JP2005520354A - Silicon-containing antireflection composition as a hard mask layer - Google Patents

Abstract

A novel anti-reflective coating / hard mask composition useful in lithography processes.
An antireflective composition characterized by the presence of a SiO-containing polymer having pendant chromophore moieties is an antireflective coating / hardmask composition useful in lithographic processes. This composition has outstanding optical properties, mechanical properties and etch selectivity and can be applied using spin-on coating techniques. This composition is particularly useful in lithographic methods used to mold underlying material layers on a substrate, particularly metal or semiconductor layers.

Description

  The present invention relates to the technical field of novel antireflective coating / hardmask compositions useful in lithography processes.

  In the microelectronics industry and other industries, including the construction of microstructures (eg, micromachines, magnetoresistive heads, etc.), there is an ongoing need to reduce the size of structural features. There is a need in the microelectronics industry to reduce the size of microelectronic devices and / or provide more circuitry for a given chip size.

  Effective lithography techniques are essential to achieve feature size reduction. Lithography has a major impact on the fabrication of microstructures, not only from directly forming a pattern on a desired substrate, but also from the production of masks commonly used in such imaging. Lithographic methods generally involve forming a patterned resist layer by exposing a radiation-sensitive resist in a pattern with imaging radiation. The image is then developed by contacting the exposed resist layer with a material (generally an aqueous alkaline developer) to selectively remove portions of the resist layer, thereby revealing the desired pattern. Subsequently, the pattern is transferred to the underlying material by etching the material in the openings in the patterned resist layer. After the transfer is completed, the remaining resist layer is removed.

  In some lithographic imaging methods, the resist used does not exhibit sufficient resistance to subsequent etching steps that allow the desired pattern to be effectively transferred to the underlying layer of the resist. In many cases (for example, if an ultra-thin resist layer is desired, if the underlying material to be etched is thick, if a significant etch depth is required, or use an etchant for a given underlying material A so-called hard mask layer is used between the resist material and the underlying material that forms the pattern by transfer from the patterned resist. The hard mask layer receives a pattern from the patterned resist layer. The hard mask layer must be able to withstand the etching process required to transfer the pattern to the underlying material.

  In addition, if the underlying material layer excessively reflects the imaging radiation used to form the pattern in the resist layer, it is generally possible to apply a thin anti-reflective coating between this underlayer and the resist layer. it can. In some cases, the anti-reflective function and the hard mask function are provided by the same material.

Although there are many hard masks and anti-reflective coating materials in the prior art, there is a continuing need for improved compositions. Many of these prior art materials are difficult to apply to substrates. These require, for example, the use of chemical or physical vapor deposition, or high temperature baking, or both. It would be desirable to have an anti-reflective coating / hard mask composition that can be applied by spin coating techniques and does not require high temperature baking. In addition, it can be selectively and easily etched with the photoresist above it, while being resistant to the etching methods required to form a pattern in the underlying layer, especially the underlying metal layer. A hard mask composition exhibiting
U.S. Pat. No. 4,371,605 US Pat. No. 5,100,503 JP-A-1-293339 Canadian Patent No. 1 204 547 US Pat. No. 5,886,102 US Pat. No. 5,939,236 US Pat. No. 5,861,231 US Pat. No. 5,962,184 US Pat. No. 6,037,097 U.S. Pat. No. 4,855,017 US Pat. No. 5,362,663 US Pat. No. 5,429,710 US Pat. No. 5,562,801 US Pat. No. 5,618,751 US Pat. No. 5,744,376 U.S. Pat. No. 5,801,944 US Pat. No. 5,821,469 US Pat. No. 5,948,570 Wayne Moreau, “Semiconductor Lithography, Principles, Practices, and Materials”, Plenum Press, (1988).

  The present invention includes novel antireflective coating / hardmask compositions useful in lithographic methods. This composition has outstanding optical properties, mechanical properties and etch selectivity and can be applied using spin-on coating techniques. This antireflective composition is characterized by the presence of a SiO-containing polymer having a pendant chromophore moiety. The present invention further includes a lithographic structure comprising the antireflective coating / hardmask composition of the present invention, a method of fabricating such a lithographic structure, and an underlying material layer on a substrate using such a lithographic structure. Includes a method of forming a pattern.

In one aspect, the invention includes a composition suitable for forming a spin-on antireflective layer. This composition is
(A) a polymer comprising a SiO moiety and a chromophore moiety;
(B) a crosslinking component;
(C) an acid generator.

  The SiO moiety is preferably selected from the group consisting of a siloxane moiety and a silsesquioxane moiety. The SiO portion is preferably in the main chain portion of the polymer. The SiO-containing polymer preferably further includes a plurality of reactive sites distributed along the polymer for reacting with the crosslinking component. The acid generator is preferably an acid generator activated by heat.

In another aspect, the invention includes a lithographic structure on a substrate. This structure is
(A) an antireflective layer comprising a crosslinked polymer comprising a SiO moiety and a chromophore moiety;
(B) a radiation sensitive imaging layer on the antireflective layer.

In another aspect, the invention includes a method of forming patterned material features on a substrate. This method
(A) providing a material layer on the substrate;
(B) forming an antireflective layer comprising a crosslinked polymer comprising a SiO moiety and a chromophore moiety on the material layer;
(C) forming a radiation sensitive imaging layer on the antireflective layer;
(D) subjecting the image forming layer to radiation exposure in a pattern, thereby producing a pattern of radiation exposed areas in the image forming layer;
(E) selectively removing a portion of the imaging layer and antireflective layer to expose a portion of the material layer; and (f) etching the exposed portion of the material layer, thereby patterning the material features. Including forming.

  The material for forming the pattern is preferably a conductor, semiconductor, magnetic material or insulator material, and more preferably a metal. The SiO portion is preferably in the main chain portion of the polymer. The SiO-containing polymer preferably further includes a plurality of reactive sites distributed along the polymer for reacting with the crosslinking component.

  The invention further includes a method of fabricating a lithographic structure.

  These and other aspects of the invention are discussed in more detail below.

  The present invention includes novel antireflective coating / hardmask compositions useful in lithographic methods. This antireflective composition is characterized by the presence of a SiO-containing polymer having a pendant chromophore moiety. The present invention further includes a lithographic structure comprising the antireflective coating / hardmask composition of the present invention, a method of fabricating such a lithographic structure, and an underlying material layer on a substrate using such a lithographic structure. Includes a method of forming a pattern.

The antireflective composition of the present invention is generally
(A) a polymer comprising a SiO moiety and a chromophore moiety;
(B) a crosslinking component;
(C) an acid generator.

  The polymer comprising a SiO moiety can be a polymer comprising a SiO moiety in the polymer backbone or pendant group, or both. The polymer containing the SiO part preferably contains the SiO part in the main chain. The polymer is preferably an organosiloxane, more preferably an organosilsesquioxane. The polymer must have dissolution / film formation properties that contribute to layer formation by conventional spin coating. In addition to the chromophore moieties discussed below, the SiO-containing polymer preferably includes a plurality of reactive sites distributed along the polymer to react with the crosslinking component.

  Examples of suitable polymers include polymers having a silsesquioxane (ladder or network) structure. Such polymers preferably include monomers having the following structures (I) and (II):

上式で、Ｒ_１は発色団を含み、Ｒ_２は、架橋成分と反応するための反応部位を含む。

Where R ₁ contains a chromophore and R ₂ contains a reactive site for reacting with a crosslinking component.

  Alternatively, more general linear organosiloxane polymers containing monomers (III) and (IV) can be used.

上式で、Ｒ_１およびＲ_２は先に説明したとおりである。場合によってはこのポリマーが、単量体（Ｉ）〜（ＩＶ）をさまざまな組合せで含む。そのため、Ｒ_１を含む単量体の平均構造を下記の構造（Ｖ）として表し、Ｒ_２を含む単量体の平均構造を下記の構造（ＶＩ）によって表すことができる。

In the above formula, R ₁ and R ₂ are as described above. In some cases, the polymer comprises monomers (I)-(IV) in various combinations. Therefore, the average structure of the monomer containing R ₁ can be represented as the following structure (V), and the average structure of the monomer containing R ₂ can be represented by the following structure (VI).

上式で、ｘは約１から約１．５である。理論的にはｘを１．５よりも大きくすることができるが、このような組成物は一般に、スピン・コーティング・プロセスに適した特性を持たない（たとえば望ましくないゲルまたは沈殿相を形成する）。

Where x is from about 1 to about 1.5. Although theoretically x can be greater than 1.5, such compositions generally do not have properties suitable for spin coating processes (eg, forming undesirable gels or precipitated phases). .

  In general, silsesquioxane polymers are preferred because of their excellent etching resistance. When ordinary organosiloxane polymers (eg monomers of structure (III) and (IV)) are used, it is preferred that the degree of cross-linking be higher than formulations based on silsesquioxane.

The group R ₁ comprising a chromophore can (i) be grafted to a SiO-containing polymer, (ii) have suitable radiation absorbing properties, and (iii) a layer comprising itself or above Any suitable chromophore can be included that does not adversely affect the performance of the photoresist layer. Preferred chromophore moieties include chrysene, pyrene, fluoranthenes, anthrone, benzophenone, thioxanthone and anthracene. Anthracene derivatives such as those described in US Pat. No. 4,371,605 can also be used. The disclosure of this patent is incorporated herein by reference. 9-anthracenemethanol is a preferred chromophore. It is preferred that the chromophore moiety is free of nitrogen, except for the possibly inactivated amino nitrogen, such as in phenol thiazine.

The chromophore moiety can be chemically coupled to the SiO-containing polymer by C-alkylation such as acid-catalyzed O-alkylation or Friedel-Crafts alkylation. Alternatively, it can be linked by an esterification mechanism. A preferred acid for Friedel-Crafts catalysis is HCl. It is preferred that about 15 to 40% of the functional groups (R ₁ ) contain a chromophore moiety. In some cases, the chromophore can be attached to the monomer prior to forming the SiO-containing polymer, but this is generally not preferred. The site to which the chromophore is bonded is preferably an aromatic group such as a hydroxybenzyl group or a hydroxymethylbenzyl group. Alternatively, the chromophore can be bound by reaction with other moieties such as cyclohexanol or other alcohols. The reaction for binding the chromophore is preferably esterification of an alcoholic OH group.

R ₂ includes a reactive site for reacting with the crosslinking component. A preferred reactive moiety contained in R ₂ is an alcohol, more preferably an aromatic alcohol (eg, hydroxybenzyl, phenol, hydroxymethylbenzyl, etc.) or an alicyclic alcohol (eg, cyclohexanoyl). Alternatively, acyclic alcohols such as fluorocarbon alcohols, aliphatic alcohols, amino groups, vinyl ethers, and epoxides can be used.

  The SiO-containing polymer (before chromophore bonding) is preferably poly (4-hydroxybenzylsilsesquioxane). Examples of other silsesquioxane polymers of the present invention include: poly (p-hydroxyphenylethylsilsesquioxane), poly (p-hydroxyphenylethylsilsesquioxane-co-p). -Hydroxy-α-methylbenzylsilsesquioxane), poly (p-hydroxyphenylethylsilsesquioxane-co-methoxybenzylsilsesquioxane), poly (p-hydroxyphenylethylsilsesquioxane-co-t -Butylsilsesquioxane), poly (p-hydroxyphenylethylsilsesquioxane-co-cyclohexylsilsesquioxane), poly (p-hydroxyphenylethylsilsesquioxane-co-phenylsilsesquioxane), Poly (p-hydroxyphenylethylsilsesquioki) -Co-bicycloheptylsilsesquioxane), poly (p-hydroxy-α-methylbenzylsilsesquioxane), poly (p-hydroxy-α-methylbenzylsilsesquioxane-co-p-hydroxybenzylsil) Sesquioxane), poly (p-hydroxy-α-methylbenzylsilsesquioxane-co-methoxybenzylsilsesquioxane), poly (p-hydroxy-α-methylbenzylsilsesquioxane-co-t-butyl) Silsesquioxane), poly (p-hydroxy-α-methylbenzylsilsesquioxane-co-cyclohexylsilsesquioxane), poly (p-hydroxy-α-methylbenzylsilsesquioxane-co-phenylsilsesquito) Oxane), poly (p-hydroxy-α-methylbenzylsilsesqui) Hexane -co- bicycloheptyl silsesquioxane), and poly (p- hydroxybenzyl silsesquioxane -co-p-hydroxyphenyl-ethyl silsesquioxane). The polyorganosiloxane polymers described in US Pat. No. 5,100,503 are generally not effective in producing low temperature baking compositions because of their very low reactivity with the crosslinking component. The disclosure of this patent is incorporated herein by reference.

  The weight average molecular weight of the inventive SiO-containing polymer before reacting with the crosslinking component is preferably at least about 1000, more preferably about 1000 to 10,000.

  The cross-linking component is preferably a cross-linking agent capable of reacting with the SiO-containing polymer by catalysis by the generated acid and / or by heating. In general, the crosslinking component used in the antireflective composition of the present invention can be any suitable crosslinking agent known in the field of negative photoresists that is compatible with the other selected components of the composition. The cross-linking agent preferably functions to cross-link the polymer component in the presence of the generated acid. Preferred cross-linking agents include tetramethoxymethyl glycoluril, methylpropyltetramethoxymethylglycoluril, methylphenyltetramethoxymethylglycoluril sold under the trademark POWDERLINK by American Cyanamid Company, etc. The glycoluril compound. Other possible crosslinkers include 2,6-bis (hydroxymethyl) -p-cresol compounds having the following structure:

これにはさらに、特開平１−２９３３３９に記載されているような上記化合物の類似体および誘導体、エーテル化されたアミノ樹脂、たとえばメチル化またはブチル化されたメラミン樹脂（Ｎ−メトキシメチルメラミンまたはＮ−ブトキシメチルメラミン）、またはたとえばカナダ特許番号１ ２０４ ５４７に出ているメチル化／ブチル化されたグリコールウリルが含まれる。ビスエポキシ、ビスフェノール（たとえばビスフェノールＡ）など、他の架橋剤を使用することもできる。架橋剤の組合せを使用することもできる。

Further to this are analogs and derivatives of the above compounds as described in JP-A-1-293339, etherified amino resins, such as methylated or butylated melamine resins (N-methoxymethylmelamine or N -Butoxymethylmelamine), or methylated / butylated glycoluril, e.g. as found in Canadian Patent No. 1204547. Other crosslinkers such as bisepoxy, bisphenol (eg, bisphenol A) can also be used. Combinations of crosslinkers can also be used.

  The acid generator is preferably an acid-generating compound that releases an acid upon heat treatment. Various known thermal acid generators such as 2,4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, and other alkyl esters of organic sulfonic acids are suitably used. use. In general, compounds that produce a sulfonic acid upon activation are suitable. Other suitable heat activated acid generators are described in US Pat. Nos. 5,886,102 and 5,939,236. The disclosures of these two patents are incorporated herein by reference. If desired, a radiation-sensitive acid generator can be used in place of or in combination with a heat-activated acid generator. Examples of suitable radiation sensitive acid generators are described in US Pat. Nos. 5,886,102 and 5,939,236. Other radiation sensitive acid generators known in the resist art can be used as long as they are compatible with the other components of the antireflective composition. When a radiation sensitive acid generator is used, the curing (crosslinking) temperature of the composition can be lowered by irradiating with an appropriate radiation that causes generation of an acid that catalyzes the crosslinking reaction. Even when a radiation sensitive acid generator is used, it is preferred to heat treat the composition to accelerate the crosslinking process (eg, the crosslinking process of wafers in a production line).

  The antireflective composition of the present invention (on a solids basis) comprises (i) about 50-98 wt%, more preferably about 70-80 wt% SiO-containing polymer, and (ii) about 1-50 wt%, More preferably comprises about 3-25% by weight, most preferably about 5-25% by weight of a crosslinking component and (iii) about 1-20% by weight, more preferably about 1-15% by weight of an acid generator. It is preferable.

  The antireflective coating / hardmask composition of the present invention can be used in combination with a desired resist material in the formation of a lithographic structure. The resist is preferably imageable with ultraviolet radiation (eg, wavelength <400 nm) or electron beam radiation. Examples of suitable resist materials are described in US Pat. Nos. 5,861,231, 5,962,184 and 6,370,977. The disclosures of these patents are incorporated herein by reference.

  The antireflective composition of the present invention prior to application to the desired substrate generally contains a solvent. The solvent can be used in the conventional manner together with the resist, and can be a solvent that does not have an extremely harmful influence on the performance of the antireflection composition. Preferred solvents are propylene glycol monomethyl ether acetate, cyclohexanone and ethyl cellosolve acetate. The amount of the solvent in the composition intended to be applied to the substrate is preferably sufficient so that the solid content is about 8 to 20% by weight. In general, the thicker the coating layer, the higher the solid content of the preparation. The compositions of the present invention can contain minor amounts of auxiliary ingredients (such as base additives) known in the art.

  The antireflective composition of the present invention can be prepared by combining the polymer, crosslinking component, acid generator and other desired ingredient components using conventional methods. The composition of the present invention can be advantageously converted to an antireflective layer on the substrate by spin coating and subsequent baking to achieve cross-linking / solvent removal. Baking is preferably performed at about 250 ° C. or less, more preferably about 150 ° C. to 200 ° C., and most preferably about 170 ° C. to 180 ° C. The baking time can be changed according to the layer thickness and baking temperature. The baking time at 170 ° is generally about 2 minutes.

  The thickness of the antireflective composition of the present invention can be changed according to the desired function. For example, if the composition is used as a non-planarized antireflective coating, the thickness can be about 50-500 nm. When used as a planarizing hard mask, the thickness is preferably about 0.5 to 5.0 μm. If desired, the composition of the present invention can be used as a dielectric material in the same manner as conventional spin-on glass materials.

  The compositions of the present invention are particularly useful for lithographic methods used in the manufacture of integrated circuits on semiconductor substrates. This composition is particularly useful for lithographic methods using mid-UV, 248 nm deep ultraviolet, X-rays, e-beams or other imaging radiation.

  Semiconductor lithography applications generally involve the transfer of a pattern to a material layer on a semiconductor substrate. The material layer of the semiconductor substrate is a metal conductor layer, ceramic insulator layer, semiconductor layer or other material depending on the stage of the manufacturing process and the desired material set for the final product. The composition of the invention is preferably applied directly onto the material layer to be patterned, preferably by spin coating. The composition is then baked to remove the solvent and cure (crosslink) the composition. A radiation sensitive resist layer can then be applied (directly or indirectly) onto the cured antireflective composition of the invention.

  In general, a solvent-containing resist composition is applied using spin coating or other techniques. Preferably, the substrate with the resist coating is then heated (pre-exposure bake) to remove the solvent and improve the coherence of the resist layer. The thickness of the applied resist layer is preferably as thin as possible, but this thickness is preferably substantially uniform, and the resist layer is used for transferring the lithography pattern to the underlying substrate material layer. Must be sufficiently resistant to this process (generally reactive ion etching). This pre-exposure bake step is preferably performed for about 10 seconds to 15 minutes, more preferably about 15 seconds to 1 minute. The pre-exposure baking temperature can be changed according to the glass transition temperature of the photoresist.

After removing the solvent, the resist layer is exposed in a pattern with the desired radiation (eg, 248 nm ultraviolet radiation). When using a scanning particle beam, such as an electron beam, this patternwise exposure can be achieved by scanning the beam over the substrate and selectively applying the beam to the desired pattern. In the case of more general wave radiation such as 248 nm ultraviolet radiation, this pattern exposure is performed through a mask placed on the resist layer. For 248 nm UV radiation, the total exposure energy is preferably about 100 millijoules / cm ² or less, more preferably about 50 millijoules / cm ² or less (eg, 15-30 millijoules / cm ² ).

  In general, after the desired exposure in a pattern, the resist layer is baked to complete the acid-catalyzed reaction and enhance the contrast of the exposed pattern. This post-exposure baking is preferably performed at about 60 to 175 ° C, more preferably about 90 to 160 ° C. This post-exposure baking is preferably performed for about 30 seconds to 5 minutes.

  After post-exposure baking, the resist layer is contacted with an alkaline solution that selectively dissolves areas of the resist exposed to radiation to obtain (develop) a resist structure having the desired pattern. A preferred alkaline solution (developer) is an aqueous solution of tetramethylammonium hydroxide. The lithographic structure on the substrate is then typically dried to remove residual developer.

The pattern of the resist structure is then transferred to the exposed portion of the layer of the antireflective material of the present invention by etching with CF ₄ or other suitable etchant using techniques known in the art. be able to.

After opening the layer of antireflective material of the present invention and any antireflective coating below it, the underlying material layer to be patterned is etched using an etchant appropriate for the composition of the material layer. be able to. When the material layer is a metal (eg, Cr), a Cl ₂ / O ₂ mixture can be used as a dry etchant.

Once the desired pattern transfer is complete, the remaining resist can be removed using conventional stripping techniques. If the composition of the present invention is strictly used as a hard mask or non-planarized antireflective coating, the composition of the present invention can be removed by contact with a CF ₄ / O ₂ plasma.

  Thus, using the compositions of the present invention and the resulting lithographic structure, holes for metal wiring, contacts or vias, insulators (eg, damascene trenches or shallow trenches) used in integrated circuit device designs. Isolation), patterned material layer structures such as trenches for capacitor structures can be created. The compositions of the present invention are particularly useful in the context of producing patterned metal structures, particularly Cr-based structures useful as masks.

  Examples of common lithographic methods in which the compositions of the present invention may be useful are U.S. Pat. Is disclosed. The disclosures of these patents are incorporated herein by reference. Other examples of pattern transfer methods are described in Chapters 12 and 13 of Wayne Moreau's “Semiconductor Lithography, Principles, Practices, and Materials”, Plenum Press, (1988). The disclosure of this document is incorporated herein by reference. It should be understood that the present invention is not limited to a particular lithographic technique or device structure.

Ortho-grafting of 9-anthracene methyl group to poly (4-hydroxybenzylsilsesquioxane) and hard mask / antireflective layer formulation In 150 g of acetonitrile containing 0.4 g of HCl, 6.7 g of 9-anthracene methanol was added. And 16 g of poly (4-hydroxybenzylsilsesquioxane). The solution was heated to reflux for several hours and then water was added to precipitate the grafted polymer. This dried polymer was dissolved in propylene glycol monomethyl ether acetate (PGMEA) to give a 14 wt% solution. To this solution were added glycoluril resin (POWDERLINK crosslinking agent) and nitrobenzyl tosylate (acid generator) in amounts of 10% by weight of total solids and 5% by weight of solids, respectively. To this solution was further added 200 ppm of FC430 surfactant (sold by 3M Corporation).

CF ₄ / _{O 2} hardmask / antireflective layer using a gas and hardmask / antireflection layer was prepared as described in etching Example 1 UV-80 a (HM / ARC), hexamethyldisilazane (HMDS ) Was spin coated at 3000 rpm. The spin-coated film was cured at 175 ° C. for 3 minutes. A layer of UV-80 photoresist (sold by Shipley Company) was spin coated at 3000 rpm on the cured layer. This photoresist layer was soft baked at 130 ° C. for 60 seconds.

The thickness was measured using a profilometer. A 13.0 nm Al strip was used as a mask to measure the thickness. This Al is not etched by either Cl ₂ / O ₂ plasma or CF ₄ / O ₂ plasma.

A generic oxide etching method was used with CF ₄ / O ₂ etching using the conditions in Table I. A low pressure high density plasma method using inductively coupled plasma (ICP) was used. The flow rate, pressure, power, and Ar dilution were selected to provide a relatively stable process that did not produce the vibrations often encountered with these electronegative discharges. The DC self-bias voltage was maintained at 150 volts.

Etching HM / ARC and UV80 hardmask / antireflective layer and UV80 using Cl ₂ / _{O 2} gas, in addition to using the etching method described in Table III were treated in the same manner as in Example 2.

  The etching rate of HM / ARC is much smaller than UV-80.

Claims (10)

A composition suitable for forming a spin-on antireflection layer,
(A) a polymer comprising a SiO moiety and a chromophore moiety;
(B) a crosslinking component;
(C) A composition comprising: an acid generator.   The composition of claim 1 wherein the SiO moiety is selected from the group consisting of a siloxane moiety and a silsesquioxane moiety.   The composition according to claim 1, wherein the acid generator is an acid generator activated by heat.   The composition of claim 1, wherein the SiO-containing polymer further comprises a plurality of reactive sites distributed along the polymer to react with the cross-linking component.   The composition of claim 1, wherein the chromophore moiety is selected from the group consisting of chrysene, pyrene, fluoranthene, anthrone, benzophenone, thioxanthone and anthracene.   The composition of claim 1, wherein the crosslinking component comprises a glycoluril compound.   The composition of claim 1, wherein the SiO moiety is in the main chain portion of the polymer.   An antireflection layer comprising a composition according to any one of claims 1 to 7 in a crosslinked form on a substrate. A method of forming a patterned material feature on a substrate, comprising:
(A) providing a material layer on the substrate;
(B) forming an antireflective layer containing the composition according to any one of claims 1 to 7 in a crosslinked form on the material layer;
(C) forming a radiation-sensitive image forming layer on the antireflection layer;
(D) subjecting the image forming layer to radiation exposure in a pattern, thereby producing a pattern of radiation exposed areas in the image forming layer;
(E) selectively removing a portion of the imaging layer and antireflective layer to expose a portion of the material layer; and (f) etching the exposed portion of the material layer, thereby patterning. Forming the material feature.   The radiation is selected from the group consisting of (a) ultraviolet radiation having a wavelength shorter than 250 nm and (b) electron beam radiation, and in step (b) the antireflection layer is in any of claims 1-7. 10. The method of claim 9, wherein the method is formed by spin-coating the composition described above and subsequently crosslinking the composition.