JP2009071229A - Imprint mold, manufacturing method for imprint mold and optical imprint method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imprint mold and a manufacturing method for imprint mold which do not lower detachability of the imprint mold and a resin pattern even when a repeated imprint method using the imprint mold is performed, and to provide an optical imprint method. <P>SOLUTION: In this imprint mold 100, a first mold pattern 40 and a second mold pattern 50 are formed on one surface of a substrate 11, and a first phase difference compensating pattern 45 and a second phase difference compensating pattern 55 are so formed on the other surface of the substrate as to face the first mold pattern 40 and the second mold pattern 50, respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imprint mold, a method for producing the imprint mold, and an optical imprint method using the imprint mold.

In recent years, it has been proposed to use an imprint method for forming a fine pattern in a manufacturing process of a semiconductor device, a display, a recording medium, a biochip, an optical device, or the like (for example, Non-Patent Document 1 and Non-Patent Document 2). reference).
In the imprint method, a nanometer-level method is particularly referred to as a nanoimprint method. Hereinafter, the imprint method is also simply referred to as a nanoimprint method.

  In the imprint method, a mold called an imprint mold (sometimes called a template) in which a pattern corresponding to a negative and positive reversal image of a pattern to be finally transferred is formed is impressed on a resin, and the state The pattern is transferred by curing the resin. At this time, a photoimprint method is known in which a photocurable resin is cured by irradiating exposure light (see, for example, Patent Document 1).

In the imprint method, the peelability between the imprint mold and the resin pattern generated on the substrate is extremely important. This will be described with reference to FIGS. In general, the curing of the resin causes resin shrinkage, and stress is generated between the imprint mold and the resin pattern, and various pattern peeling phenomena occur.
First, the imprint mold 201 is embossed on a resin film made of a photoresist or the like formed on the transfer substrate 211, and UV irradiation or the like is performed to cure the resin, thereby forming a resin pattern 221 (FIG. 11A). reference).
Next, in the step of separating the imprint mold 201 and the resin pattern 221, a phenomenon in which the resin pattern part 221a moves to the imprint mold 201 side (see FIG. 11B) or the resin pattern part 221a is imprinted. It is known that a phenomenon (see FIG. 11C) that remains on the print mold 201 side occurs and a defect occurs in the resin pattern 221 on the transfer substrate 211.

  Further, in the process of separating the imprint mold 201 and the resin pattern 221, defects such as the resin pattern 221b and the resin pattern 221c shown in FIG. It has been reported that it frequently occurs at the corner portion that is the boundary of the concave pattern portion (see, for example, Non-Patent Document 3).

  Further, as a method for improving the peelability of the imprint mold 201 with respect to the resin pattern 211, a method of applying a fluoropolymer having a small surface energy to the surface of the imprint mold 201 as a release agent has been proposed (see, for example, Patent Document 2). ).

On the other hand, in the field of photolithography, an exposure method has been proposed in which exposure intensity is controlled by using coherent exposure light and a photomask whose optical path difference is controlled (see, for example, Patent Document 3).
JP 2000-194142 A JP 2002-283354 A JP-A-4-359254 Appl. phys. Lett. , Vol. 67, p3314 (1995) Nanoimprint Technology Thorough Diffraction Electric Journal Published November 22, 2004, p20-38 Y. Hirai, et al. J. et al. Vac. Sci. Technol. B21 (6), 2003

  However, even if the release agent is applied to the surface of the imprint mold, if the imprint method is repeatedly performed, the release agent is gradually peeled off from the surface of the imprint mold, and the peelability between the imprint mold and the resin pattern is lowered. Has the problem.

  The present invention has been made in order to solve the above-described problem, and an imprint mold and an imprint in which the releasability between the imprint mold and the resin pattern does not deteriorate even when the imprint mold is repeatedly performed. An object of the present invention is to provide a method for producing a print mold and an optical imprint method. In particular, an object of the present invention is to provide an imprint mold that forms a pattern having two or more mold patterns, for example, a pattern similar to a damascene structure that is a kind of wiring structure in a semiconductor device.

In order to achieve the above object in the present invention, first, in claim 1, in an imprint mold used in an optical imprint method for transferring a fine uneven pattern,
The uneven pattern is formed on the substrate so that the difference between the cross-sectional dimension of the convex pattern part and the cross-sectional dimension of the concave pattern part is equal to the optical path length corresponding to the half wavelength of the coherent exposure light used in the optical imprint method or an odd multiple of the half wavelength. The first mold pattern 40 and the second mold pattern 50 are formed on one surface of the substrate 11, and the first phase difference correction is performed so as to face the first mold pattern 40 on the other surface of the substrate 11. The imprint mold is characterized in that a second phase difference correction pattern 55 is formed so that the pattern 45 faces the second mold pattern 50.

  Further, in claim 2, the optical path length between the first mold pattern 40 and the first phase difference correction pattern 45 and the optical path between the second mold pattern 50 and the second phase difference correction pattern 55. 2. The imprint mold according to claim 1, wherein the length is equal to an optical path length corresponding to a half wavelength of the exposure light or an odd multiple of the half wavelength.

Moreover, in Claim 3, in the manufacturing method of an imprint mold,
A step of forming the sacrificial film 21 on both surfaces of the substrate 11, a step of forming the first mold pattern 40 and the second mold pattern 50 on one surface of the substrate 11,
Filling the first mold pattern 40 and the second mold pattern 50 with a protective layer;
Forming a first phase difference correction pattern 45 and a second phase difference correction pattern 55 on the other surface of the substrate 11;
And a step of peeling off the protective layer 35. The imprint mold manufacturing method is characterized by comprising:

Furthermore, in claim 4, in the optical imprint method of curing a resin through an imprint mold by exposure light to form a transfer pattern,
Applying a photocurable resin to the transfer substrate 111 to form a photocurable resin film 12);
The imprint mold 100 according to claim 1 or 2 is bonded to the transfer substrate 111 on which the photocurable resin film 121 is formed, and exposure light is irradiated to the photocurable resin film 121 from the imprint mold 100 side. Process,
Peeling the imprint mold 100 from the transfer substrate 111;
Performing light irradiation for curing on the photocurable resin film 121 irradiated with exposure light;
And a step of removing the remaining film portion 141. The optical imprint method is characterized by comprising:

  By optical imprinting using the imprint mold of the present invention, the phase of the exposure light is reversed by 180 ° at the boundary between the convex mold pattern portion and the concave mold pattern portion, and the boundary between the convex mold pattern portion and the concave mold pattern portion. The intensity of exposure light can be reduced at the corner portion. As a result, the degree of curing of the photocurable resin at the pattern corner portion can be lowered, and the generation of stress due to resin shrinkage can be reduced. Therefore, it is possible to suppress the occurrence of defects in the resin pattern in the step of peeling the imprint mold from the resin pattern.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a schematic sectional view showing an embodiment of the imprint mold of the present invention.
In the imprint mold 100 of the present invention, the first mold pattern 40 and the second mold pattern 50 are formed on one surface of the substrate 11, and the first mold pattern 40 is opposed to the first mold pattern 40 on the other surface of the substrate 11. The second phase difference correction pattern 55 is formed so that the one phase difference correction pattern 45 faces the second mold pattern 50. Further, the first mold pattern 40, the first phase difference correction pattern 45, the second mold pattern 50, and the second phase difference correction pattern 55 have an optical path length corresponding to a half wavelength of the exposure light or an odd multiple of the half wavelength. It is characterized by being equal to.

FIG. 2 explains the principle of optical imprinting using the imprint mold of the present invention, and is an explanatory view in which coherent exposure light is irradiated to the imprint mold.
The wavefront A of the coherent light 200 incident on the imprint mold in FIG. 2A passes through the distance A and the distance B between the uneven portions of the imprint mold indicated by 410 and 420 parts, respectively. If the difference distance C between the cross-sectional dimension (distance A) of the convex pattern part and the cross-sectional dimension (distance B) of the concave pattern part is set to an optical path length corresponding to a half wavelength of the coherent exposure light or an odd multiple of the half wavelength, the wavefront B is emitted as light that is phase-inverted relative to each other at adjacent 410 and 420.

The light intensity will be described with reference to FIGS. In the light transmitted through 410 and 420, the light intensity is the same (here, for convenience of explanation, the transmittance attenuation of the mold 100 itself is ignored). Since the phase is inverted, the light amplitudes (intensities) of 410 and 420 on the wavefront B are separated for convenience, and the vertical axis is relatively opposed to the top and bottom of the drawing. At this time, due to the diffraction effect by the corners C and D, a tail-like diffracted light 430 is generated. In the diffracted light 430, the light intensity is the same, and in the combined light intensity 440 shown in FIG. 2C, the light energy intensity at the corner C is close to zero because they are canceled by the inverted phase. This zero light energy portion occurs selectively at the wavefront B position where phase inversion occurs. For this reason, only the corner portion (corner portion C) which is the boundary between the convex pattern portion and the concave pattern portion of the resin pattern where stress is concentrated at the time of peeling occurs selectively, and a portion where the photocurable resin 120 is not cured is generated. Adhesive force or frictional force due to shrinkage or expansion of the photocured resin in the mold does not act.

The distance C necessary for the phase inversion shown in FIG. 2 will be described. As described above, the phase inversion mechanism may be an odd multiple of one half of the wavelength (λ) or one half of the wavelength (λ) in the optical path length. When the light source wavelength is λ (nm), the refractive index of the imprint mold material is n _q , the difference between the cross-sectional dimension of the convex pattern part and the cross-sectional dimension of the concave pattern part is T, and the refractive index of the atmosphere is n _air Is represented by Equation 1 below.

具体例として、例えば、下記の条件の場合、位相反転に必要なＴは、式１より、１９３ｎｍとなる。
λ：１９３ｎｍ（ＡｒＦエキシマレーザーの波長）
ｎ_q：１．５（石英ガラス基板の屈折率）
ｎ_air：１（大気の屈折率）
ｎ：１（整数）
また、本発明のインプリントモールドは基板の一方の面に第一モールドパターンと第二モールドパターンが形成され、基板の他方の面に前記第一モールドパターンと相対するように第一位相差補正用パターンが、前記第二モールドパターンと相対するように第二位相差補正用パターンがそれぞれ形成されている。
第一モールドパターンと相対するように形成することにより、第一位相差補正用パターンの凹部の深さを制御することで、凹パターン部の断面寸法を制御することが出来る。このため、第一モールドパターンの寸法によらず、凸パターン部の断面寸法と凹パターン部の断面寸法の差分が、コヒーレントな露光光の半波長または半波長の奇数倍に相当する光路長と等しくすることが出来る。このため、任意寸法の第一モールドパターンを形成する場合であっても、第一位相差補正用パターンの凹部の深度を制御することで、光路差を制御することが出来る。

As a specific example, for example, under the following conditions, T required for phase inversion is 193 nm from Equation 1.
λ: 193 nm (wavelength of ArF excimer laser)
n _q : 1.5 (refractive index of quartz glass substrate)
n _air : 1 (atmospheric refractive index)
n: 1 (integer)
In the imprint mold of the present invention, the first mold pattern and the second mold pattern are formed on one surface of the substrate, and the first phase difference correction is performed so as to face the first mold pattern on the other surface of the substrate. Second phase difference correction patterns are respectively formed so that the pattern faces the second mold pattern.
By forming the first mold pattern so as to face the first mold pattern, the cross-sectional dimension of the concave pattern portion can be controlled by controlling the depth of the concave portion of the first phase difference correction pattern. Therefore, regardless of the dimensions of the first mold pattern, the difference between the cross-sectional dimension of the convex pattern part and the cross-sectional dimension of the concave pattern part is equal to the optical path length corresponding to the half wavelength of the coherent exposure light or an odd multiple of the half wavelength. I can do it. For this reason, even when the first mold pattern having an arbitrary dimension is formed, the optical path difference can be controlled by controlling the depth of the concave portion of the first phase difference correction pattern.

FIG. 3 shows an example of an imprint mold when the first phase difference correction pattern is formed. 3, the dimensions of the first mold pattern t _1, the dimensions of the first phase difference correction pattern and t _2.
In this case, in Equation 1, T corresponding to the difference between the cross-sectional dimension of the convex pattern portion and the cross-sectional dimension of the concave pattern portion is divided into two layers, so that T and n are different t ₁ , t ₂ , n _r. , N _q . Further, in the case of an imprint mold, the refractive index of the light propagation medium that causes phase inversion is generally in the atmosphere (refractive index n _air = 1) at the stage of the wavefront A, and in the photocurable resin at the wavefront B (refractive index). n _r ).

  Equation 1 is transformed into Equation 2.

図３に示す場合、屈折率ｎと、凸パターン部の断面寸法と凹パターン部の断面寸法の差分に相当するＴが２分されるので、ｔ₁、ｔ₂、ｎ_r、ｎ_qについて下記に示す式３の関係式を満たせば良い。

In the case shown in FIG. 3, since the refractive index n and T corresponding to the difference between the cross-sectional dimensions of the convex pattern portion and the concave pattern portion are divided into two, t ₁ , t ₂ , n _r , and n _q are described below. It is sufficient to satisfy the relational expression of Expression 3 shown below.

具体例として、例えば、石英ガラス基板に１００ｎｍの凹凸パターンを形成したインプリントモールド１００（ｔ₁、ｎ_q）の場合、必要な位相反転に必要な第一位相差補正用パターンの寸法ｔ₂は、式３より、２３３ｎｍとなる。
λ：１９３ｎｍ（ＡｒＦエキシマレーザーの波長）
ｔ₁：１００ｎｍ（第一モールドターンの寸法）
ｎ_q：１．５（石英ガラス基板の屈折率）
ｎ_r：１．７（光硬化樹脂の屈折率）
ｎ_air：１（大気の屈折率）
ｎ：１（整数）
図４に、図３に示す場合における、光強度の分布を示す。インプリントモールドを透過した合成光強度は波面Ｂ位置で図４（ｂ）に示す分布となり、剥離時に応力が集中する樹脂パターンの凸パターン部と凹パターン部の境界であるコーナー部が、光エネルギーゼロ部に対応する部に対応する。このため、露光の工程において、剥離時に応力が集中する樹脂パターンの凸パターン部と凹パターン部の境界であるコーナー部が、未硬化の部位となり、樹脂収縮による応力の発生を低下させることが出来る。
以上で本発明の原理を説明した。

As a specific example, for example, in the case of the imprint mold 100 (t ₁ , n _q ) in which a concavo-convex pattern of 100 nm is formed on a quartz glass substrate, the dimension t ₂ of the first phase difference correction pattern necessary for necessary phase inversion is From Equation 3, 233 nm is obtained.
λ: 193 nm (wavelength of ArF excimer laser)
t ₁ : 100 nm (dimension of the first mold turn)
n _q : 1.5 (refractive index of quartz glass substrate)
n _r : 1.7 (refractive index of photo-curing resin)
n _air : 1 (atmospheric refractive index)
n: 1 (integer)
FIG. 4 shows the light intensity distribution in the case shown in FIG. The composite light intensity transmitted through the imprint mold has the distribution shown in FIG. 4B at the wavefront B position, and the corner portion which is the boundary between the convex pattern portion and the concave pattern portion of the resin pattern where stress is concentrated at the time of peeling is light energy. Corresponds to the part corresponding to the zero part. For this reason, in the exposure process, the corner portion which is the boundary between the convex pattern portion and the concave pattern portion of the resin pattern where stress is concentrated at the time of peeling becomes an uncured portion, and the generation of stress due to resin shrinkage can be reduced. .
The principle of the present invention has been described above.

  FIG. 5 illustrates an example of a mold pattern having a two-stage configuration that further causes phase inversion twice. For convenience, reference will be made to FIG. 2 described above and the description thereof, and description will be made using the same symbols. In FIG. 5, the left half surface (wave fronts A to B) is an imprint mold 300, which is the same as FIG. Therefore, the principle of phase inversion is also as described above. Further, the right half surface (wavefronts B to C) of the second-stage mold pattern was used as an additional recording mode as the imprint mold 400.

Similar to 410 and 420 parts in the imprint mold 300, the phase inversion at 420 and 415 parts of the imprint mold 400 may be expressed at the wavefront C, and it may be considered that coherent light is incident on the wavefront B position. It is obvious that the optical path length should satisfy A ′, B ′, and C ′ that have the same relationship as the distances A, B, and C in the imprint mold 300. It may require even likewise secured as the phase difference correction pattern optical path length required for phase inversion and t ₂ in FIG. 2 in the imprint mold 400. In this case, since phase inversion has already been established at 410 and 420 parts on the imprint mold 300 side, it may be formed at 415 parts.

Hereinafter, the imprint mold manufacturing method of the present invention will be described.
FIGS. 6A to 6D, FIGS. 7E to 7H, and FIGS. 8I to 8K are schematic cross-sectional views illustrating an example of the imprint mold manufacturing method of the present invention in the order of steps. is there.
First, the sacrificial film 21 is formed on both surfaces of the substrate 11 (see FIG. 6A).
The substrate 11 is required to be a material that transmits exposure light used in the optical imprint method. Examples of a material that transmits general exposure light include quartz glass.

  Next, a photoresist is applied to one surface of the substrate 11, and patterning processing such as pattern exposure and development is performed to form a resist pattern 31 (see FIG. 6B).

Next, the sacrificial film 21 is etched by using the resist pattern 31 as a mask to form a sacrificial film pattern 21a (see FIG. 6C), and the substrate 11 is further subjected to a known fine processing technique such as dry etching. Etching is performed to a predetermined depth, and the resist pattern 31 is stripped to form the first mold pattern 40 (see FIG. 6D).
As a method for forming the first mold pattern 40, a well-known fine processing technique may be used as appropriate according to the desired dimension and shape of the mold pattern. For example, it can be formed by appropriately combining a photolithography method, a dry etching method, a wet etching method, a laser processing method, a micromachining method, and the like.

Next, the first mold pattern 40 is filled with a protective material to form a protective layer 32 (see FIG. 7E). By filling the first mold pattern 40 with a protective material, there is an advantage that the mechanical strength of the already formed mold pattern portion is reinforced. For this reason, the damage by the process of the 2nd mold pattern mentioned later can be prevented.
The protective material is not particularly limited as long as it is a material that can be filled to the first mold pattern 40 with a sufficient degree.

  Next, a photoresist is applied on the protective layer 32 and the sacrificial film 21a, and a patterning process such as pattern exposure and development is performed to form a resist pattern 33 (see FIG. 7F).

Next, the sacrificial film 21 is etched using the resist pattern 33 as a mask to form a sacrificial film pattern 21b (see FIG. 7G), and the substrate 11 is dried using the resist pattern 33 and the sacrificial film pattern 21b as a mask. A second mold pattern 50 is formed by etching at a predetermined depth using a known fine processing technique such as etching (see FIG. 7H).
As a method of forming the second mold pattern 50, a well-known fine processing technique may be used as appropriate according to the desired size and shape of the mold pattern. For example, it can be formed by appropriately combining a photolithography method, a dry etching method, a wet etching method, a laser processing method, a micromachining method, and the like.

  Next, the sacrificial film pattern 21b, the resist pattern 33, and the protective layer 32 are stripped to form the first mold pattern 40 and the second mold pattern 50 on one surface of the substrate 11 (see FIG. 8 (i)). .

Next, the first mold pattern 40 and the second mold pattern 50 are filled with a protective material to form a protective layer 35 (see FIG. 8J). By filling the first mold pattern 40 and the second mold pattern 50 with a protective material, there is also an advantage that the mechanical strength of the already formed mold pattern portion is reinforced.
The protective material may be any material that fills the first mold pattern 40 and the second mold pattern 50 with a good degree, and is not particularly limited.

Next, the first phase difference correction pattern 45 is placed on the other surface of the substrate 11 on which the first mold pattern 40 and the second mold pattern 50 are formed, at a position facing the first mold pattern 40. The second phase difference correction pattern 55 is formed at a position opposite to the first mold pattern 40 by the same process as the first mold pattern 40 and the second mold pattern 50, and the first mold pattern 40 and the second mold pattern 40 are formed on one surface of the substrate 11. As a result of the two mold patterns 50, the imprint mold 100 of the present invention in which the first phase difference correction pattern 45 and the second phase difference correction pattern 55 are formed on the other surface can be obtained (see FIG. 8 (k)). ).
Here, by controlling the depth of the concave portions of the first phase difference correction pattern 45 and the second phase difference correction pattern 55, the cross-sectional dimension of the concave pattern portion can be controlled. Therefore, regardless of the dimensions of the first mold pattern 40 and the second mold pattern 50, the difference between the cross-sectional dimension of the convex pattern part and the cross-sectional dimension of the concave pattern part is half the wavelength of the coherent exposure light or an odd multiple of the half wavelength. Can be made equal to the optical path length corresponding to.

As a method of forming the first phase difference correction pattern 45 and the second phase difference correction pattern 55, the same process as that of the first mold pattern 40 and the second mold pattern 50 can be applied. .
At this time, the first phase difference correction pattern 45 at a position facing the first mold pattern 40 and the second phase difference correction pattern 55 at a position facing the second mold pattern 50 are accurately aligned. is required.

Hereinafter, an optical imprint method for forming a transfer pattern on a transfer substrate on which a photosensitive resin film is formed using the imprint mold 100 of the present invention will be described.
FIGS. 9A to 9B and FIGS. 10C to 10E are schematic configuration sectional views showing an example of optical imprinting using the imprint mold 100 of the present invention in the order of steps.
First, the imprint mold 100 of the present invention is prepared, and a photocurable resin is applied to the transfer substrate 111 to form a photocurable resin film 121 (see FIG. 9A).

Next, the imprint mold 100 and the transfer substrate 111 on which the photo-curable resin film 121 is formed are bonded in the atmosphere, and irradiation with coherent exposure light for resin curing is performed. The photo-curable resin film 121 between them is cured (see FIG. 9B).
The imprint mold 100 and the transfer substrate 111 may be joined in a vacuum in order to prevent air in the first mold pattern 40 and the second mold pattern 50 from staying as bubbles.

  Next, the imprint mold 100 is pulled back in the direction opposite to the bonding direction of the transfer substrate 111, the imprint mold 100 is peeled from the transfer substrate 111, and the corner C of the photocurable resin pattern 131 is formed on the transfer substrate 111. The photocurable resin pattern 131 and the remaining film part 141 in which an uncured part exists are formed. (See FIG. 10 (c)).

  Next, light irradiation is performed to cure the photocurable resin pattern 131 and the uncured portion of the corner portion C of the photocurable resin pattern 131 (see FIG. 10D). This curing does not necessarily require coherent exposure light, and a light source having another wavelength may be used as long as the photocurable resin pattern 131 can be cured.

  Finally, the remaining film portion 141 is incinerated with oxygen plasma or the like, and a transfer pattern 132 is formed on the transfer substrate 111 by the optical imprint method of the present invention (see FIG. 10E).

In the optical imprint method of the present invention, the difference between the cross-sectional dimension of the convex pattern part and the cross-sectional dimension of the concave pattern part is equal to the optical path length corresponding to the half wavelength of the coherent exposure light or an odd multiple of the half wavelength. , The phase of the exposure light is inverted by 180 ° at the boundary between the convex pattern portion and the concave pattern portion, and the intensity of the exposure light can be reduced at the corner portion that is the boundary between the convex pattern portion and the concave pattern portion. .
For this reason, the degree of curing of the photo-curing resin at the pattern corner portion can be lowered, and the generation of stress due to resin shrinkage can be reduced. Therefore, it becomes possible to suppress the occurrence of defects in the resin pattern in the step of peeling the imprint mold from the resin pattern.

  The imprint mold of the present invention is expected to be used in a wide range of fields where fine pattern formation is desired. For example, semiconductor devices, optical components such as optical waveguides and diffraction gratings, recording devices such as hard disks and DVDs, life It is expected to be used in the manufacturing process of products such as biochips used for DNA analysis and the like in the science field, diffusion plates and light guide plates used for image / video displays in the display field and the like.

  Hereinafter, the present invention will be described in detail by way of examples.

  First, a sacrificial film 21 made of chromium (Cr), which is a conductive metal, was formed on both surfaces of a substrate 11 made of a quartz glass substrate (FIG. 6A).

  Next, a photoresist was applied to one surface of the substrate 11, and patterning processing such as pattern exposure and development was performed to form a resist pattern 31 (see FIG. 6B).

Next, the sacrificial film 21 is etched using the resist pattern 31 as a mask (see FIG. 6C), and further, a dry etching method using a reactive etching (RIE) method using a mixed gas of chlorine and oxygen is used. The resist pattern 31 is etched to a predetermined depth.
Was peeled to form a first mold pattern 40 (see FIG. 6D).

  Next, the first mold pattern 40 was filled with a protective material to form a protective layer 32 (see FIG. 7E).

  Next, a photoresist was applied on the protective layer 32 and the sacrificial film 21a, and a patterning process such as pattern exposure and development was performed to form a resist pattern 33 (see FIG. 7F).

Next, the sacrificial film 21 is etched using the resist pattern 33 as a mask (see FIG. 7G), and reactive etching with a mixed gas of C ₂ F ₆ and oxygen is performed using the resist pattern 33 and the sacrificial film pattern 21b as a mask (see FIG. 7G). The substrate 11 was etched to a predetermined depth using a dry etching method based on the RIE method to form a second mold pattern 50 (see FIG. 7H).

  Next, the sacrificial film pattern 21b, the resist pattern 33, and the protective layer 32 were peeled off to form the first mold pattern 40 and the second mold pattern 50 on one surface of the substrate 11 (see FIG. 8 (i)). .

  Next, the first mold pattern 40 and the second mold pattern 50 were filled with a protective material to form a protective layer 35 (see FIG. 8 (j)).

  Next, in the same manufacturing process as the first mold pattern 40 and the second mold pattern 50, the first mold pattern 40 and the second mold pattern 50 are formed on the other surface of the substrate 11 on which the first mold pattern 40 and the second mold pattern 50 are formed. A first phase difference correction pattern 45 and a second phase difference correction pattern 55 are formed at positions opposite to each other and a position opposite to the second mold pattern 50, respectively, and the first mold pattern 40 is formed on one surface of the substrate 11. And the 2nd mold pattern 50 was able to obtain the imprint mold 100 of this invention in which the 1st phase difference correction pattern 45 and the 2nd phase difference correction pattern 55 were formed in the other surface (FIG. 8 ( k)).

  First, the imprint mold 100 of the present invention prepared in Example 1 was prepared, and a photocurable resin was applied to the transfer substrate 111 to form a photocurable resin film 121 (see FIG. 9A). ).

  Next, the imprint mold 100 and the transfer substrate 111 on which the photo-curable resin film 121 is formed are bonded in the atmosphere, and irradiation with coherent exposure light for resin curing is performed. The photo-curable resin film 121 between them was cured (see FIG. 9B).

  Next, the imprint mold 100 is pulled back in the direction opposite to the bonding direction of the transfer substrate 111, the imprint mold 100 is peeled from the transfer substrate 111, and the corner C of the photocurable resin pattern 131 is formed on the transfer substrate 111. The photocurable resin pattern 131 and the remaining film part 141 in which an uncured part exists were formed. (See FIG. 10 (c)).

  Next, light irradiation was performed to cure the photocurable resin pattern 131 and the uncured portion of the corner C of the photocurable resin pattern 131 (see FIG. 10D).

  Finally, the remaining film portion 141 was incinerated with oxygen plasma or the like, and a transfer pattern 132 was formed on the transfer substrate 111 by the optical imprint method of the present invention (see FIG. 10E).

It is a typical composition sectional view showing one example of an imprint mold of the present invention. It is explanatory drawing explaining the principle of the imprint mold of this invention. It is explanatory drawing explaining the principle of the imprint mold of this invention. It is explanatory drawing which shows the light intensity at the time of irradiating coherent exposure light to the imprint mold of this invention. It is explanatory drawing which shows the light intensity at the time of irradiating coherent exposure light to the imprint mold of this invention. (A)-(d) is a partial schematic structure sectional drawing which shows a part of process of the manufacturing method of the imprint mold of this invention. (E)-(h) is a partial schematic structure sectional drawing which shows a part of process of the manufacturing method of the imprint mold of this invention. (I)-(k) is a partial schematic structure sectional drawing which shows a part of process of the manufacturing method of the imprint mold of this invention. (A)-(b) is a partial schematic structure sectional drawing which shows a part of process of one Example of the optical imprint method using the imprint mold 100 of this invention. (C)-(e) is a partial schematic structure sectional drawing which shows a part of process of one Example of the optical imprint method using the imprint mold 100 of this invention. (A)-(d) is a partial schematic structure sectional drawing which shows an example of the imprint method using the conventional imprint mold.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Substrate 21 ... Sacrificial film 21a, 21b ... Sacrificial film pattern 31, 33 ... Resist pattern 32, 35 ... Protective layer 40 ... First mold pattern 45 ... First phase difference correction pattern 50 ... ... second mold pattern 55 ... second phase difference correction pattern 100, 201 ... imprint mold 111 ... transfer base 121 ... photo-curable resin film 131 ... photo-curable resin pattern 132 ... transfer pattern 141 …… Remaining film portion 211 …… Transfer substrate 221 …… Resin pattern 221a …… Part of resin pattern 221b, 221c …… Resin pattern

Claims (4)

In the imprint mold used in the optical imprint method for transferring a fine uneven pattern,
The uneven pattern is formed on the substrate so that the difference between the cross-sectional dimension of the convex pattern part and the cross-sectional dimension of the concave pattern part is equal to the optical path length corresponding to the half wavelength of the coherent exposure light used in the optical imprint method or an odd multiple of the half wavelength. The first mold pattern (40) and the second mold pattern (50) are formed on one surface of the substrate (11), and the first mold pattern (40) is formed on the other surface of the substrate (11). The first phase difference correction pattern (45) is formed so as to face the second mold pattern (50), and the second phase difference correction pattern (55) is formed so as to face the second mold pattern (50). Imprint mold.   The optical path length between the first mold pattern (40) and the first phase difference correction pattern (45) and the optical path between the second mold pattern (50) and the second phase difference compensation pattern (55). 2. The imprint mold according to claim 1, wherein the length is equal to an optical path length corresponding to a half wavelength of the exposure light or an odd multiple of the half wavelength. In the imprint mold manufacturing method,
Forming a sacrificial film (21) on both surfaces of the substrate (11), forming a first mold pattern (40) and a second mold pattern (50) on one surface of the substrate (11);
Filling the first mold pattern (40) and the second mold pattern (50) with a protective material to form a protective layer (35);
Forming a first phase difference correction pattern (45) and a second phase difference correction pattern (55) on the other surface of the substrate (11);
And a step of peeling off the protective layer (35). In the light imprint method of curing a resin through an imprint mold by exposure light and forming a transfer pattern,
Applying a photocurable resin to the transfer substrate (111) to form a photocurable resin film (121);
The imprint mold (100) according to claim 1 or 2 is joined to a transfer substrate (111) on which a photocurable resin film (121) is formed, and the photocurable resin is bonded from the imprint mold (100) side. Irradiating the film (121) with exposure light;
Peeling the imprint mold (100) from the transfer substrate (111);
Irradiating the photocurable resin film (121) irradiated with exposure light with light for curing;
And a step of removing the remaining film portion (141).

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