Method for manufacturing laminate, method for manufacturing two-dimensional material laminate, and device for manufacturing laminate including two-dimensional material

Abstract

This method for manufacturing a laminate includes: a preparation step for preparing a laminate (102) in which a first substrate (21), a two-dimensional material (30), and a cured support layer (10) are laminated in the stated order; and a separation step for separating a laminate (103) including the support layer (10) and the two-dimensional material (30) from the first substrate (21).

Description

Manufacturing method of laminate, manufacturing method of two-dimensional material laminate, and manufacturing device of laminate including two-dimensional material

[0001] The present invention relates to a method for manufacturing a laminate, a method for manufacturing a two-dimensional material laminate, and an apparatus for manufacturing a laminate including two-dimensional materials.

[0002] Two-dimensional materials such as two-dimensional carbon materials are expected to have various applications such as wiring materials and transparent electrodes due to their excellent electrical and optical properties. ２ Graphene, a conductive planar crystal composed of bonded carbon atoms, has high optical transmittance and electrical conductivity, and is expected to be used in transparent conductive films, transparent electrodes, transistors, etc. Graphene is typically produced by chemical vapor deposition (CVD) on the surface of a catalytic metal. However, when graphene is used in a device, a process is required to separate and transfer the graphene formed on the catalytic metal.

[0003] Here, Patent Document 1 describes a method for separating graphene formed on a metal substrate over a large area, in which bubbles are formed at the interface between the graphene and the metal substrate, thereby separating a laminate made of graphene and a support layer from the surface of the metal substrate.

[0004] International Publication No. 2013 / 043120

[0005] Patent Literature 1 discloses a method for coating graphene with PMMA (polymethyl methacrylate) as a support layer, and then generating bubbles between the metal substrate and the graphene by an electrochemical method to separate the laminate of the support layer and graphene from the metal substrate. However, this method requires a solvent washing step to remove the PMMA coating layer when the graphene is subsequently transferred to a processing substrate, which poses a problem in productivity.

[0006] Furthermore, as a result of extensive investigations, the present inventors have found a new problem: when the elastic modulus of the support layer is low, the graphene undergoes deformation, such as expansion and contraction, when it is lifted up by the air bubbles, which leads to damage, such as tearing.

[0007] In view of the above, an object of the present disclosure is to provide a method for manufacturing a laminate including a two-dimensional material and a support layer, which can manufacture a laminate that can efficiently transfer the two-dimensional material at a high transfer rate, even if the two-dimensional material has a large area.

[0008] The method for manufacturing a laminate of the present disclosure includes: a preparation step of preparing a laminate in which a first substrate, a two-dimensional material, and a hardened support layer are stacked in this order; and a separation step of separating the laminate including the support layer and the two-dimensional material from the first substrate.

[0009] The method for manufacturing a two-dimensional material laminate of the present disclosure also includes a transfer step of peeling the support layer of the laminate obtained by the above-described method for manufacturing a laminate from the two-dimensional material in contact with a second substrate, thereby transferring the two-dimensional material onto the second substrate, thereby obtaining a two-dimensional material laminate including the second substrate and the two-dimensional material.

[0010] Furthermore, the present disclosure provides an apparatus for manufacturing a laminate including a two-dimensional material, which comprises: a curing unit that cures the support layer attached to the two-dimensional material by supplying a predetermined energy or substance in a laminate in which a first substrate, a two-dimensional material, and a support layer are stacked in this order; and a separation unit that separates the laminate including the support layer and the two-dimensional material from the first substrate.

[0011] According to the method for manufacturing a laminate of the present disclosure, a laminate capable of efficiently transferring a two-dimensional material at a high transfer rate can be manufactured, even if the two-dimensional material has a large area. Furthermore, when the two-dimensional material is transferred to another substrate using the laminate, a two-dimensional material with little surface contamination can be obtained.

[0012] FIG. 1 is a schematic cross-sectional view showing a stack (first stack) having a two-dimensional material on a first substrate. FIG. 2 is a schematic cross-sectional view showing a state (second stack) in which a support layer is attached to the two-dimensional material on the first substrate. FIG. 3 is a schematic cross-sectional view showing a state in which air bubbles are formed between the first substrate and the two-dimensional material. FIG. 4 is a schematic cross-sectional view of a stack (third stack) including a support layer and a two-dimensional material. FIG. 5 is a schematic cross-sectional view showing a state (fourth stack) in which a stack (third stack) including a support layer and a two-dimensional material is placed on a second substrate so that the surface of the stack facing the two-dimensional material contacts the second substrate. FIG. 6 is a schematic cross-sectional view showing a process of peeling the support layer from the fourth stack to obtain a two-dimensional material stack including a second substrate and a two-dimensional material. FIG. 7 is a block diagram showing an example of the configuration of an apparatus for manufacturing a stack including a two-dimensional material.

[0013] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to such embodiments. In the following drawings, components and parts that perform the same function may be described using the same reference numerals, and duplicate descriptions may be omitted or simplified. The embodiments shown in the drawings are schematic to clearly explain the present invention, and do not necessarily accurately represent the size or scale of the actual product. In addition, when the expression "~" is used in this specification, it is used as an expression that includes the numerical values ​​or physical property values ​​before and after it.

[0014] [Method for manufacturing a laminate] A method for manufacturing a laminate according to one embodiment includes: a preparation step of preparing a laminate in which a first substrate, a two-dimensional material, and a hardened support layer are stacked in this order; and a separation step of separating the laminate including the support layer and the two-dimensional material from the first substrate.

[0015] 1 is a schematic cross-sectional view showing a stack 101 having a two-dimensional material 30 on a first substrate 21. The stack 101 may be referred to as a first stack. In the method for manufacturing a stack of this embodiment, as a preliminary step, first, the two-dimensional material 30 is formed on the first substrate 21.

[0016] The first substrate 21 is not particularly limited and may be a metal substrate, ceramic substrate, silicon substrate, resin substrate, etc. Examples of the first substrate 21 include metal substrates made of transition metals such as copper, nickel, cobalt, iron, chromium, gold, platinum, molybdenum, and tungsten; alloy metal substrates of these metals; single crystal substrates such as sapphire, magnesia, spinel, mica, SiC, SiN, and Si, and single crystal substrates whose surfaces have been oxidized; quartz substrates; substrates for forming two-dimensional materials on the surfaces of these substrates, on which thin films of the transition metals listed above are formed, and substrates on which two-dimensional materials are formed on the aforementioned substrates. The first substrate 21 is preferably a substrate for forming two-dimensional materials.

[0017] The method for forming the two-dimensional material on the metal substrate for film formation is not particularly limited, and a CVD method is preferably used. Examples of the film formation method include a thermal CVD method in which a raw material gas is introduced in the presence of a catalytic metal and processed by thermal decomposition of the raw material gas, and a surface wave microwave plasma chemical vapor deposition (CVD) method in which microwave plasma is used for processing. However, any method may be used as long as the two-dimensional material 30 can be formed on the first substrate 21.

[0018] The two-dimensional material 30 is a material having a two-dimensional layered structure made of a single element or two or more elements, and having an extremely thin sheet structure. Graphene, a two-dimensional sheet made only of carbon, is a typical example. The two-dimensional material 30 may also be a ribbon-like film having a width in the nanometer range. Examples of the two-dimensional material 30 include two-dimensional carbon materials, transition metal chalcogenides, molybdenum disulfide, tungsten disulfide, hexagonal boron nitride (h-BN), black phosphorus, and derivatives thereof. Two-dimensional carbon materials, molybdenum disulfide, tungsten disulfide, or hexagonal boron nitride are preferred. Graphene or graphene derivatives are preferred as the two-dimensional carbon material. Graphene is a two-dimensional carbon material consisting of sp ２It is a film formed by bonded carbon atoms, forming a hexagonal lattice structure made of carbon atoms and their bonds. In this specification, multi-layer graphene, in which these films are stacked in 2 to 100 layers, is also referred to as "graphene." Furthermore, the two-dimensional material 30 may be composed of a single layer or multiple layers. When the two-dimensional material is composed of multiple layers, each layer may be composed of the same material or different materials.

[0019] Examples of graphene derivatives include graphene oxide, sulfonated graphene oxide, graphene hydroxide, graphene carbonate, and graphene nitride, and graphene oxide is preferred.

[0020] The laminate 101 may be subjected to a pretreatment process of immersion in water. For example, when the two-dimensional material is graphene and the graphene film-forming catalyst of the laminate 101 is Cu, the laminate 101 is immersed in water at 4 to 100°C for 4 to 72 hours. This treatment causes water to intercalate at the interface between the graphene and Cu, oxidizing the Cu surface. During immersion, the water may be left standing or stirred. Stirring the water makes the Cu surface more likely to oxidize. Other methods include adding a metal salt such as potassium chloride or sodium chloride to water to promote Cu oxidation, or contacting the water with water vapor to oxidize Cu. In either case, water intercalates at the interface between the graphene and Cu, oxidizing the Cu surface. This oxidation weakens the interaction between the graphene and Cu, allowing for effective transfer of the graphene to the support layer 10 in the subsequent process.

[0021] 2 is a schematic cross-sectional view showing a state in which the support layer 10 is attached to the two-dimensional material 30 on the first substrate 21. Here, the stack formed by attaching the support layer 10 to the two-dimensional material 30 on the first substrate 21 is referred to as the stack 102. The stack 102 may also be referred to as the second stack. In the method for manufacturing a stack of this embodiment, the support layer 10 is attached to the two-dimensional material 30 on the first substrate 21.

[0022] By placing the support layer 10 on the two-dimensional material 30 side of the laminate 101 of the first substrate 21 and the two-dimensional material 30, the support layer 10 can be attached to the two-dimensional material 30. This results in a laminate 102. Here, when attaching the support layer 10 to the two-dimensional material 30, the two-dimensional material 30 and the support layer 10 may be pressed together using, for example, a roller or the like.

[0023] After obtaining the laminate 102, autoclave treatment may be performed as necessary. The conditions for the autoclave treatment are not particularly limited, but for example, the temperature is preferably 20 to 300°C, more preferably 30 to 70°C. The pressure is preferably 1.1 to 20 atmospheres, more preferably 2 to 10 atmospheres. The treatment time is preferably 1 to 120 minutes, more preferably 10 to 60 minutes.

[0024] 2 shows an embodiment in which an adhesive tape having a substrate 11 and an adhesive layer 12 is used as the support layer 10. However, this is merely one embodiment, and the support layer 10 may be any layer as long as it is removably removable.

[0025] (Pre-curing step) The method for producing a laminate of this embodiment includes a pre-curing step after the support layer attachment step and before the bubble formation step described below. Here, the pre-curing step is a step of curing an adhesive layer when an adhesive tape having an adhesive layer that hardens upon receiving a predetermined energy or substance is used as the support layer 10. Hereinafter, an adhesive layer that hardens upon receiving a predetermined energy or substance may be referred to as a curable adhesive layer. Furthermore, an adhesive tape having a curable adhesive layer may be referred to as a curable adhesive tape.

[0026] When a curable adhesive tape is used as the support layer 10, the adhesive layer 12 of the support layer 10 (curable adhesive tape) easily conforms to the shape of the two-dimensional material in the support layer attachment process described above. Furthermore, by performing a curing process before the bubble formation process and separation process described below, the support layer 10 (curable adhesive tape) becomes hard enough to suppress deformation of the two-dimensional material 30 when separating a laminate including the support layer 10 and the two-dimensional material 30 from the first substrate 21 in the separation process. Therefore, the two-dimensional material 30 can be separated from the first substrate 21 over a large area and with little or no damage. As a result, a two-dimensional material with a high transfer rate is easily obtained. In one aspect, when the two-dimensional material is graphene, graphene with a high transfer rate and high mobility is easily obtained.

[0027] The curable adhesive layer and the curable adhesive tape will be described in more detail in the description of the "support layer" below.

[0028] (Gas Bubble Formation Process) FIG. 3 is a schematic cross-sectional view showing a state in which a gas bubble B is formed between the first substrate 21 and the two-dimensional material 30. FIG. 3 also shows how the laminate 103 including the support layer 10 and the two-dimensional material 30 is separated from the first substrate 21 due to the formation of the gas bubbles in the gas bubble formation process. In the laminate manufacturing method of this embodiment, a gas bubble B is subsequently formed between the first substrate 21 and the two-dimensional material 30. Here, a gas bubble forming unit 260 is used to form the gas bubble B between the first substrate 21 and the two-dimensional material 30. The gas bubble forming unit 260 includes at least a solution 261, a potential source 262 (e.g., a power source or a battery) having a positive lead 262P and a negative lead 262N, and an anode 263 located in the solution 261 and electrically connected to the positive lead 262P.

[0029] The second laminate 102 is immersed in the solution 261 of the bubble forming unit 260. With the second laminate 102 immersed in the solution 261, the negative lead 262N is electrically connected to the first substrate 21 in the solution 261. Therefore, the first substrate 21 functions as the cathode of the bubble forming unit 260.

[0030] That is, the formation of bubbles B between the first substrate 21 and the two-dimensional material 30 is performed by, for example, an electrochemical reaction in the bubble formation unit 260. As an example, the electrochemical reaction is the release of hydrogen due to electrolysis of water in the solution 261, and bubbles B are formed by the electrochemical reaction.

[0031] More specifically, when a potential is applied to the solution 261, a reduction reaction occurs on the negatively charged first substrate 21 (cathode), hydrogen gas is formed from the first substrate 21, and hydrogen bubbles B are formed on the conductive surface of the first substrate 21. As a result, bubbles B are formed between the first substrate 21 and the two-dimensional material 30. Here, in the bubble forming unit 260, the arrangement of the anode 263 is adjusted so that bubbles B are formed in a concentrated manner between the first substrate 21 and the two-dimensional material 30.

[0032] The solution 261 contains water and at least one electrolyte, preferably 0.01 to 10 moles of electrolyte per liter of water. The electrolyte is not particularly limited and may be a single type or a combination of two or more types. Examples of the electrolyte include sodium hydroxide, potassium hydroxide, sulfuric acid, sodium chloride, and any suitable combination thereof.

[0033] (In-liquid peeling process) In addition, instead of the bubble formation process or the separation process described below, an in-liquid peeling process may be adopted in which the laminate 103 including the support layer 10 and the two-dimensional material 30 is separated from the first substrate 21 in an appropriate liquid such as water.

[0034] In liquid peeling, the laminate 102 is immersed in a bath filled with liquid, and at least one of the support layer 10 and the first substrate 21 is pulled to separate the laminate 103 from the first substrate 21. When separating, the support layer 10 may be peeled or cleaved. The first substrate 21 may be peeled or cleaved.

[0035] Examples of liquids used in submerged peeling include pure water (e.g., water), ion-exchanged water, distilled water, ultrapure water, and alcohols (e.g., ethanol and isopropyl alcohol), either singly or in mixture, as well as aqueous potassium hydroxide solutions and aqueous hydrofluoric acid solutions capable of etching the first substrate. Submerged peeling is primarily used to separate two-dimensional materials synthesized on non-metallic surfaces, such as transition metal chalcogenides, from the non-metallic surfaces. The peel angle when separating the laminate 103 from the first substrate 21 by pulling at least one of the support layer 10 and the first substrate 21 is not particularly limited and is typically 180 degrees or less. However, a small peel angle can prevent defects such as tears and cracks in the two-dimensional material 30 due to changes in the shape of the laminate 103. Therefore, a small peel angle is preferable, preferably 150 degrees or less, and more preferably 120 degrees or less. Furthermore, from the perspective of increasing the size of the peeling device itself, the peel angle is preferably 0 degrees or greater.

[0036] By performing peeling in liquid, the surface energy required to form the new surface that is generated when separating the two-dimensional material from the first substrate can be reduced, allowing for separation with less damage to the two-dimensional material.

[0037] (Separation Process) The method for manufacturing a laminate according to this embodiment includes a process for separating the laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21. FIG. 4 shows a schematic cross-sectional view of the laminate 103 including the support layer 10 and the two-dimensional material 30. The laminate 103 may also be referred to as a third laminate. As shown in FIG. 3, the separation of the laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21 may occur due to the formation of bubbles in the bubble formation process described above. In this case, the bubble formation process and the separation process can be said to be performed simultaneously. Alternatively, the separation of the laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21 may be performed by pulling at least one of the support layer 10 and the first substrate 21 after the bubble formation process described above.

[0038] The laminate 103 separated from the first substrate 21 may be washed with an appropriate cleaning liquid such as ion-exchanged water, pure water such as distilled water, ultrapure water, or alcohol such as ethanol or isopropyl alcohol, if necessary.

[0039] In the manufacturing method of this embodiment, the tensile modulus of the laminate 103 including the support layer 10 and the two-dimensional material 30 is preferably 10 to 3000 MPa. Here, from the viewpoint of ease of handling, the tensile modulus of the laminate 103 is preferably 10 MPa or more, more preferably 40 MPa or more, and even more preferably 70 MPa or more. Furthermore, the tensile modulus of the laminate 103 is preferably 3000 MPa or less, more preferably 2000 MPa or less, even more preferably 1000 MPa or less, and even more preferably 100 MPa or less. When the tensile modulus of the laminate 103 is 3000 MPa or less, when bubbles are formed between the first substrate 21 and the two-dimensional material 30, it is possible to suppress or prevent the bubbles that contribute to separation from escaping from the edge of the laminate 103 before they become large. Furthermore, when the tensile modulus of the laminate 103 is within the above range, it is believed that the laminate 103 is appropriately separated from the first substrate 21 in the separation process, and good low-contamination properties are achieved. The tensile modulus of the laminate 103 is the tensile modulus at 23°C, and may be calculated for the laminate 103 separated from the first substrate 21. The tensile modulus of the laminate 103 separated from the first substrate can be considered to be substantially the same as the tensile modulus of the laminate 103 at the time of bubble formation. Furthermore, since the thickness of the two-dimensional material 30 is usually sufficiently thin compared to the thickness of the support layer 10, it can be said that the two-dimensional material 30 does not substantially affect the modulus of the laminate 103. Therefore, the tensile modulus of the laminate 103 can usually be considered to be substantially the same as the tensile modulus of the support layer 10.

[0040] Specifically, the tensile modulus of a laminate can be calculated as follows. A sample of a laminate (third laminate) of a support and a two-dimensional material, measuring 10 mm wide and 20 mm long, is prepared, chucked at 5 mm above and below the longitudinal direction with a chuck distance of 10 mm, and pulled at a speed of 50 mm / min. The initial tensile modulus is calculated from the slope of the stress-to-strain gradient at the maximum point between 10% strain and 100% strain, and measured using a tensile tester. This is the tensile modulus of the laminate (third laminate). When the tensile modulus has anisotropy that varies depending on the pulling direction, the average of the tensile modulus when pulled in at least two orthogonal directions in the plane is used. For example, the average of the values ​​measured in two orthogonal directions in the plane (MD and TD) is used as the long side direction (length direction).

[0041] Furthermore, when separating the laminate 103 from the first substrate 21 by pulling at least one of the support layer 10 and the first substrate 21 after the bubble formation process, the peel angle is not particularly limited and is typically 180 degrees or less. However, a small peel angle can prevent defects such as tears and cracks from occurring in the two-dimensional material 30 due to changes in the shape of the laminate 103. For this reason, a small peel angle is preferable, preferably 90 degrees or less, and more preferably 60 degrees or less. Furthermore, from the perspective of increasing the size of the peeling device itself, the peel angle is preferably 0 degrees or more. The peel angle refers to the angle between the first substrate 21 and the peeled portion of the laminate 103 when separating the laminate 103 from the first substrate 21.

[0042] The peeling speed when separating the laminate 103 from the first substrate 21 is not particularly limited, but a fast peeling speed shortens the time it takes for the shape of the laminate 103 to change, thereby preventing defects such as tears and cracks from occurring in the two-dimensional material 30. For this reason, the peeling speed is typically 1 mm / min or higher, but a fast peeling speed is preferable, preferably 10 mm / min or higher, and more preferably 100 mm / min or higher. Furthermore, from the viewpoint of stable operation of the device, the peeling speed is preferably 100,000 mm / min or lower, and more preferably 90,000 mm / min or lower. The peeling speed refers to the length of the laminate 103 peeled from the laminate 102 per unit time when separating the laminate 103 from the laminate 102.

[0043] According to the method for manufacturing a laminate of this embodiment, even if the two-dimensional material 30 has a large area, it is possible to manufacture a laminate 103 that can efficiently transfer the two-dimensional material 30 at a high transfer rate. ２ Although the above areas are mentioned, it is readily understood that the laminate manufacturing method of this embodiment is naturally applicable even when the area of ​​the two-dimensional material is relatively small, and includes such cases. Furthermore, in one aspect, since bubbles that release the interaction between the first substrate 21 and the two-dimensional material 30 with a gentle force can be efficiently formed, the two-dimensional material 30 can be separated without tearing or scratching, even if the two-dimensional material 30 has a large area. As a result, a laminate 103 can be manufactured that can efficiently transfer the two-dimensional material 30 at a high transfer rate, even if the two-dimensional material 30 has a large area.

[0044] [Method for manufacturing two-dimensional material laminate] In one embodiment, a method for manufacturing a two-dimensional material laminate includes a transfer step of peeling the support layer of the laminate obtained by the above-described method for manufacturing a laminate from the two-dimensional material in contact with a second substrate, thereby transferring the two-dimensional material onto the second substrate, thereby obtaining a two-dimensional material laminate including the second substrate and the two-dimensional material.

[0045] (Placement Step) In the method for manufacturing a two-dimensional material stack of this embodiment, first, the stack obtained by the above-described method for manufacturing a stack is placed on a second substrate so that the surface of the stack on the two-dimensional material side contacts the second substrate. Figure 5 is a schematic cross-sectional view showing the step (placing step) of placing the stack 103 on the second substrate 40 so that the surface of the stack 103 on the two-dimensional material 30 side contacts the second substrate 40. By the placing step, a stack 104 is obtained in which the second substrate 40 and the stack 103 are stacked.

[0046] Here, when placing the laminate 103 on the second substrate 40, the laminate 103 may be wetted with an appropriate liquid such as water or alcohol, placed on the second substrate (liquid application), and then left to stand or dried, as necessary. This can increase the adhesion of the laminate 103 to the second substrate 40. Furthermore, when placing the laminate 103 on the second substrate 40, the laminate 103 and the second substrate 40 may be pressed together using, for example, a roller or the like. Furthermore, the laminate 103 may be cut to an appropriate size and placed at any desired location on the second substrate 40. This allows the two-dimensional material to be placed at any desired location on the second substrate.

[0047] (Post-curing step) The method for producing a two-dimensional material laminate of this embodiment may include a post-curing step after the placing step and before the transfer step described below. The post-curing step is optional. Here, the post-curing step refers to a step of curing an adhesive layer when an adhesive tape having an adhesive layer that hardens upon receiving a predetermined energy or substance is used as the support layer 10. However, the post-curing step is performed after the bubble-incorporating step in the method for producing a laminate described above, and is distinguished from the pre-curing step that is performed before the bubble-incorporating step.

[0048] Specifically, when a curable adhesive tape is used as the support layer 10, the adhesive layer 12 of the support layer 10 (curable adhesive tape) easily conforms to the shape of the two-dimensional material 30 in the support layer attachment step described above. Furthermore, by performing a post-curing step before the transfer step described below, the adhesive strength of the adhesive layer 12 of the support layer 10 (curable adhesive tape) is reduced, making it easier to peel the support layer 10 (curable adhesive tape) from the two-dimensional material 30 in the transfer step. As a result, a high transfer rate is easily obtained. In one aspect, when the two-dimensional material is graphene, graphene having a high transfer rate and high mobility is easily obtained.

[0049] (Transfer Process) In the method for manufacturing a two-dimensional material laminate of this embodiment, the two-dimensional material is subsequently transferred onto a second substrate by peeling off the support layer, thereby obtaining a two-dimensional material laminate including the second substrate and the two-dimensional material. Figure 6 is a schematic cross-sectional view showing the process of transferring the two-dimensional material 30 onto the second substrate 40 by peeling off the support layer 10. By peeling off the support layer 10 (adhesive sheet) of the laminate 104, the two-dimensional material 30 is transferred onto the second substrate 40, thereby obtaining a laminate 105 including the second substrate 40 and the two-dimensional material 30. This laminate 105 including the second substrate 40 and the two-dimensional material 30 is sometimes referred to as a two-dimensional material laminate.

[0050] The peel angle when peeling the support layer 10 from the laminate 104 is not particularly limited and is usually 180 degrees or less. However, if the peel angle is large, stress is concentrated at the peel tip of the support layer 10, reducing the peel force at the interface between the support layer 10 and the two-dimensional material 30, thereby preventing defects such as tears and cracks from occurring in the two-dimensional material 30. For this reason, the peel angle is preferably large, preferably 90 degrees or more, and more preferably 120 degrees or more. Furthermore, from the viewpoint of the peeling mechanism, the peel angle is preferably 180 degrees or less. The peel angle refers to the angle between the two-dimensional material 30 and the peeled portion of the support layer 10 when peeling the support layer 10 from the laminate 104.

[0051] The peeling speed when peeling the support layer 10 from the laminate 104 is not particularly limited, but if the peeling speed is slow, the elastic properties of the support layer 10 will be reduced, thereby reducing the peel force at the interface between the support layer 10 and the two-dimensional material 30, thereby preventing defects such as tearing and cracking in the two-dimensional material 30. For this reason, the peeling speed is usually 1000 mm / min or less, but a slower peeling speed is preferable, preferably 600 mm / min or less, and more preferably 300 mm / min or less. Furthermore, from the viewpoint of stable operation of the device, the peeling speed is preferably 3 mm / min or more, and more preferably 10 mm / min or more. The peeling speed refers to the length of the support layer 10 peeled from the laminate 104 per unit time when peeling the support layer 10 from the laminate 104.

[0052] The second substrate 40 is a material onto which a two-dimensional material is transferred. The second substrate 40 is preferably a substrate in which the adhesive strength between its transfer surface and the two-dimensional material 30 is stronger than the adhesive strength between the adhesive layer 12 and the two-dimensional material 30 after application of a predetermined energy or substance (e.g., ultraviolet light or heat). Such a second substrate 40 may have a strong interacting force by itself, or may have an interacting force imparted by surface processing. Examples of surface processing include, but are not limited to, applying a curable resin, melting the surface, forming a microstructure, and chemically modifying the surface.

[0053] The second substrate 40 is not particularly limited, and may be any of a metal substrate, a ceramic substrate, a silicon substrate, a resin substrate, etc. The second substrate 40 may be, for example, a SiO ２ / Si substrate, quartz substrate, glass substrate, PET substrate, sapphire substrate, ITO substrate, substrate with two-dimensional material laminated thereon are preferred, SiO ２A / Si substrate is more preferred. Furthermore, the second substrate 40 may be a substrate in which a film made of copper, nickel, iron, or a mixed oxide containing at least one of these is partially formed on the surface of an appropriate base substrate such as a metal substrate, ceramic substrate, silicon substrate, or resin substrate. Here, the area occupied by the film in the area of ​​the surface of the base substrate is preferably 80% or less, and more preferably 70% or less. Furthermore, the area occupied by the film in the area of ​​the surface of the base substrate is preferably 5% or more, and more preferably 15% or more.

[0054] The thickness of the second substrate 40 is not particularly limited and can be selected appropriately, but is preferably 1 μm or more, more preferably 10 μm or more, and even more preferably 100 μm or more, and from the viewpoint of handling, is preferably 100 mm or less, more preferably 20 mm or less, and even more preferably 5 mm or less.

[0055] The two-dimensional material laminate obtained by the method for producing a two-dimensional material laminate according to this embodiment can be applied to transparent conductive films for touch panels and the like, semiconductor devices or electronic devices such as transistors and integrated circuits, transparent electrodes and electrochemical electrodes that require a large area, and the like.

[0056] Two-dimensional material In one embodiment, the two-dimensional material is a 100 mm ２ It is a two-dimensional material with an area of ​​at least 1000 mm.

[0057] The two-dimensional material of this embodiment can be obtained, for example, as a two-dimensional material in a two-dimensional material stack manufactured by the above-mentioned method for manufacturing a two-dimensional material stack.

[0058] The substrate on which the two-dimensional material is laminated can be any of the various substrates exemplified above as the second substrate. When the two-dimensional material is graphene, it is preferable to use a substrate that does not have copper or nickel on the outermost surface.

[0059] In addition, the two-dimensional material of this embodiment is 100 mm ２ The area of ​​the two-dimensional material is preferably 200 mm or more.２ More preferably, it is 7000 mm or more. ２ The upper limit of the area of ​​the two-dimensional material is not particularly limited, but is 200,000 mm ２ The following is practical:

[0060] Furthermore, the transfer rate of the two-dimensional material is preferably 70% or more, more preferably 80% or more, even more preferably 90% or more, and particularly preferably 95% or more. Here, the transfer rate of the two-dimensional material can be calculated as described in the Examples. In the Examples, for a two-dimensional material (graphene) transferred onto a substrate measuring 10 mm long x 20 mm wide, the area ratio of graphene at a total of nine points, including one central point and eight points near the edges (four vertices and four intermediate points between them), is calculated as a percentage, and the average value of the area ratios of graphene at these nine points (nine-point average transfer rate) is used as the transfer rate (%). However, if the size or shape of the substrate is different, the nine measurement points can be determined with reference to the cases described in the Examples.

[0061] The contamination level of the two-dimensional material is preferably -30% or more and 10% or less, more preferably -25% or more and 8% or less, and even more preferably -20% or more and 5% or less. The contamination level can be negative because pre-transfer residue may be removed during the transfer process. If the contamination level of the two-dimensional material is below -30%, the quality of the two-dimensional material before transfer will be reduced due to excessive pre-transfer residue. If the contamination level of the two-dimensional material is above 10%, the performance of the two-dimensional material after transfer will be reduced due to excessive post-transfer residue. The contamination level is calculated as the increase in the amount of carbon element calculated by ESCA analysis of the two-dimensional material stacked on an oxide-film-covered silicon substrate (SUMCO Corporation, silicon (crystal plane (100)), surface thermal oxidation - oxide film thickness 300 nm) relative to the amount of carbon element calculated by the same measurement on the surface of the two-dimensional material on the first substrate before the support layer is attached. The amount of carbon in each sample is determined as the atomic percentage of carbon in the total amount of the five elements, carbon, nitrogen, oxygen, silicon, and copper, by narrow-scan analysis using X-ray photoelectron spectroscopy (ESCA) on the target substrate surface. The analyzer used may be a Quantum 2000 manufactured by ULVAC PHI or an equivalent. More specifically, the amount of contamination can be determined by the method described in the Examples below.

[0062] In addition, when the two-dimensional material is graphene, the mobility of graphene is 2000 cm ２ / V / s or more, and ２ / V / s or more, and 4000 cm ２ The mobility of the two-dimensional material can be calculated by the method described in the examples.

[0063] (Support Layer) The support layer used in the method for producing a laminate of this embodiment is not particularly limited as long as it has curing and removability, and examples thereof include adhesive tape. The adhesive layer contained in the adhesive tape is a viscoelastic body, so it can wet and spread on two-dimensional materials, facilitating large-area pickup. Therefore, adhesive tape is preferred as the support layer. In the method for producing a laminate of this embodiment, since the support layer has removability, it is thought that good low-contamination properties can be obtained. In this specification, removability refers to the property that allows an article attached to an adherend to be easily peeled off from the adherend when peeling it off.

[0064] The adhesive strength A of the support layer to a silicon wafer at 23°C (180° peel strength from the silicon wafer) is preferably 0.001 N / 20 mm to 2.0 N / 20 mm when a 180° peel is performed at a tensile speed of 300 mm / min. From the viewpoint of handleability, the adhesive strength A is preferably 0.001 N / 20 mm or more, more preferably 0.01 N / 20 mm or more, even more preferably 0.03 N / 20 mm or more, and even more preferably 0.05 N / 20 mm or more. From the viewpoint of good removability, the adhesive strength A is preferably 2.0 N / 20 mm or less, more preferably 1.0 N / 20 mm or less, even more preferably 0.5 N / 20 mm or less, and even more preferably 0.1 N / 20 mm or less. Note that the adhesive strength A is measured after the support layer has cured.

[0065] Furthermore, the adhesive strength B at 23°C when peeling the support layer from the two-dimensional material (180° peel force when releasing the two-dimensional material) is preferably 0.001 N / 20 mm to 2.0 N / 20 mm when performing a 180° peel at a pulling speed of 300 mm / min. From the viewpoint of handleability, the adhesive strength B is preferably 0.001 N / 20 mm or more, more preferably 0.01 N / 20 mm or more, even more preferably 0.05 N / 20 mm or more, and even more preferably 0.1 N / 20 mm or more. From the viewpoint of good removability, the adhesive strength B is preferably 2.0 N / 20 mm or less, more preferably 1.5 N / 20 mm or less, even more preferably 0.5 N / 20 mm or less, and even more preferably 0.2 N / 20 mm or less. Note that the adhesive strength B is measured after the support layer has cured.

[0066] The adhesive tape used as the support layer is not particularly limited as long as it has an adhesive layer, and examples thereof include adhesive tapes in a substrate-less form consisting only of an adhesive layer, and adhesive tapes in a substrate-attached form comprising an adhesive layer and a substrate. Among these, from the viewpoint of ease of handling, adhesive tapes in a form comprising an adhesive layer on one side of a substrate (single-sided adhesive tape) are preferred. The concept of adhesive tape here may include those referred to as adhesive sheets, adhesive films, adhesive labels, etc.

[0067] Furthermore, the pressure-sensitive adhesive tape is preferably a curable pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer (curable pressure-sensitive adhesive layer) that cures upon receiving a predetermined energy or substance. Examples of the predetermined energy supplied to cure the pressure-sensitive adhesive layer include active energy rays and heat, with active energy rays being preferred. Examples of active energy rays include ionizing radiation such as α-rays, β-rays, γ-rays, X-rays, neutron beams, and electron beams, as well as ultraviolet rays and visible light. From the viewpoints of versatility in consideration of the scale of the apparatus and reduction of damage to materials, radiation such as electron beams, ultraviolet rays, α-rays, β-rays, γ-rays, and X-rays is preferred, with ultraviolet rays being particularly preferred. That is, the pressure-sensitive adhesive layer is preferably an active energy ray-curable pressure-sensitive adhesive layer that cures upon exposure to active energy rays, preferably a radiation-curable pressure-sensitive adhesive layer that cures upon exposure to radiation, and more preferably an ultraviolet-curable pressure-sensitive adhesive layer that cures upon exposure to ultraviolet rays. The method for generating ultraviolet light is not particularly limited, and any well-known or commonly used generation method can be used, such as a discharge lamp (arc lamp), flash light, laser light, and UV-LED. In the present invention, it is preferable to use a discharge lamp system (arc lamp) or a UV-LED system because of their excellent industrial productivity, and among these, it is preferable to use an irradiation method using a high-pressure mercury lamp, a metal halide lamp, or a UV-LED because of their excellent irradiation efficiency. The wavelength of the ultraviolet light can be any wavelength in the ultraviolet region, but it is preferable to use a wavelength of about 250 to 440 nm, which is used in general photopolymerization and is used in the ultraviolet generation system. Furthermore, examples of substances that can be supplied to cure the pressure-sensitive adhesive layer include a curing agent, moisture, and a reactive compound.

[0068] Examples of polymers contained in the pressure-sensitive adhesive layer include known or commonly used polymers, such as (meth)acrylic polymers, urethane acrylate polymers, urethane polymers, rubber polymers, epoxy polymers, epoxy acrylate polymers, oxetane polymers, silicone polymers, silicone acrylic polymers, polyester polymers, polyether polymers (such as polyvinyl ether), polyamide polymers, fluorine-containing polymers, vinyl acetate / vinyl chloride copolymers, and modified polyolefins. One or more of the above polymers may be used. Among these, (meth)acrylic polymers are preferred. The use of (meth)acrylic polymers facilitates adjustment of the storage modulus and tensile modulus of the pressure-sensitive adhesive layer, and also allows for the production of a pressure-sensitive adhesive composition with an excellent balance between adhesive strength and releasability. Furthermore, contamination of the adherend by components derived from the pressure-sensitive adhesive can be reduced. In this specification, "(meth)acrylic" refers to "acrylic" and / or "methacrylic" (either one or both of "acrylic" and "methacrylic"), and the same applies to other terms.

[0069] When the pressure-sensitive adhesive layer is an active energy ray-curable pressure-sensitive adhesive layer, examples of the pressure-sensitive adhesive layer include a pressure-sensitive adhesive layer containing a polymer having a radiation-polymerizable functional group as a base polymer, and a pressure-sensitive adhesive layer containing a base polymer and a radiation-polymerizable monomer component or oligomer component having a functional group such as a radiation-polymerizable carbon-carbon double bond. Combinations of these may also be used.

[0070] The following description focuses on pressure-sensitive adhesives containing a polymer having a radiation-polymerizable functional group as a base polymer. Examples of the radiation-polymerizable functional group include radiation-radical polymerizable groups (radical-reactive groups), such as groups containing a carbon-carbon unsaturated bond, such as ethylenically unsaturated groups, and radiation-cationically polymerizable groups. Examples of the group containing a carbon-carbon unsaturated bond include vinyl groups, propenyl groups, isopropenyl groups, acryloyl groups, and methacryloyl groups. Examples of the radiation-cationically polymerizable group include epoxy groups, oxetanyl groups, and oxolanyl groups. Among these, groups containing a carbon-carbon unsaturated bond are preferred, with acryloyl groups and methacryloyl groups being more preferred. The radiation-polymerizable functional group may be of one type or two or more types. The radiation-polymerizable functional group may be located in the polymer side chain, in the polymer main chain, or at the end of the polymer main chain.

[0071] An active energy ray-curable pressure-sensitive adhesive composition containing a polymer having a radical-reactive carbon-carbon double bond as a base polymer, which is a preferred embodiment of a pressure-sensitive adhesive composition that forms a pressure-sensitive adhesive layer in a pressure-sensitive adhesive sheet, will be described below.

[0072] In this embodiment, the pressure-sensitive adhesive composition is an active energy ray-curable pressure-sensitive adhesive composition containing a polymer having a radical-reactive carbon-carbon double bond (hereinafter also referred to as a carbon-carbon unsaturated double bond) at a side chain and / or terminal as a base polymer. The base polymer is preferably a polymer having a carbon-carbon unsaturated double bond at least at a side chain.

[0073] Examples of the base polymer include (meth)acrylic polymers, vinyl alkyl ether polymers, silicone polymers, polyester polymers, polyamide polymers, urethane polymers, and styrene-diene block copolymers, and preferably, (meth)acrylic polymers are used.

[0074] The weight-average molecular weight of the base polymer is preferably 300,000 or more, more preferably 400,000 or more, and even more preferably 600,000 to 1,000,000. Within these ranges, bleeding of low molecular weight components can be prevented, and a low-staining PSA composition can be obtained. The molecular weight distribution (weight-average molecular weight / number-average molecular weight) of the base polymer is preferably 1 to 20, and more preferably 3 to 10. By using a base polymer with a narrow molecular weight distribution, bleeding of low molecular weight components can be prevented, and a low-staining PSA composition can be obtained. The weight-average molecular weight and number-average molecular weight can be determined by gel permeation chromatography (solvent: tetrahydrofuran, polystyrene equivalent).

[0075] One aspect of the pressure-sensitive adhesive composition used in the pressure-sensitive adhesive sheet of this embodiment includes a base polymer and a photopolymerization initiator. This base polymer is, for example, a polymer obtained by reacting a monomer composition including a polymer and a monomer having a carbon-carbon unsaturated double bond. In this example, appropriate components are appropriately selected so that the carbon-carbon unsaturated double bond is introduced into the polymer. In this specification, the monomer composition may be a composition containing only a monomer, or may be a composition containing a monomer and any other components such as an oligomer and a polymer.

[0076] The base polymer can be obtained, for example, by reacting a polymer having a hydroxyl group with a monomer composition (hereinafter also referred to as base polymer monomer composition 1) containing a monomer having an isocyanate group and a functional group containing a carbon-carbon unsaturated double bond. By reacting base polymer monomer composition 1, the polymer having a hydroxyl group can be addition polymerized with the monomer having an isocyanate group and a functional group containing a carbon-carbon unsaturated double bond. As a result, a polymer having structural units derived from the monomer having an isocyanate group and a functional group containing a carbon-carbon unsaturated double bond is obtained.

[0077] The polymer having a hydroxyl group can be any suitable polymer having a hydroxyl group introduced therein. Examples include polymers having a hydroxyl group introduced into a (meth)acrylic polymer, a vinyl alkyl ether polymer, a silicone polymer, a polyester polymer, a polyamide polymer, a urethane polymer, a styrene-diene block copolymer, or the like. Preferably, a polymer having a hydroxyl group introduced into a (meth)acrylic polymer is used.

[0078] The (meth)acrylic polymer having a hydroxyl group can be obtained, for example, by polymerizing a monomer composition containing any suitable acrylic or methacrylic acid ester having a linear or branched alkyl group and a monomer having a hydroxyl group. The acrylic or methacrylic acid ester having a linear or branched alkyl group may be used alone or in combination of two or more.

[0079] The linear or branched alkyl group is preferably an alkyl group having 30 or less carbon atoms, more preferably an alkyl group having 1 to 20 carbon atoms, and even more preferably an alkyl group having 4 to 18 carbon atoms. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, an isobutyl group, an amyl group, an isoamyl group, a hexyl group, a heptyl group, a cyclohexyl group, a 2-ethylhexyl group, an octyl group, an isooctyl group, a nonyl group, an isononyl group, a decyl group, an isodecyl group, an undecyl group, a lauryl group, a tridecyl group, a tetradecyl group, a stearyl group, an octadecyl group, and a dodecyl group.

[0080] Any appropriate monomer can be used as the hydroxyl group-containing monomer. Examples include 2-hydroxymethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, and N-(2-hydroxyethyl)acrylamide. Preferably, 2-hydroxymethyl acrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxymethyl methacrylate, and 2-hydroxyethyl methacrylate are used. These monomers may be used alone or in combination of two or more.

[0081] The hydroxyl group-containing monomer preferably accounts for 5 mol% to 40 mol%, more preferably 15 mol% to 30 mol%, and even more preferably 20 mol% to 25 mol%, based on 100 mol% of all monomer components in the monomer composition used in the polymerization of the hydroxyl group-containing polymer. Polymerization of a monomer composition containing a hydroxyl group-containing monomer produces a polymer containing hydroxyl groups. This hydroxyl group can serve as the introduction point for a structural unit derived from a monomer having a functional group containing a carbon-carbon unsaturated double bond and an isocyanate group. For example, a base polymer having a carbon-carbon unsaturated double bond can be obtained by reacting a polymer (prepolymer) containing hydroxyl groups with a monomer having a functional group containing a carbon-carbon unsaturated double bond and an isocyanate group.

[0082] For the purpose of modifying cohesive strength, heat resistance, crosslinkability, etc., other monomer components copolymerizable with the above-mentioned (meth)acrylic acid alkyl ester may be further used as necessary. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid and methacrylic acid; acid anhydride monomers such as maleic anhydride and itaconic anhydride; sulfonic acid group-containing monomers such as styrenesulfonic acid and allylsulfonic acid; (N-substituted) amide monomers such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, and acryloylmorpholine; aminoalkyl (meth)acrylate monomers such as aminoethyl (meth)acrylate; alkoxyalkyl (meth)acrylate monomers such as methoxyethyl (meth)acrylate; maleimide monomers such as N-cyclohexylmaleimide and N-isopropylmaleimide; itaconimide monomers such as N-methylitaconimide and N-ethylitaconimide; succinimide vinyl monomers such as vinyl acetate, vinyl propionate, N-vinylpyrrolidone, and methylvinylpyrrolidone; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy group-containing acrylic monomers such as glycidyl (meth)acrylate; glycol-based acrylic ester monomers such as polyethylene glycol (meth)acrylate and polypropylene glycol (meth)acrylate; acrylic ester monomers having a heterocycle, halogen atom, silicon atom, or the like, such as tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, and silicone (meth)acrylate; olefin-based monomers such as isoprene, butadiene, and isobutylene; and vinyl ether-based monomers such as vinyl ether. These monomer components may be used alone or in combination of two or more.

[0083] The content of the other monomer component copolymerizable with the (meth)acrylic acid alkyl ester in the monomer composition can be any appropriate amount. Specifically, the other monomer component copolymerizable with the (meth)acrylic acid alkyl ester is used so that the total of the (meth)acrylic acid alkyl ester, the hydroxyl group-containing monomer, and any other monomer component copolymerizable with the (meth)acrylic acid alkyl ester is 100 mol %.

[0084] The polymer having a hydroxyl group can be obtained by any suitable method. For example, a (meth)acrylic polymer having a hydroxyl group can be obtained by polymerizing a monomer composition containing a (meth)acrylic acid alkyl ester, a hydroxyl group-containing monomer, and any other monomer component copolymerizable with the (meth)acrylic acid alkyl ester by any suitable polymerization method.

[0085] As described above, the base polymer of the pressure-sensitive adhesive composition is a polymer obtainable, for example, by reacting the above-mentioned hydroxyl-containing polymer with a monomer composition containing a monomer having an isocyanate group and a functional group containing a carbon-carbon unsaturated double bond. The reaction of the hydroxyl group of the hydroxyl-containing polymer with the isocyanate group of the monomer having an isocyanate group and a functional group containing a carbon-carbon unsaturated double bond results in a base polymer having an introduced carbon-carbon unsaturated double bond. The use of this base polymer makes it possible to provide a pressure-sensitive adhesive composition that has excellent irregularity-filling properties and adhesive properties, and that can prevent adhesive residue on the adherend upon peeling.

[0086] Examples of monomers having a functional group containing a carbon-carbon unsaturated double bond and an isocyanate group include monomers having an acryloyl group or a methacryloyl group and an isocyanate group, such as 2-(2-methacryloyloxyethyloxy)ethyl isocyanate, 2-isocyanate ethyl acrylate (2-acryloyloxyethyl isocyanate), 2-isocyanate ethyl methacrylate (2-methacryloyloxyethyl isocyanate), methacryloyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate, and m-isopropenyl-α,α-dimethylbenzyl isocyanate. These may be used alone or in combination of two or more.

[0087] The amount of the monomer having a carbon-carbon unsaturated double bond and an isocyanate group added relative to the number of moles of hydroxyl groups in the hydroxyl group-containing polymer is preferably 10 mol% to 90 mol%, more preferably 30 mol% to 85 mol%, and even more preferably 50 mol% to 80 mol%. When the amount of the monomer having a carbon-carbon unsaturated double bond and an isocyanate group added is within the above range, the pressure-sensitive adhesive composition can be well cured by irradiation with active energy rays, and a pressure-sensitive adhesive composition with excellent releasability can be provided. When the amount of the monomer having a carbon-carbon unsaturated double bond and an isocyanate group added exceeds 90 mol%, the number of reaction sites with the crosslinking agent decreases, and a sufficient crosslinking effect may not be obtained.

[0088] Furthermore, for example, the monomers constituting the (meth)acrylic polymer can be roughly divided into hydrophilic monomers, hydrophobic monomers, and monomers other than the hydrophilic and hydrophobic monomers.

[0089] As the hydrophilic monomer, any appropriate monomer having a polar group can be used. Specifically, carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; acid anhydride monomers such as maleic anhydride and itanoic anhydride; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, and 1-hydroxypropyl (meth)acrylate; Hydroxyl group-containing monomers such as 0-hydroxydecyl, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl methacrylate; sulfonic acid group-containing monomers such as styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid; phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate; (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N-butyl (meth)acrylamide, N-methylol (meth)acrylamide, N-methylolpropane (meth)acrylamide, and acryloylmorpholine; (meth)acrylic acid aminoalkyl monomers such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and t-butylaminoethyl (meth)acrylate; and (meth)methoxy acrylate. alkoxyalkyl (meth)acrylate monomers such as ethyl, and ethoxyethyl (meth)acrylate; maleimide monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, and N-phenylmaleimide; itaconimide monomers such as N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, and N-laurylitaconimide;succinimide-based monomers such as N-(meth)acryloyloxymethylene succinimide, N-(meth)acryloyl-6-oxyhexamethylene succinimide, and N-(meth)acryloyl-8-oxyoctamethylene succinimide; vinyl-based monomers such as vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholine, N-vinylcarboxylic acid amides, styrene, α-methylstyrene, and N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy group-containing acrylic monomers such as glycidyl (meth)acrylate; polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, and the like. p) Glycol-based acrylic ester monomers such as methoxyethylene glycol acrylate and methoxypolypropylene glycol (meth)acrylate; acrylic ester-based monomers having heterocycles, halogen atoms, silicon atoms, etc., such as tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, and silicon (meth)acrylate; and polyfunctional monomers such as hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy acrylate, polyester acrylate, and urethane acrylate. Hydrophilic monomers that can be used include hydroxyl group-containing monomers and / or (N-substituted) amide-based monomers. Only one hydrophilic monomer may be used, or two or more may be used in combination. ;

[0090] The hydrophobic monomer may be any suitable monomer as long as it has hydrophobicity. Specific examples include vinyl alkyl or aryl ethers having an alkyl group having 9 to 30 carbon atoms, such as vinyl 2-ethylhexanoate, vinyl laurate, vinyl stearate, and stearyl vinyl ether; hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl acrylate, isononyl acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, lauryl (meth)acrylate, oleyl (meth)acrylate, palmityl (meth)acrylate, and stearyl (meth)acrylate; unsaturated vinyl esters of (meth)acrylic acid derived from fatty acids and aliphatic alcohols; monomers derived from cholesterol; and olefin monomers such as 1-butene, 2-butene, 1-pentene, 1-hexene, 1-octene, isobutylene, and isoprene. The hydrophobic monomer may be used alone or in combination of two or more. The hydrophobic monomer used in the present invention refers to a monomer having a solubility of 0.02 g or less in 100 g of water.

[0091] The base polymer may further contain a monomer component other than the hydrophilic monomer and the hydrophobic monomer. Examples of the other monomer component include alkyl acrylates such as butyl acrylate and ethyl acrylate. The other monomer components may be used alone or in combination of two or more.

[0092] When a hydroxyl group-containing polymer is used, the ratio of the hydrophilic monomer other than the hydroxyl group-containing monomer to the total amount of monomer components other than the hydroxyl group-containing monomer (100 mol%) is preferably 0 to 50 mol%, more preferably 0 to 45 mol%, and even more preferably 0 to 40 mol%. Furthermore, by setting the ratio of the hydrophilic monomer other than the hydroxyl group-containing monomer to 50 mol% or less to the total amount of monomer components other than the hydroxyl group-containing monomer (100 mol%), the polarity of the adhesive is not too high, thereby maintaining water resistance and moisture resistance, and the cohesive strength is not too high, thereby maintaining adhesive strength. The lower the ratio, the better; however, the ratio may be, for example, 5 mol% or more, 15 mol% or more, or 25 mol% or more.

[0093] The above description has focused on the case where a base polymer is obtained by reacting a monomer composition (base polymer monomer composition 1) containing a polymer having a hydroxyl group with a monomer having a carbon-carbon unsaturated double bond and an isocyanate group. However, the base polymer is not limited to this. That is, the base polymer can be prepared, for example, by reacting a polymer having a reactive functional group (first functional group) with a compound having a functional group (second functional group) capable of reacting with the first functional group to form a bond and a functional group containing a carbon-carbon unsaturated double bond, while maintaining the radiation polymerizability of the carbon-carbon unsaturated double bond. For this reason, the base polymer preferably contains a structural portion derived from the polymer having the first functional group and a structural portion derived from the compound having the second functional group and a carbon-carbon unsaturated double bond. In addition to acryloyl and methacryloyl groups, examples of functional groups containing a carbon-carbon unsaturated bond include vinyl, propenyl, and isopropenyl groups.

[0094] Examples of combinations of the first functional group and the second functional group include a carboxy group and an epoxy group, an epoxy group and a carboxy group, a carboxy group and an aziridyl group, an aziridyl group and a carboxy group, a hydroxy group and an isocyanate group, and an isocyanate group and a hydroxy group. Among these, from the viewpoint of ease of reaction tracking, a combination of a hydroxy group and an isocyanate group, and a combination of an isocyanate group and a hydroxy group are preferred. The above combinations may be one type only, or two or more types.

[0095] The base polymer can be prepared, for example, by polymerizing (copolymerizing) raw material monomers containing a monomer component having a first functional group to obtain a polymer having the first functional group, and then subjecting a compound having the second functional group and a carbon-carbon unsaturated double bond to a condensation reaction or addition reaction with the polymer while maintaining the radiation polymerizability of the carbon-carbon unsaturated double bond.

[0096] Various common solvents may be used during polymerization of the monomer components. Examples of such solvents include organic solvents such as esters such as ethyl acetate and n-butyl acetate; aromatic hydrocarbons such as toluene and benzene; aliphatic hydrocarbons such as n-hexane and n-heptane; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; and ketones such as methyl ethyl ketone and methyl isobutyl ketone. One or more of the above solvents may be used.

[0097] The polymerization initiator, chain transfer agent, emulsifier, etc. used in the radical polymerization of the monomer components are not particularly limited and can be appropriately selected and used. The weight-average molecular weight of the polymer can be controlled by the amounts of the polymerization initiator and chain transfer agent used and the reaction conditions, and the amounts used are adjusted appropriately depending on the types of these.

[0098] As the polymerization initiator used for polymerizing the monomer components, a thermal polymerization initiator, a photopolymerization initiator (photoinitiator), etc. can be used depending on the type of polymerization reaction. Only one type of the polymerization initiator may be used, or two or more types may be used.

[0099] The thermal polymerization initiator is not particularly limited, and examples thereof include azo-based polymerization initiators, peroxide-based polymerization initiators, redox-based polymerization initiators, etc. The amount of the thermal polymerization initiator used is preferably 1 part by mass or less, more preferably 0.005 to 1 part by mass, and even more preferably 0.02 to 0.5 parts by mass, relative to 100 parts by mass of the total amount of all monomer components constituting the polymer having the first functional group.

[0100] As the photopolymerization initiator used for polymerizing the monomer components, any of the photopolymerization initiators exemplified below as the photopolymerization initiator contained in the pressure-sensitive adhesive composition can be used as appropriate.

[0101] The reaction between the polymer having the first functional group and the compound having the second functional group and the radiation-polymerizable functional group can be carried out, for example, by stirring in a solvent in the presence of a catalyst. Examples of the solvent include those described above. The catalyst is appropriately selected depending on the combination of the first functional group and the second functional group. The reaction temperature in the reaction is, for example, 5 to 100°C, and the reaction time is, for example, 1 to 36 hours.

[0102] The pressure-sensitive adhesive composition of this embodiment contains a photopolymerization initiator or a thermal polymerization initiator in addition to the base polymer. Any appropriate initiator can be used as the photopolymerization initiator that can be contained in the pressure-sensitive adhesive composition. Examples of the photopolymerization initiator include acylphosphine oxide photoinitiators such as ethyl 2,4,6-trimethylbenzylphenylphosphinate and (2,4,6-trimethylbenzoyl)phenylphosphine oxide; α-ketol compounds such as 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, and 1-hydroxycyclohexylphenyl ketone; acetophenone compounds such as methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, and 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether; and benzyl dimethyl ketal. aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime; benzophenone compounds such as benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone; thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketones; acylphosphonates; and α-hydroxyacetophenones such as 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropane-1. Preferably, 2,2-dimethoxy-2-phenylacetophenone and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropane-1 can be used.The photopolymerization initiator may be used alone or in combination of two or more. The thermal polymerization initiator that can be contained in the pressure-sensitive adhesive composition is not particularly limited, but examples thereof include an azo-based polymerization initiator, a peroxide-based polymerization initiator, and a redox-based polymerization initiator.

[0103] As the photopolymerization initiator, commercially available products may be used, such as Omnirad 127D and Omnirad 651, both manufactured by IGM Resins. As the thermal polymerization initiator, commercially available products may be used, such as Niper (registered trademark) BW, both manufactured by NOF Corporation.

[0104] The photopolymerization initiator or thermal polymerization initiator can be used in any appropriate amount. The content of the photopolymerization initiator or thermal polymerization initiator is preferably 0.5 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, relative to 100 parts by mass of the base polymer. If the content of the photopolymerization initiator or thermal polymerization initiator is less than 0.5 parts by mass, there is a risk that the composition will not cure sufficiently upon irradiation with active energy rays or heat treatment. If the content of the photopolymerization initiator or thermal polymerization initiator exceeds 20 parts by mass, there is a risk that the storage stability of the pressure-sensitive adhesive composition will decrease.

[0105] The PSA composition may further contain any appropriate additives, such as a crosslinking agent, a catalyst (e.g., a platinum catalyst), a tackifier, a plasticizer, a pigment, a dye, a filler, an antioxidant, a conductive material, an ultraviolet absorber, a light stabilizer, a release modifier, a softener, a surfactant, a flame retardant, and a solvent.

[0106] The pressure-sensitive adhesive composition preferably further contains a crosslinking agent. Examples of crosslinking agents include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, aziridine-based crosslinking agents, and chelate-based crosslinking agents. The content of the crosslinking agent can be adjusted to any appropriate amount, but is preferably 0.5 to 20 parts by mass, more preferably 4 to 15 parts by mass, and even more preferably 6 to 12 parts by mass, relative to 100 parts by mass of the base polymer. The flexibility of the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition can be controlled by the content of the crosslinking agent. A content of 0.5 parts by mass or more is preferable because it provides an appropriate cohesive strength. A content of 20 parts by mass or less is preferable because it provides an appropriate adhesive strength.

[0107] As the crosslinking agent, an isocyanate-based crosslinking agent is preferably used. Isocyanate-based crosslinking agents are preferred because they can react with various functional groups. Particularly preferably, a crosslinking agent having three or more isocyanate groups is used. By using an isocyanate-based crosslinking agent as the crosslinking agent and setting the content of the crosslinking agent within the above range, it is possible to form a pressure-sensitive adhesive layer that has excellent releasability and significantly less adhesive residue even after heating.

[0108] Next, a description will be given of a case where a pressure-sensitive adhesive containing a base polymer and a radiation-polymerizable monomer or oligomer having a functional group such as a radiation-polymerizable carbon-carbon double bond is used. When a pressure-sensitive adhesive containing a radiation-polymerizable monomer or oligomer is used, any appropriate monomer or oligomer can be used as the radiation-polymerizable monomer or oligomer. Examples of radiation-polymerizable monomers include urethane (meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and 1,4-butanediol di(meth)acrylate. Examples of radiation-polymerizable oligomers include urethane-based oligomers, polyether-based oligomers, polyester-based oligomers, polycarbonate-based oligomers, and polybutadiene-based oligomers. The oligomer preferably has a molecular weight of about 100 to 30000. The monomer and oligomer may be used alone or in combination of two or more.

[0109] The monomer and / or oligomer may be used in any appropriate amount depending on the type of PSA used. For example, the amount is preferably 5 to 500 parts by weight, more preferably 40 to 150 parts by weight, per 100 parts by weight of the base polymer constituting the PSA.

[0110] As the base polymer contained in the PSA containing the radiation-polymerizable monomer or oligomer, an appropriate resin such as the acrylic polymer described above is used depending on the type of PSA. The PSA containing the radiation-polymerizable monomer or oligomer may also contain a polymerization initiator, a crosslinking agent, etc. as appropriate, which are the same as the components described for the PSA containing the polymer having a radiation-polymerizable functional group as the base polymer.

[0111] The pressure-sensitive adhesive layer may also contain a thermoplastic resin. Examples of thermoplastic resins include natural or synthetic rubbers such as natural rubber, polyisobutylene, polyisoprene, chloroprene rubber, butyl rubber, and nitrile butyl rubber; olefin elastomers such as ethylene-propylene copolymer, ethylene-propylene-diene copolymer, ethylene-vinyl acetate copolymer, polybutene, and chlorinated polyethylene; styrene elastomers such as styrene-butadiene-styrene copolymer, styrene-isoprene-styrene copolymer, and hydrogenated products thereof; polyester elastomers; polyamide elastomers; and various thermoplastic elastomers such as polyurethane elastomers. These rubber components or thermoplastic elastomer components may be used alone or in combination of two or more.

[0112] The pressure-sensitive adhesive layer can be produced, for example, by applying a pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer onto a release liner and drying and curing the resulting pressure-sensitive adhesive composition layer, or by applying the pressure-sensitive adhesive composition onto a release liner, which may be further heated and dried, if necessary.

[0113] The thickness of the pressure-sensitive adhesive layer is not particularly limited, but from the viewpoint of exhibiting good adhesion to two-dimensional materials, it is preferably 2 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more, and from the viewpoint of forming a smooth pressure-sensitive adhesive layer, it is preferably 500 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less.

[0114] Furthermore, in the above-described separation step, when a laminate including a pressure-sensitive adhesive tape as a support layer and a two-dimensional material is separated from a first substrate, the tensile modulus of the pressure-sensitive adhesive layer in the pressure-sensitive adhesive tape in the laminate is preferably 1 MPa to 1000 MPa. Here, from the viewpoint of suppressing damage to the two-dimensional material due to deformation, the tensile modulus of the pressure-sensitive adhesive layer is preferably 1 MPa or more, more preferably 5 MPa or more, more preferably 9 MPa or more, more preferably 10 MPa or more, more preferably 20 MPa or more, and even more preferably 100 MPa or more. Furthermore, the tensile modulus of the pressure-sensitive adhesive layer is preferably 1000 MPa or less, more preferably 200 MPa or less, and even more preferably 150 MPa or less. When the tensile modulus of the pressure-sensitive adhesive layer close to the first substrate during bubble formation is 1000 MPa or less, it is easier to suppress or prevent bubbles contributing to separation from escaping from the edge of the laminate before they grow large when bubbles are formed between the first substrate and the two-dimensional material. The tensile modulus of the pressure-sensitive adhesive layer is the tensile modulus at 23°C.

[0115] Specifically, the tensile modulus of the pressure-sensitive adhesive layer can be calculated as follows: A cylindrical sample of the pressure-sensitive adhesive layer is rolled to a length of 30 mm and a diameter of 1 mm, and the sample is chucked at 10 mm above and below in the longitudinal direction and pulled at a rate of 50 mm / min. The initial tensile modulus is calculated from the slope of the stress versus strain gradient at the maximum point between 10% strain and 100% strain, and measured using a tensile tester; this is the tensile modulus of the pressure-sensitive adhesive layer.

[0116] Furthermore, the tensile modulus of elasticity of the adhesive layer in the adhesive tape in the laminate separated from the first substrate can be considered to be substantially the same as the tensile modulus of elasticity of the adhesive layer in the adhesive tape in the laminate at the time of bubble formation.

[0117] Furthermore, when the pressure-sensitive adhesive layer is a curable pressure-sensitive adhesive layer, the tensile modulus of the pressure-sensitive adhesive layer after curing is preferably within the above-mentioned range.

[0118] Specifically, the tensile modulus of the pressure-sensitive adhesive layer after curing can be calculated as follows: ２A cylindrical sample is irradiated with ultraviolet light and rolled to a length of 30 mm and a diameter of 1 mm, and chucked at 10 mm above and below the length, and pulled at a rate of 50 mm / min. The initial tensile modulus is calculated from the slope of the stress versus strain gradient at a maximum point between 10% strain and 100% strain, and measured using a tensile tester. This is the tensile modulus of the pressure-sensitive adhesive layer after curing. If the pressure-sensitive adhesive layer after ultraviolet irradiation is brittle and easily breaks when rolled to a length of 30 mm and a diameter of 1 mm, it can be wound without breakage by masking 5% or less of the winding direction at the start of winding to prevent ultraviolet irradiation.

[0119] Examples of substrates constituting the pressure-sensitive adhesive tape include those made of resin, nonwoven fabric, woven fabric, metal foil, paper, etc. Among these, substrates made of resin (resin substrates) are preferred from the viewpoints of smoothness, ease of handling, and cost.

[0120] Specific examples of resins constituting the substrate include polyester-based resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polybutylene naphthalate (PBN), polyolefin-based resins such as ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer, polyethylene, polypropylene, and ethylene-propylene copolymer, polyurethane-based resins, polyvinyl alcohol, polyvinylidene chloride, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyamide, polyimide, celluloses, fluorine-based resins, polyethers, polystyrene-based resins such as polystyrene, polycarbonate, and polyethersulfone. Among these, from the viewpoint of tensile modulus that provides flexibility, ethylene-vinyl acetate copolymer (EVA), polyolefin-based resins, and polyurethane-based resins are preferred, and ethylene-vinyl acetate copolymer (EVA) is particularly preferred.

[0121] The thickness of the substrate can be set to any appropriate value. The thickness of the substrate is preferably 10 μm to 300 μm, more preferably 50 μm to 150 μm. The substrate may be an unstretched film, or may be one that has been subjected to uniaxial or biaxial stretching treatment as necessary. Furthermore, when the pressure-sensitive adhesive layer 12 is an active energy ray-curable pressure-sensitive adhesive layer, the substrate 11 preferably has a property of transmitting active energy rays such as ultraviolet rays.

[0122] The tensile modulus of the substrate is preferably 10 MPa to 4000 MPa. Here, from the viewpoint of ease of handling of the pressure-sensitive adhesive tape, the tensile modulus of the substrate is preferably 10 MPa or more, more preferably 30 MPa or more, and even more preferably 50 MPa or more. Furthermore, the tensile modulus of the substrate is preferably 4000 MPa or less, more preferably 1000 MPa or less, and even more preferably 100 MPa or less. By adjusting the tensile modulus of the relatively hard substrate, among the components constituting the pressure-sensitive adhesive tape, to 4000 MPa or less, it is easy to adjust the tensile modulus of the pressure-sensitive adhesive tape as a support layer to 3000 MPa or less. As a result, when bubbles are formed between the first substrate and the two-dimensional material, it is easy to suppress or prevent the bubbles that contribute to separation from escaping from the edge of the laminate including the pressure-sensitive adhesive tape and the two-dimensional material before they grow large. The tensile modulus of the substrate is the tensile modulus at 23°C.

[0123] The tensile modulus of the substrate can be calculated specifically as follows. A sample of the substrate with a width of 10 mm and a length of 20 mm is prepared, chucked at 5 mm above and below the longitudinal direction with a chuck distance of 10 mm, and pulled at a speed of 50 mm / min. The initial tensile modulus is calculated from the slope at the point where the slope of the stress versus strain is maximum between 10% strain and 100% strain, and measured using a tensile tester. This is the tensile modulus of the substrate. When the tensile modulus has anisotropy that varies depending on the pulling direction, the average of the tensile modulus when pulled in at least two orthogonal directions in the plane is used. For example, the average of the values ​​measured in two orthogonal directions in the plane (MD and TD) is used as the long side direction (length direction).

[0124] (Method for producing pressure-sensitive adhesive tape) The pressure-sensitive adhesive tape can be produced by any appropriate method. In one embodiment, the pressure-sensitive adhesive tape can be produced by forming a pressure-sensitive adhesive layer on a substrate. The pressure-sensitive adhesive layer may be formed by coating the substrate with the composition that forms the pressure-sensitive adhesive layer, or the pressure-sensitive adhesive layer may be formed on any appropriate release liner and then transferred to the substrate. As the coating method, various methods can be used, such as bar coater coating, air knife coating, gravure coating, gravure reverse coating, reverse roll coating, lip coating, die coating, dip coating, offset printing, flexographic printing, and screen printing.

[0125] [Apparatus for manufacturing laminated body including two-dimensional material] According to one embodiment, an apparatus for manufacturing a laminated body including a two-dimensional material includes: a curing unit that cures the support layer attached to the two-dimensional material by supplying a predetermined energy or substance in a laminate in which a first substrate, a two-dimensional material, and a support layer are stacked in this order; and a separating unit that separates the laminated body including the support layer and the two-dimensional material from the first substrate.

[0126] FIG. 7 is a block diagram showing an example of the configuration of an apparatus for manufacturing a laminate including a two-dimensional material. The apparatus 200 for manufacturing a laminate including a two-dimensional material according to this embodiment is configured to include at least a pre-curing unit 240 (corresponding to the "curing unit" of the present invention) and a separation unit. The apparatus 200 for manufacturing a laminate including a two-dimensional material according to this embodiment is also configured to include a preliminary preparation unit 210, a support layer attachment unit 220, a first conveyance unit 230, a second conveyance unit 250, a bubble formation unit 260, a third conveyance unit 280, a placement unit 290, and a transfer unit 310. The apparatus 200 for manufacturing a laminate including a two-dimensional material according to this embodiment may also be configured to include a mechanical separation unit 270 and a post-curing unit 300. The separation unit is configured to include at least the bubble formation unit 260, and may further include the mechanical separation unit 270.

[0127] The preliminary preparation unit 210 performs the preliminary step. The support layer attachment unit 220 performs the support layer attachment step. The first transport unit 230 transports the second laminate 102 from the support layer attachment unit 220 to the pre-curing unit 240. The first transport unit 230 is not particularly limited, but examples thereof include a conveyor, a robot arm, and a suction arm. The pre-curing unit 240 performs the pre-curing step. The second transport unit 250 transports the second laminate 102 from the pre-curing unit 240 to the bubble formation unit 260. The second transport unit 250 is not particularly limited, but examples thereof include a conveyor, a robot arm, and a suction arm. The bubble formation unit 260 performs the bubble formation step and the separation step. The third transport unit 280 transports the third laminate 103 from the bubble formation unit 260 (or the mechanical separation unit 270 in some cases) to the placement unit 290. The third transport unit 280 is not particularly limited, but examples thereof include a conveyor, a robot arm, a suction arm, etc. The placement unit 290 performs the placement step. The transfer unit 310 performs the transfer step.

[0128] When the manufacturing apparatus 200 for a laminate including a two-dimensional material includes the mechanical separation unit 270, the mechanical separation unit 270 performs the separation process. The mechanical separation unit 270 may be configured integrally with or separately from the bubble formation unit 260. When the mechanical separation unit 270 is configured separately from the bubble formation unit 260, the third conveying unit 280 conveys the third laminate 103 from the mechanical separation unit 270 to the placing unit 290.

[0129] When the manufacturing apparatus 200 for a laminate including a two-dimensional material includes the post-curing unit 300, the post-curing unit 300 performs the post-curing step.

[0130] The manufacturing apparatus 200 for a laminate including a two-dimensional material may include a support layer feeding unit that feeds the support layer 10 to the support layer adhering unit 220, or the support layer 10 may be fed to the support layer adhering unit 220 from the preliminary preparation unit 210. The manufacturing apparatus 200 may further include a substrate recovery unit that recovers the first substrate 21 after the separation step, or a support layer recovery unit that recovers the support layer 10 after the transfer step.

[0131] In addition, the manufacturing apparatus 200 for a laminate including a two-dimensional material may be provided with a submerged peeling unit that performs a submerged peeling process as a separation unit, instead of the bubble forming unit 260 (or in some cases the mechanical separation unit 270).

[0132] As described above, the present specification describes the following: (1) A method for manufacturing a laminate, comprising: a preparation step of preparing a laminate 102 in which a first substrate 21, a two-dimensional material 30, and a hardened support layer 10 are stacked in this order; and a separation step of separating a laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21. (2) A method for manufacturing a laminate according to (1), wherein the preparation step comprises a preliminary step of forming the two-dimensional material 30 on the first substrate 21. (3) A method for manufacturing a laminate according to (1) or (2), wherein the preparation step comprises a support layer attachment step of attaching the support layer 10, which hardens when supplied with a predetermined energy or substance, to the two-dimensional material 20 on the first substrate 21. (4) The method for manufacturing a laminate according to any one of (1) to (3), wherein the preparation step includes a curing step of curing the support layer 10 attached to the two-dimensional material 30 by supplying a predetermined energy or substance. (5) The method for manufacturing a laminate according to (4), wherein the curing step includes supplying active energy rays as the predetermined energy. (6) The method for manufacturing a laminate according to any one of (1) to (5), wherein the separation step includes a bubble formation step of forming bubbles B between the first substrate 21 and the two-dimensional material 30 before the separation step. (7) The method for manufacturing a laminate according to (6), wherein the separation step separates the laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21 by forming the bubbles B or by pulling at least one of the support layer 10 and the first substrate 21 after forming the bubbles B.(8) The method for manufacturing a laminate according to any one of (1) to (5), wherein the separation step includes a liquid peeling step of immersing the laminate 102, in which the first substrate 21, the two-dimensional material 30, and the cured support layer 10 are stacked in this order, in a liquid, and pulling at least one of the support layer 10 and the first substrate 21 in the liquid, thereby peeling off the laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21. (9) The method for manufacturing a laminate according to any one of (1) to (8), wherein the support layer 10 is an adhesive tape including an adhesive layer 12 and a base material 11. (10) A method for manufacturing a two-dimensional material stack, comprising a transfer step of transferring the two-dimensional material 30 onto the second substrate 40 by peeling the support layer 10 of the stack 103 obtained by the method for manufacturing a stack according to any one of (1) to (9) from the two-dimensional material 30 in contact with the second substrate 40, thereby obtaining a two-dimensional material stack 105 including the second substrate 40 and the two-dimensional material 30. (11) A method for manufacturing a two-dimensional material stack according to (10), comprising a placing step of placing the stack 103 on the second substrate 40 so that the surface on the two-dimensional material 30 side is in contact with the second substrate 40. (12) A manufacturing apparatus 200 for a laminate including a two-dimensional material, comprising: a curing unit (e.g., 240) that cures the support layer 10 attached to the two-dimensional material 30 by supplying a predetermined energy or substance in a laminate 102 in which a first substrate 21, a two-dimensional material 30, and a support layer 10 are laminated in this order; and a separation unit (e.g., 260, 270) that separates a laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21. (13) The manufacturing apparatus 200 for a laminate including a two-dimensional material according to (12), further comprising a preparatory unit (e.g., 210) that forms the two-dimensional material 30 on the first substrate 21.(14) The manufacturing apparatus 200 for a laminate including a two-dimensional material according to (12) or (13), further comprising a support layer attachment unit (e.g., 220) that attaches the support layer 10, which hardens when supplied with the predetermined energy or the substance, to the two-dimensional material 30 on the first substrate 21. The manufacturing apparatus 200 for a laminate including a two-dimensional material. (15) The manufacturing apparatus 200 for a laminate including a two-dimensional material according to any one of (12) to (14), wherein the separation unit is composed of a bubble forming unit (e.g., 260) that forms bubbles B at least between the first substrate 21 and the two-dimensional material 30, and separates the laminate 103 including the support layer 10 and the two-dimensional material 30 from the first substrate 21 by forming the bubbles B or by pulling at least one of the support layer 10 and the first substrate 21 after forming the bubbles B. (16) The manufacturing apparatus 200 for a laminate including a two-dimensional material according to (15), further comprising a placing unit (e.g., 290) that places the laminate 103, which includes the support layer 10 and the two-dimensional material 30 and has been separated from the first substrate 21 by the separating unit, on the second substrate 40 so that the surface of the laminate 103 facing the two-dimensional material 30 contacts the second substrate 40. (17) The manufacturing apparatus 200 for a laminate including a two-dimensional material according to any one of (12) to (16), further comprising a transfer unit (e.g., 310) that transfers the two-dimensional material 30 onto the second substrate 40 by peeling the support layer 10 of the laminate 103 including the support layer 10 and the two-dimensional material 30, which has been separated from the first substrate 21 by the separation unit, from the two-dimensional material 30 in contact with the second substrate 40, thereby obtaining a two-dimensional material laminate 105 including the second substrate 40 and the two-dimensional material 30.

[0133] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples in any way.

[0134] <Adhesive Sheet 1> A monomer composition (solids concentration: 40%) was prepared by mixing three types of monomers: 71.2 g of 2-ethylhexyl acrylate (2EHA) (60 mol % of the total amount of monomers not containing a hydroxyl group), 36.4 g of acryloylmorpholine (ACMO) (40 mol % of the total amount of monomers not containing a hydroxyl group), and 20.4 g of 4-hydroxybutyl acrylate (4HBA) (amount equivalent to 22 mol % when the total amount of monomers not containing a hydroxyl group was taken as 100 mol %), 0.3 mass % of a polymerization initiator (manufactured by NOF Corporation, trade name: Nyper (registered trademark) BW) relative to the total mass of the monomers, and a solvent (ethyl acetate). The monomer composition was placed in a 1 L round-bottom separable flask equipped with a separable cover, a separatory funnel, a thermometer, a nitrogen inlet tube, a Liebig condenser, a vacuum seal, a stirring rod, and a stirring blade. The mixture was then purged with nitrogen at room temperature for 2 hours while stirring. The mixture was then polymerized at 61°C for 8 hours under a nitrogen inflow to obtain a resin solution. To the resulting resin solution was added 12.0 g (equivalent to 12 mol% when the total amount of hydroxyl-free monomers was taken as 100 mol%) of a compound (manufactured by Showa Denko K.K., trade name "Karenz MOI") that introduces a carbon-carbon unsaturated double bond. Furthermore, 0.063 parts by mass of dibutyltin IV dilaurate (manufactured by Wako Pure Chemical Industries, Ltd.) was added per 100 parts by mass of resin solids, and a solvent (ethyl acetate) was added as appropriate to adjust the solids concentration to 15%. The mixture was then stirred at 50°C for 24 hours under an air atmosphere to obtain a pressure-sensitive adhesive solution A (pressure-sensitive adhesive composition) containing the acrylic polymer A. Next, 12 parts by mass of a polyisocyanate compound (trade name "Takenate D-101E", manufactured by Mitsui Chemicals, Inc.) and 4 parts by mass of a photopolymerization initiator (trade name "Omnirad 651", manufactured by IGM Resins) were added to the pressure-sensitive adhesive solution A, relative to 100 parts by mass of the acrylic polymer A, to prepare a pressure-sensitive adhesive solution A'. The pressure-sensitive adhesive solution A' prepared above was applied to the silicone-treated surface of a PET release liner and heated at 120°C for 2 minutes to crosslink the adhesive, forming a pressure-sensitive adhesive layer with a thickness of 15 μm. Next, a 115 μm-thick ethylene-vinyl acetate copolymer (EVA) film was laminated to the pressure-sensitive adhesive layer surface. After storage at 50°C for 24 hours, the resulting sheet was designated as pressure-sensitive adhesive sheet 1.

[0135] <Adhesive Sheet 2> Adhesive sheet 2 was produced in the same manner as Adhesive Sheet 1, except that in Adhesive Sheet 1, 2EHA was changed to 75 mol % of the total amount of monomers not containing a hydroxyl group, ACMO was changed to 25 mol % of the total amount of monomers not containing a hydroxyl group, KarenzMOI was changed to an amount equivalent to 11 mol % when the total amount of monomers not containing a hydroxyl group was taken as 100 mol %, Omnirad 651 was changed to 3 parts by mass, and Takenate D-101E was changed to 4 parts by mass.

[0136] <Adhesive Sheet 3> Adhesive sheet 3 was produced in the same manner as Adhesive Sheet 1, except that in Adhesive Sheet 1, 2EHA was changed to 100 mol % of the total amount of monomers not containing a hydroxyl group, ACMO was changed to 0 mol % of the total amount of monomers not containing a hydroxyl group, KarenzMOI was changed to an amount equivalent to 16 mol % when the total amount of monomers not containing a hydroxyl group was taken as 100 mol %, Omnirad 651 was changed to 3 parts by mass, and Takenate D-101E was changed to 4 parts by mass.

[0137] <Adhesive Sheet 4> Adhesive sheet 4 was produced in the same manner as Adhesive Sheet 1, except that Omnirad 651 in Adhesive Sheet 1 was changed to a thermal polymerization initiator (manufactured by NOF Corporation, trade name: Niper (registered trademark) BW).

[0138] <Formation of an epitaxial metal film by sputtering on a single crystal substrate surface> The c-plane (0001) of sapphire (α-Al2O3) purchased from Adamant Namiki Precision Jewel Co., Ltd. was used as the single crystal substrate. The above single crystal substrate was placed in the chamber of an RF magnetron sputtering device (Shibaura Mechatronics CFS-4ES), and Cu metal was sputtered onto the entire surface of the single crystal substrate (Ar atmosphere, standard vacuum of 0.6 Pa). This resulted in the epitaxial deposition of a Cu film with a thickness of 1000 nm, yielding a Cu / sapphire substrate.

[0139] <Graphene CVD deposition> A quartz tube (substrate size: 200 mm) was set in a ceramic tube furnace manufactured by Asahi Rika Seisakusho. ２ In the case of an inner diameter of 26 mm and a board size of 7854 mm ２The Cu / sapphire substrate was placed inside the chamber (inner diameter 140 mm for a 4-inch wafer) as a substrate for graphene deposition. The Cu / sapphire substrate had a substrate size of 10 mm x 20 mm or 7854 mm. ２ A 4-inch wafer was used. The temperature was then raised to a predetermined temperature (1000-1075°C) under atmospheric pressure while flowing argon and hydrogen. After reaching the predetermined temperature, the temperature was maintained under the same conditions for 0-3 hours to reduce and smooth the Cu surface. Then, 10-200 ppm of methane was added, and a chemical vapor reaction was carried out for 90 minutes. After the reaction, the substrate was cooled to room temperature (23°C), and the Cu / sapphire substrate (first laminate) on which single-layer graphene had been produced was removed from the quartz tube. Through this reaction, a continuous single-layer graphene film covering the entire Cu surface was formed on the Cu surface. Furthermore, 90% or more of the area of ​​the graphene produced was single-layer.

[0140] <MoS ２ CVD deposition of molybdenum disulfide (MoS), a type of transition metal chalcogenide, was placed inside a quartz tube (inner diameter 26 mm) set in a ceramic tube furnace at Asahi Rika Seisakusho. ２ ) A sapphire substrate (c-plane, manufactured by Kyocera Corporation) was placed as the film-forming substrate. Furthermore, a crucible containing molybdenum trioxide powder, the raw material, was placed in the upstream region of the gas flow relative to the film-forming substrate inside the quartz tube, and a crucible containing sulfur powder was placed further upstream. The sapphire substrates used were 10 mm x 20 mm in size, and 10 to 50 mg of molybdenum trioxide and 50 to 200 mg of sulfur were used. The distance between the sapphire substrate and each crucible was as follows: the sapphire substrate requiring the highest reaction temperature was placed at the center of the tubular furnace, the molybdenum trioxide crucible was placed 10 to 20 cm away from it, and the sulfur crucible was placed 15 to 25 cm away from the molybdenum trioxide crucible. Then, under atmospheric pressure, the sapphire substrate and each crucible were heated to a predetermined temperature (substrate: 850-950°C, molybdenum trioxide: 580-600°C, sulfur: 100-200°C) while argon was flowing, and a chemical vapor reaction was carried out for 1 hour. After the reaction, the substrate was cooled to room temperature (23°C), and then MoS ２The sapphire substrate on which MoS was formed was removed from the quartz tube. ２ was formed on the surface of a sapphire substrate, and a laminate A (first laminate, MoS ２ / sapphire substrate) was obtained.

[0141] Example 1 Area: 200 mm ２ The adhesive sheet 1 was attached to the graphene side of the first laminate using a roller (pressure of 2 kg / 10 mm), and the laminate was autoclaved at 50°C and 5 atmospheres for 30 minutes, and then left to stand at room temperature and normal pressure for 30 minutes to obtain a second laminate. A portion of the adhesive sheet in the outer periphery of the substrate in the second laminate was trimmed with a cutter knife to remove a 5 mm ２ A portion with an exposed Cu / graphene surface of about 450 mJ / cm was produced from the substrate side of the adhesive sheet 1 using a UV irradiator (UM-810 manufactured by Nitto Seiki Co., Ltd.). ２ The UV treatment was performed with an irradiation dose of 1000 nm. The exposed Cu / graphene surface of the second laminate (substrate / graphene / adhesive sheet 1) was clamped with an electrode clip, and a Pt electrode was used as the counter electrode, and an Ag / AgCl electrode was used as the reference electrode. Each was immersed in a 1 M aqueous sodium hydroxide solution and set, and a DC voltage of 4 V was applied using a potentiostat (Vertex 10A manufactured by IVIUM). After voltage application, gas (bubbles) were generated by electrolysis at the interface between the Cu surface and the graphene, and the graphene / adhesive sheet 1 laminate (third laminate) was separated from the Cu / sapphire substrate. The graphene / adhesive sheet 1 laminate (third laminate) was immersed in ion-exchanged water for cleaning, and then attached to a silicon substrate with an oxide film (manufactured by SUMCO Corporation, silicon (crystal plane (100)), surface thermal oxidation, oxide film thickness 300 nm, hereinafter also referred to simply as "silicon substrate") using a roller (pressure of 2 kg / 10 mm) with water, left to stand at room temperature for 24 hours, and baked at 90°C for 30 minutes to obtain a fourth laminate. The graphene was attached to the oxide film (SiO ２) side. The silicon substrate in the fourth laminate was fixed, and the pressure-sensitive adhesive sheet 1 was peeled off at a peel angle of 180 degrees and a peel speed of 300 mm / min using a tensile tester (VPA-H200F, manufactured by Kyowa Interface Science Co., Ltd.), thereby transferring the graphene to the silicon substrate, and a laminate of the silicon substrate and graphene in Example 1 (fifth laminate) was obtained. The fifth laminate is also referred to as a two-dimensional material laminate.

[0142] Example 2 In Example 1, the area of ​​the first laminate was set to 7854 mm ２ (= 4-inch wafer), the size of the silicon substrate to be transferred is 12100 mm ２ A laminate (fifth laminate) of the silicon substrate and graphene in Example 2 was obtained in the same manner as in Example 1, except that the dimensions of the substrate were changed to (110 mm x 110 mm).

[0143] Example 3: MoS of laminate A ２ The adhesive sheet 2 was attached to the side of the adhesive sheet 1 with a roller (pressure of 2 kg / 10 mm), and the adhesive sheet 2 was then autoclaved at 50°C and 5 atmospheres for 30 minutes, and then left to stand at room temperature and normal pressure for 30 minutes. A UV irradiator (UM-810 manufactured by Nitto Seiki Co., Ltd.) was used to irradiate the adhesive sheet 2 from the substrate side. ２ After that, the laminate B (second laminate, adhesive sheet / MoS ２ The MoS film was then immersed in water and peeled at a peeling angle of 120° and a peeling speed of 30 mm / min in water at room temperature, and the MoS film was then attached to the adhesive sheet. ２ The laminate C (third laminate, adhesive sheet / MoS ２ ) was obtained. Then, the stack C was ２ The laminate was placed so that the side surface was in contact with a silicon substrate with an oxide film (SUMCO silicon (crystal plane (100)), surface thermal oxidation - oxide film thickness 300 nm), and was adhered with a roller (pressure of 2 kg / 10 mm) using water to form laminate D (fourth laminate, adhesive sheet / MoS ２ After leaving the laminate D at room temperature and normal pressure for 30 minutes, it was baked at 90°C for 30 minutes, and the adhesive sheet 1 was peeled off at a peel angle of 180° and a peel speed of 300 mm / min to obtain the MoS ２The silicon substrate and MoS ２ A laminate E (fifth laminate, two-dimensional material laminate) was obtained.

[0144] Example 4 A laminate of a silicon substrate and graphene in Example 4 (fifth laminate) was obtained in the same manner as in Example 1, except that the adhesive sheet 1 in Example 1 was changed to the adhesive sheet 4, and the second laminate (substrate / graphene / adhesive sheet 4) was heat-treated for 10 minutes in a 150°C constant temperature bath instead of the UV treatment.

[0145] Example 5 The silicon substrate and MoS in Example 5 were fabricated in the same manner as in Example 3, except that adhesive sheet 2 in Example 3 was changed to adhesive sheet 3. ２ A laminate E (fifth laminate) was obtained.

[0146] Comparative Example 1 A laminate of a silicon substrate and graphene in Comparative Example 1 (fifth laminate) was obtained in the same manner as in Example 1, except that UV irradiation was not performed.

[0147] Comparative Example 2 A laminate of a silicon substrate and graphene in Comparative Example 2 (fifth laminate) was obtained in the same manner as in Example 1, except that UV irradiation was performed immediately before peeling off the adhesive sheet 1 from the silicon substrate, rather than before separation from the Cu substrate.

[0148] Comparative Example 3 The silicon substrate and MoS in Comparative Example 3 were prepared in the same manner as in Example 3, except that UV irradiation was not performed before separation from the sapphire substrate, but was performed immediately before peeling off the adhesive sheet 2 from the silicon substrate. ２ A laminate (fifth laminate) was obtained.

[0149] <Tensile Modulus> A 10 mm wide x 20 mm long sample of the pressure-sensitive adhesive sheet / graphene laminate (third laminate) obtained at an intermediate stage in Examples 1 to 5 and Comparative Examples 1 to 3 (Example 2 is a sample cut out from a 4-inch wafer with a central width of 10 mm x length of 20 mm) was chucked at 5 mm above and below in the longitudinal direction with a chuck distance of 10 mm, and pulled at a speed of 50 mm / min. The initial tensile modulus was calculated from the slope at the point where the slope of the stress with respect to strain becomes maximum between 10% strain and 100% strain when the sample was chucked at 5 mm above and below in the longitudinal direction with a chuck distance of 10 mm. This was measured using a tensile tester (AUTOGRAPH AGS-X, manufactured by Shimadzu Corporation), and this was used as the tensile modulus of the laminate (third laminate). Note that since the PMMA / graphene laminate of Comparative Example 1 is a thin layer and difficult to handle, a 50 μm thick cast film of PMMA was separately prepared and measured in the same manner as above to calculate the tensile modulus. The tensile modulus of the substrate was measured and calculated in the same manner as above for the substrate alone prepared during the production of PSA sheets 1 and 2. The tensile modulus of the pressure-sensitive adhesive layer was measured and calculated in the same manner as above for the pressure-sensitive adhesive layer obtained during the production of PSA sheets 1 to 4 before being bonded to the substrate, using a cylindrical sample of 30 mm in length and 1 mm in diameter, with chucks at 10 mm above and below in the length direction, for both the case with and without UV irradiation. The UV treatment was carried out using a UV irradiator (UM-810 manufactured by Nitto Seiki Co., Ltd.) at 450 mJ / cm from the substrate side of the pressure-sensitive adhesive sheet. ２ The heat treatment was carried out by heating at 150°C for 10 minutes in a thermostatic chamber (SPHH-202, manufactured by Espec Corporation). The UV treatment and heat treatment were carried out before rolling the pressure-sensitive adhesive layer into a cylindrical sample. The tensile modulus values ​​were measured at 23°C.

[0150] <Removability of Support Layer> The pressure-sensitive adhesive sheets used in Examples 1 to 5 and Comparative Examples 1 to 3 were each cut to a width of 20 mm and a length of 10 cm, and the release liner was peeled off and removed. Subsequently, the pressure-sensitive adhesive sheet of each example was attached to a silicon wafer (a 4-inch silicon mirror wafer) by pressing it back and forth with a 2 kg roller once, and then left to stand for 30 minutes. Except for Example 4 and Comparative Example 1, the pressure-sensitive adhesive sheets were irradiated with 450 mJ / cm from the substrate side of the pressure-sensitive adhesive sheet using a UV irradiator (UM-810, manufactured by Nitto Seiki Co., Ltd.). ２UV irradiation was performed at an irradiation dose of 1000 nm. In Example 4, heat treatment was performed in a thermostatic chamber (SPHH-202, manufactured by Espec Corporation) at 150°C for 10 minutes. Using a tensile tester (VPA-H200F, manufactured by Kyowa Interface Science Co., Ltd.), the peel force when peeled at a peel angle of 180° and a peel speed of 300 mm / min was measured as removability A (180° peel force from silicon wafer) (N / 20 mm). The measurement temperature was 23°C. In addition, in Examples 1 to 5 and Comparative Examples 1 to 3, the peel force when actually peeling the pressure-sensitive adhesive sheet from the silicon substrate was measured as removability B (180° peel force when releasing two-dimensional material from silicon substrate) (N / 10 mm). The measurement temperature was 23°C.

[0151] <Transfer rate> The silicon substrates and graphene or MoS obtained in Examples 1 to 5 and Comparative Examples 1 to 3 were ２ The laminate (fifth laminate) of the transferred material (oxide film (SiO ２ Graphene or MoS remaining on the surface of the ２ The image was obtained as a digital image using an optical microscope (VHX-8000, manufactured by Keyence Corporation). The digital image was an observation image with an objective lens at 500x magnification, and had a size of 10 mm length x 20 mm width (7854 mm in Example 2). ２ (=4-inch wafer size)) of graphene or MoS ２ Images were acquired from nine locations on the side surface of the substrate. Specifically, the center of the substrate was designated as point E, and two points 6.5 mm (50 mm in Example 2) away from point E on the left and right were designated as points D and F, respectively. Furthermore, points 2.5 mm (50 mm in Example 2) away from point D on the top and bottom were designated as points A and G, respectively. Similarly, points 2.5 mm (50 mm in Example 2) away from point E on the top and bottom were designated as points B and H, respectively, and points 2.5 mm (50 mm in Example 2) away from point F on the top and bottom were designated as points C and I, respectively. From the digital images acquired for each of points A to I, RGB separation and binarization analysis of each component image were performed using a 500 μm × 300 μm range using the software "imageJ," and the amount of graphene or MoS present in the corresponding digital image was analyzed. ２ The area ratio of graphene or MoS in the digital images of nine points A to I was calculated as a percentage.２ The average value of the area ratio was taken as the transfer rate (%).

[0152] <Mobility> For each of the laminates (fifth laminates) of silicon substrate and graphene obtained in Examples 1 to 2 and 4 and Comparative Examples 1 and 2, a resist (AZ5214-E, manufactured by Clariant) was formed on the graphene by spin casting (300 rpm, 5 seconds, followed by 3300 rpm, 30 seconds). Note that the processes from resist coating to pattern exposure and removal of the unexposed portions of the resist were carried out in a UV-blocking environment. Subsequently, the laminate was baked on a hot plate at 90°C for 1 minute to remove excess solvent.

[0153] The laminate on which the resist was formed was set in an exposure device (PALET DDB-701, manufactured by Neoark Corporation) and irradiated with light at 60 mW / cm to form a pattern in the shape of the transistor channel. ２ The image was exposed to light for 1.1 seconds.

[0154] To carry out the subsequent development process, the exposed laminate was immersed in an NMD-3 (2.38%, organic alkaline aqueous solution, manufactured by Tokyo Ohka Kogyo Co., Ltd.) solution for 100 seconds while gently moving it, and then immersed in water to wash off the NMD-3, thereby removing the unexposed portions of the resist.

[0155] The fifth stack, on whose surface the transistor channel-shaped pattern remained, was subjected to an ashing treatment (Yamato Scientific, PR-500) to remove the graphene in the areas not covered by the pattern.The pattern was then removed with acetone to obtain the graphene channel shape.

[0156] After the channel processing was completed, a resist film was again formed on the fifth stack by spin casting, and an exposure device was used to form a pattern so that the resist covered all areas except for the areas where the electrodes on both ends of the graphene channel were planned, and a development process was then performed.

[0157] On the fifth laminate in which the graphene channel had been processed and which was covered with resist except for the area intended for the electrode, a vacuum deposition apparatus (KB-750 manufactured by Kenix) was used to deposit 10 －４Under a reduced pressure of 10 Pa, Ni was evaporated to a thickness of 10 Å, and then Au was evaporated to a thickness of 300 Å.

[0158] By removing the resist with acetone, Ni / Au electrodes including a source electrode S and a drain electrode D were formed at each end of the graphene channel, thereby fabricating a field effect transistor using graphene as the channel material.

[0159] A field effect transistor was fabricated from the laminate and placed in a chamber equipped with a measurement probe (MJ-8, manufactured by Apollo Wave Co., Ltd.). －４ The graphene channel surface was cleaned by treatment at 200°C for 15 hours under a reduced pressure of 0.1 Pa or less. The laminate was returned to room temperature while still under reduced pressure, and measurement probes were applied to the source electrode S and drain electrode D. A semiconductor parameter analyzer (Keysight, B1500A) was used to measure the current (Id) that flowed when 20 mV was applied between S and D while applying a variable voltage (Vg) of -40 to 40 V to the silicon (Si) substrate that served as the gate electrode G, and the electron mobility of the graphene was calculated.

[0160] The measurement results for Examples 1 to 2 and 4 and Comparative Examples 1 and 2 are summarized in the following Table 1. Note that the "tensile modulus of laminate" in Table 1 refers to the tensile modulus of the graphene / adhesive sheet laminate (third laminate).

[0161]

[0162] The results of the measurements of Examples 3 and 5 and Comparative Example 3 are summarized in Table 2 below. In Table 2, the "tensile modulus of the laminate" refers to the tensile modulus of the MoS ２ / The tensile modulus of elasticity of the pressure-sensitive adhesive sheet laminate (third laminate).

[0163]

[0164] In Examples 1 to 4, an adhesive tape was used as a removable support layer, and a bubble-forming step was performed after the pre-curing step during the manufacturing process, which enabled the support layer to be easily peeled off from the graphene, enabled graphene to be transferred at a high transfer rate, and the mobility of the transferred graphene was also high. On the other hand, in Comparative Examples 1 and 2, which did not include a pre-curing step during the manufacturing process, the graphene transfer rate was lower than in Examples 1 to 4.

[0165] In Examples 3 and 5, adhesive tape was used as a removably support layer, and a liquid peeling step was performed after pre-curing during the manufacturing process, so that the support layer was made of MoS ２ It can be easily peeled off from MoS ２ On the other hand, in Comparative Example 3, which did not include a pre-curing step (post-curing step) in the manufacturing process, the MoS ２ The transcription rate was low.

[0166] This application is based on a Japanese patent application (Patent Application No. 2023-223307) filed on December 28, 2023, the contents of which are incorporated herein by reference.

[0167] The laminate manufacturing method, two-dimensional material laminate manufacturing method, and laminate manufacturing apparatus including two-dimensional materials of the present invention are useful for a laminate manufacturing method, two-dimensional material laminate manufacturing method, and laminate manufacturing apparatus including two-dimensional materials that can manufacture a laminate that can efficiently transfer two-dimensional materials at a high transfer rate, even if the two-dimensional materials have a large area.

[0168] 101: Laminate (first laminate) 102: Laminate (second laminate) 103: Laminate (third laminate) 104: Laminate (fourth laminate) 10: Support layer 11: Base material 12: Pressure-sensitive adhesive layer 21: First substrate 30: Two-dimensional material 40: Second substrate 105: Two-dimensional material laminate (fifth laminate)

Claims

1. A preparation step of preparing a laminate in which a first substrate, a two-dimensional material, and a cured support layer are laminated in this order; and a separation step of separating the laminate including the support layer and the two-dimensional material from the first substrate. A method for manufacturing a laminate.

2. The method for manufacturing a laminate according to claim 1, wherein the preparation step includes a preliminary step of forming the two-dimensional material on the first substrate. A method for manufacturing a laminate.

3. The method for manufacturing a laminate according to claim 1, wherein the preparation step includes a support layer adhesion step of adhering the support layer that is cured by receiving supply of predetermined energy or a substance to the two-dimensional material on the first substrate. A method for manufacturing a laminate.

4. The method for manufacturing a laminate according to claim 1, wherein the preparation step includes a curing step of curing the support layer adhered to the two-dimensional material by supply of predetermined energy or a substance. A method for manufacturing a laminate.

5. The method for manufacturing a laminate according to claim 4, wherein the curing step supplies actinic rays as the predetermined energy. A method for manufacturing a laminate.

6. The method for manufacturing a laminate according to claim 1, including a bubble formation step of forming bubbles between the first substrate and the two-dimensional material before the separation step. A method for manufacturing a laminate.

7. The method for manufacturing a laminate according to claim 6, wherein the separation step separates the laminate including the support layer and the two-dimensional material from the first substrate by forming the bubbles or by pulling at least one of the support layer and the first substrate after forming the bubbles. A method for manufacturing a laminate.

8. The method for manufacturing a laminate according to claim 1, wherein as the separation step, the laminate in which the first substrate, the two-dimensional material, and the cured support layer are laminated in this order is immersed in a liquid, and at least one of the support layer and the first substrate is pulled in the liquid to peel the laminate including the support layer and the two-dimensional material from the first substrate. A liquid peeling step is performed. A method for manufacturing a laminate.

9. The method for manufacturing a laminate according to claim 1, wherein the support layer is an adhesive tape including an adhesive layer and a base material. A method for manufacturing a laminate.

10. A method for manufacturing a two-dimensional material laminate, comprising a transfer step of peeling the support layer of the laminate obtained by the method for manufacturing a laminate according to any one of claims 1 to 9 from the two-dimensional material in contact with the second substrate, thereby transferring the two-dimensional material onto the second substrate to obtain a two-dimensional material laminate including the second substrate and the two-dimensional material.

11. A method for manufacturing a two-dimensional material laminate according to claim 10, comprising a placement step of placing the laminate on the second substrate such that the surface on the two-dimensional material side is in contact with the second substrate.

12. A manufacturing apparatus for a laminate including a two-dimensional material, comprising: a curing unit that cures the support layer attached to the two-dimensional material by supplying a predetermined energy or substance in a laminate in which a first substrate, a two-dimensional material, and a support layer are laminated in this order; and a separation unit that separates the laminate including the support layer and the two-dimensional material from the first substrate.

13. A manufacturing apparatus for a laminate including a two-dimensional material according to claim 12, further comprising a preliminary preparation unit that forms the two-dimensional material on the first substrate.

14. A manufacturing apparatus for a laminate including a two-dimensional material according to claim 12, further comprising a support layer attaching unit that attaches the support layer that cures by receiving the supply of the predetermined energy or the substance to the two-dimensional material on the first substrate.

15. A manufacturing apparatus for a laminate including a two-dimensional material according to claim 12, wherein the separation unit is composed of at least a bubble forming unit that forms bubbles between the first substrate and the two-dimensional material, and separates the laminate including the support layer and the two-dimensional material from the first substrate by forming the bubbles or by pulling at least one of the support layer and the first substrate after forming the bubbles.

16. A manufacturing apparatus for a laminate including the two-dimensional material according to claim 15, further comprising a placing portion for placing the laminate including the support layer and the two-dimensional material, which is separated from the first substrate by the separating portion, on the second substrate such that the surface of the laminate on the two-dimensional material side contacts the second substrate. A manufacturing apparatus for a laminate including a two-dimensional material.

17. A manufacturing apparatus for a laminate including the two-dimensional material according to claim 12, further comprising a transferring portion for transferring the two-dimensional material onto the second substrate by peeling the support layer of the laminate including the support layer and the two-dimensional material, which is separated from the first substrate by the separating portion, from the two-dimensional material contacting the second substrate, to obtain a two-dimensional material laminate including the second substrate and the two-dimensional material. A manufacturing apparatus for a laminate including a two-dimensional material.

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