JPS6233737B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a fine pattern forming method that utilizes a vapor phase graft polymerization method to directly form an arbitrary resist pattern for high-precision microfabrication on a substrate to be processed. (Prior art) Conventionally, in the manufacture of ICs, LSIs, etc., a resist made of a polymer compound, etc. is applied on the surface of the substrate to be processed to form a film, and this is exposed to ultraviolet rays, deep ultraviolet rays, and X-rays.
High-energy beams such as beams and electron beams are irradiated in a pattern to form a latent image through chemical changes in the resist film, and then developed to obtain a patterned resist film, which is used to process the surface of the substrate to be processed. I'm going. With the miniaturization of pattern dimensions of ISI elements in recent years, resist materials used for pattern formation are required to have high sensitivity and resolution to energy rays as well as high resistance to dry etching during substrate processing. This is because conventional wet chemical etching using an etchant has low processing accuracy, and in recent years, dry etching has come to be used for etching substrates. However, the sensitivity, resolution, and dry etching resistance of resist materials tend to be contradictory to each other, and no material has been obtained that satisfies all of the properties. Another important problem with the miniaturization of LSI devices is that as the dimensions of the device wiring become smaller, the wiring resistance increases, making it impossible to increase the speed of the device.
There is a demand for larger wiring layers, which creates a considerable level difference on the surface of the processed substrate. To process such a substrate surface, it is necessary to use a fairly thick resist layer. However, the use of thicker resist layers generally results in lower resolution. This is particularly the case when a negative type resist that utilizes a crosslinking reaction is used, and this is because the resist in the crosslinked portions swells during wet development such as spray development or solvent immersion. However, in the currently used method of drawing LSI device patterns directly onto a wafer by scanning an electron beam or ion beam, it is often more efficient to use a negative type. In addition, with the wet development method, in addition to a decrease in resolution, the yield of device manufacturing decreases due to the occurrence of pinholes due to partial dissolution of soluble resist components and the occurrence of defects due to dust and impurities mixed in the developing solvent. . Under the above circumstances, in recent years, materials and methods that enable so-called dry development, in which the resist pattern forming process is performed dryly, have been actively researched. GN Taylor and others mix monomers into polydichloropropyl acrylate, which is an organic polymer compound, to react with this polymer when irradiated with high-energy rays to form a resist layer. After irradiation with energy rays, monomers are removed from the resist layer in unirradiated areas by heating the sample under vacuum. After this, plasma etching is performed, and the monomers are graft-polymerized in the irradiated areas. reported that the etching rate was considerably slower than that of the unirradiated area, making it possible to form a pattern [Journal of the Electrochemical Society].
the Electrochemical Society, Vol. 127, p. 2665 (1980), and the Journal of Baquium Science and Technology (1980).
Vacuum Science and Technology) Volume 19, No.
See page 872 (1981)]. Many other methods have been published that combine dry etching with the removal of low-molecular-weight compounds by heating under vacuum, similar to the method of Taylor et al. Since the base polymer material layer is the same, a sufficiently high selectivity cannot be achieved in the etching rate during dry etching development, resulting in a large film loss in the irradiated area. With a completely different idea from these methods, Harada et al. proposed a method of directly forming a pattern by a dry process in Japanese Patent Application No. 184495/1983. In this method, active points are created by irradiating a base material coated on the surface of the substrate to be processed with high-energy rays in a pattern, and a monomer gas capable of addition polymerization is introduced onto this film to form the irradiated part of the pattern. This is a method in which a pattern is directly formed in a dry process by selective graft polymerization, and the pattern is formed by removing the base film by dry etching using the thus obtained graft polymer film pattern. In the method of Harada et al., a polymer material layer that is easily dry-etched, such as polymethyl methacrylate, is used as the base film, and a polymer material layer that is difficult to dry-etch, such as polystyrene, is used as the graft polymer film layer. This method attempts to utilize the difference in etching speed, and since the graft polymer film layer and the base material film layer can be made of completely different polymer materials, it is easy to take advantage of the difference in etching speed. Using this method, Harada et al. graft polymerized monomers such as styrene and methyl methacrylate onto a base film made of organic polymer materials such as polymethyl methacrylate, polyisopropenyl ketone, polyvinylidene chloride, and polyvinylidene fluoride. proposed. However, since both the base film and the graft polymer film are polymers of hydrocarbon-based unsaturated compounds, a sufficiently high etching selectivity cannot be obtained. Therefore, in order to thicken the base film layer and create a resist pattern with a good shape ratio, the thickness of the graft polymer film must also be made considerably thicker, and the amount of high-energy radiation irradiated to the pattern area also increases. In addition, it is necessary to lengthen the graft polymerization treatment time. Moreover, since graft polymerization has no directionality, as the film thickness increases, the line width also increases accordingly, causing a decrease in resolution.
Furthermore, since graft polymerization progresses laterally not only on the surface of the substrate but also in the substrate film, this also causes a decrease in resolution. To solve these problems, Tamamura et al. used a two-layer base film, the lower layer consisting of an organic polymer material layer and the upper layer consisting of a silicone resin, and irradiated the upper layer silicone resin. A graft polymer film in the shape of a pattern is formed, and using this graft polymer film as a mask, the silicone resin in the area not covered by the graft polymer film is etched away, and then the silicone resin in the area not covered by the silicone resin is etched away. We proposed a method for forming fine patterns by etching away organic polymer material layers. (Patent Application No. 57-59612) According to this method, even if a very thin silicone resin layer is used, a pattern can be transferred to a relatively thick organic polymer material layer, which is necessary for etching the silicone resin layer. Furthermore, the graft polymer film used as a mask may also be thin. Therefore, it not only improves the decrease in resolution caused by increasing the thickness of the graft polymer film, but also reduces the amount of high-energy ray irradiation, that is, increases sensitivity, and shortens graft polymerization processing time. be. However, general silicone resins, especially room-temperature-curable, two-dimensionally cross-linked silicone rubber, expand when exposed to high-energy rays, causing problems such as wrinkles around the irradiated area and significantly reducing resolution. There are drawbacks. In addition, when using a three-dimensionally crosslinked silicone resin that does not cause expansion, the production of active sites is extremely small, and therefore it is necessary to increase the irradiation dose and lengthen the grafting time, which significantly reduces production efficiency. The disadvantage is that it decreases. Furthermore, when linear silicone gum is used, its glass transition temperature is low, so the film has fluidity, which causes a decrease in resolution. (Object of the Invention) The present invention has been made to solve the above-mentioned problems in the method of forming fine patterns, and its purpose is to provide high sensitivity and high resolution without causing expansion and flow of the base film due to high energy ray irradiation. An object of the present invention is to provide a method for forming a fine pattern by imageable vapor phase graft polymerization. Another object of the present invention is to provide a method for forming fine patterns that can reduce the amount of high-energy ray irradiation and has high production efficiency. (Structure of the Invention) To summarize the present invention, the present invention involves forming a film made of a base material that generates active sites capable of initiating addition polymerization by irradiation with high-energy rays on a substrate, and irradiating the film with high-energy rays. In a method of forming a fine pattern by exposing the irradiated film to a monomer gas atmosphere after pattern irradiation and selectively graft polymerizing the pattern irradiated areas to form a pattern-shaped graft polymer film, A fine pattern forming method (first invention) characterized in that a three-dimensionally crosslinked silicone resin having a vinyl group is used as a base material to generate active points capable of initiating addition polymerization by energy ray irradiation, and a high energy A film made of a base material that generates active sites capable of initiating addition polymerization upon irradiation with radiation is formed, and after irradiating the film with a pattern of high-energy rays, the irradiated film is exposed to a monomer gas atmosphere, and the irradiated portion of the pattern is exposed to a monomer gas atmosphere. is selectively graft-polymerized to form a pattern-shaped graft polymer film, and when a fine pattern is formed on a base film by etching using this graft polymer film as a mask, the base film has an organic polymer film as a lower layer. Using a two-layer base film consisting of a molecular material layer and an upper layer consisting of a silicone resin, a graft polymer film in the shape of an irradiation pattern is formed on the upper silicone resin layer,
Using this graft polymer film as a mask, the silicone resin in the area not covered by the graft polymer film is etched away, and the organic polymer material layer in the area not covered by this silicone resin is further etched away. A fine pattern forming method (second method) characterized in that a three-dimensionally crosslinked silicone resin having a vinyl group is used as the upper layer silicone resin
invention). In addition, the present invention can be used as a base film in a fine pattern forming method that utilizes conventional high-energy ray irradiation to generate active points capable of initiating addition polymerization in a base film and vapor phase graft polymerization. It is a three-dimensional cross-linked type that generates a silicone resin with vinyl groups that efficiently generates active sites without expanding when irradiated with high-energy rays, and can initiate graft polymerization in a monomer gas atmosphere. This is based on the discovery that when the film has two layers, the underlying organic polymer material layer is hardly etched by dry etching using oxygen gas, which has a high etching rate. Conventional three-dimensional cross-linked silicone resins have many -Si-O- bonds that are relatively stable against high-energy ray irradiation, so active points are generated by high-energy ray irradiation, and patterns can be created by graft polymerization to these. It is considered to be less sensitive to the formation method, and there have been no examples of its use, and the possibility of its use was unknown. According to the present invention, if a three-dimensionally crosslinked silicone resin having a vinyl group is used, expansion of the silicone resin film due to high energy ray irradiation can be suppressed by three-dimensionally crosslinking.
Moreover, since it has a vinyl group, which is a typical unsaturated hydrocarbon group, active points are generated very efficiently by high-energy ray irradiation. Moreover, since it is three-dimensionally crosslinked, it has a high glass transition temperature and does not suffer from a drop in resolution due to flow, unlike silicone rubber materials. Therefore, it has a great effect on improving resolution and shortening working time by shortening irradiation time and grafting time. Furthermore, the silicone resin of the present invention is very fluid during film formation, and hardens immediately after formation, so it has the advantage that pinholes are less likely to form even if the film is made thin. Next, the present invention will be specifically described with reference to the accompanying drawings. FIG. 1 is a process diagram showing a specific example of pattern formation according to the first invention of the present invention, in which a is a step of forming a base film on a substrate to be processed, and b is a process of forming a desired base film of a. step of irradiating the pattern area with high-energy rays, c is a step of exposing the irradiated base film of b to a monomer gas atmosphere to form a graft polymer film, and d is a step of forming a graft polymer film obtained by steps a, b, and c. 1 represents a graft polymer film pattern, where 1 is a substrate to be processed, 2 is a base film, 3 is a high energy beam, 4 is a monomer gas atmosphere, and 5 is a graft polymer film. In implementation, first, a three-dimensionally crosslinked silicone resin having a vinyl group is applied onto a substrate 1 such as a silicone wafer whose surface has been thermally oxidized to form a base film 2 (step a), and then, High-energy rays 3 such as electron beams, X-rays, and far ultraviolet rays are irradiated onto the desired pattern area of the base film 2 of step a (step b). In this step, active points capable of initiating addition polymerization are generated in the high-energy ray irradiated portion of the base film 2. Next, the irradiated base material film obtained in step b is exposed to a predetermined monomer gas atmosphere 4 to selectively graft polymerize the pattern irradiated areas to form a pattern-shaped graft polymer film 5 (step c). . Graft polymerization occurs at a portion where the high energy beam 3 is irradiated and active sites capable of initiating addition polymerization are generated. After going through this process,
The desired graft polymer film pattern is obtained by removing the monomer gas atmosphere (step d).
Note that although the base film 2 in the unirradiated area in d is removed by dry etching in the next step (not shown), the film thickness of the graft polymer film pattern in the irradiated area does not decrease at all due to dry etching. Even if it occurs, the amount is extremely small. Next, FIG. 2 is a process diagram showing a specific example of fine pattern formation according to the second aspect of the present invention. Step a is coating an organic polymer material layer, b is coating a silicone resin layer, c is irradiation with high energy rays, d is graft polymerization by introducing a monomer gas capable of addition polymerization, and e is graft polymer film. Etching of silicone resin layer using pattern as mask, f
indicates etching of the organic polymer material layer using the silicone resin layer as a mask, g indicates etching of the substrate to be processed, and g' indicates doping of the substrate to be processed. Thus, reference numeral 11 is a substrate to be processed, 12 is an organic polymer material layer, 13 is a silicone resin layer, and 14 is a silicone resin layer.
15 is a monomer gas for graft polymerization, 16 is a graft polymer film, and 17 is a dopant. First, a relatively thick organic polymer material layer 12 having a thickness of approximately 1 μm is applied to the surface of the substrate 11 to be processed (step a). On top of this, a relatively thin silicone resin layer 13 of about 0.1 μm is applied (step b). The substrate having the two-layer film thus obtained is irradiated with high-energy rays 14 in an arbitrary pattern (step c). As the high energy beam, electron beams, X-rays, ion beams, deep ultraviolet rays, etc. can be used. The thus irradiated substrate is placed in an atmosphere of a monomer gas 15 capable of addition polymerization without being brought into contact with air, and the monomer is selectively graft-polymerized on the irradiated area to form a graft polymer film 16 pattern. (Step d). After irradiation, a pattern can be formed by taking the substrate out into the air and performing graft polymerization, but a large amount of irradiation is required and the sensitivity is reduced. The thickness of the graft polymer film can be increased by increasing the irradiation dose and lengthening the graft polymerization time, but it is not sufficient to remove the silicone resin in the upper layer of the base layer by dry etching. It is sufficient to deposit a certain thickness. silicone resin layer, 0.1μm
In terms of thickness, the graft polymer film thickness is 0.2μm
It is enough. Next, using this graft polymer film pattern as a mask, the area not covered by the graft polymer film, that is, the unirradiated portion of the silicone resin layer is removed by dry etching (step e). As the etching gas, one is selected that etches the silicone resin more quickly than the graft polymer film layer, usually a gas based on CF ₄ and CHF ₃ . Using the thus obtained patterned silicone resin layer as a mask, the organic polymer material layer in the unirradiated area is removed by dry etching (step f). As the etching gas at this time, a gas that etches the silicone resin layer more slowly than the organic polymer material layer is selected, usually oxygen gas. In this way, a thin graft polymer film can be used to form a pattern in a relatively thick layer of organic polymeric material. Thereafter, using this patterned organic polymer material layer, the surface of the underlying substrate to be processed is etched (step g) or doped (step g'). The monomer gas to be graft-polymerized includes organic monomers that have addition polymerization ability and can be gasified.
For example, styrene, divinylbenzene, vinyltoluene, acrylonitrile, methyl methacrylate, methacrylic acid, methyl acrylate, maleimide, etc. can be used. The silicone resin may be any silicone resin that is three-dimensionally crosslinked and has a nyl group, such as a composition in which vinyltriethoxysilane is mixed with a dimethylsiloxane oligomer that has hydroxyl groups at both ends, or a composition in which an alkoxy group is introduced. Polyvinylmethylsiloxane with a three-dimensional skeleton modified so that it can be cured by moisture in the air, a composition in which a platinum catalyst is added to a vinylmethylsiloxane oligomer with hydrogen terminals, vinylmethyldiethoxysilane, dimethyldiethoxy A reaction product obtained by reacting silane and methyltriethoxysilane,
Examples include compositions in which a three-dimensionally crosslinked silicone resin is mixed with polyvinylmethylsiloxane, and therefore silicone resin compositions that generate three-dimensional crosslinks at the stage of coating on a substrate to be processed to form a film may also be used. In the second invention, the organic polymer material film used as the lower layer of the base two-layer film can be made of any material in principle as long as it does not dissolve in the coating solution used to apply the silicone resin layer, but In this case, a material with high resistance to dry etching against reactive gases other than oxygen gas is used, and a material that is less likely to introduce impurities into the substrate to be processed, that is, a material that can be applied to semiconductor processing processes is used. Among them, polyamide-imides and polyimide films made from them are the most suitable as they are insoluble in most organic solvents and have high heat resistance and processing resistance, but other AZ-based photoresists, acrylic acid, Copolymers of methacrylic acid and aromatic esters of these acids, polystyrene, etc. can be used. Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples, and a wide range of combinations of material systems are possible. Example 1 A 10% xylene-ligroin mixed solution (mixing ratio 1:1) of a resin obtained by hydrolyzing 8 parts of dimethyldiethoxysilane, 6 parts of methyltriethoxysilane, and 1 part of vinylmethyldiethoxysilane was prepared. did. Next, the solution was applied onto a silicon substrate by a spin coating method to form a 0.4 μm thick vinyl group-containing silicone resin film. Next, using an electron beam exposure device, a line pattern with a width of 5 μm was irradiated with various exposure doses at an accelerating voltage of 20 KV. After that, the sample was moved to a vacuum atmosphere of 10 ^-3 Torr without contact with air, and styrene monomer gas purified and degassed at a gas pressure of 3 Torr was introduced, and the sample was left for 1 hour to be transferred to the irradiation section. Graft polymerization was carried out. Microscopic observation revealed that a uniform and glossy graft polymerized polystyrene film was obtained in the irradiated area, and no increase in film thickness was observed in the non-irradiated area. The amount of electron beam irradiation required to obtain a graft polymerized polystyrene film with a thickness of approximately 0.2 μm is approximately 10 μm.
It was mC/ ^cm2 . After heating this sample in air at 150°C for 30 minutes, using carbon tetrafluoride gas to which 20% hydrogen gas was added,
That is, the silicone resin in the non-irradiated area was removed by reactive sputter etching. The etching rate ratio of the graft polymerized polystyrene and silicone resin at this time was about 1:3, and the silicone resin with a thickness of 0.4 μm could be removed by etching using the graft polymerized polystyrene film with a thickness of 0.2 μm as a mask. Examples 2 to 6 Five pieces of silicone resin coated with a film thickness of 0.4 μm on silicon substrates were prepared in the same manner as in Example 1, and after irradiating with an electron beam in the same manner as in Example 1, each substrate was coated with silicone resin. The material was quickly transferred to an oxygen-free vacuum atmosphere to avoid contact with oxygen. The base film thus transferred to a vacuum atmosphere was given an atmosphere of various monomer gases capable of addition polymerization.
methyl methacrylate (Example 2), methyl acrylate (Example 3), acrylonitrile (Example 4), divinylbenzene (Example 5), and maleimide (Example 6) were introduced at a pressure of When the graft polymerization was carried out after being left for 1 hour, a uniform and glossy graft polymer film was obtained only in the irradiated areas in all cases. Table 1 shows the amount of electron beam irradiation required to make the graft polymer film thickness 0.2 μm.
It was shown to.

【table】

[Table] Examples 7 to 10 As a vinyl group-containing silicone resin, a silicone resin (Example 7) in which a dimethylsiloxane oligomer (molecular weight approximately 1200) having hydroxyl groups at both ends was reacted with vinyltriethoxysilane, and a silicone resin containing a methoxy group as a side chain. Polyvinylmethylsiloxane (Example 8) containing 20% of polyvinylmethylsiloxane (Example 8), silicone resin made three-dimensional by adding a platinum catalyst to a vinylmethylsiloxane oligomer (molecular weight approximately 2000) with hydrogen at both ends (Example 9), three-dimensional crosslinking Example 1 except that a silicone resin (Example 10) obtained by mixing 5% by weight of vinyl group-containing silicone rubber (SH410, manufactured by Toray Silicone) with molded silicone resin (SR2410, manufactured by Toray Silicone) was used. A pattern was formed by graft polymerization under the same conditions. At this time, the amount of electron beam irradiation required to make the graft polymer film 0.2 μm thick was as shown in Table 2.

【table】

[Table] Examples 11 to 13 Three samples were prepared by coating and drying silicone resin on a silicon substrate using the method of Example 1, and using a 400-mesh copper mesh as a mask, Cu-L wire (13.3 Å) X-rays (Example 11),
Far ultraviolet rays using a 500W Xe-Hg lamp (example)
12), the sample was irradiated with an ion beam (Example 13) with an accelerating voltage of 34 KV from a liquid Ga ion source, and the sample was moved under a vacuum of 10 ^-3 Torr without contact with air, and then placed in a styrene gas of 3 Torr. was introduced and graft polymerization was carried out for 1 hour. As a result, a uniform and glossy graft polymer film pattern was obtained in the irradiated area in all samples. Table 3 shows the irradiation amount of each energy beam necessary for the graft polymer film to have a thickness of 0.2 μm in 1 hour of graft polymerization time.

[Table] Example 14 A substrate to be processed having a silicone resin base film prepared by the method of Example 1 was exposed using an electron beam exposure device.
0.5μm width, 1μm width, 2μm width, 5μm width 4
The line pattern of seeds was irradiated with a 20KV electron beam. After that, the sample was moved to a vacuum of 10 ^-3 Torr without coming into contact with air, 3 Torr of styrene monomer gas was introduced, and graft polymerization was carried out for 1 hour.
A uniform graft-polymerized polystyrene film was obtained in each pattern. Table 4 shows the electron beam irradiation amount at which a 0.2 μm thick graft polymerized polystyrene film was obtained for each pattern size and the line width of the graft polymer film pattern at this time.

[Table] Example 15 A varnish of polyamic acid (manufactured by DuPont, PI2500) is applied to a thickness of 1.1 μm by spin coating on a thermally oxidized silicon substrate. This film is
It was heated at 300° C. for 1 hour to form a polyimide film with a thickness of about 0.9 μm. On top of this, 0.1% of the vinyl group-containing silicone resin used in Example 1 was applied by spin coating.
Coat to a thickness of μm. After drying at 100 °C for 30 minutes under nitrogen flow, using an electron beam exposure device
A line pattern with a width of 5 μm was irradiated with various exposure doses at an accelerating voltage of 20 KV. After that, the sample was moved to a vacuum atmosphere of 10 ^-3 Torr without contact with air, and styrene monomer gas purified and degassed at a gas pressure of 3 Torr was introduced, and the sample was left for 1 hour to be transferred to the irradiation section. Graft polymerization was carried out. Microscopic observation revealed that a uniform and glossy graft polymerized polystyrene film was obtained in the irradiated area, and no increase in film thickness was observed in the non-irradiated area. The amount of electron beam irradiation required to obtain a graft polymerized polystyrene film with a thickness of approximately 0.2 μm is:
It was about 10 μC/cm ² . This sample was heated in air at 150°C for 30 minutes, and then heated using carbon tetrafluoride gas to which 10% hydrogen gas was added.
That is, the silicone resin film in the non-irradiated area was removed by reactive sputter etching. The reactive sputter etching rate ratio of the graft polymerized polystyrene film using carbon tetrafluoride gas added with 10% hydrogen gas and the silicone resin film is approximately 1:1.3, and the 0.1 μm thick silicone resin film is replaced with the 0.2 μm thick silicone resin film. The graft polymerized polystyrene film was used as a mask to remove the film by etching. Next, the polyimide film in the area not covered with the silicone resin film was removed by reactive sputter etching using oxygen gas. The sputter etching rate ratio at a pressure of 0.03 Torr and an oxygen gas flow rate of 5 C.C./min was approximately 40:1 for the polyimide film and the silicone resin film. Therefore, even after the 0.9 μm thick polyimide film in the unirradiated area was completely etched, almost no film reduction was observed in the irradiated area. In this way, a pattern could be transferred from a 0.2 μm thick graft polymer film to a 0.9 μm thick polyimide film. Using this 0.9 μm thick polyimide film, a thermally oxidized silicon layer, which is a substrate to be processed, was subjected to reactive sputter etching with carbon tetrafluoride added with 10% hydrogen gas to produce a silicon oxide pattern with a depth of 1 μm. Examples 16-20 Polyimide films (0.9
A graft polymer film was formed on a two-layer base film of a silicone resin film (0.1 μm) and a silicone resin film (0.1 μm) using various monomers in the same manner as in Examples 1 to 6. 0.2
The amount of electron beam irradiation required to form a .mu.m graft polymer film was as shown in Table 5.

[Table] After that, the silicone resin was etched by the method of Example 15, and then the polyimide film was etched, and in all samples, the pattern of the graft polymer film could be transferred to the polyimide film. Example 21 When the silicone resins of Examples 7 to 10 were used as the silicone resin in the method of Example 15, the pattern of the graft polymer film could be transferred to the polyimide film in the same manner as in Example 15. . Example 22 Using the method of Example 15, the electron beam irradiation amount was set to 4, 7,
After drawing line patterns of 0.3, 0.5, 0.7, and 1.0 μm at 10 and 20 μC/cm ² , graft polymerization and dry etching were performed in the same manner as in Example 15. The line widths were as shown in Table 6.

[Table] Comparative Example 1 In Example 1, using only the three-dimensional crosslinked silicone rubber (SR2410 manufactured by Toray Silicone), the electron beam required to obtain a graft polymerized polymethyl methacrylate film with a thickness of approximately 0.2 μm was obtained. The irradiation dose was approximately 300 μC/cm ² . Comparative Example 2 When a room temperature curing silicone rubber (TSE3032 manufactured by Toshiba Silicone Co., Ltd.) was used in Example 1, only the electron beam irradiated area expanded and graft polymerization could not be carried out. Comparative Example 3 In Example 14, when the resolution was measured using vinyl group-containing polydimethylsiloxane (SH-410 manufactured by Toray Silicone Co., Ltd.), which is a silicone rubber, the irradiation line width was 0.5, 1, 2, and 5 μm, respectively.
On the other hand, the line width of the graft polymer film is 0.7μm,
They became 1.2μm, 2.5μm, and 6.0μm. From the comparison between the Examples and Comparative Examples, it can be seen that the silicone resin of the present invention exhibits effects as a base film that cannot be predicted from other silicone resins. (Effects of the Invention) As is clear from the above description, when irradiating a base film provided on a substrate to be processed with high-energy rays and selectively forming a graft polymer film pattern in the irradiated area, When the base film has one layer, a three-dimensionally crosslinked silicone resin having a vinyl group is used as the base material, and when the base film has two layers, a relatively thick general organic polymer is used as the lower layer. By providing a molecular material layer and a relatively thin layer of the silicone resin on top, it is possible to form a graft polymer film with high sensitivity and less deterioration in resolution.
This has a significant effect on increasing the density of LSI and improving work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing a specific example of pattern formation according to the first invention, and FIG. 2 is a process diagram showing a specific example of pattern formation according to the second invention. In FIG. 1, 1...substrate to be processed, 2...base film, 3...
High energy ray, 4...monomer gas atmosphere, 5...graft polymer film. In Fig. 2, 11...substrate to be processed;
12... Organic polymer material layer, 13... Silicone resin layer, 14... High energy ray, 15... Monomer gas,
16... Graft polymer film, 17... Dopant.

Claims (1)

[Claims] 1. A film made of a base material that generates active points capable of initiating addition polymerization by irradiation with high-energy rays is formed on a substrate, and after irradiating the film with high-energy rays in a pattern, the irradiated film is In a method of forming a fine pattern by exposing to a monomer gas atmosphere and selectively graft polymerizing the irradiated areas of the pattern to form a pattern-shaped graft polymer film, addition polymerization can be initiated by high-energy ray irradiation. A fine pattern forming method characterized by using a three-dimensionally crosslinked silicone resin having a vinyl group as a base material for generating active points. 2. A film made of a base material that generates active points capable of initiating addition polymerization by irradiation with high-energy rays is formed on a substrate, and after irradiating the film with high-energy rays in a pattern, the irradiated film is placed in a monomer gas atmosphere. When a pattern-shaped graft polymer film is formed by exposing and selectively graft polymerizing the pattern irradiated areas, and a fine pattern is formed on the base film by etching using this graft polymer film as a mask, the base film In this method, a graft polymer film in the shape of an irradiation pattern is formed on the upper silicone resin layer using a two-layer base film, the lower layer of which is an organic polymer material layer and the upper layer of which is a silicone resin. Using the combined film as a mask, the silicone resin in areas not covered by the graft polymer film is removed by etching.
Furthermore, in this method of forming a fine pattern by etching and removing the organic polymer material layer in the area not covered with the silicone resin, it is possible to use a three-dimensionally crosslinked silicone resin having a vinyl group as the upper layer silicone resin. Characteristic fine pattern formation method.