Lithographic compositions for sustainable and more environmentally friendly solutions for edge protection layers and methods of using same

Abstract

The disclosed subject matter relates to a water soluble wafer edge protection layer (EPL) material for a sustainable / more environmentally friendly solution for semiconductor processing.

Description

[0001] background

[0002] field

[0003] The disclosed subject matter relates to water-soluble wafer edge protection layer (EPL) materials for sustainable / more environmentally friendly solutions in semiconductor processing.

[0004] Related technologies

[0005] Multiple anti-reflective layers and hard masks are used in advanced photolithography patterning processes. For example, when photoresists do not provide sufficient resistance to dry etching, a photoresist underlayer and / or anti-reflective coating that acts as a hard mask and provides high etch resistance during substrate etching is preferred. One approach is to incorporate silicon, titanium, zirconium, aluminum, or other metallic materials into a layer beneath an organic photoresist layer. Alternatively, another high-carbon-content anti-reflective or masking layer can be placed beneath a metal-containing anti-reflective layer to form a three-layer structure of high-carbon film / hard mask film / photoresist. Such layers can be used to improve the lithographic performance of imaging processes. However, metal contamination in lithography and etching tools, as well as cross-contamination between wafers during manufacturing, can be problems that should be avoided. These issues are becoming increasingly important for the introduction of spin-coated metal hard masks and metal-based EUV resists into next-generation device manufacturing technologies, with wafer edge cleaning being particularly critical.

[0006] A process and apparatus for reducing metal contamination during the manufacture of integrated circuit components is described in U.S. Patent No. 8,791,030 (“Iwao”), which is incorporated herein by reference in its entirety. According to Iwao, a masking agent is supplied to the edge of a wafer / substrate and baked to form a masking film (also known as an edge protection layer (“EPL”) or edge masking layer) at the edge of the wafer / substrate. A hard mask composition is then applied to the wafer / substrate and the EPL. A portion of the hard mask composition covering the edge protection layer is removed using an edge bead removal agent (“EBR”) and the hard mask composition is baked to form a hard mask. The EPL is then removed using an EPL removal solution. The result is a hard mask spaced apart from the edge of the wafer / substrate, thereby reducing contamination.

[0007] The masking agent for forming EPL is described in patent application PCT / EP2018 / 056322 (published as WO / 2018 / 167112) entitled "Photolithography Composition and Method of Use Therein," which is incorporated herein by reference in its entirety. The composition disclosed therein prevents metal contamination at substrate / wafer edges during the manufacture of electronic devices. As explained in PCT / EP2018 / 056322, it is desirable that the coated EPL can be easily removed at rates that achieve and / or maintain commercially acceptable process times without negative or damaging effects on the hard mask (such as those that can occur through wet etching).

[0008] PCT / EP2018 / 056322 further elaborates on the provisions of this article. Figures 2a-f The method for manufacturing an electronic device described herein is a common process for coating a masking agent to form an EPL. In this process, a metal hard mask composition or a metal oxide photoresist composition (collectively, “hard mask” or “hard mask composition”) is coated onto a substrate and the EPL (see Figure 2c). The EPL and the hard mask composition are then rinsed with an EBR and / or a backwashing agent (“BR”) material to remove at least a portion of the hard mask composition in contact with the EPL (see Figure 2d). Nevertheless, even after rinsing with EBR or BR, one or more portions of the hard mask composition in contact with the EPL may remain. For example, the hard mask composition may partially penetrate the EPL or undercut the edge of the EPL. Therefore, a certain amount of the hard mask and / or the components of the hard mask in contact with the EPL may not be removed during EBR rinsing. To date, no composition or process / method has been identified that provides simultaneous removal of both the remaining residual components (e.g., metals) for the EPL and the hard mask. Instead, the EPL removal step must be followed by a subsequent processing step (e.g., rinsing with an additional EBR) in which any remaining residual components of the hard mask are removed from the edges and near the surface of the wafer / substrate. This additional step is costly and time-consuming, and therefore inconsistent with achieving and / or maintaining commercially acceptable process times when utilizing EPL.

[0009] Notably, in the above process (and other known processes), a non-aqueous organic solvent is used to apply the EPL to avoid metal contamination of the wafer when using spin-coated metal hard masks or metal oxide resists (MOR). In such a process, the EPL is insoluble in the non-aqueous organic casting solvent used to deposit the hard mask or metal oxide resist (MOR). Next, the wafer edges are cleaned with the casting solvent to remove any metal-containing material on the wafer edges. Then, the EPL material on the wafer edges is removed using a non-aqueous solvent (which may be the same as or substantially the same as the solvent used to deposit the EPL). Finally, the wafer is baked to cure the metal-containing material. In this way, the wafer coated with the metal-containing material can safely undergo photolithography and etching processes without causing cross-contamination.

[0010] As can be seen from the above, the application and removal of organic solvents by EBRs require the use of significant amounts of organic solvents. This is not only expensive (due to the high cost of the organic solvents used), but also harmful to the environment. Therefore, it is necessary and desirable to limit (or even eliminate) the use of organic solvents when using EBRs.

[0011] The disclosed and claimed subject matter addresses this need by providing EPL materials that can be applied and removed using aqueous solvents rather than organic solvent-based removers. Because this process uses aqueous solvents, liquid waste disposal is cost-effective and environmentally friendly, thus providing a sustainable and environmentally friendly solution for semiconductor processing. The disclosed and claimed EPL system comprises a water-soluble polymer and an aqueous solvent as its main components. It can be spin-coated onto a substrate and, after baking, is insoluble in casting solvents containing metal materials. Furthermore, the EPL can be removed using aqueous removal solvents. Therefore, the disclosed and claimed subject matter relates to these sustainable and environmentally friendly EPL systems and their methods of use.

[0012] Overview

[0013] In one aspect, the disclosed subject matter includes EPL formulations that can be applied and removed using water-based (i.e., aqueous) solvents, wherein the EPL formulation comprises a water-soluble polymer and water as main components, and is substantially composed of or consists of the same components.

[0014] In another respect, the disclosed and claimed subject matter includes the use of the EPL formulations described herein. Brief description of the attached diagram

[0016] The accompanying drawings are included to provide a further understanding of the disclosed subject matter and are incorporated in and form part of this specification. They illustrate embodiments of the disclosed subject matter and, together with this specification, serve to explain the principles of the disclosed subject matter. In the drawings:

[0017] Figure 1 This describes a cross-section of the edge of a wafer / substrate on which EPL is applied;

[0018] Figures 2a-f This illustration depicts one embodiment of the method and process using the rinsing solution disclosed herein. In Figure 2a, a masking agent is applied to the edge of a substrate. In Figure 2b, the masking agent is heated to form an EPL. In Figure 2c, a hard mask composition is applied to the substrate and the EPL. In Figure 2d, the hard mask composition and the EPL are rinsed by an EBR to remove at least a portion of the hard mask composition in contact with the EPL. In Figure 2e, the hard mask composition is heated to form a hard mask. In Figure 2f, the EPL and residual hard mask components (e.g., metals such as tin or titanium) are removed from the edge of the wafer / substrate using a rinsing agent; and

[0019] Figure 3 Explanation of residual Zr on Si wafers measured using TXRF in Examples 1A, 1, 2, 3 and Comparative Example 1 (unit: 10). 10 atoms / cm 2 ).

[0020] definition

[0021] Unless otherwise stated, the following terms used in this specification and claims shall have the following meanings for the purposes of this application.

[0022] In this application, unless otherwise specified, the use of the singular includes the plural, and the terms “a / an” and “the” mean “at least one.” Furthermore, the use of the term “including” and other forms such as “includes” and “included” is not restrictive. Similarly, unless otherwise specified, terms such as “element” or “component” cover both elements or components that include one unit and elements or components that include more than one unit. As used herein, unless otherwise indicated, the conjunction “and” is intended to be inclusive and the conjunction “or” is not intended to be exclusive. For example, the phrase “or alternatively” is intended to be exclusive. As used herein, the term “and / or” refers to any combination of the foregoing elements, including the use of a single element.

[0023] "Substantially insoluble" is defined herein as less than 2% solubility, preferably less than 1% solubility, more preferably less than 0.5% solubility, and most preferably less than 0.1% solubility. "Substantially insoluble" also includes 0.0% solubility.

[0024] "Substantially free of" is defined herein as less than 2 wt%, preferably less than 1 wt%, more preferably less than 0.5 wt%, and most preferably less than 0.1 wt%. "Substantially free of" also includes 0.0 wt%. The term "free of" means 0.0 wt% as typically measured in the field.

[0025] As used herein, “about” or “approximately” is intended to correspond to ±5% of the stated value.

[0026] As used herein, "aqueous solvent" is a solvent comprising at least about 70 wt% water, more preferably at least about 75 wt% water, even more preferably at least about 80 wt% water, even more preferably at least about 85 wt% water, even more preferably at least about 95 wt% water, and most preferably at least about 99 wt% water. "Aqueous solvent" also includes water in the absence of other solvents, i.e., water that is substantially free of and / or free of other solvents.

[0027] As used herein, “non-aqueous solvent” means a solvent containing no more than about 10 wt% water, more preferably no more than about 5 wt% water, and most preferably no more than about 1 wt% water. “Non-aqueous solvent” also includes solvents that contain virtually no or no water in the absence of other solvents, i.e., solvents that are substantially free of and / or free of water.

[0028] As used herein, "aqueous removal solvent" is a solvent comprising at least about 70 wt% water, more preferably at least about 75 wt%, even more preferably at least about 80 wt%, even more preferably at least about 85 wt%, even more preferably at least about 95 wt% water, and most preferably at least about 99 wt% water. "Aqueous removal solvent" also comprises water in the absence of other solvents, i.e., water that is substantially free of and / or free of other solvents.

[0029] In a composition “consisting substantially of the said components”, such components may add up to 100% by weight of the composition or add up to less than 100% by weight (“wt%”). Where the components add up to less than 100% by weight, such a composition may contain small amounts of non-essential contaminants or impurities. For example, in one such embodiment, the cleaning composition may contain 2% by weight or less of impurities. In another embodiment, the cleaning composition may contain 1% by weight or less of impurities. In yet another embodiment, the cleaning composition may contain 0.05% by weight or less of impurities. In other such embodiments, the components may form at least 90 wt%, more preferably at least 95 wt%, more preferably at least 99 wt%, more preferably at least 99.5 wt%, most preferably at least 99.9 wt%, and may contain other components that do not substantially affect the performance of the cleaning composition. Otherwise, if there are no significant non-essential impurity components, it should be understood that the combination of all essential components substantially adds up to 100% by weight.

[0030] As used in this article, "C" x-y "" indicates the number of carbon atoms in the chain. For example, C 1-6 Alkyl refers to an alkyl chain having 1 to 6 carbon atoms (e.g., methyl, ethyl, propyl, butyl, pentyl, and hexyl). Unless otherwise specified, the chain may be straight or branched.

[0031] Unless otherwise indicated, "alkyl" means a hydrocarbon group that can be straight-chain, branched (e.g., methyl, ethyl, propyl, isopropyl, tert-butyl, etc.), cyclic (e.g., cyclohexyl, cyclopropyl, cyclopentyl, etc.), or polycyclic (e.g., norbornyl, adamantyl, etc.). These alkyl moieties may be substituted or unsubstituted.

[0032] "Halogenated alkyl" refers to a straight-chain, cyclic, or branched saturated alkyl group as defined above, wherein one or more hydrogens have been replaced by a halogen (e.g., F, Cl, Br, and I). Thus, for example, fluorinated alkyl (also known as "fluoroalkyl") refers to a straight-chain, cyclic, or branched saturated alkyl group as defined above, wherein one or more hydrogens have been replaced by fluorine (e.g., trifluoromethyl, perfluoroethyl, 2,2,2-trifluoroethyl, perfluoroisopropyl, perfluorocyclohexyl, etc.). Such a haloalkyl moiety (e.g., a fluoroalkyl moiety) may be unsubstituted or further substituted if it has not been fully halogenated / polyhalogenated.

[0033] "Alkoxy" (also known as "alkyloxy") refers to an alkyl group as defined above, which is linked via an oxygen (-O-) moiety (e.g., methoxy, ethoxy, propoxy, butoxy, 1,2-isopropoxy, cyclopentoxy, cyclohexyloxy, etc.). These alkoxy moiety may be substituted or unsubstituted.

[0034] "Alkyl carbonyl" refers to an alkyl group as defined above, which is linked via a carbonyl (-C(=O-)) moiety (e.g., methyl carbonyl, ethyl carbonyl, propyl carbonyl, butyl carbonyl, cyclopentyl carbonyl, etc.). These alkyl carbonyl moiety may be substituted or unsubstituted.

[0035] "Halo" or "halide" refers to halogens (e.g., F, Cl, Br, and I).

[0036] A hydroxyl group (also known as a hydroxyl group) is a -OH group.

[0037] Unless otherwise indicated, when referring to alkyl, alkoxy, fluorinated alkyl, etc., the term "substituted" means one of these moieties that also contains one or more substituents, including but not limited to: alkyl, substituted alkyl, unsubstituted aryl, substituted aryl, alkyloxy, alkylaryl, haloalkyl, halo, hydroxy, amino, and aminoalkyl. Similarly, the term "unsubstituted" means the same moieties in which no substituents other than hydrogen are present.

[0038] The section headings used herein are for organizational purposes and should not be construed as limiting the subject matter. All references or portions thereof cited in this application (including, but not limited to, patents, patent applications, articles, books, and papers) are expressly incorporated herein by reference in their entirety for any purpose. In the event that any of the incorporated references and similar materials defines terms in a manner that contradicts the definitions used in this application, the definitions used in this application shall prevail.

[0039] Detailed description

[0040] It should be understood that the foregoing general description and the following detailed description are illustrative and explanatory in nature, and do not limit the subject matter as claimed. Those skilled in the art will readily recognize the objectives, features, advantages, and concepts of the disclosed subject matter based on the description provided herein, and will be able to readily practice the disclosed subject matter based on the description presented herein. Descriptions of any “preferred embodiments” and / or examples illustrating preferred modes of practice for the disclosed subject matter are included for explanatory purposes, and the “preferred embodiments” and / or examples are not intended to limit the scope of the claims.

[0041] Those skilled in the art will also appreciate that various modifications can be made to how the disclosed subject matter is practiced, based on the aspects described herein, without departing from the spirit and scope of the subject matter disclosed herein.

[0042] EPL formulation

[0043] As described above, one aspect of the disclosed subject matter includes EPL materials that can be applied and removed using water-based solvents. EPL formulations comprise (i) one or more water-soluble polymers and (ii) an aqueous solvent, substantially consisting of or consisting of the above.

[0044] Importantly, when the EPL formulation is used in semiconductor processing, the resulting EPL is substantially or completely insoluble in the non-aqueous casting solvents (one or more) and / or other non-aqueous solvents (one or more) used in the relevant steps of the semiconductor process described above, but is readily soluble in water (and thus removable). Therefore, in one embodiment, the EPL forms edge beads that are (i) more than about 85% soluble in water and (ii) less than about 20% soluble in a non-aqueous solvent. In one aspect of this embodiment, the edge beads are (i) more than about 90% soluble in water and (ii) less than about 15% soluble in a non-aqueous solvent. In one aspect of this embodiment, the formed edge beads are (i) more than about 95% soluble in water and (ii) less than about 10% soluble in a non-aqueous solvent. In one aspect of this embodiment, the formed edge beads are (i) more than about 95% soluble in water and (ii) less than about 5% soluble in a non-aqueous solvent. In one aspect of this embodiment, the formed edge beads are (i) soluble in water at a concentration greater than about 99% and (ii) soluble in a non-aqueous solvent at a concentration less than about 5%. In another aspect of this embodiment, the formed edge beads are (i) soluble in water at a concentration greater than about 99% and (ii) soluble in a non-aqueous solvent at a concentration less than about 1%. In other embodiments, the EPL formulation may optionally contain, for example, surfactants for improving coating performance, dissolution promoters or inhibitors for adjusting solubility.

[0045] Water-soluble polymers

[0046] In one embodiment, one or more water-soluble polymers comprise one or more polymers having at least 90% of one or more repeating units from Table 1:

[0047]

[0048] Table 1

[0049] In one embodiment, one or more water-soluble polymers comprise one or more polymers having at least 95% of one or more repeating units from Table 1. In one embodiment, one or more water-soluble polymers comprise one or more polymers having at least 98% of one or more repeating units from Table 1. As those skilled in the art will understand, repeating units in Table 1 include structures appearing in parentheses. In one embodiment, one or more water-soluble polymers consist essentially of one or more repeating units from Table 1 (excluding end groups). In one embodiment, one or more water-soluble polymers consist essentially of one repeating unit from Table 1 (excluding end groups). In one embodiment, one or more water-soluble polymers consist of one or more repeating units from Table 1 (excluding end groups). In one embodiment, one or more water-soluble polymers consist of one repeating unit from Table 1 (excluding end groups).

[0050] In one embodiment, one or more water-soluble polymers are selected from the group consisting of: poly(4-styrenesulfonic acid), ammonium salt of poly(4-styrenesulfonic acid), polyvinyl alcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-alternative-maleic acid), and poly(vinyl phosphate). In one embodiment, one or more water-soluble polymers comprise two or more polymers selected from the group consisting of: poly(4-styrenesulfonic acid), ammonium salt of poly(4-styrenesulfonic acid), polyvinyl alcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-alternative-maleic acid), and poly(vinyl phosphate). In one embodiment, one or more water-soluble polymers comprise poly(4-styrenesulfonic acid). In one embodiment, one or more water-soluble polymers comprise ammonium salt of poly(4-styrenesulfonic acid). In one embodiment, one or more water-soluble polymers comprise polyvinyl alcohol (about 40% to about 97% hydrolyzed). In one embodiment, one or more water-soluble polymers comprise poly(acrylamide). In one embodiment, one or more water-soluble polymers comprise dextran. In one embodiment, one or more water-soluble polymers comprise poly(allylamine). In one embodiment, one or more water-soluble polymers comprise poly(methacrylic acid). In one embodiment, one or more water-soluble polymers comprise poly(methyl vinyl ether-alternative-maleic acid). In one embodiment, one or more water-soluble polymers comprise poly(vinyl phosphate).

[0051] Aqueous solvents

[0052] The disclosed and claimed cleaning EPL formulations are water-based and thus contain an aqueous solvent containing at least about 70 wt% water. The water in the aqueous solvent functions in various ways, for example, such as dissolving one or more solid components of the composition, acting as a carrier for the components, acting as an adjuvant to promote the removal of inorganic salts and complexes, acting as a viscosity modifier of the composition, and acting as a diluent. Preferably, the water used in the cleaning composition is deionized water (DIW).

[0053] In one embodiment, the aqueous solvent contains at least about 70 wt% water.

[0054] In one embodiment, the aqueous solvent contains at least about 75 wt% water.

[0055] In one embodiment, the aqueous solvent contains at least about 80 wt% water.

[0056] In one embodiment, the aqueous solvent contains at least about 85 wt% water.

[0057] In one embodiment, the aqueous solvent contains at least about 90 wt% water.

[0058] In one embodiment, the aqueous solvent contains at least about 95 wt% water.

[0059] In one embodiment, the aqueous solvent contains at least about 98 wt% water.

[0060] In one embodiment, the aqueous solvent contains at least about 99 wt% water.

[0061] In one embodiment, the aqueous solvent contains at least about 99.5 wt% water.

[0062] In one embodiment, the aqueous solvent contains at least about 100 wt% water.

[0063] Suitable aqueous solvents include, but are not limited to, water and mixtures of water-miscible organic solvents (e.g., alcohols (e.g., ethanol), ethers (e.g., THF), ketones (e.g., acetone)).

[0064] In the disclosed and claimed EPL formulations, the amount of water constitutes the weight balance of the formulation. For example, an EPL formulation having about 20 wt% of one or more water-soluble polymers and the "balance of water" has about 80 wt% water, while an EPL formulation having about 36 wt% of one or more water-soluble polymers and the "balance of water" has about 64 wt% water.

[0065] How to use

[0066] As stated above, another aspect of the disclosed and claimed subject matter includes the use of the EPL formulations described herein in semiconductor processing.

[0067] First, an EPL formulation is coated onto the wafer edge and baked to form the EPL. Here, the EPL is insoluble in the casting solvent used for depositing hard masks or metal oxide resists (MOR). Next, a metal-containing material is coated onto the wafer, and the wafer edge is cleaned with an organic solvent to remove the metal-containing material. Then, an aqueous removal solvent is used to remove the EPL from the wafer edge. Finally, the wafer is optionally baked to cure the metal-containing material. In this way, the metal-coated wafer can safely undergo photolithography and etching processes without cross-contamination.

[0068] In one embodiment, the disclosed and claimed EPL formulation is used in a semiconductor manufacturing process, comprising one or more steps selected from the group consisting of:

[0069] (a) Apply one or more of the EPL formulations disclosed and claimed herein to the edge of a wafer or substrate and at least one adjacent surface;

[0070] (b) Heating one or more of the applied EPL formulation to form an edge protection layer on the edge of the wafer or substrate and at least one adjacent surface.

[0071] (c) Applying a metal-containing composition to a wafer or substrate and an edge protection layer;

[0072] (d) Remove at least a portion of the applied metal-containing composition that is in contact with the edge protective layer;

[0073] (e) Heating the applied metal-containing composition to form a metal-based functional film;

[0074] (f) Remove the edge protection layer using an aqueous removal solvent; and

[0075] (g) Optionally, bake after at least one application.

[0076] In one aspect of this embodiment, the aqueous removal solvent comprises, is substantially composed of, or is composed of water. In another aspect of this embodiment, the aqueous removal solvent is the same as or substantially the same as the aqueous solvent of the EPL formulation.

[0077] Example

[0078] Reference will now be made to more specific embodiments of the invention and experimental results supporting such embodiments. Examples are given below to more fully illustrate the disclosed subject matter and should not be construed as limiting the disclosed subject matter in any way.

[0079] Those skilled in the art will appreciate that various modifications and variations can be made to the disclosed subject matter and specific embodiments provided herein without departing from the spirit or scope of the disclosed subject matter. Therefore, the disclosed subject matter (including the description provided by the following embodiments) is intended to cover modifications and variations of the disclosed subject matter that appear within the scope of any claims and their equivalents.

[0080] Materials and methods:

[0081] AZ MHM1001J2N is a spin-coated zirconium hard mask available from EMD Electronics. The ArF viscosity reducer is a PGMEA / PGME 70 / 30 (wt / wt) mixed solvent available from EMD Electronics.

[0082] Example 1-1 (Poly(4-styrenesulfonic acid))

[0083] Dilute 22.2 g of 18% poly(4-styrenesulfonic acid) (Mw 75,000 aqueous solution) with 17.8 g of deionized water to form a 10% poly(4-styrenesulfonic acid) solution.

[0084] Examples 1-2 (Poly(4-styrenesulfonic acid)): Sodium salt conversion

[0085] 10 g of a 25% sodium poly(4-styrenesulfonic acid) solution and 17.5 g of deionized water were mixed to form a 9% sodium poly(4-styrenesulfonic acid) solution. This solution was then converted by ion exchange (Amberlyst™ A15) to produce a 4.8% sodium poly(4-styrenesulfonic acid) (Mw 1,000,000) solution.

[0086] Examples 1-3 (Poly(4-styrenesulfonic acid))

[0087] 10 g of a 10% sodium poly(4-styrenesulfonic acid) salt aqueous solution and 10.8 g of deionized water were mixed and converted by ion exchange (Amberlyst™ A15) to produce a 4.8% poly(4-styrenesulfonic acid) (Mw 200,000) aqueous solution, as prepared in Examples 1-2.

[0088] Example 2 (Poly(4-styrenesulfonate)ammonium salt)

[0089] Dilute 10 g of 30% poly(4-styrenesulfonic acid) ammonium salt (Mw 200,000 aqueous solution) with 20 g of deionized water to form a 10% poly(4-styrenesulfonic acid) ammonium salt solution.

[0090] Example 3-1 (Polyvinyl alcohol)

[0091] Dissolve 4 g of polyvinyl alcohol (40% hydrolyzed; Mw 9,000-10,000) in 36 g of deionized water to form a 10% polyvinyl alcohol solution.

[0092] Example 3-2 (Polyvinyl alcohol)

[0093] Dissolve 4 g of polyvinyl alcohol (97-90% hydrolyzed; Mw 30,000-70,000) in 36 g of deionized water to form a 10% polyvinyl alcohol solution.

[0094] Example 3-3 (Polyvinyl alcohol)

[0095] 4 g of polyvinyl alcohol (87-89% hydrolyzed; Mw 1,800) was dissolved in 36 g of deionized water to form a 10% polyvinyl alcohol solution.

[0096] Example 4 (Poly(acrylamide))

[0097] Dissolve 4 g of poly(acrylamide) (Mw 40,000) in 36 g of deionized water to form a 10% poly(acrylamide) solution.

[0098] Example 5 (Dextran)

[0099] Dissolve 4 g of dextran (Mw 9,000-11,000) in 36 g of deionized water to form a 10% dextran solution.

[0100] Example 6 (Poly(allylamine) solution)

[0101] Dilute 10 g of 20% poly(allylamine) solution (Mw 15,000) with 10 g of deionized water to form a 10% poly(allylamine) solution.

[0102] Example 7 (Poly(methacrylic acid))

[0103] 10 g of 10% sodium poly(methacrylic acid) solution (Mw 9,500) and 8.18 g of deionized water were mixed and converted by ion exchange (Amberlyst™ A15) to produce a 5.5% poly(methacrylic acid) solution.

[0104] Example 8 (Poly(methyl vinyl ether-alternating-maleic acid))

[0105] 4 g of poly(methyl vinyl ether-alternative-maleic acid) (Mw 216,000) was dissolved in 36 g of deionized water to form a 10% poly(methyl vinyl ether-alternative-maleic acid) solution.

[0106] Example 9 (Poly(vinylphosphonic acid))

[0107] Dissolve 4 g of poly(vinyl phosphate) in 36 g of deionized water to form a 10% poly(vinyl phosphate) solution.

[0108] Comparative Examples

[0109] The polymers used in the following comparative examples comprise repeating units from Table 2 and are further described in each comparative example.

[0110]

[0111] Table 2

[0112] Comparative Example 1 (Polyacrylic Acid)

[0113] Dissolve 4 g of polyacrylic acid (Mw 1,800) in 36 g of deionized water to form a 10% polyacrylic acid solution.

[0114] Comparative Example 2 (2-Hydroxyethylcellulose)

[0115] 4 g of 2-hydroxyethyl cellulose (Mw 90,000) was dissolved in 96 g of deionized water to form a 4% 2-hydroxyethyl cellulose solution.

[0116] Comparative Example 3 (poly(N-isopropylacrylamide), PNIPAM)

[0117] 4 g of poly(N-isopropylacrylamide) (“PNIPAM”; Mw 40,000) was dissolved in 36 g of deionized water to form a 10% poly(N-isopropylacrylamide) solution.

[0118] Comparative Example 4 (poly(2-ethyl-2-oxazoline))

[0119] 4 g of poly(2-ethyl-2-oxazoline) (Mw 50,000) was dissolved in 36 g of deionized water to form a 10% poly(2-ethyl-2-oxazoline) solution.

[0120] Comparative Example 5 (Sodium poly(styrene-alternating-maleic acid) salt)

[0121] Dilute 10 g of 13% sodium poly(styrene-alternative-maleic acid) (Mw 350,000) with 55 g of deionized water to form a 2% sodium poly(styrene-alternative-maleic acid) solution.

[0122] Comparative Example 6 (poly(styrene-alternating-maleic acid))

[0123] As in Examples 1-2, 30 g of a 4.3% aqueous solution of sodium poly(styrene-alternative-maleic acid) (Mw 350,000) was ion-exchanged using Amberlyst™ A15 to produce a 2.3% aqueous solution of poly(styrene-alternative-maleic acid) (Mw 350,000).

[0124] Comparative Example 7 (Poly(vinylsulfonic acid), PVSA)

[0125] 10 g of 15% sodium poly(vinyl sulfonate) salt (“PVSA”; Mw 15,000) aqueous solution and 9.2 g of deionized water were mixed and converted by ion exchange (Amberlyst™ A15) to produce a 7.8% poly(vinyl sulfonate) solution.

[0126] Solubility evaluation

[0127] Formulations from Examples 1-9 and Comparative Examples 1-7 were spin-coated onto 8-inch Si wafers and baked at 100°C for 60 seconds using a TokyoElectron Act 8 Clean track (TEL Act 8). Film thickness was measured on cross-sectional images using SEM. Each wafer was immersed in AZ ArF anti-tack agent or deionized water for 60 seconds and then spin-dried. The results are summarized in Table 3. In Tables 3 and 4, the solubility percentage (“% Sol.”) is calculated as a percentage of the initial thickness of the deposited edge beads and the thickness after exposure to the ArF anti-tack agent, which is commonly used as a casting solvent for resists, spin-coated hard masks, etc. For example, in Example 1, after immersion in the ArF anti-tack agent for 60 seconds, 467 nm of the initial 480 nm edge beads remained (i.e., 97.3% of the initial thickness remained), corresponding to a solubility of 2.7%. The solubility percentage in water was calculated in the same manner.

[0128] In contrast, as shown in Tables 3 and 4, the formulations from Comparative Examples 1, 3, 4, 5, 6, and 7 are soluble in the ArF thickener and cannot be used to protect materials. The formulation from Comparative Example 2 is insoluble in the ArF thickener, but due to its poor solubility, it cannot be easily removed with deionized water. Therefore, the formulation from Comparative Example 2 also cannot be used to protect materials.

[0129]

[0130] Table 3

[0131]

[0132] Table 4

[0133] As can be seen from the data above, suitable water-soluble polymers are those that produce edge beads with (i) a solubility in water greater than about 85% and (ii) a solubility in organic-based EBR less than about 20%. Preferably, water-soluble polymers are those that produce edge beads with (i) a solubility in water greater than about 90% and (ii) a solubility in organic-based EBR less than about 15%. More preferably, water-soluble polymers are those that produce edge beads with (i) a solubility in water greater than about 95% and (ii) a solubility in organic-based EBR less than about 10%. Most preferably, water-soluble polymers are those that produce edge beads with (i) a solubility in water greater than about 95% and (ii) a solubility in organic-based EBR less than about 5%.

[0134] Protective testing against metal contamination

[0135] The formulations from Examples 1-3 were coated onto 8-inch Si wafers and baked at 100°C for 60 seconds using TEL Act 8. A zirconium hard mask (EMD Electronics, AZ MHM1001J2N) was spin-coated onto the deposited film at 1500 rpm without baking. Next, each wafer was immersed in AZ EBR7030 for 60 seconds to remove the spin-coated Zr hard mask and then spin-dried. Subsequently, each wafer was immersed in deionized water for 60 seconds, spin-dried, and then immersed in deionized water for 60 seconds, followed by spin-drying. In Comparative Example 7, AZ MHM1001J2N was directly coated onto the Si wafer, but without any of the formulations from Examples 1-3.

[0136] The Zr content on Si wafers was measured using TXRF and summarized in Table 5, with explanations provided below. Figure 3 In comparison, as can be seen from Comparative Example 7, the residual Zr on the Si wafer directly coated with the hard mask is approximately 6900 × 10⁻⁶. 10 atoms / cm 2 In contrast, the use of the disclosed and claimed EPL formulation results in a significant, multi-fold reduction in residual Zr on the Si wafer (i.e., from about 130 to about 2300 × 10⁻⁶). 10 atoms / cm 2 This allows for better protection of Si wafers from metal contamination.

[0137]

[0138] Table 5

[0139] Although the disclosed and claimed subject matter has been described and illustrated with a degree of specificity, it should be understood that this disclosure is made only by means of embodiments, and that those skilled in the art may make various changes to the conditions and order of steps without departing from the spirit and scope of the disclosed and claimed subject matter.

Claims

1. An edge protection layer (EPL) formulation comprising (i) one or more water-soluble polymers and (ii) an aqueous solvent, substantially composed of or consisting of the polymers, wherein the EPL formed therefrom is (a) substantially or completely insoluble in a non-aqueous solvent and (b) soluble in water.

2. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility in water greater than about 85% and (ii) has a solubility in a non-aqueous solvent less than about 20%.

3. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility in water greater than about 90% and (ii) has a solubility in a non-aqueous solvent less than about 15%.

4. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility in water greater than about 95% and (ii) has a solubility in a non-aqueous solvent less than about 10%.

5. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility in water greater than about 95% and (ii) has a solubility in a non-aqueous solvent less than about 5%.

6. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility in water greater than about 99% and (ii) has a solubility in a non-aqueous solvent less than about 5%.

7. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility in water greater than about 99% and (ii) has a solubility in a non-aqueous solvent less than about 1%.

8. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility greater than about 85% in the aqueous solvent and (ii) has a solubility less than about 20% in a non-aqueous solvent.

9. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility greater than about 90% in the aqueous solvent and (ii) has a solubility less than about 15% in a non-aqueous solvent.

10. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility of more than about 95% in the aqueous solvent and (ii) has a solubility of less than about 10% in a non-aqueous solvent.

11. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility greater than about 95% in the aqueous solvent and (ii) has a solubility less than about 5% in a non-aqueous solvent.

12. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility greater than about 99% in the aqueous solvent and (ii) has a solubility less than about 5% in a non-aqueous solvent.

13. The EPL formulation according to claim 1, wherein the formed EPL (i) has a solubility greater than about 99% in the aqueous solvent and (ii) has a solubility less than about 1% in a non-aqueous solvent.

14. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise one or more polymers having at least 90% of one or more repeating units from Table 1 that do not contain end groups: Table 1.

15. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise one or more polymers having at least 95% of one or more repeating units from Table 1 that do not contain end groups.

16. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise one or more polymers having at least 98% of one or more repeating units from Table 1 that do not contain end groups.

17. The EPL formulation of claim 1, wherein the one or more water-soluble polymers are substantially composed of one or more repeating units from Table 1 that do not contain end groups.

18. The EPL formulation of claim 1, wherein the one or more water-soluble polymers consist of one or more repeating units from Table 1 that do not contain end groups.

19. The EPL formulation of claim 1, wherein the one or more water-soluble polymers are substantially composed of a repeating unit from Table 1 that does not contain end groups.

20. The EPL formulation of claim 1, wherein the one or more water-soluble polymers are composed of a unit from Table 1 that does not contain end groups.

21. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise one or more of the following: poly(4-styrenesulfonic acid), poly(4-styrenesulfonic acid) ammonium salt, polyvinyl alcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-alternative-maleic acid), and poly(vinyl phosphate).

22. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise two or more of the following: poly(4-styrenesulfonic acid), poly(4-styrenesulfonic acid) ammonium salt, polyvinyl alcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-alternative-maleic acid), and poly(vinyl phosphate).

23. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise poly(4-styrenesulfonic acid).

24. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise ammonium poly(4-styrenesulfonate).

25. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise polyvinyl alcohol (about 40% to about 97% hydrolyzed).

26. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise poly(acrylamide).

27. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise dextran.

28. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise poly(allylamine).

29. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise poly(methacrylic acid).

30. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise poly(methyl vinyl ether-alternating-maleic acid).

31. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise poly(vinyl phosphate).

32. The EPL formulation of claim 1, wherein the aqueous solvent is substantially composed of water.

33. The EPL formulation of claim 1, wherein the aqueous solvent is composed of water.

34. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 70 wt% water.

35. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 75 wt% water.

36. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 80 wt% water.

37. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 85 wt% water.

38. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 90 wt% water.

39. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 95 wt% water.

40. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 98 wt% water.

41. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 99 wt% water.

42. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 99.5 wt% water.

43. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise at least one water-miscible organic solvent.

44. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise at least one water-miscible organic solvent selected from the group consisting of alcohols, ethers and ketones.

45. The EPL formulation of claim 1, wherein the one or more water-soluble polymers comprise at least one water-miscible organic solvent selected from the group consisting of ethanol, THF and acetone.

46. ​​A semiconductor manufacturing method, comprising the following steps: (a) Applying one or more of the EPL formulations according to any one of claims 1 to 45 to the edge of a wafer or substrate and at least one adjacent surface. (b) Heating one or more of the applied EPL formulation to form an edge protection layer on the edge of the wafer or substrate and at least one adjacent surface. (c) Applying a metal-containing composition to the wafer or substrate and the edge protection layer; (d) Remove at least a portion of the applied metal-containing composition that is in contact with the edge protective layer; (e) Heating the applied metal-containing composition to form a functional film based on the metal; (f) Remove the edge protection layer using an aqueous removal solvent; and (g) Optionally, bake after at least one application.

47. The method of claim 46, wherein the aqueous removal solvent comprises water, is substantially composed of or is composed of water.

48. The method of claim 46, wherein the aqueous removal solvent is the same as or substantially the same as the aqueous solvent of the EPL formulation.

Images