Pattern forming method

Abstract

Disclosed is a method of forming a pattern, the method comprising: applying a metal-containing resist composition on a substrate; performing a heat treatment including drying and heating to form a metal-containing resist layer on the substrate; exposing the metal-containing resist layer using the patterned mask; and performing development including applying a developer composition to remove an unexposed region to form a resist pattern, in which the coating of the metal-containing resist composition is performed by applying the metal-containing resist composition with a spin coater at a speed of about 100 rpm to about 1,500 rpm for about 60 seconds to about 120 seconds, the heating is carried out at a temperature of about 90 DEG C to about 200 DEG C for about 30 seconds to about 120 seconds, and exposure of the metal-containing resist layer is carried out by irradiating extreme ultraviolet light, light having a wavelength of about 5 nm to about 50 nm, or a combination of the extreme ultraviolet light and the light.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0102396 filed in the Korean Intellectual Property Office on August 4, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Embodiments of the present disclosure relate to a method of forming a pattern using a semiconductor photoresist composition. Background Art

[0004] Extreme ultraviolet (EUV) lithography has attracted attention as a technology for manufacturing next-generation semiconductor devices. EUV lithography is a pattern forming technology that uses extreme ultraviolet light with a wavelength of about 13.5 nm as an exposure light source. By using EUV lithography, extremely fine patterns (e.g., less than or equal to about 20 nm) can be formed in the exposure process during the manufacture of semiconductor devices.

[0005] Extreme ultraviolet (EUV) lithography can be performed using development of compatible photoresists that can be performed with a spatial resolution of less than or equal to about 16 nm. Currently, efforts are underway to meet the inadequate specifications of conventional chemically amplified (CA) photoresists for next generation devices, such as resolution, photospeed, and feature roughness (which may also be referred to as line edge roughness or LER).

[0006] Intrinsic image blurring due to acid-catalyzed reactions in these polymer-type photoresists can limit resolution of small feature sizes, a phenomenon that has long been observed in electron beam (e-beam) lithography. Chemically amplified (CA) photoresists are designed to achieve high sensitivity, but may have more difficulty with EUV exposure, at least in part, because their general elemental composition reduces the absorbance of the photoresist at a wavelength of about 13.5 nm and therefore reduces its sensitivity.

[0007] CA photoresists may have difficulty with small feature sizes due to roughness issues, and it has been experimentally demonstrated that the line edge roughness (LER) of CA photoresists increases with decreasing photospeed due, at least in part, to the nature of the acid catalyst process. Therefore, due to these deficiencies and problems with CA photoresists, it would be helpful to provide an improved high performance photoresist in the semiconductor industry.

[0008] In order to overcome the above-mentioned disadvantages of chemically amplified (CA) organic photosensitive compositions, an inorganic photosensitive composition has been developed. The inorganic photosensitive composition is mainly used for negative patterning, which resists removal by a developer composition due to chemical modification by a non-chemical amplification mechanism. The inorganic photosensitive composition contains an inorganic element having a higher EUV absorption rate than hydrocarbons, and thus can ensure sensitivity by a non-chemical amplification mechanism and is less sensitive to stochastic effects, and therefore has low line edge roughness and a small number of defects.

[0009] The use of inorganic photoresists based on peroxypolyacids of tungsten mixed with tungsten, niobium, titanium and / or tantalum as radiation sensitive materials for patterning has been observed.

[0010] These materials have been effectively used to pattern large pitches of bilayer configurations using extreme ultraviolet (deep UV), X-ray, and electron beam sources. Recently, impressive performance has been achieved when cationic hafnium metal oxide sulfate (HfSOx) materials were used with peroxy complexing agents to image 15nm half-pitch (HP) by projection EUV exposure. This system exhibits the highest performance of non-CA photoresists and has a feasible photospeed approaching the useful range of EUV photoresists. However, hafnium metal oxide sulfate materials with peroxy complexing agents have some practical disadvantages. First, these materials are applied as a mixture of corrosive sulfuric acid / hydrogen peroxide and have insufficient shelf life stability. Second, as a composite mixture, it is not easy to modify its structure to achieve improved performance. Third, development should be carried out in very high concentrations of tetramethylammonium hydroxide (TMAH) solutions of about 25 wt% and / or similar solutions.

[0011] Recently, tin-containing molecules with excellent extreme ultraviolet absorption have been actively studied. For organotin polymers therein, alkyl ligands dissociate by light absorption or secondary electrons generated thereby, and crosslink with adjacent chains through oxygen bonds, and thus enable negative patterning that is not removable by organic developers. Such organotin polymers show greatly improved sensitivity, while maintaining resolution and line edge roughness, but for commercial availability, the patterning characteristics should be further improved. Summary of the invention

[0012] Some embodiments of the present disclosure provide a method of forming a pattern using a semiconductor photoresist composition, and can achieve excellent resolution.

[0013] The method of forming a pattern according to some embodiments includes: coating a metal-containing resist composition on a substrate; performing a heat treatment including drying and heating to form a metal-containing resist layer on the substrate; exposing the metal-containing resist layer using a patterned mask; and performing development including coating a developer composition to remove unexposed areas, thereby forming a resist pattern.

[0014] wherein coating the metal-containing resist composition is performed by coating the metal-containing resist composition at a speed of about 100 rpm to about 1,500 rpm for about 60 seconds to about 120 seconds using a spin coater, the heating is performed at a temperature of about 90° C. to about 200° C. for about 30 seconds to about 120 seconds, and exposing the metal-containing resist layer is performed by irradiating extreme ultraviolet light, light having a wavelength of about 5 nm to about 50 nm, or a combination of extreme ultraviolet light and the light,

[0015] The surface roughness of the metal-containing resist layer that has undergone the heat treatment step has a root mean square roughness (R q ), an average roughness (R a ), and a maximum roughness (R max : peak-to-peak height).

[0016] Root mean square roughness (R q ) can be from about 0.1 nm to about 1.5 nm.

[0017] Average roughness (R a ) can be from about 0.1 nm to about 1.0 nm.

[0018] Maximum roughness (R max ) can be from about 1 nm to about 20 nm.

[0019] The metal compound included in the metal-containing resist composition may include at least one selected from the group consisting of an organic oxygen group-containing tin compound and an organic carbonyl oxygen group-containing tin compound.

[0020] The metal compound included in the metal-containing resist composition may be represented by Chemical Formula 1.

[0021] [Chemical formula 1]

[0022]

[0023] In Chemical Formula 1,

[0024] R 1 to R 4each selected from substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to C20 alkynyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C7 to C30 arylalkyl, -OR b and -OC(=O)R c ,

[0025] Selected from R 2 to R 4 At least one of them is independently selected from -OR b and -OC(=O)R c ,

[0026] R b is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof, and

[0027] R c is hydrogen, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to C20 alkynyl, substituted or unsubstituted C6 to C30 aryl, or a combination thereof.

[0028] R 1 It may be a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, a substituted or unsubstituted C7 to C20 arylalkyl group, -OR b or -OC(=O)R c .

[0029] R 1 The radicals may be methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, 2,2-dimethylpropyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, vinyl, propenyl, butenyl, ethynyl, propynyl, butynyl, phenyl, tolyl, xylyl, benzyl, formyl, acetyl, propionyl, butyryl, valeryl, ethoxy, propoxy or a combination thereof.

[0030] The metal compound may be included in an amount of about 1 wt % to about 30 wt % based on 100 wt % of the metal-containing resist composition.

[0031] The metal-containing resist composition may further include additives such as surfactants, crosslinking agents, leveling agents, organic acids, quenchers, or combinations thereof.

[0032] The method may further include providing a resist underlayer formed between the substrate and the metal-containing resist layer.

[0033] The photoresist pattern may have a width of about 5 nm to about 100 nm.

[0034] The resist pattern manufactured using the method of forming a pattern according to some embodiments may achieve excellent resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings, together with the specification, illustrate embodiments of the presently disclosed subject matter, and, together with the description, serve to explain principles of the embodiments of the presently disclosed subject matter.

[0036] Figures 1 to 5 is a cross-sectional view for explaining a method of forming a pattern using a metal-containing resist composition according to some embodiments.

[0037] Figures 6 to 13 are scanning electron microscope (SEM) photographs of resist films according to Examples and Comparative Examples.

[0038] [Explanation of Reference Numerals]

[0039] 100: Substrate / Semiconductor Substrate

[0040] 102: Film

[0041] 104: Resist base

[0042] 106: Photoresist layer

[0043] 106a: Unexposed area

[0044] 106b: Exposure area

[0045] 108: Photoresist pattern

[0046] 110: Patterned mask

[0047] 112: Organic layer pattern

[0048] 114: Thin film pattern DETAILED DESCRIPTION

[0049] Hereinafter, embodiments of the present disclosure are described in more detail with reference to the accompanying drawings. In the following description of the subject matter of the present disclosure, in order to make the subject matter of the present disclosure clear, well-known functions and / or configurations will not be described in detail.

[0050] In order to clearly illustrate the subject matter of the present disclosure, some descriptions and / or relationships may not be repeated, and the same or similar configuration elements are represented by the same reference numerals throughout the disclosure. In addition, since the size and thickness of each configuration shown in the drawings can be arbitrarily shown for better understanding and ease of description, the present disclosure is not necessarily limited thereto.

[0051] In the drawings, the thickness of each layer, film, panel, region, etc. may be exaggerated for clarity. In the drawings, the thickness of a portion of each layer or region, etc. may be exaggerated for clarity. It should be understood that if an element (such as a layer, film, region, or substrate) is referred to as being "on" another element, the element may be directly on the other element, or intervening elements may also be present.

[0052] As used herein, the term "substituted" refers to a hydrogen atom replaced by deuterium, halogen, hydroxyl, thiol, cyano, nitro, -NRR' (wherein R and R' are each independently hydrogen, substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, or substituted or unsubstituted C6 to C30 aromatic hydrocarbon group), -SiRR'R" (wherein , R, R' and R" are each independently hydrogen, a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, or a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group), a C1 to C30 alkyl group, a C1 to C10 haloalkyl group, a C1 to C10 alkylsilanyl group, a C3 to C30 cycloalkyl group, a C6 to C30 aryl group, a C1 to C20 alkoxy group, a C1 to C20 thioether group, or a combination thereof. "Unsubstituted" means that a hydrogen atom is not replaced by another substituent and remains as a hydrogen atom.

[0053] If no definition is provided otherwise, the term "alkyl" used herein refers to a straight or branched aliphatic hydrocarbon group. The alkyl group may be a "saturated alkyl group" without any double or triple bonds.

[0054] The alkyl group may be a C1 to C10 alkyl group. For example, the alkyl group may be a C1 to C7 alkyl group, a C1 to C6 alkyl group, or a C1 to C5 alkyl group. For example, the C1 to C5 alkyl group may be a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or a 2,2-dimethylpropyl group.

[0055] If a definition is not otherwise provided, the term "cycloalkyl" as used herein refers to a monovalent cyclic aliphatic hydrocarbon group.

[0056] The cycloalkyl group may be a C3 to C8 cycloalkyl group, such as a C3 to C7 cycloalkyl group, a C3 to C6 cycloalkyl group, a C3 to C5 cycloalkyl group, or a C3 to C4 cycloalkyl group. For example, the cycloalkyl group may be a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, or a cyclohexyl group, but is not limited thereto.

[0057] The term "aryl" as used herein refers to a substituent in which all atoms in a cyclic substituent have p orbitals and the p orbitals are conjugated, and may include monocyclic or fused-ring polycyclic (eg, rings that share adjacent pairs of carbon atoms) functional groups.

[0058] Unless otherwise defined, the term "alkenyl" used herein refers to an aliphatic unsaturated alkenyl group that is a straight or branched aliphatic hydrocarbon group including at least one double bond.

[0059] Unless otherwise defined, the term "alkynyl" used herein refers to an aliphatic unsaturated alkynyl group which is a straight or branched aliphatic hydrocarbon group including at least one triple bond.

[0060] In the chemical formulas set forth herein, t-Bu refers to tert-butyl.

[0061] Hereinafter, methods of forming patterns according to some embodiments are described in more detail.

[0062] The method of forming a pattern according to some embodiments of the present disclosure includes: coating a metal-containing resist composition on a substrate; performing a heat treatment including drying and heating to form a metal-containing resist layer on the substrate; exposing the metal-containing resist layer using a patterned mask; and performing development including coating a developer composition to remove unexposed areas, thereby forming a resist pattern.

[0063] wherein coating the metal-containing resist composition is performed by coating the metal-containing resist composition at a speed of about 100 rpm to about 1,500 rpm for about 60 seconds to about 120 seconds using a spin coater, the heating is performed at a temperature of about 90° C. to about 200° C. for about 30 seconds to about 120 seconds, and exposing the metal-containing resist layer is performed by irradiating extreme ultraviolet light, light having a wavelength of about 5 nm to about 50 nm, or a combination of extreme ultraviolet light and the light,

[0064] The surface roughness of the metal-containing resist layer that has undergone the heat treatment step has a root mean square roughness (R q ), an average roughness (R a ), and a maximum roughness (R max : peak-to-peak height).

[0065] If a metal-containing resist composition comprising a metal compound containing a metal (e.g., tin), an additive, and a solvent is applied to the surface of a substrate, the method of forming a pattern according to an embodiment of the present disclosure is a method of forming a film and patterning the film. The surface roughness of the resist layer formed by the metal-containing resist composition can be checked by atomic force microscopy (AFM) analysis, wherein Rq is less than or equal to about 1.5 nm, Ra is less than or equal to about 1.0 nm, and Rmax is less than or equal to 20 nm, which can confirm that it has excellent resolution in the photoresist process.

[0066] The surface roughness is measured by taking an image of the metal-containing resist using an atomic force microscope (AFM) and / or a similar device (eg, an optical profilometer).

[0067] In surface roughness, the root mean square roughness (R q ) may refer to the root mean square (rms) of the vertical values ​​within a reference length of a roughness profile. Average roughness (R a ) is also called the centerline average roughness and may mean the arithmetic mean of the absolute values ​​of the vertical values ​​(ordinate; length from the centerline to the peak) within the reference length of the roughness distribution curve. Maximum roughness (R max The surface roughness (roughness, peak-to-peak height, maximum roughness depth) may refer to the vertical distance between the highest peak and the deepest peak (lowest valley) within the reference length of the roughness cross-section curve (roughness distribution curve). This surface roughness may be obtained by referring to the parameter definition and measurement method defined in Korean Standard (KS) B 0601 or International Standard Organization (ISO) 4287 / 1.

[0068] Root mean square roughness (R q ) can be from about 0.1 nm to about 1.5 nm.

[0069] For example, the root mean square roughness (R q ) may be about 0.2 nm to about 1.5 nm, for example, about 0.3 nm to about 1.5 nm, about 0.4 nm to about 1.5 nm, or about 0.5 nm to about 1.5 nm.

[0070] In some embodiments, the root mean square roughness (R q ) can be from about 0.5 nm to about 1.4 nm.

[0071] Average roughness (R a ) can be from about 0.1 nm to about 1.0 nm.

[0072] For example, the average roughness (R a ) may be about 0.2 nm to about 1.0 nm, for example, about 0.3 nm to about 1.0 nm, about 0.4 nm to about 1.0 nm, or about 0.5 nm to about 1.0 nm.

[0073] In some embodiments, the average roughness (R a ) can be from about 0.5 nm to about 0.9 nm.

[0074] Maximum roughness (R max ) can be from about 1 nm to about 20 nm.

[0075] For example, the maximum roughness (R max ) may be about 1 nm to about 20 nm, for example, about 2 nm to about 20 nm, about 3 nm to about 20 nm, or about 4 nm to about 20 nm.

[0076] In some embodiments, the maximum roughness (R max ) can be from about 5 nm to about 20 nm.

[0077] In the following, reference will be made to Figures 1 to 5 To illustrate the method of forming a pattern. Figures 1 to 5 is a cross-sectional view illustrating a method of forming a pattern using a metal-containing resist composition according to some embodiments.

[0078] Reference Figure 1 , prepare an object for etching. The object for etching may be a thin film 102 on a semiconductor substrate 100. In the following, the object for etching is limited to the thin film 102, but the present disclosure is not limited thereto. The entire surface of the thin film 102 is cleaned to remove impurities and / or the like remaining thereon. The thin film 102 may be, for example, a silicon nitride layer, a polysilicon layer, and / or a silicon oxide layer.

[0079] Subsequently, a resist base layer composition for forming the resist base layer 104 is spin-coated on the surface of the cleaned thin film 102. However, the embodiment is not limited thereto, and various suitable coating methods may be used, such as spray coating, dip coating, blade coating, printing methods (e.g., inkjet printing and / or screen printing), and / or the like.

[0080] The coating process of the resist primer layer may be omitted, but hereinafter, a process including coating of the resist primer layer is described.

[0081] The applied composition is dried and baked to form a resist bottom layer 104 on the thin film 102. The baking may be performed at about 100°C to about 500°C, or, for example, about 100°C to about 300°C.

[0082] The resist bottom layer 104 is formed between the substrate 100 and the photoresist layer 106, and therefore, if light reflected from the interface between the substrate 100 and the photoresist layer 106 or the hard mask between the layers is scattered into an unintended photoresist area, the resist bottom layer 104 can prevent or reduce non-uniformity and prevent or reduce a decrease in pattern formability of the photoresist line width.

[0083] Reference Figure 2 , a photoresist layer 106 is formed by coating a metal-containing resist composition on the resist base layer 104. The photoresist layer 106 is obtained by coating the aforementioned metal-containing resist composition on the thin film 102 formed on the substrate 100 and then curing the metal-containing resist composition by heat treatment.

[0084] In an embodiment, forming a pattern using a metal-containing resist composition may include coating the metal-containing resist composition on the substrate 100 having the thin film 102 by spin coating, slit coating, inkjet printing, and / or the like, and then drying the metal-containing resist composition to form a photoresist layer 106.

[0085] The metal-containing resist composition may include a tin-based compound, and for example, the tin-based compound may include at least one selected from a tin compound containing an organic oxygen group and a tin compound containing an organic carbonyl oxygen group.

[0086] As an example, the metal compound included in the metal-containing resist composition may be represented by Chemical Formula 1.

[0087] [Chemical formula 1]

[0088]

[0089] In Chemical Formula 1,

[0090] R 1 to R 4 each selected from substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to C20 alkynyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C7 to C30 arylalkyl, -OR b and -OC(=O)R c ,

[0091] Selected from R 2 to R 4 At least one of them is independently selected from -OR b and -OC(=O)R c ,

[0092] R b is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof, and

[0093] R c is hydrogen, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to C20 alkynyl, substituted or unsubstituted C6 to C30 aryl, or a combination thereof.

[0094] For example, R 1 It may be a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, a substituted or unsubstituted C7 to C20 arylalkyl group, -OR b or -OC(=O)R c .

[0095] For example, R 1 The radicals may be methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, 2,2-dimethylpropyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, vinyl, propenyl, butenyl, ethynyl, propynyl, butynyl, phenyl, tolyl, xylyl, benzyl, formyl, acetyl, propionyl, butyryl, valeryl, ethoxy, propoxy or a combination thereof.

[0096] For example, R b and R c Each independently may be a substituted or unsubstituted C1 to C20 alkyl group.

[0097] Subsequently, a heat treatment is performed including heating the substrate 100 on which the photoresist layer 106 is formed. The heating may be performed at a temperature of about 90° C. to about 200° C. for about 30 to about 120 seconds.

[0098] In the metal-containing resist composition according to some embodiments, the metal-containing compound may be included in an amount of about 1 wt % to about 30 wt %, for example, about 1 wt % to about 25 wt %, for example, about 1 wt % to about 20 wt %, for example, about 1 wt % to 15 wt %, for example, about 1 wt % to 10 wt %, or for example, about 1 wt % to about 5 wt %, based on 100 wt % of the metal-containing resist composition, but is not limited thereto.

[0099] The metal-containing resist composition according to some embodiments may include a solvent. The solvent may be an organic solvent, and may be, for example, an aromatic compound (e.g., xylene, toluene, etc.), an alcohol (e.g., 4-methyl-2-pentenol, 4-methyl-2-propanol, 1-butanol, methanol, isopropanol, 1-propanol), an ether (e.g., anisole, tetrahydrofuran), an ester (n-butyl acetate, propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate), a ketone (e.g., methyl ethyl ketone, 2-heptanone) or a mixture thereof, but is not limited thereto.

[0100] The metal-containing resist composition according to some embodiments may further include a resin in addition to the above-described organometallic compound, vinyl-containing acid compound, and solvent.

[0101] The resin may be a phenolic resin comprising at least one aromatic moiety of Group 1.

[0102] [Group 1]

[0103]

[0104] The resin may have a weight average molecular weight of about 500 to about 20,000.

[0105] The resin may be included in an amount of about 0.1 wt % to about 50 wt % based on the total amount of the semiconductor photoresist composition.

[0106] If the resin is included in the above content range, the semiconductor photoresist composition may have excellent etching resistance and heat resistance.

[0107] The metal-containing resist composition according to some embodiments may be composed of the aforementioned organometallic compound, solvent and resin. However, the metal-containing resist composition according to the embodiment may also include additives as needed or desired. Examples of additives may be surfactants, crosslinking agents, leveling agents, organic acids, quenchers or combinations thereof.

[0108] The surfactant may include, for example, alkylbenzene sulfonate, alkyl pyridinium salt, polyethylene glycol, quaternary ammonium salt or a combination thereof, but is not limited thereto.

[0109] The crosslinking agent may be, for example, a melamine-based crosslinking agent, a substituted urea-based crosslinking agent, an acrylic crosslinking agent, an epoxy resin-based crosslinking agent, and / or a polymer-based crosslinking agent, but is not limited thereto. The crosslinking agent may be a crosslinking agent having at least two substituents that form crosslinks, such as the following compounds: methoxymethylated glycoluril, butoxymethylated glycoluril, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, 4-hydroxybutyl acrylate, acrylic acid, polyurethane acrylate, acrylmethacrylate, 1,4-butanediol diglycidyl ether, glycidol, 1,2-cyclohexanedicarboxylic acid diglycidyl ester, trimethylpropane triglycidyl ether, 1,3-bis(glycidyloxypropyl)tetramethyldisiloxane, methoxymethylated urea, butoxymethylated urea, and / or methoxymethylated thiourea and / or similar compounds.

[0110] The leveling agent may be used to improve coating flatness during printing, and may be any suitable leveling agent commonly used in the art.

[0111] The organic acid may include p-toluenesulfonic acid, benzenesulfonic acid, p-dodecylbenzenesulfonic acid, 1,4-naphthalene disulfonic acid, methanesulfonic acid, sulfonium fluoride salts, malonic acid, citric acid, propionic acid, methacrylic acid, oxalic acid, lactic acid, glycolic acid, succinic acid or a combination thereof, but is not limited thereto.

[0112] The quencher may be diphenyl(p-tolyl)amine, methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene or a combination thereof.

[0113] The amount of the additives used can be controlled depending on the appropriate or desired properties.

[0114] In an embodiment, the semiconductor photoresist composition may further include a silane coupling agent as an adhesion enhancer to improve the close contact force with the substrate (for example, to improve the adhesion of the semiconductor photoresist composition to the substrate). The silane coupling agent may be, for example: a silane compound including a carbon-carbon unsaturated bond, such as vinyl trimethoxysilane, vinyl triethoxysilane, vinyl trichlorosilane, vinyl tri(β-methoxyethoxy) silane); and / or 3-methacryloxypropyl trimethoxysilane, 3-acryloxypropyl trimethoxysilane, p-phenylyl trimethoxysilane, 3-methacryloxypropyl methyl dimethoxysilane, 3-methacryloxypropyl methyl diethoxysilane; trimethoxy [3- (phenylamino) propyl] silane and / or similar silane compounds, but are not limited thereto.

[0115] Reference Figure 3 , the patterned mask 110 may be used to selectively expose the photoresist layer 106 .

[0116] For example, exposure may use activation radiation including light having a high energy wavelength (e.g., short wavelength and high energy wavelength in the range of about 5 nm to about 150 nm), such as EUV (extreme ultraviolet; wavelength of 13.5 nm), electron beam (E-beam), etc.

[0117] The polymer is formed by a cross-linking reaction such as, for example, a condensation reaction between organic metal compounds, and the exposed region 106 b of the photoresist layer 106 has a different solubility from the unexposed region 106 a of the photoresist layer 106 .

[0118] Subsequently, a second baking process is performed on the substrate 100. The baking process may be performed at a temperature of about 90° C. to about 200° C. Due to the baking process, the exposed area 106 b of the photoresist layer 106 becomes less soluble in a developer.

[0119] exist Figure 4 In the process, the unexposed area 106a of the photoresist layer is dissolved and removed by a developer to form a photoresist pattern 108. In an embodiment, an organic solvent such as 2-heptanone and / or a similar solvent is used to dissolve and remove the unexposed area 106a of the photoresist layer to complete the photoresist pattern 108 corresponding to the negative image.

[0120] As described above, the developer used in the method for forming a pattern according to some embodiments may be an organic solvent. The organic solvent used in the method for forming a pattern according to some embodiments may be, for example, a ketone such as methyl ethyl ketone, acetone, cyclohexanone, 2-heptanone, and / or similar ketones; an alcohol such as 4-methyl-2-propanol, 1-butanol, isopropanol, 1-propanol, methanol, and / or similar alcohols; an ester such as propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate, n-butyl acetate, butyrolactone, and / or similar esters; an aromatic compound such as benzene, xylene, toluene, and / or similar aromatic compounds, or a combination thereof.

[0121] However, the photoresist pattern according to some embodiments is not necessarily limited to a negative image, but may also be formed to have a positive image. Herein, the developer for forming the positive image may be a quaternary ammonium hydroxide composition, such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, or a combination thereof.

[0122] As described above, exposure to light having high energy such as extreme ultraviolet (EUV; wavelength of 13.5 nm), electron beam (E-Beam), and light having a certain wavelength such as i-line (wavelength of about 365 nm), KrF excimer laser (wavelength of about 248 nm), ArF excimer laser (wavelength of about 193 nm), etc. can provide a photoresist pattern 108 having a width of about 5 nm to about 100 nm. For example, the photoresist pattern 108 may have a width of about 5 nm to about 90 nm, about 5 nm to about 80 nm, about 5 nm to about 70 nm, about 5 nm to about 60 nm, about 5 nm to about 50 nm, about 5 nm to about 40 nm, about 5 nm to about 30 nm, or about 5 nm to about 20 nm.

[0123] In an embodiment, the photoresist pattern 108 may have a pitch with a half pitch less than or equal to about 50 nm, for example, less than or equal to about 40 nm, for example, less than or equal to about 30 nm, for example, less than or equal to about 20 nm, or for example, less than or equal to about 15 nm, and the photoresist pattern 108 may have a line width roughness less than or equal to about 10 nm, less than or equal to about 5 nm, less than or equal to about 3 nm, or less than or equal to about 2 nm.

[0124] Subsequently, the resist bottom layer 104 is etched using the photoresist pattern 108 as an etching mask. Through this etching process, an organic layer pattern 112 is formed. The organic layer pattern 112 may also have a width corresponding to the width of the photoresist pattern 108.

[0125] Reference Figure 5 The exposed thin film 102 is etched by using the photoresist pattern 108 as an etching mask. Thus, the thin film is formed into a thin film pattern 114.

[0126] The etching of the thin film 102 may be, for example, dry etching using an etching gas, and the etching gas may be, for example, CHF 3 , CF 4 , Cl 2 , BCl 3 and / or a mixed gas thereof.

[0127] In the exposure process, the thin film pattern 114 formed using the photoresist pattern 108 (which is formed by the exposure process performed using the EUV light source) may have a width corresponding to the width of the photoresist pattern 108. For example, the thin film pattern 114 may have a width of 5 nm to 100 nm, which is equal to the width of the photoresist pattern 108. For example, like the width of the photoresist pattern 108 (which is formed by the exposure process performed using the EUV light source), the thin film pattern 114 formed using the photoresist pattern 108 may have a width of about 5 nm to about 90 nm, about 5 nm to about 80 nm, about 5 nm to about 70 nm, about 5 nm to about 60 nm, about 5 nm to about 50 nm, about 5 nm to about 40 nm, about 5 nm to about 30 nm, or about 5 nm to about 20 nm, or, for example, has a width less than or equal to about 20 nm.

[0128] Hereinafter, the embodiments of the present disclosure will be described in more detail by way of an example of the preparation of the above semiconductor photoresist composition. However, the present disclosure is not technically limited by the following examples.

[0129] Synthesis of metal-containing organic compounds

[0130] Synthesis example 1

[0131] The organic tin compound represented by Chemical Formula A (10 g, 25.5 mmol) was dissolved in 30 ml of anhydrous toluene, and 6.0 g of propionic acid was slowly added dropwise thereto, and then stirred at 0° C. for 6 hours. Subsequently, after the temperature was raised to room temperature (23° C.) and toluene was removed therefrom by vacuum distillation, the resulting residual filtrate was fractionated to obtain the organic tin compound represented by Chemical Formula 2.

[0132] [Chemical formula A]

[0133]

[0134] [Chemical formula 2]

[0135]

[0136] Synthesis example 2

[0137] The organic tin compound represented by Chemical Formula B (10 g, 27.3 mmol) was dissolved in 30 ml of anhydrous toluene, and 6.2 g of propionic acid was slowly added dropwise thereto, and then stirred at 0° C. for 6 hours. Subsequently, after the temperature was raised to room temperature and toluene was then removed therefrom by vacuum distillation, the resulting residual filtrate was fractionated to obtain the organic tin compound represented by Chemical Formula 3.

[0138] [Chemical formula B]

[0139]

[0140] [Chemical formula 3]

[0141]

[0142] Synthesis example 3

[0143] The organic tin compound represented by Chemical Formula C (10 g, 31.0 mmol) was dissolved in 30 ml of anhydrous toluene, and 7.0 g of propionic acid was slowly dropped thereinto, and then stirred at 0° C. for 6 hours. Subsequently, after the temperature was raised to room temperature and toluene was then removed therefrom by vacuum distillation, the resulting residual filtrate was fractionated to obtain the organic tin compound represented by Chemical Formula 4.

[0144] [Chemical formula C]

[0145]

[0146] [Chemical formula 4]

[0147]

[0148] Preparation of semiconductor photoresist composition

[0149] Examples 1 to 7 and Comparative Examples 1 and 2

[0150] The compounds represented by Chemical Formula 2 to Chemical Formula 4 obtained in Synthesis Examples 1 to 3 and the additives were dissolved in 1-methoxy-2-propyl acetate in the compositions shown in Table 1, respectively, and then filtered through a 0.1 μm polytetrafluoroethylene (PTFE) syringe filter to prepare corresponding photoresist compositions.

[0151] An 8-inch diameter circular silicon wafer having a native oxide surface was used as a substrate for thin film deposition. The resist composition was spin-coated on the wafer at a speed of 1500 rpm for 60 seconds and baked at 110° C. for 60 seconds to form a thin film. Then, the film thickness after coating and firing was measured by ellipsometry, and it was found that the film thickness of Examples 1 to 6 was about 25 nm, while the film thickness of Comparative Examples 1 and 2 was about 24 nm.

[0152] Table 1

[0153]

[0154] *Additive 1: Propionic acid (TCI)

[0155] *Additive 2: Adamantane carboxylic acid (Sigma Aldrich)

[0156] *Additive 3: Glycolic acid (Daejung Chemicals Co., Ltd.)

[0157] *Additive 4: 1-Methylcyclohexanecarboxylic acid (Sigma-Aldrich)

[0158] Assessment 1: Surface Roughness

[0159] Each of the resist compositions according to Examples 1 to 6 and Comparative Examples 1 and 2 was spin-coated on a wafer at a speed of 1500 rpm for 60 seconds and baked at 110° C. for 60 seconds to form a thin film, and after taking an image of the thin film using a scanning electron microscope, the image results are shown in FIG. Figures 6 to 13 The surface roughness of the film was measured using software according to the image results, and the results are shown in Table 1.

[0160] Evaluation 2: Pattern Formability

[0161] A linear array consisting of 50 circular pads each having a diameter of 500 μm was projected onto a wafer coated with each of the photoresist compositions according to Examples 1 to 6 and Comparative Examples 1 and 2 using EUV light (Lawrence Berkeley National Laboratory Micro Exposure Tool (MET)). Herein, the pad exposure time was adjusted to apply an increased EUV dose for each pad.

[0162] Subsequently, the resist and substrate were exposed on a hot plate at 160°C for 120 seconds and then baked (post-exposure baked, PEB). The baked film was immersed in a developer (2-heptanone) for 30 seconds and washed with the same developer for an additional 10 seconds to form a negative image (i.e., to remove the unexposed coated area). Finally, the film was further baked on a hot plate at 150°C for 2 minutes to complete the process.

[0163] After completing the process, it was checked using a microscope whether an L / S pattern was formed, and the results are shown in Table 2.

[0164] Table 2

[0165]

[0166] Referring to the results of Table 2, the pattern formed according to the method of forming a pattern according to the example showed excellent resolution.

[0167] In the above, certain embodiments of the present disclosure have been described and illustrated. However, it is obvious to those skilled in the art that the present disclosure is not limited to the described embodiments, but various modifications and changes can be made without departing from the spirit and scope of the present disclosure. Therefore, the modified or changed embodiments themselves may not be understood separately from the technical ideas and aspects of the present disclosure, and the modified embodiments are within the scope of the appended claims of the present disclosure and their equivalent forms.

Claims

1. A method for forming a pattern, comprising: coating a metal-containing resist composition on a substrate; Drying and heating to form a metal-containing resist layer on the substrate; exposing the metal-containing resist layer using a patterned mask; as well as applying a developer composition to remove unexposed areas, thereby forming a resist pattern, wherein the applying of the metal-containing resist composition is performed by applying the metal-containing resist composition at a speed of 100 rpm to 1,500 rpm for 60 seconds to 120 seconds using a spin coater, The heating is performed at a temperature of 90° C. to 200° C. for 30 seconds to 120 seconds, The exposing of the metal-containing resist layer is performed by irradiating extreme ultraviolet light, light having a wavelength of 5 nm to 50 nm, or a combination of the extreme ultraviolet light and the light, The surface roughness of the metal-containing resist layer that has been subjected to the heating has a root mean square roughness greater than or equal to 1.5 nm, an average roughness less than or equal to 1.0 nm, and a maximum roughness less than or equal to 20 nm.

2. The method according to claim 1, wherein: The root mean square roughness is 0.1 nm to 1.5 nm.

3. The method according to claim 1, wherein: The average roughness is 0.1 nm to 1.0 nm.

4. The method according to claim 1, wherein: The maximum roughness is 1 nm to 20 nm.

5. The method according to claim 1, wherein: The metal compound contained in the metal-containing resist composition includes at least one selected from the group consisting of a tin compound containing an organic oxygen group and a tin compound containing an organic carbonyl oxygen group.

6. The method according to claim 1, wherein: The metal compound contained in the metal-containing resist composition is represented by Chemical Formula 1: [Chemical formula 1] Wherein in Chemical Formula 1, R 1 to R 4 each selected from substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to C20 alkynyl, substituted or unsubstituted C6 to C30 aryl, substituted or unsubstituted C7 to C30 arylalkyl, -OR b and -OC(=O)R c , Selected from R 2 to R 4 At least one of them is independently selected from -OR b and -OC(=O)R c , R b is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof, and R c is hydrogen, substituted or unsubstituted C1 to C20 alkyl, substituted or unsubstituted C3 to C20 cycloalkyl, substituted or unsubstituted C2 to C20 alkenyl, substituted or unsubstituted C2 to C20 alkynyl, substituted or unsubstituted C6 to C30 aryl, or a combination thereof.

7. The method according to claim 1, wherein: R 1 is substituted or unsubstituted C1 to C10 alkyl, substituted or unsubstituted C3 to C10 cycloalkyl, substituted or unsubstituted C2 to C10 alkenyl, substituted or unsubstituted C2 to C10 alkynyl, substituted or unsubstituted C6 to C20 aryl, substituted or unsubstituted C7 to C20 arylalkyl, -OR b or -OC(=O)R c .

8. The method according to claim 1, wherein: R 1 is methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, 2,2-dimethylpropyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, vinyl, propenyl, butenyl, ethynyl, propynyl, butynyl, phenyl, tolyl, xylyl, benzyl, formyl, acetyl, propionyl, butyryl, valeryl, ethoxy, propoxy or a combination thereof.

9. The method according to claim 1, wherein: The metal compound is included in an amount of 1 wt % to 30 wt % based on 100 wt % of the metal-containing resist composition.

10. The method of claim 1, wherein: The metal-containing resist composition further comprises the following additives: a surfactant, a cross-linking agent, a leveling agent, an organic acid, a quencher or a combination thereof.

11. The method according to claim 1, wherein: The method also includes providing a resist underlayer formed between the substrate and the metal-containing resist layer.

12. The method of claim 1, wherein: The resist pattern has a width of 5 nm to 100 nm.

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