Composition for Cleaning Photoresist Pattern

Abstract

The present invention provides a composition for cleaning photoresist patterns comprising a monoalcohol compound, an ester group compound of a specific structure, and water. The composition for cleaning photoresist patterns according to the present invention exhibits excellent cleaning power while preventing pattern collapse and damage during fine pattern cleaning, and can minimize the generation of impurities originating from the composition itself.

Description

Technology Field

[0001] The present invention relates to a composition for cleaning photoresist patterns, and more specifically, to a composition for cleaning photoresist patterns that can prevent pattern collapse and damage during cleaning of fine patterns having a high aspect ratio while exhibiting excellent cleaning power and minimizing the generation of impurities originating from the composition itself. Background Technology

[0002] In the photolithography process used to form fine structures in semiconductor manufacturing, as the pattern linewidth decreases and the aspect ratio increases, if the exposed area is developed with a developer and then washed and dried using commonly used deionized water, a phenomenon called pattern collapse occurs during the drying process due to capillary forces exerted by water droplets pulling on the fine pattern. To solve this problem, a method is being applied to reduce pattern defects occurring during the cleaning and drying process by using a cleaning solution with lower surface tension after treatment with the developer.

[0003] In addition, it has been reported that removing development residues that were not completely removed by the developer in the cleaning step after development increases the resolution of fine patterns and improves the overall process margin of the photolithography process; therefore, the composition used in the cleaning step is required to have appropriate cleaning power to remove residues on the bottom surface of the photoresist pattern.

[0004] However, approaching the issue from this perspective leads to the problem of dissolving photoresist patterns composed of organic compounds, particularly polymer compounds, causing the patterns themselves to deform; therefore, it is important that the cleaning composition does not cause damage to the photoresist patterns.

[0005] Korean Patent Publication No. 10-2017-0075438 discloses, as an example of a cleaning composition for preventing pattern collapse, a surfactant comprising a compound having a branched structure including a main chain containing a hydrophobic group and a plurality of side chains branched from the main chain and having at least one hydrophilic functional group, and a rinse solution for photolithography comprising deionized water.

[0006] However, the above rinse solution has a problem in that it is difficult to prevent the pattern from collapsing when cleaning fine patterns with a high aspect ratio, and the cleaned pattern is damaged or the rinse solution components remain, causing a large amount of impurities to be generated. Prior art literature

[0007] Republic of Korea Published Patent No. 10-2017-0075438 The problem to be solved

[0008] One objective of the present invention is to provide a composition for cleaning photoresist patterns that can prevent pattern collapse and damage during cleaning of fine patterns having a high aspect ratio, while exhibiting excellent cleaning power and minimizing the generation of impurities originating from the composition itself. means of solving the problem

[0009] On the other hand, the present invention provides a composition for cleaning a photoresist pattern comprising a monoalcohol compound, a compound represented by the following chemical formula 1, and water.

[0010] [Chemical Formula 1]

[0011]

[0012] In the above formula,

[0013] R 1 It is a hydrogen atom or a C1-C5 alkyl group, and

[0014] R 2 is a C2-C5 alkyl group, and

[0015] R 1 and R2 The sum of the carbon atoms included in is 6 or less.

[0017] In one embodiment of the present invention, the monoalcohol compound may be a C2-C5 monoalcohol compound.

[0018] In one embodiment of the present invention, the monoalcohol compound may have an octanol / water partition coefficient (Log P) calculated by the following mathematical formula 1 of -0.5 to 1.5.

[0019] [Mathematical Formula 1]

[0020] K ow = C o / C w

[0021] (C o : Concentration of alcohol compounds in octanol, C w : Concentration of alcohol compounds in water)

[0022] Log P (distribution coefficient) = Log (K ow ).

[0024] In one embodiment of the present invention, the monoalcohol compound may be one or more selected from the group consisting of ethanol, 1-propanol, 1-pentanol, and 1-methoxy-propanol.

[0025] In one embodiment of the present invention, the monoalcohol compound may be included in an amount of 0.1 to 20 weight% with respect to 100 weight% of the total composition.

[0026] In one embodiment of the present invention, the compound represented by Formula 1 may be one or more selected from the group consisting of ethyl propionate, propyl propionate, butyl propionate, and propionic acid.

[0027] In one embodiment of the present invention, the compound represented by Formula 1 may be included in an amount of 0.001 to 0.5 weight% with respect to 100 weight% of the total composition.

[0028] In one embodiment of the present invention, the water may be deionized water.

[0029] A composition for cleaning photoresist patterns according to one embodiment of the present invention may not include alkali compounds and fluorides. Effects of the invention

[0030] The composition for cleaning photoresist patterns according to the present invention can prevent pattern collapse and damage when cleaning fine patterns having a high aspect ratio, while exhibiting excellent cleaning power and minimizing the generation of impurities originating from the composition itself. Specific details for implementing the invention

[0031] The present invention will be described in more detail below.

[0033] One embodiment of the present invention relates to a composition for cleaning photoresist patterns comprising a monoalcohol compound, an ester compound of a specific structure, and water.

[0035] The photoresist pattern cleaning composition according to the present invention comprises a monoalcohol compound and an ester compound of a specific structure, which can prevent pattern collapse and damage when cleaning fine patterns having a high aspect ratio, while also removing developed residues during the cleaning process and minimizing the generation of impurities originating from the composition itself.

[0037] The components of a composition for cleaning photoresist patterns according to one embodiment of the present invention will be described in more detail below.

[0039] In one embodiment of the present invention, the composition for cleaning a photoresist pattern comprises a monoalcohol compound.

[0040] The composition for cleaning photoresist patterns according to the present invention includes the monoalcohol compound, thereby allowing the monoalcohol to dissolve in water and weaken hydrogen bonds between water molecules. Accordingly, the surface tension of water and the contact angle at the interface are reduced, which can suppress the phenomenon of photoresist patterns collapsing or being damaged during fine pattern cleaning.

[0042] As used in this specification, monoalcohol compounds refer to alcohol compounds having a saturated hydrocarbon group having 1 to 12 carbon atoms and one hydroxyl group.

[0043] In one embodiment of the present invention, the monoalcohol compound may be a C2-C5 monoalcohol compound.

[0045] In one embodiment of the present invention, the monoalcohol compound may have an octanol / water partition coefficient (Log P) calculated by the following mathematical formula 1, which is -0.5 to 1.5.

[0046] [Mathematical Formula 1]

[0047] K ow = C o / C w

[0048] (C o : Concentration of alcohol compounds in octanol, C w : Concentration of alcohol compounds in water)

[0049] Log P (distribution coefficient) = Log (K ow )

[0051] The aforementioned partition coefficient is the ratio of the concentration of a compound in a mixture of two immiscible solvents at equilibrium. This allows for the prediction of the water dispersibility of the compound to be dissolved; a high partition coefficient indicates low water dispersibility, while a low partition coefficient indicates high water dispersibility.

[0052] If the above distribution coefficient is less than -0.5, it is difficult to expect the effect of preventing pattern collapse during cleaning, and if it exceeds 1.5, the photoresist pattern may be damaged due to cleaning, or a large amount of impurities may be generated from the composition itself.

[0053] Monoalcohol compounds having a distribution coefficient of -0.5 to 1.5 include, but are not limited to, ethanol, 1-propanol, 1-pentanol, 1-methoxy-propanol, etc.

[0055] In one embodiment of the present invention, the monoalcohol compound may be included in an amount of 0.1 to 20 weight%, preferably 0.5 to 10 weight%, based on 100 weight% of the total composition. If the content of the monoalcohol compound is less than 0.5 weight%, the effect of preventing pattern collapse during cleaning is negligible, and if it exceeds 20 weight%, the photoresist pattern may be damaged or the pattern may dissolve, resulting in a lower residual film rate, which may make it difficult to obtain a pattern with a high aspect ratio.

[0057] In one embodiment of the present invention, the photoresist pattern cleaning composition comprises a compound represented by the following chemical formula 1.

[0058] [Chemical Formula 1]

[0059]

[0060] In the above formula,

[0061] R 1 It is a hydrogen atom or a C1-C5 alkyl group, and

[0062] R 2 is a C2-C5 alkyl group, and

[0063] R 1 and R 2 The sum of the carbon atoms included in is 6 or less.

[0065] The composition for cleaning a photoresist pattern according to the present invention uses a compound represented by Chemical Formula 1 together with a monoalcohol compound, thereby lowering the contact angle on the surface of the fine pattern during cleaning after the photoresist development process, which can prevent the pattern from collapsing and minimize damage to the photoresist pattern.

[0067] As used in this specification, C1-C5 alkyl groups refer to straight-chain or branched monovalent hydrocarbons having 1 to 5 carbon atoms, and include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, etc.

[0068] As used in this specification, C2-C5 alkyl groups refer to straight-chain or branched monovalent hydrocarbons having 2 to 5 carbon atoms, and include, but are not limited to, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, etc.

[0070] The compound represented by the above chemical formula 1 may be one or more selected from the group consisting of ethyl propionate, propyl propionate, butyl propionate, and propionic acid, but is not limited thereto.

[0072] In one embodiment of the present invention, the compound represented by Formula 1 may be included in an amount of 0.001 to 0.5 weight%, preferably 0.005 to 0.3 weight%, based on 100 weight% of the total composition. If the content is less than 0.001 weight%, it is difficult to expect an effect of preventing pattern collapse, and if it exceeds 0.5 weight%, there may be a problem in which the photoresist pattern is damaged or dissolved, resulting in a decrease in film thickness.

[0074] A composition for cleaning a photoresist pattern according to one embodiment of the present invention includes water as a solvent, wherein the water may be included as a remainder other than other components.

[0075] In one embodiment of the present invention, the water may be deionized water (DIW). When deionized water is used, the process cost is reduced, and handling and wastewater treatment are easy.

[0076] In addition, as mentioned above, since the water is included as a remainder, the water content may vary depending on the content of the constituent(s) included in the composition for cleaning photoresist patterns.

[0078] In addition, the composition for cleaning photoresist patterns of the present invention may further include conventional additives in addition to the aforementioned components to further improve the effect.

[0080] A composition for cleaning a photoresist pattern according to one embodiment of the present invention may not include alkali compounds and fluorides in order to minimize damage to the photoresist pattern.

[0081] The above alkali compound can dissolve the photoresist pattern composed of polymer components, causing deformation and peeling of the pattern shape, and the above fluoride can remain after cleaning and increase the generation of impurities.

[0083] The composition for cleaning a photoresist pattern according to the present invention can be suitably used in a cleaning process after developing a photoresist pattern.

[0085] The present invention will be explained more specifically below through examples, comparative examples, and experimental examples. These examples, comparative examples, and experimental examples are intended solely to illustrate the present invention, and it is obvious to those skilled in the art that the scope of the present invention is not limited thereto.

[0087] Examples 1 to 22 and Comparative Examples 1 to 10: Preparation of a composition for cleaning photoresist patterns

[0088] A composition for cleaning photoresist patterns was prepared by mixing each component as shown in Tables 1 and 2 below (Unit: weight%).

[0089] monoalcohol compounds ester compounds DIW A-1 A-2 A-3 A-4 A-5 A-6 A-7 B-1 B-2 B-3 B-4 C Example 1 3 　 　 　 　 　 　 0.05 　 　 　 96.95 Example 2 　 3 　 　 　 　 　 0.05 　 　 　 96.95 Example 3 　 　 3 　 　 　 　 0.05 　 　 　 96.95 Example 4 　 　 　 3 　 　 　 0.05 　 　 　 96.95 Example 5 　 　 　 　 　 　 3 0.05 　 　 　 96.95 Example 6 　 　 0.05 　 　 　 　 0.05 　 　 　 99.9 Example 7 　 　 0.1 　 　 　 　 0.05 　 　 　 99.85 Example 8 　 　 0.5 　 　 　 　 0.05 　 　 　 99.45 Example 9 　 　 1 　 　 　 　 0.05 　 　 　 98.95 Example 10 　 　 5 　 　 　 　 0.05 　 　 　 94.95 Example 11 　 　 10 　 　 　 　 0.05 　 　 　 89.95 Example 12 　 　 15 　 　 　 　 0.05 　 　 　 84.95 Example 13 　 　 20 　 　 　 　 0.05 　 　 　 79.95 Example 14 　 　 22 　 　 　 　 0.05 　 　 　 77.95 Example 15 　 10 　 　 　 　 　 0.001 　 　 　 89.999 Example 16 　 10 　 　 　 　 　 0.005 　 　 　 89.995 Example 17 　 10 　 　 　 　 　 0.3 　 　 　 89.7 Example 18 　 10 　 　 　 　 　 0.5 　 　 　 89.5 Example 19 　 10 　 　 　 　 　 0.7 　 　 　 89.3 Example 20 　 10 　 　 　 　 　 　 0.5 　 　 89.5 Example 21 　 10 　 　 　 　 　 　 　 0.5 　 89.5 Example 22 　 10 　 　 　 　 　 　 　 　 0.5 89.5

[0091] monoalcohol compounds ester compounds DIW A-1 A-2 A-3 A-4 A-5 A-6 A-7 B-1 B-2 B-3 B-4 C Comparative Example 1 　 　 　 　 　 10 　 　 　 　 　 90 Comparative Example 2 　 　 　 　 　 10 　 0.5 　 　 　 89.5 Comparative Example 3 　 　 　 　 10 　 　 0.5 　 　 　 89.5 Comparative Example 4 　 30 　 　 　 　 　 　 　 　 　 70 Comparative Example 5 　 　 　 　 　 100 　 　 　 　 　 0 Comparative Example 6 　 10 　 　 　 　 　 　 　 　 　 90 Comparative Example 7 　 10 　 　 　 10 　 　 　 　 　 80 Comparative Example 8 　 10 　 　 　 　 　 1 　 　 　 89 Comparative Example 9 　 10 　 　 10 　 　 　 　 　 　 80 Comparative Example 10 0.5 99.5

[0093] A-1: Ethanol (LogP -0.18)

[0094] A-2: 1-Propanol (LogP 0.329)

[0095] A-3: 1-Pentanol (LogP 1.210)

[0096] A-4: 1-Methoxy-Propanol (LogP -0.11)

[0097] A-5: Ethylene glycol (LogP -0.47)

[0098] A-6: Methanol (LogP -0.69)

[0099] A-7: Hexanol (LogP 2.03)

[0100] B-1: Ethyl propionate

[0101] B-2: Profile Propionate

[0102] B-3: Butyl propionate

[0103] B-4: Propionic acid

[0105] Experimental Example 1:

[0106] After forming a photoresist pattern according to the method below, a cleaning process was performed using the photoresist pattern cleaning composition of the above examples and comparative examples, and then pattern collapse and pattern damage were evaluated, and the results are shown in Tables 3 and 4 below.

[0108] <Photoresist Pattern Formation and Cleaning Method>

[0109] A lower anti-reflective film (DUV42P-6, Nissan Chemical Industries) was spin-coated onto a silicon substrate and heated at 215°C for 90 seconds to form a film with a thickness of 600 Å. A PHS-type photosensitive material (KTF-5664, Dongwoo Finechem) was spin-coated on top of it to prepare a photoresist thin film, and then soft-baked in an oven at 100°C for 60 seconds. After soft-baking, the film was exposed using a scanner equipped with a KrF laser and post-baked again in an oven at 110°C for 60 seconds.

[0110] After post-baking was completed, the wafer was immersed in a 2.38 wt% aqueous tetramethylammonium hydroxide (TMAH) solution for 60 seconds for development, and then the development residue was removed using deionized water. Then, 30 mL of the cleaning solution composition prepared in the examples and comparative examples was applied to the silicon wafer surface for 10 seconds, and the wafer was dried by high-speed spinning to obtain an 180 nm L / S pattern.

[0112] (1) Pattern Collapse

[0113] The degree of collapse of the 180nm L / S pattern was observed using a CD-SEM (Hitachi) and evaluated according to the following evaluation criteria.

[0114] <Evaluation Criteria>

[0115] ○: No pattern collapse occurs

[0116] △: Collapse occurs only in edge patterns

[0117] ×: Collapse occurs in the edge and central patterns

[0119] (2) Degree of damage to the photoresist pattern

[0120] The difference in thickness of the photoresist pattern before and after treatment with the photoresist pattern cleaning composition was measured using an FE-SEM (Hitachi) to determine the degree of thickness reduction, and the degree of damage to the photoresist pattern was evaluated according to the following evaluation criteria. A smaller difference in thickness indicates that the photoresist pattern has suffered less damage.

[0121] <Evaluation Criteria>

[0122] ○: Photoresist thickness reduction 50 Å or less

[0123] △: Photoresist thickness reduction greater than 50 Å and less than or equal to 100 Å

[0124] ×: Photoresist thickness reduction exceeding 100 Å

[0126] Experimental Example 2: Degree of residual particle generation

[0127] After filtering the photoresist pattern cleaning compositions of the examples and comparative examples through a 0.01 μm size filter, Rion's liquid particle counter <ks-18f>After flowing the sample for about 30 minutes, the number of particles with a size of 100 nm was measured. The evaluation was conducted according to the following criteria, and the results are shown in Tables 3 and 4 below.

[0128] <Evaluation Criteria>

[0129] ○: Less than 100

[0130] △: 100 or more, less than 300

[0131] ×: 300 or more

[0133] Pattern collapse Pattern damage residual particles Example 1 O O O Example 2 O O O Example 3 O O O Example 4 △ O O Example 5 O △ △ Example 6 △ O O Example 7 O O O Example 8 O O O Example 9 O O O Example 10 O O O Example 11 O O O Example 12 O O O Example 13 O O O Example 14 O △ O Example 15 O O O Example 16 O O O Example 17 O O O Example 18 O O O Example 19 O △ O Example 20 O O O Example 21 O O △ Example 22 O O O

[0135] Pattern collapse Pattern damage residual particles Comparative Example 1 X O O Comparative Example 2 X O O Comparative Example 3 X O O Comparative Example 4 O X O Comparative Example 5 O X O Comparative Example 6 X O O Comparative Example 7 O X X Comparative Example 8 O X O Comparative Example 9 △ △ X Comparative Example 10 X O O

[0137] As shown in Table 3 above, it was confirmed that the photoresist pattern cleaning compositions of Examples 1 to 22, which include a monoalcohol compound and an ester compound of a specific structure, can suppress pattern collapse and prevent pattern damage during fine pattern cleaning, and can suppress the generation of residual particles caused by the components of the composition.

[0138] On the other hand, as shown in Table 4, it was confirmed that the photoresist pattern cleaning compositions of Comparative Examples 1 to 10 could not prevent the pattern from collapsing during fine pattern cleaning, or that damage occurred to the pattern, or that a large amount of residual particles were generated.

[0140] As specific parts of the present invention have been described in detail above, it is evident to those skilled in the art that such specific descriptions are merely preferred embodiments and do not limit the scope of the present invention. Those skilled in the art will be able to make various applications and modifications within the scope of the present invention based on the above description.

[0141] Accordingly, the substantial scope of the present invention shall be defined by the appended claims and their equivalents.

Claims

Claim 1 A composition for cleaning photoresist patterns comprising a monoalcohol compound, a compound represented by the following chemical formula 1, and water: [Chemical Formula 1] In the above equation, R 1 is a hydrogen atom or a C1-C5 alkyl group, and R 2 is a C2-C5 alkyl group, and R 1 and R 2 The sum of the carbon atoms included in is 6 or less. Claim 2 A composition for cleaning photoresist patterns according to claim 1, wherein the monoalcohol compound is a C2-C5 monoalcohol compound. Claim 3 In claim 1, the monoalcohol compound is a photoresist pattern cleaning composition having an octanol / water partition coefficient (Log P) calculated by the following Equation 1 (Equation 1) of -0.5 to 1.5: [Equation 1]K ow = C o / C w (C o : Concentration of alcohol compounds in octanol, C w : Concentration of alcohol compound in water) Log P (partition coefficient) = Log (K ow ). Claim 4 A composition for cleaning photoresist patterns according to claim 1, wherein the monoalcohol compound is one or more selected from the group consisting of ethanol, 1-propanol, 1-pentanol, and 1-methoxy-propanol. Claim 5 A photoresist pattern cleaning composition according to claim 1, wherein the monoalcohol compound is included in an amount of 0.1 to 20 weight% based on 100 weight% of the total composition. Claim 6 A composition for cleaning photoresist patterns according to claim 1, wherein the compound represented by Chemical Formula 1 is one or more selected from the group consisting of ethyl propionate, propyl propionate, butyl propionate, and propionic acid. Claim 7 A photoresist pattern cleaning composition according to claim 1, wherein the compound represented by Chemical Formula 1 is included in an amount of 0.001 to 0.5 weight% with respect to 100 weight% of the total composition. Claim 8 A composition for cleaning photoresist patterns according to claim 1, wherein the water is deionized water. Claim 9 A composition for cleaning photoresist patterns according to claim 1, which does not contain alkali compounds and fluorides.

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