JP2015032792A - Defect correction method, inspection method and manufacturing method of template for nanoimprint lithography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a defect correction method of a template for NIL capable of detecting minute black defects, and to provide an inspection method and a manufacturing method thereof.SOLUTION: A defect correction method of a template for NIL includes a first template preparation step of preparing a first template, an inspection template manufacturing step of manufacturing an inspection template by imprint transfer using the first template, an inspection template inspection step of inspecting a white defect of the inspection template, a first template defect confirmation step of confirming the black defect of the first template transferring the white defect, when the white defect is detected on the inspection template, and a first template defect correction step of correcting the black defect, when the black defect is detected on the first template.

Description

  The present invention relates to defect correction and inspection of templates for nanoimprint lithography.

  Nanoimprint lithography is a method in which a template having a desired pattern on the surface is brought into close contact with the curable resin layer of the transfer object and an external stimulus such as heat or light is applied to transfer the pattern to the surface of the transfer object. It is. Nanoimprint lithography can form a pattern by a simple method, and has recently been shown to be capable of transferring ultrafine patterns of several tens to several nanometers. Therefore, nanoimprint lithography is expected as a candidate for next-generation lithography technology.

  Among nanoimprint lithography, optical nanoimprint lithography has advantages such as higher throughput, no dimensional change due to temperature, and easy template alignment compared to thermal nanoimprint lithography. Therefore, in recent years, a template for optical nanoimprint lithography has been developed.

  In nanoimprint lithography, a high-precision concave / convex pattern of an original template is transferred by being pressed against a curable resin layer of a transfer target. If there is a defect in the template, the defect is also transferred to all of the transfer target. . In addition, the template is not a quadruple mask such as a conventional photomask, but an equal magnification mask, and there is a specific problem that even a minute defect is transferred to a transfer target. Therefore, the template is required to be defect-free.

  However, in recent years, miniaturization of patterns has been demanded, and it has become difficult to detect minute defects. As a defect inspection method, for example, a method of inspecting with an electron beam or light is known. However, in the electron beam inspection, a defect smaller than the beam size cannot be resolved. Because there are few, it is difficult to detect. Further, in the optical inspection, the difference in gradation between the normal part and the defective part is small, and the detection sensitivity is lower than that of the electron beam inspection, so that the detection is further difficult.

  Patent Document 1 discloses a method for forming a resist pattern on an inspection substrate by imprinting using a template and inspecting the presence or absence of the defect in the resist pattern for the purpose of efficiently inspecting the defect of the template. Therefore, a template defect inspection method has been proposed in which the inspection imprinting conditions are different from the processing conditions of the substrate to be processed. In this method, it is possible to suppress the occurrence of defects due to the imprint process and to efficiently inspect the defects due to the template. However, this is not a technique related to a micro defect inspection method.

JP 2012-243799 A

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a template defect correction method, inspection method, and manufacturing method for nanoimprint lithography capable of detecting minute black defects.

In order to solve the above-described problems, the present invention provides a defect correction method for a template for nanoimprint lithography, comprising: a first template preparation step for preparing a first template; and imprint transfer using the first template. An inspection template manufacturing step for manufacturing an inspection template, an inspection template inspection step for inspecting a white defect portion of the inspection template, and the white defect portion when the white defect portion is detected in the inspection template. A first template defect confirmation step for confirming a black defect portion of the first template to which the defect portion is transferred, and a first template for correcting the black defect portion when the black defect portion is detected in the first template There is provided a defect correcting method for a template, comprising a defect correcting step.
Hereinafter, nanoimprint lithography may be referred to as NIL.

  According to the present invention, by detecting the black defect portion of the first template with the white defect portion of the inspection template, even if the first template has a minute black defect portion that is difficult to detect, it can be detected with high sensitivity. Is possible.

  In the said invention, it is preferable that the said test template preparation process has a defect emphasis process which emphasizes the said white defect part. This is because the defect detection sensitivity can be improved.

  In the present invention, the inspection template preparation step includes a lamination step of laminating a hard mask layer and a resin layer on the inspection substrate, and the first template is adhered to the resin layer, and the resin layer is cured. After that, the first template is peeled off, and the transfer step for forming the resin layer having a concavo-convex pattern on the surface, and the concave portion of the concavo-convex pattern of the resin layer are etched until the hard mask layer is exposed. A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed; a third etching step of etching the exposed portion of the inspection substrate; and removing the hard mask layer A hard mask layer removing step, and in the defect emphasizing step, transfer by imprinting using the first template is performed. By than when making a second template, it is preferable to increase the etching time in the first etching step or the second etching step. By extending the etching time of the resin layer or the hard mask layer, the exposed portion of the inspection substrate can be increased, and the white defect portion of the inspection template can be emphasized with respect to the black defect portion of the first template. Is possible.

  In the above case, in the defect emphasizing step, the thickness of the remaining film portion of the concavo-convex pattern of the resin layer may be made thicker than when the second template is produced by imprint transfer using the first template. preferable. By increasing the thickness of the remaining film portion of the concavo-convex pattern of the resin layer, the etching time of the resin layer can be extended. Accordingly, as described above, the exposed portion of the inspection substrate can be enlarged, and the white defect portion of the inspection template can be emphasized with respect to the black defect portion of the first template.

  In the present invention, the inspection template preparation step includes a lamination step of laminating a hard mask layer and a resin layer on the inspection substrate, and the first template is adhered to the resin layer, and the resin layer is cured. After that, the first template is peeled off, and the transfer step for forming the resin layer having a concavo-convex pattern on the surface, and the concave portion of the concavo-convex pattern of the resin layer are etched until the hard mask layer is exposed. A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed; a third etching step of etching the exposed portion of the inspection substrate; and removing the hard mask layer A hard mask layer removing step, and in the defect emphasizing step, the resin layer is applied to the resin layer during or after the transfer step. It is also preferable to irradiate the child or ultraviolet radiation. The resin layer can be shrunk by electron beam or ultraviolet irradiation. As a result, the exposed portion of the inspection substrate can be enlarged, and the white defect portion of the inspection template can be emphasized with respect to the black defect portion of the first template.

  The present invention is also a method for inspecting a template for NIL, which is a method for preparing an inspection template by a first template preparation step for preparing a first template and imprint transfer using the first template. A template inspection process including a template manufacturing process and an inspection template inspection process for inspecting a white defect portion of the inspection template, and inspecting a black defect portion of the first template with a white defect portion of the inspection template. The method for inspecting a template is characterized in that the inspection template preparation step includes a defect emphasis step for emphasizing the white defect portion.

  According to the present invention, in order to emphasize the white defect portion, the first template has a small black defect portion that is difficult to detect by inspecting the black defect portion of the first template with the white defect portion of the inspection template. Even so, it is possible to detect with high sensitivity.

  In the said invention, the said test template preparation process was made to adhere | attach the said 1st template on the said resin layer, the lamination process which laminates | stacks a hard mask layer and a resin layer on the board | substrate for an inspection, and hardened | cured the said resin layer. Thereafter, the first template is peeled off, the transfer step for forming the resin layer having a concavo-convex pattern on the surface, and the first etching step for etching the concave portion of the concavo-convex pattern of the resin layer until the hard mask layer is exposed. A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed; a third etching step of etching the exposed portion of the inspection substrate; and removing the hard mask layer. A hard mask layer removal step, and in the defect emphasis step, transfer by imprint using the first template Therefore than when making a second template, it is preferable to increase the etching time in the first etching step or the second etching step. As described above, by extending the etching time of the resin layer or the hard mask layer, the exposed portion of the inspection substrate can be increased, and the white defect portion of the inspection template is compared with the black defect portion of the first template. Can be emphasized.

  In the above case, in the defect emphasis step, it is preferable that the remaining film portion of the uneven pattern of the resin layer is made thicker than when the second template is produced by imprint transfer using the first template. As described above, the etching time of the resin layer can be extended by increasing the thickness of the remaining film portion of the uneven pattern of the resin layer. As a result, the exposed portion of the inspection substrate can be enlarged, and the white defect portion of the inspection template can be emphasized with respect to the black defect portion of the first template.

  In the present invention, the inspection template preparation step includes a lamination step of laminating a hard mask layer and a resin layer on the inspection substrate, and the first template is adhered to the resin layer, and the resin layer is cured. After that, the first template is peeled off, and the transfer step for forming the resin layer having a concavo-convex pattern on the surface, and the concave portion of the concavo-convex pattern of the resin layer are etched until the hard mask layer is exposed. A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed; a third etching step of etching the exposed portion of the inspection substrate; and removing the hard mask layer A hard mask layer removing step, and in the defect emphasizing step, the resin layer is applied to the resin layer during the transfer step or after the transfer step. It is also preferable to irradiate the child or ultraviolet radiation. As described above, the resin layer can be contracted by irradiation with an electron beam or ultraviolet rays. As a result, the exposed portion of the inspection substrate can be enlarged, and the white defect portion of the inspection template can be emphasized with respect to the black defect portion of the first template.

Furthermore, the present invention provides a method for manufacturing a template for NIL, comprising a correcting step for performing the above-described template defect correcting method.
In the present invention, a defect-free template can be obtained by performing the above-described template defect correction method.

  Further, the present invention is a method for manufacturing a template for NIL, wherein a second template is obtained by a correction step for performing the above-described template defect correction method, and imprint transfer using the first template after the correction step. There is provided a template manufacturing method comprising a second template manufacturing step to be manufactured.

  In the present invention, a defect-free first template can be obtained by performing the above-described template defect correction method, and a defect-free second template can be obtained by producing a second template using the first template. It is possible to obtain.

  In the present invention, the black defect portion of the first template is inspected by the white defect portion of the inspection template, so that even if the first template has a minute black defect portion that is difficult to detect, it is detected with high sensitivity. There is an effect that it is possible.

It is a flowchart which shows an example of the defect correction method of the template of this invention. It is process drawing which shows an example of the preparation process of the template for a test | inspection in this invention. It is process drawing which shows the other example of the preparation process of the template for a test | inspection in this invention. It is process drawing which shows the other example of the preparation process of the template for a test | inspection in this invention. It is process drawing which shows the other example of the preparation process of the template for a test | inspection in this invention. It is process drawing which shows the other example of the preparation process of the template for a test | inspection in this invention. It is process drawing which shows the other example of the preparation process of the template for a test | inspection in this invention. It is process drawing which shows the other example of the preparation process of the template for a test | inspection in this invention. It is a flowchart which shows the other example of the defect correction method of the template of this invention. It is a flowchart which shows an example of the inspection method of the template of this invention. It is a flowchart which shows an example of the manufacturing method of the template of this invention. 2 is a SEM photograph of a first template and an inspection template of Example 1. It is a SEM photograph of the 1st template of Example 2, and an inspection template. It is a SEM photograph of the 1st template of Example 3, and an inspection template. It is a SEM photograph of the 1st template of Example 4, and an inspection template. 10 is a SEM photograph of a first template and an inspection template of Example 5.

  Hereinafter, the defect correction method, inspection method, and manufacturing method of the NIL template of the present invention will be described in detail.

A. Template defect correction method A template manufacturing method according to the present invention is a template defect correction method for NIL, and includes a first template preparation step for preparing a first template, and imprint transfer using the first template. By the inspection template preparation step for preparing the inspection template, the inspection template inspection step for inspecting the white defect portion of the inspection template, and when the white defect portion is detected in the inspection template, A first template defect confirmation step for confirming a black defect portion of the first template to which a white defect portion is transferred, and a first correction for correcting the black defect portion when the black defect portion is detected in the first template. And a template defect correcting step.

The template defect correction method of the present invention will be described with reference to the drawings.
FIG. 1 is a flowchart showing an example of a template defect correction method of the present invention. 2 (a)-(b), FIGS. 3 (a)-(e) and FIGS. 4 (a)-(d), and FIGS. 5 (a)-(e) and FIGS. 6 (a)-(d). These are process drawings which show an example of the test template preparation process in this invention. 3A is a cross-sectional view taken along line AA in FIG. 2A, FIG. 4D is a cross-sectional view taken along line AA in FIG. 2B, and FIG. ) Of FIG. 6B is a cross-sectional view taken along the line BB of FIG.
First, as shown in FIG. 1, a first template preparation step S1 is performed. For example, as shown in FIGS. 2 (a), 3 (a), and 5 (a), a first template that has a concavo-convex pattern 4 composed of convex portions 2 and concave portions 3 on the surface and is made of a transparent substrate. Prepare 1 In this example, the first template 1 has a black defect portion 5. In addition, a black defect part means defects, such as a surplus pattern and a foreign material.

  Next, as shown in FIG. 1, a test template manufacturing step S2 is performed. For example, as shown in FIG. 2B, the inspection template 10 having the white defect portion 15 to which the black defect portion 5 is transferred is produced by imprint transfer using the first template 1. Specifically, first, as shown in FIGS. 3B and 5B, a laminate in which a hard mask layer 16 and a resin layer 17 are laminated on an inspection substrate 10A is prepared. Next, as shown in FIGS. 3C to 3D and FIGS. 5C to 5D, the first template 1 is adhered to the resin layer 17, the resin layer 17 is cured, and the first template 1 is attached. It peels and the uneven | corrugated pattern 24 which consists of the convex part 22 and the recessed part 23 is transcribe | transferred to the resin layer 17. FIG. Next, as shown in FIGS. 3D to 3E and FIGS. 5D to 5E, the recesses 23 of the uneven pattern 24 of the resin layer 17 are etched until the hard mask layer 16 is exposed. Next, as shown in FIGS. 3E to 4A and FIGS. 5E to 6A, the exposed portion of the hard mask layer 16 is exposed to the inspection substrate 10A using the resin layer 17 as a mask. Etch until exposed. Subsequently, after removing the resin layer 17 as shown in FIGS. 4 (b) and 6 (b), as shown in FIGS. 4 (b) to (c) and FIGS. 6 (b) to (c), Using the hard mask layer 16 as a mask, the exposed portion of the inspection substrate 10A is etched. Thereafter, as shown in FIGS. 4D and 6D, the hard mask layer 16 is removed. Thereby, as shown in FIG. 4D and FIG. 6D, the inspection template 10 having the concave / convex pattern 14 including the convex portions 12 and the concave portions 13 on the surface and configured of the transparent substrate is obtained.

Next, as shown in FIG. 1, an inspection template inspection step S3 is performed. For example, the inspection template is inspected using an electron beam or light.
Next, as shown in FIG. 1, when a white defect portion is detected in the inspection template, a first template defect confirmation step S4 is performed. Specifically, the black defect portion of the first template to which the white defect portion of the inspection template is transferred is confirmed using an electron beam or light. For example, in FIGS. 2 (b), 4 (d) and 6 (d), the inspection template 10 has a white defect portion 15, which is shown in FIGS. 2 (a) and 5 (a). As described above, the first template 1 has the black defect portion 5 to which the white defect portion 15 of the inspection template 10 is transferred.
Next, as shown in FIG. 1, when a black defect portion is detected in the first template, a first template defect correction step S5 is performed. Specifically, the black defect portion of the first template is corrected by etching.

  In the present invention, in the inspection template manufacturing step, for example, as shown in FIGS. 3C to 3D and FIGS. 5C to 5D, the resin layer 17 contracts when it is cured, or FIG. As shown in d) to (e) and FIGS. 5D to 5E, when the resin layer 17 is etched, the side surfaces of the convex portions 22 of the concavo-convex pattern 24 of the resin layer 17 are etched to have a tapered shape. Or when the hard mask layer 16 is etched as shown in FIGS. 4A and 6A, the side surfaces of the hard mask layer 16 are etched to have a tapered shape. As a result, the hard mask layer 16 is over-etched as shown in FIGS. 4 (a) and 6 (a). As a result, as shown in FIGS. 4 (d) and 6 (d), the size of the concave portion 13 of the concave / convex pattern 14 of the inspection template 10 is the plane of the convex portion 2 of the concave / convex pattern 4 of the first template 1. It becomes larger than the size of the view (broken line in the figure). When the black defect portion 5 of the first template 1 is transferred, the white defect portion 15 of the inspection template 10 is obtained, but the size of the white defect portion 15 of the inspection template 10 in plan view is similarly black. It becomes larger than the size of the defect portion 5 in plan view. In this example, as shown in FIGS. 2A and 2B, the length d2 of the white defect portion 15 of the inspection template 10 in the longitudinal direction of the line pattern is equal to the black defect portion 5 of the first template 1. It is larger than the length d1. That is, the white defect portion 15 of the inspection template 10 is emphasized with respect to the black defect portion 5 of the first template 1.

  In the above example, the short defect black defect portion 5 of the first template 1 as shown in FIG. 2A is replaced by the open defect white defect portion 15 of the inspection template 10 as shown in FIG. 2B. Although the case of inspecting has been described, the present invention is not limited to this. For example, the black defect portion 5 of the edge defect of the first template 1 as shown in FIG. 7A can be inspected by the white defect portion 15 of the edge defect of the inspection template 10 as shown in FIG. 7B. . Similarly in this case, as shown in FIGS. 7A and 7B, the length d2 of the white defect portion 15 of the inspection template 10 in the longitudinal direction of the line pattern is equal to the black defect portion 5 of the first template 1. Is longer than the length d1. Thus, in the present invention, the white defect portion of the inspection template can be emphasized by producing the inspection template having the white defect portion to which the black defect portion of the first template is transferred.

  Therefore, in the present invention, the defect portion can be detected with high sensitivity by inspecting the black defect portion of the first template with the white defect portion of the inspection template. Therefore, even when the first template has a minute black defect portion, particularly when the first template has a minute black defect portion that is difficult to detect with an existing defect inspection apparatus, the defect portion can be detected with high sensitivity. .

  Further, in nanoimprint lithography, the concave / convex pattern of the template is transferred by being pressed against the transfer target. Therefore, if the template has a defective portion, the defective portion is transferred as it is. In photomasks and EUV masks, for example, because the pattern is reduced and exposed by a factor of 1/4, the influence of the defective portion is reduced, whereas in the NIL template, the concavo-convex pattern is transferred in full size in principle. There is a specific problem that the influence of the defective part appears directly. Therefore, inspection of the defective portion is particularly important. However, in the present invention, even a minute black defect portion that is difficult to detect as described above can be detected with high sensitivity.

  In addition, defect inspection includes optical inspection and electron beam inspection, and optical inspection has an advantage that the inspection time is extremely short as compared with electron beam inspection, but has a problem of low sensitivity. On the other hand, in the present invention, the black defect portion of the first template is inspected with the white defect portion of the inspection template so that the first template has a minute black defect portion that is difficult to detect by optical inspection. The defect portion can be detected with high sensitivity by optical inspection, and can be detected with high sensitivity comparable to that of electron beam inspection. As a result, high-speed and high-sensitivity inspection can be realized, and productivity can be greatly improved. Therefore, the present invention is particularly useful for optical inspection.

  Hereinafter, each step in the template defect correction method of the present invention will be described.

1. First template preparation step The first template is usually composed of a transparent substrate. Examples of the material constituting the transparent substrate include synthetic quartz, soda glass, fluorite, and calcium fluoride. Above all, it has a proven track record as a photomask substrate, has a stable quality, can be made into an integrated structure by forming an uneven pattern, and can form a fine uneven pattern with high precision. Are preferably used.
As the light transmittance of the transparent substrate, the light transmittance in the wavelength range of 300 nm to 450 nm is preferably 85% or more.
Moreover, although the thickness of a transparent substrate changes with materials, a use, etc., it is about 0.5 mm-10 mm, for example.

The first template has an uneven pattern on the surface. The shape of the concavo-convex pattern is not particularly limited, and examples thereof include line and space, dots, holes, isolated spaces, isolated lines, pillars, lenses, and steps.
In addition, the size of the concavo-convex pattern can be the same as that of a general NIL template.

  When the first template has a black defect portion, examples of the black defect portion include a short defect as shown in FIG. 2A, an edge black defect as shown in FIG. Is mentioned. The type of black defect varies depending on where the pattern occurs, black defects that are connected between line patterns are short defects, black defects that occur at the pattern edge are edge defects, and black defects that are isolated on the space Is called a pin dot defect (BS: also called a black spot). In the present invention, any black defect portion can be detected with high sensitivity by inspecting the black defect portion of the first template with the white defect portion of the inspection template.

  The first template can be produced in the same manner as a typical NIL template. For example, blanks in which a hard mask layer and a resist layer are sequentially laminated on a transparent substrate are prepared. Method of patterning a resist layer, etching the hard mask layer using the patterned resist layer as a mask to remove the resist layer, and etching the transparent substrate using the etched hard mask layer as a mask to remove the hard mask layer Is mentioned.

  In the present invention, the first template may be a template (master template) obtained by processing blanks, or a template (replica template) obtained by imprint transfer using the master template. It is also possible to use a template obtained by further transferring the replica template any number of times. Among these, the first template is preferably a master template. This is because a defect-free master template can be obtained by the template defect correction method of the present invention, and a defect-free replica template can be obtained using this defect-free master template.

2. Inspection Template Preparation Step In the inspection template preparation step of the present invention, an inspection template is prepared by imprint transfer using the first template.

The method for producing the inspection template may be an imprint method using the first template, and may be the same as a general method for producing a template for NIL. For example, the inspection template manufacturing step includes a lamination step of laminating a hard mask layer and a resin layer on an inspection substrate, the first template is brought into close contact with the resin layer, the resin layer is cured, and then the first A transfer step of peeling the template and forming the resin layer having a concavo-convex pattern on the surface, a first etching step of etching the concave portion of the concavo-convex pattern of the resin layer until the hard mask layer is exposed, and the hard A second etching step for etching the exposed portion of the mask layer until the inspection substrate is exposed, a third etching step for etching the exposed portion of the inspection substrate, and a hard mask layer removal for removing the hard mask layer Process.
Hereinafter, each process in the test template manufacturing process will be described.

(1) Lamination process In a lamination process, a hard mask layer and a resin layer are laminated on a substrate for inspection.

  An example of the inspection substrate is a transparent substrate. Note that the transparent substrate is the same as the first template, and thus the description thereof is omitted here.

Examples of the material used for the hard mask layer include metals such as Cr, Ta, Mo, and Ti, alloys containing these metals, and oxides and nitrides containing these metals.
The thickness of the hard mask layer is preferably in the range of 3 nm to 100 nm, for example, and more preferably in the range of 5 nm to 30 nm.
Examples of the method for forming the hard mask layer include vapor deposition.

As a material used for a resin layer, what is necessary is just a curable resin which can be hardened in the below-mentioned transfer process, for example, a photocurable resin is mentioned. Specific examples of the photocurable resin include PAK-01 (manufactured by Toagosei Co., Ltd.), NIP-K (manufactured by Zen Photonics), TSR-820 (manufactured by Teijin Seiki Co., Ltd.), and the like. PAK-01 (manufactured by Toagosei Co., Ltd.) is preferably used because it tends to cure and shrink.
The thickness of the resin layer can be set at, for example, about 10 nm to several hundred nm.
Examples of the method for forming the resin layer include a method for applying a curable resin composition on an inspection substrate. Examples of the application method include an ink jet method, a dropping method, and a spin coating method.

(2) Transfer process In the transfer process, the first template is brought into close contact with the resin layer, the resin layer is cured, and then the first template is peeled to form the resin layer having an uneven pattern on the surface. .

  As a method for curing the resin layer, a method of irradiating light is usually used. Examples of the light type include ultraviolet light, visible light, infrared light, and X-ray. The wavelength band of ultraviolet rays generally used is, for example, in the range of 300 nm to 400 nm. In addition, the amount of light irradiation is not particularly limited as long as the curable resin is sufficiently cured.

  The uneven pattern of the resin layer is obtained by transferring the uneven pattern of the first template, and the shape and dimensions of the uneven pattern of the resin layer are the same as the uneven pattern of the first template.

  When the inspection template has a white defect part, examples of the white defect part include an open defect as shown in FIG. 2B, an edge white defect as shown in FIG. 7B, and a pinhole defect (not shown). Is mentioned. Note that the type of white defect differs depending on where the pattern is generated.The white defect that the line pattern is disconnected is an open defect, the white defect that occurs at the pattern edge is the edge white defect, and the white defect that is isolated on the line pattern is The defect is called a pinhole defect.

  The method for peeling the first template is not particularly limited, and is the same as the method used in general imprinting.

(3) 1st etching process At a 1st etching process, the recessed part of the uneven | corrugated pattern of the said resin layer is etched until the said hard mask layer is exposed. By etching the uneven pattern of the resin layer as a whole to reduce the thickness, the resin layer in the recess is removed, and the underlying hard mask layer is exposed. At this time, the resin layer of the convex part remains.
An example of the method for etching the resin layer is dry etching. Moreover, it is preferable that the etching method of a resin layer is a method which can selectively etch a resin layer among a resin layer and a hard mask layer. The type of gas used for dry etching is appropriately selected according to the material and thickness of the resin layer and the hard mask layer. For example, the resin layer can be etched with a gas such as oxygen, nitrogen, chlorine, or fluorine.

(4) Second Etching Step In the second etching step, the exposed portion of the hard mask layer is etched until the inspection substrate is exposed.
Examples of the etching method for the hard mask layer include dry etching. Moreover, it is preferable that the etching method of a hard mask layer is a method which can selectively etch a hard mask layer among a resin layer and a hard mask layer. The type of gas used for dry etching is appropriately selected according to the material and thickness of the resin layer and the hard mask layer. For example, a mixed gas of chlorine and oxygen can be used.

After the hard mask layer is etched, the resin layer is usually removed. The removal of the resin layer is preferably performed before the third etching step described later. If there is a resin layer when the exposed portion of the inspection substrate is etched in the third etching step, there is a possibility that the etching cannot be stably performed due to a scum (residue) or a residual film of the resin layer. Further, when proceeding from etching of the hard mask layer to etching of the inspection substrate, the dry etching chamber is generally changed. However, when this chamber is changed, there is a possibility that foreign matter may adhere to the inspection substrate. By removing the resin layer before etching the inspection substrate, the foreign matter can be removed at the same time.
Examples of the method for removing the resin layer include wet etching or dry etching. In wet etching, only the resin layer can be easily removed.

(5) Third Etching Step In the third etching step, the exposed portion of the inspection substrate is etched.
Examples of the etching method for the inspection substrate include dry etching. Moreover, it is preferable that the etching method of the inspection substrate is a method capable of selectively etching the inspection substrate out of the inspection substrate and the hard mask layer. The type of gas used for dry etching is appropriately selected according to the material and thickness of the inspection substrate and the hard mask layer. For example, CF ₄ , SF ₆ , CHF ₃ , and C ₄ F ₈ can be used, and oxygen and helium gas may be further mixed.

(6) Hard mask layer removing step In the hard mask layer removing step, the hard mask layer is removed.
Examples of the method for removing the hard mask layer include wet etching or dry etching. In wet etching, only the hard mask layer can be easily removed. In wet etching, for example, when the hard mask layer contains chromium, an aqueous solution containing ceric ammonium nitrate and perchloric acid can be used. In dry etching, for example, when the hard mask layer contains chromium, a mixed gas of chlorine and oxygen can be used.

(7) Defect emphasis process In this invention, it is preferable that the inspection template preparation process has a defect emphasis process which emphasizes the said white defect part. This is because it becomes easier to detect the black defect portion of the first template to which the white defect portion of the inspection template is transferred.

  Here, “emphasizing the white defect portion” means that the white defect portion of the inspection template to which the black defect portion is transferred is compared with the size of the black defect portion of the first template in plan view. To increase the size.

The size in plan view of the black defect portion and the white defect portion to be compared may be, for example, a length or a width. Specifically, when the concavo-convex pattern is a line and space pattern, the lengths of the black defect portion and the white defect portion in the longitudinal direction of the line pattern can be mentioned.
More specifically, when the first template has a line and space pattern, the black defect portion 5 of the short defect of the first template 1 as shown in FIG. 2A is shown in FIG. When inspecting with the white defect portion 15 of the open defect of the inspection template 10 as described above, the length d2 of the white defect portion 15 of the inspection template 10 in the longitudinal direction of the line pattern is set to the black defect portion of the first template 1. By making it larger than the length d1 of 5, the white defect portion can be emphasized.
Further, when the first template has a line and space pattern, the black defect portion 5 of the edge defect of the first template 1 as shown in FIG. 7A is for inspection as shown in FIG. 7B. When inspecting by the white defect portion 15 of the edge defect of the template 10, the length d2 of the white defect portion 15 of the inspection template 10 in the longitudinal direction of the line pattern is set to the length of the black defect portion 5 of the first template 1. By making it larger than d1, the white defect portion can be emphasized.

In the defect emphasizing step, the size of the white defect portion of the inspection template to which the black defect portion of the first template is transferred is increased with respect to the size of the black defect portion of the first template. For example, a method for increasing the etching time of the resin layer in the first etching step, and a method for increasing the etching time of the hard mask layer in the second etching step. And a method of irradiating the resin layer with an electron beam or ultraviolet rays during the transfer step or after the transfer step.
Hereinafter, the method of extending the etching time and the method of irradiating the resin layer with an electron beam or ultraviolet light will be described separately.

(A) Etching time In the method of increasing the etching time of the resin layer in the first etching step, for example, when the resin layer 17 is etched as shown in FIGS. The size of the plan view of the portion can be made larger than the size of the black defect portion 5 of the first template 1 in the plan view. As a result, as shown in FIG. 6A, when the hard mask layer 16 is etched, the hard mask layer 16 is over-etched, and the size of the opening of the hard mask layer 16 in plan view is reduced to black of the first template 1. It can be made larger than the size of the defective portion 5 in plan view. As a result, as shown in FIG. 6D, the size of the white defect portion 15 of the inspection template 10 in plan view is larger than the size of the black defect portion 5 of the first template 1 in plan view (broken line in the figure). Can also be increased.

  Further, in the method of extending the etching time of the hard mask layer in the second etching step, the hard mask layer 16 is over-etched when the hard mask layer 16 is etched, for example, as shown in FIG. The size of the opening of the mask layer 16 in plan view can be made larger than the size of the black defect portion 5 of the first template 1 in plan view. As a result, as shown in FIG. 6D, the size of the white defect portion 15 of the inspection template 10 in plan view is larger than the size of the black defect portion 5 of the first template 1 in plan view (broken line in the figure). Can also be increased.

In the method of lengthening the etching time in the first etching step, specifically, the etching in the first etching step is performed more than when the second template is produced by imprint transfer using the first template. It is preferable to lengthen the time.
As such a method, for example, a method of increasing the thickness of the remaining film portion of the concavo-convex pattern of the resin layer can be mentioned, and specifically, the first printing is performed by imprinting using the first template. It is preferable to increase the thickness of the remaining film portion of the concavo-convex pattern of the resin layer, rather than when producing the two templates. Since the thickness of the remaining film portion of the uneven pattern of the resin layer is thick, the etching time of the resin layer can be extended. The thicker the remaining film portion of the concavo-convex pattern of the resin layer is, the longer the etching time of the resin layer becomes, and when etching the resin layer, the size of the opening of the resin layer in plan view is determined as the black defect of the first template. It is thought that it can be made larger than the size of the part in plan view.

Here, in nanoimprint lithography, the thickness of the remaining film portion of the transferred concavo-convex pattern is called RLT (Residual Layer Thickness). In the present invention, the thickness of the remaining film portion of the concavo-convex pattern of the resin layer refers to the thickness T of the concave portion 23 of the concavo-convex pattern 24 of the resin layer 17 as illustrated in FIG.
Usually, when the second template is produced by imprint transfer using the first template, it is desirable that the RLT is as thin as possible. Depending on the size and material of the concavo-convex pattern, for example, the height of the resin layer Is about 10 nm, RLT is about 10 nm.
On the other hand, in the present invention, it is preferable to increase the thickness of the remaining film portion of the concavo-convex pattern of the resin layer, compared to the case where the second template is produced by imprint transfer using the first template. Specifically, the thickness of the remaining film portion of the concavo-convex pattern of the resin layer is preferably in the range of 0.15 to 0.7, where the height of the convex portion of the concavo-convex pattern of the resin layer is 1. . More specifically, the thickness of the remaining film portion of the concavo-convex pattern of the resin layer is within the range of 6.8 nm to 70 nm when the height of the convex portion of the concavo-convex pattern of the resin layer is within the range of 45 nm to 100 nm. Can be set. If the thickness of the remaining film portion of the concavo-convex pattern of the resin layer is too thin, the etching time of the resin layer cannot be lengthened, and it becomes difficult to sufficiently emphasize the white defect portion. On the other hand, if the thickness of the remaining film portion of the concavo-convex pattern of the resin layer is too thick, when the resin layer is etched, the convex portion of the concavo-convex pattern of the resin layer is the cross-section of the resin layer 17 illustrated in FIG. As described above, since the etching proceeds from two directions, that is, etching from the upper direction and etching from the lower direction but less from the upper direction, the height is reduced, and the exposed portion of the hard mask layer is removed in the second etching step. When etching is performed, it may not function as a mask. In addition, if the thickness of the remaining film portion of the uneven pattern of the resin layer is too thick, the size of the opening of the resin layer when viewed in plan is the plan view of the convex portion of the uneven pattern of the first template. In some cases, it becomes difficult to form a concavo-convex pattern on the inspection substrate, or the etching time of the resin layer becomes too long, resulting in poor production efficiency.
In the present invention, the height of the convex portion of the concavo-convex pattern of the resin layer is indicated by a height H as illustrated in FIG.

  For example, when the etching selectivity of the resin layer and the hard mask layer is high in the first etching step, the etching time of the resin layer may be simply increased.

On the other hand, in the method of extending the etching time in the second etching step, specifically, in the second etching step, compared to the case where the second template is produced by imprint transfer using the first template. It is preferable to increase the etching time.
As such a method, for example, a method of increasing the thickness of the hard mask layer can be mentioned, and specifically, when a second template is produced by imprint transfer using the first template. It is preferable to increase the thickness of the hard mask layer. Since the hard mask layer is thick, the etching time of the hard mask layer can be extended. The thicker the hard mask layer, the longer the etching time of the hard mask layer. When etching the hard mask layer, the size of the opening of the hard mask layer in plan view is the plane of the black defect portion of the first template. It is thought that it can be larger than the size of vision.

Usually, when the second template is produced by imprint transfer using the first template, it is desirable that the thickness of the hard mask layer is as thin as possible because the uneven pattern is fine. For example, the thickness of the hard mask layer is about 3 nm to 10 nm.
On the other hand, in the present invention, it is preferable to make the hard mask layer thicker than when the second template is produced by imprint transfer using the first template. Specifically, the thickness of the hard mask layer is preferably in the range of 5 nm to 30 nm. If the thickness of the hard mask layer is too thin, it will be difficult to increase the etching time of the hard mask layer. If the thickness of the hard mask layer is too thick, the size of the opening of the hard mask layer when viewed from the top when the hard mask layer is etched is larger than the size of the projection of the convex and concave pattern of the first template. In some cases, it becomes too large and it becomes difficult to form a concavo-convex pattern on the inspection substrate, or the etching time of the hard mask layer becomes too long, and the manufacturing efficiency may deteriorate.

  For example, when the etching selectivity of the resin layer and the hard mask layer is high in the second etching step, the etching time of the hard mask layer may be simply increased.

  The above-described method for increasing the etching time may be applied singly or in combination.

(B) Irradiation of electron beam or ultraviolet ray In the method of irradiating the resin layer with an electron beam or ultraviolet ray during or after the transfer step, for example, electrons are applied to the resin layer 17 as shown in FIGS. It can be shrunk by irradiation with rays or ultraviolet rays (not shown). Thereby, as shown in FIG. 8C, the size of the opening of the resin layer 17 in plan view is made larger than the size of the black defect portion 5 of the first template 1 in plan view in the first etching step. As shown in FIG. 8D, the size of the opening of the hard mask layer 16 in plan view is made larger than the size of the black defect portion 5 of the first template 1 in plan view in the second etching step. be able to. Thus, as shown in FIG. 8G, the size of the white defect portion 15 of the inspection template 10 in plan view is larger than the size of the black defect portion 5 of the first template 1 in plan view (broken line in the figure). Can also be increased.
The steps shown in FIGS. 8A to 8G are the same as those shown in FIGS. 5C to 5E and FIGS. 6A to 6D.

  When the resin layer is irradiated with an electron beam, for example, as shown in FIG. 8B, the electron beam can be irradiated after the first template 1 is peeled from the resin layer 17, that is, after the transfer step. The resin layer can be contracted by irradiating the resin layer cured in the transfer step with an electron beam.

  On the other hand, when the resin layer is irradiated with ultraviolet rays, for example, as shown in FIG. 8A, the first template 1 is brought into close contact with the resin layer 17 to cure the resin layer 17, that is, during the transfer process. Alternatively, as shown in FIG. 8B, ultraviolet light may be irradiated after the first template 1 is peeled from the resin layer 17, that is, after the transfer step. In the case where an ultraviolet curable resin is used for the resin layer, the first template is brought into close contact with the resin layer, and the resin layer can be simultaneously contracted when cured by ultraviolet rays. Further, the resin layer can be contracted by irradiating the resin layer cured in the transfer step with ultraviolet rays.

The wavelength band of ultraviolet rays generally used is, for example, in the range of 300 nm to 400 nm.
The irradiation amount of ultraviolet rays or electron beams is not particularly limited as long as it is an amount capable of shrinking the curable resin.

(C) Others The method for emphasizing the white defect portion described above may be applied alone or in combination.

3. Inspection Template Inspection Process In the inspection template inspection process of the present invention, the white defect portion of the inspection template is inspected.

Examples of the inspection method of the white defect portion of the inspection template include a method of inspecting the white defect portion by irradiating a charged beam or light.
The charged beam is not particularly limited as long as the white defect portion can be inspected, and examples thereof include an electron beam and an ion beam. The electron beam has an advantage that the beam can be narrowed down to several nanometers and has high sensitivity, and the charged particle mass is smaller than that of the ion beam, so that the damage to the inspection template is small. In the case of an electron beam, it can be examined by an electron microscope such as a scanning electron microscope (SEM).
On the other hand, the light is not particularly limited as long as the white defect portion can be inspected, and examples thereof include light used for curing the resin layer. Specifically, ultraviolet light, visible light, infrared light, X-rays can be mentioned. More specifically, light having a short wavelength, for example, 193 nm light can be used because of high sensitivity.
Among these, optical inspection is preferable. Although the electron beam inspection has high sensitivity, the inspection speed is very slow, and a great deal of time is spent on the inspection. On the other hand, in the optical inspection, although the sensitivity is low, the inspection speed is fast and the throughput can be improved. In the present invention, since the white defect portion can be detected with high sensitivity, optical inspection can also be used, and high-speed and high-sensitivity inspection can be realized.

  The inspection of the white defect portion of the inspection template may be performed after the hard mask layer removing step in the defect template manufacturing step, may be performed after the third etching step, or performed after the second etching step. It may be selected appropriately according to the inspection method. For example, in the case of optical inspection, since the gradation difference becomes large, it is preferable to perform optical inspection with the hard mask layer remaining after the third etching step. In the case of optical inspection, if the hard mask layer is relatively thick, the optical inspection can be performed after the second etching step. On the other hand, in the case of electron beam inspection, the electron beam inspection may be performed with the hard mask layer remaining, or may be performed with the hard mask layer removed.

  When inspecting a white defect portion of an inspection template, the entire inspection template is usually inspected.

4). First Template Defect Confirmation Step In the first template defect confirmation step in the present invention, when the white defect portion is detected in the inspection template, the black defect portion of the first template to which the white defect portion is transferred is confirmed. To do.

  Examples of the method for confirming the black defect portion of the first template include a method of confirming the black defect portion by irradiating a charged beam or light. Since the inspection using the charged beam and light is the same as the above-described inspection template inspection step, description thereof is omitted here.

In the first template defect confirmation step, a black defect portion corresponding to the white defect portion detected in the inspection template inspection step is confirmed.
When checking the black defect portion of the first template, only the vicinity of the black defect portion may be inspected, or the entire first template may be inspected, but usually only the vicinity of the black defect portion is inspected. That's fine.

  The white defect portion of the inspection template may be generated during the inspection template manufacturing process. Therefore, there may be a case where the black defect portion corresponding to the white defect portion of the inspection template does not exist in the first template. In this case, even if a white defect portion is detected in the inspection template inspection process, it is not necessary to take any special measures in the first template defect correction process described later.

5. First Template Defect Correction Step In the first template defect correction step of the present invention, the black defect portion is corrected when the black defect portion is detected in the first template.

  As a method for correcting the black defect portion, there is a method of etching the black defect portion by irradiating a charged beam while supplying an assist gas to the black defect portion.

  The charged beam is not particularly limited as long as only the black defect portion can be locally etched, and examples thereof include an electron beam and an ion beam. Among these, an electron beam is preferable. This is because the electron beam can be narrowed down to several nanometers and has high correction accuracy, and since the mass of charged particles is smaller than that of the ion beam, damage to the first template is small.

The assist gas is not particularly limited as long as it is a gas capable of etching the black defect portion. The assist gas may be a single component gas or a mixed gas containing plural kinds of gases. For example, when an electron beam is used, the assist gas includes xenon fluoride (XeF ₂ ). On the other hand, when an ion beam is used, examples of the assist gas include xenon fluoride (XeF ₂ ) and iodine (I ₂ ).

  Examples of the supply method of the assist gas include a method of spraying the assist gas locally on the black defect portion, a method of arranging the first template in the assist gas atmosphere, and the like.

6). Other Steps In the present invention, as illustrated in FIG. 9, a first template inspection step S11 for inspecting a defective portion of the first template may be performed before the inspection template manufacturing step S2. After 1 template inspection process S11, you may perform 1st template defect correction process S12 before the test template preparation which corrects the defect part of the said 1st template. When performing the first template inspection step S11 and the first template defect correction step S12 before the preparation of the inspection template, inspection and correction are performed on the defective portion of the first template that can be detected without using the inspection template. It can be carried out. On the other hand, when the first template inspection step S11 and the first template defect correction step S12 before the preparation of the inspection template are not performed, the inspection template inspection step S3, the first template defect confirmation step S4, and the first template defect correction step are performed. By S5, the defect portion of the first template can be inspected and corrected. Although not shown, when the first template inspection step S11 is performed, the defect portion detected in the first template inspection step S11 is not performed without performing the first template defect correction step S12 before the preparation of the inspection template. You may correct in 1st template defect correction process S5 after 1 template defect confirmation process S4.

(1) First template inspection step In the first template inspection step, a defective portion of the first template is inspected.
Examples of the method for inspecting the defect portion of the first template include a method for inspecting the defect portion by irradiating a charged beam or light. Since the inspection using the charged beam and light is the same as the above-described inspection template inspection step, description thereof is omitted here.
When inspecting the defective portion of the first template, the entire first template is usually inspected.

(2) First Template Defect Correction Process Before Inspection Template Preparation In the first template defect correction process before inspection template preparation, the black defect portion may be corrected or the white defect portion may be corrected.
The method for correcting the black defect portion is the same as that in the first template defect correction step described above, and a description thereof will be omitted here.

Further, as a method for correcting the white defect portion, there is a method of depositing a correction film by irradiating a charged beam while supplying a deposition gas to the white defect portion.
The charged beam is not particularly limited as long as the correction film can be locally deposited only on the white defect portion, and can be the same as that used for correction of the black defect portion.

As the deposition gas, for example, a gas generally used when a CVD method using a charged beam is applied can be used. In addition, the deposition gas can be deposited with a correction film having a hardness that does not deform when the inspection template is manufactured using the first template, and the resin layer used for manufacturing the inspection template. It is also required not to react with etc. For example, when using an electron beam, examples of the deposition gas include phenanthrene, tungsten carbonyl (W (CO) ₆ ), tungsten fluoride (WF ₆ ), and tetraethoxysilane (TEOS). On the other hand, when an ion beam is used, examples of the deposition gas include phenanthrene, tungsten carbonyl (W (CO) ₆ ), and tetraethoxysilane (TEOS).

  Examples of the deposition gas supply method include a method of locally spraying the deposition gas on the white defect portion, a method of arranging the first template in the atmosphere of the deposition gas, and the like.

B. Template inspection method A template inspection method according to the present invention is a template inspection method for NIL, and includes a first template preparation step of preparing a first template, and imprint transfer using the first template. An inspection template manufacturing step for manufacturing an inspection template; and an inspection template inspection step for inspecting a white defect portion of the inspection template. A black defect portion of the first template is replaced with a white portion of the inspection template. A template inspection method for inspecting with a defect portion, wherein the inspection template manufacturing step includes a defect emphasis step for emphasizing the white defect portion.

FIG. 10 is a flowchart showing an example of the template inspection method of the present invention. 2 (a)-(b), FIGS. 3 (a)-(e) and FIGS. 4 (a)-(d), and FIGS. 5 (a)-(e) and FIGS. 6 (a)-(d). These are process drawings which show an example of the test template preparation process in this invention. 2 (a)-(b), FIG. 3 (a)-(e), FIG. 4 (a)-(d), and FIG. 5 (a)-(e) and FIG. 6 (a)-( Since d) is described in the above section “A. Template defect correction method”, description thereof is omitted here.
In the template inspection method of the present invention, as shown in FIG. 10, the first template preparation step S1, the inspection template preparation step S21, and the inspection template inspection step S3 are performed in this order. The inspection template manufacturing step S21 includes a defect emphasizing step for emphasizing the white defect portion, and as described in the above section “A. Template defect correction method”, the plan view of the black defect portion of the first template. The size of the white defect portion of the inspection template in plan view can be increased with respect to the size of.

  In the present invention, the first template is difficult to detect by inspecting the black defect portion of the first template with the white defect portion of the inspection template, as described in the section “A. Template Defect Correction Method” above. Even if it has a very small black defect portion, it can be detected with high sensitivity.

  Each process in the template inspection method is the same as each process in the template defect correction method described above, and a description thereof is omitted here.

C. Template Manufacturing Method The template manufacturing method of the present invention has two embodiments. In the following, each embodiment will be described separately.

1. First Embodiment A template manufacturing method according to the present embodiment is a method for manufacturing a template for NIL, and includes a correcting step for performing the above-described template defect correcting method. That is, the template manufacturing method of this embodiment is a method of manufacturing the first template using the above-described template defect correction method.

  In the present invention, the first template is difficult to detect by inspecting the black defect portion of the first template with the white defect portion of the inspection template, as described in the section “A. Template Defect Correction Method” above. Even if it has a very small black defect portion, it can be detected with high sensitivity. Therefore, it is possible to obtain the first template having no defect.

The correction step is a step of performing the above-described template defect correction method. The above-described template defect correction method has been described in detail in the above section “A. Template defect correction method”, and thus the description thereof is omitted here.
In addition, the first template is manufactured before the correction process, but the first template manufacturing method is described in the above section “A. Template defect correcting method”, and thus the description thereof is omitted here.

2. Second Embodiment A template manufacturing method according to the present embodiment is a method for manufacturing a template for NIL, and includes a correction step for performing the above-described template defect correction method, and an in-process using the first template after the correction step. And a second template production step of producing a second template by transfer by printing. That is, the template manufacturing method of this embodiment is a method of manufacturing a first template using the above-described template defect correction method, and manufacturing a second template using the first template.

FIG. 11 is a flowchart showing an example of a template manufacturing method according to the present invention. The first template preparation step S1 to the first template defect correction step S5 are the same as the above-mentioned “A. Template defect correction method”.
After the first template defect correcting step S5, a second template manufacturing step S6 and a second template inspection step S7 are sequentially performed.

  In the present invention, the first template is difficult to detect by inspecting the black defect portion of the first template with the white defect portion of the inspection template, as described in the section “A. Template Defect Correction Method” above. Even if it has a very small black defect portion, it can be detected with high sensitivity. Therefore, the first template having no defect can be obtained. Thereby, it is possible to obtain the 2nd template without a defect.

  Hereinafter, each process in the manufacturing method of a template is demonstrated.

(1) Correction Step The correction step in the present embodiment is a step of performing the above-described template defect correction method. The above-described template defect correction method has been described in detail in the above section “A. Template defect correction method”, and thus the description thereof is omitted here.
In addition, the first template is manufactured before the correction process, but the first template manufacturing method is described in the above section “A. Template defect correcting method”, and thus the description thereof is omitted here.

(2) Second template production step In the second template production step, a second template is produced by imprint transfer using the first template after the correction step.
The second template may be manufactured by an imprint method using the first template, and may be the same as a general NIL template manufacturing method. For example, the second template manufacturing method includes a step of laminating a hard mask layer and a resin layer on a transparent substrate, the first template is brought into close contact with the resin layer, the resin layer is cured, and then the first template is formed. Peeling the template and forming the resin layer having a concavo-convex pattern on the surface; etching the concave portions of the concavo-convex pattern of the resin layer until the hard mask layer is exposed; and an exposed portion of the hard mask layer Can be a method having a step of etching until the transparent substrate is exposed, a step of etching an exposed portion of the transparent substrate, and a step of removing the hard mask layer.

(3) Second Template Inspection Step After the second template production step, a second template inspection step for inspecting the second template is usually performed.
Examples of the method for inspecting the second template include a method for inspecting by irradiating a charged beam or light. Since the inspection using the charged beam and light is the same as the above-described inspection template inspection step, description thereof is omitted here.
When inspecting the second template, the entire second template is usually inspected.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The following examples illustrate the present invention in more detail.

[Example 1]
(Production of the first template)
First, blanks were prepared in which a Cr oxide film having a thickness of 5 nm was formed as a hard mask layer on a quartz substrate having a size of 152 mm × 152 mm and a thickness of 0.25 inch. Next, an electron beam resist film was formed on the hard mask layer, and electron beam drawing and development were performed. Thereby, a resist pattern corresponding to the concavo-convex pattern was formed. Next, dry etching of the exposed portion of the Cr oxide film was performed with a mixed gas of chlorine and oxygen to expose the quartz substrate. Thereafter, the resist pattern was removed. Next, dry etching of the exposed portion of the quartz substrate was performed with fluorine gas. Thereafter, the hard mask layer was removed by wet etching to produce a first template.
FIG. 12A shows an SEM photograph (magnified 30,000 times) of the first template. The uneven | corrugated pattern of the 1st template was a line and space, the depth of the recessed part was 60 nm, and the width | variety of a recessed part and a convex part was 30 nm. Further, the first template had a black defect portion 5 having a short defect, and the length d1 of the black defect portion 5 in the longitudinal direction of the line pattern was 8 nm. In the SEM photograph, the white part is a convex part and the black part is a concave part.

(Preparation of inspection template)
An inspection template was produced using the first template. At this time, the thickness (RLT) of the remaining film portion of the uneven pattern of the resin layer was made thicker than when the second template was produced by imprint transfer using the first template.
First, blanks were prepared in which a Cr oxide film having a thickness of 5 nm was formed as a hard mask layer on a quartz substrate having a size of 152 mm × 152 mm and a thickness of 0.25 inch. Next, a resin layer that is a photocurable resin film having a thickness of 70 nm was formed on the hard mask layer, and the first template was adhered to the resin layer. The height of the convex portion of the concave / convex pattern of the resin layer when the first template was adhered to the resin layer was 50 nm, and the thickness (RLT) of the remaining film portion of the concave / convex pattern was 30 nm. Subsequently, the resin layer was irradiated with UV light and cured, and then the first template was peeled off to form a resin layer having an uneven pattern on the surface. The height of the convex part of the concave-convex pattern of the resin layer after peeling off the first template was 45 nm, and the thickness (RLT) of the remaining film part of the concave-convex pattern was 30 nm.
Next, the concave portions of the concavo-convex pattern of the resin layer were etched with O ₂ gas until the hard mask layer was exposed. The height of the convex portion of the resin layer after etching of the concave portion of the resin layer was 45 nm.
Next, the exposed portion of the hard mask layer was etched with a mixed gas of Cl ₂ and O ₂ until the quartz substrate was exposed. The height of the convex portion of the resin layer after etching the hard mask layer was 25 nm. Thereafter, the resin layer was removed with sulfuric acid / hydrogen peroxide and ammonia / hydrogen peroxide.
Next, the exposed portion of the quartz substrate was etched with a mixed gas of CF ₄ , O ₂ , and He. At that time, the thickness of the Cr oxide film was 3 nm. Further, the digging amount of the quartz substrate was 50 nm. Thereafter, the hard mask layer was removed with ceric ammonium nitrate solution. As a result, a desired inspection template was produced.

  FIG. 12B shows an SEM photograph (magnified 30,000 times) of the inspection template. The inspection template has a white defect portion 15 of an open defect, and the length d2 of the white defect portion 15 in the longitudinal direction of the line pattern is 26 nm.

[Example 2]
(Production of the first template)
A first template was produced in the same manner as in Example 1.
FIG. 13A shows an SEM photograph (magnified 30,000 times) of the first template. The uneven | corrugated pattern of the 1st template was a line and space, the depth of the recessed part was 60 nm, and the width | variety of a recessed part and a convex part was 30 nm. Further, the first template had a black defect portion 5 having a short defect, and the length d1 of the black defect portion 5 in the longitudinal direction of the line pattern was 10 nm.

(Preparation of inspection template)
An inspection template was produced using the first template. At this time, the thickness of the hard mask layer was made thicker than when the second template was produced by imprint transfer using the first template.
First, blanks were prepared in which a Cr oxide film having a thickness of 10 nm was formed as a hard mask layer on a quartz substrate having a size of 152 mm × 152 mm and a thickness of 0.25 inch. Next, a resin layer which is a photocurable resin film having a thickness of 50 nm was formed on the hard mask layer, and the first template was adhered to the resin layer. The height of the convex portion of the concave / convex pattern of the resin layer when the first template was adhered to the resin layer was 50 nm, and the thickness (RLT) of the remaining film portion of the concave / convex pattern was 10 nm. Subsequently, the resin layer was irradiated with UV light and cured, and then the first template was peeled off to form a resin layer having an uneven pattern on the surface. The height of the convex part of the concave-convex pattern of the resin layer after peeling off the first template was 45 nm, and the thickness (RLT) of the remaining film part of the concave-convex pattern was 10 nm.
Next, the concave portions of the concavo-convex pattern of the resin layer were etched with O ₂ gas until the hard mask layer was exposed. The height of the convex portion of the resin layer after etching of the concave portion of the resin layer was 45 nm.
Next, the exposed portion of the hard mask layer was etched with a mixed gas of Cl ₂ and O ₂ until the quartz substrate was exposed. The height of the convex portion of the resin layer after etching the hard mask layer was 15 nm. Thereafter, the resin layer was removed with sulfuric acid / hydrogen peroxide and ammonia / hydrogen peroxide.
Next, the exposed portion of the quartz substrate was etched with a mixed gas of CF ₄ , O ₂ , and He. At this time, the thickness of the Cr oxide film was 8 nm. Further, the digging amount of the quartz substrate was 50 nm. Thereafter, the hard mask layer was removed with ceric ammonium nitrate solution. As a result, a desired inspection template was produced.

  FIG. 13B shows an SEM photograph (30,000 times) of the inspection template. The inspection template has a white defect portion 15 of an open defect, and the length d2 of the white defect portion 15 in the longitudinal direction of the line pattern is 26 nm.

[Example 3]
(Production of the first template)
A first template was produced in the same manner as in Example 1.
FIG. 14A shows an SEM photograph (magnified 30,000 times) of the first template. The uneven | corrugated pattern of the 1st template was a line and space, the depth of the recessed part was 60 nm, and the width | variety of a recessed part and a convex part was 30 nm. Further, the first template had the black defect portion 5 of the edge defect, and the length d1 of the black defect portion 5 in the longitudinal direction of the line pattern was 14 nm.

(Preparation of inspection template)
An inspection template was produced using the first template in the same manner as in Example 1.
FIG. 14B shows an SEM photograph (magnified 30,000 times) of the inspection template. The inspection template has a white defect portion 15 of an edge defect, and the length d2 of the white defect portion 15 in the longitudinal direction of the line pattern is 28 nm.

[Example 4]
(Production of the first template)
A first template was produced in the same manner as in Example 1.
FIG. 15A shows an SEM photograph (magnified 30,000 times) of the first template. The uneven | corrugated pattern of the 1st template was a line and space, the depth of the recessed part was 60 nm, and the width | variety of a recessed part and a convex part was 30 nm. Further, the first template had the black defect portion 5 of the edge defect, and the length d1 of the black defect portion 5 in the longitudinal direction of the line pattern was 35 nm.

(Preparation of inspection template)
An inspection template was produced using the first template.
First, blanks were prepared in which a Cr oxide film having a thickness of 5 nm was formed as a hard mask layer on a quartz substrate having a size of 152 mm × 152 mm and a thickness of 0.25 inch. Next, a resin layer which is a photocurable resin film having a thickness of 50 nm was formed on the hard mask layer, and the first template was adhered to the resin layer. The height of the convex portion of the concave / convex pattern of the resin layer when the first template was adhered to the resin layer was 50 nm, and the thickness (RLT) of the remaining film portion of the concave / convex pattern was 10 nm. Subsequently, the resin layer was irradiated with UV light and cured, and then the first template was peeled off to form a resin layer having an uneven pattern on the surface. The height of the convex part of the concave-convex pattern of the resin layer after peeling off the first template was 45 nm, and the thickness (RLT) of the remaining film part of the concave-convex pattern was 10 nm.
Next, the concave portions of the concavo-convex pattern of the resin layer were etched with O ₂ gas until the hard mask layer was exposed. The height of the convex portion of the resin layer after etching of the concave portion of the resin layer was 45 nm.
Next, the exposed portion of the hard mask layer was etched with a mixed gas of Cl ₂ and O ₂ until the quartz substrate was exposed. The height of the convex portion of the resin layer after etching the hard mask layer was 25 nm. Thereafter, the resin layer was removed with sulfuric acid / hydrogen peroxide and ammonia / hydrogen peroxide.
Next, the exposed portion of the quartz substrate was etched with a mixed gas of CF ₄ , O ₂ , and He. At that time, the thickness of the Cr oxide film was 3 nm. Further, the digging amount of the quartz substrate was 50 nm. Thereafter, the hard mask layer was removed with ceric ammonium nitrate solution. As a result, an inspection template was produced.
FIG. 15B shows an SEM photograph (30,000 times) of the inspection template. The inspection template has a white defect portion 15 of an edge defect, and the length d2 of the white defect portion 15 in the longitudinal direction of the line pattern is 55 nm.

[Example 5]
(Production of the first template)
A first template was produced in the same manner as in Example 1.
FIG. 16A shows an SEM photograph (magnified 30,000 times) of the first template. The uneven | corrugated pattern of the 1st template was a line and space, the depth of the recessed part was 60 nm, and the width | variety of a recessed part and a convex part was 30 nm. Further, the first template had the black defect portion 5 of the edge defect, and the length d1 of the black defect portion 5 in the longitudinal direction of the line pattern was 14 nm.

(Preparation of inspection template)
An inspection template was produced using the first template in the same manner as in Example 4.
FIG. 16B shows an SEM photograph (30,000 times) of the inspection template. In the first template, the black defect portion of the edge defect is detected. However, the defect portion is enlarged in the inspection template by imprint transfer using the first template, and becomes the white defect portion 15 of the open defect, and is detected with high sensitivity. It became possible. Further, the length d2 of the white defect portion 15 in the longitudinal direction of the line pattern was 22 nm.

  From the above, it was confirmed that the white defect portion can be emphasized. Thereby, the black defect portion of the first template can be detected with high sensitivity by the white defect portion of the inspection template.

DESCRIPTION OF SYMBOLS 1 ... 1st template 2 ... Convex part 3 ... Concave part 4 ... Concave / convex pattern 5 ... Black defect part 10 ... Inspection template 10A ... Inspection substrate 12 ... Convex part 13 ... Concave part 14 ... Concave pattern 15 ... White defect part 16 ... Hard Mask layer 17 ... Resin layer 22 ... Convex part 23 ... Concave part 24 ... Concave and convex pattern

Claims (11)

A method for correcting defects in a template for nanoimprint lithography,
A first template preparation step of preparing a first template;
An inspection template preparation step of preparing an inspection template by imprint transfer using the first template;
An inspection template inspection step for inspecting a white defect portion of the inspection template;
A first template defect confirmation step of confirming a black defect portion of the first template that has transferred the white defect portion when the white defect portion is detected in the inspection template;
A template defect correction method comprising: a first template defect correction step of correcting the black defect portion when the black defect portion is detected in the first template.   The template defect correcting method according to claim 1, wherein the inspection template manufacturing step includes a defect emphasizing step of emphasizing the white defect portion. The inspection template manufacturing process includes:
A laminating step of laminating a hard mask layer and a resin layer on an inspection substrate;
After the first template is adhered to the resin layer and the resin layer is cured, the first template is peeled off, and a transfer step of forming the resin layer having a concavo-convex pattern on the surface;
A first etching step of etching the concave portion of the concave-convex pattern of the resin layer until the hard mask layer is exposed;
A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed;
A third etching step for etching an exposed portion of the inspection substrate;
A hard mask layer removing step for removing the hard mask layer, and in the defect emphasizing step, the first etching step is more effective than a case where the second template is formed by imprint transfer using the first template. The template defect correction method according to claim 2, wherein an etching time in the second etching step is increased.   In the defect emphasizing step, the thickness of the remaining film portion of the concavo-convex pattern of the resin layer is made thicker than when the second template is produced by imprint transfer using the first template. Item 4. A defect correction method for a template according to Item 3. The inspection template manufacturing process includes:
A laminating step of laminating a hard mask layer and a resin layer on an inspection substrate;
After the first template is adhered to the resin layer and the resin layer is cured, the first template is peeled off, and a transfer step of forming the resin layer having a concavo-convex pattern on the surface;
A first etching step of etching the concave portion of the concave-convex pattern of the resin layer until the hard mask layer is exposed;
A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed;
A third etching step for etching an exposed portion of the inspection substrate;
The hard mask layer removing step of removing the hard mask layer, wherein the defect emphasizing step irradiates the resin layer with an electron beam or an ultraviolet ray during the transfer step or after the transfer step. The template defect correction method according to 2. A method for inspecting a template for nanoimprint lithography,
A first template preparation step of preparing a first template;
An inspection template preparation step of preparing an inspection template by imprint transfer using the first template;
An inspection template inspection step for inspecting a white defect portion of the inspection template, and a template inspection method for inspecting a black defect portion of the first template by a white defect portion of the inspection template,
The template inspection method, wherein the inspection template manufacturing step includes a defect enhancement step of enhancing the white defect portion. The inspection template manufacturing process includes:
A laminating step of laminating a hard mask layer and a resin layer on an inspection substrate;
After the first template is adhered to the resin layer and the resin layer is cured, the first template is peeled off, and a transfer step of forming the resin layer having a concavo-convex pattern on the surface;
A first etching step of etching the concave portion of the concave-convex pattern of the resin layer until the hard mask layer is exposed;
A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed;
A third etching step for etching an exposed portion of the inspection substrate;
A hard mask layer removing step for removing the hard mask layer, and in the defect emphasizing step, the first etching step is more effective than a case where the second template is formed by imprint transfer using the first template. The template inspection method according to claim 6, wherein an etching time in the second etching step is increased.   In the defect emphasizing step, the remaining film portion of the concavo-convex pattern of the resin layer is made thicker than when the second template is produced by imprint transfer using the first template. Inspection method of the described template. The inspection template manufacturing process includes:
A laminating step of laminating a hard mask layer and a resin layer on an inspection substrate;
After the first template is adhered to the resin layer and the resin layer is cured, the first template is peeled off, and a transfer step of forming the resin layer having a concavo-convex pattern on the surface;
A first etching step of etching the concave portion of the concave-convex pattern of the resin layer until the hard mask layer is exposed;
A second etching step of etching the exposed portion of the hard mask layer until the inspection substrate is exposed;
A third etching step for etching an exposed portion of the inspection substrate;
The hard mask layer removing step of removing the hard mask layer, wherein the defect emphasizing step irradiates the resin layer with an electron beam or an ultraviolet ray during the transfer step or after the transfer step. 6. The template inspection method according to 6. A method for producing a template for nanoimprint lithography,
A template manufacturing method comprising a correcting step for performing the template defect correcting method according to any one of claims 1 to 5. A method for producing a template for nanoimprint lithography,
A correction step for performing the defect correction method for a template according to any one of claims 1 to 5,
And a second template production step of producing a second template by imprint transfer using the first template after the correction step.