JP4098128B2 - Photosensitive composition and method for curing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention provides a method for forming a fine pattern on a semiconductor substrate.PhotosensitivityThe present invention relates to a composition and a curing method thereof.
[0002]
[Prior art]
  When forming a pattern in a semiconductor integrated device typified by a VLSI, it is sensitive to high energy rays such as ultraviolet rays, X-rays, and electron beams on the substrate.PhotosensitivityIn general, a thin film made of the composition is formed, and this is irradiated with a high energy ray and then developed.
  Figure 3 shows the conventionalPhotosensitivityIt is a figure explaining the fine pattern formation process using a composition. In this fine pattern formation process, first, as shown in FIG. 3A, the silicon substrate 1 on which the resist film 2 is formed is irradiated with a high energy ray from the resist film 2 side, developed, and then developed as shown in FIG. As shown in b), a resist pattern 4a is formed. Next, as shown in FIG. 3C, the reactive gas 6 is reacted with the resist film 2, and as shown in FIG. 3D, the resist film 2 is removed to form a fine pattern 4b.
  In such a pattern formation process, a resist film is formed from the viewpoint of rapid pattern formation processing.PhotosensitivityIn addition to being sensitive to the composition, it is required to be sensitive to high energy rays (high pattern resolution) and to have high resistance to reactive gases. .
[0003]
  The pattern resolution generally improves as the resist film becomes thinner because the spread of high energy rays in the resist film becomes smaller. Therefore, in order to improve the pattern resolution and pattern accuracy, it is necessary to make the resist film as thin as possible. Also, in the research and development of advanced devices such as next-generation VLSI and quantum effect elements, the pattern dimension will be in the nanometer region of 100 nm or less, and in terms of further miniaturization and higher precision, the resist film will become increasingly thinner. Desired.
  By the way, since the miniaturization and the thinning of the resist have been performed at the same time as described above, the ratio of the resist film thickness to the pattern dimension (usually referred to as the aspect ratio) has been an almost constant value in the range of 3 to 5 so far. This is expected to continue in the future. Therefore, assuming that the aspect ratio is 4, for example, when the pattern dimension is 100 nm, the resist film thickness must be 400 nm. When the pattern dimension is 50 nm, the resist film thickness is 200 nm. When the pattern dimension is 10 nm, the resist film thickness is 200 nm. The film thickness is 40 nm. That is, the resist film is expected to be an ultrathin film as described above.
[0004]
  Conventionally, as a resist material used for forming a fine pattern, the following three types are mainly listed.
(1) Acrylic resin resist.
(2) A resist having an alkali-soluble resin and a photosensitizer.
(3) A chemically amplified resist having an alkali-soluble resin, an acid generator, and a solubility control agent having an acid labile group.
[0005]
  (1) Acrylic resin resist is a resist that is used to form fine patterns in the nanometer region. The main chain of acrylic polymer is cut by irradiation with ultraviolet rays, X-rays, and electron beams to lower the molecular weight and dissolve. The pattern is formed by improving the property and developing with a developer. As typical materials of this type of resist, for example, polymethyl methacrylate (PMMA), a ZEP resist (manufactured by Zeon Corporation) which is a copolymer of methyl α-chloroacrylate and α-methylstyrene, poly 2, Examples include 2,2-trifluoroethyl α-chloroacrylate (EBR-9, manufactured by Toray Industries, Inc.).
[0006]
  (2) A resist having an alkali-soluble resin and a photosensitive agent is a resist material for ultraviolet exposure that is widely used in the production of LSIs and liquid crystals, and a diazonaphthoquinone compound is mainly used as the photosensitive agent. The photosensitive agent is also a solubility control agent (alkali insoluble), becomes alkali-soluble by irradiation with high energy rays, and forms a pattern by developing with an alkali developer. On the other hand, as the alkali-soluble resin, for example, novolak resin, phenol resin, polyhydroxystyrene, or the like is used.
[0007]
  (3) Chemical amplification type resists having an alkali-soluble resin, an acid generator, and a solubility control agent having an acid labile group have recently been put to practical use as LSIs for high sensitivity and high resolution. . The pattern formation by alkali development is the same as (2), but the acid generated from the acid generator by high energy ray irradiation acts as a catalyst to chemically change the solubility control agent having an acid labile group in a chain reaction. To make it highly sensitive. As the alkali-soluble resin, those similar to (2) can be used, and an acrylic resin having high transparency to high energy rays has been developed.
[0008]
  However, further thinning of the resist film using the above three types of resists is limited because the dry etching resistance during substrate processing is not sufficient. That is, in the conventional resist, if the resist film thickness is extremely thin, the resistance of the resist film to the reactive gas 6 becomes insufficient during dry etching with the reactive gas 6 as shown in FIG. As shown in FIG. 3D, defects 7, 7,... May occur in the silicon substrate 1.
[0009]
  Therefore, in recent years, as a technology that amplifies dry etching resistance and enables further resist thinning, a composite in which fine particles containing a highly resistant carbon atom aggregate as a main component are added to the above resist material. A resist has been proposed (Patent Document 1). Furthermore, an example using one or both of fullerene and fullerene derivatives as the fine particles has been reported. For example, in Non-Patent Document 1, a mixture of fullerenes C60 and C70 is combined with a ZEP resist.PhotosensitivityA composition is described. In this technique, a 150 nm resist thin film is irradiated with an electron beam to form a 50 nm pattern, and the substrate is processed by dry etching using a halogen gas.
[0010]
[Patent Document 1]
JP-A-10-282649
[Non-Patent Document 1]
  Japanese Journal Applied Physics (Jpn. J. Appl. Phys), Vol. 36, No. 12B, pages 7642-7645 (1997)
[0011]
[Problems to be solved by the invention]
  However, even with the above-mentioned fullerene composite resist, when the film thickness is further reduced, defects may occur in the silicon substrate. Specifically, since the limit of the resist film thickness based on etching resistance is about 100 nm, it is difficult to form a pattern with a dimension of 25 nm or less without causing defects in the substrate when the aspect ratio is set to 4. there were.
  The object of the present invention is to prevent the formation of defects in the substrate and to process the substrate with high precision even when the resist film is further thinned in the formation of a fine pattern such as a semiconductor substrate.PhotosensitivityIt is to provide a composition and a method for curing the composition.
[0012]
[Means for Solving the Problems]
  Claim 1 of the present applicationofPhotosensitivityThe composition has a resist, fine particles composed of one or both of fullerene and a fullerene derivative, and a crosslinking agent.The crosslinking agent is borazine or a borazole derivative.It is characterized by that.
  In the photosensitive composition of claim 1 of the present application,Furthermore, the crosslinking agent is at least one selected from an amino compound, an azide compound, a diazo compound, and a hydroxyl group-containing compound.IncludingAlso good.
  In addition, the present inventionPhotosensitivityIn the composition, the resist may be an acrylic resin resist.
  Alternatively, the resist may have an alkali-soluble resin and a photosensitive agent.
  The photosensitive composition of claim 5 comprises a resist, fine particles comprising one or both of fullerene and a fullerene derivative, and a crosslinking agent. The resist comprises an alkali-soluble resin, an acid generator, It is a chemically amplified resist having a solubility control agent having an acid labile group.
  In the photosensitive composition according to claim 5 of the present application, the crosslinking agent is preferably borazine or a borazole derivative. The cross-linking agent may further contain at least one selected from an amino compound, an azide compound, a diazo compound, and a hydroxyl group-containing compound.
  Of the present inventionPhotosensitivityThe method of curing the composition has been described above.PhotosensitivityThe composition is characterized by irradiating the composition with high energy rays to form a chemical bond between at least two of the resist, the fine particles comprising one or both of fullerene and fullerene derivative, and the crosslinking agent.
[0013]
  Of the present inventionPhotosensitivitySince the composition contains a cross-linking agent, the fine particles comprising one or both of fullerene and fullerene derivative can be cross-linked when the resist pattern is irradiated with high energy rays such as ultraviolet rays. As a result, since a three-dimensional stitch structure can be formed, the resist film can be strengthened.
  That is, fine particles made of one or both of fullerene and a fullerene derivative can be made into a cross-linked structure so as to have higher resistance than a resist film containing only fine particles. Therefore, the resist film can be further thinned, and further miniaturization of the pattern and higher accuracy can be realized.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
  Of the present inventionPhotosensitivityThe composition includes a resist, fine particles (hereinafter abbreviated as fine particles) made of one or both of fullerene and a fullerene derivative, and a crosslinking agent.
  The resist includes (1) an acrylic resin resist, (2) a resist having an alkali-soluble resin and a photosensitizer, and (3) a solubility control agent having an alkali-soluble resin, an acid generator, and an acid labile group. A chemically amplified resist having the following can be used. These are the same as those listed in the section of the prior art.
[0015]
  In the fullerene constituting the fine particles, carbon atoms have a spherical shell molecular structure, and C₆₀(Fullerene 60), C_{7 0}There are various forms called fullerenes including (fullerene 70). Examples of fullerenes include higher-order fullerenes having 60 or more carbon atoms, nanotubes that are long in the shape of a cylinder, and metal-encapsulated fullerenes in which a metal is incorporated into its spherical shell molecular structure. . Among these fullerenes, those having a molecular volume as small as possible are preferable from the viewpoint of improving resistance and resolution by increasing density.
  When using a higher-order fullerene having 60 or more carbon atoms or a derivative thereof, a plurality of types of fullerenes may be mixed. For example, fullerene 60 and fullerene 70 may be mixed. When mixed in this way, the separation operation after fullerene synthesis can be omitted, which is efficient.
[0016]
  As the fine particles, a fullerene derivative in which an atom such as hydrogen, a functional group such as a methyl group, an amino group, or the like is bonded to the carbon atom of fullerene can be used.PhotosensitivityIt is effective in filling the voids of the composition and increasing the etching resistance. Any fullerene derivative can be used, but from the viewpoint of improving resistance and resolution by increasing the density, a functional group that has a molecular volume as small as possible and that can be dissolved in a coating solvent for conventional resists. What you have is most suitable. Among these, a fullerene derivative having an amino group is preferable from the viewpoint of promoting a crosslinking reaction.
  Further, fullerenes and fullerene derivatives may be used in combination.
[0017]
  PhotosensitivityThe content of fine particles in the composition is preferably 1 to 50% by mass. When the content of the fine particles is less than 1% by mass, the resistance may not be sufficiently improved. When the content exceeds 50% by mass, the content of the resist is decreased, and thus the resist film may not function sufficiently.
[0018]
  The crosslinking agent has a plurality of functional groups (atomic groups that react by the action of light, heat, etc.) in order to form a three-dimensional stitch structure. Among such crosslinking agents, fullerene derivatives are preferred because they can easily form a crosslinked structure. In addition, the fullerene derivative can play a role as a crosslinking agent as well as a fine particle.
  It is also preferable to use borazine or a borazole derivative as a crosslinking agent. Borazine or borazole derivatives are highly resistant and heat resistant materials, as reported in, for example, Materials Research Society, 2002 Spring Meeting, Abstract, B 7.16, By using a compound having a functional group, it can be easily subjected to an addition reaction to fullerene, resist molecules or the like in the same manner as the fullerene derivative, and the resist film can be strengthened.
[0019]
  Moreover, at least 1 sort (s) chosen from an amino compound, an azide compound, a diazo compound, and a hydroxyl-containing compound can also be used as a crosslinking agent. These can be used in combination with borazine, a borazole derivative, or a fullerene derivative, or can be used alone.
  Examples of the amino compound that can be used as the crosslinking agent include those having two amino groups such as 4,4′-methylenebis (2-methylcyclohexylamine). Examples of the azide compound include 2,6-di- Examples thereof include those having two azido groups such as-(4'-azidocinnamylidene) -cyclohexanone.
[0020]
  The crosslinking reaction between the fine particles and the crosslinking agent can utilize addition reaction of functional groups to the carbon double bonds when the carbon double bonds are included in the fine particles. That is, when an amino compound, an azide compound, a diazo compound, or a hydroxyl group-containing compound is used as a crosslinking agent, the above compound is easily added to fine particles containing a carbon double bond by the action of light or heat to form a crosslinked structure. be able to.
  The crosslinking reaction between the fine particles and the crosslinking agent is generally induced by the action of heat or light, but it is preferable in terms of the processing process to be performed under relatively mild conditions so as not to damage the resist film and the substrate.
[0021]
  In addition, with respect to a method of adding an amino compound, azide compound, diazo compound, or hydroxyl group-containing compound as a crosslinking agent to fullerene or a fullerene derivative, for example, the Chemical Society of Japan, Chemical Review, Vol. 43, “Fullerene Chemistry”, (1999) and detailed reaction examples of fullerenes with amino compounds, azide compounds, diazo compounds and the like.
  In addition, as an addition method by photoreaction of fullerene and an amino compound, for example, as described in Chemical Communications, page 1423 (1996), an amino compound is additionally bonded to fullerene by irradiation with 350 nm ultraviolet rays. be able to.
[0022]
  PhotosensitivityIt is preferable that content of the crosslinking agent in a composition is 1-50 mass%. If the content of the cross-linking agent is less than 1% by mass, a three-dimensional network structure may not be formed sufficiently. If the content exceeds 50% by mass, the resist content decreases, so that it functions sufficiently as a resist film. There is a risk of not.
[0023]
  like thisPhotosensitivityTo cure the composition:PhotosensitivityThe composition is irradiated with high-energy rays such as ultraviolet rays, X-rays, and electron beams, and chemically bonded between at least two of the resist, fine particles comprising one or both of fullerene and fullerene derivatives, and a crosslinking agent. To form. By such chemical bondsPhotosensitivityThe composition is cured.
[0024]
  Mentioned abovePhotosensitivityA method for forming a fine pattern using the composition will be described. First, as shown in FIG.PhotosensitivityA resist solution in which the composition is dissolved in a solvent is applied and heat-treated to form a resist film 2 on the silicon substrate 1. Thereafter, the resist film 2 is irradiated with the high energy beam 3 using a high energy beam irradiation means such as an electron beam exposure apparatus.
  Next, as shown in FIG. 1B, a development process using a developer or the like is performed on the resist film 2 irradiated with the high energy beam 3 to remove the irradiated region, and a fine pattern is formed on the resist film 2. 4a is formed.
  Next, as shown in FIG. 1C, second high energy rays such as ultraviolet rays having a wavelength of 365 nm, ultraviolet rays in other wavelength regions, electron beams, and ion beams are formed on the resist film 2 on which the fine pattern 4a is formed. 5 is irradiated on the entire surface. Then, the fine particles 10 and the cross-linking agent 20 are reacted to form a cross-linking bond 30 and cure the resist film 2 as shown in FIG. At that time, the resist molecules and the crosslinking agent 20a can be crosslinked. When the resist molecules are cross-linked by a cross-linking agent and cured, the resist film becomes stronger. Note that heat can be applied to the resist film 2 in order to accelerate the curing reaction during crosslinking.
  Next, as shown in FIG. 1D, the silicon substrate 1 is dry-etched using the resist film 2 cured using the reactive gas 6 as a mask, and as shown in FIG. Based on the fine pattern 4 a of the film 2, the fine pattern 4 b can be formed on the substrate 1.
[0025]
  Explained abovePhotosensitivityThe composition has a resist, fine particles, and a cross-linking agent, and can form a three-dimensional stitch structure by chemically bonding the fine particles and the cross-linking agent using a general chemical reaction. As a result, since the resist thin film can be strengthened, the formation of defects in the substrate can be prevented even if the film thickness is further reduced. As a result, substrate processing can be performed with high accuracy, and nanometer processing can be realized.
[0026]
【Example】
  Examples of the present invention will be described below. The followingPhotosensitivityThe blending ratio of the composition shows an example, and the present invention is not limited to the following values, and can be flexibly changed according to the process conditions of the substrate processing.
[0027]
(referenceExample 1)
  A solvent containing ortho-dichlorobenzene as a main solvent, 10 parts by mass of fullerene C60 (fine particles) as fine particles and 10 parts by mass of a commercially available amino compound as a crosslinking agent, 4,4′-methylenebis (2-methylcyclohexylamine) Dissolved in. This solution is thenTypeMix with a ZEP resist solution containing 100 parts by weight of solid content of electron beam resist ZEP520,PhotosensitivityA resist solution containing the composition was prepared.
[0028]
  like thisPhotosensitivityUsing the composition, a fine pattern was formed on a silicon substrate as follows.
  First, as shown in FIG. 1A, a resist solution was spin-coated on a silicon substrate 1 and heat-treated to form a resist film 2 having a thickness of 50 nm on the silicon substrate 1. Then, the high energy beam 3 was irradiated to the resist film 2 using the electron beam exposure apparatus with an acceleration voltage of 100 kV.
  Next, as shown in FIG. 1B, a development process is performed on the resist film 2 irradiated with the high energy rays 3 using a commercially available developer for ZEP resist as a developer with a development time of 30 seconds. The irradiated region was removed, and a fine pattern 4 a having a dimension of about 15 nm was formed on the resist film 2.
  Next, as shown in FIG. 1C, the entire surface of the resist film 2 on which the fine pattern 4a is formed is irradiated with ultraviolet rays having a wavelength of 365 nm, which is the second high-energy beam 5, so that the fine particles 10 and the cross-linking agent 20a. As shown in FIG. 1D, a cross-linking bond 30 is formed and the resist film 2 is cured.
  Next, as shown in FIG.₂F₆The silicon substrate 1 is dry-etched using the resist film 2 cured by using a mask as a mask, and the fine pattern 4b is applied to the silicon substrate 1 based on the fine pattern 4a of the resist film 2 as shown in FIG. Formed.
[0029]
(referenceExample 2)
  Except for blending 10 parts by mass of fullerene C60 / C70 mixture (mixing ratio about 4/1) instead of 10 parts by mass of fullerene C60 as fine particles.referenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0030]
(referenceExample 3)
  Except for blending 10 parts by mass of fullerene derivative N- [4- (4'-phenoxy) phenyliminocarbonyl] phenylazafullerene (abbreviated name C60φOφ) instead of 10 parts by mass of fullerene C60 as fine particles.referenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
  Here, the fullerene C60 derivative C60φOφ is a method described in “Study on high-performance resist material by compounding fullerene derivatives” (Tetsuyoshi Ishii, Tokyo University of Agriculture and Technology, Graduate thesis, March 2001). Therefore, it was synthesized.
[0031]
(Example1)
  As a crosslinking agent, instead of 10 parts by mass of 4,4'-methylenebis (2-methylcyclohexylamine), borazine having a plurality of amino groups, 2- (phenylimino) -4,6-bis (p-aminophenylimino))Boraj(Abbreviated name PAB) Except for blending 10 parts by massreferenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
  Here, PAB was synthesized by the method described below. First, Inorg. Synth. 2,4,6-trichloroborazine (TCB) was synthesized by the method described in Journal, Vol. 10, page 139. Next, 1.83 g (10 mmol) of TCB was dissolved in 50 ml of acetonitrile, and a solution of 10 ml of acetonitrile in which 1.21 g (12 mmol) of triethylamine and 0.931 g (10 mmol) of aniline were dissolved was added dropwise thereto while stirring at 0 ° C. . Subsequently, after reacting at 0 ° C. for 6 hours, 2.42 g (24 mmol) of triethylamine and 5.41 g of p-phenylenediamine (50 mmol)lAnd a solution of 40 ml of acetonitrile dissolved therein was added dropwise at 0 ° C. with stirring. Subsequently, after reacting at 0 ° C. for 6 hours, the reaction was performed at room temperature for 6 hours, the precipitate was filtered, and then dried to dryness. Then, heat at about 80 ° C. under a reduced pressure of 1 mmHg or less,p-Phenylenediamine was removed by sublimation, and the residue was recrystallized from acetonitrile to obtain 1.25 g of PAB.
[0032]
(Example2)
  As a fine particle, instead of 10 parts by mass of fullerene C60, 10 parts by mass of a fullerene C60 / C70 mixture (mixing ratio of about 4/1) is blended, and 4,4′-methylenebis (2-methylcyclohexylamine) 10 as a crosslinking agent Example instead of parts by mass1Except for blending 10 parts by mass of borazine (PAB) used inreferenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0033]
(Example3)
  As fine particles, instead of 10 parts by mass of fullerene C60,reference10 parts by mass of the fullerene derivative C60φOφ used in Example 3 was blended, and instead of 10 parts by mass of 4,4′-methylenebis (2-methylcyclohexylamine) as a crosslinking agent, Example1Except that 10 parts by mass of borazine (PAB) used inreferenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0034]
(referenceExample4)
  As a crosslinking agent, instead of 10 parts by mass of 4,4′-methylenebis (2-methylcyclohexylamine), a commercially available azide compound having two azide groups, 2,6-di- (4′-azidocinnamylidene) ) Except that 10 parts by mass of cyclohexanone was blendedreferenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0035]
(referenceExample5)
  As fine particles, instead of 10 parts by mass of fullerene C60,reference10 parts by mass of the fullerene C60 / C70 mixture (mixing ratio: about 4/1) used in Example 2 was blended, and instead of 10 parts by mass of 4,4'-methylenebis (2-methylcyclohexylamine) as a crosslinking agent,referenceExample4Except that 10 parts by mass of the commercially available azide compound used in the above, 2,6-di- (4'-azidocinnamylidene) -cyclohexanone was blended.referenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0036]
(referenceExample6)
  As fine particles, instead of 10 parts by mass of fullerene C60,reference10 parts by mass of the fullerene derivative C60φOφ used in Example 3 was blended, and instead of 10 parts by mass of 4,4′-methylenebis (2-methylcyclohexylamine) as a crosslinking agent,referenceExample4Except that 10 parts by mass of the commercially available azide compound used in the above, 2,6-di- (4'-azidocinnamylidene) -cyclohexanone was blended.referenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0037]
(Example4)
  As a resist, positiveTypeExcept for using 100 mass parts of solid content of chemical amplification type resist for commercially available KrF excimer laser instead of 100 mass parts of solid content of electron beam resist ZEP520referenceSame as example 1PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0038]
(Example5)
  As a resist, positiveTypeExcept for using 100 mass parts of solid content of chemical amplification type resist for commercially available KrF excimer laser instead of 100 mass parts of solid content of electron beam resist ZEP520referenceSame as example 2PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0039]
(Example6)
  As a resist, positiveTypeInstead of 100 parts by mass of the solid content of electron beam resist ZEP520, 100 parts by mass of a commercially available KrF excimer laser chemically amplified resist is used, and fullerene derivative C60φOφ and 4,4′-methylenebis (2-methylcyclohexylamine). Is dissolved in propylene glycol monomethyl ether acetate (PGMEA) solventreferenceSame as example 3PhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0040]
(Example7)
  As a resist, positiveTypeExample in which 100 mass parts of solid content of chemical amplification system resist for commercially available KrF excimer laser was used instead of 100 mass parts of solid content of electron beam resist ZEP5201LikePhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0041]
(Example8)
  As a resist, positiveTypeExample in which 100 mass parts of solid content of chemical amplification system resist for commercially available KrF excimer laser was used instead of 100 mass parts of solid content of electron beam resist ZEP5202LikePhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0042]
(Example9)
  As a resist, positiveTypeExample in which 100 mass parts of solid content of chemical amplification system resist for commercially available KrF excimer laser was used instead of 100 mass parts of solid content of electron beam resist ZEP5203LikePhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0043]
Example 10)
  As a resist, positiveTypeExcept for using 100 mass parts of solid content of chemical amplification type resist for commercially available KrF excimer laser instead of 100 mass parts of solid content of electron beam resist ZEP520referenceExample4LikePhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0044]
Example 11)
  As a resist, positiveTypeExcept for using 100 mass parts of solid content of chemical amplification type resist for commercially available KrF excimer laser instead of 100 mass parts of solid content of electron beam resist ZEP520referenceExample5LikePhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0045]
Example 12)
  As a resist, positiveTypeExcept for using 100 mass parts of solid content of chemical amplification type resist for commercially available KrF excimer laser instead of 100 mass parts of solid content of electron beam resist ZEP520referenceExample6LikePhotosensitivityObtaining a composition,referenceIn the same manner as in Example 1, a fine pattern was formed on a silicon substrate.
[0046]
Example 13)
  As a resist, positiveTypeInstead of 100 parts by mass of the solid content of the electron beam resist ZEP520, 100 parts by mass of the solid content of a chemical amplification system resist for commercially available KrF excimer laser was used, and 10 parts by mass of 4,4′-methylenebis (2-methylcyclohexylamine) Instead, 10 parts by mass of a fullerene C60 derivative having a plurality of amino groups and bis [azidobenzoyl {tris (oxyethylene)} oxycarbonyl-p-phenyleneimino] fullerene (abbreviated name BABC60) were blended.referenceSame as example 1PhotosensitivityA composition was obtained.
  In this example, BABC60 not only serves as a fine particle but also serves as a crosslinking agent.
[0047]
  Here, the fullerene C60 derivative BABC60 was synthesized by the method described below. First, a mixture of 10 g of triethylene glycol and 5 g of triethylamine was cooled to 0 ° C., and a solution of 1 g of p-azidobenzoic acid chloride dissolved in 20 ml of tetrahydrofuran was added dropwise thereto, and the mixture was stirred at 0 ° C. for 12 hours at room temperature. The reaction was performed for 6 hours. The reaction product was then dissolved in 300 ml of 3N aqueous hydrochloric acid and extracted with chloroform. Thereafter, the extract was washed with saturated brine, the chloroform layer was separated, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain triethylene glycol mono (p-azidobenzoic acid) ester (hereinafter abbreviated as TGBA). 3 g was obtained.
  Subsequently, 2 g of TGBA 1.3 and fullerene C60 were heated at 160 ° C. for 6 hours while stirring in 100 ml of ortho-dichlorobenzene, and concentrated under reduced pressure to 30 ml. Subsequently, it was eluted and separated with ortho-dichlorobenzene by column chromatography using styrene gel as a stationary phase, and the third stream was concentrated under reduced pressure to make the total volume 30 ml. The first stream was a small amount of unreacted fullerene C60, and the second stream was a mono-substituted product of the target product.
  Thereafter, 5 g of triethylamine and 3 g of p-azidobenzoic acid chloride are added to the concentrate of the third stream and reacted at room temperature for 24 hours, and then the reaction product is concentrated under reduced pressure to use styrene gel as a stationary phase. Elution and separation with ortho-dichlorobenzene was performed by chromatography, and the main stream was dried under reduced pressure to obtain 0.65 g of BABC60.
[0048]
  like thisPhotosensitivityUsing the composition, a fine pattern was formed on a silicon substrate as follows.
  First, as shown in FIG. 2A, a resist solution was spin-coated on the silicon substrate 1 and heat-treated to form a 50 nm thick resist film 2 on the silicon substrate 1. Then, the high energy beam 3 was irradiated to the resist film 2 using the electron beam exposure apparatus with an acceleration voltage of 100 kV.
  Next, as shown in FIG. 2B, a development process is performed on the resist film 2 irradiated with the high energy rays 3 using a commercially available developer for ZEP resist as a developer with a development time of 30 seconds. The irradiated region was removed, and a fine pattern 4a having a dimension of about 15 nm was formed on the resist film 2.
  Next, as shown in FIG. 2C, the entire surface of the resist film 2 on which the fine pattern 4a is formed is irradiated with ultraviolet rays having a wavelength of 365 nm, which is the second high-energy ray 5, so that the fine particles 10 and the crosslinking agent 20b are irradiated. As shown in FIG. 2D, a cross-linking bond 30 is formed and the resist film 2 is cured.
  Next, as shown in FIG.₂F₆The silicon substrate 1 is dry-etched using the resist film 2 cured by using the mask as a mask, and the fine pattern 4b is applied to the silicon substrate 1 based on the fine pattern 4a of the resist film 2 as shown in FIG. Formed.
[0049]
Example 14)
  Example 1 except that 10 parts by mass of a fullerene C60 / C70 mixture (mixing ratio: about 4/1) was blended as fine particles instead of 10 parts by mass of fullerene C60.3LikePhotosensitivityA composition was obtained and further3In the same manner, a fine pattern was formed on the silicon substrate.
[0050]
Example 15)
  Example 1 except that 10 parts by weight of fullerene derivative C60φOφ was blended in place of 10 parts by weight of fullerene C60 as fine particles.3LikePhotosensitivityA composition was obtained and further3In the same manner, a fine pattern was formed on the silicon substrate.
[0051]
Example 16)
  As a resist, positiveTypeExample 1 except that 100 parts by mass of the solid content of a chemically amplified resist for a KrF excimer laser was used instead of 100 parts by mass of the solid content of the electron beam resist ZEP520.3LikePhotosensitivityA composition was obtained and further3In the same manner, a fine pattern was formed on the silicon substrate.
[0052]
Example 17)
  As a resist, positiveTypeInstead of 100 parts by mass of the solid content of the electron beam resist ZEP520, 100 parts by mass of a commercially available chemical amplification system resist for KrF excimer laser was used, and instead of fullerene C60, a fullerene C60 / C70 mixture (mixing ratio of about 4 / Example 1 except that 1) was blended3LikePhotosensitivityA composition was obtained and further3In the same manner, a fine pattern was formed on the silicon substrate.
[0053]
Example 18)
  As a resist, positiveTypeInstead of 100 parts by mass of the solid content of the electron beam resist ZEP520, 100 parts by mass of a commercially available KrF excimer laser chemically amplified resist is used, and instead of the fullerene C60,referenceExample 1 except that the fullerene derivative C60φOφ used in Example 3 was blended and the fullerene C60 derivative C60φOφ and the fullerene C60 derivative BABC60 were dissolved in the PGMEA solvent.3LikePhotosensitivityA composition was obtained and further3In the same manner, a fine pattern was formed on the silicon substrate.
[0054]
  Example 118In, it has a resist, fine particles and a crosslinking agentPhotosensitivityBy using the composition, a strong resist film having an initial film thickness of 50 nm could be formed, and thus a pattern having a depth of 70 nm and a width of 15 nm could be formed on the silicon substrate with high accuracy. In addition, no defects occurred in the silicon substrate.
[0055]
【The invention's effect】
  As explained above, the present inventionPhotosensitivityAccording to the composition, a fine resist film having a three-dimensional stitch structure can be obtained by crosslinking fine particles composed of one or both of a highly resistant fullerene and a fullerene derivative with a crosslinking agent. The resist film having such a three-dimensional stitch structure is excellent in dry etching resistance, heat resistance, and mechanical strength. Even if the film thickness is further reduced, the formation of defects on the substrate can be prevented. As a result, a highly accurate nanometer Level fine pattern formation can be realized.
[Brief description of the drawings]
FIG. 1 of the present inventionPhotosensitivityIt is a figure explaining an example of the fine pattern formation process using a composition.
FIG. 2 of the present inventionPhotosensitivityIt is a figure explaining the other example of the fine pattern formation process using a composition.
Fig. 3 ConventionalPhotosensitivityIt is a figure explaining the fine pattern formation process using a composition.
[Explanation of symbols]
10: Fine particles (fine particles) composed of one or both of fullerenes and fullerene derivatives, 20a, 20b ... crosslinking agents

Claims (8)

A resist, and fine particles of one or both of the fullerene and fullerene derivative, the crosslinking agent possess,
The photosensitive composition according to claim 1, wherein the crosslinking agent is borazine or a borazole derivative . The crosslinking agent further amino compounds, azide compounds, diazo compounds, photosensitive composition according to claim 1, characterized in that it comprises at least one selected from hydroxyl group-containing compound. The resist photosensitive composition according to claim 1 or claim 2, wherein the acrylic resin resist. The resist according to claim 1 or claim 2 photosensitive composition as described is characterized by having a alkali-soluble resin and a photosensitive agent. A resist, fine particles composed of one or both of fullerene and a fullerene derivative, and a crosslinking agent,
The photosensitive composition is a chemically amplified resist having an alkali-soluble resin, an acid generator, and a solubility control agent having an acid labile group . The photosensitive composition according to claim 5 , wherein the crosslinking agent is borazine or a borazole derivative . 6. The photosensitive composition according to claim 5 , wherein the crosslinking agent further contains at least one selected from an amino compound, an azide compound, a diazo compound, and a hydroxyl group-containing compound . A photosensitive composition according to any one of claims 1 to 7 is irradiated with a high-energy ray, and a space between at least two of a resist, fine particles comprising one or both of fullerene and a fullerene derivative, and a crosslinking agent. A method for curing a photosensitive composition, wherein a chemical bond is formed on the photosensitive composition.

Images