Double-layer resin film as well as preparation method and application thereof

Abstract

The invention discloses a double-layer resin film as well as a preparation method and application thereof. The double-layer resin film comprises a resist layer and a top coating film layer coated on the resist layer. The double-layer resin film disclosed by the invention is applied to ArF immersion photoetching, so that the problems that the performance of the photoresist is reduced and the defects are increased can be reduced.

Description

Technical Field

[0001] The present invention relates to a double-layer resin film, a preparation method thereof and an application thereof. Background Art

[0002] In recent years, due to the continuous high integration of large scale integrated circuits (LSIs), for the miniaturization of lithography processes, especially for ultra-fine pattern processes below the 30 nm node, the resolution of photoresists used in lithography processes has become a decisive important factor. Therefore, in the commonly used g-line or i-line regions, the wavelength of the exposure light has also been further shortened, and thus research on lithography using deep ultraviolet light, KrF excimer lasers, and ArF excimer lasers has attracted much attention.

[0003] After processes such as spin coating, baking, exposure, development, and etching of the photoresist, fine patterns on the mask can be transferred to the substrate. The shorter the exposure wavelength, the higher the resolution of the photoresist. In recent years, as the semiconductor manufacturing process has gradually improved, ArF immersion lithography has become the dominant lithography process for advanced processes. ArF immersion lithography continues the ArF light source, adds a water medium between the photoresist and the lithography machine lens, increases the numerical aperture (NA) of the lithography machine, shortens the wavelength irradiated on the photoresist, and improves the resolution and depth of focus of the photoresist.

[0004] However, component exchange occurs between the photoresist and water, resulting in contamination and damage to the water and the lithography machine lens, a decrease in the performance of the photoresist, and an increase in defects. Increasing the hydrophobicity of the photoresist film-forming resin and the activation energy of the protecting group can inhibit the leaching of small molecules, but the effect is limited. Therefore, it is necessary to consider forming a water-resistant coating on the surface of the photoresist. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a double-layer resin film, a preparation method thereof and an application thereof in order to overcome the problems of decreased photoresist performance and increased defects in ArF immersion lithography. The double-layer resin film of the present invention has strong stability and excellent pattern resolution. In addition, the top coating film containing the polymer of the present invention has any one of the following advantages: better alkali solubility, good hydrophobicity, a higher sliding angle, a higher receding contact angle, and a faster dissolution rate.

[0006] The present invention provides a double-layer resin film, which includes a resist layer and a top coating film layer coated on the resist layer;

[0007] The components of the top coating film include a polymer;

[0008] The polymer is prepared by the following method; the preparation method of the polymer comprises the following steps: in the presence of an initiator, polymerize the monomer shown in formula A and the monomer shown in formula B in an organic solvent to obtain the polymer;

[0009] By weight, the weight of monomer A is 1-15 parts; the weight of monomer B is 1-10 parts;

[0010]

[0011] n is an integer from 1 to 10.

[0012] In a certain embodiment of the present invention, the resist layer is a layer formed from tai-6990PH (e.g., manufactured by TOK) photoresist.

[0013] In a certain embodiment of the present invention, the thickness of the double-layer resin film is 175-225 nm, such as 200 nm.

[0014] In a certain embodiment of the present invention, the thickness of the top coating film layer is 35-60 nm, such as 50 nm.

[0015] In a certain embodiment of the present invention, the thickness of the resist layer is 140-165 nm, such as 150 nm.

[0016] In a certain embodiment of the present invention, in the polymer, by weight, the weight of the monomer shown in formula A is 2-10 parts, preferably 2 parts, 4 parts, 5 parts, 8 parts or 10 parts.

[0017] In a certain embodiment of the present invention, in the polymer, by weight, the weight of the monomer shown in formula B is 1-6 parts, preferably 1 part, 1.5 parts, 2 parts, 3.5 parts or 6 parts.

[0018] In a certain embodiment of the present invention, in the polymer, the initiator is preferably an azo initiator, such as azobisisobutyronitrile.

[0019] In a certain embodiment of the present invention, in the polymer, by weight, the weight of the initiator is 0.05-0.3 parts, preferably 0.1 part.

[0020] In a certain embodiment of the present invention, in the polymer, the organic solvent is a ketone solvent, preferably selected from one or more of methyl ethyl ketone, N-methylpyrrolidone and cyclohexanone, preferably methyl ethyl ketone.

[0021] In a certain embodiment of the present invention, in the polymer, by weight, the weight of the organic solvent is 10-20 parts, preferably 15 parts.

[0022] In a certain embodiment of the present invention, the weight-average molecular weight (Mw) of the polymer is 5000 - 13000, such as 5700 - 12200.

[0023] In a certain embodiment of the present invention, in the polymer, in the monomer represented by formula B, n is 3.

[0024] In a certain embodiment of the present invention, in the method for preparing the polymer, the temperature of the polymerization reaction is 60 - 100 °C, such as 70 °C.

[0025] In a certain embodiment of the present invention, in the method for preparing the polymer, the time of the polymerization reaction is 10 - 24 hours, such as 12 hours.

[0026] In a certain embodiment of the present invention, the raw materials for the polymerization reaction are the monomer represented by formula A, the monomer represented by formula B, the initiator, and the organic solvent.

[0027] In a certain embodiment of the present invention, in the method for preparing the polymer, after the polymerization reaction, a post-treatment step is further included, such as cooling, precipitation, and drying.

[0028] Among them, the solvent used in the precipitation is preferably an alkane solvent, such as n-hexane.

[0029] Among them, the amount of the solvent used in the precipitation is conventional for this type of reaction in the art. The weight ratio of n-hexane to the organic solvent can be (3 - 4):1, preferably 3.3:1.

[0030] Among them, the drying can be vacuum drying, such as vacuum drying at 50 °C for 24 hours.

[0031] In a certain embodiment of the present invention, in the method for preparing the polymer, the polymerization reaction can be carried out under an inert gas (such as nitrogen).

[0032] In a certain embodiment of the present invention, the polymer is any one of the following polymers:

[0033] Polymer P1: By weight, the weight of the monomer represented by formula A is 2 parts, the weight of the monomer represented by formula B is 1 part, the weight of methyl ethyl ketone is 15 parts, and the weight of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight can be 5784;

[0034] Polymer P2: By weight, the weight of the monomer represented by formula A is 4 parts, the weight of the monomer represented by formula B is 1.5 parts, the weight of methyl ethyl ketone is 15 parts, and the weight of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight can be 7851;

[0035] Polymer P3: By weight, the weight fraction of the monomer represented by Formula A is 5 parts, the weight fraction of the monomer represented by Formula B is 2 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight average molecular weight can be 8938;

[0036] Polymer P4: By weight, the weight fraction of the monomer represented by Formula A is 8 parts, the weight fraction of the monomer represented by Formula B is 3.5 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight average molecular weight can be 10089;

[0037] Polymer P5: By weight, the weight fraction of the monomer represented by Formula A is 10 parts, the weight fraction of the monomer represented by Formula B is 6 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight average molecular weight can be 12157;

[0038] Among Polymers P1 to P5, monomer B is

[0039] In a certain embodiment of the present invention, the double-layer resin film is prepared by the following method; the preparation method of the top coating film includes the following steps: coating the top coating liquid on the surface of a silicon wafer and drying it;

[0040] The top coating liquid includes components with the following mass fractions: 1-5% of the aforementioned polymer and 95-99% of an organic solvent.

[0041] In a certain embodiment of the present invention, in the top coating liquid, the organic solvent is an alcohol solvent, preferably 4-methyl-2-pentanol.

[0042] In a certain embodiment of the present invention, in the top coating liquid, the mass fraction of the polymer is 2-3%, for example, 3%.

[0043] In a certain embodiment of the present invention, in the top coating liquid, the mass fraction of the organic solvent is 96-99%, for example, 97%.

[0044] In a certain embodiment of the present invention, the top coating liquid is composed of the aforementioned polymer and the aforementioned organic solvent, and the types and mass fractions of the polymer and the organic solvent are the same as those described above.

[0045] In a certain embodiment of the present invention, in the top coating film, before coating the top coating liquid, it is preferably filtered using a membrane filter; more preferably, the pore size of the membrane filter is 0.2 μm.

[0046] In a certain embodiment of the present invention, in the top coating film, the drying temperature can be 50 - 120 °C, preferably 80 °C.

[0047] In a certain embodiment of the present invention, in the top coating film, the drying time is 70 - 180 seconds, preferably 90 seconds.

[0048] In a certain embodiment of the present invention, in the top coating film, the coating method can be a conventional coating method in the art, such as spin coating.

[0049] In a certain embodiment of the present invention, in the top coating film, the spin coating can be conventional in the art, and preferably a spinner with a rotation speed of 1400 - 1600 rpm (such as 1500 rpm) is used.

[0050] In a certain embodiment of the present invention, the double - layer resin film is composed of an anti - resist layer as described above and a top coating film layer coated on the anti - resist layer as described above.

[0051] The present invention also provides a method for preparing the above double - layer resin film, which includes the following steps: coating an anti - resist solution on the surface of a substrate (silicon wafer) to obtain an anti - resist layer; coating a top coating liquid on the anti - resist layer to obtain the double - layer resin film.

[0052] The anti - resist layer is a conventional anti - resist layer in the art, and its preparation method preferably includes the following steps: coating an anti - resist solution on the surface of a silicon wafer and drying it.

[0053] In a certain embodiment of the present invention, in the method for preparing the double - layer resin film, in the preparation method of the anti - resist layer, the coating is conventional in this type of reaction in the art, and preferably spin coating.

[0054] In a certain embodiment of the present invention, in the method for preparing the double - layer resin film, the top coating liquid is preferably filtered using a membrane filter. More preferably, the pore size of the membrane filter is 0.2 μm.

[0055] In a certain embodiment of the present invention, in the method for preparing the double - layer resin film, the drying temperature is preferably 70 - 120 °C, such as 80 °C or 100 °C.

[0056] In a certain embodiment of the present invention, in the method for preparing the double - layer resin film, the drying time is preferably 80 - 120 seconds, such as 90 seconds.

[0057] The present invention also provides a top coating film, which includes the above polymer.

[0058] In a certain embodiment of the present invention, the top coating film is prepared by the following method; the preparation method of the top coating film includes the following steps: coating the above top coating liquid on the surface of a silicon wafer and drying it.

[0059] The conditions and operations of the obtained top coating film are the same as those described above.

[0060] The present invention also provides a method for preparing the above-mentioned top coating film, which includes the following steps: coating the above-mentioned top coating liquid on the surface of a silicon wafer.

[0061] The conditions and operations of the method for preparing the top coating film are the same as those described above.

[0062] The present invention also provides a polymer, which is prepared by the following method; the method for preparing the polymer includes the following steps: in the presence of an initiator, polymerizing the monomer shown in formula A and the monomer shown in formula B in an organic solvent to obtain the polymer;

[0063] By weight, the weight of monomer A is 1-15 parts; the weight of monomer B is 1-10 parts;

[0064]

[0065] n is an integer from 1 to 10.

[0066] The type and weight of the polymer are the same as those described above.

[0067] The present invention also provides a method for preparing the above-mentioned polymer, which includes the following steps: in the presence of an initiator, polymerizing the monomer shown in formula A and the monomer shown in formula B in an organic solvent to obtain the polymer;

[0068] By weight, the weight of monomer A is 1-15 parts; the weight of monomer B is 1-10 parts;

[0069]

[0070] n is an integer from 1 to 10.

[0071] The conditions and operations of the method for preparing the polymer are the same as those described above.

[0072] The present invention also provides an application of the above-mentioned polymer, the above-mentioned top coating film or the above-mentioned double-layer resin film in ArF immersion lithography.

[0073] On the basis of conforming to the common knowledge in the art, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred examples of the present invention.

[0074] The reagents and raw materials used in the present invention are all commercially available. Among them, monomers A and B are both purchased from Suzhou Meiming Electronic Technology Co., Ltd.

[0075] The positive and progressive effects of the present invention are as follows: The double-layer resin film of the present invention has the advantages of strong stability and excellent pattern resolution. The top coating film containing the polymer of the present invention is insoluble in water but soluble in photoresist developers (especially alkaline developers), and does not interact with the photoresist. It has at least the following advantages: better alkali solubility and hydrophobicity, a higher sliding angle, a higher receding contact angle, and a faster dissolution rate. Detailed implementation mode

[0076] The present invention will be further described below by way of examples, but the present invention is not limited to the scope of the described examples. For the experimental methods without specific conditions indicated in the following examples, they are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0077] Preparation method:

[0078] Replace the air in the glass flask with nitrogen to make the atmosphere in the flask nitrogen. Then, add the components in Table 1 to the glass flask equipped with a condenser in sequence. Heat the reaction solution to 70 °C and stir for 12 hours. After the reaction is terminated, pour it into 50 g of n-hexane and stir, and take out the generated precipitate. Dry it at 50 °C for 24 hours to form a white solid, obtaining the polymer, and the molecular weight is calculated by gel permeation chromatography (GPC, standard substance: polystyrene).

[0079]

[0080] Table 1 Components in the polymer

[0081] Polymer Monomer A Monomer B Methyl ethyl ketone Azobisisobutyronitrile <![CDATA[M W > P1 2g 1g 15g 0.1g 5784 P2 4g 1.5g 15g 0.1g 7851 P3 5g 2g 15g 0.1g 8938 P4 8g 3.5g 15g 0.1g 10089 P5 10g 6g 15g 0.1g 12157

[0082] Preparation of the top coating solution

[0083] Dissolve 100 g of the synthesized polymer in 900 g of the solvent 4-methyl-2-pentanol (MIBC), and then adjust the concentration of the polymer to 3 wt% with 2300 g of 4-methyl-2-pentanol to obtain a uniform and transparent top coating solution.

[0084] Fabrication of the top coating film

[0085] Filter each top coating solution with a membrane filter (0.2 μm), and then spin-coat it onto a silicon wafer with a spinner at a rotation speed of 1500 rpm, and dry it on a hot plate at 80 °C for 90 seconds to obtain a uniform top coating film of about 50 nm on the silicon wafer.

[0086] Advancing contact angle / receding contact angle evaluation test

[0087] The advancing contact angle and the receding contact angle of water droplets were measured by the expansion / contraction method at 20 °C using a CA-X type apparatus manufactured by Kyowa Surface Science Co., Ltd. for the top coating film and the single-layer resist film formed on a silicon wafer.

[0088] Alkaline developer solubility test

[0089] For the top coating film and the single-layer resist film formed on a silicon wafer, the dissolution rate in a 2.38% aqueous solution of tetramethylammonium hydroxide (alkaline developer) was measured at 20 °C using a resist developer analyzer RDA-790 (manufactured by Litho Tech Japan Corporation).

[0090] Fabrication of resist / top coating double-layer resin film

[0091] After spin-coating a resist solution (the photoresist is tai-6990PH manufactured by TOK, and the photoacid generator (PAG) is triphenylsulfonium trifluoromethanesulfonate manufactured by Midori Kagaku Co., Ltd.) onto a silicon wafer using a spinner, it was dried on a hot plate at 100 °C for 90 seconds to form a resist film with a film thickness of about 150 nm. After spin-coating the filtered top coating solution (using a membrane filter (0.2 μm)) onto this resist film using a spinner, it was dried on a hot plate at 80 °C for 90 seconds to form a double-layer resin film with an overall film thickness of about 200 nm (a double-layer film composed of a resist layer and a top coating layer).

[0092] For the double-layer resin film formed on a silicon wafer, the following pure water immersion treatment and exposure imaging test were carried out.

[0093] Pure water immersion test

[0094] Five silicon wafers with the double-layer resin film (a double-layer film composed of a resist layer and a top coating layer) formed thereon and a silicon wafer with a single-layer resist film obtained above were each immersed in 20 ml of pure water at 20 °C for 10 minutes. After extracting the eluate, the extract was measured by ion chromatography to confirm the presence or absence of triphenylsulfonium trifluoromethanesulfonate in the eluate.

[0095] Exposure imaging (pattern formation) test

[0096] The silicon wafers with the double-layer resin film (a double-layer film composed of a resist layer and a top coating layer) formed by pre-baking at 80 °C for 90 seconds and the silicon wafers with a single-layer resist film were exposed at 193 nm through a photomask. While rotating the exposed wafers, 2 minutes of pure water was dropped. Then, post-exposure baking was carried out at 120 °C for 60 seconds, and development was carried out using an alkaline developer. A 2.38% aqueous solution of tetramethylammonium hydroxide was used as the alkaline developer. The cross-section of the obtained pattern was observed using a scanning electron microscope, and the pattern resolution was characterized by the degree of deformation of the rectangle.

[0097] Evaluation Test of Top Coating Film in Table 2

[0098]

[0099]

[0100] Evaluation Test of Double - Layer Resin Film in Table 3

[0101] Double-layer resin film Pure water immersion experiment Pattern resolution Double-layer resin film 1 No eluted triphenylsulfonium trifluoromethanesulfonate detected Rectangle Double-layer resin film 2 No eluted triphenylsulfonium trifluoromethanesulfonate detected Rectangle Double-layer resin film 3 No eluted triphenylsulfonium trifluoromethanesulfonate detected Rectangle Double-layer resin film 4 No eluted triphenylsulfonium trifluoromethanesulfonate detected Rectangle Double-layer resin film 5 No eluted triphenylsulfonium trifluoromethanesulfonate detected Rectangle Single-layer resist film Eluted triphenylsulfonium trifluoromethanesulfonate detected Swelling and deformation

[0102] Conclusion: The top coating film prepared from polymers P1 - P5 has a higher sliding angle, a higher receding contact angle and a faster dissolution rate. It can be seen that the top coating film prepared from the polymers P1 - P5 of the present invention has better alkali solubility and hydrophobicity. In addition, the prepared double - layer resin film has strong stability and excellent pattern resolution. When the double - layer resin film of the present invention is immersed in pure water, no peaks attributable to triphenylsulfonium trifluoromethanesulfonate or its decomposition products are detected. It can be seen that by setting the top coating, the dissolution of the photo - acid generator, which is an anti - resist component, in water is inhibited.

Claims

1. A double-layer resin film, characterized in that, It includes a resist layer and a top coating film layer coated on the resist layer; The components of the top coating film include a polymer; The polymer is prepared by the following method; the preparation method of the polymer includes the following steps: in the presence of an initiator, polymerize the monomer shown in formula A and the monomer shown in formula B in an organic solvent to obtain the polymer; By weight, the weight of monomer A is 1-15 parts; the weight of monomer B is 1-10 parts; n is an integer from 1 to 10.

2. The double-layer resin film according to claim 1, wherein It satisfies one or more of the following conditions; (1) The resist layer is a layer formed using tai-6990PH photoresist; (2) The thickness of the double-layer resin film is 175-225 nm, such as 200 nm; (3) The thickness of the coating film layer is 35-60 nm, such as 50 nm; (4) The thickness of the resist layer is 140-165 nm, such as 150 nm.

3. The double-layer resin film according to claim 1, wherein, It satisfies one or more of the following conditions; (1) In the polymer, by weight, the weight of the monomer shown in formula A is 2-10 parts, preferably 2 parts, 4 parts, 5 parts, 8 parts or 10 parts; (2) In the polymer, by weight, the weight of the monomer shown in formula B is 1-6 parts, preferably 1 part, 1.5 parts, 2 parts, 3.5 parts or 6 parts; (3) In the polymer, the initiator is an azo initiator, such as azobisisobutyronitrile; (4) In the polymer, by weight, the weight of the initiator is 0.05-0.3 parts, preferably 0.1 part; (5) In the polymer, the organic solvent is a ketone solvent, preferably selected from one or more of methyl ethyl ketone, N-methylpyrrolidone and cyclohexanone, preferably methyl ethyl ketone; (6) In the polymer, by weight, the weight of the organic solvent is 10-20 parts, preferably 15 parts; (7) In the polymer, the weight average molecular weight of the polymer is 5000-13000, such as 5700-12200; (8) In the polymer, in the monomer shown in formula B, n is 3.

4. The double-layer resin film according to claim 1, wherein, It satisfies one or more of the following conditions; (1) In the preparation method of the polymer, the temperature of the polymerization reaction is 60-100 °C, such as 70 °C; (2) In the preparation method of the polymer, the time of the polymerization reaction is 10-24 hours, such as 12 hours; (3) In the preparation method of the polymer, the raw materials of the polymerization reaction are the monomer shown in formula A, the monomer shown in formula B, the initiator and the organic solvent; (4) In the preparation method of the polymer, after the polymerization reaction, there is also a post-treatment step, such as cooling, precipitation and drying; preferably, the solvent used in the precipitation is an alkane solvent, such as n-hexane; further preferably, the weight ratio of n-hexane to the organic solvent is (3-4):1, preferably 3.3:1; preferably, the drying is vacuum drying, such as vacuum drying at 50 °C for 24 hours; (5) In the method for preparing the polymer, the polymerization reaction is carried out under an inert gas, for example, under nitrogen.

5. The double-layer resin film according to claim 1, wherein, The polymer is any one of the following polymers; Polymer P1: By weight, the weight fraction of the monomer represented by formula A is 2 parts, the weight fraction of the monomer represented by formula B is 1 part, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight is 5784; Polymer P2: By weight, the weight fraction of the monomer represented by formula A is 4 parts, the weight fraction of the monomer represented by formula B is 1.5 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight is 7851; Polymer P3: By weight, the weight fraction of the monomer represented by formula A is 5 parts, the weight fraction of the monomer represented by formula B is 2 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight is 8938; Polymer P4: By weight, the weight fraction of the monomer represented by formula A is 8 parts, the weight fraction of the monomer represented by formula B is 3.5 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight is 10089; Polymer P5: By weight, the weight fraction of the monomer represented by formula A is 10 parts, the weight fraction of the monomer represented by formula B is 6 parts, the weight fraction of methyl ethyl ketone is 15 parts, and the weight fraction of azobisisobutyronitrile is 0.1 part; the weight-average molecular weight is 12157; Among polymers P1 to P5, monomer B is 6. The double-layer resin film according to any one of claims 1-5, characterized in that, The double-layer resin film is prepared by the following method; the method for preparing the top coating film includes the following steps: coating the top coating liquid on the surface of the silicon wafer and drying it; The top coating liquid includes the following components by mass fraction: 1-5% of the polymer according to any one of claims 1-5 and 95-99% of an organic solvent; The organic solvent is preferably an alcohol solvent, more preferably 4-methyl-2-pentanol; The mass fraction of the polymer is preferably 2-3%, for example, 3%; The mass fraction of the organic solvent is preferably 96-99%, for example, 97%.

7. The double-layer resin film according to claim 6, wherein It satisfies one or more of the following conditions; (1) In the top coating film, before coating the top coating liquid, it is filtered using a membrane filter; preferably, the pore size of the membrane filter is 0.2 μm; (2) In the top coating film, the drying temperature is 50-120 °C, preferably 80 °C; (3) In the top coating film, the drying time is 70-180 seconds, preferably 90 seconds; (4) In the top coating film, the coating method is spin coating; (5) In the top coating film, the spin coating is carried out using a spinner with a rotation speed of 1400-1600 rpm, for example, a spinner with a rotation speed of 1500 rpm.

8. The double-layer resin film according to claim 1, wherein, The double-layer resin film is composed of the resist layer and a top coating film layer coated on the resist layer.

9. A method for preparing a double-layer resin film according to any one of claims 1-8, characterized in that, It includes the following steps: coating a resist solution on the surface of a substrate to obtain a resist layer; coating the top coating liquid on the resist layer to obtain a double-layer resin film; Preferably, it satisfies one or more of the following conditions; (1) The method for preparing the resist layer includes the following steps: coating a resist solution on the surface of a silicon wafer and drying it; preferably, the coating is spin coating; (2) The top coating liquid is filtered using a membrane filter; preferably, the pore size of the membrane filter is 0.2 μm; (3) The drying temperature is 70 - 120 °C, such as 80 °C or 100 °C; (4) The drying time is 80 - 120 seconds, such as 90 seconds.

10. Application of the double-layer resin film according to any one of claims 1 - 8 in ArF immersion lithography.

Images