Compounders for enhancing generation of chemical species
09952508 ยท 2018-04-24
Assignee
Inventors
Cpc classification
H01L21/02118
ELECTRICITY
G03F7/0045
PHYSICS
G03F7/0397
PHYSICS
H01L21/311
ELECTRICITY
G03F7/0382
PHYSICS
C08F220/302
CHEMISTRY; METALLURGY
C07C217/18
CHEMISTRY; METALLURGY
G03F7/038
PHYSICS
G03F7/0392
PHYSICS
International classification
C08F220/30
CHEMISTRY; METALLURGY
C07C217/18
CHEMISTRY; METALLURGY
G03F7/038
PHYSICS
H01L21/027
ELECTRICITY
H01L21/311
ELECTRICITY
H01L21/02
ELECTRICITY
Abstract
A reagent that enhances acid generation of a photoacid generator and composition containing such reagent is disclosed.
Claims
1. A composition, comprising: a compounder; a polymer containing an acid-dissociable substituent; and a precursor, wherein the compounder: has a diaryl ketone skeleton with at least one electron-donating group on at least one aromatic group of the diaryl ketone skeleton; absorbs a light, the wavelength of which is longer than 220 nm; is capable of sensitizing the precursor to generate a chemical species from the precursor; and wherein the electron-donating group is selected from the group consisting of an alkoxy group, aryloxy group, aryloxy group containing at least hereto atom, hydroxyl group, amino group, alkylthio group, and arylthio group.
2. The composition of claim 1, wherein the compounder has a molar absorption coefficient of the compounder at 400 nm when measured in a solution is equal to or lower than 200.
3. The composition according to claim 1, wherein the precursor is a photoacid generator (PAG).
4. The composition according to claim 1, further comprising: a compound capable of reacting with the chemical species.
5. The composition of claim 1, wherein the compounder has three or more electron-donating groups.
6. A polymer, comprising: a first moiety capable of acting as a photosensitizing moiety; and a second moiety that is to react with a chemical species and contains an acid-dissociable substituent, wherein the first moiety is a group connected with a compounder having a diaryl ketone skeleton with at least one electron-donating group on at least one aromatic group of the diaryl ketone skeleton; absorbs a light, the wavelength of which is longer than 220 nm; and is capable of sensitizing the precursor to generate a chemical species from the precursor, and wherein the electron-donating group is selected from the group consisting of an alkoxy group, aryloxy group, aryloxy group containing at least hereto atom, hydroxyl group, amino group, alkylthio group, and arylthio group.
7. The polymer according to claim 6, further comprising: a third moiety that is to generate the chemical species.
8. The polymer of claim 6, wherein the compounder has three or more electron-donating groups.
9. A method for manufacturing a device, wherein the method comprises: applying a solution of the composition of claim 1 to a member such that a coating film including the composition is formed on the member; and irradiating the coating film with at least one of an electromagnetic ray and a particle ray, such that a first portion of the coating film is exposed to the at least one of the electromagnetic ray and the particle ray while a second portion of the coating film is not exposed to the at least one of the electromagnetic ray and the particle ray; and removing the first portion.
10. The method according to claim 9, wherein the device comprises an interlayer insulating film, and the composition is used for formation of the interlayer insulating film.
11. The method according to claim 9, further comprising: etching the member such that a third portion of the member on which the first portion has been present is etched.
12. The method according to claim 9, wherein the electromagnetic ray is a light with a wavelength ranging between 350 nm and 400 nm.
13. The method according to claim 9, wherein an electromagnetic ray is used to irradiate the coating film with a light having a wavelength ranging between 310 nm and 400 nm.
14. The method according to claim 9, wherein the compounder has three or more electron-donating groups.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the drawings, which illustrate what is currently considered to be the best mode for carrying out several aspects of this disclosure:
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DETAILED DESCRIPTION
Experimental Procedures
Synthesis of 2,2,4,4-tetramethoxybenzophenone (Compounder A)
(5) 2.00 g of 2,2,4,4-tetrahydroxybenzophenone 3.68 g of dimethyl sulfate and 4.03 g of potassium carbonate are dissolved in 12.0 g of acetone. The mixture is stirred at reflux temperature for 8 hours. Next, the mixture is cooled to 25 degrees Celsius and is further stirred for 10 minutes after addition of 60.0 g of water and a deposit is filtrated. Then, the deposit is dissolved in 20.0 g ethyl acetate and the organic phase is washed with water. Thereafter, the ethyl acetate is distilled away, and the resultant is purified by recrystallization using 15.0 g of ethanol, thereby obtaining 1.40 g of 2,2,4,4-tetramethoxybenzophenone.
(6) ##STR00001##
Synthesis of bis-(2,4-dimethoxyphenyl)-dimethoxymethane
(7) 7.0 g of 2,2,4,4-tetramethoxybenzophenone is dissolved in 27.8 g of thionyl chloride. The mixture is stirred at reflux temperature for 5 hours. Next, thionyl chloride is distilled away and the resultant is dissolved in 15 g of toluene. Then, the prepared solution is added dropwise over 1 hour to 30.1 g of methanol solution containing 5.0 g of sodium methoxide at 5 degrees Celsius. Once the addition has been completed, the mixture is warmed up to 25 degrees Celsius while stirring for 2 hours. Then, the mixture is further stirred after an addition of 50 g of pure water. Next, the methanol is distilled away, the resultant is extracted by 35 g of toluene, and the organic phase is washed with water. Thereafter, toluene is distilled away, thereby obtaining 3.87 g of crude bis-(2,4-dimethoxyphenyl)-dimethoxymethane as an oil.
Synthesis of 2,2-bis-(2,4-dimethoxyphenyl)-1,3-dioxolane (Reagent A)
(8) 3.8 g of crude bis-(2,4-dimethoxyphenyl)-dimethoxymethane, 0.03 g of compher sulfonic acid and 2.03 g of ethyleneglycol are dissolved in 5.7 g of tetrahydrofran. The mixture is stirred at 25 degrees Celsius for 72 hours. Next, the organic solvents are distilled away and the resultant is dissolved in 11 g of dichloromethane. Thereafter, the mixture is further stirred after addition of 5% aqueous solution of sodium carbonate and the organic phase is washed with 5% aqueous solution of sodium carbonate and water. Thereafter, dichloromethane is distilled away, and the residue is purified by silica gel column chromatography (ethyl acetate:hexane:triethylamine=10:90:0.01), thereby obtaining 2.5 g of 2,2-bis-(2,4-dimethoxyphenyl)-1,3-dioxolane (Reagent A).
(9) ##STR00002##
Synthesis of 2,4-dimethoxy-4-methoxy-benzophenone (Compounder B)
(10) Synthesis of 2,4-dimethoxy-4-methoxy-benzophenone as a target substance is synthesized and obtained according to the synthesis of Compounder A mentioned above, except for using 2,4-dimethoxy-4-hydroxybenzophenone instead of 2,2,4,4-tetrahydroxybenzophenone for the synthesis of Compounder A.
(11) ##STR00003##
Synthesis of 2,4-dimethoxy-4-(2-vinyloxy-ethoxy)-benzophenone
(12) 2.00 g of 2,4-dimethoxy-4-hydroxybenzophenone, 2.48 g of 2-chloroethyl vinyl ether and 3.21 g of potassium carbonate are dissolved in 12.0 g of dimethyl formamide. The mixture is stirred at 110 degrees Celsius for 15 hours. Next, the mixture is cooled to 25 degrees Celsius and is further stirred after addition of 60.0 g of water, then extracted with 24.0 g toluene and the organic phase is washed with water. Thereafter, toluene is distilled away, thereby obtaining 3.59 g of 2,4-dimethoxy-4-(2-vinyloxy-ethoxy)-benzophenone.
Synthesis of 2,4-dimethoxy-4-(2-hydroxy-ethoxy)-benzophenone
(13) 3.59 g of 2,4-dimethoxy-4-(2-vinyloxy-ethoxy)-benzophenone, 0.28 g of pyridinium p-toluenesulfonate and 2.1 g of water are dissolved in 18.0 g of acetone. The mixture is stirred at 35 degrees Celsius for 12 hours. Next, the mixture is further stirred after addition of 3% aqueous solution of sodium carbonate, then extracted with 28.0 g ethyl acetate and the organic phase is washed with water. Thereafter, ethyl acetate is distilled away, thereby obtaining 3.04 g of 2,4-dimethoxy-4-(2-hydroxy-ethoxy)-benzophenone.
Synthesis of 2,4-dimethoxy-4-(2-methacryloxy-ethyl)-benzophenone (Compounder C)
(14) 3.0 g of 2,4-dimethoxy-4-(2-hydroxy-ethoxy)-benzophenone and 1.7 g of methacrylic anhydride are dissolved in 21 g of tetrahydrofuran. 1.2 g of triethylamine dissolved in 3.6 g of tetrahydrofuran is added dropwise to the tetrahydrofuran solution containing 2,4-dimethoxy-4-(2-hydroxy-ethoxy)-benzophenone over 10 minutes. Next, the mixture is stirred at 25 degrees Celsius for 3 hours. Thereafter, the mixture is further stirred after addition of water, then extracted with 30 g ethyl acetate and the organic phase is washed with water. Thereafter, ethyl acetate is distilled away, and the residue is purified by silica gel column chromatography (ethyl acetate:hexane=1:9), thereby obtaining 2.72 g of 2,4-dimethoxy-4-(2-methacryloxy-ethyl)-benzophenone.
(15) ##STR00004##
Synthesis of 2,4-dimethoxy-4-(2-acetoxy-ethoxy)-benzophenone
(16) Synthesis of 2,4-dimethoxy-4-(2-acetoxy-ethoxy)-benzophenone as a target substance is synthesized and obtained according to the synthesis of Compounder C mentioned above, except for using acetic anhydride instead of methacrylic anhydride for the synthesis of Compounder C.
Synthesis of (2,4-dimethoxyphenyl)-[4-(2-hydroxy-ethoxy)-phenyl]-dimethoxymethane
(17) Synthesis of (2,4-dimethoxyphenyl)-[4-(2-hydroxy-ethoxy)-phenyl]-dimethoxymethane as a target substance is synthesized and obtained according to the synthesis of bis-(2,4-dimethoxyphenyl)-dimethoxymethane mentioned above, except for using 2,4-dimethoxy-4-(2-acetoxy-ethyl)-benzophenone instead of 2,2,4,4-tetramethoxybenzophenone for the synthesis of bis-(2,4-dimethoxyphenyl)-dimethoxymethane.
Synthesis of 2-(2,4-dimethoxyphenyl)-2-[4-(2-hydroxy-ethoxy)-phenyl]-1,3-dioxolane
(18) Synthesis of 2-(2,4-dimethoxyphenyl)-2-[4-(2-hydroxy-ethoxy)-phenyl]-1,3-dioxolane as a target substance is synthesized and obtained according to the synthesis of the Reagent A mentioned above, except for using (2,4-dimethoxyphenyl)-[4-(2-hydroxy-ethoxy)-phenyl]-dimethoxymethane instead of bis-(2,4-dimethoxyphenyl)-dimethoxymethane for the synthesis of Reagent A.
2-(2,4-dimethoxyphenyl)-2-[4-(2-methacyloxy-ethoxy)-phenyl]-1,3-dioxolane (Reagent B)
(19) Synthesis of 2-(2,4-dimethoxyphenyl)-2-[4-(2-methacyloxy-ethoxy)-phenyl]-1,3-dioxolane as a target substance is synthesized and obtained according to the synthesis of the Compounder C mentioned above, except for using (2,4-dimethoxyphenyl)-[4-(2-hydroxy-ethoxy)-phenyl]-dimethoxymethane instead of 2,4-dimethoxy-4-(2-hydroxy-ethoxy)-benzophenone for the synthesis of Compounder C.
(20) ##STR00005##
(21) A solution containing 5.0 g of alpha-methacryloyloxy-gamma-butylolactone, 6.03 g of 2-methyladamantane-2-methacrylate, 4.34 g of 3-hydroxyadamantane-1-methacrylate, 0.51 g of dimethyl-2,2-azobis(2-methylpropionate), and 26.1 g of tetrahydrofuran is prepared. The prepared solution is added dropwise over 4 hours to 20.0 g of tetrahydrofuran placed in flask while stirring and boiling. After the addition of the prepared solution, the mixture is heated to reflux for 2 hours and cooled to room temperature. Addition of the mixture by drops to a mixed liquid containing 160 g of hexane and 18 g of tetrahydrofuran while vigorously stirring precipitates the copolymer. The copolymer is isolated by filtration. Purification of the copolymer is carried out by vacuum drying following two washings by 70 g of hexane, and thereby 8.5 g of white powder of the copolymer is obtained.
(22) ##STR00006##
(23) A solution containing 0.82 g of (2,4-dimethoxyphenyl)-[4-(2-methacryloxy-ethyl)-phenyl]-benzophenone, 3.0 g of alpha-methacryloyloxy-gamma-butylolactone, 2.6 g of 2-methyladamantane-2-methacrylate, 3.1 g of 3-hydroxyadamantane-1-methacrylate, 0.20 g of butyl mercaptane, 0.51 g of dimethyl-2,2-azobis(2-methylpropionate) and 11.2 g of tetrahydrofuran is prepared. The prepared solution is added dropwise over 4 hours to 8.0 g of tetrahydrofuran placed in flask while stirring and boiling under nitrogen atmosphere. After the addition of the prepared solution, the mixture is heated to reflux for 2 hours and cooled to room temperature. Addition of the mixture by drops to a mixed liquid containing 110 g of hexane and 11 g of tetrahydrofuran while vigorously stirring precipitates the copolymer. The copolymer is isolated by filtration. Purification of the copolymer is carried out by vacuum drying following two washings by 40 g of hexane, thereby obtaining 7.1 g of white powder of the copolymer (Resin B).
(24) ##STR00007##
(25) A solution containing 0.92 g of 2-(2,4-dimethoxyphenyl)-2-[4-(2-methacyloxy-ethoxy)-phenyl]-1,3-dioxolane, 3.0 g of alpha-methacryloyloxy-gamma-butylolactone, 2.6 g of 2-methyladamantane-2-methacrylate, 3.1 g of 3-hydroxyadamantane-1-methacrylate, 0.20 g of butyl mercaptane, 0.51 g of dimethyl-2,2-azobis(2-methylpropionate) and 11.2 g of tetrahydrofuran is prepared. The prepared solution is added dropwise over 4 hours to 8.0 g of tetrahydrofuran placed in flask while stirring and boiling under nitrogen atmosphere. After the addition of the prepared solution, the mixture is heated to reflux for 2 hours and cooled to room temperature. Addition of the mixture by drops to a mixed liquid containing 110 g of hexane and 11 g of tetrahydrofuran while vigorously stirring precipitates the copolymer. The copolymer is isolated by filtration. Purification of the copolymer is carried out by vacuum drying following two washings by 40 g of hexane, thereby obtaining 6.8 g of white powder of the copolymer (Resin C).
(26) ##STR00008##
(27) Preparation of Samples for Evaluation (the Evaluation Samples)
(28) Evaluation Samples 1-21 are prepared by dissolving in 2000 mg of cyclohexanone (i) 0.032 mmol of a PAG selected from a group consisting of diphenyliodonium nonafluorobutanesulfonate (DPI-PFBS), phenyl dibenzothionium nonafluorobutanesulfonate (PBpS-PFBS) and N-hydroxynaphtalimide nonafluorobutanesulfonate (NHNI-Nf), (ii) 450 mg of a resin selected from a group consisting of Resins A, B and C, and (iii) at least 0.017 mmol of one additive selected from a group consisting of Compounders and/or Reagents mentioned above, or (iv) 0 mmol of additive. Comparable samples are also prepared using 0.017 mmol of 2,4-diethylthioxanthen-9-one (DETX) as an additive. Table 1 shows detail of sample compositions.
(29) TABLE-US-00001 TABLE 1 Additive Resin PAG (composition ratio) Solvent Evaluation Sample 1 Resin A DPI-PFBS Cyclohexanone Evaluation Sample 2 Compounder A Evaluation Sample 3 Compounder B Evaluation Sample 4 Reagent A Evaluation Sample 5 Reagent A (0.7) Compounder A (0.3) Evaluation Sample 6 PBpS-PFBS Evaluation Sample 7 Compounder A Evaluation Sample 8 Compounder B Evaluation Sample 9 Reagent A (0.7) Compounder A (0.3) Evaluation Sample 10 NHNI-Nf Evaluation Sample 11 Compounder A Evaluation Sample 12 Compounder A [0.026 mmol] Evaluation Sample 13 Compounder A [0.051 mmol] Evaluation Sample 14 Compounder B Evaluation Sample 15 Reagent A Evaluation Sample 16 Resin B DPI-PFBS Evaluation Sample 17 PBpS-PFBS Evaluation Sample 18 NHNI-Nf Evaluation Sample 19 Resin C PBpS-PFBS Evaluation Sample 20 Compounder B (0.3) Evaluation Sample 21 NHNI-Nf Comparative sample 1 Resin A DPI-PFBS DETX Comparative sample 2 PBpS-PFBS DETX Comparative sample 3 NHNI-Nf DETX
(30) Evaluation of Sensitivity
(31) Before applying an Evaluation Sample to an Si wafer, hexamethyldisilazane (HMDS, Tokyo Chemical Industry, Tokyo, JP) is spin-coated at 2000 rpm for 20 seconds on the surface of an Si wafer and baked at 110 degrees Celsius for 1 minute. Then, an Evaluation Sample is spin-coated on the surface Si wafers that have been treated with HMDS at 2000 rpm for 20 seconds to form a coating film. The prebake of the coating film is performed at 110 degrees Celsius for 60 seconds. Then, the coating film of the Evaluation Sample is exposed to an ultraviolet (UV) light, the wavelength of which is 365 nm (i-line) output from a UV exposure system (HMW-661C-3 ORC manufacturing Co. LTD.). After the UV light exposure, a post-exposure-bake (PEB) is carried out at 110 degrees Celsius for 60 seconds. The coating film is developed with NMD-3 (tetra-methyl ammonium hydroxide 2.38%, Tokyo Ohka Kogyo) for 20 seconds at 25 degrees Celsius and rinsed with deionized water for 10 seconds. The thickness of the coating film measured using a film thickness measurement tool is approximately 500 nm. An Evaluation Sample is measured by ultraviolet-visible spectroscopy to evaluate the transmittance of films at 400 nm before UV light irradiation. Thereafter, a sensitivity (E.sub.0 sensitivity) is evaluated by measuring the dose size to form a pattern constituted by 100-micrometer lines where the thickness of the coating film is not zero and 100-micrometer spaces where the thickness of the coating film is zero using a UV exposure system, and dose for E.sub.0 sensitivity is calculated by means of a measurement of illuminance of UV source by 365 nm illuminometer (USHIO UIT-150, UVD-5365).
(32) Table 2 shows the dose sizes corresponding to E.sub.0 sensitivities measured for the Evaluation Samples 1 to 21. Formation of acid by an irradiation by i-line UV exposure is not observed for Evaluation Samples 1, 6 and 19. A tiny amount of acid is generated for Evaluation Sample 4. The E.sub.0 sensitivities are high for Evaluation Samples containing Compounder A, which has higher electron-donating ability than Compounder B.
(33) Resin B shows higher sensitivity than Compounder B, although the electron-donating ability of B-1 moiety included in Resin B acting as a photosensitizer is similar to that of Compounder B. An incorporation of B-1 moieties acting as photosensitizers into polymer enables homogeneous dispersion of the photosensitizers, which improves acid generation efficiency.
(34) Each of Evaluation Samples 5, 9 and 20 contains a photosensitizer and reagent that is protected by a protecting group such as dialkoxy acetal and to form a corresponding photosensitizer through reaction with acid. Such reagents and photosensitizers corresponding to such reagents have two pi-electron systems. In other words, such reagents and photosensitizers are two aromatic groups. An electronic interaction between the two pi-electron systems of such reagent is weaker than that of a corresponding photosensitizer. The two pi-electron systems of such photosensitizer interact mutually through pi electrons or unshared electron pair of carbonyl group of such photosensitizer. Due to such an electronic interaction in the photosensitizer, the photosensitizer can absorb a long-wavelength light.
(35) The conjugation length of such a reagent is shorter than that of a corresponding photosensitizer. In the photosensitizer, conjugation length is longer because of the electronic interaction of the two pi-electron systems through pi electrons or unshared electron pair of a carbonyl group.
(36) Addition of the reagent provides a composition containing the reagent and PAG having preservation stability. A film formed from such a composition has long-term reliability because the reagent has difficulty absorbing long-wavelength UV light due to a weaker electronic interaction between the two pi-electron systems. Such composition is especially useful for constituent material for film (e.g., insulating film or planarizing film of a display device), because suppressing the formation of acid can be achieved during normal operation of the display device.
(37) TABLE-US-00002 TABLE 2 Dose for E.sub.0 Dose at 365 nm Transmittance [mJ/cm.sup.2] at 400 nm Evaluation Sample 1 >1000 99.9 Evaluation Sample 2 160 99.7 Evaluation Sample 3 190 99.8 Evaluation Sample 4 950 99.9 Evaluation Sample 5 175 99.9 Evaluation Sample 6 >1000 99.8 Evaluation Sample 7 190 99.7 Evaluation Sample 8 225 99.8 Evaluation Sample 9 210 99.8 Evaluation Sample 10 210 99.7 Evaluation Sample 11 40 99.7 Evaluation Sample 12 30 99.7 Evaluation Sample 13 20 99.6 Evaluation Sample 14 50 99.7 Evaluation Sample 15 45 99.8 Evaluation Sample 16 140 99.8 Evaluation Sample 17 170 99.7 Evaluation Sample 18 40 99.7 Evaluation Sample 19 >1000 99.7 Evaluation Sample 20 170 99.7 Evaluation Sample 21 45 99.7 Comparative sample 1 125 87.6 Comparative sample 2 130 87.6 Comparative sample 3 30 87.3
(38) Alkoxy groups and aryloxy groups are electron-donating groups on aromatic group that can enhance the photosensitizing function of ketones. Besides a methoxy group, such include alkoxy groups having more than one carbon atom, such as ethoxy, n-propoxy group, i-propoxy, n-butyl, sec-butyl and t-butyl groups. Aryloxy groups such as phenoxy and naphthoxy groups are also available. Aryloxy groups containing at least one hetero atom such as pylidyloxy and thiophenyloxy groups can be selected as electron-donating groups.
(39) In addition to alkoxy and aryloxy groups, hydroxy, amino, alkylthio and arylthio groups can be introduced into an aromatic group such as electron-donating groups.
(40) It is preferable that at least one of such electron-donating groups including methoxy group is at the para-position or an ortho-position of the aromatic group with regard to the carbonyl group. In other words, it is preferable that such electron-donating group is positioned such that compounder can express the electron-donating nature.
(41) Each of Compounders D, E, F, and derivatives thereof is also preferably used as a photosensitizer. Each of the Compounders has electron-donating character that can function as a photosensitizer by UV light exposure because such compounder has at least one atom having an unshared electron pair. An electron of an unshared electron pair can be transferred to another moiety intramolecularly or another molecule intermolecularly.
(42) ##STR00009##
(43) Groups containing at least two chalcogen atomes, such as acetal, 1,3-dioxolane, thioacetal and 1,3-dithiolane, can be used as protecting groups for a carbonyl group.
(44)
(45) Typically, the molar absorption coefficient at 400 nm of a photosensitizer relating to an aspect of this disclosure in a solution is equal to or lower than 400. It is preferred that the molar absorption coefficient is equal to or lower than 200. More preferably, the molar absorption coefficient is equal to or lower than 100. The molar absorption coefficients of Compounder A and Compounder B are equal to or lower than 50.
(46) A typical ratio of absorbance at 365 nm (Ab.sub.365) to absorbance at 400 nm (Ab.sub.400) in a solution is equal to or greater than 10. A preferable Ab.sub.365/Ab.sub.400 in a solution is equal to or greater than 20. A more preferable Ab.sub.365/Ab.sub.400 in a solution is equal to or greater than 50. A preferable Ab.sub.365/Ab.sub.400 in a film is equal to or greater than 50. A more preferable Ab.sub.365/Ab.sub.400 in a film is equal to or greater than 100.
(47)
(48) A silicon wafer is provided. The surface of a silicon wafer is oxidized by heating the silicon wafer in the presence of oxygen gas.
(49) A solution of a chemically amplified resist (CAR) composition including Reagent A, resin, and PAG is applied to the surface of an Si wafer by spin coating to form a coating film. The coating film is prebaked.
(50) An irradiation of the coating film with a light, the wavelength of which is equal to or longer than 220 nm, is carried out through a mask after prebake of the Si wafer. A typical light source for the irradiation of the coating film is i-line or g-line. Initially, the PAG generates a small quantity of acid by absorbing the light directly. An encounter of reagent A with the small quantity of acid yields a deprotection reaction of Reagent A to form a photosensitizer in situ. The deprotection reaction of resin A is induced by acid generated by photoreaction of the photoacid generator and assistance by the photosensitizer formed in situ.
(51) The conjugation length of the photosensitizer is longer than the conjugation length of the reagent. The reagent has at least two pi-electron systems. By formation of a multiple bond through the deprotection reaction of the reagent, the electronic interaction between the at least two pi-electron systems in the photosensitizer is stronger than the electronic interaction between the at least two pi-electron systems in the reagent.
(52) The coating film and the silicon wafer are exposed to the light. After that, the remaining film is removed.
(53) An electronic device such as an integrated circuit is fabricated utilizing the processes shown in
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(57) ##STR00010##
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