JP2015112865A - Imprint mold, method for manufacturing imprint mold, and method for forming pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imprint mold capable of preventing transfer failure to a transfer material caused by the difference in densities of uneven patterns in uneven pattern area from occurring, in an imprint method, to provide a method for manufacturing the same, and to provide a pattern molding.SOLUTION: In an imprint mold 130 for forming uneven patterns to a transfer material 132, an uneven pattern area having a dense area of uneven patterns 133 and a sparse area of uneven patterns 134 is provided on a basal plate, and auxiliary patterns 135 for uniformizing a distribution between the uneven patterns 134 of the sparse area and the uneven patterns 133 of the dense area are provided in the uneven pattern area.

Description

  The present invention relates to an imprint mold having a concavo-convex pattern, a method for producing the imprint mold, and a method for forming a pattern on a transfer material by transferring the concavo-convex pattern of the imprint mold.

In recent years, there is a demand for a method for forming a specific fine uneven pattern (three-dimensional structure pattern) according to various applications.
For example, semiconductor devices, optical elements, wiring circuits, data storage media (hard disks, optical media, etc.), medical materials (analysis test chips, microneedles, etc.), bio devices (biosensors, cell culture substrates, etc.), precision testing Applications such as equipment members (inspection probes, sample holding members, etc.), display panels, panel members, energy devices (solar cells, fuel cells, etc.), microchannels, microreactors, MEMS devices, imprint molds, photomasks, etc. It is done.

As a method for forming such a fine concavo-convex pattern, a pattern transfer technique called an imprint method has been proposed (see, for example, Non-Patent Document 1).
In the imprint method, an original plate called an imprint mold on which a concavo-convex pattern corresponding to a negative-positive reversal image of the concavo-convex pattern to be finally transferred is impressed on a transfer material, and the transfer material is cured in that state. Thus, the concavo-convex pattern is transferred. By repeatedly transferring, a fine pattern can be easily formed.

For example, Patent Document 1 proposes a thermal imprint method in which a transfer material is cured by heat.
For example, Patent Document 2 proposes an optical imprint method in which a transfer material is cured by exposure.

As an example, pattern formation by a conventional general optical imprint method will be described with reference to FIG.
First, as shown in FIG. 1A, a transfer material 112 is laminated on a transfer substrate 111, and an imprint mold 110 on which a concavo-convex pattern is formed is disposed so as to face the transfer substrate.
Next, as shown in FIG. 1B, the transfer material 112 and the imprint mold 110 are brought into contact with each other, and in this state, the UV light 113 is irradiated to cure the transfer material 112.
Next, as shown in FIG. 1C, the imprint mold 110 is peeled away from the transfer substrate 111, thereby obtaining a pattern forming body having the transfer pattern 114.
Further, as shown in FIG. 1D, since the portion pressed by the convex portion of the imprint mold 110 remains as a thin resin film on the transfer substrate 111, the remaining film is removed by O ₂ RIE method or the like. You may do it.

JP 2004-335012 A JP 2000-194142 A

Applied Physics Letters, vol. 67, p. 3314, 1995

In the concavo-convex pattern formed on the imprint mold, when the pattern portion in the same substrate has a sparse / dense bias (FIG. 2A), the amount of transfer material filled in the dense region 123 and the sparse region 124 is different. Therefore, the distribution of the remaining film generated in the formed transfer pattern 125 is biased (FIG. 2B). This biased residual film distribution leads to a deviation between the height of the transfer pattern 125 in the dense region 123 and the height of the transfer pattern 125 in the sparse region 124.
Further, in the step of removing the remaining film by the O ₂ RIE method, the transfer pattern 125 is etched together with the remaining film layer, and therefore, the height of the transfer pattern 125 in the dense region 123 and the height of the transfer pattern 125 in the sparse region 124. When the deviation occurs, there arises a problem that the height of the transfer pattern 126 is uneven even after the residual film is removed (FIG. 2C).

  The present invention has been made to solve the above-described problems. When an uneven pattern having a sparse / dense bias is transferred using an imprint method, a uniform residual film height and a residual film after removal are removed. It is an object of the present invention to provide an imprint mold capable of forming a uniform transfer pattern height, a manufacturing method thereof, and a method of forming a pattern on a transfer material by transferring an uneven pattern of the imprint mold.

  The invention according to claim 1 includes a concavo-convex pattern region having a concavo-convex pattern formed by a combination of a concave portion and a convex portion formed on one surface of a substrate, and embossing the concavo-convex pattern region onto a transfer material on a transfer substrate. In the imprint mold for forming a transfer pattern corresponding to the concavo-convex pattern on the transfer material in the concavo-convex pattern region so that the remaining film layer formed when the concavo-convex pattern region is embossed on the transfer material is uniform. Are provided with an auxiliary pattern.

  The invention according to claim 2 is characterized in that the auxiliary pattern includes a concave portion that accommodates a part of the transfer material in the uneven pattern region.

  The invention according to claim 3 is characterized in that the concave portion of the auxiliary pattern is formed with a width and a depth for controlling a flow amount of the transfer material in the uneven pattern region.

  The invention according to claim 4 is characterized in that the width and depth of the concave portion of the auxiliary pattern are determined based on the volume of the transfer material accommodated in the concave / convex pattern or the area of the concave / convex pattern.

  The invention according to claim 5 is a method for producing an imprint mold according to any one of claims 1 to 4, wherein a first hard mask layer and a first resist material are sequentially coated on an upper surface of a substrate. A step of patterning the first resist material to form a resist mask corresponding to the concavo-convex pattern, a step of etching the first hard mask and the substrate using the resist mask, and forming a concavo-convex pattern region; A step of coating the second hard mask layer and the second resist material in order on the upper surface of the substrate on which the uneven pattern region is formed, and patterning the second resist material to form an auxiliary resist mask corresponding to the auxiliary pattern And a step of etching the second hard mask and the substrate using the auxiliary resist mask to form an auxiliary pattern. And features.

  The invention according to claim 6 is a method for forming a pattern forming body, wherein the imprint mold according to any one of claims 1 to 4 is embossed on a transfer material to form a uniform residual film layer on a transfer substrate. And a step of removing the remaining film layer.

  According to the present invention, the auxiliary pattern is provided in the concavo-convex pattern region so that the amount of remaining film formed when the concavo-convex pattern region is embossed on the transfer material is uniform (constant). Thereby, the amount of the transfer material filled in the uneven pattern region at the time of transfer can be made uniform. Therefore, even when using an imprint mold having a concavo-convex pattern with uneven density, it is possible to form a residual film with a uniform height and to form a pattern with a uniform height even after the residual film is removed. Is possible.

Cross-sectional view for explaining the formation process of a pattern forming body by a conventional optical imprint method Cross-sectional view for explaining transfer material filling Sectional drawing for description which shows the production process of the pattern formation body using the imprint mold concerning the present invention Sectional drawing which shows the process of measuring the volume of the imprint mold which concerns on this invention Sectional drawing for description which shows the manufacturing process of the imprint mold of this invention

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
1. Shape of Imprint Mold As shown in FIG. 3, the imprint mold 130 according to an embodiment of the present invention is for transferring a pattern composed of irregularities onto a transfer material 132.
In the imprint mold 130 according to the present embodiment, uneven patterns 133 and 134 having a density bias for transferring a pattern are mixedly formed on the upper surface of the substrate. Furthermore, the imprint mold 130 of this embodiment has an auxiliary pattern 135 for forming a uniform residual film height and a uniform pattern height after the residual film removal on the transfer material 132 to be transferred on the upper surface of the substrate. Is provided.

The imprint mold 130 according to the present embodiment is not limited to a specific imprint method, and a known imprint method can be widely applied. For example, imprinting methods such as optical imprinting, thermal imprinting, and sol-gel imprinting can be mentioned.
Further, the substrate of the imprint mold 130 can be appropriately selected so as to be suitable for the imprint method to be used. Examples thereof include quartz glass and silicon.

  Further, the uneven patterns 133 and 134 can be designed according to the pattern to be transferred to the transfer material 132. For example, a line & space (Line & Space), a hole, a dot (Hole, Dot) pattern, etc. are mentioned. The step is not limited to a single step and may be a multi-stepped shape.

The auxiliary pattern 135 is a concave pattern provided in the region of the uneven pattern 133 and / or 134. FIG. 3 shows an example in which the auxiliary pattern 135 is provided in the region of the uneven pattern 134. By accommodating a part of the transfer material in the auxiliary pattern 135, the transfer pattern 136 having a uniform residual film height can be formed even if the uneven patterns 133 and 134 having uneven density are pressed onto the transfer material 132. (FIG. 3B). Further, since the remaining film has a uniform height, a pattern 137 having a uniform height can be formed even after the remaining film is removed (FIG. 3C).
The auxiliary pattern 135 is not limited to the position shown in FIG. 3, and can be provided at an arbitrary position in the surface where the imprint mold 130 and the transfer material 132 are in contact with each other.

That is, the imprint mold 130 includes a concavo-convex pattern region having concavo-convex patterns 133 and 134 formed on one surface of the substrate and having an uneven density and auxiliary patterns 135. The concavo-convex patterns 133 and 134 are a combination of concave and convex portions.
The imprint mold 130 forms the transfer pattern 136 corresponding to the concavo-convex patterns 133 and 134 on the transfer material 132 by embossing the concavo-convex patterns 133 and 134 onto the transfer material 132.
The auxiliary pattern 135 is in the region of the concave and convex patterns 133 and 134 and includes a concave portion that accommodates a part of the transfer material 132. The concave portions are formed with a width and height that control the flow amount of the transfer material 132 in the regions of the concave and convex patterns 133 and 134.

2. Method for determining the concave portion formed in the imprint mold Next, a technique of determining the size of the concave portion in the auxiliary pattern 135 formed on the imprint mold according to an embodiment of the present invention will be described with reference to FIG. 4 .
In the following example, a method of determining the auxiliary pattern 135 using the cross-sectional area of the concave portion will be described. However, the auxiliary pattern 135 may be determined using the volume of the concave portion instead of the cross-sectional area. In other words, the width and height of the concave portion are determined based on the volume or area of the transfer material 132 accommodated in the uneven patterns 133 and 134.

As shown in FIG. 4 (a), in the imprint mold 130 of the pattern area P and the pattern height H _1, a concave portion width of the concavo-convex pattern 133 is a high-density regions and S _1, the convex portion width L ₁ To do. Further, when the film thickness of the transfer material 132 laminated on the transfer substrate 131 is h, and the remaining film height to be formed is h ₁ , it can be expressed by the following equation. Note that n is the number of concave portions included in the pattern area P of the uneven pattern 133.
nS ₁ · H ₁ + P · h ₁ = P · h (1)
As shown in FIG. 4 (b), in the imprint mold of the pattern area P and the pattern height H _1, a concave portion width is sparse area concavo-convex pattern 134 and S _2, the convex portion width L ₂ . Further, the film thickness of the transfer material 132 laminated on the transfer substrate 131 and h, and the remaining film height is formed when the h _2, can be represented by a formula shown below. Note that m is the number of concave portions included in the pattern area P of the uneven pattern 134.
mS ₂ · H ₁ + P · h ₂ = P · h (2)
In order to equalize the remaining film height h ₁ and h ₂ in Formula 1 and Formula 2 described above, the auxiliary patterns 135 having a concave portion width S ₃ and the pattern height H _2, sparsely formed in the region of the uneven pattern 134 Then, it can be expressed by the following equation (FIG. 4C).
mS ₂ · H ₁ + P · h ₁ + S ₃ · H ₂ = P · h (3)

Since the imprint mold 130 and the transfer material 132 shown in FIG. 4 are in the same substrate plane, the right sides of the equations (1) and (3) are equal. It can be expressed by a formula. However, this holds true when the condition of H ₁ > H ₂ is satisfied.
S ₃ · H ₂ = nS ₁ · H ₁ − mS ₂ · H ₁ (4)

Arrangement of the auxiliary pattern 135, the height of the concave portion, and the opening size can be arbitrarily provided so as to satisfy the above formula 4.
By controlling the arrangement, height, and opening size of the concave portions of the auxiliary pattern 135 in this way, even if an imprint mold having a concavo-convex pattern with uneven density is brought into contact with the transfer material, the uniform height can be increased. A residual film can be formed.

3. Method for Manufacturing Imprint Mold Next, a method for manufacturing the imprint mold 130 according to an embodiment of the present invention will be described with reference to FIG.
First, as shown in FIG. 5A, a hard mask layer 141 and a resist material 142 are sequentially coated on the upper surface of the substrate 140 (first step). As a method for forming the hard mask layer 141, a known thin film forming method may be used as appropriate depending on the material selected for the hard mask layer 141. For example, a sputtering method or the like is used.

  The substrate 140 may be appropriately selected depending on the application. For example, a silicon substrate, a quartz substrate, a sapphire substrate, an SOI substrate, or the like is used. The hard mask layer 141 may be a material having a high etching selectivity with respect to the selected substrate 140.

  The substrate 140 is preferably a quartz substrate, and the hard mask layer 141 is preferably a layer made of chromium. The quartz substrate is transmissive to general exposure light, particularly when the pattern forming method of the present invention is used for manufacturing processes such as an imprint mold used in the photoimprint method and a photomask. Is preferred. In this case, by using a layer made of chromium as the hard mask layer 141 for the quartz substrate, the etching selectivity of the hard mask layer 141 with respect to the substrate 140 can be set high under general etching conditions. Thereby, in the formation of the concavo-convex resist pattern 143 to be described later, charging (charge-up) of the substrate can be suppressed.

  The resist material 142 may be appropriately selected according to photolithography, electron beam, or the like for patterning. In addition, as a method for forming a coating film of the resist material 142, a known thin film forming technique may be used as appropriate according to the viscosity. For example, a die coating method, a spin coating method, or the like may be used.

  Next, as shown in FIG. 6B, the process proceeds to a patterning process of the resist pattern 143 for unevenness. In this patterning step, the resist material 142 is developed after using an electron beam to form a concavo-convex resist pattern 143 (second step). The development process may be appropriately performed according to the resist film used. Further, a photolithography method may be used.

  Next, as shown in FIG. 5C, the hard mask layer 141 is etched using the concave / convex resist pattern 143 as a mask to form the concave / convex hard mask pattern 144 (third step). Etching in this case may be performed by a known method as appropriate. For example, dry etching or wet etching may be performed. Etching conditions may be adjusted as appropriate according to the resist / substrate used.

  Next, as shown in FIG. 5D, using the concave / convex hard mask pattern 144 as a mask, the substrate 140 is etched from the concave / convex resist pattern 143 side to form a concave / convex pattern on the upper surface of the substrate 140 (fourth). Process). Thereafter, the concave-convex hard mask pattern 144 is removed, thereby producing the concave-convex quartz pattern 145 shown in FIG. 5E (fifth step). As etching in this case, a known etching method may be used as appropriate, and for example, dry etching, wet etching, or the like may be performed. Etching conditions may be adjusted as appropriate according to the hard mask layer / substrate used.

  Subsequently, as shown in FIGS. 5F and 5G, a hard mask layer 141 (sixth step) and a resist material 142 are sequentially coated on the upper surface of the concave-convex quartz pattern 145 (seventh step). Process). The hard mask layer 141 and the resist material are formed in the same manner as in the first step.

Next, as shown in FIG. 5H, the process proceeds to a patterning process of the auxiliary resist pattern 146 (eighth process). This patterning method is the same as in the second step. Further, the region where the auxiliary resist pattern 146 is formed can be provided at an arbitrary position in the surface where the imprint mold and the transfer material are in contact with each other. The opening size of the auxiliary resist pattern, per a concave portion width S ₃ in the formula 4 described above, can optionally be provided so as to satisfy the equation 4.

  Next, as shown in FIG. 5I, the hard mask layer 141 is etched using the auxiliary resist pattern 146 as a mask to form an auxiliary hard mask pattern 147 (ninth step). The method for forming this auxiliary hard mask pattern 147 is the same as in the third step.

Next, as shown in FIG. 5J, using the auxiliary hard mask pattern 147 as a mask, the concave / convex quartz pattern 145 is etched from the auxiliary resist pattern 146 side to form an auxiliary pattern on the upper surface of the concave / convex quartz pattern 145. (Tenth step). Thereafter, by removing the auxiliary hard mask pattern 147, an imprint mold 148 with an auxiliary pattern shown in FIG. 5 (k) is manufactured (11th step). As etching in this case, a known etching method may be used as appropriate, and for example, dry etching, wet etching, or the like may be performed. Etching conditions may be adjusted as appropriate according to the hard mask layer / substrate used.
The height of the auxiliary pattern, per a pattern height H ₂ in the formula 4 described above, can optionally be provided so as to satisfy the equation 4.
The imprint mold of this invention can be manufactured by the above.

4). Method for Forming Pattern Forming Body Using Imprint Mold Next, a method for forming a pattern forming body using an imprint mold according to an embodiment of the present invention will be described with reference to FIG.
First, as shown in FIG. 3A, a transfer material 132 is laminated on a transfer substrate 131, and an imprint mold 130 is disposed facing the transfer material 132. On the imprint mold 130, a dense uneven pattern 133, a sparse uneven pattern 134, and an auxiliary pattern 135 are formed.

  Next, the transfer material 132 and the imprint mold 130 are brought into contact with each other, and the transfer material 132 is cured with UV light. After the curing, the imprint mold 130 is peeled away from the transfer substrate 131 to obtain a transfer pattern 136 having a uniform height having a uniform residual film that is not affected by the density pattern (FIG. 3B).

Since a portion corresponding to the convex portion of the imprint mold 130 remains as a thin resin film on the transfer substrate 131, the remaining film is removed, and a pattern 137 having a uniform height that is not affected by the density pattern is formed. A pattern forming body is obtained (FIG. 3C).
In this case, as a residual film removal method, a known etching method such as an O ₂ RIE method may be used as appropriate, and for example, dry etching may be performed. Etching conditions may be appropriately adjusted according to the transfer material / substrate used.
By the above, the pattern formation body of this invention can be formed.

Hereinafter, an Example is described about the manufacturing method of the imprint mold of this invention mentioned above, and the formation method of a pattern formation body.
[Example 1]
As Example 1, an optical imprint mold was manufactured.
First, a resist material 142 was coated to a thickness of 100 nm on a laminated substrate in which a chromium layer 141 having a thickness of 10 nm was formed as a hard mask layer on a quartz substrate 140 (see FIG. 5A).
Next, after patterning the resist material 142 by irradiating the resist material 142 with an electron beam drawing apparatus, development and rinsing treatment were performed to form an uneven resist pattern 143 having an area of 1000 nm and a Line & Space of 200 nm (FIG. 5 ( see b)).
Next, a chromium pattern (concave / convex hard mask pattern) 144 was formed by dry etching using a chlorine-based mixed gas plasma using the resist pattern 143 for unevenness (see FIG. 5C).
Next, using the chromium pattern 144 as a mask, an uneven quartz pattern 145 having a depth of 200 nm was formed on the quartz substrate 140 by dry etching using a fluorocarbon mixed gas plasma (see FIG. 5D).
Next, the chromium pattern 144 was peeled and washed by wet etching, thereby forming a concavo-convex quartz pattern 145 having a concavo-convex pattern on the quartz substrate 140 (see FIG. 5E).

Subsequently, a resist material 142 was coated to a thickness of 300 nm on a laminated substrate in which a chromium layer 141 was formed to a thickness of 10 nm on the concavo-convex quartz pattern 145 (see FIGS. 5F and 5G).
Next, after patterning the resist material 142 by irradiating the resist material 142 with an electron beam lithography apparatus, development and rinsing were performed to form an auxiliary resist pattern 146 of Line & Space 600 nm (see FIG. 5H). ).
Next, an auxiliary chromium pattern (auxiliary hard mask pattern) 147 was formed by dry etching using a chlorine-based mixed gas plasma using the auxiliary resist pattern 146 as a mask (see FIG. 5I).
Next, using the auxiliary chromium pattern 147 as a mask, an auxiliary quartz pattern having a depth of 135 nm was formed on the quartz pattern 145 for unevenness by dry etching using a fluorocarbon mixed gas plasma (see FIG. 5J).
Next, the auxiliary chrome pattern 147 was peeled and washed by wet etching, thereby forming an optical imprint mold 148 with an auxiliary pattern (see FIG. 5 (k)).
The optical imprint mold 148 was able to be manufactured by the above procedure.

[Example 2]
As Example 2, a pattern forming body was formed using the imprint mold 148 manufactured in Example 1.
First, the transfer material 132 is coated on the transfer substrate 131 to a thickness of 130 nm, and the imprint mold 130 is disposed so as to oppose (see FIG. 3A). On the imprint mold 130, a dense uneven pattern 133, a sparse uneven pattern 134, and an auxiliary pattern 135 are formed.
Next, the transfer material 132 and the imprint mold 130 are brought into contact with each other, and the transfer material 132 is cured with UV light. The imprint mold 130 is peeled away from the transfer substrate 131 to obtain a transfer pattern 136 having a uniform residual film height of 10 nm that is not affected by the dense / dense pattern (see FIG. 3B).
Next, the transfer pattern 136 having a residual film height of 10 nm on the transfer substrate 131 is removed by dry etching using oxygen plasma, and a pattern 137 having a uniform height of 55 nm that is not affected by the density pattern is obtained. The formed pattern formed body was obtained (see FIG. 3C).
From the above, the pattern forming body of the present invention can be formed.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention at the implementation stage. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.
For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the effect of the invention can be obtained. In the case where it is possible, this constituent requirement can be extracted as a constituent invention.

  A pattern forming method and a pattern forming body according to the present invention include a semiconductor device, an optical element, a wiring circuit, a data storage medium (hard disk, optical medium, etc.), a medical member (analysis test chip, microneedle, etc.), a biodevice (bio Sensors, cell culture substrates, etc.), precision inspection equipment members (inspection probes, sample holding members, etc.), display panels, panel members, energy devices (solar cells, fuel cells, etc.), microchannels, microreactors, MEMS devices, etc. It can be expected to be usefully used for forming a fine pattern used in the manufacturing method.

110, 120, 130 ... Imprint mold 111, 121, 131 ... Transfer substrate 112, 122, 132 ... Transfer material 113 ... UV light 114, 125, 136 ... Transfer pattern 115, 126, 137 ... Pattern 123 after residual film removal, 133 ... Concave and convex pattern 124, 134 ... Concave and convex pattern 135 in sparse area ... Auxiliary pattern 140 ... Quartz substrate 141 ... Hard mask layer 142 ... Resist material 143 ... Concave resist pattern 144 ... Concave and convex hard mask pattern 145 ... Concave and convex Quartz pattern 146 ... Auxiliary resist pattern 147 ... Auxiliary hard mask pattern 148 ... Optical imprint mold with auxiliary pattern

Claims (6)

A concave / convex pattern region having a concave / convex pattern formed by a combination of a concave portion and a convex portion formed on one surface of the substrate, and the concave / convex pattern region on the transfer material by embossing the concave / convex pattern region on the transfer material on the transfer substrate. An imprint mold for forming a transfer pattern corresponding to the pattern,
An imprint mold, wherein an auxiliary pattern is provided in the concavo-convex pattern region so that a residual film layer formed when the concavo-convex pattern region is embossed on the transfer material is uniform.   The imprint mold according to claim 1, wherein the auxiliary pattern includes a concave portion that accommodates a part of the transfer material in the uneven pattern region.   The imprint mold according to claim 2, wherein the concave portion of the auxiliary pattern is formed with a width and a depth that control a flow amount of the transfer material in the concave / convex pattern region.   The width and the depth of the concave portion of the auxiliary pattern are determined based on a volume of the transfer material accommodated in the concave / convex pattern or an area of the concave / convex pattern. Print mold. A method for producing an imprint mold according to any one of claims 1 to 4,
Coating the first hard mask layer and the first resist material in sequence on the upper surface of the substrate;
Patterning the first resist material to form a resist mask corresponding to the concavo-convex pattern;
Etching the first hard mask and the substrate using the resist mask to form the concavo-convex pattern region;
Coating the second hard mask layer and the second resist material in order on the upper surface of the substrate on which the uneven pattern region is formed;
Patterning the second resist material to form an auxiliary resist mask corresponding to the auxiliary pattern;
And a step of etching the second hard mask and the substrate using the auxiliary resist mask to form the auxiliary pattern. A method for forming a pattern forming body, comprising:
A step of embossing the imprint mold according to any one of claims 1 to 4 on the transfer material to form a uniform residual film layer on the transfer substrate;
And a step of removing the remaining film layer.

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