Chemically amplified positive photoresist composition for improving pattern profile and adhesion

Abstract

The present invention relates to a chemically amplified positive photoresist composition for improving pattern profile and adhesion, which can be exposed with a light source having a wavelength of 248 nm and contains 1 to 5 wt % of a polyhydric alcohol additive represented by Chemical Formulas 1 to 8 based on the total weight of the composition to achieve a vertical profile without pattern collapse.

Description

[Technical Field]

[0001] The present invention relates to chemically amplified positive photoresist compositions for use in improving pattern profile and promoting adhesion between the pattern and the substrate. [Background technology]

[0002] In recent years, with the advancement of semiconductor manufacturing technology, there has been a demand for miniaturization and high integration of semiconductor devices, leading to a demand for technology that can realize ultra-fine patterns with line widths of tens of nanometers or less. Technological advances for forming such ultra-fine patterns have been made possible by the development of light sources with smaller wavelengths, process technologies using light sources, and photoresists suitable for light sources. Photoresist is used in photolithography to form various patterns. Photoresist is a photosensitive resin that changes its solubility in a developer when exposed to light, allowing an image corresponding to the exposed pattern to be obtained. The photoresist pattern forming method includes a method using a negative tone developer (NTD, Negative Tone Development) and a method using a positive tone developer (PTD, Positive Tone Development). The pattern formation method using a negative developer is a method of forming a pattern by selectively dissolving and removing non-exposed regions with a negative developer, and the pattern formation method using a positive developer is a method of forming a pattern by selectively dissolving and removing exposed regions with a positive developer. Compared with pattern formation methods using positive developer solutions, the pattern formation method using a negative developer solution can realize reverse-phase patterns even in contact hole patterns and trench patterns that are difficult to form due to insufficient exposure dose, making it easier to form patterns when realizing the same pattern. Furthermore, since an organic solvent is used as a developer solution to remove unexposed portions, photoresist patterns can be formed more effectively.

[0003] Meanwhile, a photolithography process using a photoresist composition generally includes the steps of coating a photoresist on a wafer, a soft baking process in which the coated photoresist is heated to evaporate the solvent, an imaging process using a light source passing through a photomask, a process in which a pattern is formed using a developer due to the difference in solubility between exposed and unexposed areas, and a process in which the pattern is etched to complete a circuit. The photoresist composition is composed of a photoacid generator that generates acid when irradiated with an excimer laser, a base resin, and other additives. The base resin has a structure with a hydroxyl group in a phenolic structure, and is generally a polystyrene polymer. The photoacid generator generates acid (H + Any of these can be used as long as it can generate a sulfonium salt, sulfonyldiazot, benzosulfonyl, iodine, chlorine, and carboxylic acid. In addition, the light sources mainly used in the above-mentioned process are in the wavelength range of 365 nm to 193 nm using i-line, KrF excimer laser, and ArF excimer laser light sources, and it is known that the shorter the wavelength, the finer the patterns that can be formed. Among these, KrF laser (248nm) photoresists continue to be a focus of research and development in pursuit of optical microfabrication, despite the subsequent development of ArF laser (193nm) systems. While the development of next-generation ArF photoresists is still lacking, the use of KrF~i-Line photoresists offers significant cost-saving benefits in semiconductor mass production. To keep pace with these technological developments, the performance of KrF~i-Line photoresists must also improve. For example, as higher integration requires thinner photoresists, there is a pressing need for photoresists with improved dry etching resistance. Other required characteristics include high resolution, a wide depth of focus (DOF), defect-free thin film formation, strong adhesion to the substrate, high contrast, high speed sensitivity, and chemical stability.

[0004] As mentioned above, prior patents relating to KrF~i-Line photoresist technology include Korean Patent Publication No. 10-0047038 entitled "Chemically Amplified Positive Photoresist Composition," Korean Patent Publication No. 10-1363842 entitled "Chemically Amplified Positive Photoresist Composition and Method for Forming Resist Pattern Using the Same," Korean Patent Publication No. 10-1204915 entitled "Photoresist Polymer, Photoresist Composition Containing the Same, and Method for Forming Photoresist Pattern Using the Same," Korean Patent Publication No. 10-0273108 entitled "Copolymer for Producing Photoresist and Chemically Amplified Positive Photoresist Composition Containing the Same," Korean Patent Publication No. 10-1655947 entitled "Negative Photoresist Composition for KrF Laser Having High Resolution and High Aspect Ratio," and Korean Patent Publication No. 10-1977886 entitled "Chemically Amplified Positive Photoresist Composition for Improving Pattern Profile." As described in the above patents, KrF~i-Line photoresists mainly use polyhydroxystyrene and polystyrene polymers as base polymers, which have good transmittance in the wavelength range of 248nm~365nm, in order to improve resolution and sensitivity. Positive photoresists based on polyhydroxystyrene and polystyrene polymers have limitations in the range of usable light sources in processes based on 248nm to 365nm due to slope pattern shapes or footing phenomena, and as the photoresist thickness increases, the achievable resolution decreases. Furthermore, depending on the type of underlying film, problems such as insufficient adhesion can cause process issues such as pattern collapse. These drawbacks are major issues. Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention aims to provide a photoresist composition for KrF to i-Line light sources, which has an improved pattern profile and no pattern collapse compared to conventional KrF to i-Line positive photoresists, by adding an appropriate amount of polyhydric alcohol additive, which is effective in improving pattern profile and increasing adhesion between the pattern and underlying film, thereby improving process margins. That is, the object is to provide a photoresist composition for KrF to i-Line light sources that can ensure a vertical profile, thereby improving the pattern profile, and can ensure stable adhesion between the pattern and the underlying film, thereby preventing pattern collapse. [Means for solving the problem]

[0006] To achieve the above object, the present invention provides a positive photoresist composition for KrF to i-Line light sources, which contains a polyhydric alcohol additive having a molecular weight of 100 to 200, for enhancing adhesion between a chemically amplified resist pattern and an underlying film, and is represented by the following Chemical Formulas 1 to 8: [Chemical formula 1] [ka] [Chemical formula 2] [ka] [Chemical formula 3] [ka] [Chemical formula 4] [ka] [Chemical formula 5] [ka] [Chemical formula 6] [ka] [Chemical formula 7] [ka] [Chemical formula 8] [ka] In a preferred embodiment of the present invention, polyhydric alcohol additives for enhancing adhesion between a resist pattern and underlying film materials, as represented by the above chemical formula and similar structures, are commercially available from a number of domestic and international suppliers.

[0007] In a preferred embodiment of the present invention, the polyhydric alcohol additive for enhancing adhesion between a resist pattern and an underlying film, represented by the above chemical formula, is characterized by having a molecular weight of 100 to 200. In a preferred embodiment of the present invention, the polyhydric alcohol additive for enhancing adhesion between a resist pattern and an underlying film contains, relative to the total weight of the composition, 5 to 60 wt % of a polymer resin, 1 to 5 wt % of a polyhydric alcohol additive for enhancing adhesion between a pattern and an underlying film, represented by Chemical Formulas 1 to 8, 0.05 to 10 wt % of a photoacid generator, and 0.01 to 5 wt % of an acid diffusion inhibitor, with the remainder being a solvent. In a preferred embodiment of the present invention, the polymer resin may be any commonly used photoresist resin, and is characterized in that it is at least one selected from the group consisting of phenolic polymer resins containing hydroxyl groups, represented by Chemical Formulas 9 to 13 below. [Chemical formula 9] [ka] (In the above structure, R4 is one structure selected from the structures of the following chemical formulas a to p.) <Chemical formula a> [ka] <Chemical formula b> [ka] <chemical formula c> [ka] <chemical formula d> [ka] <Chemical formula e> [ka] <Chemical formula f> [ka] <Chemical formula g>

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[0008] (In the above structure, R 10 , R 11 , R 12 is a structure selected from the structures of chemical formulas a to p. In a preferred embodiment of the present invention, the phenol polymer resin is at least one selected from the group consisting of phenol polymer resins containing hydroxyl groups, represented by Chemical Formulas 9 to 13: In a preferred embodiment of the present invention, the photoacid generator is selected from the group consisting of triphenylsulfonium triflate, triphenylsulfonium antimonate, diphenyliodonium triflate, diphenyliodonium antimonate, methoxydiphenyliodonium triflate, di-t-butyldiphenyliodonium triflate, norbornenedicarboxyimide triflate, triphenylsulfonium nonaflate, and diphenyliodonium nonaflate. niumnonaflate, methoxydiphenyliodoniumnonaflate, di-t-butyldiphenyliodoniumnonaflate, N-hydroxysuccinimidenonaflate, norbornenedicarboxyimidenonaflate, triphenylsulfoniumperfluorooctanesulfonate, diphenyliodoniumperfluorooctanesulfonate, methoxyphenyliodoniumperfluorooctanesulfonate,It is characterized by containing one or more compounds selected from the group consisting of di-t-butyldiphenyliodonium perfluorooctanesulfonate, N-hydroxysuccinimide perfluorooctanesulfonate, and norbornenedicarboximide perfluorooctanesulfonate. In a preferred embodiment of the present invention, the acid diffusion inhibitor includes at least one selected from the group consisting of dimethylamine, diethylamine, trimethylamine, triethylamine, tributylamine, dimethanolamine, diethanolamine, trimethanolamine, triethanolamine, and tributanolamine. [Effects of the Invention]

[0009] The present invention provides a photoresist composition for KrF to i-Line light sources that improves pattern profile and process margins by adding an appropriate amount of a polyhydric alcohol additive, which is effective in improving pattern profile and increasing adhesion between the pattern and underlying film. This improves pattern profile and prevents pattern collapse compared to conventional KrF to i-Line positive photoresists. That is, it is possible to secure a vertical profile, thereby improving the pattern profile, and it is possible to secure stable adhesion between the pattern and the underlying film, thereby preventing pattern collapse. DETAILED DESCRIPTION OF THE INVENTION

[0010] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention belongs. Generally, the nomenclature used herein is well known and commonly used in the art. Throughout this specification, when a part "comprises" a certain element, this does not mean that it excludes other elements, but that it may further include other elements, unless specifically stated to the contrary. The "polyhydric alcohol additive for improving adhesion between a pattern and an underlying film" referred to in the present invention means an additive that can improve adhesion by reacting with an underlying film during the thermal decomposition process during PEB (Post Exposure Bake) or HB (Hard Bake) process, which is performed after exposure to a light source of 248 nm to 365 nm. In the present invention, the term "photoresist" refers to a mixture of a polymer and a photosensitive agent, whose chemical properties change when exposed to light, and whose solubility in a specific solvent changes when exposed to light of a certain wavelength. Since there is a difference in the dissolution rate between the exposed and unexposed parts in the solvent, after a certain period of dissolution time, the undissolved parts remain, forming a pattern. The "photolithographic process" in this invention refers to a process in which, utilizing the properties of the photoresist described above, a mask engraved with a semiconductor design is placed between a light source and a photoresist film coated on a silicon wafer, and when the light source is turned on, the circuit engraved on the mask is transferred directly to the photoresist. In the present invention, "KrF" means a light source having a wavelength of 248 nm, and "i-Line" means a light source having a wavelength of 365 nm. One embodiment of the present invention provides a chemically amplified positive photoresist composition for improving pattern profile and adhesion promotion, which comprises a polyhydric alcohol additive for promoting adhesion between a pattern and an underlying film, represented by the following Chemical Formula 1: [Chemical formula 1] [ka] [Chemical formula 2] [ka] [Chemical formula 3] [ka] [Chemical formula 4] [ka] [Chemical formula 5] [ka] [Chemical formula 6] [ka] [Chemical formula 7] [ka] [Chemical formula 8] [ka]

[0011] The positive photoresist composition for improving pattern profile and enhancing adhesion, including a polyhydric alcohol additive for enhancing adhesion between a pattern and an underlying film according to the present invention, may contain, based on the total weight of the composition, 5 to 60 wt % of a polymer resin, 1 to 5 wt % of a polyhydric alcohol additive for enhancing adhesion between a pattern and an underlying film, represented by Chemical Formulas 1 to 8, 0.05 to 10 wt % of a photoacid generator, and 0.01 to 5 wt % of an acid diffusion inhibitor, with the remainder being a solvent. The polyhydric alcohol additives for improving adhesion between the pattern and the underlying film, represented by Formulas 1 to 8, are preferably included in an amount of 1 to 5 wt % based on the total weight of the composition. If the compound is used at less than 0.1 wt %, the amount of polyhydric alcohol additive for improving adhesion between the pattern and the underlying film is too small, making it impossible to ensure a vertical profile and causing problems such as pattern collapse, and is ineffective in improving adhesion. If the compound is used at more than 5 wt %, a vertical profile is ensured and there is no problem with pattern collapse, but it is undesirable because it can cause other problems such as reduced sensitivity and reduced process margins. The polymer resin may be any commonly used photoresist resin, and is characterized by being at least one selected from the group consisting of phenol polymer resins containing hydroxyl groups, represented by Chemical Formula 9 to Chemical Formula 13 below. [Chemical formula 9] [ka] (In the above structure, R4 is one structure selected from the structures of the following chemical formulas a to p.) <Chemical formula a> [ka] <Chemical formula b> [ka] <chemical formula c> [ka] <chemical formula d> [ka] <Chemical formula e> [ka] <Chemical formula f> [ka] <chemical formula g> [ka] <chemical formula h> [ka] <chemical formula i> [ka] <chemical formula j> [ka] <Chemical formula k> [ka] <chemical formula> [ka] <chemical formula m> [ka] <chemical formula n> [ka] <chemical formula o> [ka] <Chemical formula p> [ka] [Chemical formula 10] [ka] (In the above structure, R5 is one structure selected from the structures of the following chemical formulas a to p.) [Chemical formula 11] [ka] (In the above structure, R6 and R7 each represent one or more structures selected from the structures of chemical formulas a to p.) [Chemical formula 12] [ka] (In the above structure, R8 and R9 are each one structure selected from the structures of chemical formulas a to p.) [Chemical formula 13] [ka]

[0012] (In the above structure, R 10 , R 11 , R 12 is a structure selected from the structures of chemical formulas a to p. In a preferred embodiment of the present invention, the phenol polymer resin is at least one selected from the group consisting of phenol polymer resins containing hydroxyl groups, represented by Chemical Formulas 9 to 13: The polymer resin preferably comprises 5 to 60 wt % of the polymer resin based on the total weight of the composition. If the polymer resin is used in an amount less than 5 wt %, problems such as poor profile, scum, and poor etch resistance may occur, while if the polymer resin is used in an amount more than 60 wt %, problems such as poor patterning due to insufficient development may occur. The photoacid generator may be selected from the group consisting of triphenylsulfonium triflate, triphenylsulfonium antimonate, diphenyliodonium triflate, diphenyliodonium antimonate, methoxydiphenyliodonium triflate, di-t-butyldiphenyliodonium triflate, norbornenedicarboxyimide triflate, triphenylsulfonium nonaflate, diphenyliodonium nonaflate, and methoxydiphenyliodonium nonaflate. iodoniumnonaflate, di-t-butyldiphenyliodoniumnonaflate, N-hydroxysuccinimidenonaflate, norbornenedicarboxyimidenonaflate, triphenylsulfoniumperfluorooctanesulfonate, diphenyliodoniumperfluorooctanesulfonate, methoxyphenyliodoniumperfluorooctanesulfonate, di-t-butyldiphenyliodoniumperfluorooctanesulfonate,It is characterized in that it is one or more selected from the group consisting of N-hydroxysuccinimide perfluorooctanesulfonate and norbornenedicarboximide perfluorooctanesulfonate.

[0013] The photoacid generator is preferably contained in an amount of 0.05 to 10 wt % based on the total weight of the composition. If the photoacid generator is used in an amount less than 0.05 wt %, the generated acid is insufficient, resulting in a phenomenon in which the pattern slope becomes severe. If the photoacid generator is used in an amount more than 10 wt %, the photoacid generator absorbs light from the exposure source, reducing transmittance and potentially resulting in pattern defects such as an inability to define. The acid diffusion inhibitor may include at least one selected from the group consisting of dimethylamine, diethylamine, trimethylamine, triethylamine, tributylamine, dimethanolamine, diethanolamine, trimethanolamine, triethanolamine, and tributanolamine. The acid diffusion inhibitor is preferably contained in an amount of 0.01 to 5 wt % based on the total weight of the composition. If the acid diffusion inhibitor is used in an amount less than 0.01 wt %, excessive acid generation may occur, resulting in pattern defects such as pattern defects (LWR, LER) on the wall or edge of the pattern. If the acid diffusion generator is used in an amount more than 5 wt %, there is a risk that pattern formation may become impossible. Meanwhile, the thickness of the chemically amplified positive photoresist composition for improving pattern profile and enhancing adhesion containing a polyhydric alcohol additive for enhancing adhesion between the pattern and underlying film of the present invention can be 2,000 Å to 200,000 Å depending on the type and amount of solvent used, and can be used after dissolving it in 10 to 90 wt % of the weight of the solvent. Examples of the solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methylcellosolveacetate, ethylcellosolveacetate, diethyleneglycolmonomethylether, diethyleneglycolmonoethylether, propyleneglycolmonomethylether, and propylene glycol. Examples of the solvents that can be used include propylene glycol methyl ether acetate, propylene glycol propyl ether acetate, diethylene glycol dimethyl ether, ethyl lactate, toluene, xylene, methylethylketone, cyclohexanone, 2-heptanone, 3-heptanone, and 4-heptanone, and these can be used alone or in combination.

[0014] As described above, the chemically amplified positive photoresist composition for improving pattern profile and enhancing adhesion, which includes a polyhydric alcohol additive for enhancing adhesion between a pattern and an underlying film, provided by the present invention, can obtain a vertical profile depending on exposure energy by using the polyhydric alcohol additive for enhancing adhesion between a pattern and an underlying film, as represented by Chemical Formulas 1 to 8, and is effective in enhancing adhesion, thereby providing a process margin compared to existing KrF~i-Line PR. [Example] The present invention will be described in more detail below with reference to examples. It will be obvious to those skilled in the art that these examples are merely for the purpose of illustrating the present invention and should not be construed as limiting the scope of the present invention.

[0015] Example 1 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 3.5 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 118 mJ / cm 2 It was confirmed that the pattern had a positive slope with a line / space standard resolution of 3.0 μm and a pattern slope inclination angle of 84.3°, and no pattern collapse was observed. Example 2 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 5.0 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 117 mJ / cm 2 It was confirmed that a positive slope pattern with a line / space standard resolution of 2.8 μm and a pattern slope inclination angle of 84.9° was obtained, and no pattern collapse was observed.

[0016] Example 3 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 7.5 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 115 mJ / cm 2 It was confirmed that the pattern had a positive slope with a line / space standard resolution of 2.8 μm and a pattern slope inclination angle of 85.4°, and no pattern collapse was observed. Example 4 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 10.0 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 112 mJ / cm 2 It was confirmed that the pattern slope angle was 88.8° with a line / space standard resolution of 2.5 μm, and no pattern collapse was observed. Example 5 A positive KrF excimer laser photoresist composition was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 12.5 g of a polyhydric alcohol additive (in Formula 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 110 mJ / cm 2 It was confirmed that the pattern had a positive slope with a line / space standard resolution of 2.4 μm and a pattern slope inclination angle of 89.2°, and no pattern collapse was observed.

[0017] Example 6 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 13.0 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 109 mJ / cm 2 It was confirmed that a fine negative slope pattern with a line / space standard resolution of 2.4 μm and a pattern slope inclination angle of 91.9° was formed, and no pattern collapse was observed. Example 7 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 14.0 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 107 mJ / cm 2 It was confirmed that a fine negative slope pattern with a line / space standard resolution of 2.3 μm and a pattern slope inclination angle of 92.2° was formed, and no pattern collapse was observed.

[0018] Example 8 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 15.5 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 105 mJ / cm 2 It was confirmed that a fine negative slope pattern with a line / space standard resolution of 2.3 μm and a pattern slope inclination angle of 94.8° was formed, and no pattern collapse was observed. Example 9 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 17.5 g of a polyhydric alcohol additive (structure 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 104 mJ / cm 2 It was confirmed that a fine negative slope pattern with a line / space standard resolution of 2.3 μm and a pattern slope inclination angle of 95.1° was formed, and no pattern collapse was observed.

[0019] Comparative Example 1 The experiment was carried out in the same manner as in Example 1, except that no polyhydric alcohol additive was added to enhance adhesion between the pattern and the underlying film. As a result, the sensitivity was 125 mJ / cm 2 It was confirmed that it was possible to confirm patterns with a line / space resolution of 3.5 μm, but the occurrence of pattern collapses was confirmed. Comparative Example 2 A positive photoresist composition for KrF excimer laser irradiation was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 2.5 g of a polyhydric alcohol additive (in Formula 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 120 mJ / cm 2 It was confirmed that a pattern with a line / space standard resolution of 3.0 μm could be confirmed, but pattern collapse was observed. Comparative Example 3 A positive KrF excimer laser photoresist composition was prepared using 100 g of a phenolic polymer resin (in Formula 12, R8 is Formula a, R9 is Formula c, and the copolymerization molar ratios h, i, and j are 7, 2, and 1, respectively) with a weight-average molecular weight of 15,000 as the base resin, 20.0 g of a polyhydric alcohol additive (in Formula 1) with a weight-average molecular weight of 150 to enhance adhesion between the pattern and the underlying film, 4 g of triphenylsulfonium nonaflate as a photoacid generator, and 0.6 g of triethanolamine as an acid diffusion inhibitor. The composition was then spin-coated onto an aluminum-coated silicon wafer and soft-baked at 100°C for 120 seconds, resulting in a target thickness of 5 μm. After the exposure process with a 248 nm light source, a post-exposure bake (PEB) process was performed at 120°C for 90 seconds, and then a development process was performed with 2.38% tetramethylammonium hydroxide to form a pattern. As a result, the sensitivity was 101 mJ / cm 2 It was confirmed that a fine negative slope pattern with a line / space standard resolution of 2.2 μm and a pattern slope inclination angle of 96.6° was formed, and no pattern collapse was observed.

[0020] Characteristic measurements The characteristics of the chemically amplified positive photoresist compositions for improving pattern profile and increasing adhesion prepared in Examples 1 to 5 and Comparative Example 1 were measured. Resolution and adhesion were measured using a critical dimension scanning electron microscope (CD-SEM), which can observe the critical dimension of the pattern. The minimum line width (resolution) was observed and confirmed on an L / S (Line, Space) basis. Sensitivity was also confirmed by measuring the energy required to confirm the minimum line width (resolution). The results of such measurements are shown in Table 1 below. [Table 1]

[0021] As can be seen from the above and Table 1, the evaluation results of adding a polyhydric alcohol additive to enhance adhesion between the pattern and the underlying film showed that Examples 1 to 9 had improved sensitivity compared to Comparative Examples 1 and 2, and also improved resolution (minimum line width size).In addition, it was confirmed that vertical pattern slope was also improved. In the examples, when the content of the polyhydric alcohol additive for improving adhesion between the pattern and the underlying film was 1-5 wt%, it was confirmed that excellent results were obtained overall in terms of sensitivity, resolution, and pattern angle. In particular, when the content was 2.9-4.0 wt%, as in Examples 4-7, it was confirmed that excellent results were obtained overall in terms of sensitivity, resolution, and pattern angle. When observed using a critical dimension scanning electron microscope (CD-SEM), Comparative Examples 2 and 3 showed improvements in sensitivity and resolution (minimum line width size) compared to Comparative Example 1, but pattern collapse was observed in some areas. Any simple variations or modifications of the present invention can be easily implemented by a person having ordinary skill in the art, and any such variations or modifications can be considered to be included in the scope of the present invention.

Claims

1. A photoresist composition that can be exposed to a light source having a wavelength of 248 nm, A chemically amplified positive photoresist composition for improving pattern profile and adhesion, which contains 1 to 5 wt % of a polyhydric alcohol additive represented by the following Formulas 1 to 8 to achieve a vertical profile without pattern collapse. [Chemical formula 1] 【Chemical 1】 [Chemical formula 2] 【Chemistry 2】 [Chemical formula 3] 【Chemistry 3】 [Chemical formula 4] 【Chemistry 4】 [Chemical formula 5] 【Chemistry 5】 [Chemical formula 6] 【Chemistry 6】 [Chemical formula 7] 【Chemistry 7】 [Chemical formula 8] 【Chemistry 8】

2. 10. The chemically amplified positive photoresist composition for improving pattern profile and adhesion according to claim 1, wherein the photoresist composition comprises, based on a total weight of the composition, 5 to 60 wt % of a polymer resin, 1 to 5 wt % of a polyhydric alcohol additive represented by any one of Chemical Formulas 1 to 8, 0.05 to 10 wt % of a photoacid generator, and 0.01 to 5 wt % of an acid diffusion inhibitor, with the remainder being a solvent.

3. 3. The chemically amplified positive photoresist composition for improving pattern profile and adhesion according to claim 2, wherein the polymer resin is at least one selected from the group consisting of phenolic polymer resins containing a hydroxyl group, represented by the following Formulas 9 to 13: [Chemical formula 9] 【Chemistry 9】 (In the above structure, R ４ is one structure selected from the structures of the following chemical formulas a to p. <Chemical formula a> 【Chemistry 10】 <Chemical formula b> 【Chemistry 11】 <Chemical formula c> 【Chemistry 12】 <Chemical formula d> 【Chemistry 13】 <Chemical formula e> 【Chemistry 14】 <Chemical formula f> 【Chemistry 15】 <Chemical formula g> 【Chemistry 16】 <Chemical formula h> 【Chemistry 17】 <Chemical formula i> 【Chemistry 18】 <Chemical formula j> 【Chemistry 19】 <Chemical formula k> 【Chemistry 20】 <Chemical formula l> 【Chemical 21】 <Chemical formula m> 【Chemical 22】 <Chemical formula n> 【Chemical 23】 <Chemical formula o> 【Chemistry 24】 <Chemical formula p> 【Chemistry 25】 [Chemical formula 10] 【Chemical Formula 26】 (In the above structure, R ５ is one structure selected from the structures of chemical formulas a to p. [Chemical formula 11] 【Chemical 27】 (In the above structure, R ６ , R ７ is a structure selected from the structures of chemical formulas a to p. [Chemical formula 12] 【Chemical Formula 28】 (In the above structure, R ８ , R ９ is a structure selected from the structures of chemical formulas a to p. [Chemical formula 13] 【Chemical Formula 29】 (In the above structure, R １０ , R １１ , R １２ is a structure selected from the structures of chemical formulas a to p.

4. The photoacid generator is Triphenylsulfonium triflate, triphenylsulfonium antimonate, diphenyliodonium triflate, diphenyliodonium antimonate, methoxydiphenyliodonium triflate, di-t-butyl Diphenyliodonium triflate, 2,6-dinitrobenzylsulponate, pyrogalloltrisalkylsulfonate, norbornenedicarboxyimidetriflate, triphenylsulfonium nonaflate, ate), diphenyliodonium nonaflate, methoxydiphenyliodonium nonaflate, di-t-butyldiphenyliodonium nonaflate, N-hydroxysuccinimide nonaflate, norbornene dicarboximide nonaflate nedicarbonyimidenonaflate), triphenylsulfonium perfluorooctanesulfonate, diphenyliodonium perfluorooctanesulfonate, methoxyphenyliodonium perfluorooctanesulfonate,The chemically amplified positive photoresist composition for improving pattern profile and adhesion according to claim 2, comprising at least one selected from the group consisting of di-t-butyldiphenyliodonium perfluorooctanesulfonate, N-hydroxysuccinimide perfluorooctanesulfonate, and norbornenedicarboximide perfluorooctanesulfonate.

5. 3. The chemically amplified positive photoresist composition for improving pattern profile and adhesion according to claim 2, wherein the acid diffusion inhibitor comprises at least one selected from the group consisting of dimethylamine, diethylamine, trimethylamine, triethylamine, tributylamine, dimethanolamine, diethanolamine, trimethanolamine, triethanolamine, and tributanolamine.

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