Planar heating element and manufacturing method thereof

Abstract

According to various embodiments disclosed herein, a planar heating element comprises: a substrate; a transfer layer on the substrate; a graphene layer on the transfer layer; an encapsulation layer configured to seal the graphene layer; and a connection layer between the graphene layer and the encapsulation layer, the connection layer being configured to connect the graphene layer and the encapsulation layer. The graphene layer and the connection layer include empty spaces configured to be filled with the encapsulation layer to connect the transfer layer and the encapsulation layer.

Description

Planar heating element and method of manufacturing the same

[0001] The present disclosure relates to a planar heating element and a method for manufacturing the same.

[0002] Planar heating elements are utilized in various fields because they generate radiant heat through the conduction of electricity, thereby eliminating concerns about air pollution in the surrounding heating space, ensuring hygiene, and producing no noise. As heating elements that generate heat evenly across a wide surface, planar heating elements can achieve more uniform and faster heating by dispersing heat over a large area, unlike conventional linear heating elements that generate heat in a linear shape. Planar heating elements can be manufactured using materials that possess the property of generating heat when electricity is passed through them (e.g., carbon materials such as carbon nanotubes (CNT) or graphene).

[0003] Graphene is a structure in which carbon atoms form a two-dimensional plane and can possess high electron mobility, high thermal conductivity, high strength, low absorption of visible light, high light transmittance, and flexibility. Due to these properties of graphene, attempts to utilize graphene as a planar heating element (e.g., a transparent planar heating element) are ongoing.

[0004] The information described above may be provided as related art for the purpose of aiding understanding of the present disclosure. No claim or determination is made as to whether any of the foregoing may be applied as prior art related to the present disclosure.

[0005] There have been many attempts to mass-produce graphene using planar heating elements (e.g., transparent planar heating elements), but it has been difficult to achieve reliable performance as a heating element due to problems such as graphene being easily lost due to external impact, the absence of a material that adheres to the graphene, and / or degradation caused by graphene loss or oxidation when exposed to an atmospheric environment for a long time or used in a high-temperature environment (e.g., a temperature environment of about 500°C or higher applied to household appliances).

[0006] The embodiments of the present disclosure provide a planar heating element utilizing graphene that can be stably commercialized and / or mass-produced, and a method for manufacturing the same.

[0007] The technical problems to be solved by the present disclosure are not limited to those mentioned above, and other unmentioned technical problems will be understood by those skilled in the art from the description below. Various embodiments of the present disclosure are provided to solve or at least alleviate the problems mentioned above.

[0008] According to various embodiments of the present disclosure, a planar heating element comprises a substrate, a transfer layer on the substrate, a graphene layer on the transfer layer, an encapsulation layer configured to seal the graphene layer, and a connecting layer between the graphene layer and the encapsulation layer configured to connect the graphene layer and the encapsulation layer. The graphene layer and the connecting layer include an empty space configured to be filled with the encapsulation layer to connect the transfer layer and the encapsulation layer.

[0009] According to various embodiments of the present disclosure, a method for manufacturing a planar heating element comprises the steps of forming a substrate, forming a transfer layer on the substrate, forming a graphene layer on the transfer layer, forming a connecting layer on the graphene layer, and forming an encapsulation layer configured to seal the graphene layer. The connecting layer is configured to connect the graphene layer and the encapsulation layer. The graphene layer and the connecting layer include an empty space configured to be filled with the encapsulation layer so as to connect the transfer layer and the encapsulation layer.

[0010] The planar heating element and the method for manufacturing the same according to various embodiments of the present disclosure can stably implement a planar heating element to reduce or prevent the loss or oxidation of graphene, thereby ensuring reliability of the planar heating element.

[0011] Planar heating elements and methods for manufacturing the same according to various embodiments of the present disclosure can reduce differences in heating performance between planar heating elements, thereby improving commercialization and / or mass production of planar heating elements.

[0012] In addition, effects that can be obtained or predicted by various embodiments of the present disclosure will be disclosed directly or implicitly in the detailed description of the embodiments of the present disclosure.

[0013] The above and other aspects, features, and advantages of the embodiments of the present disclosure will become more apparent from the following detailed description taken together with the accompanying drawings.

[0014] FIG. 1 is a drawing showing a planar heating element according to various embodiments of the present disclosure.

[0015] FIG. 2 is a cross-sectional view of a planar heating element cut along line A-A' of FIG. 1 according to various embodiments of the present disclosure.

[0016] FIG. 3 is a cross-sectional view of a planar heating element cut along line B-B' of FIG. 1 according to various embodiments of the present disclosure.

[0017] FIG. 4 is a diagram showing the manufacturing flow of a planar heating element according to various embodiments of the present disclosure.

[0018] FIG. 5 is a graph showing the temperature generated from a planar heating element of a comparative example and a planar heating element of the present disclosure with respect to an applied voltage according to various embodiments of the present disclosure.

[0019] FIG. 6 is a diagram showing the dispersion of surface resistance by region of a comparative example planar heating element according to various embodiments.

[0020] FIG. 7 is a graph showing the correlation between the surface resistance and heating element resistance of comparative examples of planar heating elements according to various embodiments.

[0021] FIG. 8 is a drawing showing a planar heating element according to various embodiments of the present disclosure.

[0022] FIG. 9 is a graph showing the variation in heating element resistance between planar heating elements of comparative examples according to various embodiments of the present disclosure and the variation in heating element resistance between planar heating elements of the present disclosure.

[0023] Various embodiments of the present disclosure are described in more detail below. The following description is provided to facilitate a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents, with reference to the accompanying drawings. While various specific details are included to aid understanding, they should be considered merely illustrative. Accordingly, those skilled in the art will recognize that various changes and modifications to the various embodiments described herein may be made without departing from the scope and spirit of the present disclosure. Furthermore, descriptions of known functions and configurations may be omitted for clarity and brevity.

[0024] The terms and words used in the following description and claims are not limited to their bibliographic meanings and are used merely to enable the inventor to understand the present disclosure clearly and consistently. Accordingly, it should be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and is not intended to limit the present disclosure as defined by the appended claims and their equivalents.

[0025] The various embodiments of the present disclosure and the terms used therein are not limited to the specific embodiments of the technical features described in the present disclosure. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of said items unless the relevant context clearly indicates otherwise. In the present disclosure, phrases such as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B or C,” “at least one of A, B and C,” and “at least one of A, B, or C” may each include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as “first,” “second,” or “first” or “second” may be used simply to distinguish a corresponding component from other corresponding components and do not limit the corresponding components in any other aspect (e.g., importance or order). Where one element (e.g., a first component) is referred to as "coupled" or "connected" to another element (e.g., a second component), with or without the term "functionally," said element may be connected to said other element directly or indirectly (e.g., through a third component).

[0026] Each of the components described above may include a single or multiple entities. One or more of the aforementioned components may be omitted, or one or more other components may be added. Generally or additionally, multiple components may be integrated into a single component. In such a case, the integrated component may perform one or more functions of each of the multiple components in the same or similar manner as those performed by the corresponding components among the multiple components prior to the integration.

[0027] In the present disclosure, "placed on XX" may be understood as being placed adjacent to or in substantial contact with XX, coupled to XX, or included in XX.

[0028] In the present disclosure, "located on XX" may be understood as being located adjacent to or in substantial contact with XX, located on XX, or included in XX.

[0029] In the present disclosure, where a first component (or region, layer, part, etc.) is described as being "on," "connected," or "joined" to a second component, it may be understood that it may be directly placed, connected, or joined to the second component, or that a third component may be placed between them.

[0030] In the present disclosure, “ZZ between XX and YY” may be understood as ZZ being positioned in substantial contact with XX or YY or ZZ being directly coupled to XX or YY. “ZZ between XX and YY” may be understood as ZZ being positioned between XX and YY with at least one other component between XX and ZZ and / or at least one component between YY and ZZ in between. “ZZ between XX and YY” may be understood as at least one other component between XX and ZZ connecting XX and ZZ and / or at least one other component between YY and ZZ connecting YY and ZZ.

[0031] In this disclosure, unless otherwise noted, "conductivity" may be understood as "electrical conductivity" and "nonconductivity" may be understood as "electrical insulation." In context, or where thermal properties are mentioned, "conductivity" may be understood as "thermal conductivity."

[0032] In this disclosure, terms such as "above," "upper," "upper," "lower," "lower," or "lower" may be used to describe the relationships between components illustrated in the drawings. These terms are relative concepts and may be described based on the directions indicated in the drawings.

[0033] In the drawings of the present disclosure, the thickness, proportion, and / or dimensions of the components are for the purpose of effectively illustrating the technical content and are not limited to the thickness, proportion, and / or dimensions depicted.

[0034] In this disclosure, where the term “substantially” is used to define a structural part (structure or structural element), expressions including the term “substantially” are understood or interpreted as technical features produced within the technical tolerances of the method used to manufacture them. Additionally, the expression “comprising” implies that a specific effect or result can be obtained within a specific tolerance, and that a person skilled in the art knows how to obtain said tolerance.

[0035] In the present disclosure, the term “and / or” may be understood to include all of one or more combinations that the associated components may define.

[0036] The "comparative examples" mentioned in this disclosure are provided merely for comparison with the embodiments of this disclosure and do not constitute prior art to the various embodiments of this disclosure.

[0037] FIG. 1 is a drawing showing a planar heating element (1) according to various embodiments of the present disclosure.

[0038] FIG. 2 is a cross-sectional view of a planar heating element (1) cut along line A-A' of FIG. 1 according to various embodiments of the present disclosure.

[0039] FIG. 3 is a cross-sectional view of a planar heating element (1) cut along line B-B' of FIG. 1 according to various embodiments of the present disclosure.

[0040] It is understood in this disclosure that any combination of features and / or embodiments disclosed in connection with FIGS. 1, 2, and 3 is conceived and included. Any combination of features described below in connection with FIGS. 1, 2, and 3 may be considered to be included in this disclosure as specific examples.

[0041] Referring to FIGS. 1, 2, and 3, the planar heating element (1) may include a board or substrate (11), an imprint layer (12), a graphene layer (13), a connecting layer (14), and an encapsulation layer (15). The planar heating element (1) may include a first electrode (21) and a second electrode (22).

[0042] According to various embodiments, the substrate (also referred to as a base substrate or base board, base plate, base member, or base) (11) may be understood as a support capable of maintaining the shape of the planar heating element (1). The substrate (11) may be understood as a target substrate or target plate on which a layer for imprinting (12), a graphene layer (13), a connecting layer (14), and an encapsulation layer (15) are to be placed. The substrate (11) may be formed substantially flat as illustrated, but is not limited thereto and may be formed in a curved shape, or in a shape that is a combination of a flat shape and a curved shape. The substrate (11) may be formed of a non-metallic material and / or a metallic material. The substrate (11) may be implemented to reduce the weight of the planar heating element (1) and slim the planar heating element (1), while ensuring the strength of the planar heating element (1). The substrate (11) can be implemented to have flexibility so that it is easy to form various shapes, such as curved shapes.

[0043] According to various embodiments, the substrate (11) may be implemented to reduce damage or deformation caused by heat generated from the graphene layer (13) (also called a heating layer or heating part). The substrate (11) may be durable against high temperatures, for example, about 500°C or higher.

[0044] According to various embodiments, the substrate (11) is made of a material that can reduce changes in volume caused by heat (or temperature change) provided in the process of forming the graphene layer (13), thereby enabling the graphene layer (13) to be formed while reducing structural defects.

[0045] According to various embodiments, the substrate (11) may be formed of ceramic glass or quartz glass (also called quartz) that is transparent and has high temperature durability. The material of the substrate (11) is not limited thereto.

[0046] According to various embodiments, the substrate (11) may include a first surface (101) and a sixth surface (106) facing in a direction opposite to the first surface (101). The substrate (11) may have a first thickness (T1) corresponding to the distance between the first surface (101) and the sixth surface (106), and the first thickness (T1) may be about 4 mm (millimeter). The first thickness (T1) of the substrate (11) is not limited thereto.

[0047] According to various embodiments, the surface roughness of the planar heating element (1) may be influenced by the substrate (11) forming the shape of the planar heating element (1). A transfer layer (12) for transferring a graphene layer (13) may be placed (or bonded) to a first surface (101) of the substrate (11), and the first surface (101) may be configured to have a surface roughness such that the substrate (11) and the transfer layer (12) can reduce the air gap and adhere to each other. The first surface (101) of the substrate (11) may have, for example, a centerline average roughness (Ra) of about 0.168 μm (micrometer) to about 0.192 μm, but is not limited thereto.

[0048] According to various embodiments, a transfer layer (12) disposed (or bonded) on a first surface (101) of a substrate (11) may include a second surface (102) that is substantially or at least partially parallel to the first surface (101) of the substrate (11), and the second surface (102) may have a second thickness (T2) spaced apart from the first surface (101). The transfer layer (12) may be configured to stably transfer a graphene layer (13). The transfer layer (12) may be configured so that the graphene layer (13) is stably adhered to the transfer layer (12) while reducing the air gap between the transfer layer (12) and the graphene layer (13) when forming (e.g., transferring) the graphene layer (13). Compared to a comparative example in which a graphene layer (13) is transferred onto a first surface (101) of a substrate (11), the transfer layer (12) can improve the transfer efficiency of the graphene layer (13) by forming a second surface (102) with improved surface roughness compared to the surface roughness of the first surface (101) of the substrate (11). In various embodiments, the second surface (102) of the transfer layer (12) may be flatter than the first surface (101) of the substrate (11). In various embodiments, the second surface (102) of the transfer layer (12) may have a smaller surface roughness value than the first surface (101) of the substrate (11). The second surface (102) of the transfer layer (12) may have, for example, a centerline average roughness (Ra) of about 0.074 μm to about 0.86 μm, but is not limited thereto.

[0049] According to various embodiments, the transfer layer (12) may be formed as a thin film capable of slimming the planar heating element (1). The transfer layer (12) may be formed with a second thickness (T2) of, for example, about 0.1 μm to about 1.0 μm, but is not limited thereto.

[0050] According to various embodiments, the transfer layer (12) may be implemented to reduce damage or deformation caused by heat generated from the graphene layer (13). The transfer layer (12) may have durability to reduce or prevent breakage or deformation at high temperatures, for example, about 500°C or higher. The transfer layer (12) may be implemented with a material that can reduce changes in volume caused by heat (or temperature changes) applied during the process of forming the graphene layer (13) (e.g., transfer), thereby improving the transfer of the graphene layer (13) while reducing structural defects or failures.

[0051] According to various embodiments, the transfer layer (12) may be implemented as an oxidized inorganic layer (e.g., a layer containing an oxidized inorganic layer). The transfer layer (12) may include, for example, silicon dioxide (SiO2). The transfer layer (12) (e.g., a silicon dioxide layer) may be formed, for example, through inorganic polysilazane. The inorganic polysilazane may be perhydropolysilazane (PHPS), which is an inorganic polymer composed of a combination of silicon and nitrogen. By coating the inorganic polysilazane onto the first surface (101) of the substrate (11) and then curing (e.g., heat curing), the inorganic polysilazane may react with moisture (H2O) or oxygen (O2) to form a silicon dioxide layer. Inorganic polysilazane can have excellent adhesion and enable the formation of a uniform layer of a thin film (e.g., a coating film), thereby allowing a uniform silicon dioxide layer of the thin film to be formed. In various embodiments, the transfer layer (12) may be implemented as another inorganic oxide layer, not limited to a silicon dioxide layer.

[0052] According to various embodiments, the transfer layer (12) may be implemented as a metal oxide layer (e.g., a layer containing a metal oxide). The metal oxide is, for example, aluminum oxide (e.g., Al2O3 (aluminum oxide)), titanium oxide (e.g., TiO2 (titanium oxide)), or silicon nitride (e.g., SiN x It may include (silicon nitride), but is not limited thereto. In various embodiments, the transfer layer (12) may be implemented as a multilayer formed of layers of different metal oxides.

[0053] According to various embodiments, the graphene layer (13) may be disposed (e.g., transferred) on a second surface (102) of the transfer layer (12). The graphene layer (13) may include a third surface (103) that is substantially or at least partially parallel to the second surface (102) of the transfer layer (12), and the third surface (103) may have a third thickness (T3) spaced apart from the second surface (102). The third thickness (T3) may be about 0.3 nm (nanometer), but is not limited thereto. The graphene layer (13) may be understood as a layer comprising at least one graphene having a structure (e.g., a lattice structure) in which carbon atoms form a two-dimensional plane. The graphene layer (13) may include, for example, a first graphene (131), a second graphene (132), and a third graphene (133). The first graphene (131) may be placed (or bonded) to the second surface (102) of the transfer layer (12). The second graphene (132) may be placed between the first graphene (131) and the third graphene (133). The third graphene (133) may form the third surface (103). The number of graphenes included in the graphene layer (13) is not limited thereto. In the first graphene (131), the second graphene (132), and the third graphene (133), each carbon atom may form a hexagonal lattice and may have a shape in which carbon atoms are located at the vertices of the hexagon (e.g., honeycomb structure or honeycomb lattice). The first graphene (131), the second graphene (132), and / or the third graphene (133) are thin films made of carbon atoms (thickness of about 0.2 μm) and may have high physical and chemical stability. The first graphene (131), the second graphene (132), and / or the third graphene (133) conduct electricity about 100 times better than copper and can move electrons about 100 times faster than single-crystal silicon used in semiconductors.The first graphene (131), the second graphene (132), and / or the third graphene (133) can be about 200 times stronger than steel and have about 2 times greater thermal conductivity than diamond. The first graphene (131), the second graphene (132), and / or the third graphene (133) can be elastic and can substantially not lose their electrical properties when stretched or bent.

[0054] According to various embodiments, the first graphene (131), the second graphene (132), and / or the third graphene (133) may have an electron mobility of about 200,000 cm² / V·s. The first graphene (131), the second graphene (132), and / or the third graphene (133) may have a thermal conductivity of about 5000 W / m·K or about 5300 W / m·K. The first graphene (131), the second graphene (132), and / or the third graphene (133) may have a Young's modulus of about 1.0 TPa (terapascal). The first graphene (131), the second graphene (132), and / or the third graphene (133) may have a tensile strength of about 130 GPa (gigapascal). The first graphene (131), the second graphene (132), and / or the third graphene (133) may have an allowable current density of about 108 A / cm². The first graphene (131), the second graphene (132), and / or the third graphene (133) may have a very low absorption amount for visible light and may have a transmittance of about 97.7% for light having a wavelength of about 550 μm.

[0055] According to various embodiments, the first graphene (131), the second graphene (132), and / or the third graphene (133) may have a thickness of about 0.2 nm, but are not limited thereto.

[0056] According to various embodiments, the graphene layer (13) can be formed on the second surface (102) of the transfer layer (12) through a CVD (chemical vapor deposition) process.

[0057] According to various embodiments, the connecting layer (14) may be disposed (or bonded) to the third surface (103) of the graphene layer (13). The connecting layer (14) may include a fourth surface (104) that is substantially or at least partially parallel to the third surface (103) of the graphene layer (13), and the fourth surface (104) may have a fourth thickness (T4) spaced apart from the third surface (103). The connecting layer (14) may be configured to stably connect the graphene layer (13) and the encapsulation layer (15). The connecting layer (14) may be configured so that the encapsulation layer (15) is stably adhered to the connecting layer (14) while reducing the air gap between the graphene layer (13) and the encapsulation layer (15).

[0058] According to various embodiments, the connecting layer (14) may be configured to form a chemical bond (also referred to as a chemical interaction) and / or a physical bond (also referred to as a physical interaction) between the connecting layer (14) and the encapsulating layer (15). The chemical bond between the connecting layer (14) and the encapsulating layer (15) may be understood as a phenomenon in which the connecting layer (14) and the encapsulating layer (15) are chemically bonded (e.g., a covalent bond in which atoms bond by sharing electron pairs with each other, or a bond between molecules (cross-linking)). The physical bond between the connecting layer (14) and the encapsulating layer (15) may be understood as a phenomenon in which molecules of the connecting layer (14) and molecules of the encapsulating layer (15) are bonded by a force of attraction (e.g., intermolecular force) between them. The bonding force between the connecting layer (14) and the encapsulating layer (15) may be determined by a balance between cohesion force and interfacial force. The cohesive force at the interface between the connecting layer (14) and the encapsulating layer (15) can be understood, for example, as the strength after the material for the encapsulating layer (15) has cured. The interfacial bonding force at the interface between the connecting layer (14) and the encapsulating layer (15) can be understood as the physical interaction between the connecting layer (14) and the encapsulating layer (15). The bonding force between the connecting layer (14) and the encapsulating layer (15) can be understood as the adhesion force (or adhesive strength) (e.g., maximum tensile stress) measured at the interface between the connecting layer (14) and the encapsulating layer (15).

[0059] According to various embodiments, the connecting layer (14) may comprise graphene oxide, to which oxygen atoms have been added to graphene. The connecting layer (14) may, for example, be a single layer of graphene oxide. A double layer structure comprising a graphene layer (13) and a graphene oxide layer (e.g., the connecting layer (14)) may be formed by placing a base graphene layer (e.g., the base graphene layer (410) of FIG. 4) on the second surface (102) of the transfer layer (12) (e.g., by a CVD process) and then oxidizing the surface of the base graphene layer. The base graphene layer may be understood as at least one graphene transferred to the second surface (102) of the transfer layer (12) prior to the oxidation process, serving as a basis for forming the graphene layer (13) and the graphene oxide layer. The graphene oxide layer may be formed, for example, through light having a specified wavelength (e.g., UV (ultra violet)), but is not limited thereto. The graphene layer (13) can be understood as a relatively pure graphene layer compared to the graphene oxide layer. The graphene oxide layer may have a relatively lower charge mobility than the graphene layer (13) or may have substantially insulating properties. The graphene oxide layer may induce or form chemical bonds and / or physical bonds to the encapsulation layer (15). A third side (103) of the graphene layer (13) may be included at the boundary between the graphene layer (13) and the graphene oxide layer (e.g., the connecting layer (14)).

[0060] According to various embodiments, the connecting layer (14) is not limited to the graphene oxide layer and can be formed of amorphous carbon, hexagonal boron nitride (h-BN), or molybdenum disulfide (MoS2). For example, after placing the graphene layer (13) on the second side (102) of the transfer layer (12) (e.g., transfer), the connecting layer (14) can be placed on the third side (103) of the graphene layer (13).

[0061] According to various embodiments, the encapsulation layer (15) may be configured to protect the graphene layer (13). The encapsulation layer (15) may be configured to block oxygen to the graphene layer (13) to reduce or prevent oxidation of the graphene layer (13). The encapsulation layer (15) may form at least a portion of the outer surface of the planar heating element (1) together with the substrate (11). The encapsulation layer (15) may include a first portion (151) and a second portion (152). The first portion (151) of the encapsulation layer (15) may be placed (or bonded) to the fourth surface (104) of the connecting layer (14). The second portion (152) of the encapsulation layer (15) extends from the first portion (151) and may be connected to the transfer layer (12). A layer structure comprising a graphene layer (13) and a connecting layer (14) (hereinafter referred to as a double layer structure (16) of a graphene layer-connecting layer) may include a side surface surrounding the second side (102) of the transfer layer (12) and the fourth side (104) of the connecting layer (14), and a second portion (152) of the encapsulation layer (15) may be disposed on the side surface and connected to the transfer layer (12). A first portion (151) of the encapsulation layer (15) may include a fifth side (105) that is substantially or at least partially parallel to the fourth side (104) of the connecting layer (14), and the fifth side (105) may have a fifth thickness (T5) spaced apart from the fourth side (104). When viewed from above on the fifth side (105) of the transfer layer (12), the transfer layer (12) may include a second border region (1201) that is extended beyond the double layer structure (16) of the graphene layer-connecting layer. A second portion (152) of the encapsulation layer (15) may be connected to the second border region (1201) of the transfer layer (12). When viewed from above on the fifth side (105) of the transfer layer (12), it can be understood as (when viewed in a direction substantially orthogonal to the fifth side (105)) (e.g., when viewed in the negative direction of the z-axis).The second edge region (1201) of the transfer layer (12) may be supported by the first edge region (1101) of the substrate (11). The graphene layer (13) and the connecting layer (14) may be placed between the transfer layer (12) and the encapsulation layer (15), and the graphene layer (13) may be at least partially sealed by the transfer layer (12) and the encapsulation layer (15) to be protected from the outside (e.g., atmospheric environment). The encapsulation layer (15) (or, the transfer layer (12) and / or the encapsulation layer (15)) may reduce or prevent oxidation of the graphene layer (13) due to white rust and / or carbonization in a high-temperature environment (e.g., a high temperature of about 500°C or higher) caused by heat generated from the graphene layer (13).

[0062] According to various embodiments, the encapsulation layer (15) can be implemented to reduce damage or deformation caused by heat generated from the graphene layer (13). The encapsulation layer (15) can be durable against high temperatures, for example, about 500°C or higher.

[0063] According to various embodiments, the bag layer (15) may be formed of the same material as the transfer layer (12) or may be formed of different materials.

[0064] According to various embodiments, the encapsulation layer (15) may include an inorganic oxide. The encapsulation layer (15) may be, for example, a silicon dioxide layer. The silicon dioxide layer may be formed, for example, through an inorganic polysilazane. By coating and curing (e.g., thermal curing) the inorganic polysilazane onto a layer structure comprising a substrate (11), a transfer layer (12), a graphene layer (13), and a connecting layer (14), the inorganic polysilazane may react with moisture or oxygen to form a silicon dioxide layer. The inorganic polysilazane may have excellent adhesion and enable the formation of a uniform layer of a thin film (e.g., a coating film), thereby allowing a uniform silicon dioxide layer of the thin film to be formed. In various embodiments, the encapsulation layer (12) may be implemented as another inorganic oxide layer, not limited to a silicon dioxide layer.

[0065] According to various embodiments, the encapsulation layer (15) may be implemented as a metal oxide layer. The metal oxide layer may include, for example, aluminum oxide, titanium oxide, or silicon nitride, but is not limited thereto. In various embodiments, the encapsulation layer (15) may be implemented as a multilayer formed of layers of different metal oxides.

[0066] According to various embodiments, the first electrode (21) and the second electrode (22) may be placed (or bonded) to the third surface (103) of the graphene layer (13). The first electrode (21) and the second electrode (22) may be electrically connected to the graphene layer (13). The first electrode (21) and the second electrode (22) are terminals configured to transmit current provided from the outside to the graphene layer (13), and may be formed from an electrically conductive material (e.g., a metal plate), such as copper (Cu) or silver (Ag). When current is supplied to the graphene layer (13) through the first electrode (21) and the second electrode (22), the graphene layer (13) may convert electrical energy consumed in the resistance (or resistance component) of the graphene layer (13) into thermal energy.

[0067] According to various embodiments, the third surface (103) of the graphene layer (13) may include a first region (1031), a second region (1032), a third region (1033), a fourth region (1034), and a fifth region (1035). The third region (1033) may be located between the first region (1031) and the second region (1032). The first region (1031) may be located between the third region (1033) and the fourth region (1034). The second region (1032) may be located between the third region (1033) and the fifth region (1035). When viewed from above on the fifth surface (105) of the transfer layer (12), the graphene layer (13) may include a third border region (1301) that overlaps with the second border region (1201) of the transfer layer (12). The fourth region (1034) and the fifth region (1035) of the third surface (103) may be formed by the third border region (1301) of the graphene layer (13). A first electrode (21) may be placed in the first region (1031) included in the third surface (103) of the graphene layer (13). A second electrode (22) may be placed in the second region (1032) included in the third surface (103) of the graphene layer (13). The connecting layer (14) may be placed in a third region (1033) included in the third surface (103) of the graphene layer (13). A first portion (151) of the encapsulation layer (15) may cover the fourth surface (104) of the connecting layer (14), and a second portion (152) of the encapsulation layer (15) may cover the first electrode (21), the second electrode (22), and the fourth region (1034) and fifth region (1035) included in the third surface (103) of the graphene layer (13).

[0068] According to various embodiments, although not separately illustrated, a third edge region (1301) of the graphene layer (13) is reduced and a second portion (152) of the encapsulation layer (15) can be connected to the transfer layer (12) so as to reduce or prevent the graphene layer (13) from being exposed to the side of the planar heating element (1) and so that the graphene layer (13) can be sealed by the transfer layer (12) and the encapsulation layer (15).

[0069] According to various embodiments, the graphene transfer process (a process for transferring graphene) (e.g., CVD process) may have structural defects due to the limitations of consistently achieving homogeneity, reliability, and / or stability for the graphene. When the connecting layer (14) is implemented as an oxidized graphene layer, the structural defects may be included in the double-layer structure (16) of the graphene layer-connecting layer. The structural defects may include defects of the form of voids, openings, slits, or cracks (hereinafter referred to as hole defects (also called hole defect structures) (6)) included in the double-layer structure (16) of the graphene layer-connecting layer. For example, the hole defects (6) having the double-layer structure (16) of the graphene layer-connecting layer may include first hole defects (61) included in the first graphene (131). For example, the hole defect (6) in the double layer structure (16) of the graphene layer-connecting layer may include a second hole defect (62) contained in the second graphene (132). For example, the hole defect (6) in the double layer structure (16) of the graphene layer-connecting layer may include a third hole defect (63) contained in the third graphene (133). For example, the hole defect (6) in the double layer structure (16) of the graphene layer-connecting layer may include a fourth hole defect (64) contained in the graphene oxide layer (e.g., the connecting layer (14). The third hole defect (63) and the fourth hole defect (64) are formed based on the base graphene layer (e.g., the base graphene layer (410) of FIG. 4) during the manufacturing process of the planar heating element (1), and can be understood as an integral hole defect penetrating the third graphene (133) and the graphene oxide layer.

[0070] According to various embodiments, the encapsulation layer (15) may include a third portion (153) disposed (e.g., filled) in a structural defect (e.g., hole defect (6)) of the double layer structure (16) of the graphene layer-linking layer. A process for forming the encapsulation layer (15) may include coating a coating material (e.g., inorganic polysilazane) and then curing (e.g., heat curing), and the third portion (153) may be formed based on a portion of the coating material being filled (e.g., infiltrated or flowed) into the first hole defect (61), the second hole defect (62), the third hole defect (63), and / or the fourth hole defect (64). In various embodiments, the connecting layer (14) may be omitted, and a portion of the third part (153) of the encapsulation layer (15) may be placed (e.g., filled) in the first hole defect (61), the second hole defect (62), and the third hole defect (63) of the graphene layer (13). The encapsulation layer (15) may be stably and firmly bonded to the double layer structure (16) of the graphene layer-connecting layer through the third part (153). The third part (153) of the encapsulation layer (15) may reduce or prevent damage or deformation to the bond between the encapsulation layer (15) and the double layer structure (16) of the graphene layer-connecting layer due to heat and / or external shock generated from the graphene layer (13). The third part (153) of the encapsulation layer (15) can reduce or prevent the deterioration of bonding durability (e.g., interfacial bonding strength and / or interfacial adhesion) of the double layer structure (16) of the encapsulation layer (15) and the graphene layer-connecting layer against high temperatures of, for example, about 500°C or higher and / or external shock. The third part (153) of the encapsulation layer (15) can reduce or prevent the separation of the double layer structure (16) of the encapsulation layer (15) and the graphene layer-connecting layer due to heat and / or external shock.

[0071] According to various embodiments, a third portion (153) of the encapsulation layer (15) may be connected to the transfer layer (12). By the third portion (153) of the encapsulation layer (15), the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer, and the transfer layer (12) may be stably and firmly bonded to each other. The third portion (153) of the encapsulation layer (15) may provide (or form) a mechanical bond (also referred to as a mechanical interaction) (e.g., an anchor effect or anchoring effect or a bridge) between, for example, the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer, and the transfer layer (12). A third portion (153) of the encapsulation layer (15) can provide (or form) an interlocking structure in which the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer, and the transfer layer (12) can be stably and firmly bonded to each other. A third portion (153) of the encapsulation layer (15) can provide (or form) chemical bonding and / or physical bonding to the graphene layer-connecting structure (16) and / or the transfer layer (12). A third portion (153) of the encapsulation layer (15) can reduce or prevent damage or deformation to the bond between the encapsulation layer (15) and the double layer structure (16) of the graphene layer-connecting layer due to heat and / or external shock generated from the graphene layer (13). The third part (153) of the encapsulation layer (15) can reduce or prevent damage or deformation to the bond between the transfer layer (12) and the double layer structure (16) of the graphene layer-connecting layer due to heat and / or external impact generated from the graphene layer (13).The third part (153) of the encapsulation layer (15) can reduce or prevent the deterioration of bonding durability (e.g., interfacial bonding strength and / or interfacial adhesion) for the double layer structure (16) of the encapsulation layer (15) and the graphene layer-connecting layer, and bonding durability (e.g., interfacial bonding strength and / or interfacial adhesion) for the double layer structure (16) of the transfer layer (12) and the graphene layer-connecting layer, for example, against high temperatures of about 500°C or higher and / or external shocks. The third part (153) of the encapsulation layer (15) can reduce or prevent the separation of the double layer structure (16) of the encapsulation layer (15) and the graphene layer-connecting layer due to heat and / or external shocks, and the separation of the double layer structure (16) of the transfer layer (12) and the graphene layer-connecting layer due to heat and / or external shocks.

[0072] According to various embodiments, the graphene layer (13) (or, the double layer structure (16) of the graphene layer-connecting layer) may have a negative coefficient of thermal expansion. The third portion (153) of the encapsulation layer (15) may reduce or prevent the degradation of bonding durability (e.g., interfacial bonding strength and / or interfacial adhesion) between the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer, and the transfer layer (12) due to shrinkage of the graphene layer (13) (or, the double layer structure (16) of the graphene layer-connecting layer) in a high-temperature environment (e.g., high temperature of about 500°C or higher) and / or in an environment where external impact is applied. Due to the third part (153) of the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer and the transfer layer (12) can be improved, and as a result, the performance and / or reliability of the planar heating element (1) can be maintained and / or secured.

[0073] According to various embodiments, if hole defects in the double-layer structure (16) of the graphene layer-connecting layer are located or distributed to a level where it is difficult to ensure the durability of the planar heating element (1), and / or if graphene that is substantially free of hole defects (e.g., defect-free graphene) is formed, the planar heating element (1) may be implemented to have one or more holes (also called openings) (7) formed in the double-layer structure (16) of the graphene layer-connecting layer. One or more holes (7) in the double-layer structure (16) of the graphene layer-connecting layer may be understood as intentionally formed in contrast to structural defects that may unintentionally be present in the double-layer structure (16) of the graphene layer-connecting layer. The encapsulation layer (15) may include a fourth portion disposed (e.g., filled) in one or more holes (7) of the double-layer structure (16) of the graphene layer-connecting layer. One or more holes (7) formed in the double-layer structure (16) of the graphene layer-connecting layer can be understood as through holes penetrating the graphene layer (13) and the transfer layer (12). The graphene layer (13) may include a plurality of first holes (also referred to as first openings) (71), and the connecting layer (14) may include a plurality of formed second holes (also referred to as second openings) (72). One or more holes (7) can be understood as an overlap of the plurality of first holes (71) of the graphene layer (13) and the plurality of second holes (72) of the connecting layer (14). A fourth portion of the encapsulation layer (15) may provide (or form) substantially the same function and / or effect as the third portion (153) which improves the bonding durability between the encapsulation layer (15), the double-layer structure (16) of the graphene layer-connecting layer, and the transfer layer (12).

[0074] According to various embodiments, the connecting layer (14) may be omitted, and one or more holes (7) may be understood as a plurality of first holes (71) of the graphene layer (13).

[0075] According to various embodiments, a first hole defect (61), a second hole defect (62), and a third hole defect (63) included in the graphene layer (13), and / or a plurality of first holes (71) formed in the graphene layer (13) may be understood as a first empty space in which a portion of the encapsulation layer (15) is placed (e.g., filled). A fourth hole defect (64) included in the connection layer (13) and / or a plurality of second holes (72) formed in the connection layer (13) may be understood as a second empty space in which a portion of the encapsulation layer (15) is placed (e.g., filled).

[0076] According to various embodiments, the double layer structure (16) of the graphene layer-linking layer formed through the graphene transfer process (e.g., CVD process) and the oxidation process can be implemented to reduce or prevent other structural defects. Other structural defects may include foreign substances (e.g., dust) that are attached to unwanted material during the graphene transfer process, folding that may occur as the volume of the substrate (11) and / or the transfer layer (12) expands and contracts when the temperature is raised or lowered during the graphene transfer process, and / or stacking in which carbon atoms are stacked in multiple layers during the graphene transfer process, but may be diverse.

[0077] FIG. 4 is a drawing showing a manufacturing flow (manufacturing method) for a planar heating element (1) according to various embodiments of the present disclosure.

[0078] It may be understood in this disclosure that any combination of features and / or embodiments disclosed in connection with FIG. 4 is conceived and included. Any combination of features described below in connection with FIG. 4 may be considered to be included in this disclosure as specific examples.

[0079] Descriptions of some components identical to those in the preceding examples may not be repeated.

[0080] Referring to FIG. 4, a substrate (11) (e.g., a glass substrate) can be formed through a process 401 (also referred to as step 401 or operation 401). The method of forming the substrate (11) can vary. The substrate (11) can be formed, for example, as a thin film that can have flexibility.

[0081] According to various embodiments, a transfer layer (12) disposed (or bonded) on a substrate (11) can be formed through a 402 process (also referred to as step 402 or operation 402). For example, a transfer layer (12) containing silicon dioxide can be formed by coating a coating liquid containing an inorganic polysilazane onto the substrate (11) and then curing (e.g., thermal curing). The coating liquid containing the inorganic polysilazane may, for example, contain about 10% PHPS, but is not limited thereto. Thermal curing may, for example, be performed for about 30 minutes in a temperature environment of about 500°C, but is not limited thereto.

[0082] According to various embodiments, a base graphene layer (410) may be placed (or bonded) to a transfer layer (12) through a process 403 (also referred to as step 403 or operation 403). The base graphene layer (410) may serve as a basis for forming a graphene layer (13) (see FIG. 2 and 3) and an oxidized graphene layer (e.g., a connecting layer (14) in FIG. 2 and 3). For example, the base graphene layer (410) may be formed by growing crystalline graphene by adsorbing and decomposing a carbon precursor in the form of a gas or vapor with high kinetic energy on a second surface (102) of the transfer layer (12) to be grown graphene, thereby decomposing it into carbon atoms and causing the carbon atoms to form interatomic bonds with each other. For example, a method may be utilized in which graphene is transferred (e.g., CVD transfer) onto a transfer substrate formed of a material such as TRT (thermal release tape), PI (polyimide), PET (polyethylene terephthalate), or a wafer, and then the graphene attached to the transfer substrate is transferred (e.g., thermal transfer) to a transfer layer (12). In various embodiments, the method of placing the base graphene layer (410) on the transfer layer (12) (e.g., graphene transfer method) may vary in other ways.

[0083] According to various embodiments, a graphene oxide layer (420) (e.g., a connecting layer (14)) may be formed through a process 404 (also referred to as step 404 or operation 404). A first masking member (431) and a second masking member (432) may be disposed on the base graphene layer (410). The first masking member (431) may be disposed in the area of ​​the base graphene layer (410) where the first electrode (21) is disposed. The second masking member (432) may be disposed in the area of ​​the base graphene layer (410) where the second electrode (22) is disposed. Through an oxidation process, the surface of the base graphene layer (410) may be oxidized to form a double layer structure (e.g., the double layer structure (16) of FIG. 2 and 3) comprising a graphene layer (13) and a graphene oxide layer (420). The first masking member (431) can prevent graphene oxide from being formed in the area of ​​the base graphene layer (410) where the first electrode (21) is placed. The second masking member (432) can prevent graphene oxide from being formed in the area of ​​the base graphene layer (410) where the second electrode (22) is placed. The oxidation process can be carried out, for example, through a surface treatment device (e.g., a UV ozone cleaner) using light having a specified wavelength (e.g., UV) (440). The oxidation process may include, for example, applying UV having a wavelength of about 245 nm for about 60 minutes. The oxidation process is not limited thereto.

[0084] According to various embodiments, through process 405 (also referred to as step 405 or operation 405), the first masking member (431) and the second masking member (432) are separated, and then the first electrode (21) and the second electrode (22) can be placed (or bonded) to the graphene layer (13). The first electrode (21) and the second electrode (22) can be formed, for example, through screen printing. For example, the first electrode (21) and the second electrode (22) placed (or bonded) to the graphene layer (13) can be formed by high-temperature firing of a metal paste (e.g., silver paste (Ag paste)) containing about 3 to about 5% glass powder (e.g., glass frit) at a temperature of about 500°C for about 30 minutes. The method of forming the first electrode (21) and the second electrode (22) may not be limited thereto. The first electrode (21) and / or the second electrode (22) may be formed with a thickness of about 20 μm, but is not limited thereto.

[0085] According to various embodiments, through a 406 process (also referred to as step 406 or operation 406) (e.g., encapsulation), an encapsulation layer (15) may be formed to reduce or prevent external environmental factors, such as air or moisture, from penetrating into the graphene layer (13). The encapsulation layer (15) may be formed, for example, by coating (e.g., spray coating) and then curing (e.g., heat curing) an inorganic polysilazane, so that the inorganic polysilazane reacts with moisture or oxygen to form an encapsulation layer (15) of the silicon dioxide layer. The coating liquid containing the inorganic polysilazane may, for example, contain about 10% PHPS. Heat curing may be performed for about 30 minutes in a temperature environment of about 500°C.

[0086] According to various embodiments, through the 406 process, the encapsulation layer (15) may include a third portion (153) (see FIG. 2 and 3) disposed (e.g., filled) in a hole defect (e.g., first hole defect (61), second hole defect (62), third hole defect (63), and fourth hole defect (64)) of a double layer structure (e.g., double layer structure (16) of FIG. 2 and 3) comprising a graphene layer (13) and a graphene oxide layer (420). The third portion (153) of the encapsulation layer (15) (see FIG. 2 and 3) may be connected to a transfer layer (12). By means of the third part (153) of the encapsulation layer (15) (see FIG. 2 and 3), the encapsulation layer (15), the double layer structure (e.g., the double layer structure (16) of FIG. 2 and 3) including the graphene layer (13) and the graphene oxide layer (420), and the transfer layer (12) can be stably and firmly bonded to each other.

[0087] According to various embodiments, if a hole defect (6) (see FIG. 2 and 3) having a double layer structure (e.g., double layer structure (16) of FIG. 2 and 3) comprising a graphene layer (13) and a graphene oxide layer (420) is located or distributed at a level where it is difficult to ensure the durability of the planar heating element (1), and / or if a base graphene layer (410) (e.g., a defect-free graphene layer) is formed that substantially does not contain a hole defect, a process (or operation) of additionally forming one or more holes (e.g., one or more holes (7) of FIG. 2 and 3 or a plurality of holes (8) of FIG. 8) in a double layer structure comprising a graphene layer (13) and a graphene oxide layer (420) may be performed between the fifth process (405) and the sixth process (406). One or more holes may be formed in the double layer structure comprising a graphene layer (13) and a graphene oxide layer (420), for example, through a laser. The laser may have a pulse width of less than or equal to a set or specified value (e.g., the time interval during which the amplitude is substantially halved in the rise and fall times of the pulse). When a portion of a double-layer structure including a graphene layer (13) and a graphene oxide layer (420) is removed using a laser having a pulse width of less than or equal to a set or specified value, the occurrence of burrs can be reduced. Burrs may be, for example, residues remaining in a protruding form around the removed portion. A laser having a pulse width of less than or equal to a set or specified value may have a shorter thermal propagation time than that of a double-layer structure including a graphene layer (13) and a graphene oxide layer (420), thereby reducing thermal damage or structural changes to a double-layer structure including a graphene layer (13) and a graphene oxide layer (420), which in turn reduces thermal diffusion phenomena and thus reduces the occurrence of burrs. A laser having a pulse width of less than or equal to a set or specified value may have a pulse width of, for example, a nanosecond (10 -9A nanosecond laser having a pulse width of (second) or femtosecond (10 -15 A femtosecond laser with a pulse width of (seconds) may be included. A laser having a pulse width less than or equal to a set or specified value may be an excimer laser. The laser may be configured to deliver thermal energy to a specific depth (e.g., a femtosecond laser) or configured to deliver thermal energy to a specific depth (e.g., an excimer laser) so as to reduce or prevent damage to the transfer layer (12). Through the sixth process (406), the encapsulation layer (15) may include a fourth portion located in one or more holes (e.g., one or more holes (7) in FIGS. 2 and 3 or a plurality of holes (8) in FIGS. 8) of a double layer structure (e.g., double layer structure (16) of FIGS. 2 and 3) comprising a graphene layer (13) and a graphene oxide layer (420). The fourth portion of the encapsulation layer (15) can improve the bonding durability between the encapsulation layer (15), the graphene layer (13), the graphene oxide layer (420), and the transfer layer (12). One or more holes (e.g., one or more holes (7) in FIG. 2 and 3 or a plurality of holes (8) in FIG. 8) can be formed through various processing tools without being restricted by a laser.

[0088] According to various embodiments, when the connecting layer (14) is omitted, the process of forming holes (e.g., one or more holes (7) in FIG. 2 and 3 or a plurality of holes (8) in FIG. 8) can be understood as forming one or more holes (e.g., a plurality of first holes (71) in FIG. 2 and 3) in the graphene layer (13).

[0089] FIG. 5 is a graph showing the temperature generated from a planar heating element of a comparative example and a planar heating element (1) of the present disclosure with respect to an applied voltage according to various embodiments of the present disclosure.

[0090] Referring to FIG. 5, 51 is a graph showing voltage and heating temperature for a planar heating element of a comparative example. The planar heating element of the comparative example may, for example, have a graphene layer (e.g., a graphene layer (13) of FIG. 2 and 3) placed (or bonded) on a substrate (e.g., a substrate (11) of FIG. 2 and 3). The planar heating element of the comparative example generates heat of up to about 350°C, and when a voltage of about 150V (volt) or higher is applied, the temperature does not rise further, and the electrodes are carbonized or the graphene layer is damaged (e.g., cracked), resulting in deterioration or loss of heating performance (see 511). In the planar heating element of the comparative example, the graphene layer is oxidized and lost in a high-temperature environment of about 350°C or higher, and as a result, the heating performance may deteriorate due to the difference between the resistance of the planar heating element (or graphene layer) before heating and the resistance of the planar heating element (or graphene layer) after heating.

[0091] According to various embodiments, 52 is a graph showing voltage and heating temperature for the planar heating element (1) of the present disclosure. 521 shows voltage and heating temperature during a first heating measurement for the planar heating element (1) of the present disclosure. 522 shows voltage and heating temperature during a second heating measurement for the planar heating element (1) of the present disclosure. The planar heating element (1) of the present disclosure can reduce heating deviation as in 521 and 522 because it can reduce or prevent loss of the planar heating element (1) due to improved structural stability compared to the planar heating element of the comparative example. The planar heating element (1) of the present disclosure can form uniform planar heating of up to about 500°C while reducing or preventing loss of the planar heating element (1) due to improved structural stability compared to the planar heating element of the comparative example.

[0092] FIG. 6 is a diagram showing the dispersion of surface resistance by region of a comparative example planar heating element according to various embodiments.

[0093] For the commercialization and / or mass production of planar heating elements, standardization may be required to evaluate the quality of the graphene layer (e.g., the graphene layer (13) in FIG. 2 and 3) (or, a method for manufacturing a graphene layer with a quality capable of reducing defects) as well as the electrical characteristics as a heating element. For example, to evaluate the quality of the graphene layer, measurement factors such as contact sheet resistance, eddy current-based non-contact sheet resistance, surface enhanced Raman spectroscopy (SERS), or electrode-to-electrode resistance may be used as a standard. In various embodiments, planar heating elements may be mass-produced based on area-specific sheet resistance and / or heating element resistance that can be measured immediately during the manufacturing process. Area-specific sheet resistance (referred to as surface resistance) for a planar heating element can be understood as the total resistance of a unit area of ​​a plate-like structure having a reference length and reference width in the graphene layer (e.g., a unit area of ​​a square or rectangular plate-like structure). The heating element resistance of a planar heating element can be understood as the total resistance of the graphene layer between the first electrode (e.g., the first electrode (21) in FIG. 3) and the second electrode (e.g., the second electrode (22) in FIG. 3). Due to physical, chemical, and / or structural non-uniformity in the manufacturing process of the graphene layer, the quality of the graphene layer may vary by region of the planar heating element, which can cause a large dispersion of the sheet resistance (also called sheet resistance per unit area) of the planar heating element (e.g., the degree or magnitude of the sheet resistance spreading out from the target resistance). For example, referring to FIG. 6, different colors are displayed according to the resistance size, showing that the dispersion of the sheet resistance by region is large in the planar heating element of the comparison example. Large dispersion of surface resistance by region in a planar heating element can cause deviations in the resistance of the planar heating elements, requiring different power to be applied to each planar heating element to achieve the desired (or designed) surface heating or heating temperature, which can make commercialization and / or mass production difficult.Accordingly, in order to commercialize and / or mass-produce planar heating elements, it is necessary to reduce the dispersion of surface resistance by region of the planar heating element. The present disclosure will describe, with reference to FIGS. 7, 8, and 9, a means or method for solving or at least mitigating the problem of dispersion of surface resistance by region of the planar heating element of the comparative example. Reducing the dispersion of surface resistance by region of the planar heating element can be understood as reducing the deviation between the surface resistances of multiple regions and enabling the surface resistances of multiple regions to have substantially the same target resistance or to be as close as possible to the target resistance. The planar heating element of the present disclosure can be understood as solving or at least mitigating the aforementioned problem of the planar heating element of the comparative example.

[0094] FIG. 7 is a graph showing the correlation between the surface resistance and heating element resistance of comparative examples of planar heating elements according to various embodiments.

[0095] Referring to FIG. 7, 701 is a graph showing the correlation between region-specific sheet resistance and heating element resistance in comparative example planar heating elements in which the graphene layer is formed as a single layer of graphene. 702 is a graph showing the correlation between region-specific sheet resistance and heating element resistance in comparative example planar heating elements in which the graphene layer is formed as double layers of graphene. Referring to 701 and 702, the region-specific sheet resistance and heating element resistance in the comparative example planar heating elements show a substantially positive linear relationship, and it appears that if the problem of the dispersion of region-specific sheet resistance can be resolved or at least mitigated, the deviation in the heating element resistance of the planar heating elements can be reduced, thereby enabling the commercialization and / or mass production of planar heating elements.

[0096] FIG. 8 is a drawing showing a planar heating element (1) according to various embodiments of the present disclosure.

[0097] It may be understood in this disclosure that any combination of features and / or embodiments disclosed in connection with FIG. 8 is conceived and included. Any combination of features described below in connection with FIG. 8 may be considered to be included in this disclosure as specific examples.

[0098] Referring to FIG. 8, the planar heating element (1) may include a plurality of holes (8) (e.g., one or more holes (7) in FIG. 2 and 3). The plurality of holes (8) may be formed in a double-layer structure (16) of a graphene layer-connecting layer (see FIG. 2 and 3). The plurality of holes (8) may be understood as a superposition of a plurality of first holes (71) formed in the graphene layer (13) and a plurality of second holes (72) formed in the connecting layer (14). In various embodiments, where the connecting layer (14) (see FIG. 2 and 3) is omitted, the plurality of holes (8) may be understood as one or more holes formed in the graphene layer (13) (e.g., a plurality of first holes (71) in FIG. 2 and 3). A plurality of holes (8) can be understood as a portion of a lattice structure (e.g., honeycomb structure or honeycomb lattice) in which carbon atoms are located at the vertices of a hexagon, which has been removed. A plurality of holes (8) can be formed in the double-layer structure (16) of the graphene layer-connecting layer (see FIG. 2 and 3), for example, through a laser, but is not limited thereto. The laser can be, for example, a nanosecond laser, a femtosecond laser, or an excimer laser. For example, the plurality of holes (8) may include nanoholes or femtoholes. A plurality of holes (8) can be understood as holes having a radius through which the laser can penetrate a target object.

[0099] According to various embodiments, when viewed from above on the fifth surface (105) of the bag layer (15) (see FIG. 2 and 3), any two of the plurality of holes (8) may have substantially the same radius. In various embodiments, any two of the plurality of holes (8) may have different radii. In various embodiments, when viewed from above on the fifth surface (105) of the bag layer (15) (see FIG. 2 and 3), the distance between any two adjacent holes among the plurality of holes (8) (e.g., the distance between the centers of the holes) may be substantially the same or different from the distance between any two adjacent holes among the plurality of holes (8).

[0100] According to various embodiments, a plurality of holes (8) may have substantially the same diameter (D) and may be formed as a hole array in a square grid pattern. The plurality of holes (8) may be arranged, for example, at a first distance (S1) between the hole centers in a first direction (e.g., a direction parallel to the x-axis) and at a second distance (S2) between the hole centers in a second direction perpendicular to the first direction (e.g., a direction parallel to the y-axis). The first distance (S1) and the second distance (S2) may be substantially the same or different from each other.

[0101] According to various embodiments, although not separately illustrated, a plurality of holes (8) are not restricted to a square grid pattern and can form a hole array arranged in a different pattern.

[0102] According to various embodiments, when viewed from above on the fifth side (105) of the bag layer (15) (see FIG. 2 and 3), the shape, size, number, and / or arrangement of the plurality of holes (8) may vary and are not limited to the illustrated example. The plurality of holes (8) may be, for example, slits (e.g., thin and narrow holes). The arrangement of the plurality of holes (8) may be understood as the relative position between any two adjacent holes. In the illustrated example, the plurality of holes (8) appear to be formed in a regular arrangement (e.g., a square grid pattern), but are not limited thereto.

[0103] According to various embodiments, the encapsulation layer (15) (see FIG. 2 and 3) may include a fourth portion disposed (e.g., filled) in a plurality of holes (8). The encapsulation layer (15) may be connected to the transfer layer (12) (see FIG. 2 and 3) through the fourth portion. The fourth portion of the encapsulation layer (15) may improve the bonding durability (e.g., interfacial bonding strength and / or interfacial adhesion) between the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer (see FIG. 2 and 3), and the transfer layer (12) against heat and / or external shock. The fourth portion of the encapsulation layer (15) may provide (or form) substantially the same function and / or effect as the third portion (153) (see FIG. 2 and 3) improves the bonding durability between the encapsulation layer (15), the double layer structure (16) of the graphene layer-connecting layer, and the transfer layer (12).

[0104] According to various embodiments, the shape, size, number, and / or arrangement of a plurality of holes (8) may be determined in order to reduce the variation in surface resistance of a planar heating element (1) by region, that is, to reduce the variation between surface resistances of a plurality of regions (e.g., unit regions) and to enable the surface resistances of the plurality of regions to have substantially the same target resistance or to be as close as possible to the target resistance. Reducing the variation between surface resistances of a plurality of regions (e.g., unit regions) of a planar heating element (1) and enabling the surface resistances of the plurality of regions to have substantially the same target resistance or to be as close as possible to the target resistance can be understood as reducing the variation in heating element resistance of a plurality of planar heating elements produced in mass.

[0105] In order to reduce the variation in heating element resistance of multiple planar heating elements during the process of manufacturing planar heating elements, I will describe by example the determination of the effective area ratio (e.g., porosity) to be removed by hole processing in the graphene layer (13) (see FIGS. 2 and 3) when the double layer structure (16) (see FIGS. 2 and 3) of the graphene layer-connecting layer (14) (see FIGS. 2 and 3) is omitted. During the process of manufacturing planar heating elements, it may be confirmed that the heating element resistance of the first planar heating element is about 80 Ω (ohm) and the heating element resistance of the second planar heating element is about 100 Ω (ohm). For commercialization and / or mass production of the planar heating elements, the target resistance for the heating element resistance may be set to about 120 Ω. Based on a ratio of about 80Ω to about 120Ω, it is determined for the first planar heating element that about 33% of the total area of ​​the graphene layer (13) (see FIG. 2 and 3) must be removed through a plurality of holes (e.g., a plurality of holes (8) in FIG. 8) when the double layer structure (16) (see FIG. 2 and 3) of the graphene layer-connecting layer, or the connecting layer (14) (see FIG. 2 and 3) is omitted, and the process of forming the plurality of holes can be carried out between the fifth process (405) (see FIG. 4) and the sixth process (406) (see FIG. 4). Based on a ratio of about 100Ω to about 120Ω, it is determined for the second planar heating element that about 16.7% of the total area of ​​the graphene layer (13) (see FIG. 2 and 3) must be removed through a plurality of holes (e.g., a plurality of holes (8) in FIG. 8) when the double layer structure (16) (see FIG. 2 and 3) of the graphene layer-connecting layer, or the connecting layer (14) (see FIG. 3) is omitted, and the process of forming the plurality of holes can be carried out between the fifth process (405) (see FIG. 4) and the sixth process (406) (see FIG. 4).The process of forming multiple holes can be assumed to form multiple holes having substantially the same diameter into a hole array in the shape of a square grid (see FIG. 8). In the process of forming multiple holes, it can be determined that the number of multiple holes in the hole array for the first planar heating element is greater than the number of multiple holes in the hole array for the second planar heating element. In the process of forming multiple holes, it can be determined that the spacing between the multiple holes in the hole array for the second planar heating element is greater than the spacing between the multiple holes in the hole array for the first planar heating element. For example, assuming that the multiple holes in the hole array have a diameter of about 500 nm, in the process of forming multiple holes, it can be determined that the multiple holes in the hole array for the first planar heating element are arranged at a spacing of about 1 μm, and the multiple holes in the hole array for the second planar heating element are arranged at a spacing of about 2 μm.

[0106] According to various embodiments, design criteria for a process of forming multiple holes to reduce variations in heating element resistance among multiple planar heating elements during the manufacturing process of planar heating elements can be accumulated as data as the number of process iterations increases. The accumulated data may indicate an optimized relationship between surface resistance and heating element resistance by region. The accumulated data can be utilized to reduce variations in heating element resistance among multiple planar heating elements. Design criteria for a process of forming multiple holes may include, for example, the shape, size, number, and / or arrangement of the multiple holes. Design criteria for a process of forming multiple holes may include data regarding the hole processing method. There may be various other design criteria for a process of forming multiple holes.

[0107] According to various embodiments, the process of forming multiple holes to reduce the variation in heating element resistance of multiple planar heating elements during the process of manufacturing planar heating elements may be configured to utilize a generative AI system. For example, the generative AI system may include a trained machine learning model. In various embodiments, the shape and / or size of the planar heating element or graphene layer to be manufactured, defect data analyzed for the graphene layer (e.g., resistance per unit area), the shape and / or size of the unit area for sheet resistance, data on sheet resistance per area, the shape, size, number, and / or arrangement of multiple holes for hole processing, the heating element resistance of the planar heating element measured during the process of manufacturing the planar heating element, the target resistance for the heating element resistance, data on transparency per area, the target transparency of the planar heating element, various data related to the hole processing method, and other various parameters during the manufacturing process regarding the planar heating element (e.g., manufacturing environment such as temperature and pressure) may be utilized as training data for the generative AI system. The process of forming multiple holes can be configured to recognize or predict states or information related to the process of manufacturing a planar heating element through a generative AI system. The process of manufacturing a planar heating element can be configured to control the process of forming multiple holes based on the states or information recognized or predicted through the generative AI system.

[0108] According to various embodiments, a plurality of holes formed to reduce variation in the heating element resistance of a plurality of planar heating elements can be implemented to reduce the influence on the transparency (e.g., target transparency) of the plurality of planar heating elements. The plurality of planar heating elements can be implemented such that the plurality of holes are concentrated in at least one area (e.g., unit area) to reduce variation in transparency per area.

[0109] According to various embodiments, in the case where the double layer structure (16) (see FIG. 2 and 3) of the graphene layer-connecting layer implemented to include a plurality of holes according to the present disclosure, or the connecting layer (14) (see FIG. 2 and 3) is omitted, the graphene layer (13) (see FIG. 2 and 3) is manufactured so that the heating element resistance is controlled at a level where transmittance and heating performance are secured while maintaining the shape and / or size of the heating area of ​​the planar heating element, thereby reducing the variation between the heating element resistances of a plurality of planar heating elements that may occur during the process of forming the graphene layer.

[0110] FIG. 9 is a graph showing the variation in heating element resistance between planar heating elements of comparative examples according to various embodiments of the present disclosure and the variation in heating element resistance between planar heating elements of the present disclosure.

[0111] Referring to FIG. 9, 901 represents a variation in heating element resistance between planar heating elements of a comparative example. 902 represents a variation in heating element resistance between planar heating elements of the present disclosure. Planar heating elements of a comparative example may not include a plurality of holes to reduce the variation in heating element resistance and appear to be substantially difficult to commercialize and / or mass-produce compared to planar heating elements of the present disclosure. Planar heating elements of the present disclosure may be implemented to relatively further reduce the variation in heating element resistance through a plurality of holes (e.g., a plurality of holes (8) in FIG. 8) compared to planar heating elements of a comparative example, thereby enabling commercialization and / or mass production.

[0112] According to various embodiments of the present disclosure, a planar heating element (e.g., planar heating element (1)) comprises a substrate (e.g., substrate (11)), a transfer layer on the substrate (e.g., transfer layer (12)), a graphene layer on the transfer layer (e.g., graphene layer (13)), an encapsulation layer configured to seal the graphene layer (e.g., encapsulation layer (15)), and a connecting layer between the graphene layer and the encapsulation layer configured to connect the graphene layer and the encapsulation layer (e.g., connecting layer (14)). The graphene layer and the connecting layer comprise a void space (e.g., structural defect (6) and / or one or more holes (7)) configured to be filled by the encapsulation layer to connect the transfer layer and the encapsulation layer.

[0113] According to various embodiments of the present disclosure, the connecting layer (e.g., connecting layer (14)) may include a graphene oxide layer. The void may include structural defects (e.g., a first hole defect (61), a second hole defect (62), a third hole defect (63), and / or a fourth hole defect (64)) contained in the graphene layer (e.g., graphene layer (13)) and the graphene oxide layer (e.g., graphene oxide layer (420)).

[0114] According to various embodiments of the present disclosure, the empty space may include one or more holes (e.g., one or more holes (7)) formed in a graphene layer (e.g., graphene layer (13)) and a connecting layer (e.g., connecting layer (14)) through a processing tool.

[0115] According to various embodiments of the present disclosure, one or more holes (e.g., one or more holes (7)) may be formed based on the resistance of a planar heating element (e.g., planar heating element (1)).

[0116] According to various embodiments of the present disclosure, the connecting layer (e.g., connecting layer (14)) may include graphene oxide.

[0117] According to various embodiments of the present disclosure, the transfer layer (e.g., transfer layer (12)) and the encapsulation layer (e.g., encapsulation layer (15)) may comprise silicon dioxide formed based on an inorganic polysilazane.

[0118] According to various embodiments of the present disclosure, a method for manufacturing a planar heating element (e.g., planar heating element (1)) comprises the steps of forming a substrate (e.g., substrate (11)), forming a transfer layer (e.g., transfer layer (12)) on the substrate, forming a graphene layer (e.g., graphene layer (13)) on the transfer layer, forming a connection layer (e.g., connection layer (14)) on the graphene layer, and forming an encapsulation layer (e.g., encapsulation layer (15)) configured to seal the graphene layer. The connection layer is configured to connect the graphene layer and the encapsulation layer. The graphene layer and the connection layer include empty spaces (e.g., structural defects (6) and / or one or more holes (7)) configured to be filled by the encapsulation layer so as to connect the transfer layer and the encapsulation layer.

[0119] According to various embodiments of the present disclosure, in a method for manufacturing a planar heating element (e.g., planar heating element (1)), a connecting layer (e.g., connecting layer (14)) may include a graphene oxide layer. The void space may include a graphene layer (e.g., graphene layer (13)) and a structural defect (e.g., a first hole defect (61), a second hole defect (62), a third hole defect, and / or a fourth hole defect (64)) contained in the graphene oxide layer.

[0120] According to various embodiments of the present disclosure, in a method for manufacturing a planar heating element (e.g., planar heating element (1)), the empty space may include one or more holes (e.g., one or more holes (7)) formed in a graphene layer (e.g., graphene layer (13)) and a connecting layer (e.g., connecting layer (14)) through a processing tool.

[0121] According to various embodiments of the present disclosure, in a method for manufacturing a planar heating element (e.g., planar heating element (1)), one or more holes (e.g., one or more holes (7)) may be formed based on the resistance of the planar heating element.

[0122] According to various embodiments of the present disclosure, in a method for manufacturing a planar heating element (e.g., planar heating element (1)), a connecting layer (e.g., connecting layer (14)) may include graphene oxide.

[0123] According to various embodiments of the present disclosure, in a method for manufacturing a planar heating element (e.g., planar heating element (1)), a transfer layer (e.g., transfer layer (12)) and a sealing layer (e.g., sealing layer (15)) may comprise silicon dioxide formed based on an inorganic polysilazane.

[0124] The embodiments disclosed in this disclosure and the drawings are provided merely as examples to facilitate the explanation of the technical content and to aid in understanding this disclosure, and are not intended to limit the scope of this disclosure. Accordingly, it should be understood that the scope of the various embodiments of this disclosure includes modifications or variations other than those disclosed herein. Additionally, it will be understood that any embodiment(s) described herein may be used in conjunction with any other embodiment(s) described herein. For example, this disclosure is presented in the form of providing multiple embodiments each defining a number of features, but it is emphasized that some of these embodiments are connected only by reference to the same drawings or drawings. This disclosure should be understood to include all combinations of these embodiments, unless there is an obvious contradiction between two (or more) embodiments. For example, where features are presented as optional in this disclosure, all combinations of such optional features are included in this disclosure.

Claims

1. In a planar heating element (1), substrate (11); A transfer layer (12) on the above substrate (11); A graphene layer (13) on the above transfer layer (12); A sealing layer (15) configured to seal the graphene layer (13); and It includes a connecting layer (14) between the graphene layer (13) and the encapsulation layer (15), configured to connect the graphene layer (13) and the encapsulation layer (15), and A planar heating element comprising a graphene layer (13) and a connecting layer (14), the above graphene layer (13) and the above connecting layer (14) having a void space (6, 7) configured to be filled with the sealing layer (15) so as to connect the transfer layer (12) and the sealing layer (15).

2. In Paragraph 1, The above connecting layer (14) includes a graphene oxide layer, and The above empty space is a planar heating element comprising structural defects (61, 62, 63, 64) included in the graphene layer (13) and the graphene oxide layer.

3. In Paragraph 1, The above empty space comprises one or more holes (7) formed in the graphene layer (13) and the connecting layer (14) through a processing tool, a planar heating element.

4. In Paragraph 3, The above one or more holes (7) are a planar heating element formed based on the resistance of the planar heating element (1).

5. In Paragraph 1, The above connecting layer (14) is a planar heating element comprising graphene oxide.

6. In Paragraph 1, The above transfer layer (12) and the above encapsulation layer (15) are planar heating elements comprising silicon dioxide formed based on inorganic polysilazane.

7. In a method for manufacturing a planar heating element (1), Step of forming a substrate (11): A step of forming a transfer layer (12) on the substrate (11); A step of forming a graphene layer (13) on the above transfer layer (12); A step of forming a connecting layer (14) on the graphene layer (13); and The method includes the step of forming a sealing layer (15) configured to seal the graphene layer (13), and The above connecting layer (14) is configured to connect the graphene layer (13) and the encapsulation layer (15), and A method comprising the above graphene layer (13) and the above connecting layer (14) including empty spaces (6, 7) configured to be filled with the encapsulation layer (15) so as to connect the above transfer layer (12) and the above encapsulation layer (15).

8. In Paragraph 7, The above connecting layer (14) includes a graphene oxide layer, and A method in which the above empty space includes structural defects (61, 62, 63, 64) included in the graphene layer (13) and the graphene oxide layer.

9. In Paragraph 7, A method in which the above empty space comprises one or more holes (7) formed in the graphene layer (13) and the connecting layer (14) through a processing tool.

10. In Paragraph 9, The above one or more holes (7) are formed based on the resistance of the planar heating element (1), in a method.

11. In Paragraph 7, The above connecting layer (14) comprises graphene oxide, method.

12. In Paragraph 7, A method in which the transfer layer (12) and the encapsulation layer (15) comprise silicon dioxide formed based on inorganic polysilazane.

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