JP2016009798A - Imprint method and imprint device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imprint method and imprint device that can prevent occurrence of a pattern defect caused by the difference in wet-spreading of droplets of imprint resin in imprint processing.SOLUTION: An imprint method for transferring a fine uneven pattern onto imprint resin supplied discretely on a transfer target substrate according to an ink jetting method by using an imprint mold containing areas having at least two different types of surface shapes in a pattern area at the principal surface side of a substrate calculates the supply amount and number of droplets of imprint resin onto the transfer target substrate, determines a wet-spreading scheduled region of droplets when the pattern region is brought into contact with the droplets supplied onto the transfer target substrate, determines the supply position of the imprint resin on the basis of the number of the droplets and the wet-spreading scheduled region, supplies the imprint resin onto the transfer target substrate on the basis of the supply position, and brings the fine uneven pattern into contact with the droplets at a wet-spreading timing at which the droplets wets and spreads in the wet-spreading scheduled region.

Description

  The present invention relates to an imprint method and an imprint apparatus using 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 has attracted attention in its manufacturing process and the like.

  In the nanoimprint technology, generally, an imprint resin as a workpiece is applied on a substrate to be transferred, and the imprint resin is cured while the imprint resin and the imprint mold are in contact with each other, thereby imprinting the imprint resin. A fine concavo-convex pattern structure formed by transferring the fine concavo-convex pattern of the mold is formed. Further, by performing the etching process on the transfer substrate using the fine uneven pattern structure thus formed as a mask, the fine uneven pattern of the imprint mold can be transferred to the transfer substrate.

  As a method for applying the imprint resin onto the transfer substrate, an ink jet method in which the imprint resin is discretely dropped on the transfer substrate in a predetermined arrangement is known. The imprint resin that is discretely dropped onto the substrate surface by the ink jet method comes into contact with the fine concavo-convex pattern in the imprint mold, and the capillary force due to the fine concavo-convex pattern mainly wets and spreads on the surface of the transferred substrate. Therefore, when the imprint resin is dropped onto the transfer substrate by the ink jet method, the imprint resin droplets wet and spread are imprinted so that pattern defects do not occur in the fine uneven pattern structure. The dripping arrangement of the print resin needs to be determined.

US Pat. No. 5,772,905

  Pattern defects in the imprint process may occur even if the imprint resin dropping position is appropriate. For example, an imprint mold having one pattern region and two kinds of fine concavo-convex patterns (a first fine concavo-convex pattern and a second fine concavo-convex pattern) having different pattern structures formed in the pattern region is used. Consider the case where the imprint process is performed. In this imprint process, the imprint resin droplets in contact with the first fine concavo-convex pattern and the imprint resin droplets in contact with the second fine concavo-convex pattern are wet spread on the transfer substrate. Different. Then, in the vicinity of the boundary portion between the first fine concavo-convex pattern and the second fine concavo-convex pattern, liquid droplets having different wetting and spreading methods come into contact with each other, thereby generating a pattern defect in the vicinity of the boundary portion. That is, when imprint resin droplets come into contact during imprint processing (transfer), there are multiple shapes (structures) in the surface of the imprint mold that differ in how the droplets spread out. However, there is a problem in that a pattern defect occurs due to a difference in the wet spread of the imprint resin droplets.

  In view of the above problems, the present invention provides an imprint method and an imprint apparatus that can prevent the occurrence of pattern defects due to the difference in the wet spread of imprint resin droplets during imprint processing. For the purpose.

  In order to solve the above problems, the present invention provides an imprint mold in which a fine uneven pattern is formed in a pattern region on the main surface side of a substrate, and the pattern region includes at least two types of regions having different surface shapes. A method for transferring the fine concavo-convex pattern onto an imprint resin that is discretely supplied onto the substrate to be transferred by an inkjet method, and supplying the imprint resin supplied onto the substrate to be transferred A step of determining an amount, a step of calculating the number of droplets of the imprint resin supplied on the transfer substrate based on a supply amount of the imprint resin, and a supply of the imprint resin on the transfer substrate When the pattern area of the imprint mold is brought into contact with the droplet of the imprint resin, the droplet will spread on the transfer substrate. A position for obtaining the imprint resin is determined on the substrate to be transferred based on the step of obtaining the region, the number of droplets of the imprint resin, and the region where the droplets are expected to spread on the substrate to be transferred. A step of supplying the imprint resin onto the substrate to be transferred based on a supply position of the imprint resin, and a region where the droplets of the imprint resin are to spread on the substrate to be transferred. And a step of bringing the fine concavo-convex pattern of the imprint mold into contact with droplets of the imprint resin on the substrate to be transferred at a timing when the substrate is wet and spread (Invention 1). ).

  In the present invention, the “surface shape” means the shape of the surface of the region that is in direct contact with the droplets of the imprint resin in the step of transferring the fine uneven pattern to the imprint resin. The “regions having two different surface shapes” mean two regions in which the shapes of regions where the imprint resin droplets are expected to spread out are different from each other. As a case where two types of regions having different surface shapes exist, for example, when a fine concavo-convex pattern having a different pattern structure such as a line-and-space shape or a hole shape is formed in one pattern region, The case where the area | region formed and the area | region in which the fine uneven | corrugated pattern is not formed exist in one pattern area | region etc. are mentioned.

  When the droplets of the imprint resin supplied discretely on the transfer substrate come into contact with the pattern region of the imprint mold, the droplets spread out in a predetermined region depending on the surface shape of the pattern region. For example, when the surface shape of the pattern region, that is, the fine concavo-convex pattern formed in the pattern region is a line-and-space shape, the droplet contacting the region in which the fine concavo-convex pattern is formed moves in the line direction (space (Direction) is substantially spread in a substantially oval shape (elliptical shape) having a major axis. On the other hand, when the fine concavo-convex pattern formed in the pattern region has a hole shape, or when there is a region in which the fine concavo-convex pattern is not formed in the pattern region, the region in which the hole-shaped fine concavo-convex pattern is formed or the minute A droplet that comes into contact with a region where the uneven pattern is not formed spreads in a substantially circular shape. As described above, when the imprint mold pattern region includes regions having different shapes in which the droplet wets and spreads when coming into contact with the droplet, a defect in the transfer pattern is likely to occur at the boundary portion between these regions. . However, according to the above invention (Invention 1), for each region having a different surface shape, which is included in the pattern region of the imprint mold, the region where the droplet is expected to spread when the region contacts the droplet The imprint resin supply position is determined on the basis of the area to be spread and spread, so that an appropriate transfer timing can be determined for each imprint process, and the occurrence of defects due to the imprint process can be prevented. .

  In the above invention (Invention 1), the region where the droplets are scheduled to spread on the substrate to be transferred includes the diameter in plan view of the droplets of the imprint resin supplied on the substrate to be transferred, and the fine irregularities It is preferable to be obtained based on the pattern structure of the pattern (Invention 2).

  In the above invention (Invention 2), it is preferable that a plane view diameter of the droplet of the imprint resin is a maximum diameter in a plan view of the droplet of the imprint resin supplied on the transfer target substrate (Invention). 3).

  In the above inventions (Inventions 1 to 3), the state of the droplets of the imprint resin supplied onto the substrate to be transferred is observed, and the droplets of the imprint resin are scheduled to spread on the substrate to be transferred. It is preferable to determine the timing of spreading in the region (Invention 4).

  In the above invention (invention 4), the state of the droplets of the imprint resin on the one surface of the transferred substrate is observed from the other surface side facing the one surface of the transferred substrate through the transferred substrate. (Invention 5) The state of droplets of the imprint resin on the one surface of the transferred substrate through the imprint mold disposed to face the one surface of the transferred substrate May be observed (Invention 6).

  In the above inventions (Inventions 4 to 6), a time for observing the state of the imprint resin droplets supplied onto the transfer substrate is defined in advance, and the imprint resin droplets are observed within the observation time. It is preferable that the fine uneven pattern of the imprint mold is brought into contact with the droplets of the imprint resin on the substrate to be transferred when the state becomes a state where the region can be wet spread. 7).

  Further, the present invention uses an imprint mold in which a fine uneven pattern is formed in a pattern region on the main surface side of a substrate, and the pattern region includes at least two types of regions having different surface shapes. An imprint apparatus for transferring the fine concavo-convex pattern to an imprint resin supplied on the resin, wherein a resin application unit discretely supplies the imprint resin onto the transfer substrate by an inkjet method, and the transfer target When the pattern region of the imprint mold is brought into contact with the droplet of the imprint resin supplied on the substrate, the timing at which the droplet spreads to the region where the droplet is expected to spread on the transferred substrate is determined. The transfer timing determination unit and the transfer timing determination unit at the timing determined by the transfer timing determination unit. Providing an imprinting apparatus characterized by comprising said droplets of preparative resin imprint the transfer portion contacting a fine concavo-convex pattern of the mold (invention 8).

  ADVANTAGE OF THE INVENTION According to this invention, the imprint method and imprint apparatus which can prevent generation | occurrence | production of the pattern defect resulting from the difference in the wet spreading method of the droplet of the imprint resin at the time of an imprint process can be provided.

FIG. 1 is a flowchart showing each step of an imprint method according to an embodiment of the present invention. FIG. 2 is a cut end view schematically showing an aspect of an imprint mold used in the imprint method according to the embodiment of the present invention. FIG. 3 is a plan view schematically showing the configuration of the pattern area of the imprint mold used in the imprint method according to the embodiment of the present invention. FIG. 4 is a plan view schematically showing a region where the imprint resin droplets spread out in the imprint method according to the embodiment of the present invention. FIG. 5 is a graph showing the relationship between the elapsed time after the droplet of imprint resin is dropped (supplied) and the diameter of the droplet in the imprint method according to an embodiment of the present invention. FIG. 6 is a schematic configuration diagram illustrating an imprint apparatus according to an embodiment of the present invention.

Embodiments of the present invention will be described with reference to the drawings.
[Imprint method]
FIG. 1 is a flowchart showing each step of the imprint method according to the present embodiment.
In the imprint method according to the present embodiment, imprint patterns 12a and 12b are formed in the pattern area Pa on the main surface 11a side of the substrate 11 (on the side facing the transfer target substrate during imprint processing). An imprint that is prepared by preparing a print mold 10 (see FIG. 2) and a substrate to be transferred on which a fine concavo-convex pattern structure composed of an imprint resin is formed, and is dropped and supplied onto the substrate to be transferred. The amount of resin supplied is determined (S101). In the present embodiment, as shown in FIG. 2, the imprint mold 10 has a convex structure portion 13 protruding from the main surface 11 a side of the base material 11, and the entire upper surface 13 a of the convex structure portion 13 is formed. A pattern region Pa in which fine concave and convex patterns 12a and 12b are formed on the upper surface 13a (pattern region Pa) and a depression 14 is formed on the back surface 11b side facing the main surface 11a of the substrate 11. An example will be described, but the present invention is not limited to such an embodiment.

  As a base material which comprises the imprint mold 10, as long as it is a base material normally used as a base material for imprint molds, there is no restriction | limiting in particular. For example, a quartz glass substrate, a soda glass substrate, a calcium fluoride substrate, a magnesium fluoride substrate, an acrylic glass, etc., a laminated substrate formed by laminating two or more substrates selected from these, a silicon substrate, Examples thereof include semiconductor substrates such as gallium nitride substrates; metal substrates such as nickel substrates, titanium substrates, and aluminum substrates.

  As a substrate to be transferred, for example, a quartz glass substrate, a soda glass substrate, a calcium fluoride substrate, a magnesium fluoride substrate, an acrylic glass, or the like, or a laminate formed by laminating two or more substrates arbitrarily selected from these Examples include substrates such as silicon substrates, semiconductor substrates such as gallium nitride substrates, and metal substrates such as nickel substrates, titanium substrates, and aluminum substrates.

  As will be described later, in the imprint method according to the present embodiment, the image of the imprint resin droplets dropped on the transfer substrate is imaged and observed from the lower side of the transfer substrate by the imaging unit, and transferred. Determine the timing (see FIG. 6). Therefore, the substrate to be transferred is preferably a base material that can transmit imaging light.

  In the present embodiment, “transmittable” means that imaging light can be transmitted to such an extent that an image necessary for observing the imprint resin droplets can be captured. For example, “transmittable” means that when the above-described image is captured using a visible light camera, the transmittance of light with a wavelength of 380 to 810 nm is 50% or more, preferably 80% or more. When the above-mentioned image is picked up using, it means that the transmittance of light having a wavelength of 1 μm or more is 50% or more, preferably 80% or more.

  The supply amount of the imprint resin can be calculated as the amount of the imprint resin necessary for forming the fine uneven pattern structure on the substrate to be transferred. For example, as shown by the following formula, the fine uneven pattern of the imprint mold 10 is calculated by multiplying the product of the planar view area of the fine uneven pattern structure formed on the transfer substrate and the preset remaining film thickness. By adding the volumes of the recesses 12a and 12b, the supply amount of the imprint resin can be calculated.

S = A × T + V
In the above formula, S is “amount of imprint resin supplied”, A is “a plan view area of the fine uneven pattern structure (a plan view area of the pattern area Pa of the imprint mold 10)”, and T is “the remaining film” “Thickness” and V represent “the total volume of the concave portions of the fine uneven patterns 12a and 12b of the imprint mold 10”.

  As will be described later, in the actual imprint process, the imprint resin volatilizes and decreases in volume from when the imprint resin is dropped (supplied) onto the transfer substrate until the imprint process is started. Occurs. Therefore, as the supply amount of the imprint resin, the supply amount of the imprint resin may be calculated in consideration of the volume reduction amount.

  Next, the number of imprint resin droplets (integer) supplied onto the transfer substrate is determined from the calculated supply amount of the imprint resin (S102). The number of imprint resin droplets is the amount of the imprint resin supply S calculated as described above, which is the amount of one droplet dropped from the inkjet nozzle of the inkjet apparatus used in the imprint method according to this embodiment. It can be determined by dividing. When the supply amount S of the imprint resin is not divisible by the drop amount, for example, the number of droplets of the imprint resin is calculated by rounding up the first decimal place of the numerical value obtained by dividing the supply amount S by the drop amount. What is necessary is just to calculate.

  Subsequently, when the imprint resin droplets dropped on the transferred substrate come into contact with the fine concavo-convex patterns 12a and 12b of the imprint mold 10, the region is considered to spread wet on the transferred substrate (scheduled to spread). (Region) is determined (S103).

  In the pattern area Pa of the imprint mold 10 in the present embodiment, there are at least two areas having different surface shapes. For example, as shown in FIG. 3, a line-and-space fine concavo-convex pattern 12a is formed in the first region Pa1 in the pattern region Pa of the imprint mold, and a hole shape is formed in the second region Pa2. It is assumed that the fine uneven pattern 12b is formed.

  In this case, as shown in FIG. 4A, the imprint resin droplet 20a in contact with the line-and-space-shaped fine unevenness pattern 12a formed in the first region Pa1 is in the line direction (space direction). , Y direction in FIG. 4A) spreads in a substantially oval region 21a having a major axis. On the other hand, as shown in FIG. 4B, the imprint resin droplet 20b that is in contact with the hole-shaped fine concavo-convex pattern 12b formed in the second region Pa2 has a substantially circular shape. The region 21b is wet and spreads.

  As described above, the shapes of the regions 21a and 21b where the imprint resin droplets 20a and 20b spread out are different depending on the surface shape of the pattern region Pa of the imprint mold 10 with which the imprint resin droplets come into contact. In the vicinity of the boundary between the first region Pa1 and the second region Pa2 having different surface shapes, droplets having different shapes of the wet-spread regions 21a and 21b come into contact with each other. At this time, liquid droplets having different shapes in the wet-spreading areas come into contact with each other, so that the imprint resin is not filled in the concave portions of the fine concavo-convex pattern, and voids are easily generated, and the voids cure the imprint resin. In some cases, it does not disappear before it remains. This is considered to be due to the fact that the droplets having different shapes in the wet-spreading areas come into contact with each other, whereby the flow of the liquid droplets (flow to the area that is scheduled to spread wet) fluctuates. Therefore, a pattern defect may occur in the vicinity of the boundary between the first region Pa1 and the second region Pa2. Therefore, in order to prevent the occurrence of pattern defects, it is important to determine the arrangement of the imprint resin droplets in consideration of the wetted and spread expected area of each droplet.

  On the other hand, the shape of the region 21a where the droplets that come into contact with the line-and-space-shaped fine concavo-convex pattern 12a spread out varies depending on the timing at which the imprint mold 10 and the imprint resin droplets 20a contact each other. For example, when the line-and-space fine concavo-convex pattern 12a is in contact with the imprint resin droplet 20a immediately after dropping (FIG. 4A), a predetermined time has elapsed since the dropping, and the droplet In the case of contact with the imprint resin droplet 20c ′ having a larger diameter of 20c (FIG. 4C), the latter (FIG. 4C) is more wet with the region 21c having a more circular shape. spread. That is, the ratio of the major axis to the minor axis of the former wetting and spreading region 21a is larger than the ratio of the latter wetting and spreading region. This is because the imprint resin droplets gradually increase in diameter immediately after being dropped on the substrate to be transferred, and the larger the droplet diameter, the more wetting and spreading in a region closer to a circular shape.

  Even when there are at least two types of regions Pa1 and Pa2 having different surface shapes in the pattern region Pa of the imprint mold 10 and droplets having different shapes in the regions spreading wet with each other are in contact with each other, If the shape of the wet spreading region is a more approximate shape, pattern defects are less likely to occur. As in the above example, the line-and-space-shaped fine unevenness pattern 12a is formed in the first region Pa1 of the pattern region Pa of the imprint mold 10, and the hole-shaped fine unevenness is formed in the second region Pa2. In the case where the pattern 12b is formed, the droplet 20a that contacts the line-and-space fine uneven pattern 12a spreads in a more circular area (for example, in the area 21c shown in FIG. 4C). By performing the imprint process (so that it spreads wet), the occurrence of pattern defects can be suppressed.

  Therefore, in the present embodiment, the shapes of the regions where the imprint resin droplets spread out in contact with each of the plurality of regions (the first region Pa1 and the second region Pa2) having different surface shapes are approximate to each other. The area where each droplet is scheduled to spread is determined so as to obtain the shape to be formed. That is, the transfer timing at which the pattern area Pa of the imprint mold 10 and the imprint resin droplet are brought into contact with each other (after the droplet of the imprint resin is dropped on the transfer substrate, the pattern area Pa of the imprint mold 10 is liquidized. Time until contact with a droplet) and a region where each droplet is expected to spread out at the transfer timing is obtained.

When the imprint resin droplet is brought into contact with each of a plurality of regions having different surface shapes, the imprint resin droplet dropped onto the transfer substrate is imprinted on the droplet at the timing when the maximum diameter R _MAX is reached. If the pattern area Pa of the print mold 10 can be brought into contact with each other, the shape of the area where the imprint resin droplets spread out becomes a shape similar to each other.

On the other hand, since the imprint resin may contain a component that easily volatilizes (volatile component), the imprint resin waits until the droplet of the imprint resin dropped on the transfer substrate reaches the maximum diameter R _MAX. When the treatment is performed, the component composition of the imprint resin changes due to volatilization, which adversely affects the function as an imprint resin such as curability and etching resistance, and the volume of the imprint resin decreases. There is a risk of causing defects (unfilled defects due to insufficient imprint resin). Therefore, within the allowable range of the amount of volatilization of the imprint resin (time after the droplet of the imprint resin is dropped), taking into account the change in the composition ratio due to volatilization of the imprint resin, volume reduction, etc. It is necessary to obtain a transfer timing at which the diameter of the imprint resin droplet becomes maximum.

In other words, even if the composition ratio changes due to the volatilization of the imprint resin droplets dropped on the substrate to be transferred, it does not cause defects due to volume reduction while functioning sufficiently as an imprint resin. The time (maximum diameter of the droplet at that time is referred to as “R _INP ”) during which the droplet diameter becomes the maximum within (the time after the imprint resin droplet is dropped) is obtained in advance. The time is preferably determined as the transfer timing for starting the imprint process in the present embodiment.

The transfer timing for starting the imprint process can be obtained as follows, for example.
First, a droplet of an imprint resin is dropped on a substrate to be transferred, and the state of the droplet being naturally wet and spread is observed from above or below the droplet, and the droplet corresponds to the passage of time after dropping. Measure the change in diameter. It is preferable to observe the droplets in an atmosphere similar to the atmosphere in the actual imprint process. In other words, it is preferable to observe a plurality of droplets dropped on the substrate to be transferred in the imprint apparatus. The arrangement of the droplets in this case is not particularly limited and can be determined as appropriate.

  In addition, when the drop volume of the imprint resin droplet is small and it is difficult to observe (measure) the diameter of the droplet, a plurality of droplets are dropped at one location to form a droplet that can be observed. Then, the droplets may be observed.

Then, the time-dependent change in the diameter of the imprint resin droplet is obtained as shown in the graph of FIG. 5, and the time T _{MAX at} which the droplet reaches the maximum diameter R _MAX is obtained.

Next, a change in the composition ratio due to volatilization of the imprint resin is measured. Examples of the method for determining the change in the composition ratio of the imprint resin include, for example, a method of actually measuring the composition ratio of the imprint resin dropped on the substrate to be transferred with the lapse of time, and dropping the imprint resin droplet before imprinting. Prepare multiple samples with different time to start the printing process (transfer timing) and measure the hardness, etching resistance, etc. of the imprinted resin film after imprinting in each sample. Examples thereof include a method for obtaining a change with time in the composition ratio of the print resin. And the limit time _TLMT which can maintain the composition ratio which can exhibit the function (characteristic) calculated _| required by the imprint resin is calculated _| required from the change of the composition ratio of the said imprint resin.

Then, from the graph shown in FIG. 5, the shorter one of the elapsed time from the time T _MAX when the droplet reaches the maximum diameter R _MAX and the limit time T _LMT (the limit time T in FIG. 5). _LMT ) and the droplet diameter at that time (diameter R _LMT in FIG. 5) are determined as the transfer timing for starting the imprint process (time T _INP and droplet diameter R _INP as an index for judging the transfer timing). be able to.

In this way, the transfer timing is determined, the droplet diameter R _INP (diameter R _LMT in FIG. 5) at the transfer timing, and the first region Pa1 and the second region Pa2 of the imprint mold 10 in contact with the droplet. Based on the surface shape of the liquid droplets, the wet and spread expected area of each droplet is calculated.

  After obtaining the transfer timing for starting the imprint process and the planned wet spreading area of the imprint resin droplets as described above, the number of the imprint resin droplets obtained in step S102 and the planned wet spreading area. Based on the above, the supply position of the imprint resin is determined (S104). The supply position of the imprint resin is determined so as not to cause a pattern defect (there is no unfilled portion of the imprint resin) based on the wetted and spread area of each droplet and the number of droplets of the imprint resin. Can be done.

  Subsequently, based on the imprint resin supply position, the imprint resin is supplied onto the transfer substrate (S105), and the droplets of the imprint resin are observed (S106). The state of the imprint resin droplet is preferably observed by obtaining an image of the droplet in plan view from the lower side of the transfer substrate. Then, it is confirmed that the imprint resin droplet state has reached the transfer timing for starting the imprint process determined as described above (S106), and the imprint process is started (S107).

Whether or not the state of the imprint resin droplet has reached the transfer timing for starting the imprint process is determined by the time T _INP (in FIG. 5) as an index for determining the transfer timing of the imprint resin droplet. Is observed until the limit time T _LMT ) elapses, and the diameter of the droplet is measured. The diameter of the droplet is a diameter R _INP (in FIG. 5, the diameter R _LMT ) as an index for judging the transfer timing described above. It can be determined by whether or not. When the imprint process is started after confirming that the diameter of the droplet has reached the diameter R _INP as an index for judging the transfer timing, each droplet wets and spreads in the planned area. It can be suppressed from occurring. In particular, since the diameter R _INP as an index for determining the transfer timing is set so that each droplet contacting the different surface shapes of the pattern area Pa of the imprint mold 10 spreads in an approximate shape, It is possible to effectively suppress the occurrence of a pattern defect in a portion where the droplets in different wetted regions contact each other (near the boundary between the first region Pa1 and the second region Pa2).

  The droplets of the imprint resin to be observed may be all the droplets existing on the transferred substrate, or may be a part of the droplets existing on the transferred substrate.

Even when the time T _INP (limit time T _LMT in FIG. 5) as an index for determining the transfer timing elapses, the diameter of the droplet R _INP (in FIG. 5 as an index for determining the transfer timing described above). Is not equal to the diameter R _LMT ), it is determined that there is a high possibility of pattern defects, and the imprint process is stopped. By stopping the imprint process in this manner, the occurrence of pattern defects can be suppressed, and the imprint resin can be prevented from being cured, so that the reuse of the transferred substrate can be facilitated.

  As described above, according to the imprint method according to the present embodiment, the area of the imprint mold in which the liquid droplets of the imprint resin are wet and spread is determined based on the surface shape of the imprint mold and the transfer timing. In addition to determining the dropping arrangement of the imprint resin droplets, the imprint process can be performed by checking the transfer timing. Therefore, according to the present embodiment, it is possible to prevent the occurrence of a pattern defect due to a difference in the wet spread of the imprint resin droplets during the imprint process.

[Imprint device]
Next, an embodiment of an imprint apparatus capable of performing the above-described imprint method will be described with reference to the drawings. FIG. 6 is a schematic configuration diagram illustrating the imprint apparatus according to the present embodiment.

  As shown in FIG. 6, the imprint apparatus 1 according to the present embodiment places an inkjet substrate (not shown) that drops the imprint resin droplets 20 on the transfer substrate 30 and the transfer substrate 30. The substrate stage 1A, the mold holder 1B that holds the imprint mold 10 so as to face the transfer substrate 30, and the imprint resin film formed on the transfer substrate 30 in contact with the imprint mold 10 are cured. Curing means (in the case where the imprint resin is an ultraviolet curable resin, a UV light source or the like, not shown), and a liquid of the imprint resin that is positioned below the substrate stage 1A and dropped onto the transfer substrate 30 The imaging unit 1C that can image the droplet 20 from the lower side of the transfer substrate 30 and the appropriate transfer timing are determined, and various operations of the imprint apparatus 1 are controlled. And a unit (not shown).

  As the imaging unit 1 </ b> C, an imaging device that can capture a moving image or a still image of the imprint resin droplet 20 dropped on the transfer substrate 30, for example, a visible light camera, an infrared camera, or the like can be used.

The control unit calculates the diameter of the imprint resin droplet 20 dropped on the transfer substrate 30 from the image data captured by the imaging unit 1C, calculates the imprint resin supply amount and the number of droplets, and transfers CPU for performing data processing such as calculation of timing (droplet diameter R _INP , elapsed time T _INP after dropping), determination of dropping arrangement of imprint resin, etc .; information on pattern area Pa of imprint mold 10 (pattern Information on the planar view area of the region Pa, the arrangement of the first region Pa1 and the second region Pa2, the structure of the fine unevenness patterns 12a and 12b formed in the regions Pa1 and Pa2, and the like. Set value of remaining film thickness of fine uneven pattern structure, calculated droplet diameter, imprint resin supply amount, number of droplets, transfer timing, imprint resin droplet A computer device or the like having a storage unit or the like for storing the lower arrangement or the like can be used.

In the imprint apparatus 1 having the above-described configuration, the control unit provides information on the pattern area Pa of the imprint mold 10 to be used (plan view area of the pattern area Pa, arrangement of the first area Pa1 and the second area Pa2). , Information on the structure and the like of the fine concavo-convex patterns 12a and 12b formed in the first and second regions Pa1 and Pa2, and the setting value of the remaining film thickness of the fine concavo-convex pattern structure formed on the transfer substrate 30. The imprint resin supply amount S, the number of imprint resin droplets, and the transfer timing (imprint resin droplet diameter R _INP and imprint processing start time T _INP ) are calculated. Determine the area where the droplets will spread out. Then, the controller determines the dropping arrangement of the imprint resin based on the supply amount S of the imprint resin, the number of droplets of the imprint resin, and the area where the imprint resin droplets are expected to spread.

  Next, based on the determined dropping arrangement of the imprint resin, the ink jet unit discretely drops the imprint resin onto the transfer substrate 30. Subsequently, the imaging unit 1 </ b> C acquires an image of the imprint resin droplet 20 from the lower side of the transfer substrate 30 and observes the state (diameter) of the droplet 20. When the control unit determines that the transfer timing is reached from the state (diameter) of the droplet and the elapsed time after the dropping, the control unit brings the imprint mold 10 and the imprint resin droplet 20 into contact with each other. An imprint resin is developed between the substrate to be transferred 30. Thereafter, the imprint resin is cured, the imprint mold 10 is peeled off, and a fine uneven pattern structure is formed.

  In the imprint apparatus 1 according to the present embodiment, the dropping arrangement of the imprint resin is determined on the basis of the surface shape of the pattern area Pa of the imprint mold 10 and the transfer timing, and on the transferred substrate 30 based on the dropping arrangement. The imprint process can be performed by observing the state (diameter) of the dropped imprint resin droplet 20 to determine the transfer timing. Therefore, according to the imprint apparatus 1 in the present embodiment, it is possible to prevent the occurrence of pattern defects due to the difference in the wet spread of the imprint resin droplets during the imprint process.

  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, the diameter R _INP of the droplets as an index for determining the transfer timing, the time T _MAX and limit time T _LMT droplets of imprintable resin becomes maximum diameter R _MAX whichever is shorter The maximum diameter R _MAX of the imprint resin droplets may be used as an index for determining the transfer timing as long as the volatilization of the imprint resin is negligible. In addition, as long as pattern defects do not occur, the substantial maximum diameter of the imprint resin droplets (for example, 90% or more with respect to the maximum diameter R _MAX ) may be used as an index for determining the transfer timing. Furthermore, as an index for determining the transfer timing, a plane view area of the droplet may be used instead of the diameter of the droplet of the imprint resin.

  In the above embodiment, the fine concavo-convex patterns 12a and 12b having different pattern structures are formed in each of the first region Pa1 and the second region Pa2 of the imprint mold 10, but the imprint that can be used in the present invention. The mold is not limited to such an embodiment, and at least two different shapes of the area in which the droplet spreads when contacting the droplet of the imprint resin in the pattern region Pa of the imprint mold 10 are different. It suffices if the area exists. As the imprint mold 10, for example, one type of fine concavo-convex pattern such as a line and space shape is formed in the pattern area Pa, and an area in which no pattern exists in the pattern area Pa (imprint resin in the area) In other words, a region having an area that can determine the shape of the region in which the droplet spreads out by the surface shape of the region may be used.

  In the above-described embodiment, the imaging unit 1C is located below the transfer substrate 30, and the image of the droplet of the imprint resin 20 is acquired from the lower side of the transfer substrate 30, but the imaging unit 1C is the mold holder. The image of the droplet of the imprint resin 20 may be acquired from the upper side of the imprint mold 10 located above 1B. In this case, the imprint mold 10 needs to be configured of a base material that can transmit imaging light.

  In the above embodiment, the imprint mold 10 has the convex structure portion 13 protruding from the main surface 11a side of the substrate 11, and the entire upper surface 13a of the convex structure portion 13 is the pattern region Pa, and the upper surface 13a (pattern region Pa) is formed with fine uneven patterns 12a and 12b, and a recess portion 14 is formed on the back surface 11b side facing the main surface 11a of the substrate 11, and the substrate to be transferred 30 is a flat plate. Although a certain example has been described as an example, it is not limited to such an embodiment. For example, the imprint mold is a flat plate, a part of the main surface forms a pattern region, and a fine uneven pattern is formed in the pattern region, and the transfer substrate is the main surface of the base material It has a convex structure part protruding from the side, a depression is formed on the back side facing the main surface of the substrate, and a transfer pattern is formed on the upper surface of the convex structure part by imprint processing Also good.

  The present invention is useful for manufacturing an imprint mold used in a nanoimprint process for forming a fine uneven pattern, manufacturing a semiconductor device using the imprint mold, and the like.

DESCRIPTION OF SYMBOLS 1 ... Imprint apparatus 10 ... Imprint mold 11 ... Base material 11a ... Main surface 12a, 12b ... Fine uneven | corrugated pattern 20, 20a, 20b, 20c ... Imprint resin 30 ... Transfer substrate Pa ... Pattern area | region Pa1 ... 1st area | region Pa2 ... 2nd area

Claims (8)

A fine uneven pattern is formed in the pattern area on the main surface side of the base material, and an imprint mold in which at least two types of areas having different surface shapes are included in the pattern area is discrete on the substrate to be transferred by an ink jet method. An imprint method for transferring the fine concavo-convex pattern to a supplied imprint resin,
Determining a supply amount of the imprint resin supplied on the transfer substrate;
Calculating the number of droplets of the imprint resin supplied on the transfer substrate based on the supply amount of the imprint resin;
A step of obtaining a region where the droplets are to spread on the transfer substrate when the pattern region of the imprint mold is brought into contact with the droplets of the imprint resin supplied on the transfer substrate. When,
Determining a supply position of the imprint resin on the transfer substrate based on the number of droplets of the imprint resin and a region where the droplets are scheduled to spread on the transfer substrate;
Supplying the imprint resin on the transfer substrate based on the supply position of the imprint resin;
The fine uneven pattern of the imprint mold is formed on the imprint resin droplets on the transfer substrate at a timing when the imprint resin droplets spread on the transfer target area on the transfer substrate. And an imprinting method comprising a step of contacting.   The area where the droplets are scheduled to spread on the transferred substrate is based on the planar view diameter of the droplets of the imprint resin supplied on the transferred substrate and the pattern structure of the fine uneven pattern. The imprint method according to claim 1, wherein the imprint method is obtained.   3. The imprint according to claim 2, wherein a diameter of the imprint resin droplet in plan view is a maximum diameter in plan view of the droplet of the imprint resin supplied onto the transfer substrate. Method.   Observing the state of droplets of the imprint resin supplied on the substrate to be transferred, and determining a timing at which the droplets of imprint resin wet and spread on the area to be spread on the substrate to be transferred. The imprint method according to claim 1, wherein:   The state of droplets of the imprint resin on the one surface of the transfer substrate is observed from the other surface side facing the one surface of the transfer substrate via the transfer substrate. 5. The imprint method according to 4.   The state of droplets of the imprint resin on one surface of the substrate to be transferred is observed through the imprint mold disposed to face one surface of the substrate to be transferred. 5. The imprint method according to 4.   The time for observing the state of the droplets of the imprint resin supplied on the substrate to be transferred is specified in advance, and the state of the droplets of the imprint resin is wetted in the region where the state of the droplets of the imprint resin is wet and spread within the observation time. 7. The fine uneven pattern of the imprint mold is brought into contact with a droplet of the imprint resin on the substrate to be transferred when a state where the imprint resin can spread is brought into contact. Imprint method. An imprint mold in which a fine concavo-convex pattern is formed in the pattern region on the main surface side of the substrate, and the pattern region includes at least two types of regions having different surface shapes, and the imprint supplied on the transfer substrate is used. An imprint apparatus for transferring the fine uneven pattern to a print resin,
A resin application part that discretely supplies the imprint resin onto the transfer substrate by an inkjet method;
When the pattern area of the imprint mold is brought into contact with droplets of the imprint resin supplied on the transfer substrate, the droplets spread to wet areas on the transfer substrate. A transfer timing determination unit for determining timing;
An imprint comprising: a transfer unit that contacts the droplets of the imprint resin on the transfer substrate with the fine uneven pattern of the imprint mold at a timing determined by the transfer timing determination unit. apparatus.

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