JP2014194967A - Template for nano imprint and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a template for nano imprint capable of easily discriminating an alignment mark formed in the same step as the transfer pattern while using a side wall process for formation of the transfer pattern, and also to provide a method of manufacturing the same.SOLUTION: A discrimination pattern having a configuration in which a plurality of convex type structures are arrayed is formed in association with an alignment mark using a side wall process having the same step as formation of the transfer pattern.

Description

  The present invention relates to a template used in nanoimprint lithography for transferring a fine concavo-convex transfer pattern onto a resin formed on a transfer substrate, and a method for manufacturing the same.

2. Description of the Related Art Conventionally, in the manufacture of semiconductor devices, a photolithographic technique that uses a photomask to perform reduction (for example, 1/4 reduction) exposure has been used. In recent years, a phase shift mask has been used as a technique for further improving the resolution. A fine pattern such as a VLSI is manufactured by photolithography.
However, in order to cope with further miniaturization, the limitations of the above-described photolithography method have been pointed out due to the problem of the exposure wavelength and the problem of manufacturing cost. As a next generation lithography technique, a template (mold, stamper, Nanoimprint lithography (NIL) using a mold (also called a mold) has been proposed.

  In this nanoimprint lithography, a nanoimprint template (referred to as a template as appropriate) in which a fine uneven transfer pattern is formed on a surface is brought into contact with a resin formed on a substrate to be transferred such as a semiconductor wafer. The surface side shape is molded into a concavo-convex shape of the template transfer pattern, then released, and then the excess resin portion (residual film portion) is removed by dry etching or the like, so that the template on the resin on the substrate to be transferred This is a technique for transferring the concavo-convex shape of the transfer pattern (more specifically, the concavo-convex inverted shape) (for example, Patent Documents 1 and 2).

  As a template manufacturing method as described above, for example, a hard mask layer such as chromium (Cr) is formed on a template substrate such as a synthetic quartz glass substrate, and the resist pattern formed thereon is used as an etching mask. A method is used in which the hard mask layer is etched, and then the template substrate is etched using the processed hard mask layer (hard mask pattern) as an etching mask to form the transfer pattern.

  In recent years, in order to meet the demand for further miniaturization, as a processing method of the hard mask layer, first, a pattern serving as a core material is formed on the hard mask layer, and a coating film is formed so as to cover the core material pattern. Is etched back to form a sidewall pattern made of the coating film material on the side surface of the core material pattern, and the hard mask layer is etched using this sidewall pattern (referred to as a sidewall process). ) Is proposed (for example, Patent Document 3).

JP-T-2004-504718 JP 2002-93748 A Japanese Patent No. 4825891 Japanese Patent No. 4523661

Here, when inspecting the dimensions and defects of the formed transfer pattern using an SEM (scanning electron beam microscope) or the like, first, the alignment mark formed on the template is found, and the target alignment is obtained from the coordinates of the obtained alignment mark. A method of acquiring position information of a transfer pattern to be used is generally used.
Such an alignment mark is usually formed in the same process as the transfer pattern because the relative position accuracy with the transfer pattern is required. For example, when the resist pattern to be the transfer pattern is formed by electron beam drawing, the electron beam drawing of the resist pattern to be the alignment mark is also processed in one process that is continuous with the electron beam drawing of the transfer pattern.

  However, in the side wall process as described above, the width of the formed side wall pattern is usually the same, and the size is a fine size (for example, about 20 nm) required for the transfer pattern. Therefore, when the template transfer pattern and the alignment mark are formed by using this side wall process, there is a problem that it becomes difficult to find the alignment mark.

  The above will be described more specifically with reference to FIGS. 7 and 8. Here, FIG. 7 is a schematic process diagram showing an example of a conventional method for producing a template for nanoimprint. FIG. 8 is an explanatory view showing an example of an alignment mark of a conventional nanoimprint template, in which (a) is a schematic plan view and (b) is a cross-sectional view taken along line AA in (a).

  When the transfer pattern and the alignment mark are formed using the sidewall process as described above, for example, a hard mask layer 120 is formed on the substrate 110 as shown in FIG. A core material pattern 131 for forming a transfer pattern and a core material pattern 132 for forming an alignment mark are formed using a conventionally known method.

  Next, a coating film 140 is formed so as to cover the core material patterns 131 and 132 (FIG. 7B), and then etched back by anisotropic etching such as RIE (Reactive Ion Etching) to cover the core material patterns 131 and 132. By removing unnecessary portions of the film 140, a side wall pattern 141 is formed on the side surface of the core material pattern 131, and a side wall pattern 142 is formed on the side surface of the core material pattern 132 (FIG. 7C). The material patterns 131 and 132 are removed (FIG. 7D).

  Thereafter, the hard mask layer 120 and the substrate 110 are processed using the side wall patterns 141 and 142 as etching masks, and the transfer pattern 151 and the line pattern 152 constituting the outer edge of the alignment mark 161 are formed on the surface of the substrate 110. A template is obtained (FIG. 7 (e)).

  Even if the alignment mark 161 formed as described above is designed as a cross-shaped mark having a predetermined width (MW) in a plan view as shown in FIG. Thereafter, as shown in FIG. 8B, the line pattern 152 along the outer edge remains.

  Here, the size of the width (MW) is, for example, 50 μm. On the other hand, the width (MEW) of the line pattern 152 is the same as the line width of the transfer pattern. For example, the width (MEW) is about 20 nm, and this size is 1 of the alignment mark width (MW). / 1000 or less. Further, the height (H) of the line pattern 152 is the same as the height of the transfer pattern. For example, the height (H) is about 20 nm.

When such fine isolated line patterns are formed, for example, 50 μm apart from each other, it is difficult for the operator to find out the presence in the inspection by SEM or the like.
Therefore, it has been difficult to find such an alignment mark, that is, to identify it as an alignment mark.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a nanoimprint template capable of easily identifying an alignment mark while using a sidewall process, and a manufacturing method thereof.

  As a result of various studies, the present inventor has found that the above problem can be solved by forming an identification pattern having a configuration in which a plurality of convex structures are arranged in association with an alignment mark using a sidewall process. The present invention has been completed.

  That is, the invention according to claim 1 of the present invention is a method for producing a template for nanoimprint, which includes a transfer pattern, an alignment mark, and an identification pattern that is associated with the alignment mark and has a configuration in which a plurality of convex structures are arranged. The step of forming the first core material pattern for forming the transfer pattern, the second core material pattern for forming the alignment mark, and the third core material pattern for forming the identification pattern. Forming a coating film on the upper surface and side surfaces of each of the first core material pattern, the second core material pattern, and the third core material pattern, and the first core material pattern The other coating films are removed so as to leave the coating films formed on the respective side surfaces of the second core material pattern and the third core material pattern. Removing the first core material pattern, the second core material pattern, and the third core material pattern to form a sidewall pattern composed of the coating film; and And a step of forming the transfer pattern, the alignment mark, and the identification pattern by processing using a sidewall pattern as an etching mask.

  In the invention according to claim 2 of the present invention, the third core material pattern includes a line and space pattern in which a plurality of line patterns are arranged, and a space width of the line and space pattern is a film of the coating film. 2. The method for producing a template for nanoimprint according to claim 1, wherein the size is not less than 1 and not more than 2 times the thickness.

  The invention according to claim 3 of the present invention is characterized in that an outer edge of the alignment mark is formed by one or more line patterns, and the identification pattern is arranged in a region surrounded by the line patterns. A method for producing a template for nanoimprinting according to claim 1 or 2.

  Further, in the invention according to claim 4 of the present invention, a part of the outer edge of the alignment mark is constituted by the identification pattern, and the nanoimprint according to any one of claims 1 to 3 It is a manufacturing method of the template for use.

  In the invention according to claim 5 of the present invention, the first core material pattern, the second core material pattern, and the third core material pattern are formed of a resin pattern to constitute the resin pattern. The method for producing a nanoimprint template according to any one of claims 1 to 4, wherein the coating film is formed by an atomic layer deposition method at a temperature lower than a glass transition temperature of a resin to be formed. It is.

  Further, the invention according to claim 6 of the present invention is a nanoimprint template having a transfer pattern, an alignment mark, and an identification pattern having a configuration in which a plurality of convex structures are arranged accompanying the alignment mark. The identification pattern includes a line and space pattern in which a plurality of line patterns are arranged, and the line width of the line and space pattern is not less than 1 and not more than twice the size of the space width. This is a featured template for nanoimprint.

  In the invention according to claim 7 of the present invention, an outer edge of the alignment mark is configured by one or more line patterns, and the identification pattern is disposed in a region surrounded by the line patterns. The nanoimprint template according to claim 6, wherein the template is a nanoimprint template.

  The invention according to claim 8 of the present invention is the nanoimprint template according to claim 6 or 7, wherein a part of an outer edge of the alignment mark is configured by the identification pattern. is there.

  According to the present invention, the alignment mark can be easily identified while using the sidewall process.

It is a schematic process drawing which shows an example of the manufacturing method of the template for nanoimprint which concerns on this invention. In this invention, it is explanatory drawing which shows an example of the line and space pattern formed in one template. In this invention, it is explanatory drawing which shows the other example of the line and space pattern formed in one template. It is a schematic plan view which shows an example of the alignment mark and identification pattern which concern on this invention. It is a schematic plan view which shows the other example of the alignment mark which concerns on this invention, and an identification pattern. It is explanatory drawing which shows the example of the form of the alignment mark which concerns on this invention. It is a schematic process drawing which shows an example of the manufacturing method of the conventional template for nanoimprint. It is explanatory drawing which shows an example of the alignment mark of the conventional template for nanoimprint, (a) is a schematic plan view, (b) is AA sectional drawing in (a).

  Hereinafter, a template for nanoimprinting and a manufacturing method thereof according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic process diagram showing an example of a method for producing a nanoimprint template according to the present invention.
In order to manufacture a nanoimprint template having a transfer pattern, an alignment mark, and an identification pattern using the manufacturing method according to the present invention, for example, as shown in FIG. A mask layer 20 is formed, on which a first core material pattern 31 for forming a transfer pattern, a second core material pattern 32 for forming an alignment mark, and a second core material pattern for forming an alignment mark A third core material pattern 33 for forming an identification pattern, which is provided in the vicinity of 32 and includes a plurality of convex structures, is formed.

  Here, the substrate 10 can be used as long as it can be applied to the template for nanoimprinting. For example, a transparent substrate such as quartz glass, calcium fluoride, and magnesium fluoride can be used. In general, a synthetic quartz glass substrate is used.

  The material constituting the hard mask layer 20 can be any material that can act as an etching mask when the substrate 10 is etched to form a transfer pattern. For example, chromium (Cr ), Molybdenum (Mo), titanium (Ti), tantalum (Ta), and the like, and their oxides, nitrides, oxynitrides, and the like. The hard mask layer 20 may be a single layer film or a multilayer film.

Moreover, as a material which comprises the 1st core material pattern 31, the 2nd core material pattern 32, and the 3rd core material pattern 33, if it is the material used as a core material in the conventional side wall process In the present invention, it is preferable to use an organic material such as a resist resin used for electron beam drawing or a curable resin used for nanoimprint lithography.
Since the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 can be directly formed as a resin pattern by electron beam drawing or nanoimprint, For example, since Patent Document 3) first forms a resist pattern and uses this resist pattern as an etching mask to form a core material pattern, the process can be shortened and the manufacturing cost can be kept low. is there.
In addition, the 1st core material pattern 31, the 2nd core material pattern 32, and the 3rd core material pattern 33 use the technique similar to the conventional method for the resin pattern formed by electron beam drawing or nanoimprint. It may be formed by slimming.

  Here, in order to maintain relative positional accuracy, the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 are preferably formed in the same process. For example, when the first core material pattern 31 for forming the transfer pattern is formed by electron beam drawing, the second core material pattern 32 for forming the alignment mark and the third core material for forming the identification pattern The electron beam drawing of the pattern 33 is also processed in one continuous process.

  Next, a coating film 40 is formed on the top and side surfaces of each of the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 (FIG. 1B). Next, etch back is performed by anisotropic etching such as RIE (Reactive Ion Etching) and the like on the side surfaces of the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33. The other coating film 40 is removed while leaving the formed coating film 40 (FIG. 4C).

Here, as a method of forming the coating film 40, any method can be used as long as it is a method of forming a coating film applicable to the sidewall process. In the present invention, an atomic layer deposition method (ALD method: Atomic) is used. The Layer Deposition method) is preferably used.
This is because if the atomic layer deposition method is used, a film can be formed in units of atomic layers, and a film having high shape following property and high film thickness uniformity can be formed.

  This atomic layer deposition method is a technology for forming a thin film (atomic layer deposition film) on an atomic layer unit on a substrate by alternately using a source gas containing metal or silicon and a reaction gas containing oxygen, fluorine, or the like, The four steps of supplying a gas containing metal or silicon, eliminating excess gas, supplying gas containing oxygen, etc., and eliminating excess gas are set as one cycle, and this is repeated a plurality of times to form a film having a desired thickness. This is a film forming technique (for example, Patent Document 4).

  In the present invention, for example, a silicon oxide film can be formed as the coating film 40 by alternately using a source gas containing silicon and a reaction gas containing oxygen. Similarly, a silicon nitride film can be formed using the coating film 40 by using a source gas containing silicon and a reaction gas containing nitrogen.

In addition, if the film formation method is based on the atomic layer deposition method, it is possible to form a high-quality thin film at a lower temperature (for example, room temperature) than the film formation method based on the conventional CVD (Chemical Vapor Deposition) method.
Therefore, in the present invention, as described above, the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 are formed of a resin pattern, and this resin pattern is configured. It is preferable to form the coating film 40 by an atomic layer deposition method at a temperature lower than the glass transition temperature of the resin to be processed. This is because the resin pattern can be prevented from being deformed by heat.

  Next, the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 are removed to form side wall patterns 41, 42, 43 composed of the coating film 40. (FIG. 1 (d)).

  Thereafter, the hard mask layer 20 and the substrate 10 are processed using the sidewall patterns 41, 42, and 43 as an etching mask to form a transfer pattern 51, a line pattern 52 that constitutes the outer edge of the alignment mark, and an identification pattern 53. Thus, template 1 is obtained (FIG. 1 (e)).

  In the example shown in FIG. 1, the hard mask layer 20 is formed on the substrate 10, and each of the core material patterns is formed on the hard mask layer 20. Without being limited thereto, the above core material patterns may be formed on the substrate 10 without forming a hard mask layer.

The template 1 obtained as described above has an identification pattern 53 attached to the alignment mark.
Since the identification pattern 53 has a configuration in which a plurality of convex structures are arranged in the existence area, the identification pattern 53 has a configuration in which a fine isolated line pattern as in the conventional case only remains along the outer edge. It is easy to find out. And it becomes easy to find the alignment mark accompanying this identification pattern. The identification pattern 53 can be configured such that, for example, a plurality of convex structures having a width of several tens of nm are adjacent to each other and at least cover a region having a width of 500 nm to 1 μm.

  In the present invention, it is sufficient that the position of the alignment mark can be generally known by the identification pattern 53. More accurate positioning is performed based on the position information of the alignment mark obtained by the identification pattern, for example, An edge detection method using electron beam scanning may be used.

  As the convex structure constituting the identification pattern 53, even if each individual structure has a minute size, any structure can be used as long as it can be distinguished by arranging a plurality of structures. In view, a line type, a ring type (cylinder type), a cylindrical type, and various polygonal prism types can be exemplified.

Here, in the present invention, a line-and-space pattern in which the space width is not less than 1 time and not more than twice the film thickness of the coating film 40 is formed in the third core material pattern 33. Is preferred.
This is because a line and space pattern having a larger line width than the 1: 1 line and space pattern that is normally formed by using the sidewall process can be formed as the identification pattern 53, and the discrimination is improved.

The above will be described with reference to FIGS.
Here, FIG. 2 is an explanatory diagram showing an example of a line and space pattern formed on one template in the present invention, and shows an example of a 1: 1 line and space pattern that the transfer pattern has, for example. .
FIG. 3 is an explanatory diagram showing another example of the line and space pattern formed on one template in the present invention, for example, an example of the line and space pattern included in the identification pattern.

For example, in the present invention, when forming a fine 1: 1 line and space pattern as required for the transfer pattern, as shown in FIG. The space width (SW1) of 33a may be designed to be three times the film thickness (T) of the coating film 40.
In this case, as shown in FIG. 2B, the width (LW1) of the sidewall pattern 43a formed from the coating film 40 is the same as the film thickness (T) of the coating film 40. A line-and-space pattern 53a formed on the substrate 10 using 43a as an etching mask also has a line width (LW1) that is the same as the film thickness (T) of the coating film 40 (FIG. 2C). .
For example, a 1: 1 line and space pattern included in the transfer pattern 51 shown in FIG. 1E is also formed as described above.

On the other hand, in the present invention, when a suitable line and space pattern is formed as the identification pattern, the space width (SW2) of the core material pattern 33b is set to the film thickness of the coating film 40 as shown in FIG. The size is designed to be at least 1 and not more than 2 times (T).
In this case, the space between the core material patterns 33 b is filled with the coating film 40. Therefore, as shown in FIG. 3B, the width (LW2) of the side wall pattern 43b formed from the coating film 40 is the same as the space width (SW2) of the core material pattern 33b. The line-and-space pattern 53b formed on the substrate 10 using the pattern 43b as an etching mask also has the same line width (LW2) as the space width (SW2) of the core material pattern 33b (FIG. 3C). ).
The line width (LW2) of the line and space pattern 53b is larger than the line width (LW1) of the line and space pattern 53a shown in FIG.
For example, the line and space pattern included in the identification pattern 53 shown in FIG. 1E is also formed as described above.

Here, when the space width of the core material pattern is larger than twice the film thickness of the coating film 40, the space between the core material patterns is formed by the coating film 40 as in the embodiment shown in FIG. The width of the side wall pattern formed without being filled is the same as the film thickness of the coating film 40.
The line width of the line-and-space pattern formed on the substrate 10 using this sidewall pattern as an etching mask also becomes the same as the film thickness of the coating film 40.
Therefore, in this case, a line and space pattern having a larger line width than the 1: 1 line and space pattern normally formed by using the sidewall process cannot be formed as the identification pattern.

In addition, when the space width of the core material pattern is smaller than 1 times the film thickness of the coating film 40, the space between the core material patterns is filled with the coating film 40 as in the embodiment shown in FIG. Therefore, the width of the side wall pattern to be formed is the same as the space width of the core material pattern.
The width of the line and space pattern formed on the substrate 10 using the sidewall pattern as an etching mask is the same as the space width of the core material pattern. The film thickness is smaller than 1 time.
Therefore, in this case, a line-and-space pattern having a smaller line width than a 1: 1 line-and-space pattern normally formed by using a sidewall process is obtained.
That is, also in this case, a line and space pattern having a larger line width than the 1: 1 line and space pattern that is normally formed by using the sidewall process cannot be formed as the identification pattern.

  Therefore, in the present invention, as described above, the space width (SW2) of the core material pattern 33b is formed to be not less than 1 and not more than twice the film thickness (T) of the coating film 40. In particular, the space width (SW2) of the core material pattern 33b is preferably formed to be twice as large as the film thickness (T) of the coating film 40.

Here, as shown in FIG. 3, the space width of the line and space pattern 53b is the same as the width of the core material pattern 33b.
And, when trying to form the width of the core material pattern 33b to the minimum, that is, when trying to form the width of the third core material pattern 33 for forming the identification pattern shown in FIG. The width is the same as the width of the first core material pattern 31 for forming the transfer pattern 51 having a 1: 1 line and space pattern.
Here, the width of the first core material pattern 31 for forming the transfer pattern is the same as the space width of the transfer pattern 51 shown in FIG. 1 (e), and this size is shown in FIG. 1 (d). It is the same size as the width of the side wall pattern 41 shown, and this size is the same size as the film thickness of the coating film 40 shown in FIG.
As described above, in the line-and-space pattern formed in the third core material pattern 33, the space width is not less than 1 time and not more than twice the film thickness of the coating film 40. Is preferred.

  Therefore, in the case where a line and space pattern is formed in the identification pattern 53, if the line width is made larger and the space width is made smaller in order to improve discrimination, the size of the line width is The space width is preferably at least 1 time and not more than 2 times, and among these, the line width is preferably formed to be twice the space width.

  In the present invention, as the value of the film thickness (T) of the coating film 40, for example, a value obtained in advance through experiments or the like under the same film deposition conditions can be used. Can be used, the average value in the region where the transfer pattern is formed can be used.

  In the present invention, the line width of the line and space pattern can be, for example, a width at a position that is half the height of the line pattern in a cross-sectional view. Similarly, the space width of the line and space pattern is The width at the position of ½ of the depth of the space pattern in a sectional view can be obtained.

Next, the arrangement relationship between the identification pattern 53 and the alignment mark will be described.
In the present invention, the identification pattern 53 may be separated from the alignment mark or may be integrated with the alignment mark. Moreover, it may constitute a part of the outer edge of the alignment mark.

  For example, as shown in FIG. 4, in the present invention, the outer edge of the alignment mark 61 is formed by the line pattern 52, and the identification pattern 53 can be disposed in a region surrounded by the line pattern 52.

In this case, the identification pattern 53 only has to contribute to finding the position of the alignment mark 61. Therefore, a region occupied by the identification pattern 53 (that is, a region where a plurality of convex structures are arranged) is a small area. For example, the electron beam drawing time for forming the identification pattern 53 can be shortened, and the manufacturing cost can be kept low.
On the other hand, the alignment mark 61 may be positioned with high accuracy by, for example, scanning the line pattern 52 with an electron beam and detecting an edge.

The size of the area occupied by the identification pattern 53 may be any size that can be easily found by observation with an SEM or the like. For example, in the example shown in FIG. 4, the shorter width (DW) is about 500 nm to 1 μm and long. The width (DL) can be about 2 to 3 times the width (DW).
The alignment mark 61 has, for example, a width (MW) of 50 μm and a total length (ML) of 1 mm.

  The identification pattern 53 in the present embodiment is preferably arranged at a position where the center of the alignment mark 61 or the outer edge can be easily recognized. For example, as shown in FIG. 4, it is preferable to arrange symmetrically in the vicinity where the cross of the alignment mark 61 intersects. This is because the center of the alignment mark 61 can be easily recognized even if the area occupied by the identification pattern 53 is a small area.

In the present invention, as shown in FIG. 5, the entire alignment mark 62 can be formed by line and space patterns 54a, 54b and 54c. That is, in the present embodiment, the line and space patterns 54 a, 54 b, 54 c are identification patterns and are integrated with the alignment mark 62.
For example, the alignment mark 62 has a width (MW) of 50 μm and a total length (ML) of 1 mm.

In this case, the alignment mark 61 may be positioned with high accuracy by, for example, scanning the outermost line patterns of the line-and-space patterns 54a, 54b, 54c with an electron beam and detecting edges.
Therefore, the line and space patterns 54a, 54b, 54c are preferably formed perpendicular to the direction of electron beam scanning for mark detection.
For example, as in the example shown in FIG. 5, the portion where the longitudinal direction of the cross-shaped alignment mark 62 is the X direction is formed by a line-and-space pattern 54 a in which the line pattern extends along the X direction. The portion in which the longitudinal direction of 62 is the Y direction is formed by line and space patterns 54b and 54c in which the line pattern extends along the Y direction.

  In the present invention, for example, as shown in FIGS. 6A and 6B, the identification pattern may constitute a part of the outer edge of the alignment mark. In FIG. 6, the identification pattern is indicated by a hatched portion.

  In addition, the planar form of the alignment mark according to the present invention is not limited as long as it can be applied as an alignment mark, and other than the cross shape, for example, an L-shape (FIG. 6 (d)), or a cross-shaped mark, an L-shaped mark, and a vocabulary mark may be formed by an array of rectangular patterns (FIGS. 6 (e) to (g). )).

  The nanoimprint template and the manufacturing method thereof according to the present invention have been described above, but the present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the technical idea described in the claims of the present invention has substantially the same configuration and exhibits the same function and effect regardless of the case. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1
A synthetic quartz glass substrate was used as the substrate 10, and a CrN film as a hard mask layer 20 was formed thereon by sputtering to a thickness of 5 nm.

  Next, an electron beam resist is formed on the hard mask layer 20 with a film thickness of 60 nm, electron beam drawing is performed, a first core material pattern 31 for forming a transfer pattern, and a second core for forming an alignment mark. A material pattern 32 and a third core material pattern 33 for forming an identification pattern were formed.

  Here, a line-and-space pattern having a line width of 15 nm and a space width of 45 nm is formed as the first core material pattern 31, and a cross-shaped pattern as shown in FIG. 4 is used as the second core material pattern 32. The third core material pattern 32 is a line-and-space pattern having a line width of 15 nm and a space width of 30 nm, and a cross shape of the second core material pattern 32. It was formed in the area of the mold pattern.

Next, a source film containing silicon and a reaction gas containing oxygen are alternately supplied at a low temperature of 100 ° C. or lower by using an atomic layer deposition method to form a coating film 40 made of a silicon oxide film having a thickness of 15 nm. The first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 are formed on the upper surface and side surfaces of the first core material pattern 31, and then etched back by dry etching using CF ₄ gas. Then, the other coating films 40 are removed while leaving the coating films 40 formed on the respective side surfaces of the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33. did.

  Next, the first core material pattern 31, the second core material pattern 32, and the third core material pattern 33 are removed by an ashing process using oxygen gas, and the coating film 40 is formed. Sidewall patterns 41, 42, and 43 were formed.

Thereafter, the hard mask layer 20 is dry-etched using a mixed gas of chlorine and oxygen using the side wall patterns 41, 42, and 43 as an etching mask, and then the substrate 10 is etched 20 nm deep using CF ₄ gas. Then, the sidewall patterns 41, 42 and 43 are removed, and finally, the hard mask layer 20 is removed by dry etching using a mixed gas of chlorine and oxygen, and a transfer pattern having a 15 nm 1: 1 line and space pattern is obtained. An alignment mark bordered by a line pattern 52 having a width of 51, 15 nm and an identification pattern 53 having a line-and-space pattern having a line width of 30 nm and a space width of 15 nm were formed to obtain a template 1.

  When the template 1 was observed with an SEM, the identification pattern 53 could be easily found, thereby easily recognizing the center of the alignment mark.

DESCRIPTION OF SYMBOLS 1 ... Template 10 ... Board | substrate 20 ... Hard mask layer 31 ... 1st core material pattern 32 ... 2nd core material pattern 33 ... 3rd core material pattern 40 ... Cover film 41, 42, 43 ... sidewall pattern 51 ... transfer pattern 52 ... line pattern 53 ... identification pattern 33a, 33b ... core material pattern 43a, 43b ... sidewall pattern 53a 53b ... Line and space patterns 54a, 54b, 54c ... Line and space patterns 61, 62 ... Alignment mark 101 ... Template 110 ... Substrate 120 ... Hard mask layer 131, 132 ..Core material pattern 140 ... Coating film 141, 142 ... Side wall pattern 151 ... Transfer pattern 152 ... Lye Pattern 161 ... alignment mark

Claims (8)

A method for producing a template for nanoimprint having a transfer pattern, an alignment mark, and an identification pattern having a configuration in which a plurality of convex structures are arranged, attached to the alignment mark,
Forming a first core material pattern for forming the transfer pattern, a second core material pattern for forming the alignment mark, and a third core material pattern for forming the identification pattern;
Forming a coating film on the upper surface and side surfaces of each of the first core material pattern, the second core material pattern, and the third core material pattern;
Other coating films are removed so as to leave the coating films formed on the respective side surfaces of the first core material pattern, the second core material pattern, and the third core material pattern. And a process of
Removing the first core material pattern, the second core material pattern, and the third core material pattern to form a sidewall pattern composed of the coating film;
Forming the transfer pattern, the alignment mark, and the identification pattern by processing using the sidewall pattern as an etching mask;
A method for producing a template for nanoimprinting, comprising:   The third core material pattern includes a line-and-space pattern in which a plurality of line patterns are arranged, and the space width of the line-and-space pattern is greater than or equal to 1 and less than or equal to 2 times the film thickness of the coating film. The method for producing a template for nanoimprinting according to claim 1, wherein Forming an outer edge of the alignment mark with one or more line patterns;
The method for producing a nanoimprint template according to claim 1, wherein the identification pattern is disposed in a region surrounded by the line pattern.   The method for producing a nanoimprint template according to any one of claims 1 to 3, wherein a part of an outer edge of the alignment mark is configured by the identification pattern. Forming the first core material pattern, the second core material pattern, and the third core material pattern with a resin pattern;
The nanoimprint according to any one of claims 1 to 4, wherein the coating film is formed by an atomic layer deposition method at a temperature lower than a glass transition temperature of a resin constituting the resin pattern. Template manufacturing method. A template for nanoimprint having a transfer pattern, an alignment mark, and an identification pattern having a configuration in which a plurality of convex structures are arranged, attached to the alignment mark,
The identification pattern includes a line and space pattern in which a plurality of line patterns are arranged, and the line width of the line and space pattern is not less than 1 and not more than twice the size of the space width. A template for nanoimprint. The outer edge of the alignment mark is composed of one or more line patterns,
The nanoimprint template according to claim 6, wherein the identification pattern is disposed in a region surrounded by the line pattern. 8. The nanoimprint template according to claim 6, wherein a part of an outer edge of the alignment mark is configured by the identification pattern. 9.

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