Antireflective compositions, antireflective films, patterning methods, patterned substrates, semiconductor devices, and methods of making the same

Abstract

This application provides an anti-reflective composition, an anti-reflective film, a patterning method, a patterned substrate, a semiconductor device, and a method for fabricating the same. Applying the film formed by this anti-reflective composition to the fabrication process of a semiconductor device can effectively reduce the reflection and diffraction of light sources by components such as the substrate beneath the photosensitive material film, and can further reduce the linewidth roughness of the patterned film and improve the white edge phenomenon of the patterned film.

Description

Technical Field

[0001] This application relates to the field of semiconductor device fabrication, specifically to antireflective compositions, antireflective films, patterning methods, patterned substrates, semiconductor devices, and methods for fabricating the same. Background Technology

[0002] With the rapid development of semiconductor integrated circuits in recent years, the requirements for the critical dimensions of chips have been continuously shrinking. Patterning processes typically involve forming a photosensitive material film on a substrate, allowing an exposure light source to shine through a mask with a predetermined pattern onto the photosensitive material film, followed by selective dissolution of the photosensitive material film by development to form a patterned film, and then etching the substrate with the patterned film to transfer the pattern. However, the substrate beneath the photosensitive material film can reflect the light source or cause diffraction, making it difficult to control the critical dimensions. To reduce the damage to the patterned film caused by reflected and diffracted light, an anti-reflective film layer can be introduced between the photosensitive material film and the substrate. In recent years, the industry has commonly used organic resin-based anti-reflective films, but as the critical dimensions of chips continue to shrink, the performance of current anti-reflective films still needs to be improved to further enhance the pattern fineness of the photosensitive material film. Summary of the Invention

[0003] Therefore, embodiments of this application provide an antireflective composition, an antireflective film, a patterning method, a patterned substrate, a semiconductor device, and a method for fabricating the same. Applying the film formed by this antireflective composition to the fabrication process of a semiconductor device can not only effectively reduce the reflection and diffraction of the light source by components such as the substrate beneath the photosensitive material film, but also further reduce the linewidth roughness of the patterned film and improve the foot phenomenon of the patterned film.

[0004] The first aspect of this application provides an antireflective composition, comprising a resin, an additive, and a solvent; the resin comprises one or more of polyhydroxystyrene resins, polyester resins, and polyacrylate resins; the polyhydroxystyrene resin comprises structural units derived from hydroxystyrene, and both the polyester resin and the polyacrylate resin have hydroxyl-containing structural units.

[0005] The additive includes a first additive, and / or the additive includes a second additive;

[0006] The first additive includes one or more of pyrazole, pyrrole, tetrahydropyrrole, pyrimidine, purine, adenine, and 6-hydroxypurine;

[0007] The second additive includes one or more of ammonia, substituted or unsubstituted aniline, substituted or unsubstituted naphthylamine, and substituted or unsubstituted alkylamine;

[0008] The mass of the additive is less than or equal to 0.05% of the total mass of the resin.

[0009] When the coating formed by the above-mentioned antireflective composition is placed at the bottom of the photosensitive material layer, the line width roughness (LWR) of the patterned film can be effectively reduced under the synergistic effect of the resin and a specific amount of additive, and the white edge phenomenon of the patterned film can be improved. This is beneficial to optimizing the patterning effect in the semiconductor device manufacturing process and to the preparation and application of high-performance semiconductor devices.

[0010] In some embodiments of this application, the sum of the mass of the structural units derived from hydroxyl-containing styrene and the hydroxyl-containing structural units accounts for 10%-50% of the total mass of the resin. This is more conducive to reducing the LWR of the pattern and minimizing or even eliminating white edges on the pattern.

[0011] In some embodiments of this application, the additive accounts for 0.005%-0.05% of the total mass of the resin. This is more conducive to reducing the LWR of the pattern formed after exposure of the photosensitive material film, and reducing or even eliminating the white edge phenomenon of the pattern.

[0012] In some embodiments of this application, the resin accounts for 0.4%-5% of the mass of the antireflective composition. This results in good coating properties of the antireflective composition, which is beneficial for forming an antireflective film of suitable thickness and good uniformity.

[0013] In some embodiments of this application, the solvent includes one or more of propylene glycol methyl ether acetate, 2-ethyl-1,3-propanediol, 1,4-butyrolactone, methyl 2-hydroxyisobutyrate, propylene glycol methyl ether, ethyl lactate, and cyclohexanone; the solvent accounts for 93.5%-99.5% of the mass of the antireflective composition. The above-mentioned solvents have good compatibility with the resin used in the antireflective composition of this application, as well as the first additive, second additive, and other components, and can form a homogeneous and stable solution, which is beneficial to the application of the antireflective composition.

[0014] In some embodiments of this application, a crosslinking agent is also included; the crosslinking agent accounts for 0.05%-1% of the mass of the antireflective composition. The crosslinking agent is used to cause the resin to undergo a crosslinking reaction.

[0015] In some embodiments of this application, an acid-providing compound is also included; the acid-providing compound comprises 0.01%-0.5% of the mass of the antireflective composition. This catalyzes the reaction between the crosslinking agent and the resin, and also reduces the risk of acid generated by the acid-providing compound diffusing into the photosensitive film in subsequent processes.

[0016] In some embodiments of this application, the additive includes the first additive and the second additive. The synergistic effect of the first and second additives further helps to reduce the LWR of the pattern formed by the photosensitive material film and improves the white edge phenomenon.

[0017] In some embodiments of this application, the mass ratio of the first additive to the second additive is 1:9 to 9:1. This is more conducive to reducing the LWR of the pattern formed by the photosensitive material film, and at the same time, it is conducive to improving or even eliminating the white edge phenomenon of the patterned film.

[0018] A second aspect of this application provides an antireflective film comprising a solid molded form of the antireflective composition provided in the first aspect of this application.

[0019] In the patterning process, placing the anti-reflective film below the photosensitive material film can effectively reduce the line width roughness of the pattern formed after exposure and development of the photosensitive material film, and can also effectively improve or eliminate the white edge phenomenon of the patterned film, thereby facilitating the fabrication of highly integrated semiconductor devices.

[0020] A third aspect of this application provides a patterning process, including:

[0021] The aforementioned antireflective composition provided in the embodiments of this application is coated onto a substrate to form an antireflective film on the substrate;

[0022] A photosensitive material film is formed on the surface of the anti-reflective film;

[0023] A photosensitive material film is exposed and developed using a photomask to form a patterned film on a substrate;

[0024] Etching yields a patterned substrate.

[0025] A fourth aspect of this application provides a patterned substrate, which is fabricated using the patterning process provided in this application. The critical dimensions and linewidth roughness of the pattern on this patterned substrate can reach industry-leading levels, and it can be used to provide high-precision, high-reliability semiconductor devices, such as high-precision, high-reliability integrated circuits.

[0026] A fifth aspect of this application provides a semiconductor device, which includes a patterned substrate and a functional layer disposed on the patterned substrate, as provided in this application embodiment.

[0027] Because it is fabricated using the patterned substrate provided in the embodiments of this application, the semiconductor device provided in the embodiments of this application can have both high precision and high reliability.

[0028] In this application embodiment, there are no special limitations on the structure of the semiconductor device. Those skilled in the art can design it based on actual application needs and prepare it using the acid-sensitive resin, photosensitive composition, patterned film, or patterned substrate provided in this application embodiment. In this application embodiment, the semiconductor device includes, but is not limited to, integrated circuit devices such as chips. It is understood that the semiconductor device provided in this application embodiment also includes a functional layer, which may include any structure applicable to the semiconductor device, such as metal wiring, active devices, passive devices, etc.

[0029] The sixth aspect of this application provides a method for fabricating a semiconductor device, comprising:

[0030] The anti-reflective composition provided in the embodiments of this application is coated on a substrate to form an anti-reflective film on the substrate;

[0031] A photosensitive material film is formed on the surface of the anti-reflective film;

[0032] A photosensitive material film is exposed and developed using a photomask to form a patterned film on a substrate;

[0033] Etching yields a patterned substrate;

[0034] A functional layer is fabricated to obtain a semiconductor device.

[0035] The above preparation method is suitable for large-scale industrial production and can produce high-precision, high-reliability semiconductor devices. Attached Figure Description

[0036] Figure 1 A scanning electron microscope (SEM) image of the patterned film obtained by exposure performance test 1 using the anti-reflection composition of Example 1 of this application;

[0037] Figure 2 SEM image of the patterned film obtained by exposure performance test 1 using the anti-reflection composition of Example 2 of this application;

[0038] Figure 3 SEM image of the patterned film obtained by exposure performance test 1 using the anti-reflection composition of Example 3 of this application;

[0039] Figure 4 SEM image of the patterned film obtained by exposure performance test 1 using the antireflective composition of Comparative Example 1;

[0040] Figure 5 SEM image of the patterned film obtained by exposure performance test 2 using the anti-reflective composition of Example 4. Detailed Implementation

[0041] As the critical dimensions of semiconductor integrated circuits have been shrinking in recent years, the requirements for precision in each stage of semiconductor manufacturing processes have been continuously increasing. Patterning is one of the key processes in semiconductor manufacturing. It typically involves forming a photosensitive material film on a substrate, allowing an exposure light source to shine through a mask with a predetermined pattern onto the photosensitive material film, then selectively dissolving the photosensitive material film through development to form a patterned film, and finally etching the substrate with the patterned film to transfer the pattern. The precision of the pattern, to a certain extent, determines the lower limit of the chip's precision. During the exposure process, the substrate (e.g., a silicon wafer) beneath the photosensitive material film reflects the light source. The reflected light interferes with the incident light, creating a standing wave effect and multiple exposures within the photosensitive material film. This leads to uncontrollable critical dimensions of the pattern, impairing pattern clarity and resolution, and compromising etching precision. Furthermore, the patterned film also generates footprints, which appear as white edges on the edges of the pattern in a top-view SEM image of the patterned film. The more pronounced the white edges, the more severe the footprint problem. To reduce the damage of reflected and diffracted light to patterned films, an anti-reflective coating can be introduced between the photosensitive material film and the substrate, or between the photosensitive material film and other underlying layers. In recent years, the industry has commonly used organic resin-based anti-reflective compositions to form bottom anti-reflective coatings, but their performance still needs improvement. The anti-reflective performance of commonly used bottom anti-reflective coatings mainly relies on resins with light-absorbing capabilities, thereby reducing the reflectivity of the substrate.

[0042] This application provides an antireflective composition comprising a resin, an additive, and a solvent. The resin includes one or more of polyhydroxystyrene (PHS) resins, polyester resins, and polyacrylate resins. The PHS resin includes structural units derived from hydroxystyrene, and the polyester resin and polyacrylate resin both have hydroxyl-containing structural units. The resin has the ability to absorb light with wavelengths of 100 nm to 400 nm, and the film formed by it can effectively reduce the reflection of the substrate from the exposure light source. The PHS resin includes modified or unmodified PHS, wherein unmodified PHS can be, for example, a homopolymer of hydroxystyrene; modified PHS includes copolymers of hydroxystyrene with other monomers, and / or homopolymers or copolymers of hydroxystyrene modified with other groups or compounds, and the other monomers copolymerized with hydroxystyrene can be, but are not limited to, styrene. In this application embodiment, the PHS resin includes structural units derived from hydroxystyrene, wherein the structural units derived from hydroxystyrene include structural units obtained by breaking the carbon-carbon double bonds of the vinyl groups in hydroxystyrene and undergoing addition polymerization. Polyester resins include resins whose main chain contains structural units obtained by polycondensation of polyols and polyacids; resins that contain another type of polyester obtained by transesterification of polyols, polyacids, polyesters and other polyesters; and resins that contain structural units obtained by ring-opening of polyols or polyacids with epoxy monomers. That is, polyester resins include modified or unmodified polyester resins. Polyacrylate resins include resins whose main chain contains structural units derived from substituted or unsubstituted acrylates. That is, polyacrylate resins include modified or modified polyacrylates. It can be understood that polymethyl methacrylate resins also belong to polyacrylate resins.

[0043] In this application, the hydroxyl-containing structural unit includes a structural unit with exposed hydroxyl groups. In polyacrylate resins, the hydroxyl-containing structural unit can be, for example, a structural unit derived from an acrylate with exposed hydroxyl groups in its substituents, obtained by breaking and adding the carbon-carbon double bonds of the aforementioned acrylate. Specifically, the hydroxyl-containing acrylate can be represented as... The structural unit containing a hydroxyl group is represented as follows: Wherein, R1 has exposed hydroxyl groups; in some specific embodiments, the hydroxyl groups in R1 of the acrylate having hydroxyl groups are bonded by carbon atoms to the acrylate groups ( * indicates a linking site. Specifically, R1 can be, for example, a substituted alkyl group, a substituted cycloalkyl group, a substituted alkenyl group, a substituted cycloalkenyl group, or a substituted lactone group; the substituents in the substituted alkyl group, substituted cycloalkyl group, substituted alkenyl group, substituted cycloalkenyl group, or substituted lactone group include hydroxyl groups (-OH); this application does not limit the linking position of the hydroxyl group on the above-mentioned substituted group, any position that can be replaced by a hydroxyl group is acceptable. In the embodiments of this application, one R1 may include one or more hydroxyl groups, and the number of hydroxyl groups can be, for example, 1, 2, 3, 4, etc., as long as it can be prepared. In some specific embodiments, the number of hydroxyl groups in one R1 is 1. Of course, the substituents in the above-mentioned R1 may also include other substituent groups, such as fluorine atoms. It is understood that polyacrylate resins may contain multiple hydroxyl-containing structural units. In this case, the multiple hydroxyl-containing structural units may be the same or different; for example, the R1 of multiple hydroxyl-containing structural units may all be It can also be that R1 of a portion of the hydroxyl-containing structural units is... The other part of the hydroxyl-containing structural units This application does not impose any limitations on this; all * indicate connection positions. In this application, R2 includes, but is not limited to, hydrogen atoms, substituted or unsubstituted C1-C4 alkyl groups, etc.

[0044] In polyester resins, hydroxyl-containing structural units refer to structural units with exposed hydroxyl groups; wherein, the hydroxyl groups can be located on the side chain or on the main chain of the polyester resin. In some embodiments of this application, in polyester resins, hydroxyl-containing structural units can be, for example, In polyester resins, the number of hydroxyl groups in a hydroxyl-containing structural unit can be, for example, 1, 2, 3, or 4; in some specific embodiments, in polyester resins, a hydroxyl-containing structural unit contains 1 hydroxyl group.

[0045] Additives include a first additive and / or a second additive;

[0046] The first additive includes one or more of pyrazole, pyrrole, tetrahydropyrrole, pyrimidine, purine, adenine, and 6-hydroxypurine; the first additive can synergistically interact with hydroxyl-containing structural units in the resin topology and structural units derived from hydroxystyrene, and will not volatilize after treatment such as baking in semiconductor manufacturing processes.

[0047] The second additive includes one or more of ammonia, substituted or unsubstituted aniline, substituted or unsubstituted naphthylamine, and substituted or unsubstituted alkylamine; the second additive has a certain degree of stability. In the embodiments of this application, aniline can be, for example, aniline or diphenylamine; substituted aniline can be, for example, N-methylaniline; substituted naphthylamine can be, for example, N-methylnaphthylamine; alkylamine can be, for example, R3-NH2, R4-NH-R5, wherein R3, R4, and R5 are each independently C2-C8 alkyl; the alkyl group can be, for example, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, etc.; alkylamine can be, for example, one or more of diethylamine, triethylamine, di-n-propylamine, n-butylamine, etc. A substituted alkylamine can be, for example, ethylenediamine.

[0048] The mass of the additive is less than or equal to 0.05% of the total mass of the resin.

[0049] In the antireflective composition, the resin exhibits high absorbance for light sources with wavelengths of 193 nm or 248 nm, which is particularly beneficial for reducing the reflection of the substrate or the bottom layer of the photosensitive material film from these light sources, thereby improving the fineness of the pattern after development. Specifically, when the coating formed by the antireflective composition is placed at the bottom of the photosensitive material layer, the synergistic effect of the resin and a specific amount of designated additives can effectively reduce the line width roughness (LWR) of the resulting patterned film, improve the white edge phenomenon of the patterned film, and thus optimize the patterning effect in semiconductor device manufacturing processes, facilitating the fabrication and application of high-performance semiconductor devices.

[0050] Specifically, the percentage of additives relative to the total mass of resin can be, for example, 0.05%, 0.048%, 0.046%, 0.045%, 0.042%, 0.04%, 0.038%, 0.036%, 0.035%, 0.032%, 0.03%, 0.028%, 0.026%, 0.025%, 0.022%, 0.02%, 0.018%, 0.016%, 0.015%, 0.012%, 0.01%, 0.009%, 0.008%, 0.007%, 0.006%, 0.005%, 0.0045%, 0.004%, 0.0035%, 0.003%, 0.002%, 0.0025%, 0.001%, etc. If the additives account for too large a mass percentage of the resin (>0.05%), the upper photosensitive material will not be fully exposed in subsequent processes, and the photosensitive material will be difficult to remove after development.

[0051] In this application, the presence of resin is tested using methods such as nuclear magnetic resonance (NMR) and mass spectrometry (MS / MS); the presence of hydroxyl-containing structural units and structural units derived from hydroxyl styrene is characterized using NMR, MS / MS, and infrared spectroscopy; and the presence of additives is characterized using methods such as NMR and MS / MS.

[0052] In the embodiments of this application, including but not limited to using high performance liquid chromatography (HPLC) to characterize the mass ratio of additives to resins.

[0053] In some embodiments of this application, the additive accounts for 0.005%-0.05% of the total mass of the resin. By controlling the mass ratio of the two within the above range, when the antireflective composition is applied in the patterning process, it is more conducive to reducing the LWR of the pattern formed after the photosensitive material film is exposed, and reducing or even eliminating the white edge phenomenon of the pattern; for example, the LWR of a pattern with a resolution of 190nm is ≤3.7nm. Specifically, based on the total mass of the resin in the antireflective composition, the mass percentage of the additive can be, for example, 0.05%, 0.048%, 0.046%, 0.045%, 0.042%, 0.04%, 0.038%, 0.036%, 0.035%, 0.032%, 0.03%, 0.028%, 0.026%, 0.025%, 0.022%, 0.02%, 0.018%, 0.016%, 0.015%, 0.012%, 0.01%, 0.009%, 0.008%, 0.007%, 0.006%, or 0.005%.

[0054] In some embodiments of this application, the sum of the mass of the structural units derived from hydroxyl-containing styrene and the hydroxyl-containing structural units accounts for 10%-50% of the total mass of the resin. Specifically, the hydroxyl-containing structural units refer specifically to hydroxyl-containing structural units in polyacrylate resins and polyester resins. Thus, the antireflective composition exhibits good film-forming properties, facilitating the formation of a uniform film layer and the coating and molding of photosensitive material films. More importantly, the antireflective film formed has high absorbance for the aforementioned specific wavelengths of light, further reducing the LWR of the pattern and minimizing or even eliminating white edges on the pattern. Specifically, based on the total mass of the resin in the antireflective composition, the mass percentage of the sum of the masses of structural units derived from hydroxyl-containing styrene and structural units containing hydroxyl groups can be, for example, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, etc. Specifically, it may contain the following: 1) The resin is a copolymer of hydroxystyrene and other monomers, in which case the structural units derived from hydroxystyrene account for 10%-50% of the resin mass; 2) The resin is a polyacrylic resin and / or a polyester resin, in which case the hydroxyl-containing structural units account for 10%-50% of the resin mass; 3) The resin includes a copolymer of hydroxystyrene and other monomers, as well as polyacrylic resins and / or polyester resins, in which case the sum of the mass of the hydroxyl-containing structural units and the structural units derived from hydroxystyrene accounts for 10%-50% of the total mass of the resin.

[0055] In this application, the embodiments include, but are not limited to, using nuclear magnetic resonance spectroscopy (NMR) carbon spectroscopy to test the structural units derived from hydroxyl-containing styrene and the mass percentage of the hydroxyl-containing structural units in the resin.

[0056] In some embodiments of this application, the resin accounts for 0.4%-5% of the mass of the antireflective composition. This results in good coating properties of the antireflective composition, which is beneficial for forming an antireflective film of suitable thickness and good uniformity. Specifically, the mass percentage of the resin in the antireflective composition can be, for example, 0.4%, 0.5%, 0.6%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.

[0057] In the embodiments of this application, the process includes, but is not limited to, treating the antireflective composition by freeze-drying to remove the solvent, dissolving the solid substance obtained after freeze-drying in a certain amount of deuterated reagent and performing NMR testing, recalculating the peaks of the NMR test results, and then calculating and determining the content of resin in the antireflective composition.

[0058] In some embodiments of this application, the solvent for the antireflective composition includes one or more of propylene glycol methyl ether acetate, 2-ethyl-1,3-propanediol, 1,4-butyrolactone, methyl 2-hydroxyisobutyrate, propylene glycol methyl ether, ethyl lactate, and cyclohexanone. These solvents exhibit good compatibility with the resins used in the antireflective composition of this application, as well as the first and second additives, forming a homogeneous and stable solution, which is beneficial for the application of the antireflective composition. In some embodiments of this application, the solvent accounts for 93.5%-99.5% of the mass of the antireflective composition. Specifically, the mass percentage of the solvent in the antireflective composition can be, for example, 93.5%, 94%, 95%, 96%, 97%, 98%, 99%, 99.5%, etc.

[0059] In patterning processes, an antireflective composition is typically coated onto a substrate, baked, and the solvent removed to obtain an antireflective film. However, to facilitate the subsequent formation of a photosensitive film and to prevent the resin in the antireflective film from being dissolved by the solvent of the photosensitive material, the resin in the antireflective composition needs to be cross-linked during the baking process to form an antireflective film with certain mechanical properties. To induce cross-linking of the resin, the antireflective composition also includes a cross-linking agent, which is used to induce a cross-linking reaction in the resin. The cross-linking agent needs to be determined based on the selected resin, and may include, but is not limited to, melamine, glycourea, isocyanurate, benzoguanidine-based substances, and urea-based substances. In some specific embodiments, the cross-linking agent may be one or more of N,N-dimethoxymethyl-melamine, tetramethoxymethylglycourea, and tris(2-hydroxyethyl)isocyanurate.

[0060] In some embodiments of this application, in order to control the degree of crosslinking of the resin within a suitable range—ensuring both sufficient mechanical strength and ease of removal from the substrate in subsequent processes—the mass percentage of the crosslinking agent in the antireflective composition is controlled to be 0.1%-1%. Specifically, the mass percentage of the crosslinking agent in the antireflective composition can be, for example, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%.

[0061] In the embodiments of this application, the process includes, but is not limited to, treating the antireflective composition by freeze-drying to remove the solvent, dissolving the solid material obtained after freeze-drying in a quantitative amount of deuterated reagent and performing NMR testing, recalculating the peaks of the NMR test results, and then calculating and determining the content of the crosslinking agent in the antireflective composition.

[0062] In some cases, the antireflective composition also includes a thermogenic acid-producing agent to initiate or catalyze the crosslinking reaction between the crosslinking agent and the resin. After the antireflective composition is coated onto the substrate, during baking, the thermogenic acid-producing agent generates acid upon heating, thereby initiating the reaction between the resin and the crosslinking agent to form an antireflective film insoluble in the solvent used for photosensitive materials. To fully initiate and catalyze the reaction between the crosslinking agent and the resin, in some embodiments of this application, the mass percentage of the thermogenic acid-producing agent in the antireflective composition is controlled to be 0.05%-0.5%; this also reduces the risk of unreacted acid from the thermogenic acid-producing agent diffusing into the photosensitive film in subsequent processes. Specifically, the mass percentage of the thermogenic acid-producing agent in the antireflective composition can be, for example, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, or 0.5%.

[0063] In some embodiments of this application, the compounds that can provide acids include, but are not limited to, one or more of acid compounds and acid-generating agents. Specifically, the acid compounds may include, for example, one or more of sulfonic acid compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, and dodecylbenzenesulfonic acid, and / or one or more of carboxylic acid compounds such as salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, and hydroxybenzoic acid, but are not limited thereto. Acid-generating agents may include one or more of the following: sulfonate acid-generating agents such as triethylamine dodecyl sulfonate, amine p-toluenesulfonate, amine trifluoromethanesulfonate, and pyridinium p-toluenesulfonate; iodonium salt acid-generating agents such as diphenylhexafluorophosphate iodonium and bis(4-tert-butylphenyl)trifluoromethanesulfonate iodonium; and sulfonium triphenyltrifluoromethanesulfonate; and / or one or more of the following acid-generating agents that are generated by light or heat: cyclohexyltrifluoromethanesulfonate, methyl trifluoromethanesulfonate, cyclohexyl 2,4,6-triisopropylbenzenesulfonate, and 2-nitrobenzyl p-toluenesulfonate.

[0064] In the embodiments of this application, the process includes, but is not limited to, treating the antireflective composition by freeze-drying to remove the solvent, dissolving the solid substance obtained after freeze-drying in a quantitative amount of deuterated reagent and performing NMR testing, recalculating the peaks of the NMR test results, and then calculating and determining the content of the thermally induced acid-producing agent in the antireflective composition.

[0065] In some embodiments of this application, the additives include a first additive and a second additive. The simultaneous introduction of both the first and second additives makes it easier to adjust the pH value of the antireflective composition and the film formed by its coating, and to adjust the acidity or alkalinity of the interface between the antireflective coating and the photosensitive material film. Furthermore, the combined effect of the second and first additives, along with the resin, further helps to reduce the LWR of the pattern formed by the photosensitive material film and improve the white edge phenomenon.

[0066] In some embodiments of this application, the mass ratio of the second additive to the first additive is 1:9 to 9:1; that is, the mass ratio of the second additive to the first additive is 1:0.11 to 1:9. In some specific embodiments, the mass ratio of the second additive to the first additive is 3:7 to 7:3; that is, the mass ratio of the second additive to the first additive is 1:0.428 to 1:2.33. This is more conducive to reducing the LWR of the pattern formed by the photosensitive material film, and at the same time, it is conducive to improving or even eliminating the white edge phenomenon of the patterned film. In addition, controlling the amount of both within the above range is conducive to controlling the pH of the antireflective composition, or in other words, it can broaden the tolerance of the effect of the amount of the first additive and the second additive in the antireflective composition on the pH value of the composition, which is beneficial to the preparation of the antireflective composition. In this application, the mass ratio of the second additive to the first additive can be, for example, 1:9, 1:8, 1:7, 1:6, 1:5, 1:4, 1:3, 1:2, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 1:0.43, 1:0.45, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2.1, 1:2.2, or 1:2.3.

[0067] In this embodiment, the antireflective composition may further include other additives, such as leveling agents, defoamers, and plasticizers, which helps to improve the coating performance of the antireflective composition. Those skilled in the art can determine the amount of the above-mentioned additives added to the antireflective composition according to actual production needs.

[0068] This application also provides an antireflective film, which includes a solid molded article of the antireflective composition provided in this application. In some embodiments of this application, the antireflective film includes a cross-linked resin, and a first additive and / or a second additive. In some embodiments of this application, the thickness of the antireflective film can be, for example, 10 nm to 300 nm. This application does not limit this, and those skilled in the art can determine the thickness of the antireflective film according to actual production needs.

[0069] The anti-reflective film provided in this application embodiment can be removed using a dry etching process.

[0070] In some embodiments of this application, the preparation of the antireflective film includes:

[0071] An antireflective composition is coated onto a substrate and baked to obtain an antireflective film. The baking temperature can be, for example, 100℃-250℃, and the baking time can be, for example, 10s-120s. This baking process removes the solvent and causes the thermogenic acid-generating agent to produce acid, initiating a crosslinking reaction between the crosslinking agent and the resin. The final antireflective film comprises a solid molded product of the antireflective composition. Specifically, the baking temperature can be, for example, 100℃, 120℃, 150℃, 180℃, 200℃, 220℃, 230℃, 240℃, 250℃, etc., and the baking time can be, for example, 15s, 30s, 60s, 90s, 120s, etc. It should be noted that when the antireflective composition contains a second additive, such as ammonia, although the ammonia will partially evaporate during the baking process, it can still effectively reduce the linewidth roughness of the final patterned film and improve the white edge phenomenon.

[0072] During the patterning process, placing the aforementioned anti-reflective film on the lower layer of the photosensitive material film can effectively reduce the line width roughness of the pattern formed after exposure and development of the photosensitive material film. For example, reducing the line width roughness of a pattern with a resolution of 190nm to 3.7nm or below can also effectively improve or even eliminate the white edge phenomenon of the patterned film.

[0073] This application also provides a patterning process, including:

[0074] S11. Coat the aforementioned antireflective composition provided in the embodiments of this application onto the substrate to form an antireflective film on the substrate;

[0075] S12. A photosensitive material film is formed on the surface of the anti-reflective film;

[0076] S13. Expose and develop the photosensitive material film using a photomask to form a patterned film on the substrate;

[0077] S14. Etching to obtain a patterned substrate.

[0078] In some embodiments of this application, the substrate may be, for example, a silicon wafer. In other embodiments, the substrate includes a silicon wafer, on which other films, such as epitaxial layers, metal layers, dielectric layers, modification layers, or complementary layers, are also stacked.

[0079] In some embodiments of this application, in step S01, an antireflective composition can be coated onto the substrate surface using a spin-coating method. Specifically, depending on the size of the substrate, an appropriate volume of the antireflective composition is spin-coated onto the substrate.

[0080] In this embodiment of the application, step S01, after the spin coating, further includes baking the substrate coated with the antireflective composition. The baking temperature can be, for example, 100℃-250℃, and the baking time can be, for example, 10s-120s. The baking removes the solvent and causes the thermogenic acid-generating agent to produce acid, initiating a crosslinking reaction between the crosslinking agent and the resin. The resulting antireflective film comprises a solid molded product of the antireflective composition. Specifically, the baking temperature can be, for example, 100℃, 120℃, 150℃, 180℃, 200℃, 220℃, 230℃, 240℃, 250℃, etc., and the baking time can be, for example, 15s, 30s, 60s, 90s, 120s, etc.

[0081] In some embodiments of this application, step S02, forming a photosensitive material film on the surface of the antireflective film, includes: spin-coating a photosensitive material composition onto the surface of the antireflective film. The photosensitive material composition may include, for example, a polyacrylate resin, a photoacid-generating agent, and a solvent. In some specific embodiments, the photosensitive material composition further includes a photodegrading alkali and / or an acid quencher, the acid quencher being used to capture acid. In some embodiments of this application, after coating the photosensitive material composition, a baking process may be performed to remove the solvent from the photosensitive material coating, forming a photosensitive material film.

[0082] In some embodiments of this application, in step S03, exposing and developing the photosensitive material film using a photomask can be achieved by exposing the photosensitive material film to an exposure light source through a photomask, thereby changing the solubility of the photosensitive material, followed by development processing to transfer the pattern or its complementary pattern on the photomask onto the photosensitive material film. In some embodiments, the wavelength of the exposure light source can be, for example, 150nm-350nm.

[0083] The aforementioned development can be achieved by using a developer to develop the exposed photosensitive material film, thereby forming a patterned film on the substrate. The developer can be, for example, one that alters the chemical properties and solubility of the exposed portion of the photosensitive material film. The predetermined pattern can be obtained by cleaning the exposed film layer with the developer solution. The cleaning time ranges from 10s to 300s, and can be a single-step or multi-step cleaning process.

[0084] In step S03 above, the developing process can select a suitable developing solution according to the properties of the film layer of the photosensitive composition; for example, an alkaline developing solution or an organic solvent. In some embodiments of this application, the developing solution includes a 0.5-5% (w / w) aqueous solution of tetramethylammonium hydroxide (TMAH) and n-butyl acetate. The contact development time between the developing solution and the exposed film layer can be 10s-120s.

[0085] In some embodiments of this application, the patterned film obtained in step S03 has a linewidth roughness of ≤3.7nm for a pattern with a resolution of 190nm; specifically, the linewidth roughness of the patterned film with a resolution of 190nm can be, for example, 3.70nm, 3.68nm, 3.65nm, 3.60nm, 3.58nm, 3.55nm, 3.52nm, 3.50nm, 3.48nm, 3.45nm, 3.42nm, 3.40nm, 3.38nm, 3.35nm, 3.32nm, 3.30nm, 3.28nm, 3.27nm, 3.26nm, 3.25nm, 3.24nm, 3.22nm, 3.21nm, 3.2nm, etc.

[0086] In step S04, the patterned film selectively protects the underlying substrate material during etching. Under certain etching conditions, parts of the patterned film and the unprotected substrate material are etched, but the etching rate of the protected areas is slower than that of the unprotected areas. Ultimately, a pattern is formed on the substrate material, i.e., the pattern is transferred to the substrate to obtain a patterned substrate. The etching process can specifically involve HF etching, ion etching, or ion implantation to transfer the pattern to the substrate.

[0087] This application also provides a patterned substrate, which is fabricated using the patterning process provided in this application. The critical dimensions and linewidth roughness of the pattern on this patterned substrate can reach industry-leading levels, and it can be used to provide high-precision, high-reliability semiconductor devices, such as high-precision, high-reliability integrated circuits.

[0088] This application also provides a semiconductor device, which includes a patterned substrate and a functional layer disposed on the patterned substrate, as provided in this application.

[0089] Because it is fabricated using the patterned substrate provided in the embodiments of this application, the semiconductor device provided in the embodiments of this application can have both high precision and high reliability.

[0090] In this application embodiment, there are no special limitations on the structure of the semiconductor device. Those skilled in the art can design it based on actual application needs and prepare it using the acid-sensitive resin, photosensitive composition, patterned film, or patterned substrate provided in this application embodiment. In this application embodiment, the semiconductor device includes, but is not limited to, integrated circuit devices such as chips. It is understood that the semiconductor device provided in this application embodiment also includes a functional layer, which may include any structure applicable to the semiconductor device, such as metal wiring, active devices, passive devices, etc.

[0091] This application also provides a method for fabricating a semiconductor device, comprising:

[0092] S21. The anti-reflective composition provided in the embodiments of this application is coated on a substrate to form an anti-reflective film on the substrate;

[0093] S22. A photosensitive material film is formed on the surface of the anti-reflective film;

[0094] S23. Expose and develop the photosensitive material film using a photomask to form a patterned film on the substrate;

[0095] S24. Etching to obtain a patterned substrate;

[0096] S25. Prepare the functional layer to obtain the semiconductor device.

[0097] The above preparation method is suitable for large-scale industrial production and can produce high-precision, high-reliability semiconductor devices.

[0098] Steps S21, S22, S23, and S24 described above can be found in the previous description of the patterning process, and will not be repeated here. Step S25 can be performed using any process familiar to those skilled in the art, and this application does not impose any restrictions on it.

[0099] The technical solution of this application will be described in detail below with reference to several embodiments.

[0100] Example 1

[0101] An antireflective composition comprising the following components in the indicated mass amounts:

[0102] 2.8% resin (specifically, a polymethacrylate resin, wherein the hydroxyl-containing structural unit is derived from hydroxyethyl methacrylate, and the hydroxyl-containing structural unit accounts for 40% by mass in the resin), 0.0004% first additive (specifically, pyrrole), 0.1% thermal acid-producing agent (specifically, pyridinium p-benzenesulfonate), 0.5% crosslinking agent (specifically, tetramethoxymethyl urea), and the balance being solvent;

[0103] Specifically, the structural units derived from hydroxyethyl methacrylate are shown in Formula A. Formula A.

[0104] Example 2

[0105] An antireflective composition comprising the following components in the indicated mass amounts:

[0106] 2.8% resin (specifically, a polymethacrylate resin, wherein the hydroxyl-containing structural unit in the resin accounts for 40% by mass, and the hydroxyl-containing structural unit is derived from hydroxyethyl methacrylate), 0.0002% of the first additive (specifically, pyrrole), 0.0002% of the second additive (specifically, triethylamine), 0.1% of the heat-generating acid agent (specifically, pyridinium p-benzenesulfonate), 0.5% of the crosslinking agent (specifically, tetramethoxymethyl glycourea), and the balance solvent (specifically, PGME).

[0107] Example 3

[0108] 2.8% resin (specifically, a polymethacrylate resin, wherein the hydroxyl-containing structural units are derived from hydroxyethyl methacrylate, and the hydroxyl-containing structural units constitute 40% of the resin by mass), 0.0004% of a second additive (specifically, ammonia), 0.1% of a heat-generating acid agent (specifically, pyridinium p-benzenesulfonate), 0.5% of a crosslinking agent (specifically, tetramethoxymethyl urea), and the balance solvent (specifically, PGME).

[0109] Example 4

[0110] 2.8% resin (specifically, a polymethacrylate resin, wherein the hydroxyl-containing structural unit is derived from hydroxyethyl methacrylate, and the hydroxyl-containing structural unit accounts for 40% by mass in the resin), 0.0006% of a second additive (specifically, 6-hydroxypurine), 0.1% of a heat-generating acid agent (specifically, pyridinium p-benzenesulfonate), 0.5% of a crosslinking agent (specifically, tetramethoxymethyl glycourea), and the balance solvent (specifically, PGME).

[0111] Set the following comparison ratio.

[0112] Comparative Example 1

[0113] The difference from Example 1 is that the antireflective composition of Comparative Example 1 does not contain the first additive.

[0114] Exposure performance test 1

[0115] Using a 12-inch silicon wafer as a substrate, antireflective compositions of each embodiment and comparative example were coated on the substrate surface and baked at 205°C for 60 seconds to obtain a substrate with an antireflective film on the surface.

[0116] The photosensitive composition was uniformly coated onto the substrate using a spin coater and baked at 120°C for 60 seconds to form a photosensitive material film with a thickness of 150 nm. Dry exposure was performed using a krypton fluoride excimer laser with air as the medium. Afterwards, it was baked at 95°C for 60 seconds, developed using a 2.38% tetramethylammonium hydroxide aqueous solution at 23°C for 60 seconds, washed with water, and dried to form a patterned film. The linewidth of the patterned film was 190 nm (i.e., the resolution of the patterned film was 190 nm). The linewidth roughness of the patterned films prepared in each embodiment and comparative example was measured using a scanning electron microscope (SEM) and summarized in Table 1-1. Table 1 also summarizes the optimal exposure energy BE, optimal focal length BF, depth of focus DOF, and exposure energy margin EL for each embodiment and comparative example 1. SEM images of the patterned films of Examples 1 to 3 and Comparative Example 1 can be found sequentially. Figures 1 to 4 .

[0117] Exposure performance test 2

[0118] The photosensitive composition of Example 4 was uniformly coated onto the above-mentioned substrate using a spin coater and baked at 110°C for 60 seconds to form a photosensitive material film with a thickness of 90 nm. Wet exposure was performed using an argon fluoride excimer laser with water as the medium. The linewidth of the patterned film was 110 nm (i.e., the resolution of the patterned film was 110 nm), and other conditions were the same as in exposure performance test 1; the results are shown in Tables 1-2, and the SEM images of the obtained patterned film are shown in [reference needed]. Figure 5 .

[0119] Table 1-1

[0120] Case LWR / nm <![CDATA[BE(mJ / cm 2 )]]> BF / μm DOF / nm <![CDATA[EL(nm / (mJ·cm -2 ))]]> Example 1 3.53 29.53 0 220 24.36％ Example 2 3.21 29.58 0 220 24.33％ Example 3 3.76 30.67 0 220 26.21％ Example 4 3.63 30.02 0 220 25.01％ Comparative Example 1 4.08 30.91 0 220 27.20％

[0121] Table 1-2

[0122] Case LWR / nm <![CDATA[BE(mJ / cm 2 )]]> BF / μm DOF / nm <![CDATA[EL(nm / (mJ·cm -2 ))]]> Example 4 3.02 36.91 0 280 38.32％

[0123] As can be seen from the data in Tables 1-1 and 1-2, the anti-reflective composition provided in the embodiments of this application can effectively reduce the linewidth roughness of the patterned film without significantly affecting other exposure properties of the photosensitive material film, and is beneficial to improving the white edge phenomenon of the patterned film in the top view. Figures 1 to 4 It can be seen that the white edge phenomenon is most serious in the pattern obtained by Comparative Example 1.

[0124] It should be understood that the use of the terms "first," "second," and various numerical designations in this document is merely for descriptive convenience and is not intended to limit the scope of this application.

[0125] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after it are in an "or" relationship.

[0126] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0127] In this application, "-" indicates a range value, including the endpoint values ​​at both ends. For example, the value of a can be 0.5-15, meaning that the value of a can be between 0.5 and 15, and includes the endpoint values ​​of 0.5 and 15.

Claims

1. An antireflective composition, characterized in that, The resin comprises resin, additives, and solvents; the resin includes one or more of polyhydroxystyrene resins, polyester resins, and polyacrylate resins; the polyhydroxystyrene resin includes structural units derived from hydroxystyrene, and both the polyester resin and the polyacrylate resin have hydroxyl-containing structural units; the sum of the mass of the hydroxystyrene-derived structural units and the hydroxyl-containing structural units accounts for 10%-50% of the total mass of the resin; The additive includes a first additive; the first additive includes one or more of pyrazole, pyrrole, tetrahydropyrrole, pyrimidine, purine, adenine and 6-hydroxypurine; The mass of the additive is less than or equal to 0.05% of the total mass of the resin.

2. The antireflective composition according to claim 1, characterized in that, The additive accounts for 0.005%-0.05% of the total mass of the resin.

3. The antireflective composition according to claim 1, characterized in that, The resin accounts for 0.4%-5% of the mass of the antireflective composition.

4. The antireflective composition according to claim 1, characterized in that, The solvent comprises one or more of propylene glycol methyl ether acetate, 2-ethyl-1,3-propanediol, 1,4-butyrolactone, methyl 2-hydroxyisobutyrate, propylene glycol methyl ether, ethyl lactate, and cyclohexanone; the solvent accounts for 93.5%-99.5% of the mass of the antireflective composition.

5. The antireflective composition according to claim 1, characterized in that, It also includes a crosslinking agent; the crosslinking agent accounts for 0.05%-1% of the mass of the antireflective composition.

6. The antireflective composition according to claim 1, characterized in that, It also includes a compound that provides an acid; the compound that provides the acid accounts for 0.01%-0.5% of the mass of the antireflective composition.

7. The antireflective composition according to any one of claims 1-6, characterized in that, The additive also includes a second additive; the second additive includes one or more of ammonia, substituted or unsubstituted aniline, substituted or unsubstituted naphthylamine, and substituted or unsubstituted alkylamine.

8. The antireflective composition according to claim 7, characterized in that, The mass ratio of the first additive to the second additive is 1:9 to 9:

1.

9. An anti-reflective film, characterized in that, The antireflective film comprises a solid molded product of the antireflective composition as described in any one of claims 1-8.

10. A patterning process, characterized in that, include: The antireflective composition as described in any one of claims 1-8 is coated on a substrate to form an antireflective film on the substrate; A photosensitive material film is formed on the surface of the antireflective film; The photosensitive material film is exposed and developed using a photomask to form a patterned film on the substrate; Etching yields a patterned substrate.

11. A patterned substrate, characterized in that, The patterned substrate is prepared using the patterning process described in claim 10.

12. A semiconductor device, characterized in that, The semiconductor device includes a patterned substrate as described in claim 11 and a functional layer disposed on the patterned substrate.

13. A method for fabricating a semiconductor device, characterized in that, include: The antireflective composition according to any one of claims 1-8 is coated on a substrate to form an antireflective film on the substrate; A photosensitive material film is formed on the surface of the antireflective film; The photosensitive material film is exposed and developed using a photomask to form a patterned film on the substrate; Etching yields a patterned substrate; A functional layer is fabricated to obtain a semiconductor device.

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