JP5555111B2 - Polymer thin film having silsesquioxane, microstructure and production method thereof - Google Patents

Description

  The present invention relates to a polymer thin film having a microstructure formed by microphase separation of a polymer block copolymer having silsesquioxane on a substrate, a microstructure obtained using the polymer thin film, And a manufacturing method thereof.

In recent years, with the miniaturization and high performance of electronic devices, energy storage devices, sensors, and the like, there is an increasing need to form a fine regular array pattern having a size of several nanometers to several hundred nanometers on a substrate. Therefore, establishment of a process capable of manufacturing a fine regular array pattern (hereinafter simply referred to as “fine structure”) with high accuracy and low cost is required.
As a processing method of such a fine structure, a top-down method represented by lithography, that is, a method of finely engraving a bulk material is generally used. For example, photolithography used for semiconductor microfabrication such as LSI manufacturing is a typical example.

  However, such a top-down approach increases the manufacturing cost by increasing the size of the apparatus and the complexity of the process as the fineness of the fine structure increases. In particular, when the processing size of the fine structure becomes as fine as several tens of nanometers, it is necessary to use an electron beam or deep ultraviolet rays for patterning, and a huge investment is required for the apparatus. In addition, if it becomes difficult to form a fine structure using a mask, the direct drawing method must be applied, which causes a problem that the processing throughput is significantly reduced.

  Under such circumstances, a process that applies a phenomenon in which a substance naturally forms a structure, that is, a so-called self-organization phenomenon, attracts attention. In particular, the process using microphase separation of the polymer block copolymer is an excellent process in that it can form microstructures having various shapes of several tens to several hundreds of nanometers by a simple coating process. . For example, when different types of polymer segments in the polymer block copolymer do not mix with each other (incompatible), these polymer segments are separated into microspheres by separating them into a spherical or columnar shape in the continuous phase. A structure in which layered microdomains are regularly arranged is formed.

  As a method for forming a microstructure using this microphase separation, for example, a thin film of a polymer block copolymer composed of a combination of polystyrene and polybutadiene, polystyrene and polyisoprene, polystyrene and polymethyl methacrylate, or the like is formed on a substrate. A technique for forming holes and lines and spaces having shapes corresponding to the microdomains of the thin film on the substrate by performing microphase separation and etching the substrate using the thin film as a mask.

  In addition, in the technology for microphase separation of the polymer block copolymer applied on the substrate, regions having different chemical properties are formed in a fine pattern on the surface of the substrate, and the substrate surface and the polymer block copolymer are formed. There is known a chemical registration method in which the arrangement of microdomains is controlled by utilizing the difference in chemical interaction with (see, for example, Patent Document 1 and Patent Document 2).

  This chemical registration method uses a top-down method in advance so that the surface of the substrate is a region having different wettability with respect to each block chain (polymer segment) constituting the polymer block copolymer. It is to be chemically patterned. More specifically, for example, in the chemical registration method for microphase separation of a polystyrene / polymethylmethacrylate diblock copolymer, the surface of the substrate has a region having a good affinity for polystyrene (large region), It is chemically patterned by dividing it into regions having good affinity with polymethylmethacrylate. At this time, by setting the pattern shape and the pattern interval to a shape corresponding to the microphase separation structure of the polystyrene-polymethylmethacrylate diblock copolymer, the region having good affinity (wetability) with polystyrene is made of polystyrene. A microdomain made of polymethyl methacrylate is arranged in a region having good affinity (wetting property) with polymethyl methacrylate.

  According to such a chemical registration method, in order to form a chemical pattern by a top-down method, the long-range order of the obtained pattern is ensured by a top-down method, and regularity over a wide range. A fine structure with excellent and few defects can be formed. Furthermore, even if the pattern spacing is kept in the shape corresponding to the microphase separation structure, even if the density of the pattern is reduced, a microdomain made of polystyrene is arranged in a region having good affinity (wetability) with polystyrene. Since the microphase separation structure is maintained between the pattern and the pattern, a microdomain structure is arranged (pattern interpolation).

By the way, in recent years, a microphase-separated structure whose size is further miniaturized is desired because of a demand for further miniaturization and higher performance of electronic devices and the like.
However, when the chemical phase registration method is used to form a microphase-separated structure of polystyrene-polymethylmethacrylate diblock copolymer, the interaction parameter of this copolymer is so small that it is less than 10 nanometers or less. There is a problem that a micro phase separation structure of size cannot be obtained.

  On the other hand, as a polymer block copolymer in which microdomains are oriented in a continuous phase in a direction standing upright with respect to the surface of the substrate (thickness direction of the thin film) and regularly arranged, polyhedral oligo Polymethylmethacrylate-block-POSS-containing polymethacrylate copolymer and polystyrene-block-POSS-containing polymethacrylate copolymer having merlic silsesquioxane (hereinafter sometimes abbreviated as POSS) in the side chain Is known (see, for example, Non-Patent Document 1).

  Since the polymer block copolymer containing a siloxane bond has a larger interaction parameter than the polystyrene / polymethylmethacrylate diblock copolymer, it is considered that the micro phase separation structure can be further refined.

  By the way, there is no regular structure in the thin film when the polymer block copolymer is applied to the surface of the substrate to form a film. This is because the microphase separation process of the polymer block copolymer is frozen because the solvent rapidly evaporates during film formation. Therefore, in order to form a regular self-organized structure, it is necessary to anneal the polymer chains so that they can freely move after film formation. In general, the annealing treatment includes a thermal annealing method and a solvent annealing method.

The thermal annealing method is performed when the glass transition temperature (Tg) of the polymer block copolymer is below the thermal decomposition temperature of the polymer chain constituting the polymer block copolymer and is in an experimentally reachable temperature range. In this method, the polymer block copolymer (thin film) on the substrate is maintained at a temperature equal to or higher than its glass transition temperature (Tg).
Also, the solvent annealing method gives the polymer chain freedom of movement by exposing the polymer block copolymer (thin film) on the substrate to solvent vapor and swelling the polymer block copolymer (thin film). , A way to promote self-organization.

US Pat. No. 6,746,825 US Pat. No. 6,926,953

Macromolecules 2009, 42, 8835-8843

  However, when an attempt is made to form a self-assembled structure of a conventional polymer block copolymer containing a siloxane bond (for example, see Non-Patent Document 1) using a solvent annealing method, the polymer block copolymer (thin film) is formed. Since the self-assembled structure formed by swelling is compressed, the structure may not be maintained well. In addition, since the interval between the arrangement patterns of the self-organized structure varies depending on the swelling state, it may be difficult to control the arrangement of the microdomains using the chemical registration method. In particular, the adverse effect of swelling on the pattern interpolation using the chemical registration method is expected to be significant.

  Therefore, in forming a self-organized structure of a conventional polymer block copolymer containing a siloxane bond (see, for example, Non-Patent Document 1), it is possible to employ a thermal annealing method that can avoid swelling of the thin film. Conceivable.

However, there is no clear glass transition temperature (Tg) in conventional polymer block copolymers containing siloxane bonds. Therefore, it is difficult to perform an appropriate thermal annealing method on the polymer block copolymer (thin film) containing the siloxane bond.
In other words, in the chemical registration method using a conventional polymer block copolymer containing a siloxane bond (see, for example, Non-Patent Document 1), the structure is further miniaturized and has a regularity over a wide range. An excellent structure with few defects cannot be formed on the substrate.

  Accordingly, an object of the present invention is to solve such a problem, and has a structure that is further miniaturized than the conventional one, and has a structure that is excellent in regularity over a wide range and has a structure with few defects. It is to provide a molecular thin film, a fine structure, and a method for producing them.

The present invention for solving the above problems includes a first step of disposing a polymer layer including a polymer block copolymer having at least a first segment and a second segment on a substrate, and microphase separation of the polymer layer. A second step of arranging a plurality of microdomains having the second segment as a component in a continuous phase having the first segment as a component so as to be regularly arranged along a surface direction of the substrate. In the method for producing a polymer thin film, prior to the first step, a chemical modification layer is formed on the substrate so as to correspond to the continuous phase, and the chemical modification is performed so as to correspond to the arrangement of the microdomains. The method further includes a step of forming a pattern portion having a chemical property different from that of the layer, and the second step includes a step of performing a heat treatment at a specific temperature at which the microphase separation occurs. Click copolymers, and the second segment comprising a polymethylmethacrylate, the main chain of the block copolymer, the formula - (CH ₂₎ n _- alkyl chain represented by (wherein, the Wherein n is an integer satisfying 5 ≦ n ≦ 24), and the first segment containing polymethyl methacrylate having a silsesquioxane skeleton bonded thereto through an organic group containing The functional modification layer is a method for producing a polymer thin film characterized by comprising a polystyrene graft film .

  Further, the present invention for solving the above-described problems includes a step of forming the polymer thin film in which a plurality of the microdomains are arranged in the continuous phase on the substrate by the method for producing the polymer thin film, And a step of removing one of the continuous phase and the microdomain of a molecular thin film.

  The present invention for solving the above-mentioned problems is a polymer thin film obtained by the method for producing a polymer thin film.

  In addition, the present invention that solves the above-described problems is a fine structure obtained by the method for producing a fine structure.

  Further, the present invention for solving the above-mentioned problems is a magnetic recording medium manufactured by the method for manufacturing a fine structure. That is, the magnetic recording medium of the present invention corresponds to the fine structure in the invention of the fine structure manufacturing method.

  According to the present invention, there are provided a polymer thin film, a microstructure and a manufacturing method thereof having a structure that is further miniaturized than the prior art and having a structure that is excellent in regularity over a wide range and has few defects. be able to.

It is a partial expansion perspective view which has a fracture surface in part for demonstrating the structure of the polymer thin film of this invention. (A)-(f) is process explanatory drawing which patterns the surface (chemical modification layer) of the board | substrate used for formation of the polymer thin film of this invention. (A) And (b) is a schematic diagram which shows the aspect by which the chemically modified layer patterned on the board | substrate is arrange | positioned. (A) And (b) is process explanatory drawing of the manufacturing method of the polymer thin film of this invention. In (a), the second region as a chemical mark is arranged over the entire surface of the substrate so as to be the natural period do of the polymer block copolymer, and the polymer block copolymer formed on the surface of the substrate is arranged. The conceptual diagram which shows the mode at the time of carrying out the micro phase-separation of the thin film of a polymer, (b) is arranged so that the defect rate of the 2nd area | region as a chemical mark may be 25%, and a polymer block copolymer The conceptual diagram which shows the mode at the time of carrying out the micro phase separation of the thin film of this, (c) is arranged so that the defect rate of the 2nd area | region as a chemical mark may be 50%, and is a thin film of a polymer block copolymer FIG. 4D is a conceptual diagram showing a state of microphase separation of the polymer block copolymer, the second region as a chemical mark is arranged so that the defect rate is 75%, and the polymer block copolymer thin film is microscopically arranged. It is a conceptual diagram which shows the mode at the time of making it phase-separate. It is a conceptual diagram which shows the mode of the 1st segment and 2nd segment in the polymer block copolymer used for formation of the polymer thin film of this invention. (A)-(f) is process drawing for demonstrating the manufacturing method of the fine structure obtained using the polymer thin film of this invention. It is a perspective view which shows typically a mode that the polymer block copolymer used for formation of the polymer thin film of this invention formed the lamellar micro phase separation structure by carrying out micro phase separation. It is an X-ray small angle scattering (SAXS) curve of a polymer block copolymer (thin film) subjected to microphase separation used for forming the polymer thin film of the present invention. (A) is a plan view showing a partially enlarged polystyrene graft film, and (b) is an arrangement of regions with different pattern lattice spacings d on the surface of the patterned polystyrene graft film. A plan view schematically showing (c) is a plan view of a diced substrate. It is a schematic diagram (plan view) for explaining the configuration of the magnetic recording medium of the present invention.

Hereinafter, embodiments of the polymer thin film of the present invention will be described in detail with reference to the drawings as appropriate. This polymer thin film is obtained by patterning the surface of a substrate on which a chemically modified layer is formed and microphase separation of a polymer block copolymer on the surface of this substrate by a thermal annealing method. Silsesquioxane in which the polymer block copolymer is bonded to the main chain via a divalent organic group containing a — (CH ₂ ) _n — group (where n is an integer of 5 ≦ n ≦ 24). The main feature is that it contains a skeleton.
Below, it demonstrates in order of the polymer thin film, the manufacturing method of this polymer thin film, the microstructure obtained using this polymer thin film, and the manufacturing method of this microstructure.

(Polymer thin film)
As shown in FIG. 1, the polymer thin film M having a microstructure according to the present embodiment has a microphase separation structure composed of a continuous phase 204 and a columnar (cylindrical) microdomain 203. The polymer block copolymer described later is microphase-separated on the surface of the substrate 201 on which the first region 106 and the second region 107 (see FIG. 2F) are formed (patterned). In FIG. 1, the description of the surface of the patterned substrate 201 (the first region 106 and the second region 107 in FIG. 2F) is omitted.

The microdomains 203 are regularly arranged in the continuous phase 204 along the surface direction of the substrate 201. More specifically, the columnar microdomains 203 oriented in the thickness direction of the polymer thin film M are arranged in a hexagonal close-packed structure along the surface direction of the substrate 201.
Note that the columnar microdomain 203 in the present embodiment is formed so as to penetrate in the thickness direction of the polymer thin film M, but the microdomain 203 may not penetrate the polymer thin film M. . In addition, the arrangement of the microdomains 203 is not limited to the hexagonal close-packed structure, and may be a cubic lattice structure or the like.

Further, as will be described in detail later, the microdomain 203 may be lamellar (layered) or spherical. And it cannot be overemphasized that the shape of the continuous phase 204 can take various shapes corresponding to the various shapes of such a micro domain 203. FIG.
1 is a natural period of the microdomain 203, and is a natural value determined according to the type of the polymer block copolymer to be described later for forming the polymer thin film M. The arrangement interval of the microdomains 203 is determined by the natural period do.

(Manufacturing method of polymer thin film)
Next, a method for producing the polymer thin film M will be described.
Here, as shown in FIG. 1, a manufacturing method (a manufacturing method by a chemical registration method) of the polymer thin film M having a structure in which the columnar microdomain 203 stands upright with respect to the surface of the substrate 201 will be described. 2A to 2F to be referred to next are process explanatory views of a method for patterning the surface of the substrate.

In this manufacturing method, a chemically modified layer 401 is first formed on a substrate 201 as shown in FIG.
In the present embodiment, the substrate 201 is assumed to be made of silicon (Si). As the material of the substrate 201, a fine structure 21 (see FIG. 7B), which will be described later, and a fine structure are used. Depending on the application of 21a (see FIG. 7D), for example, inorganic materials such as glass and titania, semiconductors such as GaAs, metals such as copper, tantalum and titanium, and organic materials such as epoxy resins and polyimides The thing which consists of is mentioned.

  As a method for forming the chemically modified layer 401, a functional group serving as a polymerization initiation base point is first introduced into the surface of the substrate 201 by a coupling method or the like, and a polymer is polymerized from the polymerization initiation point. There is a method of synthesizing a polymer having a functional group chemically coupled to the surface in the terminal or main chain and then coupling the polymer to the surface of the substrate 201. In particular, the latter method is simple and recommended.

Here, a method for forming a chemically modified layer 401 made of a polystyrene graft film by coupling polystyrene to the surface of the substrate 201 will be described more specifically.
First, polystyrene having a hydroxyl group at the terminal is synthesized by a predetermined living polymerization. Next, the density of the hydroxyl groups of the natural oxide film formed on the surface of the substrate 201 is increased by exposing the substrate 201 to oxygen plasma or immersing the substrate 201 in a piranha solution. Then, an organic solvent solution such as polystyrene toluene having a hydroxyl group at the terminal is applied onto the substrate 201 to form a film. Thereafter, the substrate 201 is heated at a temperature of about 140 ° C. for about 72 hours in a vacuum atmosphere using a vacuum oven or the like. By this treatment, the hydroxyl group on the surface of the substrate 201 and the hydroxyl group at the end of the polystyrene are dehydrated and condensed, so that polystyrene in the vicinity of the surface of the substrate 201 is bonded to the substrate 201 and chemically modified by a polystyrene graft film on the substrate 201. Layer 401 is formed.

  When polystyrene is grafted onto the surface of the substrate 201, the molecular weight of the polystyrene to be grafted is not particularly limited, but is desirably about 1,000 to 10,000 in terms of number average molecular weight. Polystyrene having a number average molecular weight within such a range can control the thickness of the polystyrene graft film to a suitable level of several nm.

  Next, the chemically modified layer 401 (polystyrene graft film) provided on the surface of the substrate 201 is patterned. As will be described in detail later, the patterning differs in chemical properties from the polystyrene graft film so as to correspond to the arrangement of the microdomains 203 distributed in the continuous phase 204 of the polymer thin film M shown in FIG. It means forming a pattern portion.

As a patterning method, a known patterning technique such as photolithography or an electron beam (EB) drawing method may be applied according to a desired pattern size.
Here, exemplifying a patterning method using photolithography, as shown in FIG. 2B, a resist film 402 is formed on the surface of the chemically modified layer 401 (polystyrene graft film). Next, as shown in FIG. 2C, the resist film 402 is patterned by exposure, and further subjected to development processing, whereby the resist film 402 is formed into a pattern mask as shown in FIG. 2D. Is done.

Then, as shown in FIG. 2 (e), the chemically modified layer 401 is etched by a technique such as oxygen plasma treatment through the resist film 402 formed into a pattern mask. Finally, if the resist film 402 on the remaining chemically modified layer 401 is removed, a chemically modified layer 401 made of a patterned polystyrene graft film is obtained (FIG. 2F). That is, the substrate 201 is divided into a first region 106 made of a chemically modified layer 401 (polystyrene graft film) and a second region 107 made of an exposed surface 201 a of the substrate 201. In other words, the first region 106 and the second region 107 are formed so as to have different chemical properties. In this embodiment, the wettability of the component of the second segment A2 (see FIG. 6) of the polymer block copolymer, which will be described later, which is a material for forming the polymer thin film M (see FIG. 1), to the second region 107 is It is formed so as to be better than the first region 106.
The second region 107 corresponds to a “pattern portion” in the claims. The step of forming the first region 106 and the second region 107 on the surface of the substrate 201 corresponds to the “step of forming a pattern portion” referred to in the claims.

  This process is an example, and other means may be used as long as the chemically modified layer 401 provided on the surface of the substrate 201 can be patterned. Next, FIGS. 3A and 3B to be referred to are schematic views showing another aspect in which a chemically modified layer patterned on a substrate is arranged.

  As shown in FIG. 3A, the chemical modification layer 501 is patterned by being embedded in a plurality so as to be exposed on the surface of the substrate 201. In other words, the chemical modification layer 501 is discretely arranged so as to form regions having different chemical properties with respect to the exposed surface of the substrate 201, thereby forming the “pattern portion” as defined in the claims. Yes. Incidentally, as a method of forming the chemical modification layer 501, for example, a method of forming a concave portion of a predetermined pattern by applying a lithography method or the like to the substrate 201 and filling and arranging the chemical modification layer 501 in the concave portion. Can be adopted.

As shown in FIG. 3B, two types of chemically modified layers 501 and 502 having different chemical properties are arranged in a pattern on the surface of the substrate 201.
Incidentally, as a method of forming the chemically modified layers 501 and 502, for example, in the same manner as the method of forming the chemically modified layer 401 shown in FIGS. A method in which the chemical modification layer 502 is disposed between the chemically modified layers 501 so as to fill the exposed surface of the substrate 201 can be employed.

  Next, in the method for producing the polymer thin film M, the polymer block copolymer to be described later is microphase-separated on the substrate 201 having the patterned chemical modification layer 401 (polystyrene graft film). The inventive polymer thin film M (see FIG. 1) is obtained. Next, FIGS. 4A and 4B referred to are process explanatory views of a method for producing a polymer thin film according to an embodiment of the present invention.

  In this manufacturing method, as shown in FIG. 4A, a first region 106 composed of a patterned chemical modification layer 401 (polystyrene graft film) and a second region composed of an exposed surface 201a of the substrate 201 are used. A polymer block copolymer coating 202 described later is formed on a substrate 201 having the region 107. The coating film 202 corresponds to the “polymer layer” in the claims, and the step of forming the coating film 202 corresponds to the “first step” in the claims.

The coating film 202 is formed by preparing a dilute polymer block copolymer solution by dissolving the polymer block copolymer in a solvent, and applying this solution to the surface of the substrate 201 by a method such as spin coating or dip coating. What is necessary is just to apply | coat to. For example, when the spin coating method is used, the coating film 202 having a dry film thickness of about several tens of nm can be stably formed by setting the concentration of the solution to about several mass% and the rotation speed to 1000 to 5000 rotations per minute. Can get to.
The coating film 202 made of the polymer block copolymer has a structure in which the microphase separation of the polymer block copolymer does not proceed sufficiently due to the rapid vaporization of the solvent during the film formation, and the structure is non-equilibrium. In many cases, it is in a state of being completely or in a disordered state. Although the structure depends on the film forming method, it is usually not an equilibrium structure.

  Therefore, the coating film 202 is annealed in order to sufficiently advance the microphase separation process of the polymer block copolymer and obtain an equilibrium structure. As the annealing, for example, a thermal annealing method is applied in which the coating film 202 is heated to the glass transition temperature (Tg) or higher of the polymer block copolymer. In this embodiment using a polymer block copolymer described later, a thermal annealing method in which heating is performed at a temperature of 170 to 230 ° C. for several hours to several days in a vacuum atmosphere can be employed.

  And in this manufacturing method, as shown in FIG.4 (b), the 1st segment A1 of the polymer block copolymer mentioned later is carried out by carrying out micro phase separation of the coating film 202 (polymer layer) on the board | substrate 201. FIG. In the continuous phase 204 having the component (see FIG. 6), a plurality of columnar microdomains 203 having the second segment A2 (see FIG. 6) as a component are regularly arranged along the surface direction of the substrate 201. A fine structure arranged in the above is formed. This step corresponds to the “second step” in the claims.

  The wettability of the component of the second segment A2 (see FIG. 6) with respect to the second region 107 is better than the wettability of the component of the first segment A1 (see FIG. 6). And the wettability of the component of 1st segment A1 (refer FIG. 6) with respect to 1st area | region 106 becomes better than the wettability of the component of 2nd segment A2 (refer FIG. 6). In other words, the interfacial tension of the microdomain 203 with respect to the second region 107 is smaller than the interfacial tension with respect to the first region 106, and the interfacial tension of the continuous phase 204 with respect to the second region 107 is greater than the interfacial tension with respect to the first region 106. .

Then, as shown in FIG. 4B, the second segment is formed by the so-called chemical registration method in which the first region 106 and the second region 107 having different chemical properties are formed on the surface of the substrate 201 in this way. A columnar microdomain 203 composed of a component of A2 (see FIG. 6) is arranged on the second region 107 (exposed surface 201a of the substrate 201), and a continuous phase 204 composed of a component of the first segment A1 (see FIG. 6) is formed. It will be arranged on the first region 106 (the surface of the chemically modified layer 401).
In FIG. 4B, the micro domain 203 formed on the first region 106 is an interpolated (pattern interpolated) as will be described later.

Next, the chemical registration method used in this embodiment will be described in more detail.
In the chemical registration method, a long-range order of a microphase separation structure formed by self-organization of a polymer block copolymer is formed by a chemical resist provided on the surface of a substrate 201 as shown in FIG. This is a technique for improving the mark, that is, the second region 107 (pattern part: exposed surface 201a of the substrate 201) provided in the first region 106 (the surface of the chemically modified layer 401). According to this chemical registration method, defects in the second region 107 as chemical marks are interpolated (pattern interpolation) by self-organization of the polymer block copolymer.

  A typical example of a pattern in which the second region 107 as a chemical mark can be interpolated by applying the chemical registration method in the present embodiment is shown below. Next, FIG. 5A refers to the natural period do of the polymer block copolymer in this embodiment (hexagonal of FIG. 1) over the entire surface of the substrate over the second surface as a chemical mark. FIG. 5B is a conceptual diagram showing a state when the polymer block copolymer is microphase-separated and arranged so as to have a natural period do). FIG. 5B shows the defect rate of the second region as a chemical mark. FIG. 5 (c) is a conceptual diagram showing a state where the polymer block copolymer is microphase-separated and arranged so as to be 25%. FIG. 5C shows the defect rate of the second region as a chemical mark is 50%. FIG. 5D is a conceptual diagram showing a state in which the polymer block copolymer is microphase-separated, and the defect rate of the second region as a chemical mark is 75%. When the polymer block copolymer is microphase-separated It is a be conceptual diagram.

  As shown in FIG. 5A, when a substrate 201 in which the second regions 107 are arranged in a hexagonal manner (chemical mark defect rate 0%) is used, the polymer block copolymer in the present embodiment has a microphase. The microphase separation is performed so that the microdomain 203 is erected at a position corresponding to the second region 107 (hexagonal natural period do).

  Further, as shown in FIG. 5B, when the substrate 201 arranged so that the defect rate of the second region 107 as a chemical mark is 25% is used, the polymer block copolymer in the present embodiment is used. Is constrained by the microdomain 203 standing upright around the defect site in the second region 107 and microphase-separates so that the microdomain 203 stands upright at a position corresponding to the defect site in the second region 107. That is, the defect region in the second region 107 is interpolated by using the polymer block copolymer in the present embodiment, and chemical registration is realized with high accuracy.

  Further, as shown in FIG. 5C, the substrates 201 arranged so that the defect rate of the second region 107 as a chemical mark is 50% (pattern density 1/2), more specifically, every other row. When the substrate 201 on which the second region 107 is disposed is used, the polymer block copolymer in the present embodiment is constrained by the microdomain 203 that stands up around the defect site in the second region 107, and the second region 107. Microphase separation is performed so that the microdomains 203 stand upright at positions corresponding to the defect sites. That is, the defect region in the second region 107 is interpolated by using the polymer block copolymer in the present embodiment, and chemical registration is realized with high accuracy.

Further, as shown in FIG. 5D, the substrates 201 arranged so that the defect rate of the second region 107 as a chemical mark is 75% (pattern density ¼), more specifically, every other row. When the substrate 201 in which every other arranged second region 107 is arranged is used, the polymer block copolymer in this embodiment is restrained by the microdomain 203 standing upright around the defect site in the second region 107. Although the force is weak, microphase separation is performed so that the microdomain 203 is upright at a position corresponding to the defect site in the second region 107. That is, the defect region in the second region 107 is interpolated by using the polymer block copolymer in the present embodiment, and chemical registration is realized with high accuracy.
From the above, it is desirable that the arrangement period (lattice interval) of the second region 107 (pattern part) as a chemical mark on the surface of the substrate 201 is a natural number multiple of the natural period do of the microdomain.

(High molecular block copolymer)
As shown in FIG. 1, the polymer block copolymer used for forming the polymer thin film M of the present invention forms a continuous phase 204 and a microdomain 203 by microphase separation on a substrate 201. Next, FIG. 6 to be referred to is a conceptual diagram showing the state of the first segment and the second segment in the polymer block copolymer used for forming the polymer thin film of the present invention. It corresponds to a plan view.

  As shown in FIG. 6, the polymer block copolymer in the present embodiment includes a first segment A1 that is a component that forms the continuous phase 204 and a second segment A2 that is a component that forms the microdomain 203. Have.

In such a polymer block copolymer, it is desirable that the volume of the second segment A2 occupied on the substrate 201 (see FIG. 1) is smaller than the volume of the first segment A1.
The volume of the first segment A1 and the second segment A2 can be adjusted by changing the degree of polymerization of the polymer chains constituting them.

Incidentally, the boundary between the continuous phase 204 and the microdomain 203 is determined in the vicinity of the joint between the first segment A1 and the second segment A2. Accordingly, the polymer block copolymer preferably has a narrow molecular weight distribution, and more preferably a polymer block copolymer synthesized by the living anion polymerization method. In addition to those synthesized by the living anion polymerization method described above, those synthesized by an atom transfer radical polymerization method, a reversible addition-fragmentation chain transfer polymerization method, a nitroxide-mediated polymerization method, a ring-opening metathesis polymerization method, etc. should be used. Can do.
Moreover, as a polymer block copolymer in this embodiment, what has a polymer chain shown by following Structural formula (1) is mentioned, for example.

In the structural formula (1), M is a hydrogen atom or a monovalent organic group which may be the same or different, and L is a — (CH ₂ ) _n — group (where n is 5 ≦ n ≦ 24, preferably an integer of 5 to 15, and a molecular length of about 1 to 5 nm is desirable. In the structural formula (1), POSS is a polyhedral oligomeric silsesquioxane (silsesquioxane skeleton), p is an integer of 1 to 1000, and r is an integer of 1 to 70. .

Incidentally, the polymer block copolymer used in the present invention is not limited to the polymer block copolymer represented by the structural formula (1), but the first segment A1 (see FIG. 6) or the second segment. The segment A2 (see FIG. 6) has a silsesquioxane skeleton, and this silsesquioxane skeleton is represented by the aforementioned — (CH ₂ ) _n — group with respect to the main chain of the polymer block copolymer. What is necessary is just to be couple | bonded through the organic group containing the alkyl chain to be. Therefore, the main chain constituting the first segment A1 (see FIG. 6) and the second segment A2 (see FIG. 6) is the same as the main chain of a known polymer block copolymer used for microphase separation. Among them, a polymer block copolymer represented by the following structural formula (2) is preferable.

However, in the above structural formula (2), R ¹ may hydrogen atom optionally the same as or different from each other, alkyl having 1 to 24 carbon atoms, or an aryl. R ² is an alkyl moiety derived from a reaction initiator used in the living anion polymerization method, and among them, sec-butyl is desirable.
In the structural formula (2), examples of D include a divalent 1,1-diphenylethylene group and derivatives thereof. X is a divalent organic group constituting the linker, and will be described in detail later.
In the structural formula (2), n, p and r have the same meanings as n, p and r in the structural formula (1).

  The polyhedral oligomeric silsesquioxane (POSS) is preferably represented by the following structural formula. In the following structural formula of POSS, R is a functional group selected from methyl, ethyl, isobutyl, cyclopentyl, cyclohexyl, phenyl, and isooctyl, and may be the same or different from each other.

Examples of the divalent organic group represented by X in the structural formula (2) include those represented by the following structural formula.
In the following divalent organic groups, the molecular chain terminal located on the right side of the paper is represented as the main chain side of the polymer block copolymer, and the molecular chain terminal located on the left side of the paper is represented as the POSS side.
Moreover, the notation of “cis / trans” in the following structural formula indicates that it includes a cis-trans isomer in a carbon-carbon double bond in the structural formula.

In addition, the alkyl chain represented by the aforementioned — (CH ₂ ) _n — group and POSS may be directly bonded.

  In the polymer block copolymer (POSS-containing block copolymer) represented by the above structural formulas (1) and (2), the POSS-containing block is the first segment A1 (see FIG. 6). The block not containing POSS corresponds to the second segment A2 (see FIG. 6).

And as above-mentioned, the polymer block copolymer in this embodiment is in the side chain in any one block of 1st segment A1 (refer FIG. 6) and 2nd segment A2 (refer FIG. 6), - (CH ₂₎ n _- group (where, n is an integer of 5 ≦ n ≦ 24) as long as it contains a silsesquioxane skeleton bonded through a divalent organic group containing a.

  More preferable examples of such a polymer block copolymer include those represented by the following structural formula (3).

  However, in the structural formula (3), R is isobutyl, Me is methyl, Ph is phenyl, sec-Bu is secondary butyl, and X, n, p, and r are the structural formulas ( It is synonymous with X, n, p, r of 2).

  The polymer block copolymer according to this embodiment as described above is obtained by lengthening a group interposed between the first segment A1 or the second segment A2 (see FIG. 6) and the silsesquioxane skeleton. It is considered that the degree of freedom of positional displacement (fluctuation) of an organic group having a silsesquioxane skeleton as a side chain at the time of thermal annealing is improved and a microphase separation structure can be expressed.

  In addition, as described above, the polymer block copolymer according to the present embodiment is an AB type formed by bonding the ends of the first segment A1 (see FIG. 6) and the second segment (see FIG. 6). Although the polymer diblock copolymer was illustrated, the polymer block copolymer used in the present invention includes an ABA polymer triblock copolymer and an ABC polymer comprising three or more polymer segments. It may be a linear polymer block copolymer such as a block copolymer or a star-type polymer block copolymer.

(Microstructure and manufacturing method thereof)
Next, a fine structure obtained using the polymer thin film M will be described. FIGS. 7A to 7F referred to here are process diagrams for explaining a manufacturing method of a fine structure obtained by using the polymer thin film in the present embodiment. 7A to 7F, the description of the surface of the patterned substrate 201 is omitted. In the following description, the fine structure refers to a surface on which an uneven surface corresponding to a regular arrangement pattern of a microphase separation structure is formed.

  In this manufacturing method, as shown in FIG. 7A, a polymer thin film M having a microphase separation structure composed of a continuous phase 204 and a columnar microdomain 203 is prepared. Reference numeral 201 denotes a substrate.

Next, in this manufacturing method, as shown in FIG. 7B, by removing the microdomain 203 (see FIG. 7A), the substrate 201 and the plurality of micro holes H are regularly arranged. The microstructure 21 provided with the porous thin film D thus obtained is obtained.
Note that here, any one of the continuous phase 204 and the microdomain 203 may be removed, and although not shown, the microstructure 21 has a plurality of columnar shapes by removing the continuous phase 204 from the microphase separation structure. The body may be regularly arranged.

  As a method for removing either the continuous phase 204 of the polymer thin film M or the microdomain 203 of the columnar body, an etching rate between the continuous phase 204 and the microdomain 203 by reactive ion etching (RIE) or other etching methods is used. A method using the difference between the two is mentioned.

In addition, it is possible to improve etching selectivity by doping one of the continuous phase 204 and the microdomain 203 with a metal atom or the like.
In addition, after removing either one of the continuous phase 204 and the micro domain 203, the fine structure 21 is formed by etching the substrate 201 using either the remaining continuous phase 204 or the micro domain 203 as a mask. It may be obtained.

  That is, like the continuous phase 204 shown in FIG. 7B, the substrate 201 is etched by RIE or plasma etching using the remaining polymer phase (porous thin film D) as a mask. As a result, as shown in FIG. 7C, the surface portion of the substrate 201 corresponding to the portion of the polymer phase (porous thin film D) removed through the fine holes H is processed, and the micro separation structure is formed. The pattern is transferred to the surface of the substrate 201. Then, when the porous thin film D remaining on the surface of the fine structure 21 is removed by RIE or a solvent, as shown in FIG. 7D, it corresponds to the micro domain 203 of the columnar body (see FIG. 7A). Thus, the fine structure 21a having the fine holes H having the pattern formed on the surface is obtained.

Further, the fine structure 21 may be copied by transferring the pattern arrangement using the fine structure 21 as a master.
That is, the other polymer phase (porous thin film D) remaining like the continuous phase 204 shown in FIG. 7B is brought into close contact with the transfer target 30 as shown in FIG. The phase separation structure pattern is transferred to the surface of the transfer target 30. Thereafter, as shown in FIG. 7F, the pattern of the porous thin film D (see FIG. 7E) is formed by peeling the transfer target 30 from the fine structure 21 (see FIG. 7E). A transferred replica (fine structure 21b) can be obtained.

  Here, the material of the transfer target 30 may be selected according to the use, such as nickel, platinum, gold or the like if it is a metal, or glass or titania if it is an inorganic material. When the transfer target 30 is made of metal, the transfer target 30 can be brought into close contact with the uneven surface of the fine structure 21 (see FIG. 7E) by sputtering, vapor deposition, plating, or a combination thereof. is there.

  Further, when the transfer target 30 is an inorganic substance, it can be adhered by using, for example, a sol-gel method in addition to sputtering or CVD. Here, the plating method and the sol-gel method are desirable because they can accurately transfer a regular array pattern of several tens of nanometers in a microphase-separated structure and can be expected to reduce the cost by a non-vacuum process. is there.

The microstructures 21, 21a, and 21b (see FIGS. 7B, 7D, and 7F) obtained by the manufacturing method described above have a finely concavo-convex surface of a pattern formed on the surface and an aspect ratio. Since the ratio is large, it is applied to various uses.
For example, the surfaces of the manufactured microstructures 21, 21a, 21b are repeatedly brought into close contact with the transfer target by a nanoimprint method or the like, so that the microstructures 21, 21a, 21b having the same regular arrangement pattern on the surface are used. It can be used for the purpose of manufacturing a large number of replicas.

Hereinafter, a method for transferring the fine pattern on the uneven surface of the fine structures 21, 21a, 21b (see FIGS. 7B, 7D, and 7F) to the transferred object 30 by the nanoimprint method will be described.
The first method is a method of imprinting the manufactured microstructures 21, 21a, 21b directly onto the transfer target 30 to transfer a regular array pattern (this method is called a thermal imprint method). . This method is suitable when the transfer target 30 is made of a material that can be directly imprinted. For example, when a thermoplastic resin typified by polystyrene is used as the transfer target 30, the microstructures 21, 21a, and 21b are pressed against the transfer target 30 after the thermoplastic resin is heated to the glass transition temperature or higher. When the microstructures 21, 21 a, 21 b are released from the surface of the transfer target 30 after being brought into close contact and cooled to a glass transition temperature or lower, a replica can be obtained.

  As a second method, when the microstructures 21, 21a, and 21b (see FIGS. 7B, 7D, and 7F) are made of a light-transmitting material such as glass, photocuring property is obtained. Resin is applied as an object to be transferred (not shown) (this method is called an optical imprint method). When this photo-curable resin is adhered to the fine structures 21, 21a, 21b and irradiated with light, the photo-curable resin is cured, so that the fine structures 21, 21a, 21b are released and cured. The photo-curable resin (transfer object) can be used as a replica.

  Further, in such an optical imprinting method, for example, when a glass substrate is used as a transfer target (not shown), the photo-curing property is formed in the gap between the microstructures 21, 21a, and 21b and the glass substrate. The resin is in close contact with each other and irradiated with light. Then, after curing the photocurable resin, the microstructures 21, 21a and 21b are released, and the cured photocurable resin having irregularities on the surface is used as a mask, and a glass substrate is formed by plasma or ion beam. There is also a transfer method in which the regular array pattern is etched.

  According to the above-described polymer thin film having a silsesquioxane, a fine structure, and a manufacturing method thereof according to the present embodiment as described above, the structure is further miniaturized as compared with the prior art, and the rule is widely applied. It is possible to obtain a fine structure having a structure with excellent properties and few defects.

  The microstructure of the present invention exemplified by the polymer thin film M, the microstructures 21, 21a, 21b, and replicas thereof can be applied to information recording media such as magnetic recording media and optical recording media. . In addition, such a microstructure of the present invention includes large-scale integrated circuit components, optical components such as lenses, polarizing plates, wavelength filters, light-emitting elements, and optical integrated circuits, bioanalyses such as immunoassay, DNA separation, and cell culture. It can be applied to devices.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It can implement with a various other form.
In the above-described embodiment, the polymer thin film M in which the microdomain 203 has a columnar shape has been described as shown in FIG. 1, but in the present invention, the shape of the microdomain 203 may be spherical or lamellar (layered).

  In such a polymer thin film M, the volume ratio of the component of the first segment A1 (see FIG. 6) and the component of the second segment A2 (see FIG. 6) on the substrate 201 when microphase separation is performed. The shape of the microdomain 203 can be changed by adjusting the degree of polymerization of the polymer block copolymer so as to adjust. More specifically, as the ratio of the component of the second segment A2 (see FIG. 6) to the total volume increases from 0% to 50%, the microdomain composed of the component of the second segment A2 (see FIG. 6). The shape of 203 changes from a regularly arranged spherical shape to a lamellar shape through a columnar shape.

Next, FIG. 8 referred to is a perspective view schematically showing a state in which the polymer block copolymer forms a lamellar microphase separation structure by microphase separation.
As shown in FIG. 8, the lamellar microphase separation structure on the substrate 201 has a lamellar microdomain 203 composed of a component of the second segment A2 (see FIG. 6), and the first segment A1 (see FIG. 6). It becomes a structure arrange | positioned at equal intervals in the continuous phase 204 which consists of these components.
In FIG. 8, the symbol do indicates the natural period of the polymer block copolymer, and although not shown, the patterning of the polystyrene graft film provided on the substrate 201 corresponds to the microdomain 203 and the continuous phase 204. In this way, the stripes are formed at equal intervals.

Next, the present invention will be described more specifically with reference to examples.
Example 1
In Example 1, a polymer block copolymer for forming a polymer thin film was first prepared. Specifically, it is a polymer block copolymer represented by the following structural formula (4).

However, R in Structural Formula (4) is isobutyl, and Ph and sec-Bu have the same meanings as Ph and sec-Bu in Structural Formula (3).
This polymer block copolymer is a poly (CH ₂ ) ₁₁ — group (n = 11 in the above structural formula (2)), a divalent organic group, and a side chain comprising a silsesquioxane skeleton. It is a diblock copolymer obtained by combining methacrylate (hereinafter sometimes referred to as PMAC11POSS) and polymethyl methacrylate (PMMA), which is known as a general hydrocarbon polymer. The number average molecular weight Mn of this polymer block copolymer is 30,700.

Moreover, this polymer block copolymer had a polydispersity index Mw / Mn of the molecular weight distribution as a whole of 1.07. This polymer block copolymer undergoes microphase separation into a columnar microdomain made of PMMA and a continuous phase made of PMAC11POSS.
Hereinafter, the polymer block copolymer in Example 1 may be referred to as “first polymer block copolymer” and may be referred to as “PMMA-b-PMAC11POSS (1)”.

<Measurement of glass transition temperature (Tg)>
The glass transition temperature (Tg) of the first polymer block copolymer was measured using differential scanning calorimetry. As a result, an endothermic peak of about 100 ° C. was detected, and it was confirmed that the first polymer block copolymer had a clear glass transition temperature (Tg).

<Measurement of natural period do of first polymer block copolymer>
In measuring the natural period do (see FIG. 1) of the first polymer block copolymer, first, the polymer block copolymer was dissolved in chloroform to obtain a polymer block having a concentration of 1.0% by mass. A chloroform solution of the copolymer was obtained. Next, the solvent was gradually removed to obtain a bulk sample of the polymer block copolymer. The bulk sample was subjected to structural analysis by a small angle X-ray scattering (SAXS) method.

  FIG. 9 is an X-ray small angle scattering (SAXS) curve of the first polymer block copolymer (PMMA-b-PMAPOSS (1)) microphase-separated. As a result, it was found from the scattering profile that there are at least three maximums (arrows 1, 2, and 3 in FIG. 9), and the relative peak positions are 1: √3: √4. That is, it was confirmed that these polymer block copolymers were microphase-separated into a columnar microdomain made of PMMA and a continuous phase made of PMAC11POSS. Furthermore, it was confirmed from the local maximum position that the natural period do was 25 nm (actual measurement value was 24.8 nm). The results are shown in Table 1.

<Formation of polystyrene graft film>
Next, in Example 1, a substrate for forming a thin film made of the first polymer block copolymer was prepared. A Si wafer (4 inches (10.2 cm)) having a natural oxide film was used as the substrate.
Next, the Si wafer as the substrate was washed with a piranha solution. By this piranha treatment, organic substances on the surface of the Si wafer were removed and the surface was oxidized to increase the surface hydroxyl group density.
Next, a toluene solution (PS-OH concentration 2.0%) of polystyrene (hereinafter referred to as PS-OH) terminated with a hydroxyl group is prepared, and this is applied to the surface of a Si wafer on a spin coater (Mikasa Co., Ltd.). 1H-360S, rotation speed 2000 rpm).
The molecular weight of PS-OH was 3,700. The film thickness of the obtained PS-OH was about 50 nm.

  Next, the substrate coated with PS-OH was put into a vacuum oven and heated at 140 ° C. for 72 hours. By this treatment, the hydroxyl group at the end of PS-OH and the hydroxyl group on the substrate surface were chemically bonded by dehydration reaction. Finally, the substrate was immersed in toluene and subjected to ultrasonic treatment to remove unreacted PS-OH to obtain a substrate having a polystyrene graft layer.

  In order to evaluate the surface state of the substrate on which the polystyrene graft layer was formed, the thickness of the polystyrene graft layer, the amount of carbon on the surface, and the contact angle of homopolystyrene (hereinafter abbreviated as hPS) to the surface were measured. A spectroscopic ellipsometry method was employed for measuring the thickness of the polystyrene graft layer, and an X-ray photoelectron spectroscopy (XPS method) was employed for measuring the carbon amount.

The thickness of the polystyrene graft layer was 5.1 nm.
The amount of carbon on the substrate surface on which the polystyrene graft layer was formed was determined as the integrated intensity of the peak derived from the C1S. The integrated intensities were 4,500 cps and 27,000 cps.

  The contact angle of hPS with respect to the polystyrene graft layer on the substrate surface was 9 degrees. The contact angle of hPS with respect to the surface of the substrate made of Si wafer was 35 degrees. That is, it was confirmed that a polystyrene graft film could be formed on the substrate surface from the decrease in the contact angle.

Incidentally, the measurement of the contact angle of hPS with the substrate surface was carried out by the following method.
First, hPS having a number average molecular weight of 4000 was spin-coated on the substrate surface so as to be a thin film having a thickness of about 80 nm. Next, the substrate on which hPS was formed was annealed at a temperature of 170 ° C. for 24 hours in a vacuum atmosphere. By this treatment, the hPS thin film was dewetted on the substrate surface to form fine droplets. After this heat treatment, the substrate was taken out of the heating furnace and immersed in liquid nitrogen to be rapidly cooled to freeze the droplet shape.
The cross-sectional shape of the obtained droplet was measured with an atomic force microscope, and the contact angle of hPS with respect to the substrate at the temperature during the heat treatment was determined by measuring the angle of the interface between the substrate and the droplet. At this time, the angle was measured for 6 points, and the average value was taken as the contact angle.

<Patterning of polystyrene graft film (chemically modified layer)>
Next, FIG. 10 (a) to be referred to is a plan view showing a partially enlarged polystyrene graft film, and FIG. 10 (b) is a pattern lattice on the surface of the patterned polystyrene graft film. FIG. 10C is a plan view schematically showing the arrangement of regions having different intervals d, and FIG. 10C is a plan view of a diced substrate.

  First, as shown in FIG. 10C, a substrate 201 (Si wafer) on which a polystyrene graft film (chemically modified layer 401) was formed was diced into a size of 2 cm square.

Next, the polystyrene graft film of the diced substrate 201 was patterned (patterned) by EB lithography.
In this patterning (patterning), as shown in FIG. 10A, a chemically modified layer 401 made of a polystyrene graft film as the first region 106 and a chemically modified layer 401 (polystyrene graft film) on the substrate 201 are formed. ) Are partially removed to form the second region 107 constituted by the exposed surface 201 a of the substrate 201. The second region 107 is formed of a plurality of circular shapes having a diameter r arranged in a hexagonal manner with a lattice interval d.

This patterning (patterning) will be described in more detail.
In this patterning (patterning), as shown in FIG. 10B, the surface of the chemically modified layer 401 (polystyrene graft film) is partitioned by 100 μm square, and the measured natural period of the polymer block copolymer is measured. The region (d = 25 nm) where the lattice spacing d is set so that the ratio (d / do) of the lattice spacing d to do (25 nm) is “1”, and the ratio (d / do) is “2”. And a region where the lattice spacing d is set (a region where d = 50 nm).
In FIG. 10B, the region of d = 18 nm and the region of d = 36 nm, the region of d = 28 nm, and the region of d = 56 nm will be described in Example 2 and Example 3 described later.

  Incidentally, the circular diameter r of the sectioned area is about 25% to 30% of each lattice spacing d, but may be 25% or less or 30% or more. There is no particular limitation as long as the arrangement of the separation structure can be controlled.

Next, the patterning method in Example 1 will be described more specifically with reference to FIGS. 2 (a) to 2 (f).
In this patterning method, a resist film 402 made of polymethyl methacrylate shown in FIG. 2B is formed on the surface of the chemically modified layer 401 made of polystyrene graft film shown in FIG. 2A by spin coating. It formed so that it might become 50 nm.

  Next, as shown in FIG. 2C, the resist film 402 was exposed with an EB drawing apparatus at an acceleration voltage of 100 kV so as to correspond to the patterning described above. Here, the circular diameter r (see FIG. 10A) of patterning was adjusted by the exposure amount of EB at each lattice point. Thereafter, as shown in FIG. 2D, the resist film 402 was developed to obtain a patterned resist film 402.

Next, as shown in FIG. 2E, the chemically modified layer 401 was removed by RIE using oxygen gas using the patterned resist film 402 as a mask. RIE was performed using an ICP dry etching apparatus. At this time, the output of the apparatus was set to 100 W, the oxygen gas pressure was set to 1 Pa, the oxygen gas flow rate was set to 10 cm ³ / min, and the treatment time was set to 5 to 20 seconds. As a result, the first region 106 made of the chemically modified layer 401 (polystyrene graft film) and the second region 107 made of the exposed surface 201a of the substrate 201 were formed.

  Then, as shown in FIG. 2 (f), the resist film 402 (see FIG. 2 (e)) remaining on the surface of the substrate 201 is removed with toluene, so that a chemically modified layer 401 patterned on the surface is formed. A substrate 201 was obtained.

<Formation of polymer thin film using chemical registration method>
Here, as shown to Fig.4 (a), the 2nd area | region which consists of the 1st area | region 106 which consists of the chemically modified layer 401 (polystyrene graft film) patterned, and the exposed surface 201a of the board | substrate 201 (Si wafer). The coating film 202 of the polymer block copolymer was formed on the substrate 201 having 107.
And the polymer thin film M (refer FIG. 1) of this invention was obtained by carrying out the micro phase separation of the coating film 202 of a polymer block copolymer.
This microphase separation process was performed by performing thermal annealing at 180 ° C. for 24 hours.

Next, the structure of the microphase separation of the polymer thin film M was observed with a scanning electron microscope (SEM manufactured by Hitachi, Ltd., model S4800). SEM observation was performed under the condition of an acceleration voltage of 1.5 kV.
As a sample for SEM observation, a columnar microdomain made of PMMA present in the polymer thin film M was decomposed and removed by the RIE method. As the RIE apparatus, RIE-10NP manufactured by Samco Corporation was used, and the etching was performed under the conditions of an oxygen gas pressure of 1.0 Pa, a gas flow rate of 10 cm ³ / min, a power of 20 W, and an etching time of 30 seconds.
In order to accurately measure the fine structure, the necessary contrast was obtained by adjusting the acceleration voltage without performing deposition of Pt or the like on the surface of the sample, which is usually performed for the prevention of charging in SEM observation.

  As a result of SEM observation, it was confirmed that nanoscale fine holes (column-shaped microdomain decomposition and removal portions) derived from the structure of microphase separation were arranged hexagonally in the sample. That is, in the polymer thin film M, as shown in FIG. 4B, columnar microdomains 203 made of PMMA segments (second segment A2 shown in FIG. 6) are constrained by the second region 107 and arranged. At the same time, the continuous phase 204 composed of the PMAC11POSS segment (the first segment A1 shown in FIG. 6) is formed on the first region 106 formed by the patterned chemical modification layer 401 (polystyrene graft film). Was confirmed.

The ratio (d / do) to the natural period do (25 nm) of the polymer block copolymer is “1” (d = 25 nm) and “2” (d = 50 nm). The columnar microdomains 203 are oriented perpendicularly to the substrate 201 and are periodically arranged in the surface direction of the substrate 201 over a long distance.
Since the microdomains 203 in the present example are almost not deficient and are regularly arranged over a long distance, the evaluation results are shown as “◯” in Table 1.

(Example 2)
In Example 2, a polymer block copolymer having the number average molecular weight Mn of 23700 represented by the structural formula (4) was prepared as a polymer block copolymer for forming a polymer thin film.
This polymer block copolymer, like the polymer block copolymer in Example 1, is a — (CH ₂ ) ₁₁ — group (n = 11 in the structural formula (2)), a divalent organic compound. It is a diblock copolymer in which polymethacrylate (PMAC11POSS) having a side chain composed of a group and a silsesquioxane skeleton is combined with polymethylmethacrylate (PMMA).

Further, this polymer block copolymer had a polydispersity index Mw / Mn of the molecular weight distribution as a whole of 1.04. This polymer block copolymer undergoes microphase separation into a columnar microdomain made of PMMA and a continuous phase made of PMAC11POSS.
Hereinafter, the polymer block copolymer in Example 2 may be referred to as a “second polymer block copolymer” and may be referred to as “PMMA-b-PMAC11POSS (2)”.

  Next, the glass transition temperature (Tg) of the second polymer block copolymer was measured using differential scanning calorimetry. As a result, an endothermic peak of about 100 ° C. was detected, and it was confirmed that the second polymer block copolymer had a clear glass transition temperature (Tg).

  Further, as a result of measuring the natural period do of this second polymer block copolymer in the same manner as in Example 1, it was confirmed that the natural period do was 18 nm (actual measurement value was 17.9 nm). .

Next, in Example 2, as in Example 1, as shown in FIG. 2A, a chemically modified layer 401 (polystyrene graft film) is formed on the substrate 201, and this chemically modified layer is formed. 401 patterning was performed.
That is, as shown in FIG. 10A, the chemically modified layer 401 made of a polystyrene graft film as the first region 106 and the second region 107 constituted by the exposed surface 201a of the substrate 201 were formed.
More specifically, on the surface of the chemically modified layer 401 (polystyrene graft film) formed on the substrate 201, the lattice spacing d shown in FIG. 10 (a) with respect to the measured natural block do (18 nm) of the polymer block copolymer. The area (d = 18 nm shown in FIG. 10B) in which the lattice spacing d is set so that the ratio (d / do) of “1” is “1”, and the ratio (d / do) is “2”. A region where the lattice spacing d was set (region where d = 36 nm shown in FIG. 10B) was formed.

Next, in Example 2, using the second polymer block copolymer, as shown in FIG. 4 (a), a first layer consisting of a chemically modified layer 401 (polystyrene graft film) patterned. A coating film 202 of a polymer block copolymer was formed on the substrate 201 having the region 106 and the second region 107 composed of the exposed surface 201a of the substrate 201 (Si wafer).
And the polymer thin film M (refer FIG. 1) of this invention was obtained by carrying out micro phase separation of this coating film 202. FIG.
This microphase separation process was performed by performing thermal annealing at 180 ° C. for 24 hours.

  As a result, in the polymer thin film M, as shown in FIG. 4B, columnar microdomains 203 composed of PMMA segments (second segment A2 shown in FIG. 6) are constrained by the second region 107 and arranged. At the same time, the continuous phase 204 composed of the PMAC11POSS segment (the first segment A1 shown in FIG. 6) is formed on the first region 106 formed by the patterned chemical modification layer 401 (polystyrene graft film). It was confirmed.

The ratio (d / do) to the natural period do (18 nm) of the polymer block copolymer is “1” (d = 18 nm) and “2” (d = 36 nm). The columnar microdomains 203 are oriented perpendicularly to the substrate 201 and are periodically arranged in the surface direction of the substrate 201 over a long distance.
Since the microdomains 203 in the present example are almost not deficient and are regularly arranged over a long distance, the evaluation results are shown as “◯” in Table 1.

(Example 3)
In Example 3, a polymer block copolymer having a number average molecular weight Mn of 35800 represented by the structural formula (4) was prepared as a polymer block copolymer for forming a polymer thin film.
This polymer block copolymer is a poly (CH ₂ ) ₅ — group (n = 5 in the structural formula (2)), a divalent organic group, and a side chain comprising a silsesquioxane skeleton. A diblock copolymer obtained by combining methacrylate (hereinafter sometimes referred to as PMAC5POSS) and polymethyl methacrylate (PMMA).

Moreover, this polymer block copolymer had a polydispersity index Mw / Mn of the molecular weight distribution as a whole of 1.05. This polymer block copolymer undergoes microphase separation into a columnar microdomain made of PMMA and a continuous phase made of PMAC5POSS.
Hereinafter, the polymer block copolymer in Example 2 may be referred to as “third polymer block copolymer” and may be referred to as “PMMA-b-PMAC5POSS”.

  Next, the glass transition temperature (Tg) of the third polymer block copolymer was measured using differential scanning calorimetry. As a result, an endothermic peak of about 100 ° C. was detected, and it was confirmed that the third polymer block copolymer had a clear glass transition temperature (Tg).

  Further, as a result of measuring the natural period do of this third polymer block copolymer in the same manner as in Example 1, it was confirmed that the natural period do was 28 nm (actual measurement value was 27.6 nm). .

Next, in Example 3, a polystyrene graft film (chemically modified layer) was formed on the substrate 201 in the same manner as in Example 1, and the polystyrene graft film (chemically modified layer) was patterned.
That is, as shown in FIG. 10A, the second region constituted by the chemically modified layer 401 made of a polystyrene graft film as the first region 106 (see FIG. 2F) and the exposed surface 201 a of the substrate 201. Region 107 was formed.

  More specifically, on the surface of the chemically modified layer 401 (polystyrene graft film) formed on the substrate 201, the lattice spacing shown in FIG. 10 (a) with respect to the measured natural period do (28 nm) of the polymer block copolymer. The region (d = 28 nm shown in FIG. 10B) where the lattice spacing d is set so that the ratio d (d / do) is “1”, and the ratio (d / do) is “2”. A region where the lattice interval d is set (region where d = 56 nm shown in FIG. 10B) is formed.

Next, in Example 3, using the third polymer block copolymer, as shown in FIG. 4 (a), a first layer composed of a chemically modified layer 401 (polystyrene graft film) patterned. A coating film 202 of a polymer block copolymer was formed on the substrate 201 having the region 106 and the second region 107 composed of the exposed surface 201a of the substrate 201 (Si wafer).
And the polymer thin film M (refer FIG. 1) of this invention was obtained by carrying out micro phase separation of this coating film 202. FIG.
This microphase separation process was performed by performing thermal annealing at 180 ° C. for 24 hours.

  As a result, in the polymer thin film M, as shown in FIG. 4B, columnar microdomains 203 composed of PMMA segments (second segment A2 shown in FIG. 6) are constrained by the second region 107 and arranged. At the same time, the continuous phase 204 composed of the PMAC5POSS segment (the first segment A1 shown in FIG. 6) is formed on the first region 106 formed by the patterned chemical modification layer 401 (polystyrene graft film). It was confirmed.

The ratio (d / do) to the natural period do (28 nm) of the polymer block copolymer is “1” (d = 28 nm) and “2” (d = 56 nm). The columnar microdomains 203 are oriented perpendicularly to the substrate 201 and are periodically arranged in the surface direction of the substrate 201 over a long distance.
Since the microdomains 203 in the present example are almost not deficient and are regularly arranged over a long distance, the evaluation results are shown as “◯” in Table 1.

(Example 4)
In Example 4, a polymer block copolymer having a number average molecular weight Mn of 34700 represented by the structural formula (4) was prepared as a polymer block copolymer for forming a polymer thin film.
This polymer block copolymer is a poly (CH ₂ ) ₁₅ — group (n = 15 in the structural formula (2)), a divalent organic group, and a side chain comprising a silsesquioxane skeleton. A diblock copolymer obtained by combining methacrylate (hereinafter sometimes referred to as PMAC15POSS) and polymethyl methacrylate (PMMA).

Moreover, this polymer block copolymer had a polydispersity index Mw / Mn of the molecular weight distribution as a whole of 1.05. This polymer block copolymer undergoes microphase separation into a columnar microdomain made of PMMA and a continuous phase made of PMAC15POSS.
Hereinafter, the polymer block copolymer in Example 2 may be referred to as a “fourth polymer block copolymer” and may be referred to as “PMMA-b-PMAC15POSS”.

  Next, the glass transition temperature (Tg) of the fourth polymer block copolymer was measured using differential scanning calorimetry. As a result, an endothermic peak of about 100 ° C. was detected, and it was confirmed that the second polymer block copolymer had a clear glass transition temperature (Tg).

  Further, as a result of measuring the natural period do of this fourth polymer block copolymer in the same manner as in Example 1, it was confirmed that the natural period do was 28 nm (actual measurement value was 28.1 nm). .

  Next, in Example 4, a polystyrene graft film (chemically modified layer) was formed on the substrate 201 in the same manner as in Example 1, and the polystyrene graft film (chemically modified layer) was patterned.

  That is, as shown in FIG. 10A, the chemical modification layer 401 made of a polystyrene graft film as the first region 106 and the chemical modification layer 401 (polystyrene graft film) on the substrate 201 are partially removed. Thus, the second region 107 constituted by the surface 201a from which the substrate 201 was exposed was formed.

  More specifically, in the same manner as in Example 3, the surface of the chemically modified layer 401 (polystyrene graft film) formed on the substrate 201 has a measured characteristic block do (28 nm) of the polymer block copolymer as shown in FIG. The region (d = 28 nm region shown in FIG. 10B) in which the lattice interval d is set so that the ratio (d / do) of the lattice interval d shown in a) is “1”, and the ratio (d / A region (the region of d = 56 nm shown in FIG. 10B) in which the lattice spacing d is set so that do) becomes “2” was formed.

Next, in Example 4, as shown in FIG. 4 (a), a first polymer block copolymer (polystyrene graft film) made of a fourth polymer block copolymer is used. A coating film 202 of a polymer block copolymer was formed on the substrate 201 having the region 106 and the second region 107 composed of the exposed surface 201a of the substrate 201 (Si wafer).
And the polymer thin film M (refer FIG. 1) of this invention was obtained by carrying out micro phase separation of this coating film 202. FIG.
This microphase separation process was performed by performing thermal annealing at 180 ° C. for 24 hours.

  As a result, in the polymer thin film M, as shown in FIG. 4B, columnar microdomains 203 composed of PMMA segments (second segment A2 shown in FIG. 6) are constrained by the second region 107 and arranged. At the same time, the continuous phase 204 composed of the PMAC15POSS segment (the first segment A1 shown in FIG. 6) is formed on the first region 106 formed by the patterned chemical modification layer 401 (polystyrene graft film). It was confirmed.

The ratio (d / do) to the natural period do (28 nm) of the polymer block copolymer is “1” (d = 28 nm) and “2” (d = 56 nm). The columnar microdomains 203 are oriented perpendicularly to the substrate 201 and are periodically arranged in the surface direction of the substrate 201 over a long distance.
Since the microdomains 203 in the present example are almost not deficient and are regularly arranged over a long distance, the evaluation results are shown as “◯” in Table 1.

(Comparative Example 1)
In Comparative Example 1, a polymer block copolymer having a number average molecular weight Mn of 31000 represented by the structural formula (5) was prepared as a polymer block copolymer for forming a polymer thin film.

However, R in Structural Formula (5) is isobutyl, and Ph and sec-Bu are synonymous with Ph and sec-Bu in Structural Formula (4).
This polymer block copolymer is a polymethacrylate (hereinafter referred to as PMAPOSS) having a — (CH ₂ ) — group (n = 3 in the structural formula (2)) and a side chain comprising a silsesquioxane skeleton. A diblock copolymer obtained by combining polymethylmethacrylate (PMMA).
Moreover, this polymer block copolymer had a polydispersity index Mw / Mn of the molecular weight distribution as a whole of 1.05.
Hereinafter, the polymer block copolymer in Comparative Example 1 may be referred to as “fifth polymer block copolymer” and may be referred to as “PMMA-b-PMAPOSS”.

  Next, an attempt was made to measure the glass transition temperature (Tg) of the fifth polymer block copolymer by using differential scanning calorimetry, but no endothermic peak was detected, and the fifth polymer block copolymer was measured. It was confirmed that the coalescence did not have a clear glass transition temperature (Tg).

  Further, as a result of measuring the natural period do of this fifth polymer block copolymer in the same manner as in Example 1, it was confirmed that the natural period do was 25 nm (actual measurement value was 24.7 nm). .

Next, in Comparative Example 1, a polystyrene graft film (chemically modified layer) was formed on the substrate 201 in the same manner as in Example 1, and this polystyrene graft film (chemically modified layer) was patterned.
That is, although not shown, the ratio of the lattice spacing d to the measured natural period do (25 nm) of the polymer block copolymer (d) on the surface of the chemically modified layer 401 (polystyrene graft film) formed on the substrate 201 (d / Do) is a region where the lattice spacing d is set to be “1” (a region where d = 25 nm), and a region where the lattice spacing d is set so that the ratio (d / do) is “2”. (D = 50 nm region).

Next, in Comparative Example 1, as shown in FIG. 4 (a), the first polymer consisting of a patterned chemically modified layer 401 (polystyrene graft film) is used by using a fifth polymer block copolymer. A coating film 202 of a polymer block copolymer was formed on the substrate 201 having the region 106 and the second region 107 composed of the exposed surface 201a of the substrate 201 (Si wafer).
The coating film 202 was subjected to thermal annealing at 180 ° C. for 24 hours.

However, in the coating film 202 in Comparative Example 1, when the ratio (d / do) to the natural period do (25 nm) of the polymer block copolymer is “1” (d = 25 nm), and “2” (d = 50 nm) In all cases, a domain structure was observed, but unlike Example 1 to Example 4, hexagonal microdomains were not formed. In Comparative Example 1, the effect of using a chemical registration method such as pattern interpolation was not exhibited.
In the domain structure in this comparative example, since the improvement of the arrangement state of the microdomains was not recognized, the evaluation result is shown as “x” in Table 1.

(Example 5)
In Example 5, the microstructure of the present invention was manufactured. Specifically, the microstructure (porous thin film D and microstructure 21a) using the polymer thin film M was obtained through the steps shown in FIGS. 7A to 7D.

First, in the same manner as in Example 2, the microphase separation structure in which the columnar microdomain 203 made of PMMA is upright with respect to the substrate 201 (oriented in the thickness direction of the polymer thin film M) as shown in FIG. Fabricated on the surface of the substrate 201.
In the patterning, the grating interval is set to d = 36 nm so that the period (d / do) is “2”, which is twice the natural period do (18 nm) of PMMA-b-PMAC11POSS (2). I went there.

  Moreover, the thickness of the coating film of PMMA-b-PMAC11POSS (2) was 40 nm, and thermal annealing was performed at 180 ° C. for 24 hours. As a result, a polymer thin film in which columnar microdomains 203 made of PMMA were regularly arranged in hexagonal form in a continuous phase 204 made of PMAC11POSS was obtained.

  Next, the micro domain 203 was removed by oxygen RIE to obtain a porous thin film D as a microstructure shown in FIG. 7B. Here, the gas pressure of oxygen was 1 Pa, and the output was 20 W. The etching processing time was 90 seconds.

  And when the surface of the porous thin film D was observed using the scanning electron microscope, the columnar micropore H oriented in the thickness direction of the porous thin film D was confirmed over the entire surface of the porous thin film D. It was done. Here, the diameter of the micropore H was about 10 nm. Further, as a result of detailed analysis of the arrangement state of the micropores H, the micropores H are arranged in a hexagonal manner in a state in which the micropores H are oriented in one direction without defects in a region where the surface is chemically patterned with the lattice spacing d. I was able to see.

  Here, a part of the porous thin film D is peeled off from the surface of the substrate 201 with a sharp blade, and a step (thickness of the porous thin film D) between the surface of the substrate 201 and the surface of the porous thin film D is determined by AFM (atom It was about 40 nm when measured by observation with an atomic force microscope.

  The aspect ratio of the obtained micropore H was 4, and a large value that could not be obtained with a spherical microdomain was realized. In addition, it was confirmed that the etching resistance of PMAC11POSS was very excellent because the thickness of the porous thin film D as the fine structure was not substantially different from the thickness of the coating film before RIE.

Next, as shown in FIG. 7C, the pattern of the porous thin film D was transferred to the substrate 201 by etching the substrate 201 using the porous thin film D as a mask. Here, the Si substrate was implemented by dry etching with CF ₄ gas. As a result, the shape and arrangement of the fine holes H in the porous thin film D were successfully transferred to the Si substrate, and a fine structure 21a shown in FIG. 7D was obtained.

(Comparative Example 2)
In Comparative Example 2, as shown in FIG. 2 (c), the PMMA− was formed on the substrate 201 in the same manner as in Example 2 except that the polystyrene graft film (chemically modified layer 401) on the substrate 201 was not patterned. b-PMAC11POSS (2) was applied to a film thickness of 40 nm, and thermal annealing was performed at 180 ° C. for 24 hours to obtain a polymer thin film exhibiting microphase separation. Next, a porous thin film D shown in FIG. 7A was obtained in the same manner as in Example 5 except that the substrate on which this polymer thin film was formed was used.

  And the surface of the porous thin film D was observed using the scanning electron microscope. As a result, although the micropores H of the porous thin film D are microscopically arranged in a hexagonal manner, macroscopically, the regions arranged in the hexagonal form a polygrain structure. It was confirmed that there were many lattice defects.

(Example 6)
In Example 6, a method of manufacturing a magnetic recording medium (bit pattern medium) as a microstructure of the present invention will be described with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 11 is a schematic diagram showing a magnetic recording medium according to the present embodiment.

The configuration of the magnetic recording medium will be described with reference to FIG. This figure shows a schematic diagram of a so-called bit pattern medium (BPM) in which each recording bit is separated.
FIG. 11 is a schematic view showing a magnetic recording medium 300 manufactured according to the present invention. The magnetic recording medium 300 has a disk shape with a diameter of 65 mm and a thickness of 0.631 mm, and has a structure in which a plurality of magnetic layers and other layers are stacked on a substrate 301. A hole 302 having a diameter of 20 mm for fixing the magnetic recording medium 300 to the spindle is provided at the center of the substrate 301.

The recording track 303 is formed concentrically and has a structure in which it is magnetically separated from adjacent tracks by a nonmagnetic material. The outermost surface of the magnetic recording medium 300 is flattened, and the difference in height between the recording track 203 and the non-magnetic region is less than 5 nm.
The magnetic recording medium 300 is also provided with a servo pattern 304 for accessing an area on a desired track and performing a recording / reproducing operation.
In FIG. 11, the servo pattern 304 is schematically shown by a curve, but a fine pattern exists inside. Further, in this embodiment, one round is divided into 200 so that the servo pattern 304 is inserted in each area. Of course, the number of servo patterns is not limited to 200 and needs to be determined from the recording / reproducing characteristics.
Further, the magnetic recording medium 300 can be provided with an inner peripheral portion 305 and an outer peripheral portion 306 in which the recording track 303 and the servo pattern 304 are not formed.

  A manufacturing method (manufacturing process) of the magnetic recording medium 300 will be described. In this manufacturing process, a soft magnetic underlayer (SUL) was first grown on the substrate 201. The material of the substrate 301 is not limited to glass, and a metal such as aluminum, a semiconductor such as silicon, an insulator such as ceramics or polycarbonate, or the like can be selected. The soft magnetic backing layer employs an Fe—Ta—C alloy, and after the sputter deposition in the vacuum chamber, necessary heat treatment was performed.

  It is desirable to give magnetic anisotropy in the radial direction of the medium to the soft magnetic backing layer. Instead of the Fe—Ta—C alloy, other soft magnetic underlayers may be used, and other growth methods other than sputter deposition may be employed. Further, if necessary, an adhesion layer for enhancing the adhesion between the substrate 301 and the soft magnetic backing layer, an intermediate layer for controlling the crystallinity of the soft magnetic backing layer, or the like may be inserted.

  After the formation of the soft magnetic underlayer, the recording layer is subsequently grown by sputter deposition in a vacuum. In this embodiment, a Co—Cr—Pt film is used as the recording layer. This material is characterized by having an easy axis of magnetization in a direction perpendicular to the film surface direction. Therefore, in this embodiment, the sputter deposition conditions are selected so that the axis of magnetic anisotropy is substantially perpendicular to the substrate surface.

The magnetic material used for the recording layer is not limited to the Co—Cr—Pt alloy, and other materials may be used. In particular, a recording layer containing Si called a granular film is compatible with the present invention.
Further, a protective layer was grown on the recording layer for substrate processing. The material used as the protective layer was a silicon nitride (SiN) film. The protective layer is not limited to SiN, and other materials may be used.

  Then, as described in Example 5, the polymer thin film M was formed. Next, a fine structure (porous thin film D and fine structure 21a) using the polymer thin film M was obtained through the steps shown in FIGS. 7A to 7D. Thereafter, a nonmagnetic material is embedded in the groove as necessary. For example, Si-O can be grown from above the substrate and planarized by etch back or chemical mechanical polishing (CMP).

  Further, if necessary, a protective film and a lubricating film (not shown) are further grown to complete the magnetic recording medium 300 shown in FIG. In this example, a bit pattern medium having a structure with excellent regularity over a wide range and few defects by forming a fine structure (continuous phase 204, microdomain 203) on the recording layer as in Example 5. Can be manufactured.

  In this example, the recording layer was processed using the fine structure 21 shown in FIG. 7 as a mask. However, the nanoimprint was performed using the fine structure 21a transferred to the Si substrate 201 produced in Example 7 as a mold. It is also possible to process the recording layer in the process. Alternatively, after processing the substrate 301 shown in FIG. 11 in the same manner as in Example 7, it is possible to grow each magnetic film on the uneven shape of the substrate 301.

DESCRIPTION OF SYMBOLS 21 Fine structure 21a Fine structure 21b Fine structure 106 1st area | region 107 2nd area | region 201 Substrate 201a The surface which the substrate exposed 203 Micro domain 204 Continuous phase 300 Magnetic recording medium 301 Substrate 302 Hole 303 Recording track 304 In servo pattern 305 Peripheral part 306 Peripheral part 401 Chemical modification layer A1 1st segment A2 2nd segment M Polymer thin film do Natural period

Claims (10)

A first step of disposing on a substrate a polymer layer comprising a polymer block copolymer having at least a first segment and a second segment;
The polymer layer is microphase-separated so that a plurality of microdomains having the second segment as a component are regularly arranged along the plane direction of the substrate in the continuous phase having the first segment as a component. A second step of arranging;
In a method for producing a polymer thin film having
Prior to the first step, a chemically modified layer is formed on the substrate so as to correspond to the continuous phase, and the chemical property layer is different from the chemically modified layer so as to correspond to the arrangement of the microdomains. A step of forming a pattern portion to be
The second step includes a step of performing a heat treatment at a specific temperature at which the microphase separation occurs.
The polymer block copolymer has an alkyl chain represented by the following formula — (CH ₂ ) _n — with respect to the second segment containing polymethyl methacrylate and the main chain of the polymer block copolymer (provided that Wherein n is an integer satisfying 5 ≦ n ≦ 24), and the first segment including polymethyl methacrylate having a silsesquioxane skeleton bonded via an organic group including
The method for producing a polymer thin film, wherein the chemically modified layer is made of a polystyrene graft film . The method for producing a polymer thin film according to claim 1, wherein the arrangement period d of the pattern portions is a natural number multiple of the natural period d ₀ of the microdomain.   The difference in chemical properties of the pattern part with respect to the chemically modified layer is that the wettability of the pattern part with respect to the component of the second segment is larger than the wettability of the chemically modified layer. Or the manufacturing method of the polymer thin film of Claim 2.   The method for producing a polymer thin film according to any one of claims 1 to 3, wherein the microdomain is formed in a columnar shape standing upright in a thickness direction of the polymer layer.   The method for producing a polymer thin film according to any one of claims 1 to 3, wherein the microdomain is formed in a lamellar shape standing upright in a thickness direction of the polymer layer. Forming the polymer thin film in which a plurality of the microdomains are arranged in the continuous phase on the substrate by the method for producing a polymer thin film according to any one of claims 1 to 5; ,
Removing one of the continuous phase and the microdomain of the polymer thin film;
A method for producing a fine structure characterized by comprising:   After the step of removing one of the continuous phase and the microdomain of the polymer thin film, the method further comprises a step of etching the substrate using the other of the remaining continuous phase and the microdomain as a mask. The method for producing a fine structure according to claim 6, characterized in that:   A polymer thin film obtained by the method for producing a polymer thin film according to any one of claims 1 to 5.   A fine structure obtained by the method for producing a fine structure according to claim 6.   A magnetic recording medium manufactured by the method for manufacturing a fine structure according to claim 9.

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