft Baking) on a hot plate at 120° C. for 60 sec, exposed using an exposure machine for generating ArF, dried (PEB: Post-Exposure Baking) on a hot plate at 120° C. for 60 sec, and developed for 30 sec using a developing solution.

(23) In the present invention, after the typical photoresist-patterning process, the processing solution for shrinking a photoresist pattern is dispensed at 100 rpm at a speed of 15 mL/s for 10 sec, and puddled for 20 sec, followed by rotating the wafer at 4000 rpm for 20 sec, thereby completing the formation of a photoresist pattern.

(24) The above process is described by way of example, and the processing time is not limited thereto.

(25) As described hereinbefore, the composition for shrinking a photoresist pattern and the processing method using the composition enable a small pattern surface to be appropriately shrunken, whereby a high processing margin may be provided during subsequent etching or implanting processes, ultimately increasing production yield and thus reducing fabrication costs.

(26) A better understanding of the present invention will be given through the following examples and comparative example, in which the examples are set forth merely to illustrate the present invention, but are not to be construed as limiting the scope thereof.

Mode for Invention

Example 1

(27) A composition for shrinking a photoresist pattern, comprising 20 wt % of ethanol and 80 wt % of 2-heptanol, was prepared as follows.

(28) Ethanol was added with 2-heptanol, stirred for 6 hr, and passed through a 0.02 μm filter, thus preparing a composition for shrinking a photoresist pattern.

Examples 2 to 28

(29) Respective compositions for shrinking a photoresist pattern were prepared in the same manner as in Example 1 using the components in the amounts shown in Table 1 below.

Comparative Example

(30) Butyl acetate, used as a final cleaning solution for a negative tone development process during the fabrication of a semiconductor device, was provided.

Test Example 1

(31) A photoresist photosensitive to ArF was applied through spin coating on a 300 mm silicon wafer at 1500 rpm using a spin coater, dried (SB: Soft Baking) on a hot plate at 120° C. for 60 sec, exposed using an exposure machine for generating ArF, dried (PEB: Post-Exposure Baking) on a hot plate at 120° C. for 60 sec, and developed (negative tone development) for 30 sec using a negative tone developing solution (butyl acetate). Thereafter, the composition for shrinking the pattern prepared in Example 1 was dispensed at 100 rpm at a speed of 15 mL/s for 10 sec and was then puddled for 20 sec, and the wafer was rotated at 4000 rpm for 20 sec, thereby completing the formation of a photoresist pattern. Here, the formed pattern size was 50 nm.

Test Examples 2 to 59

(32) Respective patterns were formed in the same manner as in Test Example 1 using the compositions of Examples 1 to 28, except for the puddle time in the pattern-shrinking process.

Comparative Test Examples 1 and 2

(33) Respective patterns were formed in the same manner as in Test Example 1 using butyl acetate of Comparative Example as the processing solution, except for the puddle time in the pattern-shrinking process.

(34) For the silicon wafers having the patterns of Test Examples 1 to 59 and

(35) Comparative Test Examples 1 and 2, pattern CD (Critical Dimension) sizes were measured, and the extent of shrinkage of the pattern was determined. The results are shown in Table 2 below.

(36) (1) CD (Critical Dimension) size

(37) The difference between the X-axis and the Y-axis of the pattern was measured using a scanning electron microscope (FE-SEM, Hitachi), and thus the CD values were determined. After treatment, a 50 nm hole pattern was measured in the present test.

(38) TABLE-US-00001 TABLE 1 Pattern- shrinking material Solvent Surfactant Amount Amount Amount Name (wt %) Name (wt %) Name (wt %) Example 1 Ethanol 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 2 Ethanol 50 2-heptanol 50 Polyoxyethylene nonylphenylether Example 3 Ethanol 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 4 Ethanol 20 2-heptanol 79.9 Polyoxyethylene 0.1 nonylphenylether Example 5 Ethanol 20 2-heptanol 78 Polyoxyethylene 2 nonylphenylether Example 6 2-pentanol 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 7 2-pentanol 50 2-heptanol 50 Polyoxyethylene nonylphenylether Example 8 2-pentanol 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 9 Acetamide 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 10 Acetamide 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 11 4-4-methoxy-2- 20 2-heptanol 80 Polyoxyethylene phenyl nonylphenylether glycinamide Example 12 4-4-methoxy-2- 80 2-heptanol 20 Polyoxyethylene phenyl nonylphenylether glycinamide Example 13 Methyl ethyl 20 2-heptanol 80 Polyoxyethylene ketone nonylphenylether Example 14 Methyl ethyl 80 2-heptanol 20 Polyoxyethylene ketone nonylphenylether Example 15 Acetyl carbitol 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 16 Acetyl carbitol 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 17 Ethylene glycol 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 18 Ethylene glycol 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 19 Triethylene glycol 20 2-heptanol 80 Polyoxyethylene monoethyl ether nonylphenylether Example 20 Triethylene glycol 80 2-heptanol 20 Polyoxyethylene monoethyl ether nonylphenylether Example 21 Methyl acetate 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 22 Methyl acetate 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 23 Diethylene glycol 20 2-heptanol 80 Polyoxyethylene monobutyl ether nonylphenylether acetate Example 24 Diethylene glycol 80 2-heptanol 20 Polyoxyethylene monobutyl ether nonylphenylether acetate Example 25 Pentane 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 26 Pentane 80 2-heptanol 20 Polyoxyethylene nonylphenylether Example 27 Decane 20 2-heptanol 80 Polyoxyethylene nonylphenylether Example 28 Decane 80 2-heptanol 20 Polyoxyethylene nonylphenylether Comparative Butyl acetate 100 Example

(39) TABLE-US-00002 TABLE 2 Shrinkage rate Puddle Pattern (%) (based on time CD Size non-treatment Composition (sec) (nm) group) Test Example 1 Example 1 20 35.2 29.6 Test Example 2 Example 1 120 22.0 56.0 Test Example 3 Example 2 20 24.1 51.8 Test Example 4 Example 2 120 10.2 79.6 Test Example 5 Example 3 20 14.9 70.2 Test Example 6 Example 3 120 4.5 91.0 Test Example 7 Example 4 20 34.8 30.4 Test Example 8 Example 4 120 21.9 56.2 Test Example 9 Example 5 20 34.7 30.6 Test Example 10 Example 5 120 21.7 56.6 Test Example 11 Example 6 20 37.0 26.0 Test Example 12 Example 6 120 23.5 53.0 Test Example 13 Example 7 20 34.2 31.6 Test Example 14 Example 7 120 20.2 59.6 Test Example 15 Example 8 20 16.0 68.0 Test Example 16 Example 8 120 5.4 89.2 Test Example 17 Example 9 20 38.8 22.4 Test Example 18 Example 9 120 25.2 49.6 Test Example 19 Example 10 20 27.7 44.6 Test Example 20 Example 10 120 6.6 86.8 Test Example 21 Example 11 20 40.2 19.6 Test Example 22 Example 11 120 31.2 37.6 Test Example 23 Example 12 20 22.8 54.4 Test Example 24 Example 12 120 8.8 82.4 Test Example 25 Example 13 20 36.8 26.4 Test Example 26 Example 13 120 23.2 53.6 Test Example 27 Example 14 20 19.2 61.6 Test Example 28 Example 14 120 5.6 88.8 Test Example 29 Example 15 20 37.2 25.6 Test Example 30 Example 15 120 24.3 51.4 Test Example 31 Example 16 20 26.3 47.4 Test Example 32 Example 16 120 10.8 78.4 Test Example 33 Example 17 20 39.5 21.0 Test Example 34 Example 17 120 23.8 52.4 Test Example 35 Example 18 20 26.2 47.6 Test Example 36 Example 18 120 9.7 80.6 Test Example 37 Example 19 20 38.1 23.8 Test Example 38 Example 19 120 22.2 55.6 Test Example 39 Example 20 20 23.1 53.8 Test Example 40 Example 20 120 9.2 81.6 Test Example 41 Example 21 20 39.5 21.0 Test Example 42 Example 21 120 25.2 49.6 Test Example 43 Example 22 20 28.4 43.2 Test Example 44 Example 22 120 13.7 72.6 Test Example 45 Example 23 20 38.5 23.0 Test Example 46 Example 23 120 22.9 54.2 Test Example 47 Example 24 20 24.1 51.8 Test Example 48 Example 24 120 6.2 87.6 Test Example 49 Example 25 20 38.4 23.2 Test Example 50 Example 25 120 21.6 56.8 Test Example 51 Example 26 20 22.7 54.6 Test Example 52 Example 26 120 6.9 86.2 Test Example 53 Example 27 5 44.9 10.2 Test Example 54 Example 27 10 43.9 12.2 Test Example 55 Example 27 15 43.3 13.4 Test Example 56 Example 27 20 42.8 14.4 Test Example 57 Example 27 120 28.5 43.0 Test Example 58 Example 28 20 29.5 41.0 Test Example 59 Example 28 120 15.7 68.6 Comparative Test Comparative Non- 50.0 0.0 Example 1 Example treatment group Comparative Test Comparative 20 47.0 6.0 Example 2 Example

(40) In the above Examples and Test Examples, the following can be confirmed.

(41) The pattern size can be concluded to be variously controlled by adjusting the amount of the pattern-shrinking material, such as the alcohol or derivative thereof, amide-based solvent, ketone-based solvent, ether-based solvent, ester-based solvent or hydrocarbon-based solvent, or the puddle time in the process according to the present invention.