HK1066554B - Polycyclic fluorine-containing polymers and photoresists for microlithography - Google Patents

Description

Polycyclic fluoropolymers and photoresists for microlithography

RELATED APPLICATIONS

The entire contents of provisional application 60/280,269 are incorporated herein by reference.

Background

1. Field of the invention

The present invention relates to photoimaging and in particular to the use of photoresists (positive and/or negative) for imaging in the manufacture of semiconductor devices. The present invention also relates to novel fluoropolymer compositions useful as matrix resins in photoresists and many other potential applications.

2. Description of the related Art

Polymeric products are used as components of imaging and photosensitive systems, and particularly photoimaging systems, as described in microlithography guidance, 2 nd edition, l.f. thompson, c.g. willson, and m.j. bowden, american society of chemists, Washington, DC, 1994. In such systems, Ultraviolet (UV) light or other electromagnetic radiation strikes a material containing a photoactive component causing a physical or chemical change in the material. Thereby producing a useful or latent image that can be developed into a useful image for semiconductor device fabrication.

While the polymer product itself may be photoactive, typically the photosensitive composition includes one or more photoactive components in addition to the polymer product. Upon exposure to electromagnetic radiation (e.g., UV light), the photoactive component functions to alter the rheological state, solubility, surface properties, refractive index, color, electromagnetic properties, or other such physical or chemical properties of the photosensitive composition, as described in the Thompson et al publication.

To reflect very fine features at the sub-micron level in semiconductor devices, electromagnetic radiation in the far or extreme Ultraviolet (UV) region is required. Semiconductor fabrication is typically performed using positive photoresists. Lithography using novolak polymers and diazonaphthoquinones as dissolution inhibitors in the 365nm (1-line) UV region is currently the established chip technology with resolution limits of about 0.35-0.30 microns. Lithography using p-hydroxystyrene polymers in the 248nm far UV region is known and has a resolution limit of 0.35-0.18 microns. Because the lower resolution limit is further reduced as the wavelength is shortened (i.e., resolution limit of 0.18-0.12 microns for 193nm imaging), there is a strong driving force for future photolithography at shorter wavelengths. Photolithography using 193nm exposure wavelength (obtained from an argon-fluorine (ArF) excimer laser) is the leading candidate for future microelectronics manufacturing using 0.18 and 0.13 μm design rules. Using an exposure wavelength of 157nm (using F)₂Laser source derived) may be used in future microelectronic manufacturing using design rules of 0.100 μm or less. The opacity of conventional near-UV and far-UV organic photoresists at 193nm and shorter wavelengths precludes their application possibilities in single layer schemes at these wavelengths.

Some resist compositions suitable for imaging at 193nm are known. For example, photoresist compositions comprising cyclic olefin maleic anhydride alternating copolymers have been shown to be useful for imaging semiconductors at 193nm (see F.M. Houliuhan et al, Macromolecules, 30, pp 6517-6534 (1997); T.Wallow et al, SPIE, Vol.2724, pp 355-364; and F.M. Houliuhan et al, Journal of Photoenzymer Science and technology, 10, No.3, pp 511-520 (1997)). Several publications are concerned with resists at 193nm (i.e., U.Okoroanyanwu et al, SPIE, Vol.3049, pages 92-103; R.Allen et al, SPIE, Vol.2724, pages 334-. Compositions comprising functionalized norbornene addition polymers and/or ROMP (ring opening metathesis polymerization) polymers thereof have been disclosed (e.g. PCT WO 97/33198(9/12/97) by b.f. goodrich). Homopolymers of norbornadiene and maleic anhydride copolymers thereof and their use in 193nm lithography have been disclosed (J.Niu and J.Frechet, Angew. chem. int. Ed., 37, No.5, (1998), 667-670).

Copolymers of fluoroolefin monomers and certain cyclic unsaturated monomers are described in U.S. Pat. Nos. 5,177,166 and 5,229,473, but they do not disclose the use of these copolymers in any photosensitive composition.

Homopolymers and copolymers of certain monomers which are both cyclic and fluorine-containing and their use as components in fluorine-containing polymer films for the optical field are disclosed in Japanese patent laid-open publication No. Hei 9(1997) -43856. There is no mention in this document of homopolymers or copolymers comprising polycyclic comonomers as photoresist components. Further, there is no mention that the composition disclosed in this Japanese patent laid-open publication can be used for a resist for image formation in an extreme ultraviolet region having a wavelength of less than 180 nm.

U.S. patent 5,655,627 discloses a method for producing negative tone resist images by coating silicon wafers with a copolymer resist solution of pentafluoropropyl methacrylate-t-butyl methacrylate in a solvent, followed by exposure at 193nm and development with a carbon dioxide critical fluid.

There is a need for photoresist compositions useful at 193nm or shorter wavelengths, particularly 157nm, that have not only high transparency at these short wavelengths but also other desirable key properties, including good plasma etch resistance and adhesion.

Summary of The Invention

The present invention relates to a fluoropolymer comprising repeating units derived from at least one ethylenically unsaturated polycyclic compound of structure 1:

wherein:

R¹-R⁸are identical or different and each represents a hydrogen atom, a halogen atom, a carboxyl group, a hydrocarbon group containing 1 to 20 carbon atoms or a substituted hydrocarbon group containing 1 to 20 carbon atoms and at least one oxygen, sulfur or nitrogen atom; and is

m is 0, 1 or 2.

In another embodiment, the present invention relates to a polymer comprising the polymerization product of bicyclo- [2.2.1] -1, 5-heptadiene and a fluoroolefin, preferably tetrafluoroethylene and chlorotrifluoroethylene.

In another embodiment, the invention relates to a photoresist composition comprising the fluoropolymer of structure 1 and a photoactive component.

In another embodiment, the present invention relates to a method of making a photoresist image on a substrate by using the photoresist composition of the present invention.

In another embodiment, the invention relates to an article having a photoresist composition coated on a substrate.

Detailed description of the preferred embodiments

Fluorine-containing polymer

The fluoropolymer comprises repeating units derived from at least one ethylenically unsaturated polycyclic compound of structure 1:

wherein:

R¹-R⁸are the same or different and each represents a hydrogen atom, a halogen atom, a carboxyl group, a hydrocarbon group having 1 to 20 carbon atomsOr a heteroatom-substituted hydrocarbon group containing 1-20 carbon atoms and one or more heteroatoms. The value of m is 0, 1 or 2. The hydrocarbon group may be linear or branched, paraffinic or olefinic, alicyclic or aromatic. Suitable heteroatoms include oxygen, nitrogen or sulfur. Examples of hydrocarbon groups containing oxygen as a heteroatom are alkyl carboxylate groups containing 1 to about 20 carbon atoms, preferably 3 to about 14 carbon atoms, or alkoxy groups containing 1 to about 20 carbon atoms. When the hydrocarbon group is an alkyl carboxylate group, it can be a secondary or tertiary alkyl carboxylate group, which is preferred because such alkyl carboxylates are more susceptible to cleavage than primary alkyl carboxylate groups. It is useful to limit the content of aromatic substituents for transparency at shorter wavelengths. Generally, the polymer is free of aromatic groups.

A representative preferred ethylenically unsaturated polycyclic compound is 3, 3, 4, 4-tetrafluorotricyclo [4.2.1.02, 5] -7-nonene (NB-TEF) having the formula

The ethylenically unsaturated polycyclic compounds of structure 1 can be prepared by methods known in the art. In one method, norbornadiene or a suitably selected derivative is reacted with a fluoroolefin, as disclosed by Brasen (U.S. Pat. No. 2,928,865(1960)) and as shown in equation 1 (below). In another method, cyclopentadiene or a suitably selected derivative may be reacted with 3, 3, 4, 4-tetrafluorocyclobutene, as disclosed by Shozda and Putnam (Journal of Organic Chemistry, Vol27, p.1557-1561 (1962)) and as shown in equation 2 (see below).

Equation 1

Equation 2

The presence of at least one polycyclic comonomer (i.e., a comonomer containing at least two rings, such as norbornene) in the compound of structure 1 is important for three main reasons: 1) polycyclic monomers have a relatively high carbon to hydrogen ratio (C: H), and the resulting matrix polymer, which contains repeat units of these polycyclic monomers, generally has good plasma etch resistance; 2) polymers containing repeat units derived from polycyclic monomers (preferably fully saturated upon polymerization) generally have good transparency characteristics; 3) polymers prepared from polycyclic monomers generally have higher glass transition temperatures, which can improve dimensional stability during processing. Polymers containing repeat units derived from polycyclic comonomers having high C: H ratios have lower Ohnishi values (O.N.), where:

O.N.＝N/(N_C-N_O)

n is the number of atoms in the repeating unit of the polymer, N_CIs the number of carbon atoms in the repeating unit of the polymer, and N_OIs the number of oxygen atoms in the polymer repeat unit. One empirical rule found by Ohnishi et al (j.electrochem. soc., Solid-State sci.technol., 130, 143(1983)) reveals that the Reactive Ion Etching (RIE) rate of a polymer is linear with the Ohnishi value (O.N.). For example, polynorbornene has the formula (C)₇H₁₀)_nAnd o.n. 17/7 2.42. Polymers comprising predominantly carbon and hydrogen containing polycyclic moieties with fewer oxygen containing functional groups will have lower o.n. values and correspondingly lower (in a substantially linear fashion) RIE rates according to the Ohnishi rule of thumb.

A suitable polycyclic compound that may be used to form the compound of structure 1 is bicyclo- [2.2.1] -2, 5-heptadiene, such as the species described in U.S. Pat. No. 2,928,865, which is incorporated herein by reference. Preferred cyclic compounds which may be used are bicyclo- [2.2.1] -2, 5-heptadiene having the following structure:

wherein R is¹²And R¹³Is hydrogen, an alkyl group containing not more than 6 carbon atoms or a carboxyl group or a group which can be hydrolyzed thereto. Hydrolyzable R¹And R²Examples of radicals are cyano, ethoxycarbonyl and dimethylcarbamoyl.

Suitable fluoroolefins that may be used to form the compounds of structure 1 are described in U.S. patent 2,928,865, which is incorporated herein by reference.

For example, more generally, fluoroolefins containing at least one ethylenically unsaturated compound containing at least one fluorine atom covalently attached to an ethylenically unsaturated carbon atom may be used. The fluoroolefin may contain from 2 to about 20 carbon atoms and preferably the site of unsaturation of the olefin is in a terminal position. In one embodiment, the terminal carbon group of the olefinic bond is attached to at least one fluorine atom and the remaining carbon atoms of the olefinic bond are attached to a hydrogen atom, fluorine, chlorine or bromine atom, or an omega-hydroperfluoroalkyl group of no more than about 10 carbon atoms, or a perfluoroalkyl group of no more than about 10 carbon atoms, on the one hand, and a hydrogen atom, fluorine, chlorine or bromine atom, an alkyl group, an omega-hydroperfluoroalkyl group, a perfluoroalkyl group, or a haloalkyl group containing at least one fluorine, chlorine or bromine atom and an alkyl group, a fluoroalkyl group or a haloalkyl group containing from 1 to about 10 carbon atoms, on the other hand, by a single bond.

More specifically, the fluoroolefin may have the following structure:

wherein A is a fluorine, chlorine or bromine atom, or an omega-hydroperfluoroalkyl group containing from 1 to about 10 carbon atoms, or a perfluoroalkyl group containing from 1 to about 10 carbon atoms or a perfluoroalkoxy group containing from 1 to about 10 carbon atoms; r 'and R' are each the same or different A, hydrogen, an alkyl group containing from 1 to about 10 carbon atoms, or a haloalkyl group containing at least one fluorine, chlorine or bromine atom and from 1 to 10 carbon atoms or R 'and R' together form a ring structure.

Specific examples of fluoroolefins include, but are not limited to, tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, vinylidene fluoride, vinyl fluoride, perfluoro- (2, 2-dimethyl-1, 3-dioxole), perfluoro- (2-methylene-4-methyl-1, 3-dioxolane), CF₂＝O(CF₂)_tCF＝CF₂Wherein t is 1 or 2, and R_fOCF₂＝CF₂Wherein R is_fIs a saturated fluoroalkyl group containing from 1 to about 10 carbon atoms. The preferred fluoroolefin is tetrafluoroethylene.

It has been found that the compounds of structure 1 form polymers by a polymerization process. As is well known to those skilled in the polymer art, free radical polymerization of ethylenically unsaturated compounds results in polymers having repeating units derived from the ethylenically unsaturated compound. Free radical polymerization processes can be used to prepare polymers derived from structure 1, which can optionally include at least one other monomer known to undergo free radical polymerization. Thus, for example, free radical polymerization can be used to prepare a polymer comprising structure 1 and another repeat unit derived from at least one ethylenically unsaturated compound containing at least one fluorine atom covalently bonded to an ethylenically unsaturated carbon atom. Fluorocopolymers containing only repeat units derived from a full-ring comonomer and completely no repeat units derived from a comonomer containing one or more fluorine atoms attached to an ethylenically unsaturated carbon atom can be prepared by vinyl-addition polymerization and ring-opening metathesis polymerization (ROMP). Vinyl-addition polymerization processes using nickel and palladium catalysts are disclosed in the following documents: 1) okoroanyanwu u.; shimokawa, t.; byers, j.d.; willson, c.g.j.mol.catal.a: chemical 1998, 133, 93; 2) PCT WO 97/33198(9/12/97) assigned to b.f. goodrich; 3) reinmuth, a.; mathew, j.p.; melia, j.; risse, w.macromol.rapid commu.1996, 17, 173; and 4) Breunig, S.; risse, w.macromol.chem.1992, 193, 2915. Ring-opening metathesis polymerization methods are disclosed in the above-mentioned documents 1) and 2), using ruthenium and iridium catalysts; and 5) Schwab, P.; grubbs, r.h.; ziller, j.w.j.am.chem.soc.1996, 118, 100; and 6) Schwab, P.; france, m.b.; ziller, j.w.; grubbs, r.h.angelw.chem.int.ed.engl.1995, 34, 2039.

Preferably, the polymerization reaction is carried out to form macromolecules having more than two repeating units. Preferably the molecular weight (Mn) of the polymer of the invention is greater than 2,000, preferably greater than 4,000.

The polymer derived from the compound of structure 1 may further comprise a repeat unit derived from a fluoroolefin. Suitable fluoroolefins include those described above for the preparation of compounds of structure 1. When the fluoroolefin is tetrafluoroethylene, the resulting polymer can have a high glass transition temperature and low absorption at 157nm when used in a photoresist composition.

The polymer of the present invention may further comprise a fluoroalcohol group. The fluoroalcohol group may be derived from at least one ethylenically unsaturated compound containing a fluoroalcohol group having the structure:

-C(R_f)(R_f’)OH

wherein R is_fAnd R_f' are identical or different fluoroalkyl groups having from 1 to about 10 carbon atoms or are composed together (CF)₂)_nWherein n is 2 to 10. These fluoroalkyl groups are designated R_fAnd R_f', which may be partially fluorinated alkyl groups or fully fluorinated alkyl groups (i.e., perfluoroalkyl groups). Broadly, R_fAnd R_f' are identical or different fluoroalkyl groups having from 1 to about 10 carbon atoms or are composed together (CF)₂)_nWherein n is 2 to 10. In the last sentence, the term "co-construction" indicates R_fAnd R_f' rather than separate, individual fluorinated alkyl groups, they may be joined to form a ring structure, as shown in the 5-membered ring case below:

according to the inventionMing R_fAnd R_f' may be, without limitation, a partially fluorinated alkyl group, but must be present in a sufficient degree of fluorination to render the hydroxyl (-OH) groups of the fluoroalcohol functional group acidic so that hydroxyl protons are substantially removed in a basic medium, such as aqueous sodium hydroxide or aqueous tetraalkylammonium hydroxide. In a preferred aspect of the invention, sufficient fluoro substituents will be present in the fluorinated alkyl group of the fluoroalcohol functional group such that the hydroxyl group has the following pKa value: pKa is more than 5 and less than 11. Preferably R_fAnd R_f' independently is a perfluoroalkyl group containing 1-5 carbon atoms and most preferably R_fAnd R_f' both are trifluoromethyl (CF)₃)。

When the fluoropolymer of the present invention comprises a fluoroalcohol, the fluoroalcohol group may have the following structure:

-XCH₂C(R_f)(R_f’)OH

wherein R is_fAnd R_f' As mentioned above, X is an element of groups VA and VIA of the periodic Table of the elements (CAS version), such as oxygen, sulfur, nitrogen and phosphorus. Oxygen is a preferred X group.

Illustrative, non-limiting examples of some representative comonomers containing a fluoroalcohol functional group and falling within the scope of the present invention are listed below:

CH₂＝CHOCH₂CH₂OCH₂C(CF₃)₂OH CH₂＝CHO(CH₂)₄OCH₂C(CF₃)₂OH

the polymer may further comprise at least one acid-containing monomer of the following structural units:

wherein E₁Is H or C₁-C₁₂An alkyl group; e₂Is CO₂E₃，SO₃E or other acidic groups; and E₃Is H or C₁-C₁₂Alkyl, the latter being unsubstituted or heteroatom-substituted. Suitable heteroatoms are oxygen, nitrogen, sulfur, halogen or phosphorus atoms. When the heteroatom is oxygen, the substituent may comprise a hydroxyl group. The alkyl group may contain from 1 to about 12, and preferably from 1 to about 8 carbon atoms. Preferably, the acidic group is a carboxylic acid. Preferred other monomers are acrylates. Tert-alkyl acrylates such as t-butyl acrylate and 2-methyl-2-adamantyl acrylate can provide the acid sensitive functionality necessary for imaging as discussed above. Other acrylates, such as acrylic acid and methyl acrylate, may be used to improve the adhesion or solubility of the polymer. In one embodiment, t-butyl acrylate may be incorporated into the polymer, which incorporates an acid sensitive t-butyl ester group. The level of carboxylic acid groups available in the polymer for a given composition depends on the amount optimized for good development in aqueous alkaline developer.

Additional polar monomers such as vinyl acetate may also be incorporated into the polymer to aid in aqueous development or to otherwise improve polymer properties.

The fluoroalcohol group and/or other acidic group of the polymer may contain a protecting group which protects the fluoroalcohol group and/or other acidic group (i.e., the protected group) from exhibiting its acidity in this protected state. As an illustrative example, a tert-butyl group is a protecting group in a tert-butyl ester and this protecting group can protect the free acid. Upon deprotection (conversion of the protected acid to the free acid), the ester is converted to the corresponding acid.

The α -alkoxyalkyl ether group is a preferred protecting group for the fluoroalcohol group to maintain a high level of transparency of the photoresist composition. The resulting protected fluoroalcohol group has the following structure:

C(R_f)(R_f’)O-CH₂OCH₂R_x

in this protected fluoroalcohol, R_fAnd R_f' as described above; r_xIs hydrogen or a linear or branched alkyl group containing 1 to 10 carbon atoms. An illustrative, but non-limiting example of an alpha-alkoxyalkyl ether group as an effective protecting group in a protected acid group is methoxymethyl ether (MOM). Protected fluoroalcohols bearing this particular protecting group may be obtained by reacting chloromethyl methyl ether with a fluoroalcohol.

Any of the other monomers described above may be used in the polymers of the present invention. For example, the fluoroalcohol functional groups described herein (protected or deprotected) may be used alone or in combination with one or more other acidic groups, such as carboxylic acid functional groups (deprotected) or carboxylic acid tert-butyl ester functional groups (protected).

In the present invention, the component containing a protected group is often, but not always, a repeating unit having a protected acidic group incorporated into the matrix polymer resin of the composition.

The protected acidic groups are typically present in one or more comonomers that can be polymerized to form the polymers of the present invention. Alternatively, in the present invention, the polymer may be formed by: polymerization with acid-containing comonomers and partial or complete conversion of the acidic functions in the resulting acid-containing polymers to derivatives with protected acidic groups can then be carried out by suitable methods.

Photoresist development

The fluoropolymers of the present invention have been found to be useful in photoresist compositions.

The photoresist compositions of the present invention include at least one photoactive component (PAC) that can generate an acid or a base when exposed to actinic radiation during the development process. PAC is called a photoacid generator (PAG) if exposed to actinic radiation to generate an acid. PAC is called photobase generator (PBG) if exposed to actinic radiation to generate a base.

Suitable photoacid generators for the present invention include, but are not limited to, 1) sulfonium salts (structure I), 2) iodonium salts (structure II), and 3) hydroxamates, such as structure III.

In structures II-IV, R₉-R₁₁Independently is substituted or unsubstituted C₆-C₂₀Aryl or substituted or unsubstituted C₇-C₄₀An alkylaryl or arylalkyl group. Representative aryl groups include, but are not limited to, phenyl, naphthyl, anthracene, and iodonium. Suitable heteroatom substituents include, but are not limited to, one or more oxygen, nitrogen, halogen or sulfur atoms. When the heteroatom is oxygen, the substituent may comprise hydroxyl (-OH) and C₁-C₂₀Alkoxy (e.g. C)₁₀H₂₁O). In structures III-IV the anion X-can be, but is not limited to SbF₆ ^-(hexafluoroantimonate), CF₃SO₃ ^-(triflate ═ triflate) and C₄F₉SO₃ ^-(perfluorobutanesulfonate).

Iodonium photoacid generators of particular utility have the following structure:

developing functional group

For use in a photoresist composition, the fluoropolymer should contain sufficient functional groups to develop the photoresist to produce a relief image, which is then exposed to UV radiation having a wavelength of 365 nm. In some preferred embodiments, a sufficient amount of functional groups are selected from the acids and/or protected acidic groups described above. It has been found that these acids or protected acidic groups cause the exposed portions of the photoresist to dissolve in alkaline solution and the unexposed portions to be insoluble in alkaline solution upon exposure to sufficient ultraviolet radiation having a wavelength of 365 nm.

For development, one or more of the groups in the fluoropolymer should contain one or more components containing protected acidic groups that are rendered hydrophilic by the catalytic action of an acid or base generated by photolysis of a photoactive compound (PAC).

The particular protected acidic group is typically selected based on such considerations as: it is acid labile, so when the image exposure produces photoacid, the acid will catalyze the deprotection process and the hydrophilic acid groups necessary for development under aqueous conditions. In addition, the fluoropolymer may also contain unprotected acid functional groups.

Examples of alkaline developers include, but are not limited to, sodium hydroxide solution, potassium hydroxide solution, or ammonium hydroxide solution. Specifically, the alkaline developer is an aqueous alkaline liquid, such as an aqueous solution containing 0.262N tetramethylammonium hydroxide (typically 120 seconds or less at 25 ℃ development) or 1 wt% sodium carbonate (typically 2 minutes or less at 30 ℃ development).

When an aqueous processable photoresist is coated or otherwise applied to a substrate and exposed to a uv image, development of the photoresist composition requires that the binder should contain sufficient acidic groups (e.g., carboxylic acid groups) and/or protected acidic groups that are at least partially deprotected upon exposure to render the photoresist (or other photoimageable coating composition) processable in an aqueous alkaline developer.

In one embodiment of the invention, the polymer contains one or more protected groups, and the polymer converts carboxylic acids, which are hydrophilic groups, to photoacid upon exposure. Such protected acidic groups include, but are not limited to, A) esters capable of forming or rearranging to a tertiary cation, B) lactone esters, C) acetal esters, D) β -cyclic ketoesters, E) α -cyclic ether esters, and F) MEEMA (methoxyethoxyethyl methacrylate) and other esters that are susceptible to hydrolysis due to ortho-assist. Some specific examples of class A are tert-butyl esters, 2-methyl-2-adamantyl esters, and isobornyl esters. Some specific examples of species B are 3-gamma-butyrolactone, 2-gamma-butyrolactone, mavalonic lactone, 3-methyl-3-gamma-butyrolactone, 3-tetrahydrofuranyl, and 3-oxocyclohexyl. Some specific examples of class C are 2-tetrahydropyranyl, 2-tetrahydrofuranyl, and 2, 3-propylene-1-carbonate. Other examples of class C include various esters from vinyl ether addition, such as ethoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, and acetoxyethoxyethyl vinyl ether.

A particularly preferred acidic group is a hexafluoroisopropanol group that can be introduced by using a hexafluoroisopropanol-containing monomer. Some or all of the hexafluoroisopropanol groups may be protected, for example, as acid labile alkoxymethyl ethers or tert-butyl carbonates.

Examples of components containing protected acid groups that produce alcohols as hydrophilic groups upon exposure to photogenerated acids or bases include, but are not limited to, t-butoxycarbonyl (t-BOC), t-butyl ether, and 3-cyclohexenyl ether.

In the case of a negative photoresist layer, the portions of the photoresist layer not exposed to ultraviolet radiation are removed during development using a critical fluid or organic solvent, while the exposed portions are substantially unaffected during development.

Dissolution inhibitors and additives

Various dissolution inhibitors may be used in the photoresist composition of the present invention. Ideally, Dissolution Inhibitors (DIs) for extreme and extreme ultraviolet resists (e.g., 193nm resists) should be designed/selected to meet a variety of material requirements: including dissolution inhibition, plasma etch resistance, and the adhesion behavior of a resist composition containing a given DI additive. Some dissolution inhibiting compounds may also be used as plasticizers in the resist composition.

Many bile salt esters (i.e., cholate esters) are particularly useful as DIs in the compositions of the present invention. Bile salt esters are known to be effective dissolution inhibitors for deep ultraviolet photoresists, a work which has been initiated by Reichmanis et al in 1983 (E.Reichmanis et al, "influence of substituents on photosensitivity of 2-nitrobenzyl ester deep ultraviolet photoresists", J.electrochem. Soc.1983, 130, 1433-1437.) bile salt esters have been selected as a particularly attractive DIs for several reasons including their ready availability from natural sources, their high alicyclic carbon content, and in particular their transparency in the deep and vacuum ultraviolet regions of the electromagnetic spectrum (i.e., the far and extreme ultraviolet regions in nature) (e.g., they are highly transparent at 193 nm). In addition, bile salts esters are also attractive DI alternatives because they can be designed to have a wide range of hydrophobic and hydrophilic compatibility depending on the degree of hydroxyl substitution and functionalization.

Representative bile acids and bile acid derivatives suitable for use as additives and/or dissolution inhibitors in accordance with the present invention include, but are not limited to, those described below: cholic acid (IV), deoxycholic acid (V), lithocholic acid (VI), deoxycholic acid tert-butyl ester (VII), lithocholic acid tert-butyl ester (VIII), and 3-alpha-acetyllithocholic acid tert-butyl ester (IX). Bile acid esters comprising compounds VII-IX are preferred dissolution inhibitors of the present invention.

Cholic acid deoxycholic acid lithocholic acid

IV V VI

Deoxycholic acid tert-butyl ester lithocholic acid tert-butyl ester 3-alpha-acetyllithocholic acid tert-butyl ester

VII VIII IX

The present invention is not limited to the use of bile acid esters and related compounds as dissolution inhibitors. Other types of dissolution inhibitors, such as various Diazonaphthoquinones (DNQs) and Diazocoumarins (DCs), may be used in certain applications of the present invention. Diazonaphthoquinones and diazocoumarins are generally suitable for use in resist compositions designed for imaging with higher wavelength ultraviolet light (e.g., 365nm and perhaps 248 nm). These dissolution inhibitors are generally not preferred in resist compositions designed for 193nm or lower wavelength ultraviolet light imaging because these compounds absorb strongly in the ultraviolet region and are generally not sufficiently transparent for most applications in these low ultraviolet wavelength regions.

Solvent:

the photoresists of the invention may be formulated with solvents such as chlorobenzene, methyl ethyl ketone, cyclohexanone or propylene glycol methyl ether acetate. The solvent may be chlorobenzene and methyl ethyl ketone or propylene glycol methyl ether acetate and cyclohexanone.

Other Components

The photoresist composition of the present invention may include optional other components. Examples of other components that may be added include, but are not limited to, bases, surfactants, resolution enhancers, tackifiers, residual thinning liquids (residues), coating aids, plasticizers, and Tg (glass transition temperature) modifiers.

Processing step

For microlithography, the photoresist compositions of the present invention are applied to suitable substrates such as microelectronic wafers commonly used in the semiconductor industry. Examples include, but are not limited to, silicon wafers. The solvent is subsequently dried.

Imagewise exposure

The photoresist compositions of the invention are sensitive in the ultraviolet region of the electromagnetic spectrum and in particular in the wavelength region of less than or equal to 365 nm. Imagewise exposure of the photoresist compositions of the present invention can be carried out in a number of different ultraviolet wavelength regions, including, but not limited to 365nm, 248nm, 193nm, 157nm and lower. The image exposure is preferably carried out in the ultraviolet region at a wavelength of 248nm, 193nm, 157nm or less; more preferably at 193nm, 157nm or lower; and more preferably in the ultraviolet region of 157nm or less. The image exposure may be digitally exposed using a laser or equivalent device or non-digitally exposed using a photomask. Digital imaging using a laser is preferred. Suitable laser devices for digital imaging of the compositions of the present invention include, but are not limited to, argon-fluorine excimer lasers for ultraviolet output at 193nm, krypton-fluorine excimer lasers for ultraviolet output at 248nm, and fluorine (F2) lasers for output at 157 nm. As described above, the use of lower wavelengths (e.g., 193nm or 157nm or lower) is preferred over the use of higher wavelengths (e.g., 248nm or higher) because image exposure using lower wavelength ultraviolet light corresponds to higher resolution (lower resolution limit). In particular, imaging at 157nm is more preferable than imaging at 193nm for this reason.

The photoresists of the invention can be used for 365nm (1-line), 248nm (KrF laser), especially 193nm (ArF laser) and 157nm (F2 laser) microlithography. These photoresists are critical for use in feature size imaging in the sub-01.0 micron range.

Glossary

Compound/monomer

CFC-1131, 1, 2-trichlorotrifluoroethane

DMF dimethyl formamide

TFE tetrafluoroethylene (E.I.du Pont de Nemours and

Company，Wilmington，DE)

NB norbornene ═ bicyclo [2.2.1] -2-heptene

Aldrich Chemical Co.，Milwaukee，WI

NB-TFE 3, 3, 4, 4-tetrafluoro-tricyclo [4.2.1.0^2，5]-7-nonene, which is a non-aromatic hydrocarbon,

CAS#3802-76-4

THF tetrahydrofuran

Aldrich Chemical Co.，Milwaukee，WI

Perkadox^*16N bis (4-tert-butylcyclohexyl) percarbonate (peroxodi)

carbonate)

Noury Chemical Corp.，Burt，NY

HFIBO hexafluoroisobutylene peroxide

TBA Tert-butyl acrylate

General of

Ultra-far UV 10nm-200nm ultraviolet electromagnetic spectrum region

Ultraviolet electromagnetic spectrum region of far UV 200nm-300nm

UV 10nm-390nm in the ultraviolet electromagnetic spectrum

Near UV 300nm-390nm ultraviolet electromagnetic spectrum region

M_nNumber average molecular weight of a given polymer

M_wWeight average molecular weight of a given polymer

P＝M_w/M_nPolydispersity of a given polymer

Absorption coefficient AC ═ a/b, where a is absorbance, ═ Log₁₀(1/T) and b ═ film

In micrometers, wherein T ═ light transmission defined below

And (4) rate.

Transmittance, T ═ the radiant power transmitted through the sample and the incident light on the sample

Upper radiation power ratio and is determined at a specific wavelength mu

Tg glass transition temperature

Examples

All temperatures are degrees celsius, all mass measurements are in grams, and all percentages are weight percentages, but the polymer composition is in mole percentages.

The glass transition temperature (Tgs) was measured by DSC (differential scanning calorimetry) at a heating rate of 20 ℃/min, and data for the second heating was recorded. The DSC apparatus used was a DSC2910 instrument manufactured by taiinstruments, Wilmington, DE.

Examples

Comparative example 1A: TFE/norbornene Polymer:

a solution of 33g (0.35mol) of norbornene dissolved in 120mL of CFC-113 was charged into a 400mL stainless steel pressure vessel. Adding Perkadox^*16N (1.20 g). The vessel was closed, purged with nitrogen, cooled, evacuated and charged with 40g (0.40mol) TFE. The vessel was heated to 50 ℃ and held for 18hr with shaking, and the internal pressure was reduced from 200psi to 167 psi. The vessel was cooled, vented and rinsed with additional CFC-113 recovered liquid feed. The polymer was separated into excess methanol by precipitation of the CFC-113 solution. The white solid was filtered and dried in a vacuum oven at about 65 ℃ overnight. 29.7g (41%) of a white polymer are isolated; GPC (MEK) Mw 10000, Mn 2900, Mw/Mn 3.57. And (4) analyzing to obtain: c, 54.60; h, 5.05; f, 31.21. Calculated as C%, the polymer composition contained 52 mol% TFE and 48 mol% norbornene.

Comparative example 1B: TFE/norbornene copolymer:

another sample of TFE/norbornene copolymer prepared by the procedure of comparative example 1A, using 47g (0.5mol) norbornene, 120mL CFC-113, 1.6g Perkadox^*16N and 50g (0.50mol) TFE, polymerization was carried out at 40 ℃ for 18 hr. 19.7g (20%) of a white polymer are isolated; GPC (MEK) Mw 10600, Mn 3700, Mw/Mn2.89 intrinsic viscosity 0.0195 (MEK). And (4) analyzing to obtain: c, 58.33; h, 5.63; f, 33.13. Calculated as C%, the polymer composition contained 46 mol% TFE and 54 mol% norbornene. A glass transition temperature of 152 ℃ as determined by DSC and an absorbance thereof at 157nm of 1.3 μm^-1It was confirmed that the copolymer had a lower glass transition temperature and a poorer transparency compared with the polymer of example 1 below.

Preparation of NB-TFE monomers used in the following examples:

NB-TFE monomer was prepared by reacting tetrafluoroethylene (1 equivalent) and norbornadiene (1.25 equivalents) in a sealed metal pressure vessel at 180 ℃ for 8 hours by essentially the same procedure as described in u.s.2,928,865 example 1. The product was purified by rotary zone distillation to give a pure fraction of the tricyclic comonomer (boiling point 67 ℃ C. at 45 mmHg).

Example 1: synthesis of the Polymer from monomers TFE and NB-TFE:

into a 200mL stainless steel pressure vessel were charged 46.1g NB-TFE, 75mL 1, 1, 2-trichlorotrifluoroethane and 1.0g Perkadox^*16N initiator. The vessel was closed, cooled in dry ice, evacuated and charged with 36g of Tetrafluoroethylene (TFE). The contents of the vessel were then stirred at 50 ℃ for 18 hr. The vessel was cooled to room temperature and vented to 1 atmosphere. Additional 1, 1, 2-trichlorotrifluoroethane was used to drain the translucent gelatinous solution from the vessel for rinsing. The material was allowed to air dry. The polymer was dissolved in tetrahydrofuran and precipitated into an excess of methanol. The solid was dried in a vacuum oven at 85 ℃ to give 18.0g of a white polymer; gpc (mek) Mn 9400, Mw 13100; Mw/Mn 1.40; tg 228 ℃ (DSC). And (4) analyzing to obtain: c, 46.26; h, 2.90; f, 49.80.¹⁹F NMR-95 to-122 (multiplet, 4F from TFE and 2F from NB-TFE), -124.4(dd, 2F from NB-F-OH). The polymer composition was calculated by integrating the lines and was 53% TFE and 47% NB-TFE. The absorbance at 157nm measured on a spin-cast film having a thickness of 88.4nm and 102.9nm was 0.69. mu.m^-1。

Example 2: synthesis of the Polymer from the monomers TFE, norbornene and NB-TFE:

following the procedure of example 1, 11.3g of norbornene, 23.0g of NB-TFE, 75mL of 1, 1, 2-trichlorotrifluoroethane, 1.0g of Perkadox were used^*16N and 36g TFE. The clear solution obtained by the polymerization was added to an excess of methanol. The precipitated polymer was dissolved in tetrahydrofuran and precipitated by adding the resulting solution to an excess of methanol. After drying, 21.2g of a white polymer was obtained; gpc (mek) Mn 6000, Mw 10500; Mw/Mn 1.73; tg166 Deg.C (DSC). And (4) analyzing to obtain: c, 53.07; h, 4.48; f, 41.80.¹⁹F NMR-95 to-122 (multiplet, 4F from TFE and 2F from NB-TFE) -124.4(dd, 2F from NB-F-OH). Integration of the lines shows a ratio of TFE to NB-TFE in the polymer of 74: 26.

Example 3: synthesis of the Polymer from monomers TFE, NB-F-OH and NB-TFE:

the monomer NB-F-OH was prepared using the following procedure:

a dry round bottom flask equipped with a mechanical stirrer, addition funnel and nitrogen inlet tube was purged with nitrogen and charged with 19.7g (0.78mol) of 95% sodium hydride and 500mL of anhydrous DMF. The stirred mixture was cooled to 5 ℃ and 80.1g (0.728mol) of exo-5-norbornen-2-ol were added dropwise to keep the temperature below 15 ℃. The resulting mixture was stirred for 1 hr. HFIBO (131g, 0.728mol) was added dropwise at room temperature (prepared as described in example 1 of PCT int. appl.WO 00/66575A 2 published 11.11.2001). The resulting mixture was stirred at room temperature overnight. Methanol (40mL) was added and most of the DMF was removed under reduced pressure in a rotary evaporator. The residue was treated with 200mL of water and glacial acetic acid was added until the pH was about 8.0. The aqueous mixture was extracted with 3X 150mL of diethyl ether. The combined ether extracts were washed with 3X 150mL of water and 150mL of brine, dried over anhydrous sodium sulfate and concentrated on a rotary evaporator to give an oil. Kugelrohr distillation at 0.15-0.20 torr and pot temperature 30-60 ℃ gave 190.1g (90%) of product.¹H NMR(δ，CD₂Cl₂)1.10-1.30(m, 1H), 1.50(d, 1H), 1.55-1.65(m, 1H), 1.70(s, 1H), 1.75(d, 1H), 2.70(s, 1H), 2.85(s, 1H), 3.90(d, 1H), 5.95(s, 1H), 6.25(s, 1H). Another sample prepared in the same manner was subjected to elemental analysis. C₁₁H₁₂F₆O₂Calculated values: c, 45.53; h, 4.17; f, 39.28. Experimental values: c, 44.98; h, 4.22; f, 38.25.

Example 4: synthesis of the Polymer from monomers TFE, NB-F-OH and NB-TFE:

the procedure of example 1 was followed, using 52.3g NB-F-OH, 11.5g NB-TFE, 75mL 1, 1, 2-trichlorotrifluoroethane, 1.0g Perkadox^*16N and 36g TFE. The clear solution obtained from the polymerization was added to an excess of hexane. The precipitated polymer was dried in a vacuum oven to obtain 12.0g of a white polymer; GPC (MEK) Mn 4800, Mw 6900; Mw/Mn1.45; tg 149 Deg.C (DSC). And (4) analyzing to obtain: c, 42.10; h, 3.42; f, 45.22.¹⁹FNMR-75.6(s, 6F from NB-F-OH), -95 to-122 (multiplet, 4F from TFE and 2F from NB-TFE), -124.4(dd, 2F from NB-TFE). The spectra were integrated and the polymer composition was calculated to contain 45% TFE, 47% NB-F-OH and 8% NB-TFE. The absorbance at 157nm measured on a spin-cast film having a thickness of 291.2nm and 235.1nm was 0.84. mu.m^-1。

Example 5: synthesis of the Polymer from the monomers TFE, NB-F-OH, NB-TFE and tert-butyl acrylate:

the procedure of example 1 was followed using 40.0g NB-F-OH, 5.8g NB-TFE, 1.54g tert-butyl acrylate, 75mL 1, 1, 2-trichlorotrifluoroethane, 0.6g Ferkadox^*16N and 42g TFE. The clear solution obtained from the polymerization was added to an excess of hexane. The precipitated polymer was dried in a vacuum oven to obtain 12.0g of a white polymer; GPC (MEK) Mn6200, Mw 9500; Mw/Mn 1.53; tg 146 Deg.C (DSC). And (4) analyzing to obtain: c, 44.36; h, 4.00; f, 40.16.¹⁹F NMR-75.6(s, 6F from NB-F-OH), -95 to-122 (multiplet, 4F from TFE and 2F from NB-TFE), -124.4(dd, 2F from NB-F-OH). Analyze it¹³C NMR spectrum calculated polymer composition containing 41% TFE, 39% NB-F-OH, 5% NB-TFE and 16% t-butyl acrylate. The absorbance at 157nm measured on spin-cast films of 101.9nm and 88.7nm in thickness was 1.73. mu.m^-1。

Example 6: synthesis of a suspected Compound from the monomers TFE, NB-F-OH, NB-F-O-MOM and NB-TFE:

the procedure of example 1 was followed using 34.8g NB-F-OH, 30.1g NB-F-O-MOM (demethoxylated)NB-F-OH protected with methyl ether, prepared by reacting NB-F-OH with chloromethyl methyl ether in the presence of a base), 5.8g NB-TFE, 75mL 1, 1, 2-trichlorotrifluoroethane, 1.0g Perkadox^*16N and 36g TFE. The clear solution obtained from the polymerization was added to an excess of hexane. The precipitated polymer was dried in a vacuum oven to obtain 10.4g of a white polymer; gpc (mek) Mn 5100, Mw 6900; Mw/Mn 1.35; tg 121 Deg.C (DSC). And (4) analyzing to obtain: c, 41.91; h, 3.50; f, 41.86.¹⁹F NMR-75.6(s, 6F from NB-F-OH), -73.8(s, 6F from NB-F-O-MOM), -95 to-122 (multiplet, 4F from TFE and 2F from NB-TFE), -124.4(dd, 2F from NB-F-OH). To it¹³The polymer composition was calculated by integrating the C NMR spectra and was 49% TFE, 26% NB-F-OH, 19% NB-F-O-MOM and 6% NB-TFE. The absorbance at 157nm measured on the spin-cast films having thicknesses of 100.2nm and 87.2nm was 1.11 μm^-1。

Example 7: homopolymer synthesis from monomer NB-TFE:

under nitrogen, mixing [ (. eta.) ]³-C₄H₇)PdCl]₂(0.338g, 0.862mmol) and AgSbF₆(0.596g, 17.2mmol) was dissolved in 20mL of chlorobenzene. The resulting mixture was stirred at room temperature for 40 minutes, during which time AgCl precipitated from the reaction mixture. The reaction mixture was filtered and the filtrate was added to a solution of NB-TFE (16.56g, 86.2mmol) dissolved in 100mL of chlorobenzene. The resulting solution was stirred at room temperature for 6 days, then poly (NB-TFE) was isolated by precipitation in hexane (500mL), then filtered and dried under vacuum. The yield of poly (NB-TFE) was 6.4 g. The spectral data are consistent with the vinyl addition polymers described below:

fluorine NMR showed two multiplets in a 1: 1 ratio:¹⁹f NMR (acetone-d)₆) -111.9 (multiplex), -125.3 (multiplex). GPC: mn 9340; mw 24425; Mw/Mn is 2.62. Preparation of 5% by weight of a 2-heptanone solutionThe liquid was used for spin coating, a thin film sample was spin coated, and the absorbance at 157nm was measured to give the following results: absorption coefficient at 157nm of 2.63 μm^-1. The absorbance coefficient at 157nm of the measured poly (NB-TFE) is orders of magnitude smaller than the reported absorbance coefficient of polynorbornene itself: for polynorbornene, the absorption coefficient at 157nm is 6.1. mu.m^-1[ see R.R.Kunz, T.M.Bloomstein, D.E.Hardy, R.B.Goodman, D.K.Downs, and J.E.Curtin, "157-nm Resist design expedition", Proc.SPIE-int.Soc.Opt.Eng., 3678(Pt.1, Advancin Resist Technology and Processing (Resist Technology and Processing evolution) XVI), pp.13-23, 1999]。

Example 8: imaging using poly (TFE/NB-F-OH/NB-TFE/tert-butyl acrylate):

the following formulation was prepared and stirred under magnetic force overnight:

component Wt. (gm)

Poly 0.483 prepared in example 5

(TFE/NB-F-OH/NB-TFE/tBA)

(41/39/5/16, made of¹³C NMR analysis)

2-heptanone 4.268

6.82% (wt) triphenylsulfonium 0.249 dissolved in 2-heptanone

NAFLATE solution, through 0.45 μm PTFE syringe

Filter filtration

Spin coating was performed on "P" -type <100> oriented silicon wafers having a diameter of 4in using a 100 CB-type combination spin coater/hot plate of Brewer Science inc. Development was performed on a Litho TechJapan Co. Resist Development Analyzer (model 790).

The wafers were prepared by depositing 5mL of Hexamethyldisilazane (HMDS) primer and spinning at 5000rpm for 10 seconds. 1-3mL of the above solution filtered through a 0.45 μm PTFE syringe filter was then deposited and spun at 3000rpm for 60 seconds and baked at 120 ℃ for 60 seconds.

248nm imaging was accomplished by exposing the coated wafer to light obtained as follows: broadband ultraviolet light generated by a solar simulator model ORIEL 82421 (1000W) passes through a 248nm interference filter passing about 30% of the energy at 248 nm. The exposure time was 180 seconds and a non-attenuating dose of 123mJ/cm was provided². By using a mask with 18 different neutral optical density positions, various exposure doses can be produced. After exposure, the exposed wafer was baked at 120 ℃ for 120 seconds. The wafer was developed in an aqueous tetramethylammonium hydroxide (TMAH) solution (OKA NMD-3, 2.38% aqueous TMAH solution) for 60 seconds to obtain an image pattern with a fixed transmittance of about 26mJ/cm²。

Example 9: imaging using poly (TFE/NB-F-OH/NB-TFE/tert-butyl acrylate):

the following formulation was prepared and stirred under magnetic force overnight:

component Wt. (gm)

Poly 0.433 prepared in example 5

(TFE/NB-F-OH/NB-TFE/tBA)

(41/39/5/16, made of¹³C NMR analysis)

2-heptanone 4.268

Lithocholic acid tert-butyl ester 0.050

6.82% (wt) triphenylsulfonium 0.249 dissolved in 2-heptanone

NAFLATE solution, through 0.45 μm PTFE syringe

Filter filtration

Working up was carried out as in example 8. Obtaining an erecting pattern with a penetrating dose of about 10mJ/cm²。

Example 10: imaging using poly (TFE/NB-F-OH/NB-F-O-MOM/NB-TFE):

the following formulation was prepared and stirred under magnetic force overnight:

component Wt. (gm)

Poly 0.483 prepared in example 6

(TFE/NB-F-OH/NB-TFE/NB-F-O-MOM)

(49/26/6/19, made of¹³C NMR analysis)

2-heptanone 4.268

6.82% (wt) of triphenyl 0.249 dissolved in 2-heptanone

Sulfonium nonaflate solution through 0.45 μm PTFE

Syringe filter filtration

Processing was carried out as in example 8, but with an exposure time of 30 seconds, providing an unattenuated dose of 20.5mJ/cm²And the post-exposure bake temperature is 100 ℃. An erecting pattern was obtained showing a partially settled dose of about 4.3mJ/cm²。

Example 11: imaging using poly (TFE/NB-F-OH/NB-F-O-MOM/NB-TFE):

the following formulation was prepared and stirred under magnetic force overnight:

component Wt. (gm)

Poly 0.408 prepared in example 6

(TFE/NB-F-OH/NB-TFE/NB-F-OMOM)

(49/26/6/19, made of¹³C NMR analysis)

2-heptanone 4.268

Lithocholic acid tert-butyl ester 0.075

6.82% (wt) of triphenyl 0.249 dissolved in 2-heptanone

Sulfonium nonaflate solution through 0.45 μm PTFE

Syringe filter filtration

Working up was carried out as in example 8. Obtaining an erecting pattern with a definite transmission dose of about 34mJ/cm²。

Claims (5)

1. A fluoropolymer comprising repeating units derived from at least one ethylenically unsaturated polycyclic compound of structure 1:

wherein:

R¹-R⁸each represents a hydrogen atom; m is 0, and

a repeating unit derived from a fluoroolefin, wherein the fluoroolefin is tetrafluoroethylene, chlorotrifluoroethylene, hexafluoroPropylene, trifluoroethylene, vinylidene fluoride, vinyl fluoride, perfluoro- (2, 2-dimethyl-1, 3-dioxole), perfluoro- (2-methylene-4-methyl-1, 3-dioxolane), CF₂＝CFO(CF₂)₁CF＝CF₂Wherein t is 1 or 2, or R_fOCF＝CF₂Wherein R is_fIs a saturated fluoroalkyl group containing 1 to 10 carbon atoms.

2. The fluoropolymer of claim 1 further comprising a fluoroalcohol group derived from at least one ethylenically unsaturated compound containing a fluoroalcohol group having the structure:

-C(R_f)(R_f’)OH

wherein R is_fAnd R_f' are identical or different fluoroalkyl radicals having from 1 to 10 carbon atoms or together form (CF)₂)_nWherein n is 2-10, these fluoroalkyl groups being designated as R_fAnd R_f', which may be partially fluorinated alkyl groups or fully fluorinated alkyl groups.

3. The fluoropolymer of claim 1 further comprising an acid-containing monomer having the structure:

wherein E₁Is H or C₁-C₁₂An alkyl group; e₂Is CO₂E₃，SO₃E or other acidic groups; and E₃Is H or C₁-C₁₂Alkyl, unsubstituted or heteroatom-substituted.

4. A photoresist comprising

(I) A fluoropolymer comprising repeating units derived from at least one ethylenically unsaturated polycyclic compound of structure 1:

wherein:

R¹-R⁸each represents a hydrogen atom;

m is a number of 0, and m is,

a fluoroolefin, wherein the fluoroolefin is tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, trifluoroethylene, vinylidene fluoride, vinyl fluoride, perfluoro- (2, 2-dimethyl-1, 3-dioxole), perfluoro- (2-methylene-4-methyl-1, 3-dioxolane), CF₂＝CFO(CF₂)_tCF＝CF₂Wherein t is 1 or 2, or R_fOCF＝CF₂Wherein R is_fA saturated fluoroalkyl group containing 1 to 10 carbon atoms, a fluoroalcohol group derived from at least one ethylenically unsaturated compound containing a fluoroalcohol group having the structure:

-C(R_f)(R_f’)OH

wherein R is_fAnd R_f' are identical or different fluoroalkyl radicals having from 1 to 10 carbon atoms or together form (CF)₂)_nWherein n is 2-10, these fluoroalkyl groups being designated as R_fAnd R_f', which may be a partially fluorinated alkyl group or a fully fluorinated alkyl group, and an acid-containing monomer having the structure:

wherein E₁Is H or C₁-C₁₂An alkyl group; e₂Is CO₂E₃，SO₃E or other acidic groups; and E₃Is H or C₁-C₁₂Alkyl, unsubstituted or heteroatom-substituted, and

(II) a photoactive component.

5. The photoresist of claim 4 further comprising a solvent and a dissolution inhibitor, and wherein the photoactive component is a photoacid generator.