JP6015140B2 - Nanoimprint mold and manufacturing method thereof - Google Patents

Description

  The present invention relates to a nanoimprint mold used in a nanoimprint method for forming a fine uneven pattern and a method for producing the same.

  In recent years, especially in semiconductor devices, high speed operation and low power consumption operation have been required due to further progress in miniaturization. Further, a high technology such as integration of functions called a system LSI has been demanded.

  Under such circumstances, the lithography technology, which is the key to producing semiconductor device patterns, has pointed out the limitations of the photolithography method due to the problem of exposure wavelength as device pattern miniaturization progresses.・ The nanoimprint method is attracting attention as a fine patterning method.

  In the nanoimprint method, a nanoimprint mold (template) with a nanometer-size uneven pattern formed in advance on the surface is pressed against a transfer material such as resin applied to the surface of the substrate to be processed, and the transfer material is mechanically deformed to generate unevenness. This is a technology for transferring patterns precisely. Then, for example, by using a patterned transfer material as a resist mask, the substrate to be processed can be finely processed.

  In such a nanoimprint method, once a nanoimprint mold is prepared, the same nanostructure can be easily and repeatedly molded. Therefore, high throughput is obtained and it is economical, and nanoprocessing technology with less harmful waste Therefore, in recent years, applications are not limited to semiconductor devices but in various fields.

  A nanoimprint mold used in the nanoimprint method is required to have pattern dimension stability, chemical resistance, processing characteristics, and the like. In the nanoimprint method, the concave-convex pattern shape of the nanoimprint mold must be faithfully transferred to a transfer material such as a resin. In the case of the optical nanoimprint method, generally, UV light for photocuring is transmitted. A quartz glass substrate is used as a mold substrate.

  The nanoimprint mold manufacturing method is performed by etching a substrate such as quartz glass to form an uneven pattern on the surface of the substrate (see, for example, Patent Document 1). FIG. 3 is a cross-sectional view for explaining a process example of a conventional nanoimprint mold manufacturing method over time.

  First, as shown in FIG. 3 (A), a metal thin film 132 such as chromium (Cr) is formed on a substrate 131 such as quartz glass to be a nanoimprint mold as a hard mask material at the time of substrate etching. An electron beam sensitive resin (electron beam resist) is applied to the substrate, and exposure, development, and the like are performed using an electron beam (EB) lithography technique to form a resist pattern 133.

  Next, as shown in FIG. 3B, the resist pattern 133 is subjected to slimming treatment with oxygen plasma, thereby reducing the thickness and width of the resist pattern. The slimming process in this step is not an indispensable step. For example, it may be determined whether or not to perform the slimming process according to the target resist pattern line width.

  Next, as shown in FIG. 3C, the metal thin film 132 is etched using the slimmed resist pattern 133a as a mask to form the metal thin film pattern 132a. Next, the substrate 131 is etched using the metal thin film pattern 132a as a mask, so that the substrate 131 is formed with a recess 136 as shown in FIG. Next, as shown in FIG. 3E, the resist pattern 133a is peeled and removed. The resist pattern 133a may be removed before the substrate 131 is etched.

  Next, as shown in FIG. 3F, a method is used in which the metal thin film pattern 132a is removed by etching, and the nanoimprint mold 130 in which the concave / convex pattern 137 is provided on the substrate 131 is produced.

JP 2005-345737 A

  However, the nanoimprint mold is manufactured using a bulk process for processing the substrate itself. Therefore, in particular, as the uneven pattern becomes finer, so-called microloading becomes more prominent in the etching process, and it tends to become difficult to maintain the processing depth and the uniformity of the processing shape.

  Further, in the bulk process for processing the substrate itself, a process for manufacturing a mask with a fine pattern and processing the substrate itself using the mask is required. It tends to be difficult to achieve reduction.

  The present invention was devised under such circumstances, and its purpose is to provide excellent dimensional accuracy of the concavo-convex part of the nanoimprint mold having a fine concavo-convex pattern, and to reduce the mold manufacturing cost. An object of the present invention is to provide a nanoimprint mold and a method for manufacturing the same.

In order to solve the above-described problems, a method for manufacturing a nanoimprint mold of the present invention includes a step of preparing a substrate having a first main surface portion formed of a plane, and a direct or intermediate method on the first main surface portion of the substrate. A resist pattern forming step of forming a convex resist body in a predetermined pattern through the film; and a side surface and an upper surface of the convex resist body and a first main surface portion of the substrate or an upper surface of the intermediate film so as to cover the surface. possess a film forming step of depositing a Kutsugaemaku, wherein the coating film is formed by ALD (atomic layer deposition), the covering layer is composed of an atomic layer of the plural layers, the first layer Is operated at a first temperature _TL lower than the glass transition temperature Tg of the resist constituting the convex resist body, and the first atomic layer after deposition is deposited. higher than the temperature T _L of time It is annealed in degrees T _H1, thereafter, the second and subsequent layers of atomic layer are sequentially deposited in an atmosphere of deposition temperature T _L at the time of depositing the first layer of the atomic layer, after deposition completion, when depositing configured so that annealed at a temperature T _L is higher than the temperature T _H1.

Further, the method for producing a nanoimprint mold of the present invention comprises a step of preparing a substrate having a first main surface portion comprising a plane, and a convex resist directly on the first main surface portion of the substrate or via an intermediate film. A resist pattern forming step for forming a body in a predetermined pattern, and a film portion for depositing a coating film so as to cover the side surface and the upper surface of the convex resist body and the first main surface portion or the upper surface of the intermediate film of the substrate And the coating film is formed by an ALD method (atomic layer deposition method), and the coating film is composed of a plurality of atomic layers, and is used when depositing the first atomic layer. The temperature is operated at a first temperature T _L lower than the glass transition temperature Tg of the resist constituting the convex resist body, and the first atomic layer after deposition is higher than the temperature T _L at the time of deposition. is annealed at a temperature T _H1, After mowing, configured to sequentially deposit the second layer and subsequent atomic layer in an atmosphere of deposition higher producing temperature T _H2, than the temperature T _L at the time of depositing the first layer of the atomic layer.

Further, the method for producing a nanoimprint mold of the present invention comprises a step of preparing a substrate having a first main surface portion comprising a plane, and a convex resist directly on the first main surface portion of the substrate or via an intermediate film. A resist pattern forming step for forming a body in a predetermined pattern, and a film portion for depositing a coating film so as to cover the side surface and the upper surface of the convex resist body and the first main surface portion or the upper surface of the intermediate film of the substrate A coating step, wherein the coating film is formed by an ALD method (atomic layer deposition method), the coating film is composed of one atomic layer, and the one atomic layer is deposited. The temperature is operated at a first temperature T _L lower than the glass transition temperature Tg of the resist constituting the convex resist body, and one atomic layer after deposition is a temperature higher than the temperature T _L at the time of deposition. It is annealed at a T _H1 Configured.

  Further, as a preferred embodiment of the method for producing a nanoimprint mold of the present invention, the method for forming a convex resist body in the resist pattern formation step is an electron beam (EB) lithography method, a photolithographic method, or a nanoimprint method. Is done.

The nanoimprint mold of the present invention is a nanoimprint mold for transferring a concavo-convex transfer pattern to the transfer layer by being pressed against the transfer layer, and the nanoimprint mold includes a substrate having a first main surface portion formed of a plane, on the first major surface portion, it possesses a convex resist body located through the middle between the film, a coating layer disposed to cover the convex resist bodies, wherein the intermediate film, Si-based, Ta-based, is any layer of Cr-based, has a function of improving the adhesion between the substrate and the coating film, or electrically conductive, or by organic both of these functions It is comprised so that it may become.

  As a preferred embodiment of the nanoimprint mold of the present invention, the coating film is configured as an ALD film (atomic layer deposition film).

  The method for producing a nanoimprint mold of the present invention includes a step of preparing a substrate having a first main surface portion formed of a plane, and a convex resist body on the first main surface portion of the substrate directly or via an intermediate film. A resist pattern forming process for forming a predetermined pattern, and a film part forming process for depositing a coating film so as to cover the side surface and the upper surface of the convex resist body and the first main surface part or the upper surface of the intermediate film of the substrate The nanoimprint mold can be easily manufactured without requiring any etching including the step of digging the substrate. In particular, in the present invention, since the step of digging the substrate is unnecessary, the dimensional accuracy of the uneven portion of the nanoimprint mold is excellent, and the mold manufacturing cost can be reduced.

FIGS. 1A to 1C are cross-sectional views for explaining a process example of the nanoimprint mold manufacturing method (first embodiment) of the present invention over time. FIGS. 2A to 2D are cross-sectional views for explaining a process example of the nanoimprint mold manufacturing method (second embodiment) of the present invention over time. FIG. 3 is a cross-sectional view for explaining a process example of a conventional nanoimprint mold manufacturing method over time.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited to the form demonstrated below, In the range which does not deviate from a technical thought, it can implement in various deformation | transformation. In the accompanying drawings, the vertical and horizontal scales may be exaggerated for the sake of explanation, and the actual scales may differ.

  First, the method for producing the nanoimprint mold of the present invention will be described with reference to FIGS. 1 and 2 so that the configuration of the nanoimprint mold of the present invention can be understood more easily.

<Method for Producing Nanoimprint Mold (First Embodiment)>
FIGS. 1A to 1C are cross-sectional views for explaining a process example of the first embodiment of the method for producing a nanoimprint mold of the present invention over time.

  The manufacturing method of the nanoimprint mold of the present invention in the first embodiment includes (1) a step of preparing a substrate having a first main surface portion consisting of a plane, and (2) directly or intermediately on the first main surface portion of the substrate. A resist pattern forming step of forming a convex resist body in a predetermined pattern through the film; and (3) covering the side surface and top surface of the convex resist body and the first main surface portion of the substrate or the top surface of the intermediate film. And a film portion forming step of depositing a coating film on the substrate.

  Hereinafter, each step will be sequentially described.

(1) Step of Preparing a Substrate Having a First Main Surface Part That is a Plane As shown in FIG. 1A, a substrate 10 that serves as a base of a nanoimprint mold is prepared. A first main surface portion 11a is formed on the main surface 11 on one side of the substrate 10, and the first main surface portion 11a is a plane on which a convex resist body described later can be formed. In FIG. 1 (A), an example is shown in which the entire area of the principal surface 11 on one side of the substrate 10 constitutes a first principal surface portion 11a composed of a flat surface, but is not limited to this configuration. For example, the substrate 10 can be a so-called mesa structure in which only the area where the convex resist body is provided constitutes the first main surface portion of the flat surface partially protruding.

  The material of the substrate 10 can be appropriately selected. For example, when the nanoimprint mold is used as a so-called mold for optical imprinting, the substrate 10 is formed using a transparent base material that can transmit irradiation light. Further, glass such as quartz glass, silicate glass, calcium fluoride, magnesium fluoride, and acrylic glass, resin such as polycarbonate, polypropylene, and polyethylene, or any laminated material thereof can be used. For example, when the nanoimprint mold is used as a so-called thermal imprint mold, the substrate 10 does not necessarily need to be a transparent base material, for example, a metal such as nickel, titanium, or aluminum, or a semiconductor such as silicon or gallium nitride. May be used.

  The thickness of the substrate 10 serving as the base of the nanoimprint mold can be set in consideration of the strength of the substrate, the handleability, and the like, and can be set as appropriate within a range of about 300 μm to 10 mm, for example. Further, as described above, the substrate 10 may have a so-called mesa structure in which the first main surface portion 11a on which the convex resist body is formed is a flat surface. The number of stages of the mesa structure is not limited to one but may be a plurality of stages.

(2) Resist Pattern Forming Step Next, as shown in FIG. 1B, a convex resist body 30 is formed in a predetermined pattern on the first main surface portion 11a of the substrate 10 via the intermediate film 20. A resist pattern forming step is performed. Although the intermediate film 20 is interposed in the illustrated example, the convex resist body 30 is formed in a predetermined pattern directly on the first main surface portion 11 of the substrate 10 without the intermediate film 20 being interposed. You may do it.

  The pattern formation of the convex resist body 30 can be formed by an electron beam (EB) lithography method, a photolithographic method, or a nanoimprint method.

  When the electron beam (EB) lithography method is used as a first technique, a resist forming step of forming an electron beam sensitive resin film on the intermediate film 20 of the substrate 10 is performed, and then the formed electron beam sensitive Electron beam drawing is performed on the conductive resin film so as to form a desired pattern.

  After the electron beam drawing is completed, a resist developing process for developing the electron beam sensitive resin film is performed. For example, when a positive electron beam sensitive resin film is used, it remains as a resist in a state where an unirradiated portion is not decomposed, and a convex resist body 30 is formed in a predetermined pattern (a negative electron beam sensitive resin). When a film is used, the irradiated portion remains as a resist without being decomposed, and a pattern opposite to the positive type is formed).

  As a second method, when the photolithography method is used, a resist forming step for forming a photosensitive resin film is performed on the intermediate film 20 of the substrate 10, and then the desired photosensitive resin film is applied to the desired photosensitive resin film. The exposure operation is performed through the mask pattern so as to form the pattern. After the exposure operation is completed, a resist development process for developing the photosensitive resin film is performed. For example, when a positive photosensitive resin film is used, the unexposed portion remains as a resist without being decomposed, and the convex resist body 30 is formed in a predetermined pattern (using a negative photosensitive resin film). In this case, the exposed portion remains as a resist without being decomposed, and a pattern opposite to the positive type is formed).

  As a third method, when the nanoimprint method is used, for example, a photocurable resin material is supplied and disposed as an object to be transferred on the intermediate film 20 of the substrate 10 by a dispenser, an inkjet, or the like. Next, a mold having a desired concavo-convex structure is brought into contact with the disposed resin material, and pressure is applied as necessary (so-called mold pressing step). In this state, the resin material becomes a resin layer having an uneven structure, and the resin material is cured by irradiating the resin layer with ultraviolet rays (so-called resin curing step). Next, by separating the mold from the resin material, a concavo-convex structure in which the concavo-convex structure of the mold is inverted is formed on the intermediate film 20 of the substrate 10 in a predetermined pattern, and the pattern of the convex resist body 30 is formed. The so-called residual film may be removed by oxygen ashing or the like.

  The convex resist body 30 referred to in the present invention refers to a structure including a resin material as a main component, and is a concept including a material called a so-called permanent resist.

  When the nanoimprint mold is used as a so-called mold for optical imprinting, it is desirable that the convex resist body 30 is made of a material that easily transmits irradiation light.

  The intermediate film 20 provided on the substrate 10 as necessary is, for example, a film having a function of improving the adhesion between the substrate 10 and a coating film 40 described later, a film having conductivity, or both of them. It is preferable that it is comprised from the film | membrane etc. which have these functions. The intermediate film 20 may be configured as a laminated film having two or more layers. For example, the conductive intermediate film 20 can be operated so as to guide electrons during pattern drawing in electron beam (EB) lithography. However, even in electron beam (EB) lithography, it is possible to draw a pattern with a conductive film formed on the surface of the electron beam sensitive resin film, and the presence of the conductive intermediate film 20 is essential. is not. Further, when the adhesion between the substrate 10 and the coating film 40 is good, the intermediate film 20 may be omitted.

  In the case where the intermediate film 20 is provided, specific materials include Si-based, Ta-based, and Cr-based films. The film thickness is usually 50 nm or less, particularly about several nm to 50 nm.

  When the nanoimprint mold is used as a so-called mold for optical imprinting, it is desirable that the intermediate layer 20 be a transparent material that can transmit irradiation light.

  The pattern form of the convex resist body 30 is, for example, a so-called line-and-space form in which the concavo-convex shape is sequentially extended in the longitudinal direction, a form in which the dot shape is dispersed in a predetermined pattern, a hole Any of a form in which the shapes are dispersed in a predetermined pattern, a form in which these individual shapes are combined, a special three-dimensional structure other than these, or the like may be used. As a specific example, it is good also as a structure which comprises a micro lens.

(3) Film Portion Formation Step Next, as shown in FIG. 1C, the side surfaces 32 and the upper surface 31 of the convex resist body 30 and the upper surface of the intermediate film 20 (if the intermediate film 20 is not provided, the substrate A film part forming step of depositing the coating film 40 so as to cover the ten first main surface parts 11a) is performed.

  The coating film 40 is not particularly limited as long as a series of films are formed in layers along the surface to be deposited, but preferably, an ALD method (atomic layer deposition method) is used. A formed atomic layer deposition film is desirable. The surface to be deposited may be a surface of any shape such as an uneven surface or a curved surface. By using the ALD method, a film can be accurately formed at a low temperature. Furthermore, step coverage is also very good.

  The covering film 40 may be composed of one atomic layer or may be composed of two or more atomic layers.

When the coating film 40 is composed of one atomic layer, the temperature at which one atomic layer is deposited does not damage the convex resist body 30 whose main component is a resin. It is desirable to operate at a first temperature T _L , which is sufficiently lower than the glass transition temperature Tg of the constituent resist (for example, 20 to 100 ° C., more preferably room temperature).

Thereafter, the deposited atomic layer is preferably annealed at a temperature T _H1 higher than the temperature T _L during deposition. As a result, the film strength of the atomic layer itself can be increased, and the adhesion with the bonded product can be increased.

The temperature T _H1 can be appropriately selected according to the material constituting the atomic layer, but is set to a temperature range of 200 to 800 ° C., for example.

When the coating film 40 is composed of two or more atomic layers, the temperature at which the first atomic layer is deposited does not damage the convex resist body 30 mainly composed of a resin. It is desirable to operate at a first temperature T _L (for example, 20 to 100 ° C., more preferably room temperature) that is sufficiently lower than the glass transition temperature Tg of the resist that forms the resist 30.

Thereafter, the first atomic layer after deposition is preferably annealed at a temperature T _H1 higher than the temperature T _L during deposition. As a result, the first atomic layer can increase the film strength of the atomic layer itself or increase the adhesion with the bonded product. The temperature T _H1 can be appropriately selected according to the material constituting the atomic layer, but is set to a temperature range of 200 to 800 ° C., for example.

In this way, after forming a strong first atomic layer, the second and subsequent atomic layers are deposited in a deposition atmosphere at a temperature T _H2 higher than the temperature T _L when the first atomic layer is deposited. It is desirable to deposit sequentially. This is to increase the strength of the atomic layer, increase the adhesion, and increase the efficiency of the process. The temperature T _H2 can be appropriately selected according to the material constituting the atomic layer, but is set to a temperature range of 80 to 600 ° C., for example. The temperature T _H2 may be the same as the annealing temperature T _H1 of the first atomic layer.

The second and subsequent atomic layers are deposited (film formation) at a temperature approximately equal to the temperature _TL for depositing the first atomic layer, and the temperature at which the second atomic layer is deposited after the deposition (film formation) is completed. Annealing may be performed at a temperature T _H1 higher than T _L.

  The film thickness of the coating film 40 thus formed is, for example, about several nm to 500 nm.

  Specific examples of the material constituting the coating film 40 include Si-based, Al-based, and Ta-based films.

  When the nanoimprint mold is used as a so-called photoimprint mold, it is desirable that the coating film 40 be a transparent material that can transmit irradiation light.

<Nanoimprint mold manufacturing method (second embodiment)>
Next, a second embodiment of the manufacturing method of the nanoimprint mold will be described.
2 (A) to 2 (D) are cross-sectional views illustrating the process example of the second embodiment of the method for producing a nanoimprint mold of the present invention over time.

  The second embodiment shown in FIG. 2 is different from the first embodiment shown in FIG. 1 described above in that the slimming of the convex resist body 30 is performed after the resist pattern forming step for forming the convex resist body 30. The slimming process (FIG. 2 (C)) which performs is added. 2A to 2B and the process shown in FIG. 1A to FIG. 1B are the same steps, and therefore, FIG. 2A to FIG. The description of the process shown in FIG.

  In the slimming process, as shown in FIG. 2C, the convex resist body 30a is slimmed by processing the convex resist body 30 with, for example, oxygen plasma, and slimmed as shown in FIG. 2C. Is formed.

  In this specification, the slimming is to reduce the width of the pattern of the convex resist body 30 and reduce the film thickness by wet etching or dry etching (including oxygen plasma treatment). For example, by performing slimming by oxygen plasma treatment, the width of the convex body 50 can be changed without changing the pattern pitch of the convex body 50 as shown in FIG.

  2D is substantially the same as the above-described film part forming step shown in FIG. 1C, and the description thereof is omitted here.

<Description of nanoimprint mold>
Through the above steps, a nanoimprint mold as shown in FIGS. 1C and 2D is formed.

  The nanoimprint mold of the present invention is used for performing a nanoimprint method. For example, a mold for transferring an uneven transfer pattern to a transfer layer by being pressed against a transfer layer such as a resin provided on a substrate to be processed. It is. A transfer layer such as a resin may be initially provided on the nanoimprint mold side instead of the substrate to be processed.

  The nanoimprint mold as the first embodiment includes, for example, as shown in FIG. 1C and FIG. 2D, a substrate 10 having a first main surface portion 11a composed of a plane, and the first main surface portion 11a. A convex resist body 30 (30a) standing on the intermediate film 20 and a coating film 40 formed so as to cover the convex resist body 30 (30a). Has been. The convex body 50 contributing to the formation of the concave-convex transfer pattern is formed by the convex resist body 30 (30a) and the coating film 40 formed so as to cover the convex resist body 30 (30a).

  The intermediate film 20 is provided as necessary. Without providing the intermediate film 20, the convex resist body 30 (30 a) and the coating film 40 are directly formed on the first main surface portion 11 a of the substrate 10. You may make it have.

  The convex body 50 in the present invention is not integrally formed so as to dig out the main surface of the substrate 10, but is directly on the substrate 10 as a member different from the substrate 10 and the intermediate film 20, or It exists in the state piled up through the intermediate film 20. Accordingly, there is a bonding interface at a position where the bottom of the convex body (50) and the substrate 10 or the intermediate film 20 are bonded.

  The other members in the present invention are not judged based on the coincidence / non-coincidence of materials, but are judged based on whether or not there is a bonded interface, and only those that are integrally formed are excluded. This is the purpose. The mold of the present invention in which the bonding interface exists is a convex body from the bonding interface when the uneven pattern of the no-imprint mold deteriorates and is not practically used, or when the specification of the uneven pattern is changed and the pattern is recreated. By removing 50 (the convex resist body 30 (30a) and the coating film 40), the substrate 10 can be reused.

  Furthermore, the nanoimprint mold of the present invention has a configuration in which the convex resist body 30 (30a) remains as a so-called core material inside the convex body 50.

  The shape, material, thickness, etc. of the substrate 10 constituting the nanoimprint mold of the present invention, the characteristics, material, film thickness, etc. of the intermediate film 20 that can be provided as necessary, the configuration, material, etc. of the coating film 40 Is described when the above-described method for producing a nanoimprint mold is described, so refer to the description there.

<Other Embodiments of Nanoimprint Mold>
As another embodiment, only the intermediate film 20 located at the base of the convex resist bodies 30 and 30a shown in FIGS. 1B and 2C is left, and the convex resist bodies 30 and 30a are erected. The intermediate film 20 is removed from the unexposed part by etching or the like, and the intermediate film 20 is made of a material such as Cr that easily causes a contrast difference depending on the presence or absence of the intermediate film. Thereafter, the coating film 40 is deposited so as to cover the convex resist bodies 30 and 30a.

  By adopting such a configuration, the accuracy of positional accuracy measurement where the convex resist bodies 30 and 30a are erected and the sensitivity of defect inspection are improved by irradiating the nanoimprint mold with inspection light. be able to.

  Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example 1
A synthetic quartz glass substrate having an outer shape of 6 inches square and a thickness of 0.25 inches was prepared as the light transmissive substrate 10. A Cr film 20 (intermediate film 20) having a film thickness of 6 nm was formed on one main surface of the prepared substrate 10 by sputtering with Cr. In this embodiment, the Cr film 20 mainly functions as an adhesion film and a conductive film.

  Next, an electron beam sensitive resin (electron beam resist) is applied on the Cr film 20, and a resist pattern (convex shape) having a resist thickness of 60 nm in a line-and-space pattern form with a pattern width of 30 nm and a pitch of 140 nm is formed by electron beam drawing. The pattern of the resist body 30) was formed.

A SiO ₂ film is formed by the ALD method so as to cover the side surface and upper surface of the convex resist body 30 constituting the resist pattern thus formed, and the upper surface of the Cr film 20 (intermediate film 20). _{2 A} coating film (coating film) was formed.

When forming the SiO ₂ film by the ALD method, the first temperature T _L (film formation temperature) when depositing the first atomic layer was set to room temperature (23 ° C.). Thereafter, the deposited first atomic layer was annealed at a temperature T _H1 = 200 ° C. higher than the temperature T _L during deposition. After forming the first atomic layer in this way, the second and subsequent atomic layers are sequentially deposited at a temperature T _H2 (deposition temperature) = 350 ° C. to form a SiO ₂ coating film (coating film). Then, a nanoimprint mold according to Example 1 was produced.

  It was confirmed that the dimensional accuracy of the concavo-convex portion of the nanoimprint mold of the first example formed in this way was extremely excellent. That is, the variation in the height of the convex portion was an error within ± 1% with respect to the standard design dimension. Similarly, the variation in the width of the convex portion was an error within ± 2% with respect to the standard design dimension.

(Example 2)
A synthetic quartz glass substrate having an outer shape of 6 inches square and a thickness of 0.25 inches was prepared as the light transmissive substrate 10. On one main surface of the prepared substrate 10, SiO ₂ was deposited by sputtering to form a 10 nm thick SiO ₂ film 20 (intermediate film 20). The SiO ₂ film 20 in this embodiment mainly functions as an adhesion film.

Next, an electron beam sensitive resin (electron beam resist) is applied on the SiO ₂ film 20, and a resist pattern (convex pattern) having a resist thickness of 60 nm in the form of a line and space pattern with a pattern width of 30 nm and a pitch of 140 nm is formed by electron beam drawing. Pattern of the resist-like body 30).

A SiO ₂ film is formed by the ALD method so as to cover the side surface and upper surface of the convex resist body 30 constituting the resist pattern thus formed, and the upper surface of the SiO ₂ film, and a SiO ₂ coating film having a thickness of 20 nm ( Coating film) was formed.

When forming the SiO ₂ film by the ALD method, the first temperature T _L (film formation temperature) when depositing the first atomic layer was set to room temperature (23 ° C.). Thereafter, the deposited first atomic layer was annealed at a temperature T _H1 = 200 ° C. higher than the temperature T _L during deposition. After forming the first atomic layer in this way, the second and subsequent atomic layers are sequentially deposited at a temperature T _H2 (deposition temperature) = 350 ° C. to form a SiO ₂ coating film (coating film). Then, a nanoimprint mold according to Example 2 was produced.

  It was confirmed that the dimensional accuracy of the concavo-convex portion of the nanoimprint mold of the second example formed in this way was extremely excellent. That is, the variation in the height of the convex portion was an error within ± 1% with respect to the standard design dimension. Similarly, the variation in the width of the convex portion was an error within ± 2% with respect to the standard design dimension.

  From the above results, the effect of the present invention is clear. That is, the method for producing a nanoimprint mold of the present invention includes a step of preparing a substrate having a first main surface portion formed of a plane, and a convex resist directly on the first main surface portion of the substrate or via an intermediate film. A resist pattern forming step for forming a body in a predetermined pattern, and a film portion for depositing a coating film so as to cover the side surface and the upper surface of the convex resist body and the first main surface portion or the upper surface of the intermediate film of the substrate Therefore, the nanoimprint mold can be easily manufactured without requiring any etching process including the process of digging the substrate. In particular, in the present invention, since the step of digging the substrate is unnecessary, the dimensional accuracy of the uneven portion of the nanoimprint mold is excellent, and the mold manufacturing cost can be reduced.

  The present invention can be used in technical fields that require various fine processing, and can be applied to, for example, the manufacture of electronic components including a semiconductor integrated circuit and high-density recording media.

DESCRIPTION OF SYMBOLS 10 ... Board | substrate 11 ... Main surface 11a ... 1st main surface part 20 ... Intermediate film 30, 30a ... Convex-shaped resist body 40 ... Cover film 50 ... Convex-shaped body

Claims (6)

Preparing a substrate having a first main surface portion comprising a plane;
A resist pattern forming step of forming a convex resist body in a predetermined pattern directly or via an intermediate film on the first main surface portion of the substrate;
Have a, a film forming step of depositing a coating film to cover the side and top surfaces, and the upper surface of the first main surface or the intermediate layer of the substrate of the convex resist bodies,
The coating film is formed by an ALD method (atomic layer deposition method),
The coating film is composed of a plurality of atomic layers, and the first temperature T _L is lower than the glass transition temperature Tg of the resist constituting the convex resist body when the first atomic layer is deposited. The first atomic layer after deposition is annealed at a temperature T _H1 higher than the deposition temperature T _L , and then the second and subsequent atomic layers are converted into the first atomic layer. was successively deposited in an atmosphere of deposition temperature T _L at the time of depositing, after deposition completion, production method of a nanoimprint mold according to claim Rukoto is annealed at a temperature T _H1 than the temperature T _L at the time of depositing. Preparing a substrate having a first main surface portion comprising a plane;
A resist pattern forming step of forming a convex resist body in a predetermined pattern directly or via an intermediate film on the first main surface portion of the substrate;
A film portion forming step of depositing a coating film so as to cover the side surface and the upper surface of the convex resist body, and the first main surface portion of the substrate or the upper surface of the intermediate film,
The coating film is formed by an ALD method (atomic layer deposition method),
The coating film is composed of a plurality of atomic layers, and the first temperature T is lower than the glass transition temperature Tg of the resist constituting the convex resist body when the first atomic layer is deposited. _L The first atomic layer after deposition is deposited at a temperature T during deposition. _L Higher temperature T _H1 After that, the temperature T at which the first atomic layer is deposited on the second and subsequent atomic layers _L Higher temperature T _H2 A method for producing a nanoimprint mold, comprising sequentially depositing under a deposition atmosphere. Preparing a substrate having a first main surface portion comprising a plane;
A resist pattern forming step of forming a convex resist body in a predetermined pattern directly or via an intermediate film on the first main surface portion of the substrate;
A film portion forming step of depositing a coating film so as to cover the side surface and the upper surface of the convex resist body, and the first main surface portion of the substrate or the upper surface of the intermediate film,
The coating film is formed by an ALD method (atomic layer deposition method),
The coating film is composed of one atomic layer, and a temperature at which the one atomic layer is deposited is a first temperature T lower than the glass transition temperature Tg of the resist constituting the convex resist body. _L One atomic layer after deposition is deposited at a temperature T during deposition. _L Higher temperature T _H1 A method for producing a nanoimprint mold, wherein the annealing process is carried out. The method for producing a nanoimprint mold according to any one of claims 1 to 3 , wherein the method of forming a convex resist body in the resist pattern forming step is an electron beam (EB) lithography method, a photolithographic method, or a nanoimprint method. . A nanoimprint mold for transferring an uneven transfer pattern to the transfer layer by being pressed against the transfer layer,
The nanoimprint mold is
A substrate having a first main surface portion formed of a plane;
On the first major surface, a convex resist body located through the middle between the membranes,
Have a, a coating layer disposed to cover the convex resist bodies,
The intermediate film is a Si-based film, a Ta-based film, or a Cr-based film, and has a function of improving adhesion between the substrate and the coating film, or has conductivity, or nanoimprint mold, characterized in that the chromatic these both functions. The nanoimprint mold according to claim 5 , wherein the coating film is composed of an ALD film (atomic layer deposition film).

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