Multi function photoacid generator and chemically amplified photoresist composition for thick layer comprising the same

Abstract

The present invention relates to a photoacid generator, and a chemically amplified photoresist composition for a thick film including the same, wherein the photoacid generator has excellent solubility and sensitivity, and also has an anti-corrosion effect, in addition to the effect as a photoacid generator. Thus, a chemically amplified photoresist composition for a thick film including the photoacid generator reduces scum and/or footing at the exposed part after development. The photoacid generator represented by the following Chemical Formula 1: ##STR00001## In Chemical Formula 1, the definition of each substituents is the same as the detail description of the specification.

Claims

1. A photoacid generator represented by Chemical Formula 1: ##STR00011## wherein, in the Chemical Formula 1, R.sub.1, R.sub.2, and R.sub.6 are each independently hydrogen, or a C.sub.1-10 alkyl group substituted with one or more C.sub.1-20 alkylene dithiol groups, at least one of R.sub.1, R.sub.2, and R.sub.6 is a C.sub.1-10 alkyl group substituted with one or more C.sub.1-20 alkylene dithiol groups, L.sub.1 is a substituted or unsubstituted C.sub.1-4 alkylene group that comprises a carbonyl connected to the nitrogen atom, or a carbonyl, L.sub.2 is a carbonyl, R.sub.3 is hydrogen, a C.sub.1-20 aliphatic functional group, or forms a C.sub.6-20 aromatic ring or a C.sub.5-20 aliphatic ring together with L.sub.1, and R.sub.7 is a C.sub.1-10 alkylfluoro group, a C.sub.1-10 alkoxy group, or a C.sub.1-10 alkylthio group.

2. The photoacid generator according to claim 1, wherein R.sub.3 is a C.sub.6-20 alkenylene group including at least one double bond and forms a C6-20 aromatic ring together with L.sub.1.

3. The photoacid generator according to claim 1, wherein R.sub.3 is a C.sub.5-20 alkylene group and forms a C5-20 aliphatic ring together with L.sub.1.

4. The photoacid generator according to claim 1, wherein L.sub.1 is represented by Chemical Formula 2: ##STR00012## wherein, in the Chemical Formula 2, R.sub.5 is a C.sub.1-3 alkylene group that includes a carbonyl connected to the nitrogen atom, or a carbonyl, R.sub.4 is hydrogen, a C.sub.1-20 aliphatic functional group, or forms, together with R.sub.3, one or more rings selected from the group consisting of benzene, naphthalene, and cyclohexane.

5. The photoacid generator according to claim 1, wherein the photoacid generator is one or more selected from the compounds represented by the following Chemical Formula 3 to Chemical Formula 5: ##STR00013## wherein, in the Chemical Formulae 3 to 5, n1 and n2 are each independently an integer, and 1≤n1≤20 and 1≤n2≤20.

6. A chemically amplified photoresist composition for a thick film, comprising the photoacid generator of claim 1.

7. A chemically amplified photoresist composition for a thick film, comprising the photoacid generator of claim 2.

8. A chemically amplified photoresist composition for a thick film, comprising the photoacid generator of claim 3.

9. A chemically amplified photoresist composition for a thick film, comprising the photoacid generator of claim 4.

10. A chemically amplified photoresist composition for a thick film, comprising the photoacid generator of claim 5.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

(1) Although various modifications can be made to the present invention and the present invention may have various forms, specific examples will be illustrated and explained in detail below. However, it should be understood that these are not intended to limit the present invention to specific disclosures, and that the present invention includes all modifications, equivalents, or replacements thereof without departing from the spirit and technical scope of the invention.

(2) Hereinafter, the action and effects of the present invention will be explained in more detail through specific examples. However, these examples are presented only as illustrations of the invention, and the scope of the right of the invention is not determined thereby.

Preparation Example of a Photoacid Generator

Preparation Example 1

(3) ##STR00008##

(4) Through the above synthesis process, NIT-2SH was prepared. The specific synthesis process is as follows.

(5) Synthesis of a Compound 2

(6) Into a flask containing the compound 1 (1.0 equiv.), 1-pentyne (1.5 equiv.), palladium acetate (3 mol %), 1,3,5-triaza-7-phosphaadamantane (9 mol %), and cesium carbonate (1.5 equiv.) were added, and acetonitrile was introduced, and the solution was stirred at 80 □ for 24 hours. After the reaction was finished, water was added, and the solution was extracted three times with dichloromethane. An organic layer obtained after the extraction was dried with magnesium sulfate and filtered, and then the solvent was removed. By purification by column chromatography, 23 g of the compound 2 was obtained with a yield of 85%.

(7) Synthesis of a Compound 3 Into a flask containing the compound 2 (1.0 equiv.), HO—NH.sub.3Cl (hydroxylamine hydrochloride, 1.5 equiv.), and NaHCO.sub.3 (1.5 equiv.) were added, and ethanol was introduced, and the solution was refluxed for 1 hour, and then the solvent was removed. Water and HCl (1N) were added, and the produced colorless solid was filtered, and then washed with diethylether to obtain 16 g of the compound 3 with a yield of 73%.

(8) Synthesis of a Compound 4

(9) The compound 3 (1.0 equiv.) was dissolved in chloroform, then pyridine (1.5 equiv.) was added, and the solution was cooled to 0° C. Tf.sub.2O (trifluoromethanesulfonic anhydride, 1.3 equiv.) was slowly added, and the mixture was stirred at room temperature for 3 hours. After the reaction was finished, water was added, the separated organic layer was washed with an aqueous solution of NaOH (0.2N), HCl (1N), and water, then dried with magnesium sulfate and filtered, and then the solvent was removed. By purification by column chromatography, 8.3 g of the compound 4 was obtained with a yield of 43%.

(10) Synthesis of NIT-2SH

(11) In a flask containing the compound 4 (1.0 equiv.), V-65 (1.2 equiv.) and 1,2-ethanedithiol (10 equiv.) were added, PGMEA was introduced, and a thiol-ene click reaction was progressed at 65° C. for 3 hours, thus preparing a compound of the structure of NIT-2SH. After the reaction was finished, water was added, the separated organic layer was washed with the water, dried with magnesium sulfate, and filtered, and then the solvent was removed. By purification by column chromatography, 3.1 g of NIT-2SH was obtained with a yield of 24%.

Comparative Preparation Example 1

(12) ##STR00009##

(13) Commercially available.

EXAMPLES

(14) Positive photoresist compositions of Examples 1 to 4 and Comparative Examples 1 to 5 were prepared with the components and contents described in the following Table 1. Here, the compounds represented by the following Chemical Formulas 9 and 10 are acrylic resins, the compound represented by the following Chemical Formula 11 is a PHS resin, NIT-2SH and NIT are photosensitive photoacid generator compounds (PAG), and Quencher is an acid diffusion inhibitor.

(15) ##STR00010##

(16) The components and contents of the photoresist compositions are shown in the following Table 1.

(17) TABLE-US-00001 TABLE 1 Comparative Comparative Comparative Comparative Example 1 Example 2 Example 3 Example 4 Example 1 Example 2 Example 3 Example 4 Acrylic 80 100 0 0 80 100 0 0 resin 1 Acrylic 0 0 80 100 0 0 80 100 resin 2 PHS resin 20 0 20 0 20 0 20 0 NIT-2SH 3 3 3 3 0 0 0 0 NIT 0 0 0 0 3 3 3 3 Quencher 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 (unit: parts by weight)

(18) Meanwhile, the contents described in Table 1 are based on solid content, the sum of the acrylic resin and PHS resin is 100 parts by weight, and NIT-2SH or NIT is respectively 3 parts by weight, and Quencher is 0.01 parts by weight, based on 100 parts by weight of the sum of the acrylic resin and PHS resin.

(19) Performance Evaluation

(20) (1) Solubility

(21) A time taken until the photoresist compositions prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were completely dissolved after preparation, was evaluated according to the following standard. The results are shown in the following Table 2.

(22) ⊚: dissolved within 30 minutes after preparation

(23) ∘: dissolved within 2 hours after preparation

(24) Δ: dissolved within 8 hours after preparation

(25) X: dissolved within 24 hours after preparation

(26) (2) Sensitivity

(27) On a Si substrate, the photoresist compositions prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were spin coated and dried in a hot plate at 120 □ for 2 hours, and then exposed using a step mask, additionally dried in a hot plate at 100 □ for 2 minutes, and then developed in an aqueous solution of TMAH (tetramethylammonium hydroxide). The amount of exposure at which they were developed to the bottom without remaining scum was evaluated as sensitivity. The results are shown in Table 2.

(28) (3) Anti-Corrosion Effect=Difference in the Footing of the Exposed Part after Development

(29) On a Si substrate, the photoresist compositions prepared in Examples 1 to 4 and Comparative Examples 1 to 4 were spin coated and dried on a hot plate at 120 □ for 2 hours, then exposed using a step mask, additionally dried in a hot plate at 100 □ for 2 minutes, and then developed in an aqueous solution of TMAH (tetramethylammonium hydroxide). A value reduced from the hole diameter of the top to the hole diameter of the bottom of the thick film resist pattern was measured as a footing length, which was an indicator of developability. The developability was measured according to the following standard, and the results are shown in Table 2.

(30) ⊚: footing length greater than 0 nm and less than 500 nm

(31) ∘: footing length greater than 500 nm and less than 1 μm

(32) Δ: footing length greater than 1 μm and less than 2 μm

(33) □: footing length greater than 2 μm

(34) TABLE-US-00002 TABLE 2 Sensitivity solubility (exposure amount, mJ/cm.sup.2) Footing length Example 1 ⊚ 340 ⊚ Example 2 ⊚ 510 ○ Example 3 ⊚ 380 ⊚ Example 4 ⊚ 550 ○ Comparative Δ 740 X Example 1 Comparative X 990 X Example 2 Comparative Δ 800 X Example 3 Comparative X 990 X Example 4

(35) From Table 2, it can be confirmed that the photoresist compositions according to Examples 1 to 4 of the present invention exhibit excellent effects in terms of solubility, sensitivity, and developability (anti-corrosion effect), compared to the photoresist compositions according to Comparative Examples 1 to 4.