Lithography compositions and methods of use thereof for sustainable and greener solutions for edge protection layers

Abstract

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

Description

Docket No. P23-168 -WO-PCT LITHOGRAPHY COMPOSITIONS AND METHODS OF USE THEREOF FOR SUSTAINABLE AND GREENER SOLUTIONS FOR EDGE PROTECTION LAYERS

[0001] BACKGROUND

[0002] Field

[0003] The disclosed subject matter relates to water-soluble wafer edge protection layer (EPL) material for a sustainable / greener solution for semiconductor processing.

[0004] Related Art

[0005] Multiple antireflective layers and hardmasks are used in advanced lithographic patterning processes. For example, in cases where a photoresist does not provide enough dry etch resistance, underlayers and / or antireflective coatings for the photoresist that act as a hardmask and are highly etch resistant during substrate etching are preferred. One approach has been to incorporate silicon, titanium, zirconium, aluminum or other metallic materials into a layer beneath the organic photoresist layer. Additionally, another high carbon content antireflective or mask layer may be placed beneath the metal containing antireflective layer to create a tri-layer of high carbon film / hard mask film / photoresist. Such layers can be used to improve the lithographic performance of the imaging process. However, metal contamination in the lithographic and etch tools, as well as cross contamination between wafers during manufacturing, can be problems that should be avoided. These issues are becoming increasingly important for spin-on metal hard mask and metal based EUV resists being introduced to next generation device manufacturing technology where cleanliness of the wafer edge is especially important.

[0006] One process and apparatus for reducing metal contamination during the manufacture of integrated circuit components has been described in U.S. Patent No.8,791,030 (“Iwao”), which is hereby incorporated herein in its entirety. According to Iwao, a masking agent is supplied to an edge of the wafer / substrate and baked to form a masking film (a.k.a. an edge protection layer (“EPL”) or edge masking layer) at the edge of the wafer / substrate. A hardmask composition is then coated on the wafer / substrate and the EPL. The portion of the hardmask composition overlying the edge protection layer is removed using an edge bead remover (“EBR”) and the hardmask composition is baked to form a hardmask. The EPL is then removed with an EPL removing solution. The result is a hardmask that is spaced away from the edge of the wafer / substrate, thereby reducing contamination.

[0007] Masking agents forming EPLs are described in patent application PCT / EP2018 / 056322 (published as WO / 2018 / 167112) entitled “Lithographic Compositions and Methods of Use Thereof,” which is incorporated herein by reference in its entirety. The compositions disclosed therein prevent metal contamination at substrate / wafer edges duringDocket No. P23-168-WO-PCT the manufacture of electronic devices. As explained in PCT / EP2018 / 056322, it is desirable that the applied EPLs be able to be readily removed at rates enabling and / or maintaining commercially acceptable process times without having a negative or damaging effect on the hardmask (such as can occur by wet etching).

[0008] PCT / EP2018 / 056322 further sets forth a general process for applying a masking agent to form an EPL in a method for manufacturing an electronic device as is illustrated in FIGs 2 a-f, herein. In such a process, a metal hardmask composition or metal oxide photoresist composition (collectively a “hardmask” or “hardmask composition”) is applied onto the substrate and the EPL (see FIG.2c). The EPL and the hardmask composition are then rinsed with an EBR and / or a backside rinse (“BR”) material to remove at least a portion of the hardmask composition that is in contact with the EPL (see FIG.2d). A portion or portions of the hardmask composition in contact with the EPL may nevertheless remain even after rinsing with an EBR or BR. The hardmask composition can, for example, partially penetrate through the EPL or undercut the edge thereof. Consequently, some quantity of the hardmask and / or its components in contact with the EPL may not be removed during the EBR rinse. To date, no compositions or processes / method have been identified providing for the simultaneous removal of both the EPL and the remaining residual components (e.g., metals) of the hardmask. Instead, the step of removing the EPL must be followed by a subsequent processing step (e.g., rinsing with additional EBR) in which any remaining residual components of the hardmask are removed from the edge and proximate surfaces of the wafer / substrate. This additional step is both costly and time consuming, and thus inconsistent with enabling and / or maintaining commercially acceptable process times when an EPL is utilized.

[0009] Notably, in the above-described process (and in other known processes) a nonaqueous, organic solvent is used to apply EPL in order to avoid metal contamination of wafers when spin-on metal hardmask or metal oxide resists (MORs) are used. In such processes, the EPL is not soluble in the non-aqueous, organic casting solvent used for depositing the hardmask or metal oxide resists (MORs). Next, the wafer edge is cleaned with the casting solvent to remove any metal containing material on the wafer edge. Then, the EPL material on the wafer edge is removed with a nonaqueous solvent (which may be the same or substantially same solvent used to deposit the EPL). Finally, the wafer is baked to cure metal containing material. In this way, the metal containing material coated wafer safely go through the lithography and etch processes without causing cross-contamination.

[0010] As can be seen from the above, the application and removal of EBRs requires using significant amounts of organic solvent. This is not only expensive (owing to the high costs of the organic solvents utilized) but also an environmental hazard. Thus, there is a needDocket No. P23-168-WO-PCT and desire 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 an EPL material that can be applied and removed with aqueous solvent instead of organic solvent-based remover. Since the process uses an aqueous solvent, the liquid waste treatment is both cost effective environmentally friendly and therefore provides and sustainable and green solution for semiconductor processing. The disclosed and claimed EPL system includes water-soluble polymers and an aqueous solvent as its major components. It is spin coatable on substrates and, after baking, it is insoluble in the casting solvent of metal containing materials. In addition, the EPL is removable with aqueous remover solvent. Thus, the disclosed and claimed subject matter is directed to these sustainable and green EPL systems as well as their methods of use.

[0012] SUMMARY

[0013] In one aspect, the disclosed subject matter includes EPL formulations that are capable of being applied and removed with water-based (i.e., aqueous) solvents where the EPL formulations include, consist essentially of or consist of a water-soluble polymer and water as major components.

[0014] In another aspect, the disclosed and claimed subject matter includes the use of the EPL formulations described herein.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

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

[0017] FIG.1 illustrates a cross section of a wafer / substrate edge upon which an EPL is applied;

[0018] FIGs.2a-f illustrate a schematic representation of one embodiment of a method and process for using the rinse solutions disclosed herein. In FIG.2a, a masking agent is applied onto an edge of a substrate. In FIG.2b, the masking agent is heated to form an EPL. In FIG.2c, a hardmask composition is applied onto the substrate and the EPL. In FIG.2d, the hardmask composition and EPL are rinsed with an EBR to remove at least a portion of the hardmask composition that is in contact with the EPL. In FIG.2e, the hardmask composition is heated to form a hardmask. In FIG.2f, the EPL and residual hardmask components (e.g., metals such as tin or titanium) are removed from the edge of a wafer / substrate with the rinse; and

[0019] FIG.3 illustrates the residual Zr on an Si wafer measured with TXRF (units of 1010atoms / cm2) for Examples 1A, 1, 2, 3 and Comparative Example 1.Docket No. P23-168-WO-PCT

[0020] DEFINITIONS

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

[0022] In this application, the use of the singular includes the plural, and the words “a,” “an” and “the” mean “at least one” unless specifically stated otherwise. Furthermore, the use of the term “including,” as well as other forms such as “includes” and “included,” is not limiting. Also, terms such as “element” or “component” encompass both elements or components including one unit and elements or components that include more than one unit, unless specifically stated otherwise. As used herein, the conjunction “and” is intended to be inclusive and the conjunction “or” is not intended to be exclusive, unless otherwise indicated. 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 using 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” 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” also includes 0.0 wt%. The term “free of” means 0.0 wt% as commonly 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, an “aqueous solvent” is a solvent that includes at least about 70 wt% of 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% of water and most preferably at least about 99 wt% of water. An “aqueous solvent” also includes water absent the presence of other solvents, i.e., water that is substantially free and / or free of other solvents.

[0027] As used herein, a “nonaqueous solvent” is a solvent that includes no more than about 10 wt% of water, more preferably no more than about 5 wt% of water and most preferably no more than about 1 wt% of water. A “nonaqueous solvent” also includes solvents that include little or no water absent the presence of other solvents, i.e., a solvent that is substantially free and / or free of water.

[0028] As used herein, an “aqueous remover solvent” is a solvent that includes at least about 70 wt% of 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% of water and most preferably at least about 99 wt% of water. An “aqueous removerDocket No. P23-168-WO-PCT solvent” also includes water absent the presence of other solvents, i.e., water that is substantially free and / or free of other solvents.

[0029] In compositions “consisting essentially of” recited components, such components may add up to 100 weight % of the composition or may add up to less than 100 weight % (“wt%”). Where the components add up to less than 100 weight %, such composition may include some small amounts of a non-essential contaminants or impurities. For example, in one such embodiment, the cleaning composition can contain 2% by weight or less of impurities. In another embodiment, the cleaning composition can contain 1% by weight or less than of impurities. In a further embodiment, the cleaning composition can contain 0.05% by weight or less than of impurities. In other such embodiments, the ingredients can 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 can include other ingredients that do not material affect the performance of the cleaning compositions. Otherwise, if no significant non-essential impurity component is present, it is understood that the combination of all essential constituent components will essentially add up to 100 weight %.

[0030] As used herein, “Cx-y” designates the number of carbon atoms in a chain. For example, C1-6alkyl refers to an alkyl chain having a chain of between 1 and 6 carbons (e.g., methyl, ethyl, propyl, butyl, pentyl and hexyl). Unless specifically stated otherwise, the chain can be linear or branched.

[0031] Unless otherwise indicated, “alkyl” refers to hydrocarbon groups which can be linear, branched (e.g., methyl, ethyl, propyl, isopropyl, tert-butyl and the like), cyclic (e.g., cyclohexyl, cyclopropyl, cyclopentyl and the like) or multicyclic (e.g., norbornyl, adamantly and the like). These alkyl moieties may be substituted or unsubstituted.

[0032] “Halogenated alkyl” refers to a linear, cyclic or branched saturated alkyl group as defined above in which one or more of the hydrogens has been replaced by a halogen (e.g., F, Cl, Br and I). Thus, for example, a fluorinated alkyl (a.k.a. “fluoroalkyl”) refers to a linear, cyclic or branched saturated alkyl group as defined above in which one or more of the hydrogens has been replaced by fluorine (e.g., trifluoromethyl, pefluoroethyl, 2,2,2-trifluoroethyl, prefluoroisopropyl, perfluorocyclohexyl and the like). Such haloalkyl moieties (e.g., fluoroalkyl moieties), if not perhalogenated / multihalogentated, may be unsubstituted or further substituted.

[0033] “Alkoxy” (a.k.a. “alkyloxy”) refers to an alkyl group as defined above which is attached through an oxy (-O-) moiety (e.g., methoxy, ethoxy, propoxy, butoxy, 1,2-isopropoxy, cyclopentyloxy, cyclohexyloxy and the like). These alkoxy moieties may be substituted or unsubstituted.Docket No. P23-168-WO-PCT

[0034] “Alkyl carbonyl” refers to an alkyl group as defined above which is attached through a carbonyl group (-C(=O-)) moiety (e.g., methylcarbonyl, ethylcarbonyl, propylcarbonyl, buttylcarbonyl, cyclopentylcarbonyl and the like). These alkyl carbonyl moieties may be substituted or unsubstituted.

[0035] “Halo” or “halide” refers to a halogen (e.g., F, Cl, Br and I).

[0036] “Hydroxy” (a.k.a. “hydroxyl”) refers to an –OH group.

[0037] Unless otherwise indicated, the term “substituted” when referring to an alkyl, alkoxy, fluorinated alkyl and the like refers to one of these moieties which also contains one or more substituents including, but not limited, to the following substituents: alkyl, substituted alkyl, unsubstituted aryl, substituted aryl, alkyloxy, alkylaryl, haloalkyl, halide, hydroxy, amino and amino alkyl. Similarly, the term “unsubstituted” refers to these same moieties where no substituents apart from hydrogen are present.

[0038] The section headings used herein are for organizational purposes and are not to be construed as limiting the subject matter described. All documents, or portions of documents, cited in this application, including, but not limited to, patents, patent applications, articles, books, and treatises, are hereby expressly incorporated herein by reference in their entirety for any purpose. In the event that any of the incorporated literature and similar materials defines a term in a manner that contradicts the definition of that term in this application, this application controls.

[0039] DETAILED DESCRIPTION

[0040] It is to be understood that both the foregoing general description and the following detailed description are illustrative and explanatory, and are not restrictive of the subject matter, as claimed. The objects, features, advantages and ideas of the disclosed subject matter will be apparent to those skilled in the art from the description provided in the specification, and the disclosed subject matter will be readily practicable by those skilled in the art on the basis of the description appearing herein. The description of any “preferred embodiments” and / or the examples which show preferred modes for practicing the disclosed subject matter are included for the purpose of explanation and are not intended to limit the scope of the claims.

[0041] It will also be apparent to those skilled in the art that various modifications may be made in how the disclosed subject matter is practiced based on described aspects in the specification without departing from the spirit and scope of the disclosed subject matter disclosed herein.

[0042] EPL Formulations

[0043] As noted above, one aspect the disclosed subject matter includes EPL materials that are capable of being applied and removed with water-based solvents. The EPL formulations include, consist essentially of or consist of (i) one or more water-soluble polymerDocket No. P23-168-WO-PCT and (ii) an aqueous solvent.

[0044] Importantly, when the EPL formulation is used in semiconductor processing, it produces an EPL that is substantially or entirely insoluble in the nonaqueous casting solvent(s) and / or other nonaqueous solvent(s) used in the relevant steps of the semiconductor processes described above and are instead readily soluble (and therefore removeable) with water. As such, in one embodiment, the EPL forms an edge bead that is (i) greater than about 85% soluble in water and (ii) less than about 20% soluble in nonaqueous solvent. In one aspect of this embodiment, the edge bead is (i) greater than about 90% soluble in water and (ii) less than about 15% soluble in nonaqueous solvent. In one aspect of this embodiment, the formed edge bead is (i) greater than about 95% soluble in water and (ii) less than about 10% soluble in nonaqueous solvent. In one aspect of this embodiment, the formed edge bead is (i) greater than about 95% soluble in water and (ii) less than about 5% soluble in nonaqueous solvent. In one aspect of this embodiment, the formed edge bead is (i) greater than about 99% soluble in water and (ii) less than about 5% soluble in nonaqueous solvent. In one aspect of this embodiment, the formed edge bead is (i) greater than about 99% soluble in water and (ii) less than about 1% soluble in nonaqueous solvent. In other embodiments, the EPL formulations may optionally include ingredients, such as surfactants for improving coating performance, dissolution promoters or inhibitors for adjusting solubility.

[0045] Water Soluble Polymers

[0046] In one embodiment, the one or more water-soluble polymer includes one or more polymers having at least 90% of one or more repeat units from Table 1: OH O S O O S O OH(iii) ONH4(i) (ii) O O NH O2C NH2HO OH CH3OH (iv) (v) (vi)Docket No. P23-168-WO-PCT O CO O 2H C OH HO P OH CH3OCH3CO2H(vii) (viii) (ix)

[0047] In one embodiment, the one or more water-soluble polymer includes one or more polymers having at least 95% of one or more repeat units from Table 1. In one embodiment, the one or more water-soluble polymer includes one or more polymers having at least 98% of one or more repeat units from Table 1. As those skilled in the art will understand, in Table 1 the repeat units include the structure appearing within the bracket. In one embodiment, the one or more water-soluble polymer consists essentially of one or more repeat unit from Table 1 (not including end groups). In one embodiment, the one or more water- soluble polymer consists essentially of one repeat unit from Table 1 (not including end groups). In one embodiment, the one or more water-soluble polymer consists of one or more repeat unit from Table 1 (not including end groups). In one embodiment, the one or more water-soluble polymer consists of one repeat unit from Table 1 (not including end groups).

[0048] In one embodiment, the one or more water-soluble polymer is selected from the group of poly(4-stylenesulfonic acid), poly(4-styrene sulfonic acid)ammonium salt, polyvinylalcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-alt-maleic acid) and poly(vinylphosphoric acid). In one embodiment, the one or more water-soluble polymer includes two or more polymers selected from the group of poly(4-stylenesulfonic acid), poly(4-styrene sulfonic acid)ammonium salt, polyvinylalcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-alt- maleic acid) and poly(vinylphosphoric acid). In one embodiment, the one or more water-soluble polymer includes poly(4-stylenesulfonic acid). In one embodiment, the one or more water-soluble polymer includes poly(4-styrene sulfonic acid)ammonium salt. In one embodiment, the one or more water-soluble polymer includes polyvinylalcohol (about 40% to about 97% hydrolyzed). In one embodiment, the one or more water-soluble polymer includes poly(acrylamide). In one embodiment, the one or more water-soluble polymer includes dextran. In one embodiment, the one or more water-soluble polymer includes poly(allylamine). In one embodiment, the one or more water-soluble polymer includes poly(methacrylic acid). In one embodiment, the one or moreDocket No. P23-168-WO-PCT water-soluble polymer includes poly(methyl vinyl ether-alt-maleic acid). In one embodiment, the one or more water-soluble polymer includes poly(vinylphosphoric acid).

[0049] Aqueous Solvent

[0050] The disclosed and claimed cleaning EPL formulations are aqueous-based and, thus, include and aqueous solvent that includes at least about 70 wt% of aqueous solvent. The water in the aqueous solvent functions in various ways such as, for example, to dissolve one or more solid components of the composition, as a carrier of the components, as an aid to facilitate the removal of inorganic salts and complexes, as a viscosity modifier of the composition, and as a diluent. Preferably, the water employed in the cleaning compositions is deionized water (DIW) water.

[0051] In one embodiment the aqueous solvent includes at least about 70 wt% of water.

[0052] In one embodiment the aqueous solvent includes at least about 75 wt% of water.

[0053] In one embodiment the aqueous solvent includes at least about 80 wt% of water.

[0054] In one embodiment the aqueous solvent includes at least about 85 wt% of water.

[0055] In one embodiment the aqueous solvent includes at least about 90 wt% of water.

[0056] In one embodiment the aqueous solvent includes at least about 95 wt% of water.

[0057] In one embodiment the aqueous solvent includes at least about 98 wt% of water.

[0058] In one embodiment the aqueous solvent includes at least about 99 wt% of water.

[0059] In one embodiment the aqueous solvent includes at least about 99.5 wt% of water.

[0060] In one embodiment the aqueous solvent includes at least about 100 wt% of water.

[0061] Suitable aqueous solvents include, but are not limited to, mixtures of water and water-miscible organic solvents such alcohols (e.g., ethanol), ethers (e.g., THF), ketones (e.g., acetone).

[0062] In the disclosed and claimed EPL formulations, the amount of water constitutes the weighted balance of the formulations. For example, an EPL formulation having about 20 wt% of the one or more water-soluble polymer and an “balance of water” would have about 80 wt% of water whereas an EPL formulation having about 36 wt% of the one or more water- soluble polymer and an “balance of water” would have about 64 wt% of water.

[0063] Methods of Use

[0064] As noted above, another aspect of the disclosed and claimed subject matter includes the use of the EPL formulations described herein in semiconductor processing.

[0065] First the EPL formulation is coated on the wafer edge and baked to form an EPL. Here the EPL is not soluble in the casting solvent used for depositing the hardmask or metal oxide resists (MORs). Next a metal containing material is coated on the wafer, and the wafer edge is cleaned with an organic solvent to remove the metal containing material on the wafer edge. Then,Docket No. P23-168-WO-PCT the EPL on the wafer edge is removed with aqueous remover solvent. Finally, the wafer is optionally baked to cure metal containing material. In this way, the metal containing material coated wafer safely go through the lithography and etch processes without causing cross-contamination.

[0066] In one embodiment, the disclosed and claimed EPL formulations are used in a semiconductor manufacturing process that includes one or more steps selected from the group of: (a) applying one or more of the EPL formulations disclosed and claimed herein on an edge and at least one proximate surface of a wafer or substrate; (b) heating the applied one or more of the EPL formulations to form an edge protection layer on the edge and at least one proximate surface of the wafer or substrate; (c) applying a metal containing composition to the wafer or substrate and the edge protection layer; (d) removing at least a portion of the applied metal containing composition that is in contact with the edge protection layer; (e) heating the applied metal containing composition to form the metal based functional film; (f) removing the edge protection layer with an aqueous remover solvent; and (g) optionally performing at least one post applied bake. In one aspect of this embodiment, the aqueous remover solvent includes, consists essentially of or consists of water. In another aspect of this embodiment the aqueous remover solvent is the same or substantially the same as the as the aqueous solvent of the EPL formulation.

[0067] EXAMPLES

[0068] Reference will now be made to more specific embodiments of the present disclosure and experimental results that provide support for such embodiments. The 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.

[0069] It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosed subject matter and specific examples provided herein without departing from the spirit or scope of the disclosed subject matter. Thus, it is intended that the disclosed subject matter, including the descriptions provided by the following examples, covers the modifications and variations of the disclosed subject matter that come within the scope of any claims and their equivalents.

[0070] Materials and Methods:

[0071] AZ MHM1001J2N is a spin on Zirconium hardmask available from EMD Electronics. ArF Thinner is a PGMEA / PGME 70 / 30 (wt / wt) mixed solvent available fromDocket No. P23-168-WO-PCT EMD Electronics.

[0072] Example 1-1 (Poly(4-styrenesulfonic acid))

[0073] 22.2 g of 18% poly(4-syrenesulfonic acid) (Mw 75,000 aqueous solution) was diluted with 17.8 g of deionized water to form a 10% poly(4-syrenesulfonic acid) solution.

[0074] Example 1-2 (Poly(4-styrenesulfonic acid)): Sodium Salt Conversion

[0075] 10 g of 25% sodium salt of poly(4-styrene sulfonic acid) aqueous solution and 17.5 g of deionized water were mixed to form a 9% sodium salt of poly(4-styrene sulfonic acid) solution. This solution was covered by way of ion exchange (Amberlyst™ A15) to yield a 4.8% poly(4-syrenesulfonic acid) (Mw 1,000,000) aqueous solution.

[0076] Example 1-3 (Poly(4-styrenesulfonic acid))

[0077] 10 g of 10% sodium salt of poly(4-syrenesulfonic acid) aqueous solution and 10.8 g of deionized water were mixed and converted by way of ion exchange (Amberlyst™ A15) to yield a 4.8% poly(4-syrenesulfonic acid) (Mw 200,000) aqueous solution was made as in example 1-2.

[0078] Example 2 (Poly(4-styrenesulfonic acid)ammonium salt)

[0079] 10 g of 30% poly(4-syrenesulfonic acid)ammonium salt (Mw 200,000 aqueous solution) was diluted with 20 g of deionized water to form a 10% poly(4-styrenesulfonic acid)ammonium salt solution.

[0080] Example 3-1 (Polyvinylalcohol)

[0081] 4 g of polyvinylalcohol (40% hydrolyzed; Mw 9,000-10,000) was dissolved in 36 g of deionized water to form a 10% polyvinylalcohol solution.

[0082] Example 3-2 (Polyvinylalcohol)

[0083] 4 g of polyvinylalcohol (97-90% hydrolyzed; Mw 30,000-70-000) was dissolved in 36 g of deionized water to form a 10% polyvinylalcohol solution.

[0084] Example 3-3 (Polyvinylalcohol)

[0085] 4 g of polyvinylalcohol (87-89% hydrolyzed; Mw 1,800) was dissolved in 36 g of deionized water to form a 10% polyvinylalcohol solution.

[0086] Example 4 (Poly(acrylamide))

[0087] 4 g of poly(acrylamide) (Mw 40,000) was dissolved in 36 g of deionized water to form a 10% poly(acrylamide) solution.

[0088] Example 5 (Dextran)

[0089] 4 g of Dextran (Mw 9,000-11,000) was dissolved in 36 g of deionized water to form a 10% Dextran solution.

[0090] Example 6 (Poly(allylamine) solution)

[0091] 10 g of 20% poly(allylamine) solution (Mw 15,000) was diluted with 10 g ofDocket No. P23-168-WO-PCT deionized water to form a 10% poly(allylamine) solution.

[0092] Example 7 (Poly(methacrylic acid))

[0093] 10g of 10% sodium salt of poly(methacrylic acid) solution (Mw 9,500) and 8.18 g of deionized water were mixed and converted by way of ion exchange (Amberlyst™ A15) to yield a 5.5% poly(methacrylic acid) solution.

[0094] Example 8 (Poly(methyl vinyl ether-alt-maleic acid))

[0095] 4 g of poly(methyl vinyl ether-alt-maleic acid) (Mw 216,000) was dissolved in 36 g of deionized water to form a 10% poly(methyl vinyl ether-alt-maleic acid) solution.

[0096] Example 9 (Poly(vinylphosphoric acid))

[0097] 4 g of poly(vinylphosphoric acid) was dissolved in 36 g of deionized water to form a 10% poly(vinylphosphoric acid) solution.

[0098] Comparative Examples

[0099] The polymers used in the following Comparative Examples include repeat units from the Table 2 and as further described in each Comparative Example. OR O OR OROC OHOO RO O C NH O OR OR R= H or -EtOHCE1 CE2 CE3 CH2CHCO R O3CO R C x CO RyxCO RyR = H or Na R = H CE4 X~50, Y~50 CE5 CE6 OH O S O CE7 Table 2

[0100] Comparative Example 1 (Polyacrylic Acid)

[0101] 4 g of polyacrylic acid (Mw 1,800) was dissolved in 36 g of deionized water to form a 10% polyacrylic acid solution.

[0102] Comparative Example 2 (2-Hydroxyethyl Cellulose)

[0103] 4 g of 2-hydroxyethyl cellulose (Mw 90,000) was dissolved in 96 g of deionizedDocket No. P23-168-WO-PCT water to form a 4% 2-hydroxyethyl cellulose solution.

[0104] Comparative Example 3 (Poly(N-isopropylacrylamide), PNIPAM)

[0105] 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.

[0106] Comparative Example 4 (Poly(2-ethyl-2-oxazoline))

[0107] 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.

[0108] Comparative Example 5 (Poly(styrene-alt-maleic acid) Sodium Salt)

[0109] 10 g of 13% poly(styrene-alt-maleic acid) sodium salt (Mw 350,000) was diluted with 55g of deionized water to form a 2% poly(styrene-alt-maleic acid) sodium salt solution.

[0110] Comparative Example 6 (Poly(styrene-alt-maleic acid))

[0111] 30 g of 4.3% sodium salt of poly(styrene-alt-maleic acid) (Mw 350,000) aqueous solution was ion exchanged with Amberlyst™ A15 and to yield a 2.3% poly(styrene- alt-maleic acid) (Mw 350,000) aqueous solution was made as in example 1-2.

[0112] Comparative Example 7 (Poly(vinyl sulfonic acid), PVSA)

[0113] 10 g of 15% sodium salt of poly(vinyl sulfonic acid) (“PVSA”; Mw 15,000) aqueous solution and 9.2 g of deionized water were mixed and converted by way of ion exchange (Amberlyst™ A15) to yield a 7.8% of poly(vinyl sulfonic acid) solution.

[0114] Solubility Assessment

[0115] The formulations from Examples 1-9 and Comparative Examples 1-7 were spin coated on an 8-inch Si wafer and baked at 100 ^C for 60 sec with Tokyo Electron Act 8 Clean track (TEL Act 8). The film thickness was measured on cross section pictures by SEM. Each wafer was soaked with AZ ArF thinner or deionized water for 60 sec and spin dried. The results are summarized in Table 3. In Tables 3 and 4 the percent solubility (“% Sol.”) was calculated as percent function of initial thickness of the deposited edge bead and the thickness after exposure to ArF thinner which is commonly used as a casting solvent for resists, spin on hard mask etc. For example, in Example 1467 nm of the initial 480 nm edge bead remained (i.e., 97.3% of the initial thickness remained) after soaking in ArF thinner for 60 seconds which corresponds to 2.7% solubility. The percent solubility in water was calculated in the same manner.

[0116] In contrast, as shown in Table 3 and Table 4, formulations from Comparative Examples 1, 3, 4, 5, 6 and 7 dissolved in ArF thinner and cannot be used for protection material. The formulation from Comparative Example 2 was not soluble in ArF thinner but was not able to be readily removed with deionized water due to poor solubility. Thus, the formulation from Comparative Example 2 also cannot be used for protection material.Docket No. P23-168-WO-PCT Film Thickness (nm)Ex. Polymer MwSolid(%)Initial Soak% Soak % ArF T / 60sSol. DIW / 60s Sol.1-1Poly(4-styrene sulfonicacid) 75,000 10 480 467 2.7 16 96.71-2Poly(4-styrene sulfonicacid) 1,000,000 5 193 179 7.3 0 1001-3Poly(4-styrene sulfonicacid) 200,000 5 277 260 6.1 0 1002Poly(4-styrene sulfonicacid)ammonium salt 200,000 10 385 372 3.4 0 1003-1Polyvinylalcohol (40%9,000- hydrolyzed) 10,00010 552 505 8.5 17 96.93-2Polyvinylalcohol (97-30,000- 90% hydrolyzed) 70,00010 550 440 20 43 92.23-3Polyvinylalcohol (87-13,000- 89% hydrolyzed) 23,00010 549 542 1.3 28 94.94 Poly(acrylamide) 40,000 10 135 135 0 21 84.5 5Dextran 9,000-11,00010 204 204 0 0 1006Poly(allylamine)solution 15,000 10 564 564 0 0 1007 Poly(methacrylic acid) 9,500 5.5 130 125 3.8 0 100 8Poly(methyl vinylether-alt-maleic acid)216,000 10 312 266 14.7 0 1009Poly(vinylphosphoricacid) NA 10 194 191 1.5 0 100Table 3Docket No. P23-168-WO-PCT Film Thickness (nm) Ex. Polymer MwSolid(%)Initial Soak% Soak % ArF T / 60sSol. DIW / 60s Sol. Comp.1 Polyacrylic acid 1,800 10 185 17 90.8 13 93 Comp. 22-Hydroxyethylcellulose 90,000 3 120 110 8.3 90 25Poly(N- Comp.3 isopropylacrylaminde), 40,000 10 574 0 100 0 100 PNIPAM Comp. 4Poly(2-ethyl-2-oxazoline) 50,000 10 488 0 100 0 100Poly(styrene-alt- Comp.5 maleic acid) sodium 350,000 10 110 0 100 0 100 salt Comp. 6Poly(styrene-alt-maleic acid) 350,000 3 197.4 1.5 99.2 28.8 85.4Comp. 7Poly(vinyl sulfonicacid), PVSA NA 7.8 178 12 93.3 0 100Table 4

[0117] As can be seen from the above data, suitable water-soluble polymers are those that produce edge beads that (i) are greater than about 85% soluble in water and (ii) less than about 20% soluble in an organic-based EBR. Preferably, the water-soluble polymers are those that produce edge beads that (i) are greater than about 90% soluble in water and (ii) less than about 15% soluble in an organic-based EBR. More preferably, the water-soluble polymers are those that produce edge beads that (i) are greater than about 95% soluble in water and (ii) less than about 10% soluble in an organic-based EBR. Most preferably, the water-soluble polymers are those that produce edge beads that (i) are greater than about 95% soluble in water and (ii) less than about 5% soluble in an organic-based EBR.

[0118] Protection Test Against Metal Contamination

[0119] Formulations from Examples 1-3 were coated on an 8-inch Si wafer and baked at 100 ^C for 60 sec with TEL Act 8. On the deposited films a zirconium hard mask (EMD Electronics, AZ MHM1001J2N) was spin coated at 1500 rpm without baking. Each wafer was next soaked with AZ EBR7030 for 60 sec to remove the spin on Zr hardmask and then was spin dried. Thereafter, each wafer was soaked with deionized wafer for 60 sec, spin dried and soaked with deionized water for 60 sec, spin dried again. In Comparative Example 7, AZ MHM1001J2N was directly coated on the Si wafer but without any formulations of Examples 1-3.

[0120] Zr content on the Si wafer was measured with TXRF and is summarized in Table 5 and illustrated in FIG.3. As can be seen from Comparative Example 7 the residual Zr on theDocket No. P23-168-WO-PCT Si wafer for the directly coated hardmask is about 6900 x 1010atoms / cm2. In contrast, use of the disclosed and claimed EPL formulations produces a significant, multi-fold reduction in residual Zr on the Si wafers (i.e., about 130 to about 2300 x 1010atoms / cm2) resulting in the Si wafer being better protected from metal contamination. Ex. PolymerThicknessResidual (nm)Zr 1A Poly(4-styrene sulfonic acid) 1000 128 1-1 Poly(4-styrene sulfonic acid) 500 130 2 Poly(4-styrene sulfonic acid)ammonium salt 500 2285 3 Polyvinylalcohol (40% hydrolyzed) 500 1013 Comp.7 None 0 6904 Table 5

[0121] Although the disclosed and claimed subject matter has been described and illustrated with a certain degree of particularity, it is to be understood that the disclosure has been made only by way of example, and that numerous changes in the conditions and order of steps can be resorted to by those skilled in the art without departing from the spirit and scope of the disclosed and claimed subject matter.

Claims

Docket No. P23-168-WO-PCT Claims What is claimed is:

1. An edge protection layer (EPL) formulation comprising, consisting essentially of or consisting of (i) one or more water-soluble polymer and (ii) an aqueous solvent, wherein an EPL formed therefrom is (a) substantially or entirely insoluble in nonaqueous solvent and (b) soluble in water.

2. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 85% soluble in water and (ii) less than about 20% soluble in nonaqueous solvent.

3. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 90% soluble in water and (ii) less than about 15% soluble in nonaqueous solvent.

4. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 95% soluble in water and (ii) less than about 10% soluble in nonaqueous solvent.

5. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 95% soluble in water and (ii) less than about 5% soluble in nonaqueous solvent.

6. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 99% soluble in water and (ii) less than about 5% soluble in nonaqueous solvent.

7. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 99% soluble in water and (ii) less than about 1% soluble in nonaqueous solvent.

8. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 85% soluble in the aqueous solvent and (ii) less than about 20% soluble in nonaqueous solvent.

9. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 90% soluble in the aqueous solvent and (ii) less than about 15% soluble in nonaqueous solvent.

10. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 95% soluble in the aqueous solvent and (ii) less than about 10% soluble in nonaqueous solvent.

11. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 95% soluble in the aqueous solvent and (ii) less than about 5% soluble in nonaqueous solvent.

12. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 99% soluble in the aqueous solvent and (ii) less than about 5% soluble in nonaqueous solvent.

13. The EPL formulation of claim 1, wherein the formed EPL is (i) greater than about 99% soluble in the aqueous solvent and (ii) less than about 1% soluble in nonaqueous solvent.

14. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises one or more polymers having at least 90% of one or more repeat units from Table 1 not including end groups:Docket No. P23-168-WO-PCT OH O S O O S O OH ONH(iii) (i) (ii) O O NH C NH O22HO OH CH3OH (iv) (v) (vi) O CO2H O C OH HO P OH CH3OCH3CO2H(vii) (viii) (ix)15. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises one or more polymers having at least 95% of one or more repeat units from Table 1 not including end groups.

16. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises one or more polymers having at least 98% of one or more repeat units from Table 1 not including end groups.

17. The EPL formulation of claim 1, wherein the one or more water-soluble polymer consists essentially of one or more repeat units from Table 1 not including end groups.

18. The EPL formulation of claim 1, wherein the one or more water-soluble polymer consists of one or more repeat units from Table 1 not including end groups.

19. The EPL formulation of claim 1, wherein the one or more water-soluble polymer consists essentially of one repeat unit from Table 1 not including end groups.

20. The EPL formulation of claim 1, wherein the one or more water-soluble polymer consists of one unit from Table 1 not including end groups.

21. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises one or more of poly(4-stylenesulfonic acid), poly(4-styrene sulfonic acid)ammonium salt, polyvinylalcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether-Docket No. P23-168-WO-PCT alt-maleic acid) and poly(vinylphosphoric acid).

22. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises two or more of poly(4-stylenesulfonic acid), poly(4-styrene sulfonic acid)ammonium salt, polyvinylalcohol (about 40% to about 97% hydrolyzed), poly(acrylamide), dextran, poly(allylamine), poly(methacrylic acid), poly(methyl vinyl ether- alt-maleic acid) and poly(vinylphosphoric acid).

23. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises poly(4-stylenesulfonic acid).

24. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises poly(4-styrene sulfonic acid)ammonium salt.

25. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises polyvinylalcohol (about 40% to about 97% hydrolyzed).

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

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

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

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

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

31. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises poly(vinylphosphoric acid).

32. The EPL formulation of claim 1, wherein the aqueous solvent consists essentially of water.

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

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

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

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

37. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 85 wt% of water.Docket No. P23-168-WO-PCT 38. The EPL formulation of claim 1, wherein the aqueous solvent comprises at least about 90 wt% of water.

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

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

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

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

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

44. The EPL formulation of claim 1, wherein the one or more water-soluble polymer comprises at least one water-miscible organic solvent selected from the group of an alcohol, an ether and a ketone.

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

46. A semiconductor manufacturing process comprising the steps of: (a) applying one or more of the EPL formulations of any of claims 1-45 on an edge and at least one proximate surface of a wafer or substrate; (b) heating the applied one or more of the EPL formulations to form an edge protection layer on the edge and at least one proximate surface of the wafer or substrate; (c) applying a metal containing composition to the wafer or substrate and the edge protection layer; (d) removing at least a portion of the applied metal containing composition that is in contact with the edge protection layer; (e) heating the applied metal containing composition to form the metal based functional film; (f) removing the edge protection layer with an aqueous remover solvent; and (g) optionally performing at least one post applied bake.

47. The method of claim 46, wherein the aqueous remove solvent includes, consist essentially of or consist of water.

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

Images