KR20060088478A - Photoresist polymers and compositions having acrylic- or methacrylic-based polymeric resin prepared by a living free radical process - Google Patents

Abstract

The present invention is directed to the preparation of photoresist polymers via living free radical polymerization techniques. Sterically bulky ester monomers are utilized as the polymerization components. Use of chain transfer agents is included in polymerization processing conditions. Cleavage of polymer terminal end groups that include a heteroatom are described.

Description

PHOTORESIST POLYMERS AND COMPOSITIONS HAVING ACRYLIC- OR METHACRYLIC-BASED POLYMERIC RESIN PREPARED BY A LIVING FREE RADICAL PROCESS}

Methods of patterning semiconductor wafers typically rely on lithographic transfer of a desired image from a thin film of photosensitive resist material. The method includes the formation of a sacrificial layer (“resist”) that is photolithographic patterned. Generally these resists are referred to as "photoresists".

Patterning of the resist involves several steps, including exposing the resist to a selected light source through an appropriate mask to record a latent image of the mask; Developing step; And removing the selected region of the resist. For "positive" resists, the exposed areas change so that exposed areas can be selectively removed, while for "negative" resists, unexposed areas can be more easily removed.

The pattern can be transferred to the surface texture of the wafer by etching with reactive gas while using the remaining patterned resist as a protective masking layer. Alternatively, when the wafer is "masked" by a resist pattern, it can be processed to form active electronic devices and circuits by deposition of conductive or semiconducting materials or by implantation of dopants.

The materials used in single layer photoresists for optical lithography must serve several purposes. Low optical density at exposure wavelengths and resistance in image transfer processes such as plasma etching are two important objectives that such photoresist materials must meet. Shorter irradiation wavelengths enable higher resolutions. The most common wavelengths currently used in semiconductor lithography are 365 nm and 248 nm, with 193 nm being widely used in recent years. The need for narrower line widths and higher resolutions has raised interest in photoresist materials that can be patterned by shorter light wavelengths.

In the field of microfabrication, the processing size is getting finer in order to achieve higher integration. Recently, the development of lithographic methods that enable stable microfabrication with line widths of 0.5 microns, more preferably 0.2 microns or less, has been actively received.

Conventional lithography methods use near ultraviolet radiation, such as i-line radiation. However, it is difficult to form fine patterns with high accuracy using conventional methods using visible light (wavelength: 700-400 nm) or near ultraviolet light (wavelength: 400-300 nm). To address this problem, lithographic methods have been developed that use irradiation with shorter wavelengths (wavelengths below 300 nm). Such shorter wavelength radiation is effective in achieving a range of focal depths and ensuring design rules with minimum dimensions.

X-rays such as synchrotron radiation, charge particle beams (electron beams, etc.), as well as short wavelength radiation, ultra-short wavelengths of ultraviolet light (e.g., KrF excimer laser (wavelength: 248 nm) or ArF excimer laser (wavelength: 193 nm)) Examples) can be used.

As a resist applicable to excimer laser radiation, a chemical amplification effect between a component having an acid-decomposable functional group and an acid generating component (hereinafter referred to as "light acid generator") that generates light upon irradiation (hereinafter referred to as "exposure") A number of resists have been proposed that use. Such resists are referred to below as chemically amplified resists.

Japanese Patent Laid-Open No. 2-27660 discloses a chemically amplified resist containing a photo acid generator and a polymer having a t-butyl ester group of carboxylic acid or a t-butylcarbonate group of phenol. The t-butyl ester group or t-butyl carbonate group in the polymer is decomposed by the action of an acid generated during exposure, whereby the polymer has acidic groups such as carboxyl groups or phenolic hydroxyl groups. As a result, the exposed area of the resist film becomes easily soluble in the alkaline developer.

Generally, conventional KrF chemically amplified resists contain phenolic resins as base resins. However, phenolic resins do not effectively reach the lower part of the last film due to the strong absorption of the ArF laser line by the aromatic ring, so that the irradiation amount is increased in the upper part of the resist film and decreased in the lower part. Not suitable for use in ArF photoresist. As a result, the resist pattern after development is trapezoidol, which results in a thinner pattern on the upper part and a thicker resist pattern on the lower part. Sufficient resolution is generally not obtained. If the resist pattern after development is trapezoidal in shape, the desired dimensional accuracy cannot be achieved in subsequent steps such as etching step or ion implantation step. In addition, when the shape of the upper portion of the resist pattern is not rectangular, the removal rate by dry etching of the resist is increased, thereby making it difficult to control the etching conditions.

The shape of the resist pattern can be increased by increasing the radiation transmittance of the resist film. For example, (meth) acrylate resins such as polymethylmethacrylate are very preferred resins in view of irradiation transmittance because the (meth) acrylate resins have high transparency to ultraviolet rays of extreme wavelengths. For example, Japanese Patent Application Laid-Open No. 4-226461 discloses a chemically amplified resist using methacrylate resin. However, this composition works well in microfabrication performance but has insufficient dry etch resistance due to the absence of aromatic rings. This makes it difficult to perform etching with high accuracy. Thus, a composition having both transparency to radiation and dry etching resistance is not provided in this manner.

As a means for improving the dry etching resistance of chemically amplified resists without impairing transparency to radiation, a method of introducing aliphatic rings into the resin component of the resist polymer instead of aromatic rings has been studied. For example, Japanese Patent Application Laid-Open No. 7-234511 discloses a chemically amplified resist using a (meth) acrylate resin having an aliphatic ring.

In order to further improve ArF photoresist performance, one or more repeating unit (s) have been introduced into the resins described above. For example, Japanese Patent 3042618 discloses a chemically amplified resist using a resin by introducing a repeating unit having a lactone skeleton. Japanese Patent Application Laid-Open No. 2002-296783A discloses a chemically amplified resist using a resin by introducing repeating units than those described above.

However, the (meth) acrylate-based photoresist resins discussed so far are prepared by conventional free radical polymerization methods. See, eg, US Pat. Nos. 6,013,416, 6,087,063, 6,207,342, 6,303,266, and 6,596,458, incorporated herein by reference. As both the molecular size and polarity of the monomer's chemical structure are very different, copolymerizing them by conventional free radical polymerization introduces several drawbacks to the molecular properties of the resin: (1) wide polydispersity (2) polymer chains (3) difficulty in controlling the reproducibility of polymerization between monomer drift.

There is a need in the art for new polymeric materials that are transparent for use in DUVs that are transparent enough to transmit activating light and withstand additional processing conditions.

There is also a need for a polymer resin that overcomes one or more of the above mentioned disadvantages of currently available photoresist polymer resins.

Summary of the Invention

(여기서, R^x는 그 자유 라디칼 형태로서 방출되기에 충분히 불안정한 기이고, T는 탄소 또는 인이고, Z는 C=S 이중 결합이 가역적 자유 라디칼 부가 단편화 반응을 할 수 있도록 활성화시키는 임의의 기임)를 갖는 사슬 이동제 (CTA)의 존재하에 리빙 자유 라디칼 공정 (LFRP)에 의해 제조되는 중합체를 제공한다. In one aspect, the present invention comprises an acrylic or methacrylic monomer unit of formula (1),

Where R ^x is a group that is unstable enough to be released as its free radical form, T is carbon or phosphorus, and Z is any group that activates a C = S double bond to enable a reversible free radical addition fragmentation reaction. Provided is a polymer prepared by Living Free Radical Process (LFRP) in the presence of a chain transfer agent (CTA).

R ¹ represents a hydrogen atom or a methyl group,

Each R ² is individually linear or branched, unsubstituted or substituted alkyl group of 1-4 carbon atoms, or bridged or unbridged, unsubstituted or substituted monovalent aliphatic hydrocarbon group of 4-20 carbon atoms, provided that two R ² groups wherein the two R ² groups form a 4 to 20 carbon atoms in the bridge, or non-bridge, unsubstituted or substituted bivalent aliphatic hydrocarbon ring together with the binding carbon atoms and the remaining R ² is a linear or branched, substituted Unsubstituted or substituted alkyl groups of 1-4 carbon atoms.

In certain embodiments, Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof.

In another embodiment, Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally substituted Heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl.

The polymer resin of the present invention may further comprise one or more additional repeating units of formula (2).

Wherein E is a group derived from an unbridged or bridged, unsubstituted or substituted aliphatic ring hydrocarbon, and R ³ is a hydrogen atom, a trifluoromethyl or methyl group.

(여기서, R^x, T 및 Z는 상기 정의된 바와 같음)을 갖는 사슬 이동제 (CTA)의 존재하에 리빙 자유 라디칼 공정에 의해 제조되는 것인 포토레지스트 조성물에 관한 것이다. In another aspect, the invention comprises (A) a photo-acid generator and (B) an acrylic or methacrylic polymer resin, wherein the polymer

A photoresist composition is prepared by a living free radical process in the presence of a chain transfer agent (CTA) with R ^x , T and Z as defined above.

In certain embodiments, Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof.

In another embodiment, Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally substituted Heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl.

In a further aspect, the polymeric resin of the photoresist composition may comprise repeating units of Formula 1 above.

The polymer resin of the photoresist composition may further include one or more additional repeating units of Formula 2 described above.

Polymeric resins (such as of photoresist compositions) generally have a molecular weight of about 2,000 to about 30,000. In addition, the polymer resin generally has a polydispersity of about 1.5 or less. Finally, the polymer resins produced by the process of the invention generally comprise CTA fragments that can be degraded by the process disclosed throughout the specification.

In general, the polymers of the present invention are random copolymers and may be prepared under batch processes or under semi-continuous polymerization reaction conditions.

In another aspect of the invention, the polymer (eg, of the photoresist composition) has a polydispersity index of less than about 1.7, more specifically from about 1.2 to about 1.4. The molecular weight (Mw) of the polymers of the invention ranges from about 2,000 to about 30,000.

Both acrylic and methacryl type resins having stereoscopically bulky ester groups (including esters and mixtures thereof) are encompassed by the present invention and are useful for coating applications such as, for example, photoresist materials.

In certain aspects of the invention, the polymer resin (eg, of the photoresist composition) is insoluble or weakly soluble in alkali, but alkali soluble by the action of an acid.

(R'은 CN 또는 COOMe)을 가지는 종결기를 포함하도록 분해 조건을 거치게 할 수도 있다. 다르게는, 말단 위치는 선택된 조건에 따라 수소 원자, 모노머 단위 또는 RAFT기로 캡핑될 수 있다. In another aspect of the invention, the terminal position of the polymer resin (acrylic or methacryl derivative) (eg, of the photoresist composition) comprises a thiocarbonylthio moiety. The thiocarbonylthio moiety is also in one embodiment a terminal position of the polymer

(R ′ may be subject to degradation conditions to include terminators having CN or COOMe). Alternatively, the terminal position may be capped with a hydrogen atom, a monomer unit or a RAFT group depending on the conditions selected.

Although disclosed in a number of embodiments, other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description showing and describing exemplary embodiments of the present invention. As will be appreciated, the present invention may be modified in various obvious respects without departing from its spirit and scope. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature, and not as restrictive.

This application discloses pending US patent application Ser. No. _________ (title “Photoresist Polymer Composition”, Didier Benoit et al., Filed Jun. 25, 2004), and US Patent Application No. ________, the contents of which are incorporated herein by reference. (Title “photoresist polymer”, Didier Benoit et al., Filed June 25, 2004).

High absorbance at 193 or 157 nm limits light transmission into the resist and makes it difficult to expose complete resist to the base of the resist. Without full resist exposure, the resist is not properly imaged. If the resist becomes thin enough to ensure full exposure, it may not be thick enough to withstand subsequent processing steps such as plasma etching or ion implantation. To compensate for this problem, resist designers frequently seek to find that a sufficiently thin resist is a multilayer resist deposited on top of a more photoreactive second resist. Although this composite resist is effective, the resolution is compromised by undercutting or widening of the exposed areas during development. The present invention provides methods and materials for making single or multilayer thin film resists that are thick enough to withstand etching and / or other post-exposure processing steps and thin enough to transmit light to the base of the resist. Conventional aqueous developers can be used to remove the base soluble polymers that have been exposed after exposure to a source of irradiation energy.

The ability to form a photolithographic pattern is defined by Rayleigh formula, where R represents the resolution or line width of the optical system. Rail-ray type

R = kλ / NA

Is the exposure wavelength, NA is the numerical aperture of the lens, and k is the process factor. It should be understood from the Rayleigh equation that the exposure wavelength λ must be small to achieve higher resolution or to obtain a smaller R. For example, high pressure mercury vapor lamps are known to emit a defined band of radiation ("i-line") at a wavelength of 365 nm. Mercury vapor lamps have been used as light sources for the manufacture of dynamic random access memory (DRAM) with integration levels of up to 64M bits. Similarly, KrF excimer lasers that emit irradiation energy at a wavelength of 248 nm are commonly used for mass production of 256-bit DRAM devices. This fabrication process requires a machining dimension of less than 0.25 microns. Shorter wavelengths are required for the fabrication of DRAMs with densities greater than 1 Gbit. Such a device would require a processing dimension of less than 0.2 micron. For this purpose, other excimer lasers such as KrCl lasers with wavelengths of 222 nm, ArF lasers with wavelengths of 193 nm, and F2 lasers with wavelengths of 157 nm are currently under investigation.

(여기서, R^x는 그 자유 라디칼 형태로서 방출되기에 충분히 불안정한 기이고, T는 탄소 또는 인이고, Z는 C=S 이중 결합이 가역적 자유 라디칼 부가 단편화 반응을 할 수 있도록 활성화시키는 임의의 기임)를 갖는 사슬 이동제 (CTA)의 존재하에 리빙 자유 라디칼 공정 (LFRP)에 의해 제조되는 중합체를 제공한다. In one aspect, the present invention comprises an acrylic or methacrylic monomer unit of formula (1),

Where R ^x is a group that is unstable enough to be released as its free radical form, T is carbon or phosphorus, and Z is any group that activates a C = S double bond to enable a reversible free radical addition fragmentation reaction. Provided is a polymer prepared by Living Free Radical Process (LFRP) in the presence of a chain transfer agent (CTA).

<Formula 1>

R ¹ represents a hydrogen atom or a methyl group,

Each R ² is individually linear or branched, unsubstituted or substituted alkyl group of 1-4 carbon atoms, or bridged or unbridged, unsubstituted or substituted monovalent aliphatic hydrocarbon group of 4-20 carbon atoms, provided that two R ² groups wherein the two R ² groups form a 4 to 20 carbon atoms in the bridge, or non-bridge, unsubstituted or substituted bivalent aliphatic hydrocarbon ring together with the binding carbon atoms and the remaining R ² is a linear or branched, substituted Unsubstituted or substituted alkyl groups of 1-4 carbon atoms.

In certain embodiments, Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof.

In another embodiment, Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally substituted Heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl.

In a further aspect, the polymeric resin of the present invention may further comprise one or more additional repeat units of formula (2).

<Formula 2>

Wherein E is a group derived from an unbridged or bridged, unsubstituted or substituted aliphatic ring hydrocarbon, and R ³ is a hydrogen atom, a trifluoromethyl or methyl group.

(여기서, R^x, T 및 Z는 상기 정의된 바와 같음)을 갖는 사슬 이동제 (CTA)의 존재하에 리빙 자유 라디칼 공정에 의해 제조되는 것인 포토레지스트 조성물을 제공한다. In another aspect, the present invention comprises a photo-acid generator and an acrylic or methacrylic polymer resin, wherein the polymer

A photoresist composition is prepared by a living free radical process in the presence of a chain transfer agent (CTA) with R ^x , T and Z as defined above.

In certain embodiments, Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof.

In another embodiment, Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally substituted Heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl.

In a further aspect, the photoresist composition comprises a polymer resin and a photo-acid generator that may include repeating units of Formula 1 above.

The polymer resin (eg, of the photoresist composition) may further include one or more additional repeating units of Formula 2 described above.

The polymer resin (eg, of the photoresist composition) generally has a molecular weight of about 2,000 to about 30,000. In addition, the polymer resin generally has a polydispersity of about 1.5 or less. Finally, the polymer resins produced by the process of the invention generally comprise CTA fragments that can be degraded by the process disclosed throughout the specification.

It is to be understood that all combinations of monomers (and monomer units derived from polymers provided herein) are within the scope of the present invention.

In one aspect, the polymer resin (eg, of the photoresist composition) is insoluble or weakly soluble in alkali, but is alkali soluble by the action of an acid. The polymer resin of Formula 1 is prepared by LFRP in the presence of CTA, as described throughout this specification, as described above. This polymer resin is hereinafter referred to as "polymer resin (A)".

As used herein, the term “insoluble or weakly soluble in alkali” is used when forming a resist pattern using a resist film formed of a photosensitive resin composition comprising resin (A) (eg, of a photoresist composition). When developing a resist film consisting only of resin (A) (eg, of a photoresist composition) under alkaline developing conditions, it refers to a property in which at least 50% of the initial film thickness remains after development.

The polymer resin (A) (eg, of the photoresist composition) may include one or more additional repeating monomer units described throughout this specification. For example, these repeating units include those described above, such as those having Formula 2 as described above.

이 있다. 상기한 -C(R²)₃기가 중합체 수지(A) (예컨대, 포토레지스트 조성물의)에 개별적으로 또는 하나 이상의 부가적인 모노머와 함께 존재할 수 있다고 이해되어야 한다. As specific examples of the group represented by -C (R ² ) ₃ in the repeating unit (1), a t-butyl group and a group of the formula below, or substituted ones thereof,

There is this. It is to be understood that the aforementioned -C (R ² ) ₃ groups can be present individually in the polymer resin (A) (eg of the photoresist composition) or with one or more additional monomers.

E in formula (2) is a group derived from an unbridged or bridged aliphatic ring hydrocarbon, more preferably a cyclohexane, norbornane, tricyclodecane, adamantane or a compound in which at least one hydrogen of these groups is substituted by a methyl group Group derived from.

Suitable examples of the E structure in formula (2) include a hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, 1-hydroxy-n-propyl group, 2-hydroxy-n-propyl group, 3-hydroxy -n-propyl group, 1-hydroxy-n-butyl group, 2-hydroxy-n-butyl group, 3-hydroxy-n-butyl group, 4-hydroxy-n-butyl group, 3-hydroxy Cyclopentyl group, 4-hydroxycyclohexyl group, 5-hydroxy-2-norbornyl group, 8-hydroxy-3-tricyclodecanyl group, 8-hydroxy-3-tetracyclododecanyl group, 3- Hydroxy-1-adamantyl group, 3-oxocyclopentyl group, 4-oxocyclohexyl group, 5-oxo-2-norbornyl group, 8-oxo-3-tricyclodecanyl group, 8-oxo-3- Tetracyclododecanyl group, 4-oxo-1-adamantyl group, cyanomethyl group, 2-cyanoethyl group, 3-cyano-n-propyl group, 4-cyano-n-butyl group, 3-cyano Cyclopentyl group, 4-cyanocyclohexyl group, 5-cyano-2-norbornyl group, 8-cyano-3-tricyclodecanyl group, 8 -Cyano-3-tetracyclododecanyl group, 3-cyano-1-adamantyl group, 2-hydroxy-2,2-di (trifluoromethyl) ethyl group, 3-hydroxy-3,3- Di (trifluoromethyl) -n-propyl group, 4-hydroxy-4,4-di (trifluoromethyl) -n-butyl group, 5- [2-hydroxy-2,2-di (tri Fluoromethyl) ethyl] -2-norbornyl group, 8- [2-hydroxy-2,2-di (trifluoromethyl) ethyl] -3-tricyclodecanyl group, 8- [2-hydroxy- 2,2-di (trifluoromethyl) ethyl] -3-tetracyclododecanyl group, and 3- [2-hydroxy-2,2-di (trifluoromethyl) ethyl] -1-adamantyl Groups are included.

In one embodiment, the proportion of repeating units (1) in resin (A) (eg, of the photoresist composition) is about 10 to about 80 mole percent, more specifically about 20 to about 70 moles of the total content of the repeating units. %, Even more specifically from about 20 to about 60 mol%. The total proportion of the repeating units (2) of the resin (A) (eg of the photoresist composition) is about 20 to about 80 mole percent, more specifically about 20 to about 60 mole percent, even more preferably the total content of the repeating units Is from about 30 to about 60 mole percent. The content of other repeat units described throughout the specification that may be introduced into the resin (A) (eg, of the photoresist composition) is generally about 50 mol% or less, more specifically 30 mol% or less of the total content of the repeat units. .

Resin (A) (eg of photoresist composition) can be prepared by LFRP. The polymerization of the unsaturated monomers is carried out in the presence of a chain transfer agent (CTA) in a suitable solvent and in the presence of a radical polymerization initiator such as hydroperoxide, dialkyl peroxide, diacyl peroxide or azo compound as described throughout the specification. .

The polystyrene-derived weight average molecular weight (hereinafter referred to as "Mw") of the resin (A) as measured by gel permeation chromatography (GPC) is generally about 1,000 to about 100,000, more specifically about 1,000 to about 50,000, even more specifically Is about 2,000 to 30,000, even more specifically about 4,000 to about 12,000.

The ratio (Mw / Mn) of the Mw of the polymer resin (A) (eg of the photoresist composition) to the polystyrene-derived number average molecular weight (hereinafter “Mn”) measured by gel permeation chromatography is generally from about 1 to About 1.8, more specifically about 1 to about 1.5, such as 1.6.

It is preferable that the resin (A) (such as of the photoresist composition) contain little impurities such as halogen or metal. The smaller the amount of such impurities, the better the sensitivity, resolution, process stability, pattern shape, etc. of the polymer resin when used for coating, such as in photoresist, for example. The resin (A) (eg, of the photoresist composition) may be purified using chemical purification methods such as reprecipitation, water washing, liquid-liquid extraction, or a combination of chemical purification methods and physical purification methods such as ultrafiltration or centrifugation. Can be.

The present invention relates to an acrylic or methacrylic polymer resin of a photoresist composition comprising an ester group in which a photosensitive composition for use at a wavelength of less than 248 nm, that is, 193 nm or 157 nm, is stericly bulky, and an acid generator by light It is based at least in part on the finding that it can be formulated by combining. In one aspect, the ester moiety is a monocyclic, bicyclic, tricyclic or tetracyclic non-aromatic ring having 5 or more carbon atoms and further comprising lactone in the cyclic structure. Acid generation by photolysis in the photoresist composition leads to degradation of the ester groups of the polymer resin. This produces polymer carboxylic acids that can be removed by base treatment.

Suitable steric bulky ester groups include those described throughout the specification, and examples include cyclopentane, cyclohexane, adamantane and norbornane. Useful monomers for the synthesis of the polymer resins (eg of photoresist compositions) of the invention react, for example, the corresponding hydroxyl adamantanes or norbornans with methacrylic or acrylic acid, acrylic acid derivatives (such as acyl chloride or acetic anhydride) Can be generated by

Typically, two or more of the monomers are polymerized in a batch process, continuous process, or semicontinuous feed process.

Generally, the polymeric resins of the present invention have a weight average molecular weight (M _W ) of about 2,000 to about 30,000. In certain aspects of the invention, the molecular weight of the polymer resin is about 2,000 to about 20,000, about 3,000 to about 12,000, and about 3,000 to about 8,000.

Another important feature of the novel polymers included in the present invention is their narrow polydispersity. The terms "polydispersity" and "polydispersity index" (PDI) are known in the art and refer to the ratio of weight average molecular weight to number average molecular weight. The polymeric resin of the photoresist composition generally has a PDI value of less than about 2, generally less than about 1.7, in particular from about 1.2 to about 1.4. In some examples, the PDI value is about 1.1 to about 1.2 or less.

Acrylic resins containing acrylic acid esters, methacrylic resins containing methacrylic acid esters, and mixtures thereof having sterically large ester groups are included in the present invention and include, for example, coating applications (e.g. photoresist materials). Useful for

The present invention provides a chemically amplified photosensitive polymer resin. These polymer resins are suitable for use in photoresist systems where excimer laser lithography is used, such as ArF laser lithography, KrF laser lithography and the like. The polymeric resins of the present invention (eg, resins of photoresist compositions) provide excellent properties such as degradation, profile, sensitivity, dry etch resistance, adhesion, and the like when used in photoresists.

The polymerization of the monomers can be carried out according to conventional methods such as bulk polymerization or by semi-continuous polymerization. For example, the polymer resin can be obtained by dissolving a monomer required in an organic solvent and then performing a polymerization reaction in the presence of a polymerization initiator such as an azo compound. The use of chain transfer agents (CTAs) during the polymerization process may be advantageous.

Suitable organic solvents for the polymerization reaction of the present invention are, for example, ketones, ethers, polar aprotic solvents, esters, aromatic solvents and aliphatic hydrocarbons (both linear and branched). Examples of ketones are methyl ethyl ketone (2-butanone) (MEK), acetone and the like. Examples of ethers are alkoxyalkyl ethers such as methoxy methyl ether or ethyl ether, tetrahydrofuran, 1,4-dioxane and the like. Polar aprotic solvents include dimethyl formamide, dimethyl sulfoxide and the like. Suitable esters include alkyl acetates such as ethyl acetate, methyl acetate and the like. Aromatic solvents include alkylaryl solvents such as toluene, xylene and the like and halogenated aromatics such as chlorobenzene. Examples of the hydrocarbon solvent include hexane and cyclohexane.

Polymerization conditions that can be used typically include polymerization temperatures ranging from about 20 ° C. to about 110 ° C., in particular from about 50 ° C. to about 90 ° C., more particularly from about 60 ° C. to about 80 ° C. The atmosphere can be controlled and an inert atmosphere such as nitrogen or argon is advantageous. The molecular weight of the polymer can be controlled by adjusting the ratio of monomers to CTA. In general, the molar ratio of monomer to CTA is in the range of about 5: 1 to about 200: 1, in particular in the range of about 10: 1 to about 100: 1, most particularly in the range of 10: 1 to about 50: 1. .

A free radical source is provided to the polymerization mixture, which may be derived from spontaneous free radical generation upon heating, or in one embodiment from a free radical initiator (radical source generator). In the latter case, the initiator is added to the polymerization mixture at a concentration sufficiently high for acceptable polymerization rates (eg, commercially significant conversions at specific time intervals as listed below). In contrast, too high radical initiator ratios for CTA will provide unwanted dead polymers through radical-radical coupling reactions leading to polymeric materials with uncontrolled properties. The free radical initiator to CTA molar ratio for the polymerization is generally in the range of about 0.5: 1 to about 0.02: 1, for example in the range of 0.2: 1.

As used herein, the term “free radical source” broadly refers to any compound or mixture of compounds that can result in the formation of radical species under suitable operating conditions (thermal activation, irradiation, redox conditions, etc.).

Polymerization conditions also include reaction times, which may range from about 0.5 hours to about 72 hours, in particular from about 1 hour to about 24 hours, in particular from about 2 hours to about 12 hours. The conversion of monomers to polymers is at least about 50%, in particular at least about 75%, more particularly at least about 90%.

The initiator used in the present invention may be a commercial free radical initiator. In general, however, initiators having a short half-life at the polymerization temperature are particularly used. Such initiators are used because the speed of the initiation process can affect the polydispersity index of the resulting polymer. That is, the kinetics of controlled living polymerization is such that fewer polydisperse polymer samples are produced if all chain initiations occur at substantially the same time. In particular, suitable free radical initiators include, for example, alkyl peroxide, substituted alkyl peroxide, aryl peroxide, substituted aryl peroxide, acyl peroxide, alkyl hydroperoxide, substituted alkyl hydroperoxide, aryl hydro Peroxide, substituted aryl hydroperoxide, heteroalkyl peroxide, substituted heteroalkyl peroxide, heteroalkyl hydroperoxide, substituted heteroalkyl hydroperoxide, heteroaryl peroxide, substituted heteroaryl peroxide, heteroaryl Any heat-, redox- including hydroperoxide, substituted heteroaryl hydroperoxide, alkyl perester, substituted alkyl perester, aryl perester, substituted aryl perester, azo compound and halide compound Photoinitiators. Specific initiators include cumene hydroperoxide (CHP), t-butyl hydroperoxide (TBHP), t-butyl perbenzoate (TBPB), sodium carbonate peroxide, benzoyl peroxide (BPO), lauroyl perox Seed (LPO), methylethylketone peroxide 45%, potassium persulfate, ammonium persulfate, 2,2-azobis (2,4-dimethyl-valeronitrile) (VAZO®-65), 1, 1-Azobis (cyclo-hexanecarbonitrile) (VAZO®-40), 2,2-azobis (N, N'-dimethyleneisobutyramidine) dihydrochloride (VAZO®- 044), including 2,2-azobis (2-amidino-propane) dihydrochloride (VAZO®-50) and 2,2-azobis (2-amido-propane) dihydrochloride Any thermal, redox- or photoinitiator. Redox pairs such as persulfate / sulfite and Fe (2 ⁺ ) / peroxide are also useful. In addition, as known in the art, it may also be initiated by heat or UV light, depending on the embodiment to be practiced (e.g., UV light may be used in the modified initiator or RAFT or MADIX techniques discussed herein. have). Those skilled in the art will be able to select appropriate initiators within the scope of the present invention.

Chain transfer agents (CTAs) are known in the art and are used to help control free radical polymerization. Ultimately, a number of different types of CTAs can be introduced at the ends of the polymer as further described below. Examples of suitable CTAs useful in the present invention include US Pat. Nos. 6,512,021, WO 98/01478, WO 99/35177, WO 99/31144, WO 99/05099 and WO 98/58974, each of which is incorporated herein by reference. There are things described in

Further examples include US Pat. Nos. 6,395,850, 6,518,364, and US Patent Application No. 10 / 407,405, entitled "Cleaving and Replacing Thio Control Agent Moieties from," the teachings of which are hereby incorporated by reference in their entirety. Polymers made by Living-Type Free Radical Polymerization, "filed April 3, 2003 (agent control number 2000-089 CIP3) and US Patent Application No. 10 / 104,740 (filed March 22, 2002). .

The use and mechanisms of reversible control agents for free radical polymerization are now generally known and are referred to as RAFT (Reversible Addition Fragmentation Transfer) (eg, each of which is referred to herein). US Pat. No. 6,153,705, WO 98/01478, WO 99/35177, WO 99/31144 and WO 98/58974, which are incorporated herein by reference. Recently, new formulations have been disclosed that are readily available to polymerize desired monomers under commercially acceptable conditions, including the shortest possible reaction times and higher conversions at lower temperatures (e.g., each of which is incorporated herein by reference). US Pat. Nos. 6,380,335, 6,395,850 and 6,518,364.

General CTAs useful in the present invention have the formula:

Wherein R ^x is generally any group that is unstable enough to be released as its free radical form, T is carbon or phosphorus, Z activates a C = S double bond to a reversible free radical addition fragmentation reaction and Any group which may be selected from the group consisting of alkoxy. In another embodiment, Z is through a carbon atom (dithioester) to a C = S bond, through a nitrogen atom (dithiocarbamate), through a sulfur atom (trithiocarbonate) or through an oxygen atom (Dithiocarbonate) is attached. Specific examples for Z can be found in WO 98/01478, WO 99/35177, WO 99/31144 and WO 98/58974, each of which is incorporated herein by reference. In some embodiments, Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof. In particular, Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally substituted heterocyclyl , Optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl.

In particular, suitable CTAs useful in the present invention include those identified in US Pat. No. 6,380,335, the contents of which are incorporated by reference. In particular, the CTA of particular interest in combination with the monomers used throughout the specification may be characterized by the following formula:

In the formula, D is S, Te or Se. In one aspect, D is sulfur. R ⁴ is generally any group that can be readily released under its free radical form (R ⁴ · ) during the addition fragmentation reaction, as shown by Scheme A below (D represents S):

In Scheme A, P · it is a free radical, typically a macro, such as the polymer chain - a radical. In particular, R ⁴ is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl and substituted heteroatom-containing hydrocarbyl and combinations thereof. In particular, R ⁴ is optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted alkoxy, optionally substituted heterocyclyl, optionally substituted alkylthio, optionally substituted amino and optionally substituted polymer chains Selected from the group consisting of: In particular, R ⁴ is —CH ₂ Ph, —CH (CH ₃ ) CO ₂ CH ₂ CH ₃ , —CH (CO ₂ CH ₂ CH ₃ ) ₂ , —C (CH ₃ ) ₂ CN, —CH (Ph ) CN, -C (CH ₃ ) ₂ CO ₂ R (alkyl, aryl, etc.) and -C (CH ₃ ) ₂ Ph.

In addition, R ⁵ and R ⁶ of CTA are each independently from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl and substituted heteroatom-containing hydrocarbyl and combinations thereof Is selected. In particular, R ² and R ³ are each independently hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl , Optionally substituted heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted aryl sulfinyl, and optionally substituted arylphosphonyl. . Of R ⁵ and / or R ⁶ Specific embodiments are listed in the above definitions and also include perfluorinated aromatic rings such as perfluorophenyl. Also, optionally, R ⁵ and R ⁶ may together form a double bond alkenyl moiety away from the nitrogen atom, where R ⁵ and R ⁶ together are an alkenyl moiety optionally substituted.

Finally, R ⁷ of CTA is selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl and substituted heteroatom-containing hydrocarbyl and combinations thereof; Optionally R ⁷ combines with R ⁵ and / or R ⁶ to form a ring structure, wherein the ring has 3 to 50 non-hydrogen atoms. In particular, R ⁷ consists of hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aryl, amino, thio, optionally substituted aryloxy and optionally substituted alkoxy Selected from the group. Particular R ⁴ groups include methyl and phenyl.

The phrase "having a structure" as used herein is not intended to be limiting, and the term "comprising" is used in the same manner as is commonly used. The expression “independently selected from the group consisting of” is used to indicate that the elements listed herein, such as the R groups, may be the same or different (eg, in the structure of Formula 1 ⁵ and R ⁶ may both be substituted with alkyl groups or R ⁵ may be hydrido and R ⁶ may be methyl or the like).

"Any" or "optionally" means that the event or environment mentioned below may or may not occur, and that description includes an example where the event or environment occurs and an example where it does not. For example, the phrase “optionally substituted hydrocarbyl” refers to a hydrocarbyl moiety that may or may not be substituted, and the description includes both unsubstituted hydrocarbyl and hydrocarbyl with substituents.

The term "alkyl" as used herein generally does not necessarily contain 1 to about 24 carbon atoms, but methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, octyl, decyl, and the like. Same branched or unbranched saturated hydrocarbon groups, and cycloalkyl groups such as cyclopentyl, cyclohexyl, and the like are referred to. Generally, but not necessarily, herein, the alkyl group contains 1 to about 12 carbon atoms. The term "lower alkyl" means an alkyl group of 1 to 6 carbon atoms, preferably an alkyl group of 1 to 4 carbon atoms. "Substituted alkyl" refers to alkyl substituted with one or more substituents, and the terms "heteroatom-containing alkyl" and "heteroalkyl" refer to alkyl wherein one or more carbon atoms is replaced by a heteroatom.

The term "alkenyl" as used herein does not necessarily contain from 2 to about 24 carbon atoms and at least one double bond, but includes ethenyl, n-propenyl, isopropenyl, n-butenyl, isobutenyl, Branched or unbranched hydrocarbon groups, such as octenyl, decenyl, and the like. Generally, but not necessarily, alkenyl groups herein contain 2 to about 12 carbon atoms. The term "lower alkenyl" refers to alkenyl groups of 2 to 6, preferably 2 to 4 carbon atoms. "Substituted alkenyl" refers to alkenyl substituted with one or more substituents, and the terms "heteroatom-containing alkenyl" and "heteroalkenyl" refer to alkenyl in which one or more carbon atoms is replaced with a heteroatom.

As used herein, the term "alkynyl" does not necessarily contain from 2 to about 24 carbon atoms and at least one triple bond, but ethynyl, n-propynyl, isopropynyl, n-butynyl, isobutynyl Branched or unbranched hydrocarbon groups such as octynyl, decinyl, and the like. Although generally not necessary, alkynyl groups herein contain 2 to about 12 carbon atoms. The term "lower alkynyl" refers to an alkynyl group of 2 to 6, preferably 3 or 4 carbon atoms. "Substituted alkynyl" refers to alkynyl substituted with one or more substituents, and the terms "heteroatom-containing alkynyl" and "heteroalkynyl" refer to alkynyl in which one or more carbon atoms is replaced with a heteroatom.

The term "alkoxy" as used herein refers to an alkyl group bonded through a single terminated ether linking group. That is, an "alkoxy" group may be represented as -O-alkyl when alkyl is as defined above. "Lower alkoxy" group refers to an alkoxy group containing 1 to 6, preferably 1 to 4 carbon atoms. The term "aryloxy" is used in the same manner as for aryl as defined below.

Likewise, the term "alkyl thio" as used herein refers to an alkyl group bonded through a single terminated thio ether linker. That is, an "alkyl thio" group can be represented by -S-alkyl when the alkyl group is as defined above. "Lower alkyl thio" groups refer to alkyl thio groups containing 1 to 6, preferably 1 to 4 carbon atoms.

As used herein, the term "alenyl" refers to a molecular fragment having the structural formula -CH = C = CH2 in a conventional sense. "Allenyl" groups may or may not be substituted with one or more non-hydrogen substituents.

As used herein, unless otherwise specified, the term "aryl" refers to an aromatic substituent containing a single aromatic ring or multiple aromatic rings that are fused together, covalently linked, or bonded together to a conventional group, such as a methylene or ethylene moiety. Conventional linking groups may also be carbonyl of benzophenone, oxygen atom of diphenylether, or nitrogen atom of diphenylamine. Preferred aryl groups contain, for example, one aromatic ring or two conjugated or linked aromatic rings, such as phenyl, naphthyl, biphenyl, diphenylether, diphenylamine, benzophenone. In certain embodiments, the aryl substituent has 1 to about 200 carbon atoms, typically 1 to about 50 carbon atoms, preferably 1 to about 20 carbon atoms. "Substituted aryl" refers to an aryl moiety substituted with one or more substituents (eg, tolyl, mesityl and perfluorophenyl), and the terms "heteroatom-containing aryl" and "heteroaryl" It refers to aryl in which a carbon atom is replaced with a heteroatom.

The term "aralkyl" refers to an alkyl group having an aryl substituent, and the term "aralkylene" refers to an alkylene group having an aryl substituent. The term "alkaryl" refers to an aryl group having an alkyl substituent, and the term "alk arylene" refers to an arylene group having an alkyl substituent.

The terms "halo" and "halogen" are used in the conventional sense to refer to chloro, bromo, fluoro or iodo substituents. The terms "haloalkyl", "haloalkenyl" or "haloalkynyl" (or "halogenated alkyl", "halogenated alkenyl" or "halogenated alkynyl") each represent one or more of the hydrogen atoms of the group as halogen atoms. Refers to substituted alkyl, alkenyl or alkynyl groups.

The term “heteroatom-containing” as in “heteroatom-containing hydrocarbyl group” refers to a molecule or molecular fragment in which one or more carbon atoms have been replaced by atoms other than carbon atoms, eg, nitrogen, oxygen, sulfur, phosphorus, or silicon Say Likewise, the term "heteroalkyl" refers to heteroatom-containing alkyl substituents, the term "heterocyclic" refers to heteroatom containing cyclic substituents, and the term "heteroaryl" refers to aryl substituents containing heteroatoms. When the term "heteroatom-containing" appears before a heteroatom-containing group, it is intended that the term apply to all members of the group. That is, the phrase "heteroatom-containing alkyl, alkenyl and alkynyl" should be interpreted as "heteroatom-containing alkyl, heteroatom-containing alkenyl and heteroatom-containing alkynyl".

"Hydrocarbyl" means from 1 to about 30 carbon atoms, preferably from 1 to about 24 carbon atoms, most preferably from 1 to about 12 carbon atoms, such as alkyl groups, alkenyl groups, aryl groups, etc. Monovalent hydrocarbyl radicals containing branched, saturated or unsaturated species). The term "lower hydrocarbyl" refers to hydrocarbyl of 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms. "Substituted hydrocarbyl" refers to hydrocarbyl substituted with one or more substituents, and the terms "heteroatom-containing hydrocarbyl" and "heterohydrocarbyl" refer to hydrocarby with one or more carbon atoms replaced by heteroatoms. Says Bill.

"Substituted", such as in "substituted hydrocarbyl", "substituted aryl", "substituted alkyl", "substituted alkenyl", and the like, refers to hydrocarbyl, hydro, as inferred by some of the foregoing definitions. In carbylene, alkyl, alkenyl, or other moieties, one or more hydrogen atoms bonded to carbon atoms are substituted with one or more substituents, such as hydroxyl, alkoxy, thio, phosphino, amino, halo, silyl, and the like. When the term "substituted" appears before the list of substitutable groups, it is intended that the term apply to all members of the group. That is, the phrase "substituted alkyl, alkenyl and alkynyl" should be interpreted as "substituted alkyl, substituted alkenyl and substituted alkynyl". Likewise, "optionally substituted alkyl, alkenyl and alkynyl" should be interpreted as "optionally substituted alkyl, optionally substituted alkenyl and optionally substituted alkynyl".

As used herein, the term "silyl" refers to a -SiZ1Z2Z3 radical, wherein each Z1, Z2 and Z3 are independently hydrido and optionally substituted alkyl, alkenyl, alkynyl, aryl, aralkyl, alkaryl , Heterocyclic, alkoxy, aryloxy and amino.

The term "phosphino" as used herein refers to the group -PZ1Z2, wherein each Z1 and Z2 are independently hydrido and optionally substituted alkyl, alkenyl, alkynyl, aryl, aralkyl, alkaryl, hetero It is selected from the group consisting of cyclic and amino.

The term "amino" is used herein to refer to the group -NZ1Z2, wherein each Z1 and Z2 is independently a hydrido and optionally substituted alkyl, alkenyl, alkynyl, aryl, alkaryl and heterocyclic Selected from the group consisting of:

The term "thio" is used herein to refer to the group -SZ1, wherein Z1 is from the group consisting of hydrido and optionally substituted alkyl, alkenyl, alkynyl, aryl, aralkyl, alkaryl and heterocyclic Is selected.

All references to elements and groups in the Periodic Table of Elements used herein relate to a version of the table published by the Handbook of Chemistry and Physics, CRC Press, 1995, in which a new IUPAC system for counting groups is disclosed.

In certain embodiments, R ⁷ combines with either R ⁵ or R ⁶ to form a substituted or unsubstituted pyrazole moiety. As an example CTA, for example

There is this.

In some embodiments, the resulting polymer (eg, the polymer of the photoresist composition) will have one or more termini, for example with a thi group (from CTA). Depending on the application intended for the polymer, the thio group may be undesirable. Accordingly, the present invention also provides a polymer resin in which the CTA is removed from the polymer resin end.

In certain embodiments described throughout this specification, the resulting polymer is at the terminal end, the end of which is at the end of the main chain, star arm, comb end, branch end or at the end of the graft. However, it contains a CTA moiety (part of the CTA, such as a dithio carbonyl moiety). Removal of the CTA can be performed by several methods below. Mechanically, free radical chain transfer reactions are believed to separate residues, such as dithio CTA moieties, from the polymer end point by the addition of an external radical source.

In one embodiment, in some instances it is possible to separate the CTA moiety (eg, thiocarbonylthio moiety, thio) from the polymer end to remove at least sulfur containing portions of the CTA from the polymer end endpoint (if present). Is advantageous in In one embodiment, this can be done by radical reduction of the dithiophosphoryl group or dithiocarbonyl group using a compound having a labile hydrogen atom and a free radical initiator. The process essentially removes unwanted groups from the polymer chain endpoints and replaces them with hydrogen atoms. See, for example, WO 02/090397, which is incorporated herein by reference in its entirety.

In another aspect, CTA can be replaced by the use of an excess of initiator, whereby fragmentation products of the initiator are described in US patent application Ser. No. 10 / 407,405, the disclosure of which is incorporated herein by reference in its entirety. Replace CTA at the end of the polymer as described in the name "Cleaving and Replacing Thio Control Agent Moieties from Polymers made by Living-Type Free Radical Polymerization", filed Apr. 3, 2003 (Agent Control Number 2000-089CIP3).

In another aspect, CTA is disclosed in US Patent Application No. 10 / 407,405, entitled "Cleaving and Replacing Thio Control Agent Moieties from Polymers made by Living-Type Free Radical Polymerization, the teachings of which are incorporated herein by reference in their entirety. ", May be replaced by the use of an initiator combined with a RAFT agent as described in the April 3, 2003 application (Agent Reg. No. 2000-089CIP3).

In another aspect, CTA is disclosed in US Patent Application No. 10 / 609,225, entitled "Removal of the Thiocarbonythio or Thiophosphorylthio End Group of Polymers and Further Functionalization Thereof", the teachings of which are incorporated herein by reference in their entirety. It may be replaced by a non-monopolymerizable monomer introduced with a radical source as described in the application June 26, 2003 (Agent Control Number 2003-042).

While not wishing to be bound by any theory, it is believed that the separation of the thio group from the polymer proceeds through a series of reactions described in Schemes 1 and 2:

I ₂ → 2I ·

PST (= S) -Z + I · → P · + IS = T (= S) -Z

Wherein P represents a polymer, T is carbon or phosphorus, S is sulfur, I ₂ is a free radical source, I · is a free radical derived from I ₂ decomposition, and Z is as defined above. Scheme 1 represents the activation of the free radical initiator I · of a radical, Scheme 2 dithio generating a polymer radical P · - shows the fragmentation-addition of I · on the terminated polymer.

In some embodiments, the external radical source is a conventional radical initiator, such as any of the above initiators. Regardless of its exact nature, the free radical source carried out in the procedure according to the invention is used under cleavage reaction conditions which allow the production of free radicals, which in one embodiment is via thermal activation, ie the temperature of the reaction medium. Is usually carried out by raising it from about room temperature (about 20 ° C.) to about 200 ° C., in particular from about 40 ° C. to about 180 ° C., in particular from about 50 ° C. to about 120 ° C. In other embodiments, free radicals are generated through light activation. It includes free radical sources that can be activated by UV light such as benzoin ether and benzophenone. High energy irradiation such as gamma rays and electron beams is also known to generate radicals.

The free radical source used can be introduced into the reaction medium in one single increment. However, this may also be introduced gradually, in parts or in succession.

Cleavage reaction conditions that can be used include conditions such as temperature, pressure, atmosphere, reaction time and proportion of reaction components. Useful temperatures range from about room temperature (about 20 ° C.) to about 200 ° C., in particular from about 40 ° C. to about 180 ° C., in particular from about 50 ° C. to about 120 ° C. In some embodiments, the atmosphere can be controlled using an inert atmosphere such as nitrogen or argon. In other embodiments, an ambient atmosphere is used. Cleavage reaction conditions also include open and closed atmospheres and pressures at ambient conditions. In embodiments where the cleavage reaction is conducted in a closed atmosphere, the temperature is higher than room temperature and the pressure may rise as a result of any heated solvent. In some embodiments, light control is also desirable. In particular, the reaction can be carried out under visible or UV light.

The amount of free radical source varies depending on its efficiency, the manner in which the source is introduced, and the desired end product. The free radical source employed has an amount of free radicals that can be released by the source relative to the total molar amount of the groups of the polymer in which separation is desired, from about 1% to about 800% (molar ratio), in particular from about 50% to about 400 % (Molar ratio), and especially from about 100% to about 300% (molar ratio), in particular from about 200 to about 300%. In some embodiments, complete removal or as near as possible complete removal is desired, and in such embodiments, excess free radical sources are introduced.

Excess free radical sources are intended to compensate for known side reactions in free radical processes (e.g., Scheme 5) as well as possible free radical losses caused by the basket effect. If available, a free radical source efficiency factor f, defined as the ratio of active radicals to the total radicals generated upon free radical circle decomposition, can be used to control the concentration of I ₂ .

Most known free radical sources can be used as long as their half-life (defined as the time at which half of the free radical source is consumed) is approximately 10 minutes to 20 hours.

Typical initiators that can be used as free radical sources include alkyl peroxides, substituted alkyl peroxides, aryl peroxides, substituted aryl peroxides, acyl peroxides, alkyl hydroperoxides, substituted alkyl hydroperoxides, aryl hydroperoxides Substituted aryl hydroperoxide, heteroalkyl peroxide, substituted heteroalkyl peroxide, heteroalkyl hydroperoxide, substituted heteroalkyl hydroperoxide, heteroaryl peroxide, substituted heteroaryl peroxide, heteroaryl hydroperox Selected from seed, substituted heteroaryl hydroperoxides, alkyl peresters, substituted alkyl peresters, aryl peresters, substituted aryl peresters, dialkylperdicarbonates, inorganic peroxides, hypotrit and azo compounds do. Particular initiators include lauroyl and benzoyl peroxide (BPO) and AIBN. Some azo compounds are 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (4-methoxy-2,4-dimethyl valeronitrile), dimethyl 2,2'- Azobis (2-methylpropionate), 1-[(cyano-1-methylethyl) azo] formamide, 2,2'-azobis (N-cyclohexyl-2-methylpropionamide), 2, 2'-azobis (2,4-dimethyl valeronitrile), 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis [N- (2-propenyl) -2 -Methylpropionamide], 2,2'-azobis (N-butyl-2-methylpropionamide), 2,2'-azobis [2- (5-methyl-2-imidazolin-2-yl) Propane] dihydrochloride, 2,2'-azobis [2- (2-imidazolin-2-yl) propane disulfate dihydrate, 2,2'-azobis [N- (2-carboxyethyl)- 2-methylpropionamidine] tetrahydrate, 2,2'-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propane} dihydrochloride, 2, 2'-azobis {2-methyl-N [1,1-bis (hydroxy) Methyl) -2-hydroxyethyl] propionamide, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis [2- (2- Imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis (2-methylpropionamide) dihydrochloride, 2,2'-azobis [2- (3,4,5,6 -Tetrahydropyrimidin-2-yl) propane] dihydrochloride, 2,2'-azobis [2- (2-imidazolin-2-yl) propane], and 2,2'-azobis {2 -Methyl-N- [2- (1-hydroxybutyl)] propionamide}. This includes initiators that can be activated by UV such as benzoin ether and benzophenone. Other initiators can be activated by high energy such as gamma rays and electron beams. The half life can be adjusted by setting the reaction temperature in the required range. The latter is determined by the temperature dependence of the initiator degradation rate (available via the supplier information package or in [The Chemistry of Free Radical Polymerization, G.Moad, DH Salomon, Eds. Pergamon Pub. 1995]). The rate of decomposition and thus radical production can also be controlled by the addition of a reducing agent (especially when the initiator has oxidant properties), for example metabisulfite, ascorbic acid, sulfite-formaldehyde adducts, amines and Low oxidation metals and the like can be used with initiators in the form of peroxides to accelerate the radical flux.

Cleavage reaction conditions also include reaction times, which may range from about 0.5 hours to about 72 hours, in particular from about 1 hour to about 24 hours, in particular from about 2 hours to about 12 hours. From the polymer, for example, the separation of the tea group is at least about 50%, in particular at least about 75%, in particular at least about 85%, in particular at least about 95%. The substitution of the thio group is at least about 50%, in particular at least about 75%, in particular at least about 85%, in particular at least about 95%.

Various RAFT agents and the like can be used to replace the thio group with a variety of different moieties as described above. In one embodiment, as described in WO 02/090397 (transferred to Rhodia Chimie), the thio portion of the CTA may be replaced by a hydrogen atom. In another embodiment, the thio group may be replaced by non-monopolymerizable monomer units. In another embodiment, only one free radical source is introduced to cap the polymer end.

The cleavage reaction mixture may employ a reaction medium that is generally a solvent. Cleavage reaction conditions also include stirring or refluxing the reaction medium. The resulting polymer radical P · may then be capped in one of three ways as shown in Schemes 3, 4 and 5:

P · + I · → PI

_{P · + I 2 → PI +} I ·

P · + P · → Coupling Product

Scheme 3 shows the radical coupling of the polymer radicals generated in Scheme 2 with the free radicals generated in Scheme 1, resulting in capped polymer P-I. Scheme 4 shows the transfer reaction between the polymer radical generated in Scheme 2 and the free radical initiator providing a separate polymer and a new free radical source. Scheme 5 shows the coupling reaction between two polymer radicals.

In one embodiment, Schemes 3 and 4 are preferred reactions. Scheme 5 is a side reaction that contributes to increasing the molecular weight of the bulk polymer sample and broadening the molecular weight distribution. It has been found that the cleavage reaction conditions lead to quantitative separation of the dithio compound, for example with little change in molecular weight properties (M _W and polydispersity index).

In one embodiment, the polymer is treated with a free radical source, such as an initiator, under cleavage reaction conditions to facilitate Schemes 3 and 4. These conditions range from about 200% to about 500% (molar ratio), in particular from about 200% to about 300 (molar ratio) relative to the total molar amount of groups of the polymer where the amount of free radicals that can be released by the source is preferred for separation. Introducing a radical source in an amount such that:

The resulting polymer has new groups at its ends that make the polymer more desirable for certain applications. For example, the polymer may be more desirable for applications that cannot tolerate the presence of sulfur in amounts present in the polymer prior to modification, such as home or personal use products where odor may be present in question.

It is advantageous that the reaction product with or without the CTA end group is purified after completion of the polymerization reaction, by reprecipitation or the like. Typical precipitants include low molecular weight alcohols such as isopropyl, methyl, ethyl and butyl alcohol.

In one aspect, the invention is a photoresist polymer composition comprising a photo-acid generator that generates an acid upon exposure to an energy source (hereinafter referred to as "photo-acid generator (B)"). ).

The photo-acid generator (B) causes the acid-degradable groups in the resin (A) to be separated by the acid generated upon exposure. As a result, the exposed area of the resist film is easily dissolved in the alkali developer, whereby a positive-tone resist pattern is formed.

Useful photo-acid generators (B) of the present invention include compounds represented by the following formula (5):

Wherein R ¹³ is a hydrogen atom, a hydroxyl group, a linear or branched alkyl group having 1-10 carbon atoms, a linear or branched alkoxyl group having 1-10 carbon atoms, or 2-11 carbon atoms A linear or branched alkoxycarbonyl group, R ¹⁴ is a hydrogen atom or a linear or branched alkyl group having 1-10 carbon atoms, p is an integer from 0-3, and R ¹⁵ is each independently 1-10 carbons A linear or branched alkyl group having an atom, a phenyl group or a naphthyl group which may have one or more substituents, or two R ¹⁵ groups together form a substituted or unsubstituted divalent group having 2-10 carbon atoms and , q is an integer of 0-2, Z ^- represents an anion, for example, an anion having a structure of C _a F _{2a + 1} SO _3- where a is an integer of 1-10.

Examples of linear or branched alkyl groups having about 1 to about 10 carbon atoms, represented by R ¹³ , R ¹⁴ or R ¹⁵ in formula (5) include methyl, ethyl, n-propyl, i-propyl, n-butyl group, 2-methylpropyl group, 1-methylpropyl group, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethylhex The actual group, n-nonyl group, and n-decyl group are mentioned.

Examples of linear or branched alkoxyl groups having about 1 to about 10 carbon atoms, represented by R ¹³ in formula (5), include methoxy, ethoxy, n-propoxy, i-propoxy, n -Butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group, n-pentyloxy group, neopentyloxy group, n-hexyloxy group, n-heptyloxy group, n-octyl octa The period, 2-ethylhexyloxy group, n-nonyloxy group, and n-decyloxy group are included.

Examples of linear or branched alkoxycarbonyl groups having about 2 to about 11 carbon atoms represented by R ¹³ in formula (5) include methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, i-propoxycarbonyl group , n-butoxycarbonyl group, 2-methylpropoxycarbonyl group, 1-methylpropoxycarbonyl group, t-butoxycarbonyl group, n-pentyloxycarbonyl group, neopentyloxycarbonyl group, n-hexyloxycarbonyl group, n-heptyloxycarbonyl group, n-octyloxycarbonyl group, 2-ethylhexyloxycarbonyl group, n-nonyloxycarbonyl group, and n-decyloxycarbonyl group are contained.

Specific groups of R ¹³ in the formula (5) include a hydrogen atom, a hydroxyl group, a methoxy group, an ethoxy group, an n-butoxy group and the like.

In the formula (5), mention may be made in particular of hydrogen atoms and methyl groups as R ¹⁴ groups.

In certain embodiments p is 0 or 1.

Examples of substituted or unsubstituted phenyl groups represented by R ¹⁵ in formula (5) may be substituted with phenyl groups or one or more linear, branched, or cyclic alkyl groups having from about 1 to about 10 carbon atoms. Alkyl-substituted phenyl groups such as o-tolyl group, m-tolyl group, p-tolyl group, 2,3-dimethylphenyl group, 2,4-dimethylphenyl group, 2,5-dimethylphenyl group, 2,6-dimethyl Phenyl group, 3,4-dimethylphenyl group, 3,5-dimethylphenyl group, 2,4,6-trimethylphenyl group, and 4-ethylphenyl group; Groups obtained by substituting a phenyl group or an alkyl-substituted phenyl group with one or more groups (e.g., hydroxyl groups, carboxyl groups, cyano groups, nitro groups, alkoxyl groups, alkoxyalkyl groups, alkoxycarbonyl groups, and alkoxycarbonyloxy groups) Can be mentioned.

Examples of alkoxyl groups that may be substituents of a phenyl group or an alkyl-substituted phenyl group include linear, branched, or cyclic alkoxyl groups having about 1 to about 20 carbon atoms, for example methoxy, ethoxy, n- Propoxy group, i-propoxy group, n-butoxy group, 2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group, a cyclopentyloxy group, and a cyclohexyloxy group are mentioned.

Examples of alkoxyalkyl groups, linear, branched, or cyclic alkoxyalkyl groups having about 2 to about 21 carbon atoms include methoxymethyl group, ethoxymethyl group, 1-methoxyethyl group, 2-methoxyethyl group, 1-ethoxy Ethyl group and 2-ethoxyethyl group are mentioned.

Examples of alkoxycarbonyl groups include linear, branched, or cyclic alkoxycarbonyl groups having about 2 to about 21 carbon atoms, such as methoxycarbonyl group, ethoxycarbonyl group, n-propoxycarbonyl group, i-propoxycarbonyl group, n -Butoxycarbonyl group, 2-methylpropoxycarbonyl group, 1-methylpropoxycarbonyl group, t-butoxycarbonyl group, cyclopentyloxycarbonyl group, and cyclohexyloxycarbonyl group are mentioned.

Examples of alkoxycarbonyloxy groups include linear, branched, or cyclic alkoxycarbonyloxy groups having about 2 to about 21 carbon atoms, for example methoxycarbonyloxy groups, ethoxycarbonyloxy groups, n -Propoxycarbonyloxy group, i-propoxycarbonyloxy group, n-butoxycarbonyloxy group, t-butoxycarbonyloxy group, and cyclopentyloxycarbonyl group, and cyclohexyloxycarbonyl group are included.

Examples of substituted or unsubstituted naphthyl groups represented by R ¹⁵ include naphthyl groups obtained by substituting a hydrogen atom in a naphthyl group and a naphthyl group with a linear, branched, or cyclic alkyl group having about 1 to about 10 carbon atoms. Derivatives such as 1-naphthyl group, 2-methyl-1-naphthyl group, 3-methyl-1-naphthyl group, 4-methyl-1-naphthyl group, 4-methyl-1-naphthyl group, 5-methyl- 1-naphthyl group, 6-methyl-1-naphthyl group, 7-methyl-1-naphthyl group, 8-methyl-1-naphthyl group, 2,3-dimethyl-1-naphthyl group, 2,4-dimethyl-1 -Naphthyl group, 2,5-dimethyl-1-naphthyl group, 2,6-dimethyl-1-naphthyl group, 2,7-dimethyl-1-naphthyl group, 2,8-dimethyl-1-naphthyl group, 3, 4-dimethyl-1-naphthyl group, 3,5-dimethyl-1-naphthyl group, 3,6-dimethyl-1-naphthyl group, 3,7-dimethyl-1-naphthyl group, 3,8-dimethyl-1- Naphthyl group, 4,5-dimethyl-1-naphthyl group, 5,8-dimethyl-1-naphthyl group, 4-ethyl-1-naphthyl group, 2-naphthyl group, 1-methyl-2-naphthyl group, 3- Methyl-2-naphthyl group, and 4- One or more hydrogen atoms in the butyl-2-naphthyl group and the naphthyl group or the alkyl-substituted naphthyl group are hydroxyl, carboxyl, cyano, nitro, alkoxyl, alkoxyalkyl, alkoxycarbonyl, or alkoxycarbonyloxy And groups obtained by further substitution.

Examples of the alkoxyl group, alkoxyalkyl group, alkoxycarbonyl group, and alkoxycarbonyloxy group substituted with a naphthyl group or an alkyl-substituted naphthyl group include the groups mentioned in the phenyl group and the alkyl-substituted phenyl group.

A divalent group having about 2 to about 10 carbon atoms is formed by two R ¹⁵ groups, which may be a group which forms together with a sulfur atom in the formula a 5- or 6-membered cyclic structure, in particular a 5-membered cyclic structure. It may be a group to form (especially tetrahydrothiophene cyclic structure).

Examples of suitable substituents for the divalent groups mentioned above include those mentioned as suitable substituents of phenyl groups and alkyl-substituted phenyl groups, for example hydroxyl groups, carboxyl groups, cyano groups, nitro groups, alkoxyl groups, alkoxyalkyl groups, alkoxycarbonyl groups, And alkoxycarbonyloxy groups.

In particular, R ¹⁵ in formula (5) may be a methyl group, an ethyl group, or a phenyl group. A divalent group having a tetrahydrothiophene cyclic structure formed from two R ¹⁵ groups contains a sulfur atom.

"Q" in formula (5) may be 0 or 1.

The C _a F _{2a + 1} group of F _{2a + 1} SO ₃ ^- represented by Z ⁻ in formula (5) is _a perfluoroalkyl group having “a” carbon atoms, which may be linear or branched.

"a" may be from about 4 to about 8.

Specific examples of acid generators (5) include

Triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, 1-naphthyldimethylsulfonium trifluoromethane Sulfonate, 1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate, 1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate, 1-naphthyldiethylsulfonium trifluoromethanesulfonate , 1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate, 1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate, 4-hydroxy-1-naphthyldimethylsulfonium trifluoro Methanesulfonate, 4-hydroxy-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate, 4-hydroxy-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate, 4- Hydroxy-1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4-hydroxy-1-naphthyldi Ethylsulfonium nonafluoro-n-butanesulfonate, 4-hydroxy-1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate, 4-cyano-1-naphthyldimethylsulfonium trifluoro Methanesulfonate, 4-cyano-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate, 4-cyano-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate, 4- Cyano-1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4-cyano-1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate, 4-cyano-1-naphthyldiethylsulfonate Phosphium perfluoro-n-octanesulfonate, 4-nitro-1-naphthyldimethylsulfonium trifluoromethanesulfonate, 4-nitro-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate, 4-nitro-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate, 4-nitro-1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4-nitro-1- Fethyldiethylsulfonium nonafluoro-n-butanesulfonate, 4-nitro-1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate, 4-methyl-1-naphthyldimethylsulfonium trifluoro Methanesulfonate, 4-methyl-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate, 4-methyl-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate, 4-methyl- 1-naphthyldiethylsulfonium trifluoromethanesulfonate, 4-methyl-1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate, 4-methyl-1-naphthyldiethylsulfonium perfluoro- n-octanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydro Thiophenium nonafluoro-n-butanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-n- Butoxy Nyl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-butoxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-n-butoxyphenyl Tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-hydroxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-hydroxynaphthalene- 1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-hydroxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- ( 4-methoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-methoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-methoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-ethoxynaphthalen-1-yl) tetrahydroti Ophenium trifluoromethanesulfonate, 1- (4-ethoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-ethoxynaphthalen-1-yl) Tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-part Methoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfo Nate, 1- (4-methoxymethoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-methoxymethoxynaphthalen-1-yl) tetrahydrothiophenium nona Fluoro-n-butanesulfonate, 1- (4-methoxymethoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4-ethoxymethoxynaphthalene- 1 day) Tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-ethoxymethoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-ethoxymeth Methoxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- [4- (1-methoxyethoxy) naphthalen-1-yl] -tetrahydrothiophenium trifluoro Methanesulfonate, 1- [4- (1-methoxyethoxy) naphthalen-1-yl] tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- [4- (1-methoxyethoxy ) Naphthalen-1-yl] tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- [4- (2-methoxyethoxy) naphthalen-1-yl] -tetrahydrothiophenium trifluoro Methanesulfonate, 1- [4- (2-methoxyethoxy) naphthalen-1-yl] tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- [4- (2-methoxyethoxy ) Naphthalen-1-yl] tetrahydroti Phenium perfluoro-n-octanesulfonate, 1- (4-methoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-methoxycarbonyloxy Naphthalen-1-yl) -tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-methoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium perfluoro-n- Octanesulfonate, 1- (4-ethoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-ethoxycarbonyloxynaphthalen-1-yl) tetra Hydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-ethoxycarbonyloxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (4- n-propoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-propoxycarbonyloxynaphthalene-1 -Yl) -tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-n-propoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium perfluoro-n-octane Sulfonate, 1- (4-i-propoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-i-propoxycarbonyloxynaphthalene-1- Yl) -tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-i-propoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium perfluoro-n-octanesulfo Nate, 1- (4-n-butoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-n-butoxycarbonyloxynaphthalen-1-yl ) -Tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-n-butoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium perfluoro-n-octanesulfonei , 1- (4-t-butoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-t-butoxycarbonyloxynaphthalen-1-yl ) -Tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-t-butoxycarbonyloxynaphthalen-1-yl) -tetrahydrothiophenium perfluoro-n-octanesulfonate , 1- (4-benzyloxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethanesulfonate, 1- (4-benzyloxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n- Butanesulfonate, 1- (4-benzyloxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (2-naphthalen-1-yl-2-oxoethyl) Tetrahydrothiophenium trifluoromethanesulfonate, 1- (2-naphthalen-1-yl-2-oxoethyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, and 1- (2-naphthalene -1-yl-2-oxo Butyl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- [4- (2-tetrahydrofuranyloxy) naphthalen-1-yl] -tetrahydrothiophenium trifluoromethanesulfonate, 1- [4- (1-tetrahydrofuranyloxy) naphthalen-1-yl] -tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- [4- (2-tetrahydrofuranyloxy) Naphthalen-1-yl] -tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- [4- (2-tetrahydropyranyloxy) naphthalen-1-yl] tetrahydrothiophenium trifluoro Methanesulfonate, 1- [4- (2-tetrahydropyranyloxy) naphthalen-1-yl] -tetrahydrothiophenium nonafluoro-n-butanesulfonate, and 1- [4- (2-tetra Hydropyranyloxy) naphthalen-1-yl] -tetrahydrothiophenium perfluoro-n-octanesulfonate.

In particular, the photo-acid generator (5) is triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, 1- (3,5-dimethyl-4- Hydroxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium perfluoro-n-octanesulfonate, 1 -(4-hydroxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-hydroxynaphthalen-1-yl) tetrahydrothiophenium perfluoro-n -Octanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-n-butoxy cinaphthalen-1-yl) Tetrahydrothiophenium perfluoro-n-octanesulfonate, 1- (2-naphthalen-1-yl-2-oxoethyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (2 Naphthalen-1-yl-2-oxoethyl) te Trahydrothiophenium perfluoro-n-octanesulfonate, and the like.

Examples of acid generators other than the acid generator having the formula (5) (hereinafter referred to as "other acid generators") include onium salt compounds, halogen-containing compounds, diazoketone compounds, sulfone compounds, sulfonate compounds, and the like. Included.

Examples of other acid generators are as follows.

Onium Salts:

Examples of onium salts include iodonium salts, sulfonium salts, phosphonium salt salts, diazonium salts, and pyridinium salts.

Specific examples of onium salts include diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, bis (4 -t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium Perfluoro-n-octanesulfonate, cyclohexyl 2-oxocyclohexyl methylsulfonium trifluoromethanesulfonate, dicyclohexyl 2-oxocyclohexylsulfonium trifluoromethanesulfonate, and 2- Oxocyclohexyldimethylsulfonium trifluoromethanesulfonate.

Halogen containing compound:

Examples of the halogen-containing compound include a haloalkyl group-containing hydrocarbon compound and a haloalkyl group-containing heterocyclic compound.

Specific examples of the halogen-containing compound include (trichloromethyl) -s-triazine derivatives such as phenylbis (trichloromethyl) -s-triazine, 4-methoxyphenylbis (trichloromethyl) -s-tri Azine, and 1-naphthylbis (trichloromethyl) -s-triazine, and 1,1-bis (4-chlorophenyl) -2,2,2-trichloroethane.

Diazoketone Compounds:

Examples of diazoketone compounds include 1,3-diketo-2-diazo compounds, diazobenzoquinone compounds, and diazonaptoquinone compounds.

Examples of diazoketone compounds include 1,2-naphthoquinone diazido-4-sulfonyl chloride, 1,2-naphthoquinone diazido-5-sulfonyl chloride, 1,2-naphthoquinone diazido-4 Sulfonates or 1,2-naphthoquinonediazido-5-sulfonates of 2,3,4,4'-tetrahydroxybenzophenone, and 1,1,1-tris (4-hydroxyphenyl) ethane 1,2-naphthoquinone diazido-4-sulfonate and 1,2-naphthoquinone diazido-5-sulfonate.

Sulfone compounds:

Examples of sulfone compounds include ketosulfones, sulfonylsulfones, and diazo compounds of these compounds.

Specific examples of the sulfone compound include 4-trisfenacyl sulfone, mesitylphenacyl sulfone, bis (phenylsulfonyl) methane and the like.

Sulfonate Compounds:

Examples of sulfonate compounds include alkyl sulfonates, alkylimide sulfonates, haloalkyl sulfonates, aryl sulfonates, and imino sulfonates.

Specific examples of the sulfone compound include benzointosylate, tris (trifluoromethanesulfonate) of pyrogallol, nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate, trifluoromethanesulfonylbicyclo [2.2 .1] hept-5-ene-2,3-dicarboxyimide, nonafluoro-n-butanesulfonylbicyclo [2.2.1] -hept-5-ene-2,3-dicarboxyimide, perfluor Rho-n-octanesulfonylbicyclo [2.2.1] -hept-5-ene-2,3-dicarboxyimide, N-hydroxysuccinimidetrifluoromethanesulfonate, N-hydroxysuccinimide Nonafluoro-n-butanesulfonate, N-hydroxysuccinimideperfluoro-n-octanesulfonate, 1,8-naphthalenedicarboxylic acid imide trifluoromethanesulfonate, 1,8-naphthalene Dicarboxylic acid imide nonafluoro-n-butanesulfonate, and 1,8-naphthalenedicarboxylic acid imide perfluoro-n-octanesulfonate The.

Of these acid generators, the following compounds are of particular importance: diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n Octanesulfonate, bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4- t-butylphenyl) iodonium perfluoro-n-octanesulfonate, cyclohexyl 2-oxocyclohexyl methylsulfonium trifluoromethanesulfonate, dicyclohexyl 2-oxocyclohexylsulfonium trifluor Romethanesulfonate, 2-oxocyclohexyldimethylsulfonium trifluoromethanesulfonate, trifluoromethanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, nonafluoro -n-butanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxy Siimide, perfluoro-n-octanesulfonylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N-hydroxysuccinimido trifluoromethanesulfonate, N-hydride Oxysuccinimido nonafluoro-n-butanesulfonate, N-hydroxysuccinimido perfluoro-n-octanesulfonate, and 1,8-naphthalenedicarboxylic acid imide trifluoromethanesulfonate.

In the photoresist composition, the acid generator (B) may be used alone or in combination with two or more acid generators.

In the photoresist composition of the present invention, in order to ensure the photosensitivity and developability of the photoresist, the amount of the acid generator (B) is 100 parts by weight of the polymer resin (A) or 100 parts by weight of a mixture of the resin (A1) and the resin (A2). It is generally about 0.1 to about 20 parts by weight, particularly preferably about 0.5 to about 10 parts by weight. If the amount of the acid generator (B) is less than about 0.1 part by weight, the photosensitivity and developability of the resulting resist may deteriorate. If the amount of the acid generator exceeds 20 parts by weight, the transparency of the photoresist composition to irradiation may be reduced, making it difficult to obtain a rectangular resist pattern.

additive

Various types of additives, such as acid diffusion regulators, aliphatic ring additives with acid dissociating groups, surfactants and sensitizers, can optionally be added to the photosensitive polymer resin photoresist composition of the present invention.

The acid diffusion regulator controls the diffusion phenomenon of the acid generated from the acid generator (B) when the photoresist film composition is exposed to suppress unwanted chemical reaction from occurring in the unexposed portion.

The addition of an acid diffusion regulator further improves the storage stability of the resulting photosensitive resin photoresist composition and the resolution of the resist. In addition, the addition of an acid diffusion regulator suppresses the change in the line width of the resist pattern due to the change in post-exposure retardation (PED) between exposure and development, thereby obtaining a composition having very excellent processing stability.

Nitrogen-containing organic compounds whose basicity does not change during exposure or heating to form a resist pattern are preferred as acid diffusion regulators.

Examples of such nitrogen-containing organic compounds include compounds of the following general formula (6) (hereinafter referred to as "nitrogen-containing compound (a)").

N (R ¹⁶ ) ₃

Wherein R ¹⁶ is each a hydrogen atom, a substituted or unsubstituted linear, branched, or cyclic alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, a compound having two nitrogen atoms in the molecule ( Hereinafter referred to as "nitrogen-containing compound (b)"; Polyamino compounds and polymers having three or more nitrogen atoms in the molecule (hereinafter referred to as "nitrogen containing compound (c)"); Amide group-containing compounds, urea compounds, and other nitrogen-containing heterocyclic compounds.

Examples of the nitrogen-containing compound (a) include mono (cyclo) alkylamines such as n-hexyl amine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, and cyclohexylamine; Di (cyclo) alkylamines such as di-n-butylamine, di-n-pentylamine, di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonyl Amines, di-n-decylamine, cyclohexylmethylamine, and dicyclohexylamine; Tri (cyclo) alkylamines such as triethylamine, tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-heptylamine, tri -n-octylamine, tri-n-nonylamine, tri-n-decylamine, cyclohexyldimethylamine, methyldicyclohexylamine, and tricyclohexylamine; And aromatic amines such as aniline, N-methylaniline, N, N-dimethylaniline, 2-methylaniline, 3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine, triphenylamine, and Naphthylamine is included.

Examples of the nitrogen-containing compound (b) include ethylenediamine, N, N, N ', N'-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4' -Diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl)- 2- (4-aminophenyl) propane, 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis [1- (4-aminophenyl) -1-methylethyl] benzene, 1,3-bis [1- (4-aminophenyl) -1-methylethyl] benzene, bis (2-dimethylamino Ethyl) ether, and bis (2-diethylaminoethyl) ether.

Examples of the nitrogen-containing compound (c) include polymers of polyethyleneimine, polyallylamine, and 2-dimethylaminoethylacrylamide.

Examples of the amide group-containing compound include Nt-butoxycarbonyl group-containing amino compounds such as Nt-butoxycarbonyl di-n-octylamine, Nt-butoxycarbonyl di-n-nonylamine, and Nt-butoxycar Bonyl di-n-decylamine, Nt-butoxycarbonyl dicyclohexylamine, Nt-butoxycarbonyl-1-adamantylamine, Nt-butoxycarbonyl-N-methyl-1-adamantylamine , N, N-di-t-butoxycarbonyl-1-adamantylamine, N, N-di-t-butoxycarbonyl-N-methyl-1-adamantylamine, Nt-butoxycar Bonyl-4,4'-diaminodiphenylmethane, N, N'-di-t-butoxycarbonylhexamethylenediamine, N, N, N'N'-tetra-t-butoxycarbonylhexamethylenediamine , N, N'-di-t-butoxycarbonyl-1,7-diaminoheptane, N, N'-di-t-butoxycarbonyl-1,8-diaminooctane, N, N'- Di-t-butoxycarbonyl-1,9-diaminononane, N, N'-di-t-butoxycarbonyl-1,10-diaminodecane, N, N'-di-t-part Oxycarbonyl-1,12-diamino degree CAN, N, N'-di-t-butoxycarbonyl-4,4'-diaminodiphenylmethane, Nt-butoxycarbonylbenzimidazole, Nt-butoxycarbonyl-2-methylbenzimidazole , Nt-butoxycarbonyl-2-phenylbenzimidazole, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, propion Amide, benzamide, pyrrolidone, and N-methylpyrrolidone.

Examples of urea compounds include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, and tri-n-butyl Thiourea is included.

Examples of nitrogen-containing heterocyclic compounds include imidazoles such as imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, benzimidazole, and 2-phenylbenzimidazole; Pyridine, for example pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2- phenylpyridine, 4-phenylpyridine, 2-methyl-4-phenylpyridine, nicotine, nicotinic acid, Nicotinamide, quinoline, 4-hydroxyquinoline, 8-oxyquinoline, and acridine; Piperazine such as piperazine and 1- (2-hydroxyethyl) piperazine; Pyrazine, pyrazole, pyridazine, quinoxaline, purine, pyrrolidine, piperidine, 3-piperidino-1,2-propanediol, morpholine, 4-methylmorpholine, 1,4-dimethylpiperazine , And 1,4-diazabicyclo [2.2.2] octane.

Among the nitrogen-containing organic compounds, the nitrogen-containing compound (a), the amide group-containing compound and the nitrogen-containing heterocyclic compound are particularly important.

Acid diffusion regulators may be used individually or in combination of two or more.

Aliphatic ring additives with acid dissociable groups improve dry etch resistance, pattern shape, and adhesion to the substrate.

Examples of such alicyclic ring additives include

Adamantane derivatives such as t-butyl 1-adamantanecarboxylate, t-butoxycarbonylmethyl 1-adamantanecarboxylate, di-t-butyl 1,3-adamantanedicar Carboxylate, t-butyl 1-adamantane acetate, t-butoxycarbonylmethyl 1-adamantane acetate, and di-t-butyl 1,3-adamantane diacetate; Deoxycholates such as t-butyl deoxycholate, t-butoxycarbonylmethyl deoxycholate, 2-ethoxyethyl deoxycholate, 2-cyclohexyloxyethyl deoxycholate, 3-oxocyclohexyl de Oxycholate, tetrahydropyranyl deoxycholate, and mevalonolactone deoxycholate; And litocholates such as t-butyl litocholate, t-butoxycarbonylmethyl lithocholate, 2-ethoxyethyl lithocholate, 2-cyclohexyloxyethyl lithocholate, 3-oxocyclohexyl lithocholate, tetrahydro Pyranyl litocholate, and mevalonolactone litocholate.

Aliphatic ring additives may be used individually or in combination of two or more.

Surfactants often improve applicability, scratchiness, developability and the like.

Examples of suitable surfactants include nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene n-octyl phenyl ether, polyoxyethylene n-nonyl Phenyl ether, polyethylene glycol dilaurate, and polyethylene glycol distearate; And commercially available products such as KP341 (manufactured by Shin-Etsu Chemical), POLYFLOW No. 75, no. 95 (manufactured by Chioeshi Chemical), FTOP EF301, EF303, EF352 (manufactured by Tochem Products), MEGAFAC F171, F173 (manufactured by Dainippon Ink & Chemicals), Fluorad FC430, FC431 (manufactured by Sumitomo 3M), Asahi Guard AG710, and Surflon S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (made by Asahi Glass) are included.

Surfactants can be used individually or in mixture of 2 or more.

The sensitizer increases the amount of acid produced upon exposure by absorbing the irradiation energy and transferring this energy to the acid generator (B). Therefore, a sensitizer improves the apparent photosensitivity of the photosensitive resin composition.

Examples of sensitizers include acetophenone, benzophenone, naphthalene, biacetyl, eosin, rose bengal, pyrene, anthracene, phenothiazine, and the like.

A sensitizer can be used individually or in mixture of 2 or more.

The addition of dyes or pigments facilitates the visualization of the latent image of the exposed portions, reducing the halation effect upon exposure. Use of an adhesion improving agent improves adhesion to the substrate.

Low molecular weight alkali solubility modifiers, halation inhibitors, storage stabilizers, antifoaming agents and the like containing an alkali-soluble resin, an acid dissociable protecting group described below may be considered as other additives within the scope of the present invention.

Preparation of Composition Solution

The photosensitive photoresist resin composition of the present invention generally dissolves the photoresist composition in a solvent such that the total amount of solids is from about 5 to about 50 weight percent, preferably from about 10 to about 25 weight percent, and the pore diameter is, for example, about The solution is filtered to a composition solution using a 0.2 μm filter.

Examples of solvents useful in the preparation of the photoresist composition solutions include linear or branched ketones such as 2-butanone, 2-pentanone, 3-methyl-2-butanone, 2-hexanone, 4-methyl-2 -Pentanone, 3-methyl-2-pentanone, 3,3-dimethyl-2-butanone, 2-heptanone, and 2-octanone; Cyclic ketones such as cyclopentanone, 3-methylcyclopentanone, cyclohexanone, 2-methylcyclohexanone, 2,6-dimethylcyclohexanone, and isophorone; Propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol mono-n-propyl ether acetate, propylene glycol mono-i-propyl ether acetate, propylene glycol mono-n -Butyl ether acetate, propylene glycol mono-i-butyl ether acetate, propylene glycol mono-sec-butyl ether acetate, and propylene glycol mono-t-butyl ether acetate; Alkyl 2-hydroxypropionates such as methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, n-propyl 2-hydroxypropionate, i-propyl 2-hydroxypropionate Nate, n-butyl 2-hydroxypropionate, i-butyl 2-hydroxypropionate, sec-butyl 2-hydroxypropionate, and t-butyl 2-hydroxypropionate; Alkyl 3-alkoxypropionates such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, and ethyl 3-ethoxypropionate; And other solvents such as n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclohexanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n- Propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol di-n-propyl ether, diethylene glycol di-n-butyl ether, ethylene glycol monomethyl ether Acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-propyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, toluene, xylene, 2-hydroxy- 2-methylethyl propionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy Oxy-3-methylbutyrate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, 3-methyl-3-methoxybutylbutyrate, ethyl Acetate, n-propyl acetate, n-butyl acetate, methyl acetoacetate, ethyl acetoacetate, methyl pyruvate, ethyl pyruvate, N-methyl pyrrolidone, N, N-dimethylformamide, N, N-dimethyl Acetamide, benzyl ethyl ether, di-n-hexyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate , Ethyl benzoate, diethyl oxalate, diethyl maleate, gamma-butyrolactone, ethylene carbonate, and propylene carbonate.

The solvents can be used individually or in mixture of two or more.

Particularly suitable are the use of linear or branched ketones, cyclic ketones, propylene glycol monoalkyl ether acetates, alkyl 2-hydroxypropionates, alkyl 3-alkoxypropionates, gamma-butyrolactone and the like.

Formation of a resist pattern

The photosensitive photoresist resin composition of the present invention is useful as a chemically amplified resist.

In chemically amplified resists, the acid dissociable group in the resin (A) is dissociated by the action of the acid generated from the acid generator (B) when exposed to energy to form a carboxyl group. As a result, the solubility of the exposed portion of the resist in the alkali developer is increased so that the exposed portion is dissolved and removed in the alkaline developer to form a positive-tone resist pattern.

 The resist pattern is formed by applying a photoresist composition solution to a substrate, such as, for example, a silicon wafer or an aluminum coated wafer, using a suitable application method (e.g., rotation coating, cast coating, roll coating) to form a resist film. It forms from the photosensitive photoresist resin composition of this invention. Thereafter, the resist film is selectively prebaked (hereinafter referred to as "PB") and exposed to form a predetermined resist pattern. As an irradiation source to be used for exposure, visible light, ultraviolet light, extreme ultraviolet light, X-ray, electron beam, or the like can be appropriately selected depending on the type of acid generator (B). Particular preference is given to using extreme ultraviolet rays such as ArF excimer laser (wavelength: 193 nm), KrF excimer laser (wavelength: 248 nm), and F2 excimer laser (wavelength: 157 nm).

In the present invention, it is preferable to perform post-exposure baking (hereinafter referred to as "PEB"). PEB allows the acid dissociable group to be dissociated gently. The heating temperature for PEB will generally vary from about 30 to about 200 ° C., preferably from about 50 to about 170 ° C., although the heating conditions will vary depending on the composition of the photosensitive resin composition.

In order to maximize the potential of the photosensitive resin composition of the present invention, for example, an organic or inorganic antireflective film may be formed on a substrate as disclosed in Japanese Patent Publication No. 1994-12452. In addition, in order to prevent the influence of basic impurities in the ambient atmosphere, a protective film may be formed on the resist film as disclosed in Japanese Patent Publication No. 193-188598 or the like. These techniques may be employed in combination.

The exposed resist film is developed using an alkali developer to form a predetermined resist pattern.

Alkali developers used for development include one or more alkali compounds, for example sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia solution, ethylamine, n-propylamine , Diethylamine, di-n-propylamine, triethylamine, methyldiethylamine, ethyldimethylamine, triethanolamine, tetramethylammonium hydroxide, pyrrole, piperidine, choline, 1,8-diazabicyclo Aqueous alkali solution prepared by dissolving-[5.4.0] -7-undecane or 1,5-diazabicyclo- [4.3.0] -5-nonene in water.

The concentration of the aqueous alkali solution is generally about 10% by weight or less. If the concentration of the aqueous alkali solution exceeds 10% by weight, the unexposed portion may also be dissolved in the developer.

An organic solvent can also be added to aqueous alkali solution.

Examples of suitable organic solvents for use in the developing solution include ketones such as acetone, methyl ethyl ketone, methyl i-butyl ketone, cyclopentanone, cyclohexanone, 3-methylcyclopentanone, and 2,6-dimethyl Cyclohexanone; Alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, t-butyl alcohol, cyclopentanol, cyclohexanol, 1,4-hexanediol, and 1,4 Hexanedimethylol; Ethers such as tetrahydrofuran and dioxane; Esters such as ethyl acetate, n-butyl acetate, and i-amyl acetate; Aromatic hydrocarbons such as toluene and xylene; Phenol, acetonylacetone and dimethylformamide.

The organic solvent can be used individually or in mixture of 2 or more.

The amount of organic solvent used is 100% by volume or less of the aqueous alkali solution. When the amount of the organic solvent exceeds 100% by volume, developability may be lowered, and the exposed portion may remain undeveloped.

Surfactant can also be added to aqueous alkali solution.

In general, after development using an aqueous alkali solution, the resist film is washed with water.

Although the present invention has been described by way of preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail of the present invention without departing from the spirit thereof.

Claims (21)

To include acryl or methacrylic monomer unit of the formula (1),

Where R ^x is a group that is unstable enough to be released as its free radical form, T is carbon or phosphorus, and Z is any group that activates a C = S double bond to enable a reversible free radical addition fragmentation reaction. A polymer prepared by the Living Free Radical Process (LFRP) in the presence of a chain transfer agent (CTA). <Formula 1>

Where R ¹ represents a hydrogen atom or a methyl group, Each R ² is independently a linear or branched, unsubstituted or substituted alkyl group having 1 to 4 carbon atoms, or a bridged or unbridged, unsubstituted or substituted monovalent aliphatic ring hydrocarbon group having 4 to 20 carbon atoms, provided that any two R ² groups are not the bridge or the bridge together with the carbon atom to which is bonded one of the two R ² groups, is optionally substituted with a second value hwandoen of 4-20 carbon atoms form an alicyclic hydrocarbon group and the remaining R ² groups are linear or branched, , An unsubstituted or substituted alkyl group having 1 to 4 carbon atoms. The polymer of claim 1, wherein the acrylic or methacrylic polymer resin comprises a steric bulky ester group. The polymer of claim 2, wherein the steric bulky ester group is selected from the group consisting of monocyclic, bicyclic, tricyclic and tetracyclic non-aromatic rings having 5 or more carbon atoms and combinations thereof. 4. The polymer of claim 3 wherein said steric bulky ester group comprises lactones in a cyclic structure. The polymer of claim 1 further comprising one or more additional repeat units of formula (2): <Formula 2>

Where E is a group derived from an unbridged or bridged, unsubstituted or substituted aliphatic ring hydrocarbon, and R ³ is a hydrogen atom, a trifluoromethyl or methyl group. The polymer of claim 1 wherein the Mw is about 2,000 to 30,000. The polymer of claim 1, wherein the polydispersity is about 1.5 or less. The polymer of claim 1 wherein Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof. The compound of claim 1, wherein Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally A polymer selected from the group consisting of substituted heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl. The polymer of claim 1, wherein the end group of the polymer having a CTA fragment is treated to decompose the CTA fragment. Photo-acid generators and acrylic or methacrylic polymer resins, the polymers of formula

Where R ^x is a group that is unstable enough to be released as its free radical form, T is carbon or phosphorus, and Z is any group that activates a C = S double bond to enable a reversible free radical addition fragmentation reaction. A photoresist composition prepared by Living Free Radical Process (LFRP) in the presence of a chain transfer agent (CTA). The photoresist composition of claim 11, wherein the acrylic or methacrylic polymer resin comprises a steric bulky ester group. The photoresist composition of claim 12, wherein the three-dimensionally bulky ester group is selected from the group consisting of monocyclic, bicyclic, tricyclic and tetracyclic non-aromatic rings having 5 or more carbon atoms and combinations thereof. The photoresist composition of claim 13, wherein the three-dimensionally bulky ester group comprises a lactone of a cyclic structure. The photoresist composition of claim 11, wherein the polymer resin comprises a structure of Formula 1. 12. <Formula 1>

Where R ¹ represents a hydrogen atom or a methyl group, Each R ² is independently a linear or branched, unsubstituted or substituted alkyl group having 1 to 4 carbon atoms, or a bridged or unbridged, unsubstituted or substituted monovalent aliphatic ring hydrocarbon group having 4 to 20 carbon atoms, provided Unsubstituted or substituted carbon atoms, unsubstituted or substituted, with at least one R ² group being a linear or branched alkyl group of 1 to 4 carbon atoms or any two R ² groups are bridged or unbridged with the carbon atom to which the two R ² groups are attached; Form a divalent aliphatic ring hydrocarbon group and the remaining R ² groups are linear or branched, unsubstituted or substituted alkyl groups of 1-4 carbon atoms. The photoresist composition of claim 15, wherein the polymer further comprises one or more additional repeat units of formula (2): <Formula 2>

Where E is a group derived from an unbridged or bridged, unsubstituted or substituted aliphatic ring hydrocarbon, and R ³ is a hydrogen atom, a trifluoromethyl or methyl group. The photoresist composition of claim 11, wherein the Mw of the polymer resin is about 2,000 to 30,000. The photoresist composition of claim 11, wherein the polydispersity of the polymer resin is about 1.5 or less. The photoresist composition of claim 11, wherein Z is selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, heteroatom-containing hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and combinations thereof. . The compound of claim 11, wherein Z is hydrogen, optionally substituted alkyl, optionally substituted aryl, optionally substituted alkenyl, optionally substituted acyl, optionally substituted aroyl, optionally substituted alkoxy, optionally substituted heteroaryl, optionally substituted Heterocyclyl, optionally substituted alkylsulfonyl, optionally substituted alkylsulfinyl, optionally substituted alkylphosphonyl, optionally substituted arylsulfinyl, and optionally substituted arylphosphonyl . The photoresist composition of claim 11, wherein the end group of the polymer having the CTA fragment is treated to decompose the CTA fragment.