JP2018126930A - Transferring method and thermal nano-imprinting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transferring method and thermal nano-imprinting apparatus in which, by using a thermal nano-imprinting method, interposition of foreign matter can be reduced as compared with the conventional method and the production efficiency can be improved as well as shortening of the tact time can be achieved.SOLUTION: The transferring method of the present invention includes a peeling step for peeling off the protective film from a fine pattern forming sheet and a bonding step for bonding, after the peeling step, the surface of the first mask layer from which protective film is peeled off and is exposed, toward the surface of the object to be treated, and is characterized in that suction is carried out while peeling the protective film with the suction port directed toward the peeling position.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a transfer method and a thermal nanoimprint apparatus.

  Patent Document 1 discloses a transfer method using a thermal nanoimprint apparatus. In the thermal nanoimprint method, for example, as shown in FIG. 2 of Patent Document 1, a cover film 10 having a concave-convex structure 11 formed on a concave surface is prepared. Then, the second mask layer 12 for patterning the first mask layer is filled in the recess 11 a of the cover film 10, and the first mask so as to cover the second mask layer 12 and the concavo-convex structure 11. Layer 13 is filled. Then, a protective film 14 is provided on the surface of the first mask layer 13. In this manner, a fine pattern forming sheet is produced.

  For example, in the transfer step shown in FIG. 20 of Patent Document 1, first, the protective film 601 is peeled from the fine pattern forming sheet 101. Thereafter, the first mask layer surface of the fine pattern forming sheet 101 and the surface to be processed of the object to be processed 104 are pressed and bonded together.

Japanese Patent No. 5560377

  However, as described above, when the protective film 601 is peeled from the fine pattern forming sheet 101, the foreign matter (film piece) accompanying the peeling is electrostatically drawn into both ends of the first mask layer.

  As a result, the first mask layer of the fine pattern forming sheet and the object to be processed are bonded together through the foreign matter. At this time, the presence of foreign matter causes air around the foreign matter to be stuck and bonded, and a defect several times as large as the foreign matter occurs between the first mask layer and the object to be processed. The rate (yield) decreases.

  Moreover, if the protective film is slowly peeled off, the generation of foreign matter can be improved to some extent. However, there is a problem that the tact time increases.

  The present invention has been made in view of the above points, and by using a thermal nanoimprint method, it is possible to reduce the presence of foreign matter and improve the production efficiency as compared with the prior art, and the tact time can be improved. It is an object of the present invention to provide a transfer method and a thermal nanoimprint apparatus that can be shortened.

  The transfer method according to the present invention includes a cover film having a nanoscale concavo-convex structure formed on one surface, a second mask layer provided inside the concave portion of the concavo-convex structure, the concavo-convex structure, and the second A fine pattern forming sheet comprising a first mask layer provided so as to cover the mask layer and a protective film covering the surface of the first mask layer is used, and the first pattern is formed on the object to be processed. A transfer method for transferring and applying the mask layer and the second mask layer, the transfer method including a peeling step of peeling the protective film from the fine pattern forming sheet, and the protective film after the peeling step A bonding step of bonding the surface of the first mask layer exposed by peeling to the surface of the object to be processed, and peeling the protective film with the suction port facing the peeling position While sucking And performing.

  In the present invention, it is preferable to perform suction with the suction port directed toward both ends of the peeling position.

  Further, the thermal nanoimprint apparatus according to the present invention includes a cover film having a nanoscale uneven structure formed on one surface thereof, a second mask layer provided inside the recess of the uneven structure, the uneven structure, and the Using a fine pattern forming sheet comprising a first mask layer provided so as to cover the second mask layer and a protective film covering the surface of the first mask layer, on the object to be processed A thermal nanoimprint apparatus for transferring and applying the first mask layer and the second mask layer, the peeling part for peeling the protective film from the fine pattern forming sheet, and peeling the protective film A bonding unit for bonding the exposed surface of the first mask layer toward the surface of the object to be processed, and a suction device having a suction port directed to a peeling position is provided. That.

  In this invention, it is preferable that the suction port of the said suction device is orient | assigned to the both ends of the said peeling position.

  According to the present invention, by using the thermal nanoimprint method, when the surface of the first mask layer of the fine pattern forming sheet is bonded to the surface of the object to be processed, the inclusion of foreign matters can be reduced. It is possible to improve the production efficiency and shorten the tact time.

It is a cross-sectional schematic diagram which shows the sheet | seat for fine pattern formation which concerns on this Embodiment. It is process drawing for demonstrating the method of forming a fine pattern with respect to a to-be-processed object using the sheet | seat for fine pattern formation which concerns on this Embodiment. It is process drawing for demonstrating the method of forming a fine pattern with respect to a to-be-processed object using the sheet | seat for fine pattern formation which concerns on this Embodiment. It is a fragmentary perspective view for demonstrating the attraction | suction apparatus of this embodiment. It is process drawing for demonstrating the method of forming a fine pattern with respect to a to-be-processed object using the sheet | seat for fine pattern formation which concerns on this Embodiment. It is process drawing for demonstrating the method of forming a fine pattern with respect to a to-be-processed object using the sheet | seat for fine pattern formation which concerns on this Embodiment. It is a cross-sectional schematic diagram regarding bonding of the fine pattern forming sheet and the object to be processed according to the present embodiment. It is a schematic diagram which shows the thermal nanoimprint apparatus which concerns on this Embodiment.

  Hereinafter, an embodiment of the present invention (hereinafter referred to as “embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

<Outline of fine pattern forming sheet and thermal nanoimprint method (transfer method)>
First, the outline | summary of the sheet | seat for fine pattern formation which concerns on this Embodiment is demonstrated.

  In the thermal nanoimprint method of the present invention, a fine pattern forming sheet described below is used. Thereby, thermal nanoimprinting at low temperature and low pressure can be performed with high accuracy.

  The fine pattern forming sheet according to the present embodiment is a film in which the second mask layer and the first mask layer are formed on the concavo-convex structure of the cover film in which the concavo-convex structure is formed on one surface. . FIG. 1 is a schematic cross-sectional view showing a fine pattern forming sheet according to the present embodiment. As shown in FIG. 1, the fine pattern forming sheet I is provided with a resin layer 3 on the surface of the cover film 2. An uneven structure 3 a is formed on the surface of the resin layer 3 opposite to the surface in contact with the cover film 2. In the following description, when the cover film 2 is simply referred to, the resin layer 3 on which the concavo-convex structure 3a is formed is also included. The second mask layer 4 is filled in the recesses of the concavo-convex structure 3a. The first mask layer 5 is formed so as to cover the second mask layer 4 and the concavo-convex structure 3a. As shown in FIG. 1, a protective film 6 is provided on the first mask layer 5.

  In addition, in the bonding part attached to the thermal nanoimprint apparatus demonstrated later, the surface bonded to a to-be-processed object is the surface of the 1st mask layer 5. FIG. The film peeled off at the peeling portion is the protective film 6, and the film released at the release portion is the cover film 2. According to the transfer method of the present embodiment, the concavo-convex structure composed of the first mask layer 5 and the second mask layer 4 is transferred onto the object to be processed.

  2A to 2C and FIGS. 3A to 3F are process diagrams for explaining a method of forming a fine pattern on an object to be processed using the fine pattern forming sheet according to the present embodiment. As shown in FIG. 2A, the cover film 10 has a concavo-convex structure 11 formed on the main surface thereof. The concavo-convex structure 11 includes a plurality of concave portions 11a and convex portions 11b. The cover film 10 is, for example, a film-shaped or sheet-shaped molded body.

  First, as shown in FIG. 2B, a second mask layer 12 for patterning a first mask layer to be described later is filled in the recess 11 a of the concavo-convex structure 11 of the cover film 10. The second mask layer 12 is made of, for example, a sol-gel material. Here, the laminated body provided with the cover film 10 and the second mask layer 12 is referred to as a first fine pattern forming sheet I or simply as a first laminated body I.

  Next, as shown in FIG. 2C, a first mask layer 13 is formed on the concavo-convex structure 11 including the second mask layer 12 of the first stacked body I. The first mask layer 13 is used for patterning an object to be processed which will be described later. The first mask layer 13 is made of, for example, a photocurable resin, a thermosetting resin, or a thermoplastic resin.

  Further, as shown in FIG. 2C, a protective film 14 is provided on the upper side of the first mask layer 13. The protective film 14 protects the first mask layer 13. Here, the laminate composed of the cover film 10, the second mask layer 12, and the first mask layer 13 is referred to as a second fine pattern forming sheet II or simply as a second laminate II. This 2nd laminated body II can be used for the patterning of a to-be-processed object by bonding the 1st mask layer 13 to a to-be-processed object.

  Next, a workpiece 20 as shown in FIG. 3A is prepared. The object 20 is, for example, a flat inorganic substrate, such as a sapphire substrate, a SiC (silicon carbide) substrate, a Si (silicon) substrate, a spinel substrate, or a nitride semiconductor substrate. As shown in FIG. 3B, the exposed surface of the first mask layer 13 of the second stacked body II is bonded to the main surface of the target object 20 so as to face the main surface of the target object 20. As a result, the 3rd laminated body III comprised by the 2nd laminated body II and the to-be-processed body 20 is obtained. Bonding is, for example, lamination, and thermal lamination is particularly suitable. This operation is performed in the bonding part of the thermal nanoimprint apparatus described later.

  Next, as shown in FIG. 3C, the cover film 10 is released from the first mask layer 13 and the second mask layer 12. As a result, an intermediate body 21 including the object to be processed 20, the first mask layer 13, and the second mask layer 12 is obtained. This operation is performed in the mold release part of the thermal nanoimprint apparatus described later.

  Further, the second laminated body II is unwound by a feeding roller which will be described later, and is wound by a winding roller which will be described later. That is, the pasting is performed in the downstream of the second laminated body II in the flow direction rather than the feeding roller, and the mold release is performed in the downstream of the past in the flow direction and the upstream of the take-up roller.

  Furthermore, a to-be-processed object can move with conveyance of the 2nd laminated body II between the said bonding and mold release. In other words, the second stacked body II functions as a carrier for the object to be processed.

  In addition, between the bonding mentioned above and mold release, the 1st mask layer 13 may be hardened or solidified by irradiating an energy beam with respect to the 2nd laminated body II. Further, the first mask layer 13 may be cured or solidified by heat applied during bonding and pressing. Moreover, after irradiating energy rays with respect to the 2nd laminated body II and hardening or solidifying the 1st mask layer 13, the 3rd laminated body III is heated, The 1st mask layer 13 Stability may be improved. Furthermore, the first mask layer 13 may be cured or solidified by energy beam irradiation or heat treatment after release. Since these operations are performed between bonding and mold release, they are performed in a state where the pressure applied at the time of bonding is released. In particular, in the step of performing bonding and subsequently irradiating energy rays, the pressure at the time of bonding is released during energy ray irradiation.

  The obtained intermediate 21 is recovered by the recovery unit, temporarily stored, or immediately sent to the process described below.

  The intermediate body 21 recovered by the recovery unit is transported to another apparatus different from the thermal nanoimprint apparatus. Then, using the second mask layer 12 as a mask, the first mask layer 13 is patterned by oxygen ashing, for example, as shown in FIG. 3D. As a result, the fine mask structure 16 provided with the fine mask pattern 16a having the high aspect ratio and constituted by the first mask layer 13 and the second mask layer 12 is obtained. Further, using the patterned first mask layer 13 as a mask, the object to be processed 20 is subjected to, for example, reactive ion etching, and a fine pattern 22 is formed on the main surface of the object to be processed 20 as shown in FIG. 3E. Form. Finally, as shown in FIG. 3F, the first mask layer 13 remaining on the main surface of the object to be processed 20 is removed to obtain the object to be processed 20 having the fine pattern 22.

  In the present embodiment, the process up to obtaining the second laminate II from the cover film 10 shown in FIGS. 2A to 2C is performed in one line (hereinafter referred to as the first line). The subsequent steps from FIG. 3A to FIG. 3F are performed on another line (hereinafter referred to as a second line). In a more preferred embodiment, the first line and the second line are performed in separate facilities. For this reason, the 2nd laminated body II is packaged by making the 2nd laminated body II into a scroll shape (roll shape), and is stored or conveyed.

  As described above, the second stacked body II mainly ensures the fine pattern accuracy of the first mask layer 13 and the second mask layer 12 and the film thickness accuracy of the first mask layer 13. The fine pattern 22 can be provided on the object 20 with high accuracy within the surface of the object 20. Here, when the first mask layer 13 of the second laminated body II is bonded to the object to be processed 20, the second laminated body II is bent, air voids are generated, When mixed, the in-plane accuracy of the fine pattern 22 provided on the workpiece 20 is greatly reduced. Furthermore, excessive stress is applied to the fine patterns of the first mask layer 13 and the second mask layer 12 when the cover film 10 is peeled from the laminate comprising the second laminate II / the object to be processed 20. In some cases, or when the second stacked body II is twisted, cohesive failure of the first mask layer 13, interfacial peeling between the first mask layer 13 and the target object 20, the first mask layer 13 and the second mask layer 13 There arises a problem of defective release of the mask layer 12 and the cover film 10.

  By the way, generation | occurrence | production of the air void which arises when bonding the 1st mask layer 13 of the 2nd laminated body II to the to-be-processed object 20 is when the protective film 14 peels from the 2nd laminated body II. The reason is that particles (foreign matter) derived from the protective film 14, the first mask layer 13, the second mask layer 12, and the cover film 10 are drawn into both ends of the first mask layer 13. The particles move to both upper ends of the first mask layer 13 due to static electricity generated by peeling charging. An air void becomes a defect several tens of times larger than a particle by biting air by mixing particles.

  In order to suppress the peeling charge, it has been found that even if the charge is removed by aiming at the peeled portion between the protective film and the first mask layer, the removal of the particles is insufficient.

  Therefore, the present inventors sucked particles (foreign matter) derived from the protective film 14, the first mask layer 13, the second mask layer 12, and the cover film 10 at the time of peeling, so that the second laminated body. The first mask layer 13 of II and the object to be processed 20 can be bonded without interposing foreign matters.

<Suction device>
In the present embodiment, the suction port of the suction device is directed to the peeling position between the protective film 14 and the first mask layer 13 of the second laminate II, and suction is performed while peeling the protective film 14. Then suck the particles. Here, the particles are not limited to those derived from the protective film 14, the first mask layer 13, the second mask layer 12, and the cover film 10, but are described as representative. That is, the particles and foreign matters to be sucked may include those other than those derived from the protective film 14, the first mask layer 13, the second mask layer 12, and the cover film 10. The same applies hereinafter.

  As shown in FIG. 4, in the present embodiment, the suction ports 606 a and 606 b of the suction device 606 are directed to the position where the protective film 14 is peeled from the second laminate II.

  The “peeling position” refers to a portion between the protective film 14 immediately after peeling and the first mask layer 13 of the second laminate II from which the protective film 14 has been peeled off.

  As shown in FIG. 4, the protective film 14 is peeled from the second laminated body II by the peeling roller 602, and the second laminated body II is sent to the bonding process with the object to be processed. As shown in FIG. 4, the pair of suction ports 606 a and 606 b of the suction device 606 is directed to both ends of the peeling position. At this time, the pair of suction ports 606 a and 606 b are preferably directed to both ends of the surface of the first mask layer 13 exposed by peeling off the protective film 14.

  According to the present embodiment, particles (foreign matter) derived from the protective film 14 generated when the protective film 14 is peeled can be appropriately sucked by the suction ports 606a and 606b of the suction device 606.

  In this way, by sucking in the foreign matter when the protective film 14 is peeled off, it is possible to suppress the occurrence of air void defects at the time of subsequent bonding with the object to be processed. Therefore, according to the present embodiment, the production efficiency ( (Yield) can be improved.

  Moreover, suppression of the foreign material mixing at the time of peeling of the protective film 14 originates in the protective film 14 drawn into the both ends of the 2nd laminated body II (1st mask layer 13) by peeling the protective film 14 slowly. The number of particles can be suppressed to some extent, but the tact time increases. On the other hand, according to the present embodiment, since the particles are directly sucked while peeling off the protective film 14, it is not necessary to peel off the protective film 14 slowly, and the tact time can be shortened.

  As shown in FIG. 4, the suction ports 606a and 606b can be expected to remove particles to some extent by increasing the suction force even if they are directed to both ends of the peeling position. However, since it is confirmed by particle measurement that particles are generated from both ends of the peeling roller portion 602, it is preferable that the suction ports 606a and 606b be directed to both ends of the peeling position because the particles can be effectively removed. .

  The suction force of the suction device 606 is not particularly limited, but is preferably about 0.1 to 30.0 (m / s), for example. By setting the suction force to 0.1 (m / s) or more, there is an effect of removing particles. Moreover, by making suction | attraction force into 30.0 (m / s) or less, flapping with the protective film at the time of peeling and the sheet | seat for fine pattern formation can be suppressed, and conveyance can be performed appropriately. On the other hand, if the suction force is 30.0 (m / s) or more, the airflow in the apparatus is disturbed, and conversely, particles may increase excessively.

In addition, as the shape of the suction port, a circular shape, an elliptical shape, a rectangular shape including rounded corners such as a nozzle, and the like can be presented. Moreover, it is preferable that the magnitude | size (caliber) of a suction port is about 0.5-2500 mm < ² >. When the suction port is not a circular diameter, for example, it can be obtained by an average value of the length and width. By setting the size of the suction port to 0.5 mm ² or more, there is an effect of removing particles. Further, by setting the size of the suction port to 2500 mm ² or less, flapping between the protective film and the fine pattern forming sheet at the time of peeling can be suppressed, and conveyance can be performed appropriately. On the other hand, when the size of the suction port is 2500 mm ² or more, the airflow in the apparatus is disturbed, and conversely, particles may increase excessively.

The air volume is a value obtained by multiplying the product of the size of the suction port and the wind speed by a time term, and is about 3 × 10 ^{−6 to} 4.5 (m ³ / min) from the minimum value and the maximum value. It is preferable.

<Mask pattern transfer process>
Next, each process using the fine pattern forming sheet will be described. The method of forming the fine pattern 22 on the object 20 is divided into a mask pattern transfer process and an etching process.

  5 and 6 are process diagrams for explaining a method of forming a fine pattern on an object to be processed using the fine pattern forming sheet according to the present embodiment. The mask pattern transfer process is shown in FIGS. 5A and 5B and FIGS. 6B to 6C.

  The mask pattern transfer process includes at least a bonding process (pressing process), an energy beam irradiation process, and a release process in this order, and the bonding process (pressing process) and the energy beam irradiation process are performed independently. Features. Here, a press process is implemented by the bonding part of the thermal nanoimprint apparatus which concerns on this Embodiment. Further, the mold release step is performed by a peeling unit and a fixing unit of the thermal nanoimprint apparatus according to the present embodiment.

  The second laminate II shown in FIG. 5A includes a cover film 10 composed of a support base material 10a and a resin layer 10b, and a concavo-convex structure 11 formed in the resin layer 10b of the cover film 10 filled in the second laminate II. 2 mask layers 12 and a first mask layer 13 provided on the concavo-convex structure 11 including the second mask layer 12. When the protective film 14 is provided on the surface of the first mask layer 13 of the second laminate II, first, remove the protective film 14 from the second laminate II, as shown in FIG. The surface of the first mask layer 13 is exposed.

  In the present embodiment, as described above, when the protective film 14 is peeled from the second laminate II, the particles (foreign matter) drawn into both ends of the first mask layer 13 are sucked by the suction device. Yes.

(Bonding process (pressing process))
In the bonding step, as shown in FIG. 6A, the second stacked body II and the processed body 20 are pressed by pressing the second stacked body II against the processed body 20 via the first mask layer 13. Are bonded together to obtain a third laminate III. At this time, the second stacked body II and the target object 20 are brought into close contact with each other by being pressed while being heated. The second stacked body II is used for the purpose of bonding the object to be processed 20 and the first mask layer 13.

  When a thermocompression-bondable resin is selected as the first mask layer 13, it is preferable to perform heating during pressing in order to increase the fluidity of the first mask layer 13. This heating is preferably performed at least from the surface of the workpiece 20 and the heating temperature is preferably 60 ° C to 200 ° C.

(Bonding)
Entrainment of the environmental atmosphere at the time of bonding reduces the ratio (transfer rate) of the second mask layer 12 and the first mask layer 13 that is transferred to the object to be processed 20. For this reason, the problem according to the use of the to-be-processed object 20 generate | occur | produces. For example, when an object to be processed is used as a substrate for an LED, micro entrainment of oxygen (oxygen in the air) at the time of bonding (involvement of an environmental atmosphere of a nanometer to several tens of micrometer scale) is an LED semiconductor. In some cases, defects in the crystal layer are introduced to deteriorate the light emission characteristics of the LED or increase the leakage current. Moreover, macro entrainment at the time of bonding (bubbles on the order of several tens of micrometers to millimeters) becomes a large defect, leading to a decrease in yield when a highly efficient LED is manufactured. Therefore, when bonding the 1st mask layer 13 to the to-be-processed object 20, it is preferable to employ | adopt either the method shown to the following (1)-(4), or these composite methods.

  In addition, as already described, in this Embodiment, the particle derived from the protective film which arises when a protective film is peeled in the step before bonding is removed.

(1) Bonding is performed in a low oxygen atmosphere. By reducing the oxygen concentration, the curability of the first mask layer 13 can be kept good even when an environmental atmosphere is involved in the interface between the first mask layer 13 and the object 20 to be processed. Therefore, the transfer accuracy can be improved. The low oxygen atmosphere can be produced by vacuum (reduced pressure), introduction of a gas typified by N ₂ gas or Ar gas, introduction of a compressible gas typified by pentafluoropropane or carbon dioxide, or the like. In particular, by adopting a vacuum (reduced pressure) environment, the bonding property can be improved.

  FIG. 7 is a schematic cross-sectional view relating to bonding of the fine pattern forming sheet and the object to be processed according to the present embodiment. 7A to 7C, for the sake of convenience, in order to express the first stacked body I and the second stacked body II as the same schematic diagram, the surface of the concavo-convex structure 11 of the first stacked body I is illustrated. The unevenness is omitted and shown as a flat shape. In the second stacked body II shown in FIGS. 7A to 7C, the first mask layer 13 is provided on the surface side to be bonded to the object to be processed 20, and the first mask layer 13 is formed on the object to be processed 20. It comes to contact.

  (2) As shown in FIG. 7A, there is a method in which the second stacked body II is brought into contact with the workpiece 20 from one end portion toward the other end portion, and the contact area is gradually increased. . In this case, compared with parallel plate type bonding, an environmental atmosphere escape path is created, so that the inclusion of the environmental atmosphere is reduced. Therefore, the malfunction which an air void produces in the interface of the 2nd laminated body II and the to-be-processed object 20 can be suppressed appropriately by the synergistic effect with the reduction effect of particle mixing.

  (3) As shown in FIG. 7B, the vicinity of the center of the second stacked body II is deformed downward and the second stacked body II is brought into contact with the workpiece 20 in that state, One method is to undo the deformation. In this case, compared with parallel plate type bonding, an environmental atmosphere escape path is created, so that the inclusion of the environmental atmosphere is reduced. Therefore, the malfunction which an air void produces in the interface of the 2nd laminated body II and the to-be-processed object 20 can be suppressed appropriately by the synergistic effect with the reduction effect of particle mixing.

  (4) As shown in FIG. 7C, the second laminated body II is curved, and the second laminated body II is brought into contact from one end thereof to the other end, and bonded in the manner of lamination. The technique to do is mentioned. In this case, compared with parallel plate type bonding, an environmental atmosphere escape path is created, so that the inclusion of the environmental atmosphere is reduced. Therefore, the malfunction which an air void produces in the interface of the 2nd laminated body II and the to-be-processed object 20 can be suppressed appropriately by the synergistic effect with the reduction effect of particle mixing. This is particularly effective when the cover film of the second laminate II is a flexible mold.

(Energy beam irradiation process)
In the energy ray irradiation step, as shown in FIG. 6B, the layered body III to which the second layered body II and the object to be processed 20 are bonded is irradiated with energy rays in a state where the pressure during bonding is released. Then, the first mask layer 13 is cured. This eliminates the need to cure while pressing the first mask layer 13 as in the prior art, so the pressing step and the energy ray irradiation step can be performed independently, and in the manufacture of the concavo-convex structure 40 described later. Process management becomes easy.

  In addition, the energy ray irradiation process improves the stability of the second mask layer 12 and the first mask layer 13 and greatly improves the interface adhesion between the second mask layer 12 and the first mask layer 13. The purpose is to let you. Furthermore, in the case of the second stacked body II, it is also an object to bond the first mask layer 13 and the object to be processed 20.

  Energy beam irradiation is effective when a chemical bond based on a chemical reaction is generated at the interface between the second mask layer 12 and the first mask layer 13. The type of energy rays can be appropriately selected depending on the composition of the second mask layer 12 and the first mask layer 13, and is not particularly limited. Examples thereof include X-rays, UV, and IR. Moreover, it is preferable to irradiate the energy beam from at least one of the second stacked body II side and the workpiece 20 side. In particular, when at least a part of the second stacked body II or the workpiece 20 is an energy ray absorber, it is preferable to irradiate the energy rays from the medium side that transmits the energy rays.

Integrated quantity of light when the energy ray irradiation is preferably 500~5000mJ / cm ^2, more preferably 800~2500mJ / cm ^2. Two or more energy ray sources having different emission wavelength ranges may be selected.

  In addition, it is possible to increase the film thickness of the first mask layer 13 by performing the energy ray irradiation process in a state in which the pressure is released after the second stacked body II is pressed against the workpiece 20. By passing through an etching process described later, it becomes possible to transfer a mask having a high aspect ratio to the object 20 to be processed.

(Release process)
In the mold release step, as shown in FIGS. 6B and 6C, the cover film 10 is removed from the second stacked body II bonded to the target object 20 in the third stacked body III. As a result, an intermediate body 21 including the object to be processed 20, the first mask layer 13, and the second mask layer 12 is obtained.

  As described above, the concavo-convex structure is transferred to the object to be processed 20 using the second stacked body II by the mask pattern transfer process according to the present embodiment, and the surface of the object to be processed 20 as shown in FIG. 6D. A fine mask structure 16 having the first mask layer 13 and the second mask layer 12 provided thereon is obtained. At this time, the first mask layer 13 can be formed thick on the object to be processed 20, and a mask pattern having a high aspect ratio can be formed on the object to be processed 20 through an etching process described later. It becomes possible.

  Furthermore, it is preferable to add a heating process between the energy beam irradiation process and the mold release process in the mask pattern transfer process. That is, the mask pattern transfer process may be configured to undergo a pressing process, an energy beam irradiation process, a heating process, and a release process in this order.

(Heating process)
By adding a heating step after the energy beam irradiation, the stability of the second mask layer 12 and the first mask layer 13 is improved, depending on the composition of the second mask layer 12 and the first mask layer 13. In addition, an effect of reducing transfer failure during the mold release process, particularly cohesive failure of the first mask layer 13 can be obtained. The heating temperature is preferably in the range of approximately 40 ° C. to 200 ° C. and lower than the glass transition temperature Tg of the second mask layer 12 and the first mask layer 13. Further, the heating time is preferably approximately 5 seconds to 60 minutes, and most preferably 5 seconds to 3 minutes from the viewpoint of improving transfer accuracy and improving industrial production. Note that the heating step may be performed in a low oxygen atmosphere.

  After the heating step, the laminate composed of the cover film 10 / the first mask layer 13 / the object to be processed 20 is preferably cooled to 5 to 80 ° C., more preferably 18 to 30 ° C. It is preferable to move to a mold release step. In addition, about a cooling method, if a laminated body is cooled in the said temperature range, it will not specifically limit.

  Further, a post-processing step may be added after the release step in the mask pattern transfer step. That is, the mask pattern transfer process may be configured to undergo a pressing process, an energy beam irradiation process, a mold release process, and a post-processing process in this order, and the pressing process, the energy beam irradiation process, the heating process, the mold release process, and the post process. It is good also as a structure which passes a process process in this order.

(Post-processing process)
The post-processing step is performed by irradiating energy rays from both or one of the second mask layer 12 side and the target object 20 side of the fine mask structure 16 shown in FIG. 6D. In addition, the post-processing step is performed by performing both heating and / or energy beam irradiation on the fine mask structure 16.

  By irradiating energy rays, the reaction of the unreacted components contained in both or either of the second mask layer 12 and the first mask layer 13 can be promoted, and the second mask layer 12 and This is preferable because the stability of the first mask layer 13 is improved, and the remaining film processing step of the second mask layer 12, the etching step of the first mask layer 13, and the etching step of the object to be processed 20 can be performed satisfactorily. Examples of energy rays include X-rays, UV, and IR. Further, it is preferable to irradiate the fine mask structure 16 from at least one of the second mask layer 12 side and the target object 20 side with respect to the energy mask. In particular, it is preferable to irradiate from the second mask layer 12 side.

<Etching process>
The intermediate body 21 is produced by peeling the cover film 10 after the second laminated body II is bonded to the body 20 to be processed, the second mask layer 12 / the first mask layer 13 / the body to be processed. The details of the manufacturing method are as already described in the mask pattern transfer step. Here, the fine mask structure 16 can be manufactured by etching the intermediate 21 as shown in FIG. 6D. Further, by performing etching on the fine mask structure 16 as shown in FIGS. 6E and 6F, the fine pattern 22 can be formed on the object 20 to be processed, and the concavo-convex structure 40 can be obtained.

  A method of processing the intermediate body 21 into the fine mask structure 16 is etching of the first mask layer 13 using the second mask layer 12 as a mask. Thereby, the fine mask structure 16 provided with the fine mask pattern 16a having a high aspect ratio, which is constituted by the first mask layer 13 and the second mask layer 12, is obtained.

<Thermal nanoimprinting device>
Next, the thermal nanoimprint apparatus according to the present embodiment will be described.
FIG. 8 is a schematic diagram showing a thermal nanoimprint apparatus according to the present embodiment. The thermal nanoimprint apparatus 200 according to the present embodiment includes a feed roller 202 around which a long fine pattern forming sheet 101 is wound.

  The delivery roller 202 delivers the fine pattern forming sheet 101 at a predetermined speed. A take-up roller 203 that winds the sent fine pattern forming sheet 101 is provided in a pair with the feed roller 202. The rotation speed of the take-up roller 203 and the rotation speed of the feed roller 202 may be controlled so that the feed speed and the take-up speed of the fine pattern forming sheet 101 are synchronized. In order to control the tension, a dancer roller, a torque motor, a tension controller, or the like can be used. Therefore, the transport mechanism for the fine pattern forming sheet 101 can be appropriately designed according to the tension control method employed. A driving unit can be connected to each of the feed roller 202 and the take-up roller 203.

(Peeling of protective film)
As shown in FIG. 8, a separation roller unit 602 that separates the protective film 601 from the fine pattern forming sheet 101 is provided downstream of the feed roller 202 in the flow direction MD of the fine pattern forming sheet 101. When a dancer roller is installed in the vicinity of the feed roller 202, the peeling roller unit 602 is provided downstream of the dancer roller in the flow direction MD of the fine pattern forming sheet 101. The peeling roller unit 602 is provided with a winding roller 603 that winds up and collects the protective film 601 at a subsequent stage in the flow direction of the protective film 601. The peeling roller unit 602 is not particularly limited as long as it can peel the protective film 601 from the fine pattern forming sheet 101, whether it is a free roller without a driving unit or a roller with a driving unit. On the other hand, since the take-up roller 603 plays a role of taking up and collecting the protective film 601 peeled off from the fine pattern forming sheet 101, it is preferable to attach a drive unit. The take-up roller 603 rotated by the drive unit may be synchronized with the speed of the fine pattern forming sheet 101 fed from the feed roller 202, and suppresses conveyance failure such as bending or meandering of the fine pattern forming sheet 101. In order to control the tension of the fine pattern forming sheet 101, a torque motor can be used to drive the take-up roller 603, or a dancer roller can be installed between the take-up roller 603 and the peeling roller unit 602. . A constant tension can be applied to the protective film 601 by providing a torque motor and a dancer roller.

  As shown in FIG. 8, a suction device 606 is disposed in the vicinity of the peeling roller unit 602. And while peeling the protective film 601, the both ends of a peeling position are attracted | sucked with a suction device, and the particle derived from the protective film 601 is removed.

  Further, when the peeling roller unit 602 is provided at a position close to the rotating body 102 of the bonding unit 201, in addition to the above-described particle removal, the foreign matter on the surface of the fine pattern forming sheet 101 which is peeled off and exposed from the protective film 601 Can be effectively suppressed, and as a result, the bonding accuracy between the fine pattern forming sheet 101 and the surface of the workpiece 104 is improved, which is preferable.

  A bonding unit 201 is provided further downstream in the flow direction MD than the feed roller 202. The bonding unit 201 includes a pressing unit 100 including a rotating body 102. In the present embodiment, the surface layer of the rotating body 102 is made of silicone rubber. As the silicone rubber, one having a glass transition temperature Tg of 20 ° C. or lower was employed. Moreover, the static elimination machine (not shown) which removes static electricity from the bonding atmosphere was installed separately.

  The rotating body 102 extends over the width direction of the fine pattern forming sheet 101. The cross-sectional shape of the rotating body 102 is a substantially perfect circle. The length of the rotating body 102 in the width direction of the fine pattern forming sheet 101 is not particularly limited as long as it is larger than the size of the object 104 to which the fine pattern forming sheet 101 is bonded. For example, it is slightly over 2 inches, over 4 inches, over 6 inches, or over 8 inches. Further, in order to arrange a plurality of objects to be processed 104 in the width direction of the fine pattern forming sheet 101 and simultaneously paste the fine pattern forming sheet 101 to the object to be processed 104, the rotating body 102 is a fine pattern forming sheet. 101 is preferably extended over the entire width direction. In the present embodiment, three types of widths of 2.1 inch, 4.5 inch, and 6.5 inch were implemented as the width of the fine pattern forming sheet 101. For any of these fine pattern forming sheets 101, the width in the width direction of the rotating body 102 was set to 300 mm.

  Even if the bonding of the fine pattern forming sheet 101 and the target object 104 by the rotating body 102 is performed simultaneously with the conveyance of the fine pattern forming sheet 101, the conveyance of the fine pattern forming sheet 101 is stopped. It may be done. In the present embodiment, the bonding was performed with the fine pattern forming sheet 101 stationary.

  When the pressing of the fine pattern forming sheet 101 to the object to be processed 104 is performed simultaneously with the conveyance of the fine pattern forming sheet 101, the rotating body 102 does not hinder the conveyance of the fine pattern forming sheet 101. It is preferable to rotate. For this reason, the rotating means of the rotating body 102 may be configured to passively rotate the rotating body 102 or actively rotate it as the fine pattern forming sheet 101 is conveyed. In particular, it is preferable to passively rotate with the conveyance of the fine pattern forming sheet 101 in order to improve the bonding accuracy. In this case, the rotating means of the rotating body 102 includes a rotating means that passively rotates the rotating body 102, such as a free roller, or the rotational speed of the rotating body 102 so as to synchronize with the conveyance speed of the fine pattern forming sheet 101. A device that passively rotates while controlling can be adopted.

  On the other hand, when the fine pattern forming sheet 101 and the object to be processed 104 are bonded together in a state where the conveyance of the fine pattern forming sheet 101 is stopped, the rotating body 102 rotates around the rotation axis and the object to be processed. In a plane parallel to the main surface 104, it is preferable to move in a direction opposite to the flow direction MD of the fine pattern forming sheet 101 or a direction parallel to the flow direction MD of the fine pattern forming sheet 101.

  In the bonding unit 201 of the thermal nanoimprint apparatus 200 according to the present embodiment, the fine pattern forming sheet 101 and the workpiece 104 are pressed by the rotating body 102 of the pressing unit 100 described above, and the temperature and the pressure are reduced. Thermal nanoimprinting can be performed. Here, when the fine pattern forming sheet 101 is pressed against the workpiece 104, vibration in the direction perpendicular to the in-plane direction of the workpiece 104 is suppressed, and pressure uniformity during pressing is improved. In addition, it is preferable to provide the object holder 205 on the surface opposite to the surface of the object 104 to be in contact with the fine pattern forming sheet 101.

  The holding mechanism of the workpiece holder 205 is not particularly limited as long as it does not contact the workpiece surface of the workpiece 104. The already-described mechanism can be adopted for the workpiece holding unit 205. In addition, as described above, the method for holding the object to be processed 104 preferably holds the object to be processed 104 at a position where the object to be processed 104 and the fine pattern forming sheet 101 do not contact. In the present embodiment, a reduced pressure (suction) chuck is employed.

  Moreover, in the thermal nanoimprint apparatus 200 according to the present embodiment, it is preferable to attach the above-described press heating unit to at least one of the rotating body 102 and the target object holding unit 205. Here, the pressure heating unit is introduced for the purpose of heating the interface between the fine pattern forming sheet 101 and the target object 104 when the fine pattern forming sheet 101 and the target object 104 are pressed by the rotating body 102. . By providing the pressure heating unit, the temperature at the interface between the fine pattern forming sheet 101 and the object to be processed 104 is improved, so that the thermal nanoimprint accuracy is improved. In the present embodiment, both the rotating body 102 and the object-to-be-treated holding unit 205 are provided with a pressure heating unit, and the surface of the rotating body 102 is heated at 90 ° C. to 130 ° C. The surface of was heated in the range of 80 ° C to 150 ° C.

  A release part 206 is provided downstream of the bonding part 201 in the flow direction MD and upstream of the take-up roller 203. In addition, it is preferable that a sufficient interval is provided between the winding roller 203 and the rotating body 102 so that an energy beam irradiation unit and the like which will be described later are provided. The release part 206 is not particularly limited as long as the cover film can be removed from the laminated body 207 composed of the fine pattern forming sheet 101 and the workpiece 104. That is, in the stacked body 207, the object to be processed 104 is fixed, and the vertical movement with respect to the main surface hardly occurs, and the cover film is separated from the object to be processed 104. In particular, if the release part 206 can be released using the flow of the fine pattern forming sheet 101, the twist of the fine pattern forming sheet 101 can be further suppressed and the transfer accuracy can be improved. Furthermore, the pressing of the fine pattern forming sheet 101 and a target object 104 (A) and the separation of the fine pattern forming sheet 101 from another target object 104 (B) can be performed simultaneously. It is possible to improve the tact while suppressing an excessive apparatus. Furthermore, it is preferable to peel the cover film by changing the flow direction of the fine pattern forming sheet 101 in the release part 206, and a peeling roller and a peeling edge as described later can be used.

  Note that the stacked body 207 corresponds to the third stacked body III illustrated in FIGS. 3B and 6A. The target object 104 constituting the laminated body 207 is bonded to the fine pattern forming sheet 101 and integrated.

  The peeling force in the release part 206 is at least perpendicular to the surface to be processed of the object 104 and includes a component in the flow direction MD of the fine pattern forming sheet 101. For example, the exposed surface of the object to be processed 104 of the laminate 207 is held and fixed, and the flow direction MD of the fine pattern forming sheet 101 is changed by the roller or the edge, so that the cover film is peeled off with high transfer accuracy. Can do.

(Energy beam irradiation part)
An energy ray irradiation part can be provided between the bonding part 201 and the release part 206. In the energy ray irradiating unit, the laminated body 207 obtained in the bonding unit 201 is irradiated with energy rays. For this reason, the energy beam irradiation unit may irradiate energy toward the fine pattern forming sheet 101, irradiate energy toward the object 104, or both. In particular, it is preferable to irradiate energy toward at least the object to be processed 104 because the interface strength between the fine pattern forming sheet 101 and the object to be processed 104 can be improved.

(Laminate heating unit)
A laminated body heating unit that heats the laminated body 207 can be provided at a stage before the release part 206 in the flow direction MD of the fine pattern forming sheet 101 and at a stage subsequent to the energy ray irradiation in the flow direction MD. By providing the laminate heating unit, the interface strength between the fine pattern forming sheet 101 and the object to be processed 104 can be improved, so that the thermal nanoimprint accuracy is improved. The heating temperature by the laminate heating unit can be appropriately selected according to the characteristics of the fine pattern forming sheet 101 and is not particularly limited. However, if the temperature is lower than the melting point (Tmc) of the fine pattern forming sheet 101, the apparatus is excessively large. Can be suppressed, and thermal nanoimprint accuracy is improved. In particular, it is preferable that the temperature of the object 104 to be processed can be heated to be in a range of 30 ° C to 200 ° C, and more preferably 60 ° C to 130 ° C. From the viewpoint of conveying the fine pattern forming sheet 101, the heating temperature is generally preferably not more than 0.6 times Tmc. Thus, the laminated body 207 is heated under the heating condition.

(Cooling section)
Furthermore, a cooling unit for cooling the stacked body 207 may be provided before the release part 206 in the flow direction MD of the fine pattern forming sheet 101 and after the stack heating unit. it can. By providing the cooling part, it is possible to improve the peelability when peeling the cover film. Here, in the thermal nanoimprint apparatus 200 according to the present embodiment, the cooling unit is provided apart from the bonding unit 201 with respect to the flow direction MD of the fine pattern forming sheet 101. Furthermore, in this embodiment, since the rotating body 102 as described above is employed, the temperature necessary for thermal nanoimprinting is kept low. For this reason, the excessive increase in the cooling section can be suppressed. The cooling unit only needs to blow air to the stacked body 207. It is preferable that the cooling unit be cooled so that at least the temperature of the object to be processed 104 is 120 ° C. or lower because the peelability can be improved. The optimum temperature after cooling of the workpiece 104 is determined according to the characteristics of the fine pattern forming sheet 101, but is generally preferably 5 ° C. or higher and 60 ° C. or lower, more preferably 18 ° C. or higher and 30 ° C. or lower.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effects of the present invention are exhibited.

  As described above, the present invention has a good film thickness distribution of the first mask layer when the concavo-convex structure formed on the surface of the cover film is transferred to the object to be processed through the first mask layer. In addition, it has the effect of providing a thermal nanoimprinting device that can improve transfer accuracy, efficiently transfer, and does not require excessive equipment. It is useful for the concavo-convex structure processing technology in the manufacture of a base material for light source, a light extraction efficiency and a base material for improving internal quantum efficiency.

1,101 Fine pattern forming sheet 2, 10 Cover film 3 Resin layer 3a, 11, 40 Uneven structure 4, 12 Second mask layer 5, 13 First mask layer 6, 14, 601 Protective film 20, 104 Covered Processing body 21 Intermediate body 22 Fine pattern 102 Rotating body 200 Thermal nanoimprint apparatus 201 Laminating section 206 Molding section 302 Peeling roller 402 Peeling roll 503 Separating section 602a Peeling roller section 606 Suction devices 606a and 606b Suction port

Claims (4)

A cover film having a nanoscale uneven structure formed on one surface; a second mask layer provided inside the recess of the uneven structure; and the cover film covering the uneven structure and the second mask layer. The first mask layer and a protective film covering the surface of the first mask layer are used, and the first mask layer and the second mask layer are formed on the object to be processed. A transfer method for transferring a mask layer,
The transfer method is:
A peeling step of peeling the protective film from the fine pattern forming sheet;
A bonding step of bonding the surface of the first mask layer exposed by peeling the protective film to the surface of the object to be processed after the peeling step;
A transfer method, wherein suction is performed while peeling the protective film with a suction port directed toward a peeling position.   The transfer method according to claim 1, wherein suction is performed with the suction port directed toward both ends of the peeling position. A cover film having a nanoscale uneven structure formed on one surface; a second mask layer provided inside the recess of the uneven structure; and the cover film covering the uneven structure and the second mask layer. The first mask layer and a protective film covering the surface of the first mask layer are used, and the first mask layer and the second mask layer are formed on the object to be processed. A thermal nanoimprint apparatus for transferring a mask layer,
A peeling portion for peeling the protective film from the fine pattern forming sheet;
A bonding portion for bonding the surface of the first mask layer exposed by peeling the protective film toward the surface of the object to be processed;
A thermal nanoimprint apparatus, comprising a suction device having a suction port directed to a peeling position. The thermal nanoimprint apparatus according to claim 3, wherein suction ports of the suction apparatus are directed to both ends of the peeling position.

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