WO2008018749A1 - Resin composition for forming fine patterns, method for fabricating semiconductor device using the composition and semiconductor device fabricated by the method - Google Patents
Resin composition for forming fine patterns, method for fabricating semiconductor device using the composition and semiconductor device fabricated by the method Download PDFInfo
- Publication number
- WO2008018749A1 WO2008018749A1 PCT/KR2007/003809 KR2007003809W WO2008018749A1 WO 2008018749 A1 WO2008018749 A1 WO 2008018749A1 KR 2007003809 W KR2007003809 W KR 2007003809W WO 2008018749 A1 WO2008018749 A1 WO 2008018749A1
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- WO
- WIPO (PCT)
- Prior art keywords
- water
- photoresist pattern
- coating film
- polymer
- resin composition
- Prior art date
Links
- 239000011342 resin composition Substances 0.000 title claims abstract description 34
- 239000000203 mixture Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 24
- 239000004065 semiconductor Substances 0.000 title claims abstract description 22
- 229920002120 photoresistant polymer Polymers 0.000 claims abstract description 60
- 239000011248 coating agent Substances 0.000 claims abstract description 48
- 238000000576 coating method Methods 0.000 claims abstract description 48
- 229920000642 polymer Polymers 0.000 claims abstract description 34
- 239000002904 solvent Substances 0.000 claims abstract description 31
- 239000003377 acid catalyst Substances 0.000 claims abstract description 25
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 12
- 125000003118 aryl group Chemical group 0.000 claims abstract description 8
- 239000002253 acid Substances 0.000 claims description 21
- 239000000758 substrate Substances 0.000 claims description 14
- 238000010438 heat treatment Methods 0.000 claims description 10
- 150000001412 amines Chemical class 0.000 claims description 6
- 239000004094 surface-active agent Substances 0.000 claims description 5
- 238000005530 etching Methods 0.000 claims description 4
- 150000001299 aldehydes Chemical class 0.000 claims description 3
- 150000001413 amino acids Chemical class 0.000 claims description 3
- 150000001720 carbohydrates Chemical class 0.000 claims description 3
- 235000014633 carbohydrates Nutrition 0.000 claims description 3
- 150000002576 ketones Chemical class 0.000 claims description 3
- 102000039446 nucleic acids Human genes 0.000 claims description 3
- 108020004707 nucleic acids Proteins 0.000 claims description 3
- 150000007523 nucleic acids Chemical class 0.000 claims description 3
- 102000004169 proteins and genes Human genes 0.000 claims description 3
- 108090000623 proteins and genes Proteins 0.000 claims description 3
- 239000000654 additive Substances 0.000 claims description 2
- 230000000996 additive effect Effects 0.000 claims description 2
- 230000009467 reduction Effects 0.000 abstract description 8
- 238000005389 semiconductor device fabrication Methods 0.000 abstract description 4
- 238000001459 lithography Methods 0.000 abstract description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 12
- 239000000463 material Substances 0.000 description 12
- 238000006243 chemical reaction Methods 0.000 description 10
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 230000007246 mechanism Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- WEVYAHXRMPXWCK-UHFFFAOYSA-N Acetonitrile Chemical compound CC#N WEVYAHXRMPXWCK-UHFFFAOYSA-N 0.000 description 3
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 3
- WQDUMFSSJAZKTM-UHFFFAOYSA-N Sodium methoxide Chemical compound [Na+].[O-]C WQDUMFSSJAZKTM-UHFFFAOYSA-N 0.000 description 3
- ZMANZCXQSJIPKH-UHFFFAOYSA-N Triethylamine Chemical compound CCN(CC)CC ZMANZCXQSJIPKH-UHFFFAOYSA-N 0.000 description 3
- 238000004132 cross linking Methods 0.000 description 3
- 125000002791 glucosyl group Chemical group C1([C@H](O)[C@@H](O)[C@H](O)[C@H](O1)CO)* 0.000 description 3
- 238000003384 imaging method Methods 0.000 description 3
- 238000004377 microelectronic Methods 0.000 description 3
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 239000006117 anti-reflective coating Substances 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 239000003021 water soluble solvent Substances 0.000 description 2
- OECNRSQLSUXGSO-JABUTEAWSA-N [(2R,3R,4S,5S)-3,4,5-triacetyloxy-6-[(2,2,2-trichloroacetyl)amino]oxan-2-yl]methyl acetate Chemical compound CC(=O)OC[C@H]1OC(NC(=O)C(Cl)(Cl)Cl)[C@@H](OC(C)=O)[C@@H](OC(C)=O)[C@@H]1OC(C)=O OECNRSQLSUXGSO-JABUTEAWSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 238000004587 chromatography analysis Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229940073584 methylene chloride Drugs 0.000 description 1
- 239000002808 molecular sieve Substances 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- FTVLMFQEYACZNP-UHFFFAOYSA-N trimethylsilyl trifluoromethanesulfonate Chemical compound C[Si](C)(C)OS(=O)(=O)C(F)(F)F FTVLMFQEYACZNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/004—Photosensitive materials
- G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
- G03F7/11—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers having cover layers or intermediate layers, e.g. subbing layers
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/004—Photosensitive materials
- G03F7/09—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers
- G03F7/091—Photosensitive materials characterised by structural details, e.g. supports, auxiliary layers characterised by antireflection means or light filtering or absorbing means, e.g. anti-halation, contrast enhancement
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/26—Processing photosensitive materials; Apparatus therefor
- G03F7/40—Treatment after imagewise removal, e.g. baking
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/027—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34
- H01L21/0271—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers
- H01L21/0273—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers characterised by the treatment of photoresist layers
Definitions
- the present invention relates to a resin composition for forming fine patterns that enables reduction in width of an engraved portion in a photoresist pattern during lithography in semiconductor device fabrication and a method for fabricating a semiconductor device by using the composition.
- Lithographic techniques are essential for obtaining reduction in sizes of patterns.
- the manufacture of microscopic structures in lithography must be made in view of not only directly imaging patterns on a substrate, but also producing masks used in such imaging.
- Typical lithographic processes involve formation of a patterned resist layer by patternwise exposing a radiation- sensitive resist to an imaging radiation.
- the image is subsequently developed by contacting the exposed resist layer with a material (typically an aqueous alkaline developer) to selectively remove portions of the resist layer to reveal the desired pattern.
- the pattern is subsequently transferred to an underlying material by etching the material in openings of the patterned resist layer. After the transfer is complete, the remaining resist layer is removed.
- Japanese Patent No. 3,071,401 suggests a micropattern-forming material which uses a water-soluble resin causing a crosslinking reaction with a resist in the presence of an acid to form a crosslinked film at the interface between a resist pattern and the micropattern-forming material by the acid supplied from the resist pattern and to strip the uncrosslinked portions.
- the resist pattern when the material is used to form a pattern, the resist pattern may be deformed by the action of an internal stress resulting from volume shrinkage of the resin during the crosslinking reaction.
- a resin composition for forming fine patterns comprising: a) a polymer having aromatic hydroxyl groups in which all or a part of the hydroxyl groups are substituted with a water-soluble group; and b) water or an aqueous mixture of water- miscible solvent whereby the composition is applied to a photoresist pattern to form a coating film and the water-soluble group is removed by an acid catalyst supplied from the photoresist pattern, to selectively make insoluble regions in the coating film.
- the polymer may be a novolac-type polymer, hydroxystyrene-type polymer or naphtol-type polymer, or a mixture thereof in which all or a part of the hydroxyl groups of the aromatic rings are substituted with a water-soluble group.
- the water-soluble group may be at least one selected from the group consisting of carbohydrates, nucleic acids, proteins, amino acids, ketones having an amine or hydroxyl group, aldehydes having an amine or hydroxyl group, and derivatives thereof.
- the polymer may be represented by Formula 1 below:
- the composition may comprise 1 to 50 parts by weight of the polymer and 50 to 99 parts by weight of the solvent.
- composition may further comprise at least one additive selected from acid diffusers, acid generators, acid quenchers and surfactants.
- a method for fabricating a semiconductor device comprising the steps of: forming a first photoresist pattern containing an acid catalyst on a semiconductor substrate; coating the first photoresist pattern with the resin composition to form a coating film; allowing the acid catalyst contained in the first photoresist to be supplied to the coating film to make insoluble regions in the coating film; developing and stripping the coating film with a developing solvent to form a second photoresist pattern; and etching the semiconductor substrate using the second photoresist pattern as a mask.
- the supply of acid catalyst from the first photoresist pattern may be promoted by heating the first photoresist pattern.
- the developing solvent may be water or an aqueous mixture of water-miscible solvent.
- patterns can be formed without limitation of exposure light wavelength by using fine photoresist patterns.
- FIG. 1 is a diagram schematically showing a lithographic process using a resin composition for forming fine patterns according to the present invention.
- FIG. 2 is a cross-sectional view illustrating a state in which a predetermined region insoluble in a developing solution is selectively formed in a coating film by a chemical reaction of a fine pattern forming resin composition contained in the coating film according to the present invention.
- the resin composition of the present invention comprises a) a polymer having aromatic hydroxyl groups in which all or a part of the hydroxyl groups are substituted with a water-soluble group; and b) water or an aqueous mixture of water-miscible solvent.
- the polymer is preferably a novolac-type polymer, hydroxystyrene-type polymer or naphtol-type polymer, or a mixture thereof in which all or a part of the hydroxyl groups of the aromatic rings are substituted with a water-soluble group.
- the solvent contained in the resin composition must be capable of dissolving the polymer, but be incapable of dissolving a photoresist layer. Taking into consideration this fact, preferred is water or an aqueous mixture of water-miscible solvent.
- the examples of the water-soluble solvent include isopropyl alcohol, 1-butanol, ethanol and methanol.
- the ratio of water to the water-soluble solvent may be in the range of 1 : 99 to 99 : 1 (w/w).
- the water-soluble group is at least one selected from the group consisting of carbohydrates, nucleic acids, proteins, amino acids, ketones containing an amine or hydroxyl group, aldehydes containing an amine or hydroxyl group, and derivatives thereof.
- the resin composition may consist of 1 to 50 parts by weight of the polymer and 50 to 99 parts by weight of the solvent.
- the contents out of the range defined above disad- vantageously cause an excessively high or low viscosity upon spin coating, thus making it difficult to control a film thickness.
- the acid catalyst diffused from the photoresist pattern is supplied into the coating film.
- removal reactions of water-soluble groups selectively occur in predetermined regions being in contact with the photoresist pattern and in regions to which the diffusing acid catalyst can reach.
- the moieties, where the water-soluble groups are removed, become insoluble in the solvent.
- the coating film includes both soluble and insoluble regions in developing solvents, thus achieving a selective solubility to the developing solvents.
- the unreacted portions of the coating film are dissolved in and stripped by the developing solvent having a selective solubility dependent upon chemical reaction of the resin composition of coating film, thereby enabling reduction in width of an engraved portion of photoresist pattern.
- polymer contained in the resin composition there may be used a polymer represented by Formula 1 below:
- n/m value of zero indicates that hydroxyl groups of side chain aromatic groups in polyhydroxystyrene are completely substituted with glucose groups. Meanwhile, the n/m value exceeding 999 disadvantageously involves considerable reduction in solubility to the solvent of the present invention.
- the glucose group of the polymer represented by Formula 1 is removed in the presence of an acid catalyst to generate polyhydroxystyrene represented by Formula 2 below:
- n 2 to 30,000
- the polyhydroxystyrene is insoluble in the developing solvent used to develop the coating film which is formed by coating a photoresist pattern with the resin composition of the present invention. Accordingly, after the removal of glucose groups in the presence of an acid catalyst, predetermined regions insoluble in the developing solution are made in the coating film. At this time, the acid catalyst from the photoresist pattern is diffused into the coating film. Thus, the removal reaction of water-soluble groups selectively occurs in predetermined regions of the coating film being in contact with the photoresist pattern and in regions to which the diffusing acid catalyst can reach. The moieties, in which the water-soluble groups are removed, become insoluble in the solvent.
- the coating film includes both soluble regions and insoluble regions, thus achieving a selective solubility.
- the resin composition may further comprise at least one selected from acid diffusers, acid generators, acid quenchers and surfactants.
- the acid diffuser elevates a diffusion ratio of acid which is supplied from a photoresist pattern to the coating film including the resin composition and enables the chemical reaction of polymer to occur from the surface of the coating to a larger depth thereof. As a result, the width of the engraved portion of photoresist pattern is reduced, thus achieving fine patterns.
- the acid generator generates an acid upon heating or exposing to light.
- the acid generator contained in the composition enables occurrence of an acid within the composition upon heating, regardless of the acid catalyst diffused from the photoresist pattern.
- the acid quencher eliminates the acid catalyst diffused from the photoresist pattern, thus controlling the rate of chemical reaction with the polymer in the coating film.
- the content of the acid diffuser, acid generator and acid quencher may be 0.1 to 100 parts by weight, based on the total weight of the polymer.
- the surfactant controls coatability and gap-filling property of the resin composition.
- the content of the surfactant may be 0.01 to 0.5 parts by weight, based on the total weight of the resin composition.
- a method for fabricating a semiconductor device by using the resin composition according to the present invention comprises the steps of: forming a first photoresist pattern containing an acid catalyst on a semiconductor substrate; coating the first photoresist pattern with the resin composition of the present invention to form a coating film; allowing the acid catalyst contained in the first photoresist pattern to be supplied to the coating film to make insoluble regions in the coating film; developing and stripping the coating film with a developing solvent to form a second photoresist pattern; and etching the semiconductor substrate using the second photoresist pattern as a mask.
- the photoresist that may be used in semiconductor device fabrication according to the present invention may be a KrF or ArF photoresist.
- the supply of acid catalyst from the first photoresist pattern may be promoted by heating the first photoresist pattern.
- the developing solvent may be water or an aqueous mixture of water-miscible solvent.
- An organic anti-reflective coating is coated on a silicon wafer.
- a photoresist is then coated thereon.
- the photoresist is exposed to light using exposure equipment, followed by developing, to form a line and space (L/S) pattern or a hole pattern.
- the resin composition is coated on the pattern to form a coating film.
- the coating film is heated to facilitate diffusion of an acid catalyst in the photoresist pattern. At this time, there arise removal reactions of water-soluble groups within the polymer contained in the coating film being in contact with the photoresist pattern. This mechanism is schematically shown FIG. 2.
- the acid catalyst within the photoresist pattern diffuses into the coating film.
- the acid catalyst induces a chemical reaction of the polymer in the coating film.
- insoluble regions exhibiting insolubility to a developing solvent are selectively left in the coating film.
- the heating temperature and time are determined by varying the kind of photoresist used and desired thickness of the insoluble regions in the coating film.
- Example 1 An organic anti-reflective coating was coated on a silicon wafer, and a KrF photoresist was coated thereon. The resulting structure was subjected to exposure to light using exposure equipment (ASML, XT: 1,400, NA 0.93), followed by developing. A substrate bearing an L/S pattern with 200 nm of an initial critical dimension (CD ) was obtained.
- the photoresist was developed by dipping in water for 1 min.
- the critical dimension (CD ) of the substrate was measured using a field emission scanning electron microsope (FE-SEM). The result is shown in Table 1.
- Example 2 A substrate was produced in the same manner as in Example 1, except that the heating was conducted at 13O 0 C. The critical dimension (CD ) of the produced substrate was measured. The result is shown in Table 1.
- Example 3 A substrate was produced in the same manner as in Example 1, except that the heating was conducted at 15O 0 C. The critical dimension (CD ) of the produced substrate was measured. The result is shown in Table 1.
- a KrF photoresist was used as a photoresist material.
- the present invention is not limited to the photoresist material.
- an L/S pattern was used as a photoresist pattern.
- the present invention is not limited to the pattern and is applicable to various patterns including a hole pattern.
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Architecture (AREA)
- Structural Engineering (AREA)
- Materials For Photolithography (AREA)
- Photosensitive Polymer And Photoresist Processing (AREA)
Abstract
Disclosed herein is a resin composition for forming fine patterns that enables reduction in width of an engraved portion in a photoresist pattern during lithography in semiconductor device fabrication. Further, disclosed herein is a method for fabricating a semiconductor device by using the composition. The resin composition comprises a) a polymer having aromatic hydroxyl groups in which all or a part of the hydroxyl groups are substituted with a water-soluble group; and b) water or an aqueous mixture of water-miscible solvent wherein the composition is applied to a photoresist pattern to form a coating film and the water-soluble group is removed by an acid catalyst supplied from the photoresist pattern, to selectively leave insoluble regions in the coating film.
Description
Description
RESIN COMPOSITION FOR FORMING FINE PATTERNS,
METHOD FOR FABRICATING SEMICONDUCTOR DEVICE
USING THE COMPOSITION AND SEMICONDUCTOR DEVICE
FABRICATED BY THE METHOD Technical Field
[1] The present invention relates to a resin composition for forming fine patterns that enables reduction in width of an engraved portion in a photoresist pattern during lithography in semiconductor device fabrication and a method for fabricating a semiconductor device by using the composition.
[2]
Background Art
[3] In the microelectronics industry as well as in other industries associated with microscopic structures (e.g., micromachines, magnetoresistive heads, etc.), there has been continuous demand for reduction in size of structures. In particular, in the microelectronics industry, there has been demand to provide greater amount of circuitry in a chip having a predetermined size based on the reduction in feature size of microelectronic devices.
[4] Lithographic techniques are essential for obtaining reduction in sizes of patterns. The manufacture of microscopic structures in lithography must be made in view of not only directly imaging patterns on a substrate, but also producing masks used in such imaging.
[5] Typical lithographic processes involve formation of a patterned resist layer by patternwise exposing a radiation- sensitive resist to an imaging radiation. The image is subsequently developed by contacting the exposed resist layer with a material (typically an aqueous alkaline developer) to selectively remove portions of the resist layer to reveal the desired pattern. The pattern is subsequently transferred to an underlying material by etching the material in openings of the patterned resist layer. After the transfer is complete, the remaining resist layer is removed.
[6] Lithographic techniques require irradiation with light of shorter wavelength and development of high-resolution resist materials depending on the characteristics of the light. However, improvements of exposure systems are needed to shorten the wavelength of light, thus incurring considerable costs. In addition, it is not easy to develop resist materials in response to short-wavelength light for exposure.
[7] In particular, conventional lithographic techniques have limitations in improving the
degree of integration through micropatterning due to limited wavelength of light for exposure. Some attempts to overcome these limitations have been proposed. For example, Japanese Patent No. 3,071,401 suggests a micropattern-forming material which uses a water-soluble resin causing a crosslinking reaction with a resist in the presence of an acid to form a crosslinked film at the interface between a resist pattern and the micropattern-forming material by the acid supplied from the resist pattern and to strip the uncrosslinked portions.
[8] However, when the material is used to form a pattern, the resist pattern may be deformed by the action of an internal stress resulting from volume shrinkage of the resin during the crosslinking reaction. There is thus a demand for a micropattern- forming material with a new type of mechanism that is capable of overcoming the limitations of conventional materials utilizing crosslinking mechanisms.
[9]
Disclosure of Invention Technical Problem
[10] In an attempt to solve the problems of prior arts, it is one object of the present invention to provide a resin composition for forming fine patterns with a new type of mechanism that enables formation of fine patterns without limitation in wavelength of exposure light sources.
[11] It is another object of the present invention to provide a method for fabricating a semiconductor device using the resin composition.
[12] It is yet another object of the present invention to provide a semiconductor device fabricated by the method.
[13]
Technical Solution
[14] In accordance with one aspect of the present invention, there is provided a resin composition for forming fine patterns, the resin composition comprising: a) a polymer having aromatic hydroxyl groups in which all or a part of the hydroxyl groups are substituted with a water-soluble group; and b) water or an aqueous mixture of water- miscible solvent whereby the composition is applied to a photoresist pattern to form a coating film and the water-soluble group is removed by an acid catalyst supplied from the photoresist pattern, to selectively make insoluble regions in the coating film.
[15] The polymer may be a novolac-type polymer, hydroxystyrene-type polymer or naphtol-type polymer, or a mixture thereof in which all or a part of the hydroxyl groups of the aromatic rings are substituted with a water-soluble group.
[16] The water-soluble group may be at least one selected from the group consisting of carbohydrates, nucleic acids, proteins, amino acids, ketones having an amine or
hydroxyl group, aldehydes having an amine or hydroxyl group, and derivatives thereof.
[17] The polymer may be represented by Formula 1 below:
(1)
[19] wherein the ratio n/m is 0 to 999 and the sum n+m is 2 to 30,000.
[20] The composition may comprise 1 to 50 parts by weight of the polymer and 50 to 99 parts by weight of the solvent.
[21] The composition may further comprise at least one additive selected from acid diffusers, acid generators, acid quenchers and surfactants.
[22] In accordance with another aspect of the present invention, there is provided a method for fabricating a semiconductor device, the method comprising the steps of: forming a first photoresist pattern containing an acid catalyst on a semiconductor substrate; coating the first photoresist pattern with the resin composition to form a coating film; allowing the acid catalyst contained in the first photoresist to be supplied to the coating film to make insoluble regions in the coating film; developing and stripping the coating film with a developing solvent to form a second photoresist pattern; and etching the semiconductor substrate using the second photoresist pattern as a mask.
[23] The supply of acid catalyst from the first photoresist pattern may be promoted by heating the first photoresist pattern.
[24] The developing solvent may be water or an aqueous mixture of water-miscible solvent.
[25] In accordance with yet another aspect of the present invention, there is provided a semiconductor device fabricated by the method.
[26]
Advantageous Effects
[27] According to the present invention, patterns can be formed without limitation of exposure light wavelength by using fine photoresist patterns.
[28] It is possible to reduce the size of an L/S or hole pattern. In addition, when a semiconductor device is fabricated using the fine patterns as a mask, finer patterns can be achieved, as compared to patterns obtained from conventional exposure light sources.
[29] Accordingly, the use of the present invention enables formation of semiconductor devices including finer L/S and hole patterns. [30]
Brief Description of the Drawings
[31] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
[32] FIG. 1 is a diagram schematically showing a lithographic process using a resin composition for forming fine patterns according to the present invention; and
[33] FIG. 2 is a cross-sectional view illustrating a state in which a predetermined region insoluble in a developing solution is selectively formed in a coating film by a chemical reaction of a fine pattern forming resin composition contained in the coating film according to the present invention.
[34]
Best Mode for Carrying Out the Invention
[35] Detailed description will be made of preferred embodiments of the present invention with reference to the accompanying drawings. However, various changes and modifications may be made to the preferred embodiments of the invention and the invention is not to be construed as being limited to the embodiments.
[36] The resin composition of the present invention comprises a) a polymer having aromatic hydroxyl groups in which all or a part of the hydroxyl groups are substituted with a water-soluble group; and b) water or an aqueous mixture of water-miscible solvent.
[37] The polymer is preferably a novolac-type polymer, hydroxystyrene-type polymer or naphtol-type polymer, or a mixture thereof in which all or a part of the hydroxyl groups of the aromatic rings are substituted with a water-soluble group.
[38] The solvent contained in the resin composition must be capable of dissolving the polymer, but be incapable of dissolving a photoresist layer. Taking into consideration this fact, preferred is water or an aqueous mixture of water-miscible solvent.
[39] The examples of the water-soluble solvent include isopropyl alcohol, 1-butanol, ethanol and methanol. The ratio of water to the water-soluble solvent may be in the range of 1 : 99 to 99 : 1 (w/w).
[40] The water-soluble group is at least one selected from the group consisting of carbohydrates, nucleic acids, proteins, amino acids, ketones containing an amine or hydroxyl group, aldehydes containing an amine or hydroxyl group, and derivatives thereof.
[41] The resin composition may consist of 1 to 50 parts by weight of the polymer and 50
to 99 parts by weight of the solvent. The contents out of the range defined above disad- vantageously cause an excessively high or low viscosity upon spin coating, thus making it difficult to control a film thickness.
[42] After the resin composition is applied to on a photoresist pattern to form a coating film, when an acid catalyst present within the photoresist pattern is supplied into the coating film, water-soluble groups within the coating film are removed by the acid catalyst. As a result, predetermined regions insoluble in a developing solvent such as water or an aqueous mixture of water-miscible solvent are selectively produced in the coating film.
[43] In this case, the acid catalyst diffused from the photoresist pattern is supplied into the coating film. Thus, removal reactions of water-soluble groups selectively occur in predetermined regions being in contact with the photoresist pattern and in regions to which the diffusing acid catalyst can reach. The moieties, where the water-soluble groups are removed, become insoluble in the solvent. The coating film includes both soluble and insoluble regions in developing solvents, thus achieving a selective solubility to the developing solvents.
[44] Accordingly, when the resin composition is used during a lithographic process in semiconductor device fabrication, the unreacted portions of the coating film are dissolved in and stripped by the developing solvent having a selective solubility dependent upon chemical reaction of the resin composition of coating film, thereby enabling reduction in width of an engraved portion of photoresist pattern.
[45] As the polymer contained in the resin composition, there may be used a polymer represented by Formula 1 below:
(1)
[47] wherein the ratio n/m is 0 to 999 and the sum n+m is 2 to 30,000.
[48] The n/m value of zero indicates that hydroxyl groups of side chain aromatic groups in polyhydroxystyrene are completely substituted with glucose groups. Meanwhile, the n/m value exceeding 999 disadvantageously involves considerable reduction in solubility to the solvent of the present invention. [49] The glucose group of the polymer represented by Formula 1 is removed in the presence of an acid catalyst to generate polyhydroxystyrene represented by Formula 2
below:
(2)
[51] wherein n is 2 to 30,000
[52] The polyhydroxystyrene is insoluble in the developing solvent used to develop the coating film which is formed by coating a photoresist pattern with the resin composition of the present invention. Accordingly, after the removal of glucose groups in the presence of an acid catalyst, predetermined regions insoluble in the developing solution are made in the coating film. At this time, the acid catalyst from the photoresist pattern is diffused into the coating film. Thus, the removal reaction of water-soluble groups selectively occurs in predetermined regions of the coating film being in contact with the photoresist pattern and in regions to which the diffusing acid catalyst can reach. The moieties, in which the water-soluble groups are removed, become insoluble in the solvent. The coating film includes both soluble regions and insoluble regions, thus achieving a selective solubility.
[53] The resin composition may further comprise at least one selected from acid diffusers, acid generators, acid quenchers and surfactants.
[54] The acid diffuser elevates a diffusion ratio of acid which is supplied from a photoresist pattern to the coating film including the resin composition and enables the chemical reaction of polymer to occur from the surface of the coating to a larger depth thereof. As a result, the width of the engraved portion of photoresist pattern is reduced, thus achieving fine patterns.
[55] The acid generator generates an acid upon heating or exposing to light. The acid generator contained in the composition enables occurrence of an acid within the composition upon heating, regardless of the acid catalyst diffused from the photoresist pattern.
[56] The acid quencher eliminates the acid catalyst diffused from the photoresist pattern, thus controlling the rate of chemical reaction with the polymer in the coating film.
[57] The content of the acid diffuser, acid generator and acid quencher may be 0.1 to 100 parts by weight, based on the total weight of the polymer.
[58] The surfactant controls coatability and gap-filling property of the resin composition.
[59] The content of the surfactant may be 0.01 to 0.5 parts by weight, based on the total
weight of the resin composition.
[60] A method for fabricating a semiconductor device by using the resin composition according to the present invention comprises the steps of: forming a first photoresist pattern containing an acid catalyst on a semiconductor substrate; coating the first photoresist pattern with the resin composition of the present invention to form a coating film; allowing the acid catalyst contained in the first photoresist pattern to be supplied to the coating film to make insoluble regions in the coating film; developing and stripping the coating film with a developing solvent to form a second photoresist pattern; and etching the semiconductor substrate using the second photoresist pattern as a mask.
[61] The photoresist that may be used in semiconductor device fabrication according to the present invention may be a KrF or ArF photoresist.
[62] The supply of acid catalyst from the first photoresist pattern may be promoted by heating the first photoresist pattern.
[63] The developing solvent may be water or an aqueous mixture of water-miscible solvent.
[64] A lithographic process to form fine patterns by using the resin composition according to the present invention will be described in detail as follows.
[65] An organic anti-reflective coating is coated on a silicon wafer. A photoresist is then coated thereon. The photoresist is exposed to light using exposure equipment, followed by developing, to form a line and space (L/S) pattern or a hole pattern. The resin composition is coated on the pattern to form a coating film. The coating film is heated to facilitate diffusion of an acid catalyst in the photoresist pattern. At this time, there arise removal reactions of water-soluble groups within the polymer contained in the coating film being in contact with the photoresist pattern. This mechanism is schematically shown FIG. 2.
[66] That is, when the resin composition is coated on the photoresist pattern formed on the semiconductor substrate, followed by heating, the acid catalyst within the photoresist pattern diffuses into the coating film. The acid catalyst induces a chemical reaction of the polymer in the coating film. As a result, insoluble regions exhibiting insolubility to a developing solvent are selectively left in the coating film. At this time, the heating temperature and time are determined by varying the kind of photoresist used and desired thickness of the insoluble regions in the coating film.
[67] The unreacted portions of coating film are dissolved in the developing solvent, followed by stripping, to form a second photoresist pattern having a reduced width of engraved portion.
[68]
Mode for the Invention
[69] The present invention will be better understood from the following examples. These examples are not to be construed as limiting the scope of the invention.
[70] [71] EXAMPLES [72] Synthesis Example [73] 10 g of polyhydroxystyrene (available from Dupont), 45 g of 2,3,4,6-tetra-O-acetyl-mannopyranosyl-trichloroacetimidate, 2 g of trimethylsi- lyltriflate, 5 g of 0.4 nm molecular sieve and 300 mL of acetonitrile were put in a flask of 500 mL. Then, the mixture was stirred at O0C for 2 hours. Triethylamine was added thereto, thereby neutralizing the solution. After the temperature was allowed to warm to room temperature, the solvent was evaporated, and was distilled using a vacuum distiller. The residues was purified by chromatography (methylenechloride and methanol (2 : I)). The solvents were distilled off under reduced pressure, and dried under vacuum to yield a polymer (n/m = 1.1, weight average molecular weight: 18,000, 35.5 g) represent by Formula 3 below:
(3)
[75] Next, 20 g of the polymer of Formula 3 was put in a flask of 500 mL, and was dissolved in 300 mL of tetrahydrofuran (THF). A 25% solution of sodium methanolate (NaOMe) in methanol (MeOH) was added thereto. After stirring at O0C for 2 hours, the reaction mixture was filtered under reduced pressure. The obtained solid was washed twice with THF and was dried under vacuum to yield a polymer (n/m = 1.1, 12.0 g) represent by Formula 1 below:
(1)
[77] [78] Example 1 [79] An organic anti-reflective coating was coated on a silicon wafer, and a KrF photoresist was coated thereon. The resulting structure was subjected to exposure to light using exposure equipment (ASML, XT: 1,400, NA 0.93), followed by developing. A substrate bearing an L/S pattern with 200 nm of an initial critical dimension (CD ) was obtained.
[80] Next, a resin composition comprising 10 g of the polymer prepared in Synthesis Example and 90 g of water was coated on the pattern, followed by heating at 11O0C for 1 min.
[81] The photoresist was developed by dipping in water for 1 min. The critical dimension (CD ) of the substrate was measured using a field emission scanning electron microsope (FE-SEM). The result is shown in Table 1.
[82] [83] Example 2 [84] A substrate was produced in the same manner as in Example 1, except that the heating was conducted at 13O0C. The critical dimension (CD ) of the produced substrate was measured. The result is shown in Table 1.
[85] [86] Example 3 [87] A substrate was produced in the same manner as in Example 1, except that the heating was conducted at 15O0C. The critical dimension (CD ) of the produced substrate was measured. The result is shown in Table 1.
[88] Table 1 [Table 1] [Table ]
[89] [90] From Table 1, it could be confirmed that the resin composition of the present invention enables considerable reduction in width of the ungraved portion in photoresist pattern.
[91] In Examples of the present invention, a KrF photoresist was used as a photoresist material. However, the present invention is not limited to the photoresist material.
Meanwhile, an L/S pattern was used as a photoresist pattern. However, the present invention is not limited to the pattern and is applicable to various patterns including a hole pattern.
[92] Although the present invention has been described herein in detail with reference to its preferred embodiments, those skilled in the art will appreciate that these embodiments do not serve to limit the invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.
[93]
Claims
[1] A resin composition for forming fine patterns, the resin composition comprising: a) a polymer having aromatic hydroxyl groups in which all or a part of the hydroxyl groups are substituted with a water-soluble group; and b) water or an aqueous mixture of water-miscible solvent whereby the composition is applied to a photoresist pattern to form a coating film and the water-soluble group is removed by an acid catalyst supplied from the photoresist pattern, to selectively make insoluble regions in the coating film.
[2] The composition according to claim 1, wherein the polymer is a novolac-type polymer, hydroxystyrene-type polymer or naphtol-type polymer, or a mixture thereof in which all or a part of the hydroxyl groups of the aromatic rings are substituted with a water-soluble group.
[3] The composition according to claim 1, wherein the water-soluble group is at least one selected from the group consisting of carbohydrates, nucleic acids, proteins, amino acids, ketones having an amine or hydroxyl group, aldehydes having an amine or hydroxyl group, and derivatives thereof.
[4] The composition according to claim 1, wherein the polymer is represented by
Formula 1 below:
(1) wherein the ratio n/m is 0 to 999 and the sum n+m is 2 to 30,000. [5] The composition according to claim 1, wherein the composition comprises 1 to
50 parts by weight of the polymer and 50 to 99 parts by weight of the solvent. [6] The composition according to claim 1, further comprising at least one additive selected from acid diffusers, acid generators, acid quenchers and surfactants. [7] A method for fabricating a semiconductor device, the method comprising the steps of: forming a first photoresist pattern containing an acid catalyst on a semiconductor substrate; coating the first photoresist pattern with the resin composition according to any one of claims 1 to 6 to form a coating film;
allowing the acid catalyst contained in the first photoresist to be supplied to the coating film to make insoluble regions in the coating film; developing and stripping the coating film with a developing solvent to form a second photoresist pattern; and etching the semiconductor substrate using the second photoresist pattern as a mask. [8] The method according to claim 7, wherein the supply of the acid catalyst from the first photoresist pattern is promoted by heating the first photoresist pattern. [9] The method according to claim 7, wherein the developing solvent is water or an aqueous mixture of water-miscible solvent. [10] A semiconductor device fabricated by the method according to claim 7.
Applications Claiming Priority (2)
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KR1020060076027A KR20080014388A (en) | 2006-08-11 | 2006-08-11 | Hardmask composition making unsoluble polymers to developing solution, process of producing semiconductor devices using the same and semiconductor devices produced by the process |
KR10-2006-0076027 | 2006-08-11 |
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WO2008018749A1 true WO2008018749A1 (en) | 2008-02-14 |
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PCT/KR2007/003809 WO2008018749A1 (en) | 2006-08-11 | 2007-08-08 | Resin composition for forming fine patterns, method for fabricating semiconductor device using the composition and semiconductor device fabricated by the method |
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Cited By (2)
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CN103823331A (en) * | 2012-10-31 | 2014-05-28 | 罗门哈斯电子材料有限公司 | Photoresists comprising ionic compound |
EP4092039A1 (en) * | 2021-05-20 | 2022-11-23 | Samsung Electronics Co., Ltd. | Polypeptide, photoresist composition including the same, and method of forming pattern using the same |
Families Citing this family (3)
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KR101742815B1 (en) | 2010-07-23 | 2017-06-01 | 삼성전자 주식회사 | Coating composition for DUV filtering, method of forming a photoresist pattern using the same and method of fabricating a semiconductor device |
JP6182381B2 (en) | 2013-07-29 | 2017-08-16 | 信越化学工業株式会社 | Resist protective film material and pattern forming method |
US9804493B2 (en) | 2013-11-22 | 2017-10-31 | Samsung Electronics Co., Ltd. | Composition for forming topcoat layer and resist pattern formation method employing the same |
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US20030175624A1 (en) * | 2001-08-10 | 2003-09-18 | Fujitsu Limited | Resist pattern swelling material, and method for patterning using same |
US20040029047A1 (en) * | 2002-08-07 | 2004-02-12 | Renesas Technology Corp. | Micropattern forming material, micropattern forming method and method for manufacturing semiconductor device |
US20040072098A1 (en) * | 2002-09-30 | 2004-04-15 | Fujitsu Limited | Resist pattern thickening material, process for forming resist pattern, and process for manufacturing semiconductor device |
US20040121259A1 (en) * | 2002-08-21 | 2004-06-24 | Fujiitsu Limited | Resist pattern thickening material, process for forming resist pattern, and process for manufacturing semiconductor device |
-
2006
- 2006-08-11 KR KR1020060076027A patent/KR20080014388A/en not_active Application Discontinuation
-
2007
- 2007-08-08 WO PCT/KR2007/003809 patent/WO2008018749A1/en active Application Filing
- 2007-08-10 TW TW96129631A patent/TW200815927A/en unknown
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030175624A1 (en) * | 2001-08-10 | 2003-09-18 | Fujitsu Limited | Resist pattern swelling material, and method for patterning using same |
US20040029047A1 (en) * | 2002-08-07 | 2004-02-12 | Renesas Technology Corp. | Micropattern forming material, micropattern forming method and method for manufacturing semiconductor device |
US20040121259A1 (en) * | 2002-08-21 | 2004-06-24 | Fujiitsu Limited | Resist pattern thickening material, process for forming resist pattern, and process for manufacturing semiconductor device |
US20040072098A1 (en) * | 2002-09-30 | 2004-04-15 | Fujitsu Limited | Resist pattern thickening material, process for forming resist pattern, and process for manufacturing semiconductor device |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103823331A (en) * | 2012-10-31 | 2014-05-28 | 罗门哈斯电子材料有限公司 | Photoresists comprising ionic compound |
EP4092039A1 (en) * | 2021-05-20 | 2022-11-23 | Samsung Electronics Co., Ltd. | Polypeptide, photoresist composition including the same, and method of forming pattern using the same |
US12024540B2 (en) | 2021-05-20 | 2024-07-02 | Samsung Electronics Co., Ltd. | Polypetide, photoresist composition including the same, and method of forming pattern using the same |
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TW200815927A (en) | 2008-04-01 |
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