JP6171424B2 - Manufacturing method and design method of imprint mold - Google Patents

Description

  The present invention relates to a method for manufacturing and designing an imprint mold.

  Nanoimprint technology, known as microfabrication technology, uses a mold member (imprint mold) in which a fine concavo-convex pattern is formed on the surface of a substrate, and transfers the fine concavo-convex pattern to a workpiece to produce fine concavo-convex This is a pattern formation technique for transferring a pattern at an equal magnification (see Patent Document 1). In particular, with further miniaturization of wiring patterns and the like in semiconductor devices, nanoimprint technology is gaining more and more attention in semiconductor device manufacturing processes and the like.

  In this nanoimprint technology, generally, an imprint resin as a workpiece is applied on a substrate, and the imprint resin is cured in a state where the imprint resin and the imprint mold are in contact with each other, thereby imprint mold. A fine concavo-convex pattern structure formed by transferring the fine concavo-convex pattern is formed. As a method of applying the imprint resin on the substrate, an ink jet method or the like in which the imprint resin is discretely dropped onto a predetermined position on the substrate surface (surface on which the fine uneven pattern structure is formed) is known.

  When forming a fine concavo-convex pattern structure by nanoimprinting, it is required that the film thickness (remaining film thickness) of the concave portions in the fine concavo-convex pattern structure is uniform throughout. If there is unevenness in the thickness of the remaining film, when using the fine concavo-convex pattern structure as an etching mask, the etching accuracy is reduced, and the size of the fine concavo-convex pattern formed on the substrate by etching will vary. There's a problem.

  In order to solve such a problem, as a technique for suppressing the occurrence of variation in the remaining film thickness in the fine uneven pattern structure, various methods related to a dripping method of an imprint resin using a resin coating apparatus by an ink jet method have been conventionally used. Has been proposed (see Patent Documents 2 and 3).

In a resin coating apparatus using an ink jet method, generally, an imprint resin is dropped onto a substrate by scanning an ink jet head having a plurality of resin discharge ports (nozzles) provided at predetermined intervals in a predetermined direction. The position where the imprint resin is actually dropped on the substrate is determined by the nozzle interval, the scanning speed of the inkjet head, the timing of dropping the imprint resin from the nozzle, and the like. In the resin coating apparatus as described above, if parameters such as the nozzle interval, the scanning speed of the ink jet head, and the timing of dropping the imprint resin from the nozzle can be freely set (controlled), it can be within a predetermined area on the substrate. The imprint resin can be dropped at any position. However, in the resin coating apparatus as described above, the above parameters and the like can be set only by selecting a specific value within a predetermined range for each resin coating apparatus or within the range. Will be imposed a limit. In addition, the settable range of the above parameters (particularly the dropping timing) may be further limited by physical properties such as viscosity and surface tension of the imprint resin to be used. Therefore, in the resin coating apparatus as described above, in the scanning direction of the inkjet head (each of the main scanning direction and the sub-scanning direction) determined by restrictions on the apparatus and physical characteristics of the imprint resin to be used. The imprint resin is dropped only at intervals of an integral multiple of a grid (in general, each intersection of grid lines parallel to each of the main scanning direction and the sub-scanning direction of the inkjet head) with a minimum predetermined interval (about several μm) along the line. There is a restriction that it cannot be done. Moreover, it is very difficult to control the amount of one imprint resin droplet, which is a very small amount of several pL (several thousand μm ³ ), to be increased or decreased for each drop (one droplet).

  In the inventions described in Patent Documents 2 and 3, in order to make the remaining film thickness of the fine concavo-convex pattern structure uniform, the position at which the imprint resin is dropped on the transfer surface such as the substrate and the amount to be dropped are set. Although controlled, when the resin coating apparatus as described above is used, the imprint resin cannot be dropped at a position off the resin dropping grid, and it is difficult to increase or decrease the appropriate amount of liquid. Therefore, it is extremely difficult to control the dropping position and dropping amount of the imprint resin as in the inventions described in Patent Documents 2 and 3, unless a resin coating apparatus having a special mechanism is used.

  Further, in the inventions described in Patent Documents 2 and 3, when the imprint resin droplets are wetted and spread when they come into contact with the imprint mold, the droplets having a substantially circular shape in plan view are substantially isotropic. The dripping position is determined on the premise of spreading in a circular shape (radial). However, if the type (structure, etc.) of the fine concavo-convex pattern of the imprint mold is different, the way in which the imprint resin droplets spread out may be different. For example, when the fine concavo-convex pattern of the imprint mold is a line-and-space pattern, the imprint resin droplets tend to wet and spread in a direction substantially parallel to the line direction, but in a direction substantially perpendicular to the line direction. Print resin droplets do not spread easily. For this reason, the inventions described in Patent Documents 2 and 3 have a problem that unevenness may occur in the remaining film thickness depending on the type of the fine uneven pattern of the imprint mold.

  In order to solve such a problem, conventionally, the distance between imprint resin droplets along the direction substantially parallel to the line direction in the line-and-space fine concavo-convex pattern is long and along the direction substantially perpendicular to the line direction. A nanoimprint method for applying imprint resin droplets so as to shorten the interval between the imprint resin droplets has been proposed (see Patent Document 4).

  On the other hand, the size of the fine concavo-convex pattern in the fine concavo-convex pattern structure is improved by improving the releasability of the imprint mold from the cured imprint resin and the filling property of the imprint resin into the concave portion of the imprint mold. Various techniques for suppressing a decrease in accuracy and occurrence of defects have been proposed.

  For example, a fine unevenness adjacent to and adjacent to a fine unevenness pattern on the imprint mold (a fine unevenness pattern to be transferred to an imprint resin as a workpiece, hereinafter sometimes referred to as a “main pattern”). By providing a pattern (a fine concavo-convex pattern that does not need to be originally transferred to the imprint resin as a workpiece, sometimes referred to as a “dummy pattern” hereinafter) There has been proposed a technique that improves the filling property of the imprint resin to the surface and suppresses the decrease in the dimensional accuracy of the fine concavo-convex pattern in the fine concavo-convex pattern structure, the occurrence of defects, and the like (see Patent Document 5).

US Pat. No. 5,772,905 JP 2009-88376 A JP 2012-54322 A JP2011-228619A JP 2010-225683 A

  As described in Patent Document 5, a region (pattern formation region) where a fine uneven pattern on an imprint mold is formed, and a region where a fine uneven pattern adjacent to the pattern formation region is not formed ( Since the contact area with the imprint resin is different from the pattern non-formation region), the force required for peeling the imprint mold is different for each region. For this reason, the peeling speed of the imprint mold changes abruptly at the boundary between the two regions, whereby the fine concavo-convex pattern is torn off and a defect is generated. Moreover, even if it is not completely torn off, the dimensional accuracy is lowered by stretching the imprint resin.

  Therefore, as in the invention described in Patent Document 5, a dummy pattern is formed in the pattern non-formation region, and the contact area with the imprint resin in the region is increased, thereby adjoining the pattern formation region. Abrupt fluctuations in the imprint mold peeling speed can be suppressed at the boundary with the pattern non-formation area (area where the dummy pattern is formed), resulting in a decrease in the dimensional accuracy of the fine concavo-convex pattern and the occurrence of defects. Can be prevented.

  However, in the invention described in Patent Document 5, since the main purpose is only to reduce the difference between the contact area in the pattern formation region and the contact area in the pattern non-formation region, the pattern non-formation region Depending on the type of dummy pattern to be formed, the main pattern part (pattern formation area) and the dummy pattern part (pattern non-formation area where the dummy pattern is formed) differ greatly in the way in which the imprint resin wets and spreads. The remaining film thickness of the uneven pattern structure cannot be made uniform as a whole. Therefore, there is a problem that it is not possible to suppress a decrease in the dimensional accuracy of the fine concavo-convex pattern and the occurrence of defects due to the variation in the remaining film thickness of the fine concavo-convex pattern structure.

  In view of the above problems, the present invention can substantially uniform the remaining film thickness in the concavo-convex pattern structure as a whole, reducing the dimensional accuracy of the concavo-convex pattern in the concavo-convex pattern structure, generating defects, etc. It is an object of the present invention to provide a method for manufacturing an imprint mold having at least two types of uneven patterns and a method for designing the imprint mold that can be prevented.

In order to solve the above problems, the present invention is a method of manufacturing an imprint mold in which at least two types of concave / convex patterns are formed on a pattern forming surface, and the pattern formation is performed from among a plurality of types of concave / convex patterns. A concavo-convex pattern selection step for selecting at least one concavo-convex pattern of at least two types of concavo-convex patterns to be formed on the surface, and an in-plane corresponding to the pattern forming surface on the substrate constituting the imprint mold A concavo-convex pattern forming step for forming each of the at least two types of concavo-convex patterns including the selected concavo-convex pattern selected in the concavo-convex pattern selecting step in each of the at least two pattern forming regions, pattern selection process can dropwise imprint resin only on the intersection of a given grid line A resin coating device, the imprint resin spread wet on the transferred surface in by contacting the patterned surface of discrete dripped imprinted resin and imprint mold to the transferred surface by an ink-jet method The remaining film thickness group of the uneven pattern structure obtained by curing, the remaining film thickness group including a plurality of remaining film thicknesses that can be formed substantially uniformly corresponding to each of the plurality of types of uneven patterns. A step of obtaining for each type of uneven pattern, and a remaining film thickness that can be formed substantially uniformly corresponding to an uneven pattern other than the at least one selected uneven pattern among the at least two types of uneven patterns. Are extracted from the plurality of remaining film thicknesses included in each remaining film thickness group of the plurality of types of uneven patterns, and the extracted remaining film thickness Corresponding said and the step of determining at least one concavo-convex pattern, a plurality of residual film thickness contained in the residual film Atsugun are each droplet of the imprint resin is determined according to the uneven pattern determined based on the basic arrangement pattern and the basic arrangement pattern of size to provide a method of manufacturing an imprint mold, wherein Rukoto (invention 1).

  According to the said invention (invention 1), the pattern formation of an imprint mold is carried out so that the residual film thickness of the uneven | corrugated pattern structure obtained by the imprint using an imprint mold can be made substantially uniform as a whole. Since at least one type of concavo-convex pattern is selected from at least two types of concavo-convex patterns formed on the surface, an imprint mold capable of forming a concavo-convex pattern structure with high dimensional accuracy and no pattern defects is manufactured. can do.

  In the present invention, when the imprint resin droplet is brought into contact with the imprint mold droplet, the imprint resin droplet wets and spreads (the shape and size of the wet spread droplet, the wetness). The concavo-convex patterns having different spreading directions (directions in which the liquid droplets wet and spread more easily) are different types of concavo-convex patterns. Concave and convex patterns with different structures such as line and space shape, hole shape, pillar shape, lattice shape, etc., and concave and convex dimensions (dimensions in a plan view) and concave and convex portions with different depths even with the same structure In principle, the patterns and the like are different types of uneven patterns. For example, even if the uneven pattern has a line and space shape, the uneven pattern with a dimension of 50 nm and the uneven pattern with a dimension of 100 nm are different types of uneven patterns because the way in which the imprint resin wets and spreads is different. Moreover, even if the structure, dimensions, and depth of the concave portions are the same, the concave / convex patterns having different directions of wet spread of the imprint resin droplets are different types of concave / convex patterns. For example, even if the concavo-convex pattern is a line-and-space shape having the same dimensions and the same recess depth, the concavo-convex pattern in which the line directions intersect each other is a different type of concavo-convex pattern.

In the above invention (Invention 1) , in the concavo-convex pattern selection step, the remaining film thicknesses that can be formed substantially uniformly corresponding to each of the at least two types of concavo-convex patterns substantially match each other, and The drop placement of the imprint resin on the transfer surface related to each remaining film thickness that can be formed substantially uniformly corresponding to each of at least two types of concavo-convex patterns is similar to each other. It is preferable to select at least one type of uneven pattern (Invention 2 ).

In the said invention (invention 1 and 2 ), the said imprint mold is a thing in which at least 3 types of uneven | corrugated pattern is formed in the said pattern formation surface, The said pattern on the base material which comprises the said imprint mold at least three patterned regions are positioned to the corresponding plane to form surface, further comprising said at least three kinds of the uneven pattern forming position determining step of each of the uneven pattern to determine the position is formed, the uneven pattern formed In the position determining step, the remaining film thickness that can be substantially formed corresponding to the concave / convex pattern formed in one pattern formation region of the at least three pattern formation regions, and adjacent to the one pattern formation region irregularities formed on the region close to the one of the pattern formation region in the other pattern formation region As the difference between the substantially uniformly formable residual film thickness is minimized in response to the turn, preferably to determine the location of each of which is formed of at least three kinds of concave-convex pattern (Invention 3) .

In the said invention (invention 1-3 ), the auxiliary | assistant uneven | corrugated pattern which selects the auxiliary | assistant uneven | corrugated pattern for assisting the imprint process using the said imprint mold formed in the gap | interval of the two said adjacent pattern formation area | regions. Each of the remaining films that can be formed substantially uniformly corresponding to each of the two types of concavo-convex patterns formed in each of the two adjacent pattern forming regions in the auxiliary concavo-convex pattern selecting step An auxiliary concavo-convex pattern that can form a concavo-convex pattern structure having a substantially uniform remaining film thickness that is substantially the same as the thickness is selected, and is selected in the concavo- convex pattern selection step in the concavo- convex pattern formation step. in each of two of said pattern formation region wherein adjacent each of the two kinds of concave-convex pattern comprising the selected uneven pattern Preferably formed in a gap between two of the pattern forming region of the selected auxiliary convex pattern to said adjacent while forming (invention 4).

In the said invention (invention 1-4 ), the residual film thickness which can be formed substantially uniformly corresponding to the said uneven | corrugated pattern is based on the basic arrangement pattern of the droplet of the said imprint resin, and the size of the said basic arrangement pattern. And is preferably calculated by the following formula (Invention 5 ).
Hr = {Dp− (α / 100 × S × Hp)} / S
In the formula, Hr is “residual film thickness (μm) having a substantially uniform thickness”, Dp is “amount of imprint resin filling the basic arrangement pattern (μm ³ )”, and α is “imprint mold The area ratio (%) of the recesses of the concavo-convex pattern, “Hp” represents “depth of the recesses of the concavo-convex pattern of the imprint mold (μm)”, and S represents the “area of the basic arrangement pattern (μm ² )”.

In the said invention (invention 1-5 ), at least 1 type of uneven | corrugated pattern of the said at least 2 types of uneven | corrugated pattern is a main pattern which should be transcribe | transferred in the uneven | corrugated pattern structure obtained using the said imprint mold. It is preferable (Invention 6 ).

In the said invention (invention 1-6 ), at least 1 type of uneven | corrugated pattern selected in the said uneven | corrugated pattern selection process is for assisting peeling of the said imprint mold in the imprint process using the said imprint mold. A dummy pattern is preferred (Invention 7 ).

In addition, the present invention is a method for designing an imprint mold in which at least two types of uneven patterns are formed on a pattern forming surface, and at least 2 formed on the pattern forming surface from a plurality of types of uneven patterns. A concavo-convex pattern selecting step of selecting at least one concavo-convex pattern among the types of concavo-convex patterns, wherein the concavo-convex pattern selecting step is a resin coating apparatus capable of dropping imprint resin only on intersections of predetermined grid lines. Used by curing the imprint resin wetted and spread within the transfer surface by bringing the imprint resin discretely dropped onto the transfer surface by the inkjet method into contact with the pattern forming surface of the imprint mold. there in residual film thickness of the concavo-convex pattern structure is, to correspond to each of the plurality of types of uneven pattern A step of obtaining a remaining film thickness group including a plurality of remaining film thicknesses that can be formed substantially uniformly for each of the plurality of types of uneven patterns; and at least one selected from among the at least two types of uneven patterns. A plurality of remaining film thicknesses included in each of the remaining film thickness groups of the plurality of concavo-convex patterns are defined as remaining film thicknesses substantially corresponding to remaining film thicknesses that can be formed substantially uniformly corresponding to the concavo-convex pattern other than the concavo-convex pattern. Extracting from the film thickness, and determining the at least one uneven pattern corresponding to the extracted remaining film thickness, each of the plurality of remaining film thicknesses included in the remaining film thickness group, the imprint base of the resin droplet arrangement pattern and the design method of the imprint mold, wherein Rukoto determined based on the size of the basic arrangement pattern is determined according to the concavo-convex pattern Subjected to (invention 8).

Furthermore, the present invention is a method for designing an imprint mold in which a plurality of small regions are arranged in an array in one pattern formation surface, and at least two types of uneven patterns are formed in each small region. And a concavo-convex pattern selecting step of selecting at least one type of concavo-convex pattern from at least two types of concavo-convex patterns to be formed in each small region from a plurality of types of concavo-convex patterns, and within the one small region The concavo-convex pattern arrangement step of arranging each of the at least two types of concavo-convex patterns including the selected concavo-convex pattern selected in the concavo-convex pattern selection step in each of the set at least two pattern formation regions, and the concavo-convex pattern arrangement In the process, each of the at least two pattern formation regions is provided with at least two types of uneven patterns. Said one small region disposed, respectively, wherein and a small region sequence step of arranging a plurality array to one of the pattern formation plane, the concavo-convex pattern selection process, only on the intersection of a given grid line The imprint that spreads wet on the surface to be transferred by bringing the pattern forming surface into contact with the imprint resin that is discretely dropped onto the surface to be transferred by an inkjet method using a resin coating apparatus capable of dripping the imprint resin. Of the concavo-convex pattern structure obtained by curing the resin, it is a remaining film thickness of a portion obtained corresponding to the small region, and is formed substantially uniformly corresponding to each of the plurality of types of concavo-convex patterns. A step of obtaining a remaining film thickness group including a plurality of possible remaining film thicknesses for each of the plurality of types of uneven patterns, and the selected at least two of the at least two types of uneven patterns The remaining film thickness substantially matching the remaining film thickness that can be formed substantially uniformly corresponding to the uneven pattern other than one type of uneven pattern is included in each remaining film thickness group of the plurality of types of uneven patterns. Extracting the plurality of remaining film thicknesses, and determining the at least one uneven pattern corresponding to the extracted remaining film thickness , wherein the plurality of remaining film thicknesses included in the remaining film thickness group are: , respectively, to provide a design method of the imprint mold, wherein Rukoto determined based on the basic arrangement pattern and size of the basic arrangement pattern of the imprint resin droplets is determined according to the uneven pattern (Invention 9 ).

  According to the present invention, the remaining film thickness in the concavo-convex pattern structure can be made substantially uniform as a whole, and it is possible to prevent a decrease in dimensional accuracy of the concavo-convex pattern in the concavo-convex pattern structure and generation of defects. It is possible to provide a method for producing an imprint mold having at least two types of uneven patterns and a method for designing the imprint mold.

FIG. 1 is a plan view showing an example of a pattern forming surface of an imprint mold manufactured by the method of manufacturing an imprint mold according to an embodiment of the present invention. FIG. 2 is a flowchart showing a pattern selection process in the imprint mold manufacturing method according to the embodiment of the present invention. FIG. 3 is a position where an imprint resin can be dropped in an inkjet type resin coating apparatus used in an imprint method using an imprint mold manufactured by an imprint mold manufacturing method according to an embodiment of the present invention. FIG. FIG. 4 shows a method of manufacturing an imprint mold according to an embodiment of the present invention. The type of fine concavo-convex pattern (line and space fine concavo-convex pattern) of the imprint mold, the wet spreading method of the imprint resin, and the basic arrangement It is a top view which shows the relationship with a pattern. FIG. 5 shows a method of manufacturing an imprint mold according to an embodiment of the present invention. The type of fine concavo-convex pattern of the imprint mold (hole-shaped fine concavo-convex pattern), how to spread the imprint resin, and the basic arrangement pattern It is a top view which shows these relationships. FIG. 6 is a table showing an example of the relationship between the main pattern, the basic arrangement pattern, its size, and the remaining film thickness in the imprint mold manufacturing method according to the embodiment of the present invention. FIG. 7 is a table (No. 1) showing an example of a relationship between a dummy pattern candidate (pattern 2), a basic arrangement pattern, its size, and a remaining film thickness in the imprint mold manufacturing method according to an embodiment of the present invention. It is. FIG. 8 is a table (No. 2) showing an example of a relationship between a dummy pattern candidate (Pattern 3), a basic arrangement pattern, its size, and a remaining film thickness in the imprint mold manufacturing method according to an embodiment of the present invention. It is. FIG. 9 is a table (No. 3) showing an example of the relationship between the dummy pattern candidate (pattern 4), the basic arrangement pattern, and the size and the remaining film thickness in the imprint mold manufacturing method according to the embodiment of the present invention. It is. FIG. 10 is a table (No. 4) showing an example of a relationship between a dummy pattern candidate (pattern 5), a basic arrangement pattern, and its size and remaining film thickness in the imprint mold manufacturing method according to an embodiment of the present invention. It is. FIG. 11 shows a pattern (pattern 2) extracted as a dummy pattern candidate that can be formed with a remaining film thickness that substantially matches the remaining film thickness of the main pattern in the imprint mold manufacturing method according to an embodiment of the present invention. -5) is a table showing an example of the basic arrangement pattern and its size, and the remaining film thickness. FIG. 12: is sectional drawing (the 1) which shows the flow of the pattern formation process in the manufacturing method of the imprint mold which concerns on one Embodiment of this invention. FIG. 13: is sectional drawing (the 2) which shows the flow of the pattern formation process in the manufacturing method of the imprint mold which concerns on one Embodiment of this invention. FIG. 14 is a plan view showing another example of the pattern forming surface of the imprint mold manufactured by the method of manufacturing an imprint mold according to the embodiment of the present invention.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing an example of a pattern forming surface of an imprint mold manufactured by the method of manufacturing an imprint mold according to this embodiment, and FIG. 2 is a method of manufacturing the imprint mold according to this embodiment. It is a flowchart which shows the pattern selection process in FIG.

  In the present embodiment, a fine concavo-convex pattern (hereinafter sometimes referred to as “main pattern”) to be transferred to the imprint resin, and the releasability of the imprint mold and filling of the imprint resin into the concave portion of the imprint mold. Two types of fine concavo-convex patterns, which are provided for the purpose of improving the properties and do not need to be originally transferred to the imprint resin (hereinafter sometimes referred to as “dummy patterns”), are formed on the pattern forming surface. A method for producing an imprint mold formed in the above will be described as an example.

  In the imprint mold manufactured in the present embodiment, as shown in FIG. 1, a main pattern (not shown) is formed in a region (main pattern forming region) MA located substantially at the center of the pattern forming surface PS. In addition, dummy patterns (not shown) are formed in four regions (dummy pattern formation regions) DA1 to DA4 located in the pattern formation surface PS and around (mainly) the main pattern formation region MA. An example will be described.

  The method of manufacturing the imprint mold according to the present embodiment is a dummy pattern formed on a pattern formation surface from a plurality of types (two or more types) of fine uneven patterns (hereinafter sometimes referred to as “dummy pattern candidates”). And a pattern forming step of forming the main pattern and the selected dummy pattern in each of the main pattern forming region and the dummy pattern forming region on the base material constituting the imprint mold to be manufactured. Including.

[Dummy pattern selection process]
First, a remaining film thickness group that can be formed substantially uniformly in a fine concavo-convex pattern structure corresponding to a main pattern to be formed on an imprint mold, and a fine concavo-convex pattern corresponding to each of a plurality of types of dummy pattern candidates A remaining film thickness group that can be formed substantially uniformly in the structure is calculated (FIG. 2, S101).

  When an imprint mold manufactured according to this embodiment is used to form a fine concavo-convex pattern structure composed of an imprint resin on a substrate, an inkjet head having a plurality of nozzles arranged in parallel at a predetermined interval is provided. Generally, an imprint resin is discretely dropped on the substrate using a resin coating device.

  In this embodiment, for easy understanding, a general inkjet system in which the inkjet head is fixed so that the parallel direction of the plurality of resin discharge holes (nozzles) is perpendicular to the main scanning direction of the inkjet head. The resin coating apparatus will be described as an example.

The ink jet type resin coating apparatus has limitations on the apparatus that the nozzle interval, the scanning speed of the ink jet head in the main scanning direction, the timing of dropping the imprint resin from the nozzle, and the like cannot always be easily changed. In particular, the dropping timing of the imprint resin can be further limited by a combination of physical properties such as viscosity and surface tension of the imprint resin to be used and the inkjet head to be used. Therefore, as shown in FIG. 3, in the resin coating apparatus, the imprint resin can be dropped only on the intersection PI of the predetermined grid line G. The size (length t ₁ , t _{2 in the} vertical direction (for example, main scanning direction) and the horizontal direction (for example, sub-scanning direction)) of each substantially square cell C configured by the grid lines G is a resin coating device. Are determined according to the nozzle interval, the scanning speed of the inkjet head in the main scanning direction, the timing of dropping the imprint resin from the nozzles, and the like. In particular, the vertical size (length t ₁ in the main scanning direction) of each cell C varies depending on the combination of physical properties such as the viscosity and surface tension of the imprint resin used and the inkjet head used. .

  On the other hand, the imprint resin droplets dropped discretely on the substrate wet and spread when contacting the pattern forming surface of the imprint mold, but not necessarily spread in a substantially circular shape. Depending on the type of fine concavo-convex pattern, wetting and spreading differs. Therefore, for each type of the fine concavo-convex pattern, that is, for each way of imprint resin droplet wetting and spreading, a drop arrangement pattern (basic arrangement pattern) for imprint resin droplets to form a residual film having a uniform thickness. ) Is different.

  In the present embodiment, the basic arrangement pattern is an arrangement pattern of droplets serving as a repeating unit constituting a droplet dropping position of the imprint resin corresponding to each fine concavo-convex pattern, and is a grid line G (FIG. 3) and having an outer shape formed with the intersection formed by the vertexes as the apexes.

  For example, in the case of a line-and-space-shaped fine concavo-convex pattern P, as shown in FIG. 4, the imprint resin droplet D tends to wet and spread along the line direction (longitudinal direction of the fine concavo-convex pattern), and is orthogonal to the line direction. It is hard to spread wet in the direction to do. That is, the droplet D of the imprint resin wets and spreads over a substantially elliptical (or substantially oval) region WA having a major axis along the line direction. The degree of wettability of the imprint resin depends on, for example, the viscosity of the imprint resin, the wettability of the substrate or imprint mold (pattern forming surface), the size of the fine uneven pattern, the depth of the recess, etc. As a result, the size of the substantially elliptical (or substantially oval) region WA in which the droplet D of the imprint resin drops wets is also changed. Therefore, in the case of a line-and-space-shaped fine uneven pattern in which the grid line G (see FIG. 3) and the line direction are substantially parallel, for example, as shown in FIGS. Is a face-centered lattice, simple lattice, or rhombic lattice having an outer shape formed with the intersection point of the grid line G as the apex, depending on the degree of wetting and spreading of the imprint resin (one of the simple square lattices). A shape in which a plurality of imprint resin droplets are arranged along a diagonal line). In particular, in the case of a line-and-space-shaped fine concavo-convex pattern in which the angle between the grid line G (see FIG. 3) and the line direction is about 45 °, as shown in FIG. Depending on the degree of wetting and spreading of the imprint resin, a rhombic lattice shape (a shape in which a plurality of imprint resin droplets are arranged along a diagonal line that is substantially parallel to the orthogonal direction of the line direction among the diagonal lines of a simple square lattice. )

  In the case of the hole-shaped fine concavo-convex pattern P and the pitch of each fine concavo-convex pattern (distance between adjacent fine concavo-convex patterns) is substantially the same, for example, as shown in FIG. D wets and spreads over a substantially circular (radial) area WA. The degree of wettability of the imprint resin depends on, for example, the viscosity of the imprint resin, the wettability of the substrate or imprint mold (pattern forming surface), the size of the fine uneven pattern, the depth of the recess, etc. As a result, the size of the substantially circular area WA in which the droplet D of the imprint resin spreads is also changed. Therefore, in this case, for example, as shown in FIGS. 5A and 5B, the basic arrangement pattern AP has a face-centered lattice shape or a simple lattice shape depending on the degree of wet spread of the imprint resin.

  In addition, the shape, size, and directionality of the area WA where the droplet D of the imprint resin spreads in accordance with the type of the fine concavo-convex pattern (the direction in which the droplet D wets and spreads more easily), and those The types of basic arrangement patterns AP based on the above (the types of face-centered square lattice, square lattice, face-centered rectangular lattice, rectangular lattice, etc.) are experimental using an imprint mold having various fine concavo-convex patterns. Alternatively, it may be obtained by simulation or the like from the structure and dimensions of various fine uneven patterns, the physical properties such as the viscosity of the imprint resin to be used, the wettability of the imprint mold and the substrate surface, and the like.

  For example, an imprint mold in which each of various fine concavo-convex patterns (main pattern, dummy pattern candidate, etc.) (or various fine concavo-convex patterns having the same configuration) is prepared, and a predetermined substrate (to be used) The imprint process is performed by dropping one or a plurality of droplets of imprint resin on a substrate on which a fine concavo-convex pattern structure is to be formed by an imprint process using an imprint mold. As a result, the method of wetting and spreading the imprint resin droplets according to the various fine uneven patterns (the shape, size, and directionality of the droplet spreading area) is determined, and the basics corresponding to the various fine uneven patterns are determined based on this The kind of arrangement pattern can be obtained.

As described above, the size of the basic arrangement pattern AP corresponding to the type of the fine concavo-convex pattern is the size of the cell C formed by the grid lines G determined by the resin coating apparatus used (the vertical direction in FIG. 3 (inkjet It depends on the intervals t ₁ , t ₂ ) of the grid lines G in the main scanning direction of the head) and in the horizontal direction (sub-scanning direction of the inkjet head).

For example, when the basic arrangement pattern AP has the face-centered lattice shape shown in FIGS. 4A and 5A, the size (vertical direction (for example, main scanning direction) and horizontal direction (for example, sub-direction) of the basic arrangement pattern AP. The length T ₁ , T ₂ ) in the scanning direction) is an even multiple of the size of the cell C constituted by the grid lines G. That is, the size of the basic arrangement pattern AP is expressed by the following formulas (1) and (2).
T ₁ = M × (2 × t ₁ ) (1)
T ₂ = N × (2 × t ₂ ) (2)

In addition, when the basic arrangement pattern AP has a simple lattice shape shown in FIGS. 4B and 5B, the size (vertical direction (for example, main scanning direction) and horizontal direction (for example, sub-scanning) of the basic arrangement pattern AP. The lengths T ₁ and T ₂ ) in the direction) are integral multiples of the size of the cell C formed by the grid lines G. That is, the size of the basic arrangement pattern AP is expressed by the following formulas (3) and (4).
T ₁ = M × t ₁ (3)
T ₂ = N × t ₂ (4)

Furthermore, when the basic arrangement pattern AP has an oblique lattice shape shown in FIG. 4C, the size (vertical direction (for example, main scanning direction) and horizontal direction (for example, sub-scanning direction) of the basic arrangement pattern AP. T ₁ , T ₂ ) is a predetermined integer multiple of the size of the cell C formed by the grid lines G (three times in FIG. 4C). That is, the size of the basic arrangement pattern AP is expressed by the following formulas (5) and (6).
T ₁ = M × (3 × t ₁ ) (5)
T ₂ = N × (3 × t ₂ ) (6)
In the formulas (1) to (6), M and N are all integers of 1 or more.

That is, the sizes T1 and T2 of the basic arrangement pattern AP are expressed by the following formulas (7) and (8).
T ₁ = M × V × t ₁ (7)
T ₂ = N × W × t ₂ (8)
In Expressions (7) and (8), M and N are both integers of 1 or more, and the lattice shape of the basic arrangement pattern AP is a shape based on a square lattice (for example, face-centered square lattice, square lattice) M and N are the same (M = N). Further, if the lattice shape is a shape based on a rectangular lattice, either M or N according to the shape of the area WA in which the droplet D of the imprint resin spreads according to the fine uneven pattern of the imprint mold. One becomes larger (M> N or N> M).

  V and W are numbers obtained by adding 1 to the number of droplets of the imprint resin positioned in the lattice shape of the basic arrangement pattern AP. For example, V = W = 1 for a simple lattice, a face-centered lattice If V = W = 2, if it is an orthorhombic lattice, V and W are integers of 3 or more.

  Thus, since the size of the basic arrangement pattern AP depends on the size of the cell C, the remaining film thickness of the fine concavo-convex pattern structure to be formed substantially depends on the type of the fine concavo-convex pattern of the imprint mold. The remaining film thickness when it becomes uniform evenly takes a plurality of values according to the type of the fine uneven pattern and the size of the basic arrangement pattern AP.

  When the type (basic center lattice, simple lattice, orthorhombic lattice, etc.) of the basic arrangement pattern AP is determined according to the type of the fine uneven pattern in the imprint mold, the size of the fine uneven pattern and the depth of the recessed portion are determined. Based on the thickness and area ratio, and the size of the basic arrangement pattern AP, the remaining film thickness that can be formed substantially uniformly in the fine concavo-convex pattern structure can be obtained. Specifically, the remaining film thickness that can be formed substantially uniformly can be obtained by the following equation (9).

Hr = {Dp− (α / 100 × S × Hp)} / S (9)
In the above formula (9), Hr is “residual film thickness that can be formed substantially uniformly (μm)”, Dp is “amount of imprint resin filling the basic arrangement pattern (μm ³ )”, α is “ The area ratio (%) of the concave portions of the fine concavo-convex pattern of the imprint mold, Hp is the “depth of the concave portion of the fine concavo-convex pattern of the imprint mold (μm)”, and S is the area of the basic arrangement pattern (μm ² ) ".

  Therefore, a remaining film thickness group (group consisting of a plurality of remaining film thicknesses determined according to the size of the basic arrangement pattern AP) that can be formed substantially uniformly corresponding to the main pattern by the above formula (9), and dummy pattern candidates It is possible to obtain a remaining film thickness group that can be formed substantially uniformly for each type.

  For example, the main pattern in the imprint mold is a line-and-space fine concavo-convex pattern (in FIG. 6) in which the grid line G (see FIG. 3) in the vertical direction (main scanning direction of the inkjet head) and the line direction are substantially parallel. Pattern 1), where the depth Hp of the recess is 50 nm and the area ratio α of the recess is 50%.

Assuming that the sides t ₁ and t _{2 of the} cell C constituted by the grid lines G are 40 μm and the appropriate amount of the imprint resin is ³ pL (3000 μm ³ ), as shown in FIG. ) And the basic arrangement pattern, the remaining film thickness group that can be formed substantially uniformly can be obtained from the above equation (9).

In addition, the dummy pattern candidate is a line-and-space shape (see pattern 2 and FIG. 7) in which the grid line G (see FIG. 3) in the vertical direction (main scanning direction of the inkjet head) and the line direction are substantially parallel, and in the horizontal direction (see FIG. Line-and-space (pattern 3, see FIG. 8), hole (see pattern 4, see FIG. 9), and grid lines in which the grid line G (see FIG. 3) in the sub-scanning direction of the inkjet head is substantially parallel to the line direction. A line-and-space (pattern 5, see FIG. 10) fine concavo-convex pattern in which the angle formed between G (see FIG. 3) and the line direction is about 45 ° (the line direction is oblique) (grid line G Sides t ₁ and t _{2 of} cell C constituted by: 40 μm, appropriate amount of imprint resin liquid: ³ pL (3000 μm ³ )).

  If the depth Hp of the recess in each dummy pattern candidate (patterns 2 to 5) is 50 nm, each dummy pattern candidate (patterns 2 to 5), the type of each basic arrangement pattern, and the recess Depending on the area ratio α, a remaining film thickness group that can be formed substantially uniformly can be obtained from the above equation (9).

  Note that the value of the area ratio α of the recesses in the dummy pattern candidates is not limited to the values shown in FIGS. 7 to 10, and those values may be set as appropriate as long as the dummy pattern can be formed.

  Next, an arbitrary remaining film thickness is selected from a plurality of remaining film thicknesses included in the remaining film thickness group corresponding to the main pattern (FIG. 2, S102), and the remaining film thickness corresponding to each dummy pattern candidate. A remaining film thickness that substantially matches the remaining film thickness corresponding to the selected main pattern is extracted from the plurality of remaining film thicknesses included in the group (FIG. 2, S103).

  As a method of selecting any one remaining film thickness from among a plurality of remaining film thicknesses included in the remaining film thickness group corresponding to the main pattern, the imprint mold manufactured in the present embodiment is used. It is desirable to select based on the target value of the remaining film thickness in the planned fine uneven pattern structure. In addition, when the fine concavo-convex pattern structure formed on the base material is used as an etching mask for etching the base material in a subsequent process, the target value of the remaining film thickness is as much as possible. A thin film thickness can be set.

  For example, it is assumed that the target value of the remaining film thickness in the fine uneven pattern structure to be formed is 12 nm, and the allowable range of the thickness unevenness is ± 2.0 nm. In this case, among the plurality of remaining film thicknesses (see FIG. 6) included in the remaining film thickness group corresponding to the main pattern, the target value of the remaining film thickness and the allowable range of the thickness unevenness (12 ± 2. The remaining film thickness (12.5 nm) of 0 nm) is selected.

  Then, among the plurality of remaining film thicknesses included in the remaining film thickness group corresponding to each dummy pattern candidate shown in FIGS. 7 to 10, the target value of the remaining film thickness and the allowable thickness unevenness range (12 ± 2). .. 0 nm), and the remaining film thickness substantially matching the selected remaining film thickness (12.5 nm) corresponding to the main pattern is extracted.

  In this embodiment, the criterion for determining whether or not the remaining film thickness corresponding to the dummy pattern candidate substantially matches the remaining film thickness selected from the remaining film thickness group corresponding to the main pattern is the main pattern. Can be set as appropriate according to the remaining film thickness selected from the remaining film thickness group corresponding to. For example, the difference between the remaining film thickness corresponding to the main pattern and the remaining film thickness corresponding to the dummy pattern candidate is preferably 20% or less of the remaining film thickness corresponding to the main pattern, particularly preferably the remaining film thickness corresponding to the main pattern. It can be 10% or less of the film thickness.

  Therefore, as the remaining film thickness corresponding to each dummy pattern candidate substantially corresponding to the remaining film thickness (12.5 nm) corresponding to the selected main pattern, for example, each dummy pattern candidate shown in FIGS. From the corresponding remaining film thickness groups, as shown in FIG. 11, 12.8 nm of pattern 2 (No. 1, recess area ratio α = 33%, basic arrangement 1-1, size: M = 16, N = 4, V = 1, W = 1), 12.5 nm of pattern 2 (No. 2, recess area ratio α = 50%, basic arrangement 1-1, size: M = 10, N = 5, V = 1 , W = 1), 12.8 nm of pattern 3 (No. 3, recess area ratio α = 33%, basic arrangement 1-1, size: M = 4, N = 16, V = 1, W = 1), 12.5 nm of pattern 3 (No. 4, recess area ratio α = 50%, basic arrangement 1-1, size: M 5, N = 10, V = 1, W = 1), 11.0 nm of pattern 4 (No. 5, recess area ratio α = 33%, basic arrangement 2-2, size: M = 6, N = 6 V = 2, W = 2), 13.3 nm of pattern 4 (No. 6, recess area ratio α = 50%, basic arrangement 2-1, size: M = 7, N = 7, V = 1, W = 1), 12.5 nm of pattern 4 (No. 7, recess area ratio α = 50%, basic arrangement 2-2, size: M = 5, N = 5, V = 2, W = 2), pattern 5 12.5 nm (No. 8, recess area ratio α = 25%, basic arrangement 3-1, size: M = 5, N = 5, V = 3, W = 3) and 12.8 nm of pattern 5 (No. 9, the recess area ratio α = 33%, basic arrangement 3-2, size: M = 4, N = 4, V = 4, W = 4) can be extracted.

  Subsequently, on the basis of the remaining film thickness extracted as described above, a dummy pattern to be formed in the dummy pattern formation region on the pattern formation surface of the imprint mold is selected (FIG. 2, S104).

  As shown in FIG. 11, the remaining film thickness corresponding to each of the dummy pattern candidates (patterns 2 to 5) is the remaining film thickness corresponding to the dummy pattern candidate substantially matching the remaining film thickness corresponding to the main pattern. Extracted. Then, a dummy pattern to be formed in the dummy pattern formation region is selected from the dummy pattern candidates corresponding to the extracted remaining film thickness.

  At this time, for example, a dummy pattern candidate having a remaining film thickness with a minimum difference from the remaining film thickness (12.5 nm) corresponding to the main pattern can be selected as a dummy pattern to be formed in the dummy pattern formation region.

  Therefore, if it is above, the pattern (No. 2, 4, 7, 8) which the remaining film thickness which can be formed substantially uniformly is 12.5 nm can be selected as a dummy pattern. By selecting a dummy pattern candidate having the remaining film thickness of the dummy pattern candidate closest to the remaining film thickness corresponding to the main pattern as a dummy pattern, the remaining film in the fine concavo-convex pattern structure formed using the imprint mold The thickness can be made substantially uniform as a whole.

  A plurality of remaining film thicknesses are extracted as the remaining film thickness corresponding to the dummy pattern candidate (residual film thickness substantially matching the remaining film thickness corresponding to the main pattern), and a remaining film thickness group including these remaining film thicknesses is obtained. If there are a plurality of remaining film thickness groups including the remaining film thickness, the remaining film thickness group corresponding to each of two or more types of dummy pattern candidates is included. As a dummy pattern candidate capable of forming a fine concavo-convex pattern structure with a residual film thickness that substantially matches the residual film thickness corresponding to the main pattern, such as when a common residual film thickness included in the film thickness group is extracted) Two or more types of fine uneven patterns may be extracted.

  In this case, the imprint resin droplet wetting and spreading corresponding to the main pattern (the shape and directionality of the droplet WA spreading area WA) and the imprint resin droplet corresponding to each dummy pattern candidate One dummy pattern may be selected from the two or more types of dummy pattern candidates based on the wet spreading method. Specifically, the dummy pattern can be selected so that the shape, direction, and the like of the area WA where the imprint resin droplet wets and spreads between the main pattern and each dummy pattern candidate are approximated. By selecting the dummy pattern in this way, the imprint resin droplet wetting and spreading in the main pattern (droplet flow) and the imprint resin droplet wetting and spreading in the dummy pattern (droplet flow). ), The imprint resin smoothly wets and spreads (flows) in the vicinity of the boundary portion between the main pattern and the dummy pattern, and as a result, the occurrence of defects in the vicinity of the boundary portion is suppressed. be able to.

  As described above, from among dummy pattern candidates (Nos. 1 to 9 in FIG. 11) that substantially match the selected remaining film thickness (12.5 nm) corresponding to the main pattern and can be selected as dummy patterns. Consider a case where one type of dummy pattern candidate is selected as a dummy pattern.

  In this case, the shape of the area WA in which the imprint resin droplets spread out in the main pattern is a substantially elliptical shape or a substantially elliptical shape whose major axis is substantially parallel to the vertical direction (main scanning direction of the inkjet head). In the dummy pattern candidate (pattern 2), the shape of the area WA in which the imprint resin droplets wet and spread is substantially elliptical or substantially parallel to the longitudinal direction (the main scanning direction of the inkjet head) in the same manner as the main pattern. Oval shape. In addition, the shape of the area WA in which the imprint resin droplet wets and spreads in the dummy pattern candidate (pattern 3) is a substantially elliptical shape or a substantially elliptical shape whose major axis is substantially parallel to the horizontal direction (sub-scanning direction of the inkjet head). is there. Furthermore, the shape of the area WA in which the imprint resin droplet wets and spreads in the dummy pattern candidate (pattern 4) is substantially circular. Furthermore, the shape of the area WA in which the imprint resin droplet wets and spreads in the dummy pattern candidate (pattern 5) has a substantially elliptical shape whose major axis is approximately 45 ° with respect to the vertical direction (main scanning direction of the inkjet head). Or it is a substantially oval shape.

  When the shape of the area WA in the four patterns (patterns 2 to 5) is compared with the shape of the area WA in the main pattern, the shape of the area WA in the patterns 2, 3 and 5 and the area WA in the main pattern The shape is common. On the other hand, regarding the directionality of the area WA, the directionality of the area WA in the pattern 2 and the directionality of the area WA in the main pattern are common. Therefore, in this case, the pattern 2 can be selected as the dummy pattern.

  In the above example, since the remaining film thickness corresponding to each of the patterns 2 to 5 is common to 12.5 nm, the imprint resin droplet wetting and spreading corresponding to each fine concavo-convex pattern (liquid The pattern 2 is selected as a dummy pattern based on the shape and direction of the area WA in which the droplet spreads, but the difference between the extracted remaining film thickness and the remaining film thickness corresponding to the main pattern is minimal. If there is only one remaining film thickness, the dummy pattern candidate having the remaining film thickness with the minimum difference may be selected as a dummy pattern.

  Further, when only one remaining film thickness is extracted and there is only one type of dummy pattern corresponding to the remaining film thickness group including the remaining film thickness, it goes without saying that the dummy pattern is formed on the pattern forming surface of the imprint mold. What is necessary is just to select as a dummy pattern formed in a dummy pattern formation area.

  Select the dummy pattern that minimizes the drawing time (electron beam drawing time) for forming the resist pattern image of the dummy pattern in the pattern forming process, which will be described later, if the viewpoint of production efficiency and manufacturing cost of the imprint mold is emphasized May be. For example, in the case of using a positive resist material, a dummy pattern candidate (No. 8, pattern 5, recess area ratio: 25% shown in FIG. 11) having the smallest recess area ratio α may be selected as the dummy pattern. .

  As described above, the dummy pattern is selected based on the remaining film thickness that can be formed substantially uniformly corresponding to the fine uneven pattern scheduled to be formed as the main pattern, and is selected as the main pattern. The imprint mold can be designed (pattern design) by arranging the dummy pattern in each of the main pattern forming region and the dummy pattern forming region on the pattern forming surface. By manufacturing the imprint mold thus designed through a pattern forming process described later, a fine uneven pattern structure having a substantially uniform remaining film thickness as a whole by imprinting using the obtained imprint mold. The body can be formed.

[Pattern formation process]
The main pattern and the dummy pattern selected in the pattern selection step are set on the surface corresponding to the pattern formation surface PS in the base material constituting the imprint mold, and the main pattern formation region MA and the dummy pattern formation regions DA1 to DA1. DA4 is formed.

  First, an electron beam sensitive resist material is applied by spin coating or the like on a surface corresponding to the pattern formation surface PS in the base material 2 constituting the imprint mold 1 to form a resist film 3 (FIG. 12A). 13 (a)), a resist pattern image for forming the main pattern and the dummy pattern is drawn on the main pattern formation area MA and the dummy pattern formation area DA by electron beam irradiation (FIG. 12 (b)). FIG. 13 (b)). 12B and 13B, reference numeral 3a indicates an electron beam irradiation site in the resist film 3, and reference numeral 3b indicates an electron beam non-irradiation site in the resist film 3. In order to form a main pattern and a dummy pattern, the substrate 2 drawn with the electron beam is subjected to a development process using a predetermined developer, a rinse process using a predetermined rinse liquid, and a drying process. The resist pattern 31 is formed (see FIGS. 12C and 13C).

  The base material 2 constituting the imprint mold 1 is not particularly limited, and is a base material commonly used in manufacturing an imprint mold (for example, quartz glass, soda glass, fluorite, Calcium fluoride, silicon substrate, etc.) can be used.

  As the electron beam sensitive resist material, a resist material generally used for electron beam lithography can be used. However, when the main pattern and the dummy pattern are fine convex patterns, a negative resist material is used. (See FIG. 12), and when the main pattern and the dummy pattern are fine concave patterns, it is preferable to use a positive resist material (see FIG. 13).

  In FIG. 12B and FIG. 13B, a resist pattern image may be formed by irradiating ultraviolet rays (UV), lasers, or the like. In this case, a resist applied on the substrate 2 is formed. As a material, a resist material (UV-sensitive resist material, laser-sensitive resist material, etc.) suitable for the type of exposure light source (UV, laser, etc.) may be used.

  Next, the substrate 2 is subjected to a dry etching process using the formed resist pattern 31 as a mask (see FIGS. 12D and 13D). The dry etching method is appropriately selected from known dry etching methods such as reactive gas etching, reactive ion etching, and reactive ion beam etching in consideration of the material of the substrate 2 and the etching gas to be used. For example, when the base material 2 is a silicon substrate or quartz glass, dry etching can be performed by reactive ion etching using a fluorine-based gas. After the dry etching, the imprint mold 1 can be manufactured by removing the remaining resist pattern 31.

  According to the imprint mold manufacturing method according to the present embodiment described above, the fine concavo-convex pattern structure in which the main pattern and the dummy pattern in the imprint mold to be manufactured are obtained by the imprint process using the imprint mold. Is selected so that the overall remaining film thickness can be made substantially uniform as a whole, so that an imprint capable of forming a fine concavo-convex pattern structure having a substantially uniform remaining film thickness as a whole by imprinting A mold can be manufactured.

[Imprint method]
Then, the imprint method using the imprint mold manufactured as mentioned above is demonstrated.

  First, an imprint mold manufactured by the method of manufacturing an imprint mold according to the present embodiment, which is used to form a fine uneven pattern structure on a predetermined substrate (silicon substrate, quartz substrate, etc.) is prepared.

  Next, an imprint resin (a resin (usually used for imprint processing (such as a thermosetting resin or an ultraviolet curable resin))) is dropped onto the substrate in a discrete manner using an ink jet type resin coating apparatus. The dropping position of the imprint resin droplet on the substrate is the basic arrangement pattern AP corresponding to each of the main pattern and the dummy pattern selected in the pattern selection process of the imprint mold manufacturing method according to the present embodiment and its It can be determined based on the size. In addition, as the resin coating apparatus, the resin coating assumed when calculating the remaining film thickness groups in the main pattern and various dummy pattern candidates in the pattern selection step of the imprint mold manufacturing method according to the present embodiment described above. It is preferable to use one having the same configuration as the apparatus.

  Subsequently, an imprint resin dropping arrangement (drop map) is created based on the basic arrangement pattern and the size determined as described above, and the imprint resin is dropped on the substrate according to the drop map.

  Then, the imprint resin dropped discretely at a predetermined position on the substrate is brought into contact with the pattern forming surface of the imprint mold, and the imprint resin is wetted and spread on the substrate. At this time, as described above, the main pattern and the dummy pattern are provided on the pattern forming surface of the imprint mold so that a fine uneven pattern structure having a substantially uniform remaining film thickness can be formed. The imprint resin is dropped based on a drop map in which the remaining film thicknesses of the fine concavo-convex pattern structures formed corresponding to the main pattern and the dummy pattern can be substantially common (matched). Therefore, in that state, the film thickness (residual film thickness) of the concave portions of the fine uneven pattern structure formed by curing the imprint resin becomes substantially uniform as a whole. Therefore, a fine concavo-convex pattern structure having no defect or the like in the fine concavo-convex pattern can be formed.

  Generally, a replica mold manufactured in large quantities through an imprint process using an imprint mold (master mold) manufactured by electron beam lithography or the like as an imprint mold used in a manufacturing process of a wiring pattern of a semiconductor device or the like Is used.

  Therefore, when a replica mold is manufactured using the imprint mold (master mold) manufactured by the imprint mold manufacturing method according to the present embodiment, the substrate is substantially uniform on the base material constituting the replica mold. A fine concavo-convex pattern structure having a residual film thickness and high dimensional accuracy can be formed. Therefore, a highly accurate replica mold can be manufactured by etching the base material using the fine concavo-convex pattern structure as an etching mask.

  In addition, since the dummy pattern formed on the pattern forming surface of the master mold is also accurately transferred to the replica mold together with the main pattern, a substantially uniform residue can be obtained by imprint processing using the replica mold. A fine concavo-convex pattern structure having a high film thickness and high dimensional accuracy can be formed. Therefore, by etching the substrate or the like on which the fine concavo-convex pattern structure is formed, a highly accurate wiring pattern of a semiconductor device or the like can be manufactured.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  In the above embodiment, a predetermined main pattern and one type of dummy pattern are selected accordingly, and they are formed in the main pattern formation region and the dummy pattern formation region on the surface corresponding to the pattern formation surface of the substrate. Although the imprint mold is manufactured by this, this invention is not limited to such an aspect. The present invention can also be applied as a method of manufacturing an imprint mold in which two or more types of main patterns are formed on a pattern forming surface, for example. In this case, a remaining film thickness group that can be formed substantially uniformly corresponding to various fine uneven patterns is calculated, and two or more types of main patterns having a remaining film thickness that substantially matches from the remaining film thickness group. Can be selected.

  In addition, a dummy pattern may be formed in the gap between two or more main patterns in the pattern formation surface of the imprint mold. In this case, the dummy pattern is substantially identical to the two or more selected main patterns. In addition, a dummy pattern capable of forming a fine concavo-convex pattern structure with a uniform residual film thickness can be further selected.

  For example, as shown in FIG. 14, two main pattern formation areas MA1, MA2 and a dummy pattern formation area DA are provided between them in the pattern formation surface PS of the imprint mold. Consider a case where two selected main patterns are formed in each of MA2 and a dummy pattern is formed in the dummy pattern formation area DA. In this case, if the remaining film thickness corresponding to each of the two main patterns is Anm and Bnm (A <B), the dummy pattern can be formed substantially uniformly from the dummy pattern candidates. It is preferable to select a dummy pattern whose remaining film thickness is Cnm (A ≦ C <B, or A <C ≦ B, more preferably A <C <B). The residual film thickness (Cnm) corresponding to the dummy pattern has the above relationship with the residual film thicknesses (Anm and Bnm) corresponding to each of the two main patterns, so that the imprint mold is The uniformity of the remaining film thickness of the fine concavo-convex pattern structure formed by the used imprint process can be further improved.

  In the above embodiment, one type of dummy pattern is selected based on the remaining film thickness that can be formed substantially uniformly corresponding to the main pattern, and one type of dummy pattern selected in the dummy pattern formation areas DA1 to DA5. However, the present invention is not limited to such an embodiment. For example, two or more types of dummy patterns may be selected, and each of the selected two or more types of dummy patterns may be appropriately arranged in each of the dummy pattern formation areas DA1 to DA5.

  Further, the dummy pattern formation areas DA1 to DA5 may be divided into an area close to the main pattern formation areas MA1 and MA2 and a distant area, and different types of dummy patterns may be arranged in the close area and the distant area. . For example, the main pattern is a line-and-space pattern (pattern 1 shown in FIG. 6) in a line direction substantially parallel to the vertical direction (main scanning direction of the ink-jet head), and is used as a dummy pattern in the horizontal direction (second side of the ink-jet head). Assume that a line-and-space pattern (pattern 3 shown in FIG. 8) in the line direction substantially parallel to the scanning direction) is selected. The shapes WA of the imprint resin droplets spreading in the main pattern and the dummy pattern are substantially the same, but the direction of wetting spread is substantially orthogonal. In such a case, the pattern 3 is arranged in a far area in the dummy pattern formation areas DA1 to DA5, and a hole-like pattern (pattern 4 shown in FIG. 9) is arranged in a near area. As a result, the vicinity of the boundary between the main pattern and the dummy pattern (pattern 4) and the boundary between the dummy patterns (pattern 3 and pattern 4) are formed rather than the formation of a dummy pattern perpendicular to the line direction in the vicinity of the main pattern. Since the imprint resin easily wets and spreads (flows) smoothly in the vicinity of the portion, generation of defects at the boundary portion can be suppressed.

  In the above embodiment, a remaining film thickness group corresponding to all of the plural types (four types of patterns 2 to 5) of dummy pattern candidates is obtained, and the remaining film thickness corresponding to the selected main pattern (substantially uniform). The remaining film thickness that substantially matches the remaining film thickness that can be formed) is extracted, and one dummy pattern candidate is selected as a dummy pattern from the extracted remaining film thicknesses. It is not limited to the embodiment. For example, a remaining film thickness group corresponding to one arbitrarily selected dummy pattern candidate among a plurality of types of dummy pattern candidates is obtained, and the remaining film thickness substantially matching the remaining film thickness corresponding to the selected main pattern Is determined to be included in the remaining film thickness group (coincidence determination), and if a substantially matching remaining film thickness is included, the dummy pattern candidate is selected as a dummy pattern. Also good. If the remaining film thickness that substantially matches is not included, the remaining film thickness group is obtained one by one for each of the other types of dummy pattern candidates, and the above matching determination is performed, and the remaining film thickness corresponding to the main pattern is determined. The remaining film thickness group is obtained until it is determined that the remaining film thickness that substantially matches the remaining film thickness is included in the remaining film thickness group.

  In the above embodiment, the target value of the remaining film thickness and the range of the thickness unevenness in the fine uneven pattern structure to be formed are selected from the plurality of remaining film thicknesses included in the remaining film thickness group corresponding to each dummy pattern candidate. The remaining film thickness that is substantially the same as the selected remaining film thickness corresponding to the main pattern is extracted, and the dummy pattern candidate having the remaining film thickness closest to the remaining film thickness corresponding to the main pattern is extracted as the dummy pattern. Have selected as. That is, as the selection criterion for the dummy pattern, the remaining film thickness that can be formed substantially uniformly is set as the first priority criterion. However, the present invention is not limited to such a mode. For example, within the range of the target value of the remaining film thickness and the thickness unevenness among the plurality of remaining film thicknesses included in the remaining film thickness group corresponding to each dummy pattern candidate Extracting the remaining film thickness that substantially matches the selected remaining film thickness corresponding to the main pattern, and from the dummy pattern candidates having such remaining film thickness, how to spread the imprint resin droplets However, a dummy pattern candidate common to the main pattern may be preferentially selected as a dummy pattern. That is, as a reference for selecting a dummy pattern from among the dummy pattern candidates having the remaining film thickness extracted as described above, whether or not the wet pattern of the imprint resin droplets is shared with the main pattern is determined. One priority criterion may be used, and when there are a plurality of dummy pattern candidates that share the same imprint resin droplet wetting and main pattern with the main pattern, the dummy pattern may be selected based on the remaining film thickness.

  In the above embodiment, as shown in FIG. 1, a main pattern (not shown) is formed in a region (main pattern formation region) MA located substantially at the center of the pattern formation surface PS, and is within the pattern formation surface PS. The selected dummy pattern (not shown) is formed in four areas (dummy pattern formation areas) DA1 to DA4 located around (four sides) of the main pattern formation area MA. It is not limited to such an aspect. For example, the present invention can also be applied to a method of manufacturing or designing an imprint mold in which one type of main pattern is arranged in a plurality of arrays in the pattern formation surface PS.

  In this case, the small areas including the main pattern forming area MA and the dummy pattern forming areas DA1 to DA4 as shown in FIG. 1 are set so as to be arranged in a plurality of arrays in the pattern forming surface PS.

  Next, assuming that one small region is the pattern formation surface PS, a dummy pattern (in the dummy pattern formation regions DA1 to DA4) corresponding to the main pattern to be formed in the main pattern formation region MA is obtained in the same manner as in the above-described embodiment. Dummy pattern to be formed) is selected.

  Then, the main pattern and the selected dummy pattern are arranged in each of the areas MA and DA1 to DA4 in one small area. Finally, the one small region is arranged in a plurality of arrays in the pattern forming surface PS.

  Of the fine concavo-convex pattern structure formed using such an imprint mold, the remaining film thickness is substantially uniform in at least the portion formed corresponding to the main pattern and the dummy pattern in the one small region. Therefore, by using an imprint mold in which the small regions are arranged in a plurality of arrays in the pattern formation surface PS, it becomes possible to form a fine uneven pattern structure having a substantially uniform remaining film thickness as a whole. .

  Therefore, when manufacturing or designing an imprint mold in which one type of main pattern is arranged in a plurality of arrays in the pattern forming surface PS, a plurality of small regions arranged in the array in the pattern forming surface PS. Since the dummy pattern corresponding to the main pattern is designed in one of the small areas, and the small area is expanded in the pattern forming surface PS, the entire imprint mold can be designed. The dummy pattern can be easily designed.

  Similarly, the present invention can also be applied to a method for manufacturing or designing an imprint mold in which two or more kinds of main patterns are arranged in a plurality of arrays in the pattern forming surface PS.

  In this case, the small areas including the main pattern formation areas MA1 and MA2 and the dummy pattern formation areas DA1 to DA5 as shown in FIG. 14 are set so as to be arranged in a plurality of arrays on the pattern formation surface PS.

  Next, assuming that one small region is the pattern formation surface PS, a dummy pattern (dummy pattern formation region) corresponding to the main pattern to be formed in each of the main pattern formation regions MA1 and MA2 in the same manner as the above-described embodiment. Dummy patterns formed on DA1 to DA5) are selected.

  Then, the main pattern and the selected dummy pattern are arranged in each of the areas MA1, MA2, DA1 to DA5 in one small area. Finally, the one small region is arranged in a plurality of arrays in the pattern forming surface PS.

  As a result, a small region including a plurality of types of main patterns can be used as one design target unit, and the entire imprint mold can be designed by expanding the small region within the pattern forming surface PS. The dummy pattern in the imprint mold can be easily designed.

  The present invention is useful for manufacturing an imprint mold used in a nanoimprint process for forming a fine concavo-convex pattern in a manufacturing process of a semiconductor device or the like.

DESCRIPTION OF SYMBOLS 1 ... Imprint mold 2 ... Base material PS ... Pattern formation surface MA ... Main pattern formation area (pattern formation area)
DA: Dummy pattern formation area (pattern formation area)

Claims (9)

A method for producing an imprint mold in which at least two types of concavo-convex patterns are formed on a pattern forming surface,
A concavo-convex pattern selection step of selecting at least one concavo-convex pattern among at least two types of concavo-convex patterns formed on the pattern forming surface from a plurality of types of concavo-convex patterns;
Each of at least two pattern formation regions arranged in a plane corresponding to the pattern formation surface on the substrate constituting the imprint mold includes the selected uneven pattern selected in the uneven pattern selection step. A concavo-convex pattern forming step of forming each of the at least two types of concavo-convex patterns,
The uneven pattern selection step includes :
Using a resin coating apparatus capable of dropping imprint resin only on the intersections of predetermined grid lines, the imprint resin that is discretely dropped onto the transfer surface by the inkjet method is brought into contact with the pattern forming surface of the imprint mold. This is the remaining film thickness of the uneven pattern structure obtained by curing the imprint resin wetted and spread in the transferred surface, and is formed substantially uniformly corresponding to each of the plurality of types of uneven patterns. Obtaining a remaining film thickness group including a plurality of possible remaining film thicknesses for each of the plurality of types of uneven patterns;
Of the at least two types of concavo-convex patterns, the residual film thickness substantially corresponding to the residual film thickness that can be formed substantially uniformly corresponding to the concavo-convex pattern other than the selected at least one type of concavo-convex pattern, Extracting from the plurality of remaining film thicknesses included in the respective remaining film thickness groups of the plurality of types of uneven film patterns, and determining the at least one uneven film pattern corresponding to the extracted remaining film thicknesses ;
Including
A plurality of residual film thickness contained in the residual film Atsugun, respectively, that are determined based on the size of the basic arrangement pattern and the basic arrangement pattern of the imprint resin droplets is determined according to the uneven pattern An imprint mold manufacturing method characterized by the above. In the uneven pattern selection step,
Remaining film thicknesses that can be formed substantially uniformly corresponding to each of the at least two types of concavo-convex patterns substantially match each other, and are substantially uniform corresponding to each of the at least two types of concavo-convex patterns. The at least one type of concavo-convex pattern is selected so that the dropping arrangement of the imprint resin on the transfer surface related to each remaining film thickness that can be formed is similar to each other. The manufacturing method of the imprint mold of 1 . The imprint mold is formed by forming at least three types of uneven patterns on the pattern forming surface,
Irregularities in at least three patterns forming region arranged on the pattern forming surface corresponding to the plane on on the substrate constituting the imprint mold, determines the position of each of which is formed of at least three kinds of the uneven pattern A pattern forming position determining step,
In the uneven pattern formation position determining step,
The remaining film thickness that can be substantially formed corresponding to the concave / convex pattern formed in one pattern formation region of the at least three pattern formation regions, and another pattern formation region adjacent to the one pattern formation region The at least three types of concavo-convex patterns of the at least three types of concavo-convex patterns so that the difference from the remaining film thickness that can be formed substantially uniformly corresponding to the concavo-convex pattern formed in the region adjacent to the one pattern forming region method for manufacturing an imprint mold according to claim 1 or 2, characterized in that to determine the position where each is formed. An auxiliary concavo-convex pattern selecting step for selecting an auxiliary concavo-convex pattern for assisting imprint processing using the imprint mold, which is formed in a gap between two adjacent pattern formation regions;
In the auxiliary concavo-convex pattern selection step,
Each of the two types of concavo-convex patterns formed in each of the two adjacent pattern forming regions substantially corresponds to each remaining film thickness that can be formed substantially uniformly and is substantially uniform. Select the auxiliary concavo-convex pattern that can form the concavo-convex pattern structure of the remaining film thickness,
In the uneven pattern forming step,
Each of the two types of concavo-convex patterns including the selected concavo- convex pattern selected in the concavo-convex pattern selection step is formed in each of the two adjacent pattern forming regions, and the selected auxiliary concavo-convex pattern is adjacent to the adjacent concavo-convex pattern. imprint mold manufacturing method according to any one of claims 1 to 3, characterized in that formed on the two gaps of the pattern forming region. The remaining film thickness that can be formed substantially uniformly corresponding to the concavo-convex pattern is calculated by the following formula based on the basic arrangement pattern of the droplets of the imprint resin and the size of the basic arrangement pattern. The manufacturing method of the imprint mold in any one of Claims 1-4 .
Hr = {Dp− (α / 100 × S × Hp)} / S
In the formula, Hr is “residual film thickness (μm) having a substantially uniform thickness”, Dp is “amount of imprint resin filling the basic arrangement pattern (μm ³ )”, α is “mold uneven pattern” Hp represents “the depth (μm) of the concave portion of the concave / convex pattern of the mold”, and S represents “the area of the basic arrangement pattern (μm ² )”. Claim 1-5 wherein at least one of the uneven pattern of the at least two kinds of concave-convex pattern, wherein the a main pattern to be transferred in the imprint mold uneven pattern structure obtained by using a The manufacturing method of the imprint mold in any one of. The at least one type of concavo-convex pattern selected in the concavo-convex pattern selection step is a dummy pattern for assisting peeling of the imprint mold in the imprint process using the imprint mold. The manufacturing method of the imprint mold in any one of 1-6 . A method of designing an imprint mold in which at least two types of uneven patterns are formed on a pattern forming surface,
A concavo-convex pattern selection step of selecting at least one concavo-convex pattern among at least two types of concavo-convex patterns formed on the pattern formation surface from a plurality of types of concavo-convex patterns;
The uneven pattern selection step includes :
Using a resin coating apparatus capable of dropping imprint resin only on the intersections of predetermined grid lines, the imprint resin that is discretely dropped onto the transfer surface by the inkjet method is brought into contact with the pattern forming surface of the imprint mold. This is the remaining film thickness of the uneven pattern structure obtained by curing the imprint resin wetted and spread in the transferred surface, and is formed substantially uniformly corresponding to each of the plurality of types of uneven patterns. Obtaining a remaining film thickness group including a plurality of possible remaining film thicknesses for each of the plurality of types of uneven patterns;
Of the at least two types of concavo-convex patterns, the residual film thickness substantially corresponding to the residual film thickness that can be formed substantially uniformly corresponding to the concavo-convex pattern other than the selected at least one type of concavo-convex pattern, Extracting from the plurality of remaining film thicknesses included in the respective remaining film thickness groups of the plurality of types of uneven film patterns, and determining the at least one uneven film pattern corresponding to the extracted remaining film thicknesses ;
Including
A plurality of residual film thickness contained in the residual film Atsugun, respectively, that are determined based on the size of the basic arrangement pattern and the basic arrangement pattern of the imprint resin droplets is determined according to the uneven pattern A method for designing an imprint mold. A method of designing an imprint mold in which a plurality of small regions are arranged in an array in one pattern forming surface, and at least two types of uneven patterns are formed in each small region,
A concavo-convex pattern selection step of selecting at least one concavo-convex pattern among at least two types of concavo-convex patterns formed in each small region from a plurality of types of concavo-convex patterns;
A concavo-convex pattern arrangement in which each of the at least two types of concavo-convex patterns including the selected concavo-convex pattern selected in the concavo-convex pattern selection step is arranged in each of at least two pattern formation regions set in one small region Process,
The one small region in which each of the at least two types of uneven patterns is disposed in each of the at least two pattern forming regions in the uneven pattern arranging step is arranged in a plurality of arrays within the one pattern forming surface. Including a small region arrangement step,
The uneven pattern selection step includes :
Using a resin coating apparatus capable of dropping imprint resin only on intersections of predetermined grid lines, the imprint resin that is discretely dropped onto the transfer surface by the inkjet method and the pattern forming surface are brought into contact with each other. Of the concavo-convex pattern structure obtained by curing the imprint resin spreading on the transfer surface, the remaining film thickness of the portion obtained corresponding to the small region, each of the plurality of types of concavo-convex patterns A step of obtaining a remaining film thickness group including a plurality of remaining film thicknesses that can be formed substantially uniformly corresponding to the plurality of types of uneven patterns,
Of the at least two types of concavo-convex patterns, the residual film thickness substantially corresponding to the residual film thickness that can be formed substantially uniformly corresponding to the concavo-convex pattern other than the selected at least one type of concavo-convex pattern, Extracting from the plurality of remaining film thicknesses included in the respective remaining film thickness groups of the plurality of types of uneven film patterns, and determining the at least one uneven film pattern corresponding to the extracted remaining film thicknesses ;
Including
A plurality of residual film thickness contained in the residual film Atsugun, respectively, that are determined based on the size of the basic arrangement pattern and the basic arrangement pattern of the imprint resin droplets is determined according to the uneven pattern A method for designing an imprint mold.

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