RESIST COMPOSITION, METHOD OF FORMING RESIST PATTERN, COMPOUND, AND ACID DIFFUSION CONTROL AGENT

Abstract

A resist composition which generates an acid upon exposure and whose solubility in a developing solution is changed due to an action of the acid, the resist composition including a base material component whose solubility in a developing solution is changed due to the action of an acid; and a compound represented by Formula (d1) in which R.sup.b1 and R.sup.b2 each independently represents COO.sup., COOH, or a hydroxyl group, where at least one of R.sup.b1 and R.sup.b2 represents COO.sup., R.sup.b3, R.sup.b4, and R.sup.b5 each independently represents a hydroxyl group or a halogen atom, R.sup.b6 to R.sup.b8 each independently represents an alkyl group, nb3 represents an integer of 0 to 4, nb4 and nb5 each independently represents an integer of 0 to 2, nb6 to nb8 each independently represents an integer of 0 to 5, m represents 1 or 2, and q represents an integer of 0 to 3.)

##STR00001##

Claims

1. A resist composition which generates an acid upon exposure and whose solubility in a developing solution is changed due to an action of the acid, the resist composition comprising: a base material component (A) whose solubility in a developing solution is changed due to the action of an acid; and a compound (D1) represented by Formula (d1): ##STR00109## wherein R.sup.b1 and R.sup.b2 each independently represents COO.sup., COOH, or a hydroxyl group, where at least one of R.sup.b1 and R.sup.b2 represents COO.sup.; R.sup.b3, R.sup.b4, and R.sup.b5 each independently represents a hydroxyl group, a halogen atom, an alkyl group which may have a substituent, a fluorinated alkyl group which may have a substituent, or an alkoxy group which may have a substituent; R.sup.b6, R.sup.b7, and R.sup.b8 each independently represents an alkyl group, an alkenyl group, an aryl group, a monovalent cyclic aliphatic hydrocarbon group, or a halogen atom, where the alkyl group, the alkenyl group, the aryl group, or the monovalent cyclic aliphatic hydrocarbon group of R.sup.b6, R.sup.b7, and R.sup.b8 may be formed such that some or all hydrogen atoms are substituted with substituents; nb3 represents an integer of 0 to 4, nb4 and nb5 each independently represent an integer of 0 to 2, nb6, nb7, and nb8 each independently represent an integer of 0 to 5, and in a case where nb3 to nb8 each independently represent an integer of 2 or greater, a plurality of R.sup.b3's to R.sup.b8's may be the same as or different from one another; m represents 1 in a case where only one of R.sup.b1 and R.sup.b2 represents COO.sup. and represents 2 in a case where both of R.sup.b1 and R.sup.b2 represent COO.sup.; and q represents an integer of 0 to 3.

2. The resist composition according to claim 1, wherein the compound (D1) is represented by Formula (d1-1): ##STR00110## wherein R.sup.b11 and R.sup.b12 each independently represents COO.sup., COOH, or a hydroxyl group, where at least one of R.sup.b11 and R.sup.b12 represents COO.sup.; R.sup.b6, R.sup.b7, and R.sup.b8 each independently represent an alkyl group, an alkenyl group, an aryl group, a monovalent cyclic aliphatic hydrocarbon group, or a halogen atom, where the alkyl group, the alkenyl group, the aryl group, or the monovalent cyclic aliphatic hydrocarbon group of R.sup.b6, R.sup.b7, and R.sup.b8 may be formed such that some or all hydrogen atoms are substituted with substituents; nb3 represents an integer of 0 to 4, nb4 and nb5 each independently represents an integer of 0 to 2, nb6, nb7, and nb8 each independently represents an integer of 0 to 5, and in a case where nb3 to nb8 each independently represents an integer of 2 or greater, a plurality of R.sup.b3's to R.sup.b8's may be the same as or different from one another; m represents 1 in a case where only one of R.sup.b1 and R.sup.b12 represents COO.sup. and represents 2 in a case where both of R.sup.b11 and R.sup.b12 represent COO.sup..

3. The resist composition according to claim 1, wherein the base material component (A) contains a polymer compound (A1) having a constitutional unit (a1) that contains an acid decomposable group whose polarity is increased due to the action of an acid.

4. The resist composition according to claim 1, the resist composition further comprising an acid generator component (B) which generates an acid upon exposure.

5. A method of forming a resist pattern, comprising: forming a resist film on a support using the resist composition according to claim 1; exposing the resist film; and developing the exposed resist film to form a resist pattern.

6. A compound which is represented by Formula (d1): ##STR00111## wherein R.sup.b1 and R.sup.b2 each independently represents COO.sup., COOH, or a hydroxyl group, where at least one of R.sup.b1 and R.sup.b2 represents COO.sup.; R.sup.b3, R.sup.b4, and R.sup.b5 each independently represents a hydroxyl group, a halogen atom, an alkyl group which may have a substituent, a fluorinated alkyl group which may have a substituent, or an alkoxy group which may have a substituent; R.sup.b6, R.sup.b7, and R.sup.b8 each independently represents an alkyl group, an alkenyl group, an aryl group, a monovalent cyclic aliphatic hydrocarbon group, or a halogen atom, where the alkyl group, the alkenyl group, the aryl group, or the monovalent cyclic aliphatic hydrocarbon group of R.sup.b6, R.sup.b7, and R.sup.b8 may be formed such that some or all hydrogen atoms are substituted with substituents; nb3 represents an integer of 0 to 4, nb4 and nb5 each independently represents an integer of 0 to 2, nb6, nb7, and nb8 each independently represents an integer of 0 to 5, and in a case where nb3 to nb8 each independently represent an integer of 2 or greater, a plurality of R.sup.b3's to R.sup.b8's may be the same as or different from one another; m represents 1 in a case where only one of R.sup.b1 and R.sup.b2 represents COO.sup. and represents 2 in a case where both of R.sup.b1 and R.sup.b2 represent COO.sup.; and q represents an integer of 0 to 3.

7. The compound according to claim 6, which is represented by Formula (d1-1): ##STR00112## wherein R.sup.b11 and R.sup.b12 each independently represents COO.sup., COOH, or a hydroxyl group, where at least one of R.sup.b11 and R.sup.b12 represents COO.sup.; R.sup.b6, R.sup.b7, and R.sup.b8 each independently represents an alkyl group, an alkenyl group, an aryl group, a monovalent cyclic aliphatic hydrocarbon group, or a halogen atom, where the alkyl group, the alkenyl group, the aryl group, or the monovalent cyclic aliphatic hydrocarbon group of R.sup.b6, R.sup.b7, and R.sup.b8 may be formed such that some or all hydrogen atoms are substituted with substituents; nb3 represents an integer of 0 to 4, nb4 and nb5 each independently represents an integer of 0 to 2, nb6, nb7, and nb8 each independently represents an integer of 0 to 5, and in a case where nb3 to nb8 each independently represents an integer of 2 or greater, a plurality of R.sup.b3's to R.sup.b8's may be the same as or different from one another; m represents 1 in a case where only one of R.sup.b11 and R.sup.b12 represents COO.sup. and represents 2 in a case where both of R.sup.b11 and R.sup.b12 represent COO.sup..

8. An acid diffusion control agent which is formed from the compound according to claim 7.

Description

EXAMPLES

[0610] Hereinafter, the present invention will be described in detail based on the following examples, but the present invention is not limited to these examples.

Synthesis Examples of Compounds

Synthesis Example 1

[0611] 2-hydroxy-1-naphthoic acid (5 g), dichloromethane (100 g), and a salt (14.6 g) represented by Formula (A) were mixed, the mixed solution was added dropwise to trimethylamine (2.7 g), and the resulting solution was stirred at room temperature for 30 minutes. Thereafter, ion exchange water (60 g) was added to the reaction solution, the reaction solution was stirred at room temperature for 30 minutes, and the organic phase was separated. This washing operation was repeated nine times. The obtained organic layer was concentrated, thereby obtaining 10.2 g of a compound (D1-1) shown below.

[0612] The results obtained from .sup.1H NMR measurement performed on the compound (D1-1) are shown below.

[0613] .sup.1H NMR (400 MHz, DMSO-d6) (ppm)=18.89 (s, 1H), 9.61 (d, 1H), 7.86-7.75 (m, 15H), 7.61 (t, 2H), 7.30 (dt, 1H), 7.08 (dt, 1H), 6.89 (d, 1H).

##STR00103##

Synthesis Example 2

[0614] 9.7 g of a compound (D1-2) shown below was obtained in the same manner as in Synthesis Example 1 except that 1-hydroxy-2-naphthoic acid was used in place of 2-hydroxy-1-naphthoic acid.

[0615] The results obtained from .sup.1H NMR measurement performed on the compound (D1-2) are shown below.

[0616] .sup.1H NMR (400 MHz, DMSO-d6) (ppm)=8.20 (dd, 1H), 7.87-7.75 (m, 15H), 7.72 (d, 1H), 7.68 (d, 1H), 7.42 (dt, 1H), 7.34 (dt, 1H), 6.94 (d, 1H).

##STR00104##

Preparation of Resist Composition: Examples 1 and 2, and Comparative Examples 1 to 4

[0617] Respective components listed in Table 1 were mixed so as to be dissolved, thereby preparing resist compositions (a solid content concentration of approximately 3.1% by mass) of each example.

TABLE-US-00001 TABLE 1 Component (A) Component (B) Component (D) Component (F) Component (S) Example 1 (A)-1 (B)-1 (D1)-1 (D2)-5 (F)-1 (S)-1 [100] [9.3] [2.3] [4.2] [3.0] [3650] Example 2 (A)-1 (B)-1 (D1)-2 (D2)-5 (F)-1 (S)-1 [100] [9.3] [2.3] [4.2] [3.0] [3650] Comparative (A)-1 (B)-1 (D2)-1 (D2)-5 (F)-1 (S)-1 Example 1 [100] [9.3] [3.3] [4.2] [3.0] [3650] Comparative (A)-1 (B)-1 (D2)-2 (D2)-5 (F)-1 (S)-1 Example 2 [100] [9.3] [2.3] [4.2] [3.0] [3650] Comparative (A)-1 (B)-1 (D2)-3 (D2)-5 (F)-1 (S)-1 Example 3 [100] [9.3] [2.0] [4.2] [3.0] [3650] Comparative (A)-1 (B)-1 (D2)-4 (D2)-5 (F)-1 (S)-1 Example 4 [100] [9.3] [2.4] [4.2] [3.0] [3650]

[0618] The abbreviations in Table 1 have the following meanings. The numerical values in the parentheses are blending amounts (parts by mass).

[0619] (A)-1: A polymer compound represented by Chemical Formula (A)-1. This polymer compound (A-1) was obtained by performing radical polymerization on a monomer from which a constitutional unit constituting the polymer compound (A-1) was derived based on a predetermined molar ratio. The weight average molecular weight (Mw) of this polymer compound (A-1) in terms of standard polystyrene acquired by performing GPC measurement was 8900, and the molecular weight dispersity (Mw/Mn) thereof was 1.53. The copolymerization compositional ratio (the ratio (molar ratio) of each constitutional unit in the structural formula) (1/m) acquired by .sup.13C-NMR was 50:50.

##STR00105##

[0620] (B)-1: acid generator formed of compound (B-1) shown below

##STR00106##

[0621] (D1)-1: acid diffusion control agent formed of compound (D1-1) described below

[0622] (D1)-2: acid diffusion control agent formed of compound (D1-2) described below

[0623] (D2)-1: acid diffusion control agent formed of compound (D2-1) described below

[0624] (D2)-2: acid diffusion control agent formed of compound (D2-2) described below

[0625] (D2)-3: acid diffusion control agent formed of compound (D2-3) described below

[0626] (D2)-4: acid diffusion control agent formed of compound (D2-4) described below

[0627] (D2)-5: acid diffusion control agent formed of compound (D2-5) described below

##STR00107##

[0628] (F)-1: fluorine-containing polymer compound represented by Chemical Formula (F-1). This fluorine-based polymer compound (F-1) was obtained by performing radical polymerization on a monomer from which a constitutional unit constituting the fluorine-based polymer compound was derived based on a predetermined molar ratio. The weight average molecular weight (Mw) of this fluorine-containing polymer compound (F-1) in terms of standard polystyrene acquired by performing GPC measurement was 15600, and the molecular weight dispersity (Mw/Mn) thereof was 1.66. The copolymerization compositional ratio (the ratio (molar ratio) of each constitutional unit in the structural formula) (1/m) acquired by .sup.13C-NMR was 50:50.

[0629] (S)-1: mixed solution obtained by mixing propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, and cyclohexanone at mass ratio of 45:30:25.

##STR00108##

[0630] <Formation of Resist Pattern (Solvent Developing Process)>

[0631] A silicon substrate was coated with each resist composition of Examples 1 and 2 and Comparative Examples 1 to 4 using a spinner, and a prebake (PAB) treatment was performed thereon on a hot plate at a temperature of 110 C. for 60 seconds so that the composition was dried to form a resist film having a film thickness of 90 nm.

[0632] Next, the resist film was selectively irradiated with an ArF excimer laser (193 nm) using an ArF liquid immersion exposure device NSR-S610C (manufactured by Nikon Corporation; NA 1.30, Crosspole, 0.98/0.78).

[0633] Thereafter, the resist film was subjected to a post exposure bake (PEB) treatment at 95 C. for 60 seconds.

[0634] Next, solvent development was performed using butyl acetate at 23 C. for 30 seconds, and then a rinse treatment was performed.

[0635] As the result, a contact hole pattern (hereinafter, referred to as a CH pattern) having a hole diameter of 47 nm and a pitch of 86 nm (mask size of 53 nm) was formed.

[0636] [Evaluation of Optimum Exposure Amount (EOP)]

[0637] An optimum exposure amount EOP (mJ/cm.sup.2) at which a CH pattern having a target size was formed was acquired according to <formation of resist pattern (solvent developing process)>described above. The results are listed in Table 2 in the column of EOP (mJ/cm.sup.2).

[0638] [Evaluation of Depth of Focus (DOF) Characteristics]

[0639] In the formation of a resist pattern, a resist pattern was formed in the same manner as the formation of the resist pattern described above by appropriately shifting the focus in the vertical direction based on the Eop described above. At this time, the depth of focus (DOF, unit: m) in a range where a space portion was able to be formed was acquired. The results are listed in Table 2 in the column of DOF (m).

[0640] DOF indicates a range of the depth of focus where a resist pattern having a predetermined shape can be formed at the time of exposure by shifting the focus in the vertical direction with the same exposure amount, in other words, a range where a resist pattern according to a mask pattern can be obtained. As this range is increased (the value is increased), this means that the process margin is increased.

[0641] [Evaluation of in-Plane Uniformity of Pattern Dimension (CDU)]

[0642] With respect to the CH pattern formed in <formation of resist pattern (solvent developing process)>described above, the CH pattern was observed from above using a length measurement SEM (scanning electron microscope, acceleration voltage of 300 V, trade name: S-9380, manufactured by Hitachi High-Technologies Corporation), and hole diameters (nm) of 100 holes in the CH pattern were measured.

[0643] Three times (3) (unit: nm) the standard deviation () calculated from the measurement results was acquired. The results thereof are listed in Table 2 in the column of CDU (nm).

[0644] [Evaluation of Resist Pattern Shape]

[0645] The cross sectional shape of the CH pattern formed in <formation of resist pattern (solvent developing process)>described above was observed using a scanning electron microscope (trade name: SU-8000, manufactured by Hitachi High-Technologies Corporation, and the shape was evaluated based on the following evaluation criteria. The results are listed in Table 2 in the column of shape.

[0646] A: The cross sectional shape of the pattern was rectangular and the perpendicularity was high.

[0647] B: The perpendicularity of the cross sectional shape of the pattern was slightly inferior to that of A.

[0648] C: The cross sectional shape of the pattern was a tapered shape.

TABLE-US-00002 TABLE 2 Eop DOF CDU (mJ/cm.sup.2] (m) (nm) Shape Example 1 44.4 120 5.0 A Example 2 43.2 120 5.1 A Comparative Example 1 43.6 80 6.0 A Comparative Example 2 45.0 100 5.3 B Comparative Example 3 45.1 100 5.3 C Comparative Example 4 47.7 80 5.4 B

[0649] Based on the results listed in Table 2, it was confirmed that the resist compositions of Examples 1 and 2 to which the present invention had been applied had excellent lithography characteristics compared to the resist compositions of Comparative Examples 1 to 4.

[0650] While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.