KR20000047041A - Photoresist crosslinking monomer, polymer thereof and photoresist composition using the same - Google Patents

Abstract

PURPOSE: A crosslinking monomer for photoresist, the polymer and photoresist composition are provided, which is comprised photoacid generator, matrix polymer. The crosslinking monomer improves polymerization yield of photoresist polymer and is not reduced etching-resistance, heat-resistance and sticking property. CONSTITUTION: A crosslinking monomer is represented by the following formular 1. The photoresist polymer is represented by the following formular 4, wherein, R' and R'' is independently hydrogen or methyl, m is one of 1-10, p is one of 0-5, a is 1-50 mol%, b is 10-50 mol%, c is 0.1-50 mol%, R1, R2, R3 and R4 is independently hydregen; alkyl, ester, keton, carboxylic acid and acetal substituted side chain or main chain of carbon number of 1-10; alkyl, ester, keton, carboxylic acid or acetal substituted that containing at least one of hydroxide group. The photoresist composition comprises the crosslinking monomer represented by the formular 1, photoresist polymer, organic solvent and optionally photoacid generate.

Description

Novel Photoresist Crosslinking Monomers, Polymers thereof, and Photoresist Compositions Using the Same

The present invention relates to a novel photoresist crosslinking monomer, a polymer thereof, and a photoresist composition using the same, and more particularly, to a crosslinking monomer capable of remarkably improving the polymerization rate between monomers in the synthesis of a photoresist polymer. It relates to a photoresist polymer and a photoresist composition comprising the same.

In order to achieve high sensitivity in the process of forming microcircuits in semiconductor manufacturing, chemically amplified deep ultra violet (DUV) photoresists have been in the spotlight, and their composition is sensitive to photoacid generators and acids. It is prepared by blending the matrix polymer of the structure.

The action mechanism of the photoresist generates acid when the photoacid generator receives ultraviolet light from the light source, and crosslinking is formed between the matrix polymers by the generated acid so that the exposed portion is not dissolved in the developer. As a result, the image of the mask can remain as a negative image on the substrate.

By the way, since there is a limit in inducing crosslinking mutually only by a polymer, the crosslinking agent which can promote the crosslinking effect of each polymer is added.

In addition, the crosslinking agent promotes the bonding between the monomers constituting the photoresist polymer, thereby improving the polymerization yield of the photoresist polymer. For example, when the crosslinking agent is not used, if the monomer used for polymerization is 20 g, the amount of the polymer having a molecular weight of about 6000 obtained after polymerization is about 4.8 g and the yield is about 24%. However, when the amount of monomer is increased to 40 g, the amount of polymer obtained after polymerization is about 6 g, and the polymerization yield drops sharply to about 15%. Therefore, it is necessary to use a crosslinking agent in order to mass produce the photoresist polymer.

In order to solve the above problems, an object of the present invention is to provide a novel photoresist crosslinking monomer which improves the polymerization yield of a photoresist polymer and does not reduce the etching resistance, heat resistance and adhesion of the photoresist polymer. do.

The present invention also provides a photoresist polymer using the crosslinking monomer and a method of manufacturing the same.

Moreover, the photoresist composition manufactured using the said crosslinking monomer is provided.

The present invention also provides a semiconductor device manufactured using the photoresist composition.

In order to achieve the above object, the present invention provides a crosslinking monomer of the formula (1).

<Formula 1>

Where

R 'and R "are each hydrogen or methyl,

m is any one of 1 to 10,

R1 and R2 are each

Hydrogen:

Branched or main chain substituted alkyl having 1 to 10 carbon atoms;

Branched or main chain substituted esters having 1 to 10 carbon atoms;

Side or main chain substituted ketones having 1 to 10 carbon atoms;

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms;

Side or main chain substituted acetals having 1 to 10 carbon atoms;

Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); or

It is a C1-C10 side chain or main chain substituted acetal containing one or more hydroxyl group (-OH).

In addition, the present invention provides a photoresist polymer of the formula (2).

<Formula 4>

At this time,

k and n are each 1 or 2,

m is any one of 1 to 10,

p is any one of 0 to 5,

R 'and R "are hydrogen or methyl,

a is 1-50 mol% as a polymerization ratio of a normal photoresist monomer,

b is 10-50 mol% as a polymerization ratio of maleic anhydride,

c is 0.1 to 20 mol% as a polymerization ratio of the photoresist crosslinking monomer according to the present invention,

R1, R2, R3 and R4 are each

Hydrogen;

Branched or main chain substituted alkyl having 1 to 10 carbon atoms;

Branched or main chain substituted esters having 1 to 10 carbon atoms;

Side or main chain substituted ketones having 1 to 10 carbon atoms;

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms;

Side or main chain substituted acetals having 1 to 10 carbon atoms;

Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); or

It is a C1-C10 side chain or main chain substituted acetal containing one or more hydroxyl group (-OH).

Hereinafter, the present invention will be described in more detail with reference to specific examples.

As a result of numerous experiments, the inventors have found that the compound of formula 1 is suitable as a photoresist crosslinking monomer.

<Formula 1>

Where

R 'and R "are each hydrogen or methyl,

m is any one of 1 to 10,

R1 and R2 are each

Hydrogen:

Branched or main chain substituted alkyl having 1 to 10 carbon atoms;

Branched or main chain substituted esters having 1 to 10 carbon atoms;

Side or main chain substituted ketones having 1 to 10 carbon atoms;

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms;

Side or main chain substituted acetals having 1 to 10 carbon atoms;

Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); or

It is a C1-C10 side chain or main chain substituted acetal containing one or more hydroxyl group (-OH).

More preferably, the crosslinking monomer of Chemical Formula 1 according to the present invention is 1,3-butanediol diacrylate of Chemical Formula 2 or 1,4-butanediol diacrylate of Chemical Formula 3 below.

<Formula 2>

<Formula 3>

The crosslinking monomer according to the present invention improves the polymerization yield by crosslinking the photoresist polymer with each other. That is, since the crosslinking monomer according to the present invention has two double bonds, each double bond is connected to the photoresist polymer to form crosslinks between the photoresist polymers to improve the polymerization yield.

Preparation of Polymer for Photoresist

The crosslinking monomer according to the present invention may be dissolved in an organic solvent together with the photoresist monomer to prepare a photoresist copolymer.

The photoresist polymer as shown in the following formula (4) is a (bi) cycloalkene derivative (first monomer), maleic hydride (second monomer) and the crosslinking monomer according to the present invention in the presence of a conventional radical polymerization initiator It can manufacture by superposing | polymerizing under.

<Formula 4>

At this time,

k and n are each 1 or 2,

m is any one of 1 to 10,

p is any one of 0 to 5,

R 'and R "are hydrogen or methyl,

a is 1-50 mol% as a polymerization ratio of a normal photoresist monomer,

b is 10-50 mol% as a polymerization ratio of maleic anhydride,

c is 0.1 to 20 mol% as a polymerization ratio of the photoresist crosslinking monomer according to the present invention,

R1, R2, R3 and R4 are each

Hydrogen;

Branched or main chain substituted alkyl having 1 to 10 carbon atoms;

Branched or main chain substituted esters having 1 to 10 carbon atoms;

Side or main chain substituted ketones having 1 to 10 carbon atoms;

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms;

Side or main chain substituted acetals having 1 to 10 carbon atoms;

Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH);

Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); or

It is a C1-C10 side chain or main chain substituted acetal containing one or more hydroxyl group (-OH).

The molecular weight of the photoresist polymer according to the invention is preferably from 3,000 to 100,000.

In addition, the polymerization method may be carried out by bulk polymerization and solution polymerization, and the polymerization solvent is cyclohexanone, methyl ethyl ketone, benzene, toluene, dioxane, tetrahydrofuran, propylene glycol methyl ether acetate, dimethelformamide. A single solvent or a mixed solvent thereof can be used. Polymerization initiators include benzoyl peroxide, 2,2′-azobisisobutyronitrile (AIBN), acetyl peroxide, lauryl peroxide, t-butylperacetate, t-butylhydroperoxide, di-t-butyl Peroxide and the like can be used.

Example 1

Poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / 5-norbornene-2-carboxylic acid / 1 , 3-butanediol diacrylate) polymer.

(i) 0.1 mol of 2-hydroxyethyl 5-norbornene-2-carboxylate (first monomer) and (ii) 0.85 mol of t-butyl 5-norbornene-2-carboxylate (first monomer) And (iii) 0.05 mole of 5-norbornene-2-carboxylic acid (first monomer), and (iv) 1,3-butanediol diacrylate of a crosslinking agent of the above formula (2). 0.1 mol, (v) 1.0 mol maleic hydride is dissolved in tetrahydrofuran.

6.16 g of AIBN (azobisisobutyronitrile) was added to the resulting solution as a polymerization initiator, and then reacted at a temperature of about 67 ° C. under nitrogen or argon for 10 hours.

The polymer thus produced is precipitated in ethyl ether or hexane and dried to dry poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / 5-norbornene-2-carboxylic acid / 1,3-butanediol diacrylate) was obtained. (Yield: 35%)

<Formula 5>

poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / 5-norbornene 2-carboxylicacid / 1,3-butanediol diacrylate)

Wherein a1, a2, a3 and b are the polymerization ratios of the respective monomers constituting the polymer, c is the polymerization ratio of the crosslinking agent according to the present invention, and a1: a2: a3: b: c = 0.425: 0.05 It is preferable that it is: 0.025: 0.5: 0.05.

Example 2

Poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / 5-norbornene-2-carboxylic acid / 1 , 4-butanediol diacrylate)

Except for using 0.1 mole of 1,4-butanediol diacrylate of the formula (4) instead of 1,3-butanediol diacrylate (1,3-butanediol diacrylate) Poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / of formula 6 in the same manner as in Example 1 5-norbornene-2-carboxylic acid / 1,4-butanediol diacrylate) was obtained.

<Formula 6>

poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate) / t-butyl 5-norbornene-2-carboxylate / 5-norbornene 2-carboxylicacid / 1,4-butanediol diacrylate)

Wherein a1, a2, a3 and b are the polymerization ratios of each monomer constituting the polymer, and c represents the polymerization ratio of the crosslinking agent according to the present invention, and a1: a2: a3: b: c = 0.425: 0.05 It is preferable that it is: 0.025: 0.5: 0.05.

In the lithographic process according to the invention, the performance of the photoresist polymer was almost the same whether or not a crosslinking agent was added. However, when the crosslinking agent according to the present invention is used, the yield of the polymer is greatly improved. That is, when the crosslinking agent is not used, if the monomer used in the polymerization is 20g, the amount of the polymer having a molecular weight of 6000 obtained after the polymerization is about 4.8g and the yield is about 24%, while the amount of the monomer is 40g after the polymerization The amount of polymer obtained is about 6 g and the yield drops to about 15%. Therefore, it is not suitable for mass production. On the other hand, if the polymer using the crosslinking agent is 20 g of the monomer used in the polymerization, the amount of the polymer having a molecular weight of about 12000 after polymerization is about 7 g and the yield is about 35%. It is suitable for mass production because there is no change in yield about 35%. The polymer using a crosslinking agent has a molecular weight of 12000 and a poly distribution degree of about 2.0.

Preparation of Photoresist Composition

The invention also relates to a photoresist composition comprising a crosslinking monomer according to the invention.

A photoresist composition according to the present invention is prepared by dissolving a photoresist polymer comprising (i) a crosslinking monomer according to the present invention and (ii) a conventional photoresist monomer in (iii) an organic solvent.

In this case, in the case of a chemically amplified photoresist, (iii) a photoacid generator may be additionally added.

The photoacid generator is a sulfur salt-based or onium salt-based diphenyl iodo hexafluorophosphate, diphenyl iodo hexafluoro arsenate, diphenyl iodo hexafluoro antimonate, diphenyl paramethoxyphenyl triflate, diphenyl Paratoluenyl triflate, diphenylparaisobutylphenyl triflate, diphenylpara-t-butylphenyl triflate, triphenylsulfonium hexafluoro phosphate, triphenylsulfonium hexafluor arsenate, triphenylsulfonium hexa One or two or more of fluorine antimonate, triphenylsulfonium triflate and dibutylnaphthylsulfonium triflate may be used.

As the organic solvent, cyclohexanone, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propylene glycol methyl ether acetate, cyclohexanone, 2-methoxyethyl acetate, 2-heptanone , Isobutyl methyl kenone or other conventional organic solvents can be used.

Formation of Photoresist Pattern

After spin-coating a photoresist composition prepared according to the present invention on a silicon wafer to form a thin film, soft bake for 1 to 5 minutes in an oven or hot plate at 70 to 200 ° C., more preferably 80 to 150 ° C., and After exposing using an exposure apparatus or an excimer laser exposure apparatus, post-baking is performed at 10-200 degreeC more preferably at 100-200 degreeC. In this case, as the exposure source, ArF light, KrF light, E-beam, X-ray, EUV (extremely ultra violet), DUV (deep ultra violet) or the like may be used, and the exposure energy is preferably 1 to 100 mJ / cm 2. .

The wafer thus exposed is immersed and developed in a developer, for example, a 2.38% or 2.5% TMAH aqueous solution for preferably 40 seconds for a predetermined time, thereby obtaining an ultrafine pattern.

A high density semiconductor device can be manufactured using the photoresist pattern according to the present invention.

Although the present invention discloses only some embodiments of preparing a photoresist copolymer or photoresist composition using a crosslinking agent, the present invention is not limited thereto, and the present invention is not limited thereto. Of course, it also includes adding a crosslinking agent according to the present invention.

Claims (11)

Compound of formula 1, characterized in that used as a crosslinking monomer for photoresist. <Formula 1> Where R 'and R "are each hydrogen or methyl, m is any one of 1 to 10, R1 and R2 are each Hydrogen: Branched or main chain substituted alkyl having 1 to 10 carbon atoms; Branched or main chain substituted esters having 1 to 10 carbon atoms; Side or main chain substituted ketones having 1 to 10 carbon atoms; Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms; Side or main chain substituted acetals having 1 to 10 carbon atoms; Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); And It is selected from the group consisting of branched or main chain substituted acetals having 1 to 10 carbon atoms containing one or more hydroxyl groups (-OH). The compound of claim 1, wherein the compound is selected from the group consisting of Chemical Formula 2 and Chemical Formula 3. <Formula 2> <Formula 3> (i) a crosslinking monomer of formula (1), (ii) A photoresist polymer obtained by polymerization of one or two or more photoresist monomers. <Formula 1> Where R 'and R "are each hydrogen or methyl, m is any one of 1 to 10, R1 and R2 are each Hydrogen: Branched or main chain substituted alkyl having 1 to 10 carbon atoms; Branched or main chain substituted esters having 1 to 10 carbon atoms; Side or main chain substituted ketones having 1 to 10 carbon atoms; Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms; Side or main chain substituted acetals having 1 to 10 carbon atoms; Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); And It is selected from the group consisting of branched or main chain substituted acetals having 1 to 10 carbon atoms containing one or more hydroxyl groups (-OH). 4. The polymer of claim 3 wherein the photoresist polymer is a compound of formula (4). <Formula 4> At this time, k and n are each 1 or 2, m is any one of 1 to 10, p is any one of 0 to 5, R 'and R "are hydrogen or methyl, R1, R2, R3 and R4 are each Hydrogen; Branched or main chain substituted alkyl having 1 to 10 carbon atoms; Branched or main chain substituted esters having 1 to 10 carbon atoms; Side or main chain substituted ketones having 1 to 10 carbon atoms; Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms; Side or main chain substituted acetals having 1 to 10 carbon atoms; Branched or main chain substituted alkyl having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted esters having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted ketones having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); Branched or main chain substituted carboxylic acids having 1 to 10 carbon atoms containing one or more hydroxyl groups (—OH); And It is selected from the group consisting of branched or main chain substituted acetals having 1 to 10 carbon atoms containing one or more hydroxyl groups (-OH). The method of claim 4, wherein A is 1 to 50 mol% as a polymerization ratio of a normal photoresist monomer, B is 10 to 50 mol% as a polymerization ratio of maleic anhydride, C is 0.1 to 20 mol% as a polymerization ratio of the photoresist crosslinking monomer according to the present invention, The method of claim 4, wherein the photoresist polymer is Poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / 5-norbornene-2-carboxylic acid / 1 , 3-butanediol diacrylate) or, Poly (maleic anhydride / 2-hydroxyethyl 5-norbornene-2-carboxylate / t-butyl 5-norbornene-2-carboxylate / 5-norbornene-2-carboxylic acid / 1 , 4-butanediol diacrylate). (i) a photoresist polymer obtained by polymerization of a crosslinking monomer of formula (1) according to claim 1 with one or two or more photoresist monomers, (ii) organic solvent Photoresist composition comprising a. 8. The photoresist composition of claim 7, further comprising (iii) a photoacid generator. (a) applying the photoresist composition of claim 7 to an etched layer, (b) exposing the resultant using an exposure apparatus; (c) developing the resultant to obtain a photoresist pattern Forming a photoresist pattern comprising a. 10. The exposure apparatus of claim 9, wherein the exposure apparatus uses an exposure source selected from the group consisting of ArF light, KrF light, E-beam, X-ray, extremely ultra violet (EUV) and deep ultra violet (DUV). How to. The semiconductor device manufactured by the method of Claim 9.