Pattern formation method

Abstract

This pattern formation method comprises: a film formation step for attaching a diacetylene derivative-containing substance to a substrate to form a film of the diacetylene derivative-containing substance on the substrate; a polymerization step for causing a polymerization reaction of the diacetylene derivative in at least a portion of the film of the diacetylene derivative-containing substance to generate a polymer of the diacetylene derivative on the substrate; and a removal step for removing the film of the diacetylene derivative-containing substance formed on the substrate to form a pattern of the polymer of the diacetylene derivative on the substrate.

Description

Pattern Formation Method

[0001] The present disclosure relates to a patterning method.

[0002] The following non-patent document 1 discloses that, during the synthesis of a diacetylene derivative sandwiched between two cholesterol moieties and two urethane bonds, the resulting compound gels a non-polar solvent such as cyclohexane, and the gel then changes color from colorless to blue upon exposure to ultraviolet light.

[0003] Non-Patent Document 2 below discloses that an LB film was evaluated by excimer laser exposure, that the materials evaluated were three types of diacetylene derivatives for excimer use (tricosadiynoic acid: TDA, pentacosadiynoic acid: PDA, and heptacosadiynoic acid: HDA), and that a 0.3 μm pattern was formed using PDA in the excimer exposure.

[0004] Nobuyuki Tamaki, "Polymerization of Diacetylene Self-Assemblies," Polymers, Vol. 55, August, pp. 611-615 (2006); Kazufumi Ogawa and Hideharu Tamura, "Evaluation of LB Films as Resists for Excimer Laser Exposure and X-ray Exposure," Journal of the Institute of Television Engineers, Vol. 42, No. 1, pp. 56-62 (1998)

[0005] The present disclosure provides a technique that allows for pattern formation with a higher degree of freedom.

[0006] A pattern forming method according to one aspect of the present disclosure includes a film forming step of forming a film of a material containing a diacetylene derivative on a substrate by attaching the material to the substrate; a polymerization step of producing a polymer of the diacetylene derivative on the substrate by inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film of the material containing the diacetylene derivative; and a removal step of forming a pattern of the polymer of the diacetylene derivative on the substrate by removing the film of the material containing the diacetylene derivative formed on the substrate.

[0007] According to the present disclosure, patterns can be formed with a higher degree of freedom.

[0008] Fig. 1 is a flowchart illustrating an example of a pattern forming method according to an embodiment. Fig. 2A is a schematic diagram illustrating an example of a pattern forming method according to an embodiment. Fig. 2B is a schematic diagram illustrating an example of a pattern forming method according to an embodiment. Fig. 3 is a diagram illustrating a line pattern formed by irradiating an electron beam on a thin film of DPLe according to Example 1.

[0009] Hereinafter, a detailed description will be given of a pattern formation method according to the present disclosure (hereinafter referred to as an "embodiment") with reference to the drawings. Note that the present disclosure is not limited to the embodiment. Furthermore, the embodiments can be appropriately combined within the scope of not causing any contradiction in the processing content. Furthermore, the same components in the following embodiments are denoted by the same reference numerals, and redundant explanations will be omitted.

[0010] For example, when manufacturing a semiconductor device having a fine structure by a lithography process, a mask having a predetermined pattern is used to etch a substrate, etc. The mask having the predetermined pattern is formed by irradiating a resist provided on a substrate with ultraviolet (UV), extreme ultraviolet (EUV), or electron beam (EB) according to the design of the semiconductor device.

[0011] Therefore, it is preferable to use a resist that can form a mask having a predetermined pattern not only with ultraviolet light but also with extreme ultraviolet light or electron beams. It is also preferable to use a resist that can form a mask having a predetermined pattern according to various irradiation intensities and durations of ultraviolet light, extreme ultraviolet light, or electron beams. Thus, there is a demand for a resist that can form a mask having a predetermined pattern with a high degree of freedom under various conditions.

[0012] Therefore, the present disclosure provides a technique that allows patterns to be formed with a higher degree of freedom.

[0013] (Pattern Forming Method) Fig. 1 is a flowchart showing an example of a pattern forming method according to an embodiment. Figs. 2A and 2B are schematic views illustrating an example of a pattern forming method according to an embodiment. Fig. 2A shows a state of a substrate and the like viewed from a direction along the surface of the substrate in the example of the pattern forming method. Fig. 2B shows a state of a substrate and the like viewed from a normal direction to the surface of the substrate in the example of the pattern forming method.

[0014] As shown in FIG. 1, the pattern forming method according to the embodiment includes a preparation step (step S101), a film formation step (step S102), a polymerization step (step S103), and a removal step (step S104).

[0015] First, in the preparation step of step S101 shown in Fig. 1, a substrate 10 is prepared as shown in Fig. 2A(a) and Fig. 2B(a). The substrate 10 is made of a material that is insoluble in organic solvents and the like used in the removal step (step S104) described below. The substrate 10 may also be made of a material that can be etched. Examples of the substrate 10 include a quartz glass substrate and a silicon substrate.

[0016] 1, a substance containing a diacetylene derivative is attached to the substrate 10 as shown in (b) of FIG. 2A and (b) of FIG. 2B. This forms a film 20 of the substance containing a diacetylene derivative on the substrate 10. The diacetylene derivative is a compound represented by the general formula X1-C≡C-C≡C-X2, where X1 and X2 are substituents.

[0017] An example of a method for attaching a substance containing a diacetylene derivative to the substrate 10 is a method of applying the substance containing a diacetylene derivative to the substrate 10. The method of applying the substance containing a diacetylene derivative to the substrate 10 includes dissolving the diacetylene derivative in a solvent to obtain a solution of the diacetylene derivative, applying the solution of the diacetylene derivative to the surface of the substrate 10 to form a film of the solution of the diacetylene derivative on the surface of the substrate 10, and baking the film of the solution of the diacetylene derivative formed on the surface of the substrate 10.

[0018] Examples of the solvent include organic solvents such as ethyl acetate. Examples of a method for applying the solution containing the diacetylene derivative to the substrate 10 include spin coating using a spin coater. Note that, before applying the solution of the diacetylene derivative to the substrate 10, the surface of the substrate 10, such as a silicon substrate, may be treated with a surface treatment agent such as hexamethyldisilazane (HDMS).

[0019] When the substance containing a diacetylene derivative is applied to the substrate 10, it becomes possible to form a film 20 of the substance containing a diacetylene derivative more uniformly (smootherly).In addition, it becomes possible to adjust the thickness of the film 20 of the substance containing a diacetylene derivative more easily.

[0020] An example of a method for attaching a substance containing a diacetylene derivative to the substrate 10 is a method of vacuum-depositing the diacetylene derivative on the substrate 10. The method of vacuum-depositing the diacetylene derivative on the substrate 10 includes heating the diacetylene derivative in a vacuum to evaporate the diacetylene derivative, and depositing the diacetylene derivative on the surface of the substrate 10 to form a thin film of the diacetylene derivative on the surface of the substrate 10.

[0021] A vacuum deposition method using a vacuum deposition apparatus can be used as a method for vacuum-depositing a diacetylene derivative on the substrate 10. When vacuum-depositing a diacetylene derivative on the substrate 10, it becomes possible to form a thin film of the diacetylene derivative, which is poorly soluble in organic solvents, on the surface of the substrate 10. It also becomes possible to form a thin film of the diacetylene derivative on various surfaces of the substrate 10.

[0022] 1, a polymerization reaction of the diacetylene derivative is caused in at least a portion of the film 20 of the diacetylene derivative-containing substance, as shown in (c) of FIG. 2A and (c) of FIG. 2B. The polymerization reaction of the diacetylene derivative in at least a portion of the film 20 of the diacetylene derivative-containing substance means that a polymerization reaction of the diacetylene derivative is caused in the entire or a portion of the film 20 of the diacetylene derivative-containing substance. This produces a polymer 30 of the diacetylene derivative on the substrate 10.

[0023] An example of a method for inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film 20 of the diacetylene derivative-containing substance is heating at least a portion of the film 20 of the diacetylene derivative-containing substance. Another example of a method for inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film 20 of the diacetylene derivative-containing substance is irradiating at least a portion of the film 20 of the diacetylene derivative-containing substance with electromagnetic waves. Examples of electromagnetic waves include ultraviolet (UV) rays and extreme ultraviolet (EUV) rays. Ultraviolet rays are, for example, electromagnetic waves having a wavelength of 20 nm or more and 400 nm or less. Extreme ultraviolet rays are, for example, electromagnetic waves having a wavelength of 5 nm or more and 20 nm or less. Another example of a method for inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film 20 of the diacetylene derivative-containing substance is irradiating at least a portion of the film 20 of the diacetylene derivative-containing substance with an electron beam (EB).

[0024] When at least a portion of the film 20 of the substance containing the diacetylene derivative is irradiated with electromagnetic waves or electron beams, it becomes possible to more easily induce a polymerization reaction of the diacetylene derivative in at least a portion of the film 20 of the substance containing the diacetylene derivative. Therefore, the film 20 of the substance containing the diacetylene derivative is irradiated with electromagnetic waves or electron beams according to a predetermined pattern.

[0025] An example of a method for irradiating ultraviolet light onto at least a portion of the film 20 of the diacetylene derivative-containing substance is a method using a UV irradiation device to irradiate ultraviolet light onto at least a portion of the film 20 of the diacetylene derivative-containing substance. For example, by irradiating the film 20 of the diacetylene derivative-containing substance with ultraviolet light that has passed through a mask with a predetermined pattern and a projection lens, a polymerization reaction of the diacetylene derivative is caused in selective regions of the film 20 of the diacetylene derivative-containing substance.

[0026] An example of a method for irradiating ultraviolet light onto at least a portion of the film 20 of a substance containing a diacetylene derivative is a method in which an EUV exposure apparatus is used to irradiate extreme ultraviolet light onto at least a portion of the film 20 of a substance containing a diacetylene derivative. For example, extreme ultraviolet light that has passed through a mask with a predetermined pattern and a projection lens is irradiated onto the film 20 of a substance containing a diacetylene derivative, thereby inducing a polymerization reaction of the diacetylene derivative in selective regions of the film 20 of a substance containing a diacetylene derivative.

[0027] An example of a method for irradiating ultraviolet light onto at least a portion of the film 20 of the diacetylene derivative-containing substance is a method using an electron beam lithography device to irradiate an electron beam onto at least a portion of the film 20 of the diacetylene derivative-containing substance. For example, by scanning the film 20 of the diacetylene derivative-containing substance with an electron beam, a polymerization reaction of the diacetylene derivative is induced in selective regions of the film 20 of the diacetylene derivative-containing substance.

[0028] In the film 20 of the material containing the diacetylene derivative, a plurality of molecules of the diacetylene derivative represented by the general formula X1-C≡C-C≡C-X2 are As shown in Figure 1, the substituents X1 and X2 approach each other due to the intermolecular force between them, and are thereby spontaneously arranged in a regular pattern (directed self-assembly (DSA) of diacetylene derivatives).

[0029] Here, when a polymerization reaction of the diacetylene derivative is caused, a 1,4-topochemical polymerization reaction of the diacetylene derivative occurs in a state where a plurality of molecules of the diacetylene derivative are regularly arranged. Thus, a polymer 30 of the diacetylene derivative is produced, which is a polydiacetylene derivative represented by the formula: In this way, since a plurality of molecules of the acetylene derivative are regularly arranged in the film 20 of the substance containing the diacetylene derivative, polymerization of a plurality of molecules of the diacetylene derivative is promoted. As a result, it becomes possible to produce the polymer 30 of the diacetylene derivative more easily.

[0030] 1, the film 20 of the substance containing a diacetylene derivative formed on the substrate 10 is removed as shown in (d) of FIG. 2A and (d) of FIG. 2B. That is, the film 20 of the substance containing a diacetylene derivative excluding the polymer 30 of the diacetylene derivative is removed from the substrate 10. This forms a pattern of the polymer 30 of the diacetylene derivative on the substrate 10. In other words, the pattern of the polymer 30 of the diacetylene derivative is developed on the substrate 10. When the film 20 of the substance containing a diacetylene derivative is used as a resist in a lithography process, the film 20 of the substance containing a diacetylene derivative functions as a negative resist.

[0031] A method for removing the film 20 of the substance containing the diacetylene derivative formed on the substrate 10 includes, for example, dip development using an organic solvent that dissolves the diacetylene derivative but does not dissolve the polymer 30 of the diacetylene derivative. Examples of such organic solvents include ethyl acetate and hexane. By dissolving and removing the film 20 of the substance containing the diacetylene derivative formed on the surface of the substrate 10 with such an organic solvent, a pattern of the polymer 30 of the diacetylene derivative that is insoluble in the organic solvent is formed on the surface of the substrate 10.

[0032] As described above, in the film 20 of the substance containing the diacetylene derivative, a plurality of molecules of the diacetylene derivative are polymerized in a state where the plurality of molecules of the diacetylene derivative are regularly arranged, thereby producing the diacetylene derivative polymer 30. This is thought to reduce the unevenness of the surface of the pattern of the diacetylene derivative polymer 30. In other words, it is thought to reduce the roughness of the pattern of the diacetylene derivative polymer 30. In this way, it becomes possible to form a pattern of the diacetylene derivative polymer 30 with reduced roughness on the substrate 10.

[0033] For example, when the pattern of the diacetylene derivative polymer 30 is a line pattern, it is possible to reduce line edge roughness (LER) or line width roughness (LWR) as roughness of the sidewalls of the line pattern, and it is possible to form a line pattern with reduced line edge roughness (LER) or line width roughness (LWR).

[0034] The change in the distance between the multiple units (-CX1-C≡C-C≡C-CX2-) constituting the diacetylene derivative polymer 30 relative to the distance between the multiple molecules of the acetylene derivative in the film 20 of the diacetylene derivative-containing substance is relatively small. Therefore, the change in the size of the diacetylene derivative polymer 30 relative to the size of the region where the polymerization reaction of the diacetylene derivative has occurred in the film 20 of the diacetylene derivative-containing substance is relatively small. As a result, it becomes possible to more easily adjust the size of the diacetylene derivative polymer 30.

[0035] For example, when irradiating the film 20 of the substance containing the diacetylene derivative with electromagnetic waves or electron beams, it becomes possible to more easily adjust the region of the film 20 of the substance containing the diacetylene derivative that is irradiated with the electromagnetic waves or electron beams, thereby making it possible to more easily adjust the size of the polymer 30 of the diacetylene derivative.

[0036] Thereafter, a step of etching the substrate 10 may be carried out using the pattern of the diacetylene derivative polymer 30 as a mask. When the substrate 10 is a silicon substrate, examples of the etching method include wet etching using an aqueous potassium hydroxide (KOH) solution and dry etching using plasma of a gas containing fluorine or chlorine.

[0037] Here, the pattern of the diacetylene derivative polymer 30 with reduced roughness can be transferred to the substrate 10. Therefore, it is considered that the roughness of the etched substrate 10 is comparable to the roughness of the pattern of the diacetylene derivative polymer 30. In this way, it is possible to reduce the roughness of the etched substrate 10.

[0038] As described above, a polymer 30 of the diacetylene derivative is produced on the substrate 10 by inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film 20 of a substance containing the diacetylene derivative. By appropriately selecting the substituents in the diacetylene derivative according to the conditions for forming a pattern of the diacetylene derivative polymer 30, it becomes possible to appropriately induce the polymerization reaction of the diacetylene derivative. In other words, by appropriately selecting the substituents in the diacetylene derivative, it becomes possible to form a pattern of the diacetylene derivative polymer 30 with a higher degree of freedom.

[0039] For example, it is possible to form a pattern of the diacetylene derivative polymer 30 not only by ultraviolet light but also by extreme ultraviolet light or an electron beam. For example, it is possible to form a pattern of the diacetylene derivative polymer 30 according to various irradiation intensities and durations of ultraviolet light, extreme ultraviolet light, or an electron beam.

[0040] The polymerization step preferably includes irradiating extreme ultraviolet light onto at least a portion of the film 20 of the diacetylene derivative-containing material to induce a polymerization reaction of the diacetylene derivative. In this case, since the wavelength of the extreme ultraviolet light is short, it is possible to improve the resolution of the extreme ultraviolet light. It is also possible to reduce the pattern size of the diacetylene derivative polymer 30.

[0041] The polymerization step involves irradiating at least a portion of the film 20 of the diacetylene derivative-containing material with an electron beam to induce a polymerization reaction of the diacetylene derivative. In this case, the electron beam can be moved at high speed, which makes it possible to induce the polymerization reaction of the diacetylene derivative more efficiently. Furthermore, the fluctuation in the output of the electron beam can be reduced, which makes it possible to induce the polymerization reaction of the diacetylene derivative more uniformly. Therefore, it becomes possible to form a pattern of the diacetylene derivative polymer 30 more efficiently and uniformly.

[0042] (Diacetylene Derivative) Next, the diacetylene derivative used in the pattern formation method according to the embodiment will be described in more detail. As described above, the diacetylene derivative is a compound represented by the general formula X1-C≡C-C≡C-X2, where X1 and X2 are substituents.

[0043] Here, a diacetylene derivative represented by the general formula X1-C≡C-C≡C-X2 can be synthesized, for example, by an oxidative coupling reaction of acetylene derivatives represented by the general formulas H-C≡C-X1 and H-C≡C-X2 in the presence of oxygen and a suitable catalyst.

[0044] For example, diacetylene derivatives include: The compound may be represented by the formula:

[0045] The diacetylene derivative is preferably a symmetric diacetylene derivative. A symmetric diacetylene derivative is a diacetylene derivative in which the substituents at both ends are the same. That is, a symmetric diacetylene derivative is a diacetylene derivative represented by the general formula X1-C≡C-C≡C-X2 in which the substituents X1 and X2 are the same.

[0046] In this case, since the substituents at both ends of the diacetylene derivative are the same, the intermolecular forces acting between the terminal substituents of the multiple diacetylene derivative molecules become more uniform. Accordingly, the multiple acetylene derivative molecules are more easily arranged in a regular pattern in the film 20 of the material containing the diacetylene derivative. This further promotes polymerization of the multiple diacetylene derivative molecules. As a result, it becomes possible to more easily produce the diacetylene derivative polymer 30.

[0047] For example, diacetylene derivatives include: The compound may be represented by the formula:

[0048] The substituent in the diacetylene derivative preferably includes a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted acyloxy group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group. Here, the alkoxy group, the aryloxy group, the acyloxy group, the alkoxycarbonyl group, and the aryloxycarbonyl group are groups represented by HOCO-, RO-, ArO-, R / Ar-COO-, ROCO-, and ArOCO-, respectively. Furthermore, R and Ar represent an alkyl group and an aryl group, respectively. R / Ar means an alkyl group or an aryl group. Substituted or unsubstituted means that the alkyl group or the aryl group is substituted or not substituted with a substituent.

[0049] In this case, it is possible to appropriately adjust the intermolecular force acting between the terminal substituents of multiple diacetylene derivative molecules. As a result, it is possible to appropriately control the distance between multiple acetylene derivative molecules in the film 20 of a substance containing the diacetylene derivative. Therefore, it is possible to appropriately control the polymerization of multiple diacetylene derivative molecules. As a result, it is possible to appropriately generate the diacetylene derivative polymer 30 depending on the conditions for forming the diacetylene derivative polymer 30.

[0050] The number of carbon atoms contained in the substituent in the diacetylene derivative is from 1 to 30. In this case, it becomes possible to appropriately control the production of the polymer 30 of the diacetylene derivative.

[0051] Since the number of carbon atoms contained in the substituent in the diacetylene derivative is one or more, it is possible to increase the intermolecular force acting between the terminal substituents in multiple molecules of the diacetylene derivative. As a result, it is possible to reduce the distance between multiple molecules of the acetylene derivative in the film 20 of the substance containing the diacetylene derivative. Therefore, it is possible to promote polymerization of multiple molecules of the diacetylene derivative. As a result, it is possible to promote the production of a polymer 30 of the diacetylene derivative.

[0052] On the other hand, since the number of carbon atoms contained in the substituent in the diacetylene derivative is 30 or less, it is possible to suppress an excessive increase in the intermolecular force acting between the terminal substituents in multiple diacetylene derivative molecules. As a result, it is possible to suppress an excessive decrease in the distance between multiple acetylene derivative molecules in the film 20 of the substance containing the diacetylene derivative. As a result, it is possible to suppress the excessive production of diacetylene derivative polymer 30.

[0053] The substituent in the diacetylene derivative preferably includes an arylene group. In this case, it is possible to increase the melting point of the diacetylene derivative. As a result, for example, when the diacetylene derivative is vacuum-deposited on the substrate 10, it is possible to suppress excessive evaporation of the diacetylene derivative. As a result, when the diacetylene derivative is vacuum-deposited on the substrate 10, it is possible to more easily produce the polymer 30 of the diacetylene derivative.

[0054] For example, diacetylene derivatives include: The compound may be represented by the formula:

[0055] The substituent in the diacetylene derivative preferably includes an amide bond (—NH—CO—). In this case, it is possible to utilize the hydrogen bond between the hydrogen and oxygen of the amide bond in the plurality of diacetylene derivative molecules as the intermolecular force acting between the terminal substituents in the plurality of diacetylene derivative molecules. Accordingly, it is possible to increase the intermolecular force acting between the terminal substituents in the plurality of diacetylene derivative molecules. As a result, it is possible to reduce the distance between the plurality of acetylene derivative molecules in the film 20 of the material containing the diacetylene derivative. Therefore, it is possible to promote polymerization of the plurality of diacetylene derivative molecules. As a result, it is possible to promote the production of the diacetylene derivative polymer 30.

[0056] For example, diacetylene derivatives include: The compound may be represented by the formula:

[0057] The substituent in the diacetylene derivative preferably includes a fluoro group (-F). In this case, when the substrate 10 is a silicon substrate, it becomes possible to more easily attach a substance including a diacetylene derivative to the substrate 10. As a result, it becomes possible to more easily produce a polymer 30 of the diacetylene derivative on the substrate 10.

[0058] For example, the diacetylene derivative is F １３ C ６ - (CH ２ ) ２ -O-CH ２ -C≡C-C≡C-CH ２ -O-(CH ２ ) ２ -C ６ F １３ The compound may be represented by the formula:

[0059] The substituents in the diacetylene derivatives are preferably siloxane bonds ((—SiR1R2—O—) ｎ) where R1 and R2 are alkyl groups. R1 and R2 may be the same as or different from each other. The number of carbon atoms contained in R1 and R2 is, for example, 1 to 6. n is a natural number of 1 to 10. In this case, when the substrate 10 is a silicon substrate, it becomes possible to more easily attach a substance containing a diacetylene derivative to the substrate 10. As a result, it becomes possible to more easily produce a polymer 30 of the diacetylene derivative on the substrate 10.

[0060] For example, the diacetylene derivative is R3-C≡C-C≡C-CH ２ —O—Si(CH ３ ) ２ —O—Si(CH ３ ) ２ —O—Si(CH ３ ) ２ —O—Si(CH ３ ) ２ -O-CH ２ The compound may be a compound represented by —C≡C—C≡C—R3, where R3 is an alkyl group. The number of carbon atoms contained in R3 is, for example, 1 or more and 18 or less.

[0061] The substituent in the diacetylene derivative is preferably an ethylene glycol unit ((-CH ２ -CH ２ -O-) ｎ ) where n is a natural number of 1 to 10. For example, the substituent in the diacetylene derivative includes a diethylene glycol unit ((-CH ２ -CH ２ -O-) ２ ) or triethylene glycol unit ((-CH ２ -CH ２ -O-) ３ In this case, when the substrate 10 is a silicon substrate, the use of an ethylene glycol-based solvent makes it possible to more easily apply a substance containing a diacetylene derivative to the substrate 10. As a result, it becomes possible to more easily produce a polymer 30 of the diacetylene derivative on the substrate 10.

[0062] Examples of the present disclosure will be specifically described below, but the present disclosure is not limited to the examples shown below.

[0063] Example 1: A mixture of lauroyl chloride (9.40 mL, 39.4 mmol) and dry THF (25 mL) was added dropwise to a mixture of propargyl alcohol (2.00 mL, 35.8 mmol), triethylamine (6.00 mL, 44.0 mmol), and dry THF (25 mL) in a 100 mL recovery flask in an ice bath, and the mixture was stirred at room temperature for 20 hours. The mixture was then extracted with saturated sodium bicarbonate (40 mL) and ethyl acetate (30 mL x 3), and washed with saturated brine (50 mL x 3). The organic layer was dehydrated over anhydrous magnesium sulfate, and the filtrate was concentrated using an evaporator. The residue was purified by silica gel chromatography (dichloromethane). Lauroyl-propargyl ester (PLe) (4.07 g, 24.1 mmol) was obtained (form: viscous liquid / color: colorless / molecular weight (MW): 238.37 / １ H NMR (solvent: CDCl ３ ) 0.88-1.63 (21H, m, alkyl chain protons), 2.30-2.39 (2H, m, -CH ２ -CO), 2.51 (1H, t, J = 5.2Hz, ≡CH), 4.73 (2H, s, ≡C-CH ２ -).

[0064] Next, PLe (1.69 g, 7.07 mmol), copper(II) acetate monohydrate (2.02 g, 10.1 mmol), and acetonitrile (30 mL) were placed in a 100 mL recovery flask and stirred at 60°C under a nitrogen atmosphere for 22 hours. After concentration, 1.0 M hydrochloric acid was added, extracted with chloroform (50 mL x 3), and washed with saturated brine (50 mL x 3). The filtrate was concentrated using an evaporator. The residue was purified by silica gel chromatography (dichloromethane) to obtain dipropargyl lauroyl ester (DPLe) (1.56 g, 3.29 mmol) (form: solid; color: colorless; molecular weight (MW): 474.73; melting point (mp): 57-60°C; １ H NMR (solvent: CDCl ３ ) 0.88-1.63 (42H, m, alkyl chain protons), 2.30-2.39 (4H, m, -CH２ -CO), 4.73 (4H, s, ≡C-CH ２ -).

[0065]

[0066] A thin film of DPLe was prepared using a small vacuum deposition apparatus (ULVAC: VPC-060A). Specifically, 20 mg of DPLe was placed on a tungsten boat of the small vacuum deposition apparatus. A silicon substrate (a silicon substrate cleaned with Semicoclean 23 and a silicon substrate treated with HMDS) and an organic thin film-treated Si substrate were fixed to the deposition plate of the small vacuum deposition apparatus. Pressure at the start of deposition: 2.98 × 10 －３ A thin film of DPLe was formed on each substrate by vapor deposition of DPLe under the conditions of 1 Pa, a current of 20 A, and a shutter open time of 0 to 60 seconds.

[0067] Next, an electron beam lithography system (ELS-7500EX manufactured by Elionix) was used to irradiate the ion beam at 100 to 6000 μC / cm ２ The thin film of DPLe was irradiated with an electron beam at an exposure dose of 1000 u / s. The substrate with the thin film after electron beam irradiation was then immersed in ethyl acetate for 60 seconds as development. The substrate with the developed thin film was dried, and the surface of the thin film was observed using an optical microscope (Olympus: BX51M). It was confirmed that for both silicon substrates, a good pattern could be formed on the thin film of DPLe by irradiating the thin film with EB.

[0068] Next, using an electron beam lithography system, 40, 80, 120, 160, 200, and 240 μC / cm ２ A line pattern was formed by irradiating the DPLe thin film with an electron beam at an exposure dose of 1000 . The line patterns were two lines measuring 2.4 mm in length and 10 μm in width, two lines measuring 2.4 mm in length and 5 μm in width, and five lines measuring 2.4 mm in length and 1 μm in width. For development, the substrate with the thin film after electron beam irradiation was immersed in ethyl acetate for 30 seconds. After drying the substrate with the developed thin film, the surface of the thin film was observed using an optical microscope.

[0069] 3A, 3B, 3C, 3D, 3E, and 3F are diagrams showing line patterns formed by irradiating a thin film of DPLe with an electron beam according to Example 1. In FIG. 3A, 3B, 3C, 3D, 3E, and 3F, the line patterns are formed at irradiating rates of 40, 80, 120, 160, 200, and 240 μC / cm, respectively. ２ 3 shows a line pattern formed with an exposure dose of at least 40 μC / cm In (a), (b), (c), (d), (e), and (f) of FIG. 3, the two lines on the left side are two lines with a length of 2.4 mm and a width of 10 μm. The two lines in the middle are two lines with a length of 2.4 mm and a width of 5 μm. The five lines on the right side are two lines with a length of 2.4 mm and a width of 5 μm. Thus, for the thin film of DPLe according to Example 1, a dose of at least 40 μC / cm ２ or more and 240 μC / cm ２ It was confirmed that a line pattern could be formed with an exposure dose of 1000 nm.

[0070] (Example 2) 4-Hydroxybenzoic acid (1.01 g, 7.24 mmol), 1-decanol (2.00 mL, 10.8 mmol), p-toluenesulfonic acid monohydrate (a small amount), and toluene (30.0 mL) were added to a 100 mL recovery flask, and the mixture was heated and stirred at an oil bath temperature of 130°C. After cooling, the solid remaining in the solution was separated by suction filtration, and the filtrate was concentrated. The residue was dissolved in ethyl acetate (60 mL), washed with a saturated aqueous solution of NaCl (20 mL x 3), and concentrated. ２ SO ４ After drying, the mixture was filtered and the solvent was distilled off under reduced pressure to obtain a crude product. Silica gel chromatography (n-hexane / ethyl acetate = 5 / 1, v / v) (Rf = 0.19) was performed to obtain De4-HyB (1.56 g, 5.59 mmol) (form: solid / color: colorless / molecular weight (MW): 278.39 / melting point (mp): 45-49°C / １ H NMR (solvent: CDCl ３ ) 0.87 (3H, t, J=6.87Hz, -CH ３ ), 1.17-1.47 (16H, m, alkyl chain protons), 1.70-1.79 (2H, m, -CH ２ -), 4.27 (2H, t, J=6.87Hz, -CH ２—O—CO—), 6.10 (1H, s, —OH), 6.94-7.01 (2H, m, aromatic protons), 7.90-8.07 (2H, m, aromatic protons).

[0071] Next, propargyl bromide (0.41 g, 4.44 mmol), potassium carbonate (0.41 g, 2.87 mol), De4-HyB (0.80 g, 2.87 mmol), and acetone (30 mL) were added to a 100 mL recovery flask and heated with stirring at 50°C for 5 hours. After cooling, the reaction solution was concentrated under reduced pressure and extracted with ethyl acetate (20 mL x 3). The organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography (n-hexane / ethyl acetate = 1 / 1, v / v) (Rf = 0.24) to obtain P(De4-HyB)e (0.80 g, 2.53 mmol) (form: solid; color: colorless; molecular weight (MW): 316.43; melting point (mp): 45-47°C). １ H NMR (solvent: CDCl ３ ) 0.87 (3H, t, J=6.87Hz, -CH ３ ), 1.17-1.47 (16H, m, alkyl chain protons), 1.70-1.79 (2H, m, -CH ２ -), 2.53 (1H, t, J = 2.29Hz, ≡CH), 4.27 (2H, t, J = 6.87Hz, -CH ２ -O-CO-), 4.73 (2H, d, J = 2.29Hz, ≡C-CH ２ —O—), 6.94-7.01 (2H, m, aromatic protons), 7.90-8.07 (2H, m, aromatic protons).

[0072] Next, P(De4-HyB)e (0.50 g, 1.58 mmol), copper(II) acetate monohydrate (0.45 g, 2.26 mmol), and acetonitrile (30 mL) were placed in a 100 mL recovery flask and stirred at 60°C for 17 hours under a nitrogen atmosphere. 1.0 M hydrochloric acid was added, and the mixture was extracted twice with chloroform (50 mL x 3), followed by washing with saturated brine (50 mL x 3). The organic layer was dehydrated over anhydrous magnesium sulfate, and the filtrate was concentrated using an evaporator to obtain DP(De4-HyB)e (0.42 g, 6.66 mmol) (form: solid; color: colorless; molecular weight (MW): 630.85; melting point (mp): 88-90°C). １ H NMR (solvent: CDCl ３ )0.88 (6H, t, J=6.87Hz, -CH-CH ３ ), 1.17-1.47 (28H, m, alkyl chain), 1.69-1.74 (4H, m, CH ２ -CH ２ -CH ２ ), 4.27 (4H, t, J=6.87Hz, -CH ２ -O-CO-), 4.73 (4H, d, J=2.86, ≡C-CH ２ —O—), 6.96-7.00 (4H, m, Hz, aromatic protons), 7.96-8.03 (4H, m, aromatic protons).

[0073]

[0074] As in Example 1, a thin film of DP(De4-HyB)e was prepared using a small vacuum deposition apparatus. Specifically, 10 mg of DP(De4-HyB)e was placed on a tungsten boat. Two silicon substrates (purchased products) were fixed to the deposition plate. Pressure at the start of deposition: 4.66 x 10 －３ A thin film of DP(De4-HyB)e was formed on each substrate by vapor deposition of DP(De4-HyB)e under the conditions of 0 Pa, current: 23 A, and shutter open time: 0 to 60 seconds.

[0075] Next, an electron beam lithography system is used to irradiate the material with a radiation beam of 100 to 6000 μC / cm ２The DP(De4-HyB)e thin film was irradiated with an electron beam at an exposure dose of 1000 u / s. The substrate with the thin film after electron beam irradiation was then immersed in ethyl acetate for 10 or 60 seconds as development. The substrate with the developed thin film was dried, and the surface of the thin film was observed using an optical microscope. It was confirmed that for both silicon substrates, it was possible to form a relatively good pattern on the DP(De4-HyB)e thin film by irradiating it with EB.

[0076] (Example 3) 4-phenylphenol (1.86 g, 10.9 mmol), K ２ CO ３ (1.51 g, 10.9 mmol), 3-bromo-1-propyne (0.99 g, 8.41 mmol), and acetone (30 mL) were placed in a recovery flask and heated and stirred in a 45°C oil bath for 50 hours. The mixture was concentrated under reduced pressure and extracted with ethyl acetate (20 mL x 3) and water. The organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. Silica gel chromatography (n-hexane / dichloromethane = 15 / 1, v / v) (Rf = 0.17) was performed. PBPhe (1.54 g, 7.39 mmol) was obtained (form: solid; color: colorless; molecular weight (MW): 208.26; melting point (mp): 165-170°C or higher; １ H NMR (solvent: CDCl ３ ) 2.54 (1H, t, J = 2.86, -C≡CH), 4.73 (2H, d, J = 2.29, ≡C-CH ２ —O—), 7.02-7.57 (9H, m, aromatic protons).

[0077] Next, PBPhe (0.54 g, 2.59 mmol), copper(II) acetate monohydrate (0.74 g, 3.71 mmol), and acetonitrile (30 mL) were placed in a 100 mL recovery flask and stirred at 60°C for 20 hours under a nitrogen atmosphere. 1.0 M hydrochloric acid was added, and the mixture was extracted twice with chloroform (50 mL x 3), followed by washing with saturated brine (50 mL x 3). The organic layer was dehydrated over anhydrous magnesium sulfate, and the filtrate was concentrated using an evaporator. DPBPhe (0.920 g, 2.21 mmol) was obtained (form: solid; color: white; molecular weight (MW): 414.49; melting point (mp): 172-177°C; １ H NMR (solvent: CDCl ３ )4.69(4H,s,≡C-CH ２ —O—), 6.97-7.49 (18H, m, aromatic protons)).

[0078]

[0079] Similar to Example 1, a thin film of DPBPhe was prepared using a small vacuum deposition apparatus. Specifically, 10 mg of DPBPhe was placed on a tungsten boat. Two silicon substrates (purchased products) were fixed to the deposition plate. Pressure at the start of deposition: 4.49 × 10 －３ A thin film of DPBPhe was formed on each substrate by vapor deposition of DPBPhe under the conditions of 2 Pa, a current of 25 A, and a shutter open time of 0 to 90 seconds.

[0080] Next, an electron beam lithography system is used to irradiate the material with a radiation beam of 100 to 6000 μC / cm ２ The thin film of DPBPhe was irradiated with an electron beam at an exposure dose of 1000 u / s. The substrate with the thin film after electron beam irradiation was then immersed in hexane or ethyl acetate for 30 or 60 seconds as development. The substrate with the developed thin film was dried, and the surface of the thin film was observed using an optical microscope. It was confirmed that for both silicon substrates, EB irradiation of the thin film of DPBPhe allowed relatively good pattern formation in the thin film of DPBPhe.

[0081] (Example 4) As in Example 1, a thin film of commercially available 10,12-pentacosadienoic acid (DPcA) (molecular weight (MW): 374.60 / melting point (mp): 63-65°C) was prepared using a small vacuum deposition apparatus. Specifically, 7.8 mg of DPcA was placed on a tungsten boat. Silicon substrates (silicon substrates cleaned with Semicoclean 23 and silicon substrates treated with HMDS) were fixed to the deposition plate. Pressure at the start of deposition: 3.54 x 10 －３ The deposition of DPcA was carried out under the conditions of a vacuum of 10 Pa, a current of 20 A, and a shutter open time of 70 seconds.

[0082] Next, an electron beam lithography system is used to irradiate the material with a radiation intensity of 40 to 6000 μC / cm ２ The DPcA thin film was irradiated with an electron beam at an exposure dose of 1000 u / s. The substrate with the thin film after electron beam irradiation was then immersed in hexane for 60 seconds as development. The substrate with the developed thin film was dried, and the surface of the thin film was observed under an optical microscope. It was confirmed that it was possible to form a pattern on the DPcA thin film by irradiating it with EB for both the silicon substrate cleaned with Semicoclean 23 and the silicon substrate treated with HMDS. No difference was observed between the silicon substrate cleaned with Semicoclean 23 and the silicon substrate treated with HMDS.

[0083] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims.

[0084] Furthermore, the following supplementary notes are disclosed regarding the above-described embodiment.

[0085] (Supplementary Note 1) A pattern formation method comprising: a film formation step of depositing a substance containing a diacetylene derivative on a substrate to form a film of the substance containing the diacetylene derivative on the substrate; a polymerization step of inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film of the substance containing the diacetylene derivative to produce a polymer of the diacetylene derivative on the substrate; and a removal step of removing the film of the substance containing the diacetylene derivative formed on the substrate to form a pattern of the polymer of the diacetylene derivative on the substrate. (Supplementary Note 2) The pattern formation method according to Supplementary Note 1, wherein the polymerization step comprises inducing a polymerization reaction of the diacetylene derivative by irradiating at least a portion of the film of the substance containing the diacetylene derivative with extreme ultraviolet light. (Supplementary Note 3) The pattern formation method according to Supplementary Note 1, wherein the polymerization step comprises inducing a polymerization reaction of the diacetylene derivative by irradiating at least a portion of the film of the substance containing the diacetylene derivative with an electron beam. (Appendix 4) The pattern formation method according to any one of Appendices 1 to 3, wherein the diacetylene derivative is a symmetric diacetylene derivative. (Appendix 5) The pattern formation method according to any one of Appendices 1 to 4, wherein a substituent in the diacetylene derivative includes a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted acyloxy group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group. (Appendix 6) The pattern formation method according to any one of Appendices 1 to 5, wherein the number of carbon atoms contained in the substituent in the diacetylene derivative is 1 or more and 30 or less. (Appendix 7) The pattern formation method according to any one of Appendices 1 to 6, wherein the substituent in the diacetylene derivative includes an arylene group.

[0086] 10 Substrate 20 Film of material containing diacetylene derivative 30 Polymer of diacetylene derivative

Claims

1. A pattern forming method comprising: a film forming step of forming a film of a material containing a diacetylene derivative on a substrate by attaching the material to the substrate; a polymerization step of producing a polymer of the diacetylene derivative on the substrate by inducing a polymerization reaction of the diacetylene derivative in at least a portion of the film of the material containing the diacetylene derivative; and a removal step of forming a pattern of the polymer of the diacetylene derivative on the substrate by removing the film of the material containing the diacetylene derivative formed on the substrate.

2. The pattern formation method according to claim 1, wherein the polymerization step includes irradiating extreme ultraviolet light onto at least a portion of a film of a substance containing the diacetylene derivative, thereby inducing a polymerization reaction of the diacetylene derivative.

3. The pattern formation method according to claim 1, wherein the polymerization step includes irradiating at least a portion of the film of the material containing the diacetylene derivative with an electron beam to induce a polymerization reaction of the diacetylene derivative.

4. The pattern formation method according to claim 1, wherein the diacetylene derivative is a symmetric diacetylene derivative.

5. The pattern formation method according to claim 1, wherein the substituent in the diacetylene derivative includes a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted acyloxy group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group.

6. The pattern formation method according to claim 1, wherein the number of carbon atoms contained in the substituent in the diacetylene derivative is 1 or more and 30 or less.

7. The pattern formation method according to claim 1, wherein the substituent in the diacetylene derivative includes an arylene group.

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