WO2009084775A1

WO2009084775A1 - Resist for e-beam lithography

Info

Publication number: WO2009084775A1
Application number: PCT/KR2008/002452
Authority: WO
Inventors: Do-Yeung Yoon; Ki-Bum Kim
Original assignee: Seoul National University Industry Foundation
Current assignee: Seoul National University Industry Foundation
Priority date: 2007-12-28
Filing date: 2008-04-30
Publication date: 2009-07-09
Anticipated expiration: 2010-06-30
Also published as: KR101061526B1; KR20090072993A

Abstract

A resist for E-beam lithography is provided. To be specific, provided is a negative resist in which two kinds of organic siloxane compounds are copolymerized. The resist for E-beam lithography makes it possible to manufacture a semiconductor device with further improved quality because the resist is highly sensitive to E-beam, easily prepared, and has uniform properties even though it is stored for a long time.

Description

Description RESIST FOR E-BEAM LITHOGRAPHY

Technical Field

[1] The present disclosure relates to a resist for E-beam lithography, and more particularly, to a resist for E-beam lithography, which is applicable to the manufacture of a semiconductor device with further improved quality because the resist is highly sensitive to E-beam, easily prepared, and has uniform properties even though it is stored for a long time. Background Art

[2] According to an increase in the complexity of a semiconductor manufacturing process and the integration degree of a semiconductor device, there is increasing demand for the formation of fine patterns.

[3] Hydrogen silsesquioxane (HSQ) is being most widely used as a negative electron beam (E-beam) resist at present. It is known that the use of HSQ makes it possible to form a sub-30-nm pattern that is finer than a pattern formed by another chemical amplification type negative resist. However, HSQ is known to have a ring-shaped configuration on the basis of a main chain of Si-O-Si. Particularly, HSQ, which has a configuration that a hydrogen atom is bonded to a silicon atom, is all made of an inorganic material.

[4] Since a hydrogen atom bonded to a silicon atom is very small in size, it is difficult to synthesize HSQ because a gellation time is too short in case of using a typical sol-gel synthesis. Furthermore, HSQ is disadvantageous in that resist properties are not uniform because HSQ is so unstable that a molecular weight changes over time in storage. In addition, since HSQ has low sensitivity to E-beam in comparison with an organic E-beam resist, it is also disadvantageous in that an exposure amount required to form a pattern should be increased.

[5] Therefore, it is necessary to overcome such disadvantages of HSQ as a negative E- beam resist.

Disclosure of Invention Technical Problem

[6] The present disclosure provides a resist for E-beam lithography, which has not only excellent resolution and sensitivity to E-beam, but also has uniform resist properties even though it is stored for a long time. Technical Solution [7] According to an exemplary embodiment, a resist for electron beam (E-beam) lithography is characterized in that a compound of Chemical Formula 1 and a compound of Chemical Formula 2 are copolymerized to form a copolymer, wherein a nunber- average molecular weight of the copolymer ranges from approximately 500 to approximately 30,000.

[8] <Chemical Formula 1> [9]

Si

R¹ O ^' OR '

R²O

[10] <Chemical Formula 2> [H] OR⁴ OR ⁷

R⁵O - Si Si ^■ OR ¹

R⁶O OR -

[12] where,

1 9 [13] R to R in Chemical Formulas 1 and 2 are hydrogen or alkyl group having a carbon nunber of 1 to 5;

[14] X in Chemical Formula 1 includes one of hydrogen, hydroxyl group, alkyl group having a carbon nunber of 1 to 5, alkoxy group having a carbon nunber of 1 to 5, norbornyl group, norbornyl alkyl group having a carbon nunber of 8 to 13, norbornenyl group, norbornenyl alkyl group having a carbon nunber of 8 to 13, haloalkyl phenyl group having a carbon nunber of 7 to 12, and haloalkyl phenyl alkyl group having a carbon nunber of 8 to 18; and

[15] Z in Chemical Formula 2 includes alkyl group having a carbon nunber of 1 to 6 or one of Chemical Formulas 3 through 5,

[16] <Chemical Formula 3>

[18] <Chemical Formula 4>

[20] <Chemical Formula 5>

[22] where R in Chemical Formula 5 is alkyl group having a carbon nunber of 2 to 6. [23] According to another exemplary embodiment, a resist for E-beam lithography is characterized in that a compound of Chemical Formula 9 and a compound of Chemical Formula 10 are copolymerized to form a copolymer, wherein a nunber- average molecular weight of the copolymer ranges from approximately 500 to approximately 30,000.

[24] <Chemical Formula 9> [25] A

Si

R¹¹ O ^{^}0R¹

OR¹

[26] <Chemical Formula 10>

[27] D

Si

R¹⁴O^' OR '

OR '

[28] where, [29] R to R in Chemical Formulas 9 and 10 are hydrogen or alkyl group having a carbon nunber of 1 to 5;

[30] A in Chemical Formula 9 includes one of norbornyl group, norbornyl alkyl group having a carbon nunber of 8 to 13, norbornenyl group, and norbornenyl alkyl group having a carbon nunber of 8 to 13; and

[31] D in Chemical Formula 10 includes one of hydrogen, hydroxyl group, alkyl group having a carbon nunber of 1 to 5, alkoxy group having a carbon nunber of 1 to 5, haloalkyl phenyl group having a carbon nunber of 7 to 12, and haloalkyl phenyl alkyl group having a carbon nunber of 8 to 18.

Advantageous Effects

[32] In case of using a resist for E-beam lithography according to the present invention, it is possible to manufacture a semiconductor device with further improved quality because the resist has high resolution and sensitivity to E-beam, can easily be prepared, and has uniform properties even though it is stored for a long time. Brief Description of Drawings

[33] Exemplary embodiments can be understood in more detail from the following description taken in conjunction with the accompanying drawings, in which:

[34] FIG. 1 is a graph illustrating analysis results of resist properties on resists of embodiments 1 through 8 of the present invention and a resist of a comparative example;

[35] FIG. 2 is an electron micrograph of a line-and-space pattern formed using the resist of the embodiment 2 of the present invention;

[36] FIG. 3 is an electron micrograph of a line-and-space pattern formed using the resist of the embodiment 7 of the present invention; and

[37] FIG. 4 is an electron micrograph of a line-and-space pattern formed using the resist of the embodiment 8 of the present invention. Mode for the Invention

[38] The present invention provides a resist for electron beam (E-beam) lithography in which a compound of following Chemical Formula 1 and a compound of following Chemical Formula 2 are copolymerized to form a copolymer. Herein, a nunber- average molecular weight of the copolymer ranges from approximately 500 to approximately 30,000.

[39] <Chemical Formula 1>

[40] x

Si

R¹ O ^' OR ^*

R²O

[41 ] <Chemical Formula 2> [42] OR⁴ OR ⁷

R⁵O - Si Si ^■ OR '

[43] where,

1 9 [44] R to R in Chemical Formulas 1 and 2 are hydrogen or alkyl group having a carbon nunber of 1 to 5;

[45] X in Chemical Formula 1 includes one of hydrogen, hydroxyl group, alkyl group having a carbon nunber of 1 to 5, alkoxy group having a carbon nunber of 1 to 5, norbornyl group, norbornyl alkyl group having a carbon nunber of 8 to 13, norbornenyl group, norbornenyl alkyl group having a carbon nunber of 8 to 13, haloalkyl phenyl group having a carbon nunber of 7 to 12, and haloalkyl phenyl alkyl group having a carbon nunber of 8 to 18; and

[46] Z in Chemical Formula 2 includes alkyl group having a carbon nunber of 1 to 6 or one of Chemical Formulas 3 through 5,

[47] <Chemical Formula 3>

[49] <Chemical Formula 4>

[51] <Chemical Formula 5>

.10

[53] where R in Chemical Formula 5 is alkyl group having a carbon nunber of 2 to 6. [54] The present invention also provides a resist for E-beam lithography in which a compound of Chemical Formula 9 and a compound of Chemical Formula 10 are copolymerized to form a copolymer. Herein, a nunber- average molecular weight of the copolymer ranges from approximately 500 to approximately 30,000.

[55] <Chemical Formula 9>

[57] <Chemical Formula 10> [58]

R¹¹¹O OR¹⁶

OR¹⁵

[59] where, [60] R to R in Chemical Formulas 9 and 10 are hydrogen or alkyl group having a carbon nunber of 1 to 5;

[61] A in Chemical Formula 9 includes one of norbornyl group, norbornyl alkyl group having a carbon nunber of 8 to 13, norbornenyl group, and norbornenyl alkyl group having a carbon nunber of 8 to 13; and

[62] D in Chemical Formula 10 includes one of hydrogen, hydroxyl group, alkyl group having a carbon nunber of 1 to 5, alkoxy group having a carbon nunber of 1 to 5, haloalkyl phenyl group having a carbon nunber of 7 to 12, and haloalkyl phenyl alkyl group having a carbon nunber of 8 to 18.

[63] In case of copolymerizing the compound of Chemical Formula 1 and the compound of Chemical Formula 2, or copolymerizing the compound of Chemical Formula 9 and the compound of Chemical Formula 10, an organic functional group bonded to a silicon atom is large so that it is relatively easier to control a reaction rate during sol- gel synthesis and the resist for E-beam lithography of the present invention exhibits good stability as well.

[64] The resist for E-beam lithography according to the present invention has a number- average molecular weight ranging from approximately 500 to approximately 30,000, as described above. The nunber- average molecular weight can easily be measured using a gel permeation chromatography that is well known in the art, and thus further description for it will not made herein.

[65] The nunber- average molecular weight may be in the range of approximately 1,000 to approximately 5,000. When the nunber- average molecular weight is smaller than approximately 1,000, the sensitivity becomes poor. On the contrary, when the nunber- average molecular weight exceeds approximately 5,000, the sensitivity is enhanced but the resolution is degraded because the polymer is enlarged.

[66] However, the polydispersity index of the resist for E-beam lithography according to the present invention is close to approximately 1 in the distribution of molecular mass, and therefore, the range of the weight average molecular weight is almost equal to the range of the nunber-average molecular weight. The polydispersity index may be in the range of approximately 1 to approximately 1.3.

[67] In case of polymerizing the compound of Chemical Formula 1 and the compound of

Chemical Formula 2, a ratio of a repeating unit derived from the compound of Chemical Formula 1 to a repeating unit derived from the compound of Chemical Formula 2 may somewhat differs from the case where they are used as reactants. This is affected by affinity for water and reaction characteristics of each functional group. For example, when a copolymer includes a nunber of monomers that are relatively hydrophobic and contain functional groups such as phenyl group and norbornenyl group, a relatively small amount of the hydrophobic monomers participate in reaction so that a fraction of the repeating unit may be relatively small. This is similar to the case of polymerizing the compounds of Chemical Formulas 9 and 10.

[68] In particular, when the resist for E-beam lithography is formed by copolymerizing the compound of Chemical Formula 1 and the compound of Chemical Formula 2, the compound of Chemical Formula 1 may be at least one selected from the group consisting of following Chemical Formulas 6 through 8. R to R in Chemical Formulas 6 through 8 are the same as those described in Chemical Formula 1.

[69] <Chemical Formula 6>

[71 ] <Chemical Formula 7>

[73] <Chemical Formula 8>

[75] where M in Chemical Formula 8 is a halogen group element. [76] When the resist for E-beam lithography is formed by copolymerizing a compound of Chemical Formula 9 and a compound of Chemical Formula 10, the compound of Chemical Formula 9 may be a compound of Chemical Formula 11 below, and the compound of Chemical Formula 10 may be at least one selected from the group consisting of a compound of Chemical Formula 12 and a compound of Chemical Formula 13. R to R in Chemical Formula 11 are the same as those described in Chemical Formula 9. R to R in Chemical Formulas 12 and 13 are the same as those described in Chemical Formula 10.

[77] <Chemical Formula 11>

[79] <Chemical Formula 12> [80]

Si

R¹⁴O ^' OR¹

OR'

[81] <Chemical Formula 13>

[83] where Q in Chemical Formula 13 is a halogen group element.

[84] When the resist for E-beam lithography is formed by copolymerizing the compound of Chemical Formula 9 and the compound of Chemical Formula 10, a molar ratio of a repeating unit of the compound of Chemical Formula 9 to a repeating unit of a compound contained in the copolymer may range from approximately 20% to approximately 40%. If the molar ratio of the repeating unit of the compound of Chemical Formula 9 is less than approximately 20%, the resolution is degraded. If the molar ratio of the repeating unit of the compound of Chemical Formula 9 is greater than approximately 40%, the resist for E-beam lithography is not developed well, thus leading to an increase in roughness at an edge portion of a pattern formed.

[85] In particular, hydroxyl group may be formed at an end of the resist for E-beam lithography according to the present invention. In this case, a molar ratio of the hydroxyl group to a functional group formed at an entire end of the resist for E-beam lithography may be approximately 50% or less.

[86] The chemical mechanism, which explains how the resist for E-beam lithography according to the present invention reacts to E-beam and is crosslinked after it is applied on a semiconductor substrate, is not clearly revealed yet. However, it is presuned that silanol group (-Si-OH) existing at the end of a polymer forming the resist is activated by E-beam to thereby trigger the crosslinking reaction. In addition, when a polymer contains haloalkyl phenyl group, it is presuned that a halogen atom is separated by E-beam, a radical is formed at alkyl group, and then the crosslinking reaction occurs due to the polymerization between alkyl radicals. In norbornenyl group, it is presuned that a double bond of the norbornenyl group is broken and one norbornenyl group bonds to an adjacent norbornenyl group or another alkyl radical so that the polymer is crosslinked.

[87] To prepare a copolymer using the compound of Chemical Formula 1 and the compound of Chemical Formula 2, the compound of Chemical Formula 1 and the compound of Chemical Formula 2 are put into a reaction chamber together with a solvent, then an acid or base as a catalyst is added, and a resultant mixture is stirred.

[88] The solvent may include water and an organic solvent such as alcohol (methanol, ethanol, isopropyl alcohol, n-propyl alcohol, or butyl alcohol), dimethylacetamide (DMAc), dimethylformamide, dimethyl sulfoxide (DMSO), and N-methylpyrrolidone, tetrahydrofurane (THF), but is not limited thereto.

[89] Although a weight ratio of the reactant (the compound of Chemical Formula 1 and the compound of Chemical Formula 2) to the solvent is not specifically limited, it may be in the range of, for example, approximately 20% to approximately 80%.

[90] The acid/base catalyst may use both the acid catalyst and the base catalyst that are used in general sol-gel reaction. To be specific, the acid catalyst may include an inorganic acid such as a hydrochloric acid a sulfuric acid, and a nitric acid, and an organic acid such as a p-toluene-sulfonic acid. The base catalyst may include tetram- ethylammoniun hydroxide (TMAH), tetrabutylammoniun hydroxide (TBuAOH), sodiun hydroxide (NaOH), sodiun carbonate, triethylamine, di-n-propylamine, or the like. However, the catalyst is not limited to the aforesaid, but other acid/base catalysts may be available. The content of the acid/base catalyst may range from approximately 0.005 mol to approximately 0.3 mol based on 1 mol of a total reactant.

[91] Although a desirable temperature of the copolymerization reaction may be selected from an appropriately elevated temperature, the copolymerization may be performed at a temperature ranging from approximately 40 ⁰C to approximately 90 ⁰C, e.g., preferably 50 ⁰C to 70 ⁰C. The copolymerization may be performed at a duration ranging from approximately 4 hours to approximately 16 hours, preferably at a duration ranging from approximately 8 hours to approximately 12 hours.

[92] Products resulted from the copolymerization can be separated through phase separation and drying.

[93] A method for preparing a copolymer using the compound of Chemical Formula 9 and the compound of Chemical Formula 10 is similar to the method for preparing the copolymer using the compound of Chemical Formula 1 and the compound of Chemical Formula 2.

[94] Hereinafter, the constitution and effect of the present invention will be more fully described according to specific embodiments and a comparative example, but it should be noted that the embodiments are merely provided to more clearly understand the present invention, not to limit the scope of the present invention.

[95] Preparation of copolymer

[96] <Embodiment 1>

[97] To prepare a copolymer, p-chloromethylphenyltrimethoxy silane (pCMPTMS) represented by following Chemical Formula 14 was used as the compound of Chemical Formula 1, and bis(triethoxysilyl)ethane (BTESE) represented by following Chemical Formula 15 was used as the compound of Chemical Formula 2. Then, pCMPTMS and BTESE were copolymerized.

[98] <Chemical Formula 14>

[100] <Chemical Formula 15>

[101] C,H_RO OC₂ H₅

C₂ KO OC₂H₅

C₂ H₆O OC₂ H₅

[102] First, nitrogen was supplied into a reaction chamber where a circulator was installed, and an internal pressure was then adjusted to 1 atm. Thereafter, pCMPTMS and BTESE as monomers were put into the reaction chamber at a molar ratio of 50:50, and tetrahydrofurane (THF) solvent was mixed with pCMPTMS and BTESE such that the concentration of the reactant (pCMPTMS and BTESE) became 40 wt%. Afterwards, a hydrochloric acid to be used as a catalyst was measured such that a molar ratio of the hydrochloric acid to the monomer was 0.03. A molar ratio between water and the reactant (pCMPTMS and BTESE) was fixed to 10, and the hydrochloric acid and the reactant were then made to react with each other at 60 ⁰C for 6 hours.

[103] After the reaction, the catalyst was separated through phase separation using ether/ water layers, and remaining moisture of the ether layer was removed with magnesiun sulfate (MgSO ). After that, ether was removed using a rotary vactun evaporator to obtain a product.

[104] The nunber- average molecular weight of the product was measured using a gel permeation chromatography (made by Wasters Company). A polystyrene standard was used as a standard. A resulting measured nunber- average molecular weight was 1,200.

[105] <Embodiment 2>

[106] A reaction product was obtained using the same method of the embodiment 1 except that potassiun hydroxide (KOH) was used as a catalyst instead of the hydrochloric acid. A nunber- average molecular weight was measured through the same method, and a resulting measured nunber- average molecular weight was 3,000.

[107] <Embodiment 3>

[108] A reaction product was obtained using the same method of the embodiment 1 except that a molar ratio between pCMPTMS and BTESE as monomers was set to 90:10. A nunber- average molecular weight was measured through the same method, and a resulting measured nunber- average molecular weight was 1,100.

[109] <Embodiment 4>

[110] To prepare a copolymer, [(bicycloheptenyl)ethyl]triethoxy silane (BHET) represented by following Chemical Formula 16 was used as the compound of Chemical Formula 1, and BTESE represented by Chemical Formula 15 was used as the compound of Chemical Formula 2. Then, BHET and BTESE were copolymerized.

[I l l] <Chemical Formula 16>

[113] First, nitrogen was supplied into a reaction chamber where a circulator was installed, and an internal pressure was then adjusted to 1 atm. Thereafter, BHET and BTESE as monomers were put into the reaction chamber at a molar ratio of 70:30, and tetrahy- drofurane (THF) solvent was mixed with BHET and BTESE such that the concentration of the reactant (BHET and BTESE) became 30 wt%. Afterwards, a hydrochloric acid to be used as a catalyst was measured such that a molar ratio of the hydrochloric acid to the monomer was 0.03. A molar ratio between water and the reactant (BHET and BTESE) was fixed to 3, and the hydrochloric acid and the reactant were then made to react with each other at 60 ⁰C for 6 hours. After the reaction, a product was obtained using the same method of the embodiment 1. A nunber- average molecular weight was measured through the same method, and a resulting measured nunber- average molecular weight was 1,450.

[114] <Embodiment 5>

[115] A reaction product was obtained using the same method of the embodiment 4 except that a molar ratio between BHET and BTESE as monomers was set to 60:40. A nunber- average molecular weight was measured through the same method, and a resulting measured nunber- average molecular weight was 1,600.

[116] <Embodiment 6> [117] A reaction product was obtained using the same method of the embodiment 4 except that a molar ratio between BHET and BTESE as monomers was set to 40:60. A number- average molecular weight was measured through the same method, and a resulting measured number- average molecular weight was 1,750.

[118] <Embodiment 7>

[119] To prepare a copolymer, BHET represented by Chemical Formula 16 was used as the compound of Chemical Formula 9, and pCMPTMS represented by Chemical Formula 14 was used as the compound of Chemical Formula 10. Then, BHET and pCMPTMS were copolymerized.

[120] First, nitrogen was supplied into a reaction chamber where a circulator was installed, and an internal pressure was then adjusted to 1 atm. Thereafter, BHET and pCMPTMS as monomers were put into the reaction chamber at a molar ratio of 20:80, and tetrahy- drofurane (THF) solvent was mixed with BHET and pCMPTMS such that the concentration of the reactant (BHET and pCMPTMS) became 30 wt%. Afterwards, a hydrochloric acid to be used as a catalyst was measured such that a molar ratio of the hydrochloric acid to the monomer was 0.03. A molar ratio between water and the reactant (BHET and pCMPTMS) was fixed to 3, and the hydrochloric acid and the reactant were then made to react with each other at 60 ⁰C for 6 hours. After the reaction, a product was obtained using the same method of the embodiment 1. A number- average molecular weight was measured through the same method, and a resulting measured number- average molecular weight was 1,500.

[121] <Embodiment 8>

[122] To prepare a copolymer, BHET represented by Chemical Formula 16 was used as the compound of Chemical Formula 9, and triethoxy silane represented by Chemical Formula 17 was used as the compound of Chemical Formula 10. Then, BHET and triethoxy silane were copolymerized.

[123] <Chemical Formula 17>

[124] H

C₂ H₃O

[125] First, nitrogen was supplied into a reaction chamber where a circulator was installed, and an internal pressure was then adjusted to 1 atm. Thereafter, BHET and triethoxy silane as monomers were put into the reaction chamber at a molar ratio of 30:70, and tetrahydrofurane (THF) solvent was mixed with BHET and triethoxy silane such that the concentration of the reactant (BHET and triethoxy silane) became 30 wt%. Afterwards, a hydrochloric acid to be used as a catalyst was measured such that a molar ratio of the hydrochloric acid to the monomer was 0.03. A molar ratio between water and the reactant (BHET and triethoxy silane) was fixed to 3, and the hydrochloric acid and the reactant were then made to react with each other at 60 ⁰C for 6 hours. After the reaction, a product was obtained using the same method of the embodiment 1. A nunber- average molecular weight was measured through the same method, and a resulting measured nunber- average molecular weight was 1,300.

[ 126] <Comparative example>

[127] A commercial hydrogen silsesquioxane (HSQ) made by the Dow Chemical company was used.

[128] Evaluation of resist properties

[129] The synthesized copolymer or polymer was dissolved into a methyl isobuthyl ketone solvent, and then a transparent thin film was obtained through a spin-coating. In particular, HSQ (made by the Dow Chemical company) was used in the comparative example.

[130] A baking process was not performed, and thirty five quadratic patterns having a size of 50 /M x 50 /M were formed on the coated thin film by adjusting an exposure amount

2 2 from 5 μC/cm to 900 μC/cm using a current of 800 pA through an E-beam lithographer of which an acceleration voltage is 19 keV. Then, the development is performed and thereafter thicknesses of the thin films remaining were measured. The results are shown in the graph of FIG. 1. A 25-wt% tetramethylammoniun hydroxide (TMAH) aqueous solution was used as a developing solution. The resist has a negative resist property that a portion unexposed by E-beam is removed but a portion exposed by E-beam remains intact.

[131] As shown in the graph of FIG. 1, the sensitivity of the resist of the embodiment 3 is improved by approximately 10% in comparison with HSQ (Comparative example), and the sensitivity of the resist of the embodiment 1 is improved by approximately 35% or more in comparison with HSQ. Furthermore, the sensitivity of the resist of the embodiment 2 is improved by approximately 50% or more in comparison with HSQ. In particular, it can be observed that the sensitivities of the resists of the embodiments 4 through 8 are remarkably improved compared to HSQ (Comparative example).

[132] Experiment of forming line-and-space [133] To test the performance of the resist for E-beam lithography according to the present invention, the resist for E-beam lithography according to the embodiment 3 was spin- coated on a silicon substrate, and a test for checking whether a line-and-space was formed well was carried out by setting a line width to 100 nm, 80 nm, 60 nm, 40 nm, and 30 nm, respectively. The experiment was carried out using a current ranging from

2

170 p A to 180 p A and using an exposure amount of 900 μC/cm . Resultant electron micrographs are shown in FIG. 2. Furthermore, the resists of the embodiments 7 and 8 were spin-coated on the silicon substrate, and then a test for checking whether a line- and-space was formed well was carried out by setting a linewidth to 30 nm. Resultant electron micrographs are shown in FIGS. 3 and 4, respectively.

[134] As shown in FIG. 2, it can be observed that a line-and-space is well formed even in the case where the linewidth is 30 nm as well as the case where the linewidth is 100 nm. Also, as shown in FIGS. 3 and 4, it can be observed that a line-and-space is well formed even in the case where the linewidth is 30 nm.

2

[135] Considering that the exposure amount of approximately 900 μC/cm is needed in case of using 20-keV E-beam when a sub-50 nm pattern is formed using typical HSQ, it can be understood that the same pattern can be formed only with remarkably small exposure amount if using the resist for E-beam according to the present invention. In particular, the resists of the embodiments 7 and 8 can realize excellent resolution even using very small amount of charge exposure in comparison with the case of using HSQ, thus making it possible to easily form a sub-30 nm pattern.

[136] Although the resist for E-beam lithography has been described with reference to the specific embodiments, it is not limited thereto. Therefore, it will be readily understood by those skilled in the art that various modifications and changes can be made thereto without departing from the spirit and scope of the present invention defined by the appended claims. Industrial Applicability

[137] As described above, the present invention is usefully applicable to a method for manufacturing a highly integrated semiconductor device.

Claims

[1] A resist for electron beam (E-beam) lithography characterized in that a compound of Chemical Formula 1 and a compound of Chemical Formula 2 are copolymerized to form a copolymer, wherein a number- average molecular weight of the copolymer ranges from approximately 500 to approximately 30,000:

<Chemical Formula 1> X

Si

R¹ O ^' OR ^:

R ²O

OR⁴ OR ⁷ \

\

R⁵O Si Z Si ^■ OR '

R^b0 OR ^' where,

1 9

R to R in Chemical Formulas 1 and 2 comprise hydrogen or alkyl group having a carbon number of 1 to 5;

X in Chemical Formula 1 comprises one of hydrogen, hydroxyl group, alkyl group having a carbon number of 1 to 5, alkoxy group having a carbon number of 1 to 5, norbornyl group, norbornyl alkyl group having a carbon number of 8 to

13, norbornenyl group, norbornenyl alkyl group having a carbon number of 8 to

13, haloalkyl phenyl group having a carbon number of 7 to 12, and haloalkyl phenyl alkyl group having a carbon number of 8 to 18; and

Z in Chemical Formula 2 comprises alkyl group having a carbon number of 1 to

6 or one of Chemical Formulas 3 through 5,

where R in Chemical Formula 5 is alkyl group having a carbon nunber of 2 to

6.

[2] The resist of claim 1, wherein the compound of Chemical Formula 1 comprises at least one selected from the group consisting of compounds represented by

Chemical Formulas 6 through 8:

where M in Chemical Formula 8 is a halogen group element.

[3] The resist of claim 1, wherein a molar ratio of hydroxyl group to a functional group bonded to an end of a silane group of the copolymer is approximately 50% or less. [4] The resist of claim 1, wherein a nunber- average molecular weight of the copolymer ranges from approximately 1,000 to approximately 5,000. [5] The resist of claim 1, wherein the copolymer has a polydispersity index ranging from approximately 1 to approximately 1.3. [6] A resist for E-beam lithography characterized in that a compound of Chemical

Formula 9 and a compound of Chemical Formula 10 are copolymerized to form a copolymer, wherein a nunber-average molecular weight of the copolymer ranges from approximately 500 to approximately 30,000:

<Chemical Formula 9> A

Si

13

R" 0 OR

OR¹²

D

R¹¹O OR¹⁸

OR¹⁵ where,

R to R in Chemical Formulas 9 and 10 comprise hydrogen or alkyl group having a carbon nunber of 1 to 5;

A in Chemical Formula 9 comprises one of norbornyl group, norbornyl alkyl group having a carbon nunber of 8 to 13, norbornenyl group, and norbornenyl alkyl group having a carbon nunber of 8 to 13; and

D in Chemical Formula 10 comprises one of hydrogen, hydroxyl group, alkyl group having a carbon nunber of 1 to 5, alkoxy group having a carbon nunber of 1 to 5, haloalkyl phenyl group having a carbon nunber of 7 to 12, and haloalkyl phenyl alkyl group having a carbon nunber of 8 to 18.

[7] The resist of claim 6, wherein the compound of Chemical Formula 9 comprises a compound of Chemical Formula 11, and the compound of Chemical Formula 10 comprises at least one selected from the group consisting of compounds of Chemical Formulas 12 and 13: <Chemical Formula 11>

H

Si

R¹< 0 ^" OR¹

OR¹

where Q in Chemical Formula 13 is a halogen group element.

[8] The resist of claim 6, wherein a molar ratio of a repeating unit of the compound of Chemical Formula 9 to a repeating unit of a compound contained in the copolymer ranges from approximately 20% to approximately 40%. [9] The resist of claim 6, wherein a molar ratio of hydroxyl group to a functional group bonded to an end of a silane group of the polymer is approximately 50% or less.

[10] The resist of claim 6, wherein a nunber- average molecular weight of the copolymer ranges from approximately 1,000 to approximately 5,000. [H] The resist of claim 6, wherein the copolymer has a polydispersity index ranging from approximately 1 to approximately 1.3.