Substrate with graphene oxide layer intended for layer transfer by laser separation and method of manufacture

Abstract

The invention comprises a starting structure (Struct_0) designed to be separated by laser irradiation, said starting structure comprising a substrate (Sub2), a transfer layer (TrLay) and a graphene oxide layer (GO, GO2) interposed between said substrate (Sub2) and said transfer layer (TrLay).

Description

Technical Field

[0001] The present invention relates to a support for manufacturing products in the semiconductor field, the support having one or more layers to be transferred and intended to be separated from at least a portion of the support by laser irradiation at a separation layer included in the support. Background Technology

[0002] The semiconductor industry is increasingly using thin-layer transfer technology, which involves forming a thin layer on a first substrate in a first step and then transferring the formed thin layer to a second substrate in a second step.

[0003] The first substrate may be selected because of its compatibility with the conditions for forming the thin layer, or the thin layer may be formed in the material body forming the first substrate.

[0004] The second substrate is suitable for utilizing the thin layer, for example, through compatibility with subsequent manufacturing steps, or even by supporting the structure in which the thin layer will be integrated.

[0005] Among the thin-layer transfer technologies used in the semiconductor industry, laser-based separation (laser lift-off – LLO) has been found to be an effective method for separating a film or a stack of multiple films or one or more thin layers from a supporting substrate using a layer called a separation layer, the separation or degradation of which is triggered by a laser.

[0006] Typically, the separation layer is irradiated by a laser through a supporting substrate. The separation layer must absorb sufficient light at the laser wavelength to aid separation or its degradation (e.g., by locally melting the separation layer or dissociating it into its basic components), while the supporting substrate must be substantially transparent at that wavelength. A balance must be struck between the laser power, laser wavelength, and materials (for both the separation layer and the supporting substrate) to allow separation while protecting the one or more layers to be transferred from energy dissipation caused by light-interaction processes: heat transfer due to absorption in the separation layer, or direct absorption of partial laser irradiation by the one or more layers to be transferred.

[0007] US Patent 11,069,865 B2 describes a method for manufacturing a flexible OLED display panel, wherein the display panel is manufactured on a glass plate covered with an organic release layer that strongly absorbs ultraviolet radiation. The display panel is detached from the glass plate by a laser separation operation, wherein the release layer capable of absorbing ultraviolet radiation is irradiated through the glass plate by a laser operating in the ultraviolet domain, thereby promoting separation.

[0008] The number of candidate materials available for use as separation layers is limited, and even more so when considering contamination specifications in semiconductor device fabrication methods, particularly during front-end operations. One of the most commonly used materials is gallium nitride (GaN), which constitutes an advantageous solution for LLO (Limited-Low Logging) via UV irradiation (referred to as UV-LLO), as described in U.S. Patent 8,598,014 B2.

[0009] However, the use of GaN on production lines is often associated with contamination in both the front and back ends of the line. Furthermore, UV-LLO associated with GaN requires a thick GaN layer, a portion of which is ablated by the laser for LLO, while the remainder is adversely affected by the elevated temperatures caused by laser irradiation. LLO using UV is also cumbersome, requiring sophisticated laser equipment and posing energy-related risks to both the sample and the operator.

[0010] Reference KR 20240027262 A1 describes a method for laser ablation by irradiating graphene, graphene oxide, or reduced graphene oxide layers.

[0011] Document CN 117238747 A describes a method for laser exfoliation using an exfoliation layer formed from graphene oxide obtained by liquid phase deposition. Summary of the Invention

[0012] One subject of this invention is to solve the aforementioned problems by using a graphene oxide layer as a light-absorbing layer in a layer separation method via laser irradiation (LLO). More specifically, this invention relates to a structure capable of withstanding laser irradiation separation and a method for manufacturing the structure.

[0013] Another subject of the present invention is a method for manufacturing advanced structures based on the structure obtained by the method of the first subject of the present invention.

[0014] To implement these objectives, a first aspect of the invention is a starting structure designed to withstand laser irradiation separation, the starting structure comprising a substrate, a transfer layer, and a graphene oxide layer interposed between the substrate and the transfer layer. The transfer layer may be composed of single-crystal silicon carbide (SiC) or sapphire.

[0015] The structure according to the invention enables the provision of a structure ready for integration into a method for manufacturing a semiconductor device that requires the transfer of a layer from a first support to a second support. Therefore, the starting structure or substrate for an integrated manufacturing method of a semiconductor substrate device can be referred to as “epitaxically ready” because the structure or substrate is ready to be used as a support for growing a layer via epitaxy. More generally, the layer can withstand any manufacturing step conventionally used in the semiconductor industry, such as photolithography, thermal processing, or plasma processing, or the deposition of conductive, insulating, or semiconductor material layers.

[0016] One advantage of the structure according to the invention is that it provides an alternative to existing solutions that may result in undesirable contamination of devices manufactured using the structure.

[0017] Another advantage is the level of infrared light absorption by the graphene oxide layer. During separation operations via laser irradiation, if the radiation has a suitable wavelength, the energy of the incident radiation will be substantially absorbed by the graphene layer, thus limiting the thermal degradation of the rest of the structure, particularly the layers transferred to the second support. Therefore, it is not necessary to maximize the thickness of the graphene layer to absorb as much laser irradiation as possible and avoid its absorption by other layers (which may subsequently degrade), which may be transparent to infrared radiation.

[0018] An additional advantage is the graphene oxide layer's tolerance to typical high temperatures, such as those typically achieved through epitaxial deposition methods performed between 800°C and 1500°C. For this additional reason, the structure according to the invention is compatible with a wide range of methods that may be applied thereto in the semiconductor field.

[0019] Additional non-limiting features of the first aspect of the invention, considered individually or in any technically feasible combination: - The substrate can be transparent to infrared radiation; - The substrate can be transparent to radiation with wavelengths between 9 µm and 11 µm; - The substrate can be made of silicon (Si) or silicon carbide (SiC); and - The transfer layer can be made of single-crystal silicon carbide (SiC) or sapphire.

[0020] A second aspect of the invention is a method for manufacturing a starting structure designed to be separated by laser irradiation, the starting structure comprising a substrate, a transfer layer, and a graphene oxide layer interposed between the substrate and the transfer layer, the method comprising: providing two substrates; forming at least one multilayer graphene layer on at least one of the two substrates; oxidizing the at least one multilayer graphene layer to form at least one graphene oxide layer; bonding the two substrates via the at least one graphene oxide layer; and detaching a portion of one of the two substrates to leave the transfer layer on the other of the two substrates.

[0021] Additional non-limiting features of the second aspect of the invention, considered individually or in any technically feasible combination: - The joining process can be performed through direct contact; - Multiple layers of graphene can be formed on each of the two substrates; and - The method may further include the step of performing ion implantation in a first substrate to form a weakening plane in the first substrate thereby defining a transfer layer; and - The transfer layer can be made of single-crystal silicon carbide (SiC) or sapphire.

[0022] A third aspect of the invention is a method for manufacturing an advanced structure comprising a layer epitaxially formed on a transfer layer of a starting structure, the starting structure being designed to be separated by laser irradiation, the starting structure comprising a substrate, a transfer layer, and a graphene oxide layer interposed between the substrate and the transfer layer, the method comprising the steps of: providing a starting structure according to a first aspect of the invention; epitaxially forming the layer on the transfer layer of the provided structure; bonding the third substrate to the structure by directly contacting the epitaxial layer with the third substrate; and irradiating the graphene oxide layer by infrared irradiation to separate the transfer layer, the epitaxial layer, and the third substrate from the substrate of the starting structure.

[0023] Additional non-limiting features of the third aspect of the invention, considered individually or in any technically feasible combination: - Irradiation uses electromagnetic waves with wavelengths between 9 µm and 11 µm; - The method may also include a step of removing the layer after the separation step; and - The epitaxial layer is a gallium nitride (GaN) layer; and - The transfer layer can be made of single-crystal silicon carbide (SiC) or sapphire.

[0024] One advantage of these methods is their simplicity and their superior technical benefits relative to cost.

[0025] Another advantage of the method according to the invention stems from the ease of use of laser irradiation in the infrared domain, combined with the use of materials compatible with methods for manufacturing semiconductor devices. Attached Figure Description

[0026] Other features and advantages of the invention will become apparent from the following detailed description of the invention with reference to the accompanying drawings, in which: [ Figure 1 ] Figure 1 The steps of the method for manufacturing a starting structure according to the present invention are illustrated; [ Figure 2 ] Figure 2 It is a summary Figure 1 A flowchart of the manufacturing method steps; [ Figure 3 ] Figure 3 Examples Figure 1 and Figure 2 Variations of the method; [ Figure 4 ] Figure 4 Examples based on Figure 1 A method for creating an advanced structure from a starting structure; [ Figure 5 ] Figure 5 It is a summary Figure 4 A flowchart of the manufacturing method steps; and [ Figure 6 ] Figure 6 Examples Figure 4 and Figure 5 One of the steps in the method. Detailed Implementation

[0027] Embodiments of the present invention—Struct_0

[0028] An embodiment of the present invention is described in detail below, and is provided by Figures 1 to 3 Example.

[0029] Figure 1 The steps of a method 100 for manufacturing a first structure Struct_0 according to the present invention are illustrated. One object of this manufacturing method is to obtain a structure that can be used as a basis for manufacturing devices in the semiconductor industry. Specifically, the structure Struct_0 includes a layer TrLay supported by a substrate Sub2 via a graphene oxide layer GO, which can be degraded and / or reduced by infrared laser irradiation, causing the layer TrLay to detach from the substrate Sub2. The beneficial effects of this operation will be achieved by... Figures 4 to 6 This will be illustrated with examples.

[0030] Method 100 begins by providing two substrates, Sub1 and Sub2, each having two provisioning stages 110 and 120. In this embodiment of the invention, substrates Sub1 and Sub2 are composed of planar silicon carbide substrates, such as silicon carbide SiC wafers.

[0031] In steps 130 and 140, multilayer graphene layers MG1 and MG2, composed of carbon atoms (C), are formed on the surfaces of SiC substrates Sub1 and Sub2 by conventional heat treatment, preferably by sublimation of silicon atoms (Si) on the SiC surface. The number of graphene layers can be between 5 and 20, corresponding to a thickness between 1.5 nm and 14 nm. For example, see the article “Reversible graphitization of SiC: A route towards high-quality graphene on a minimally step bunched substrate” by Piotr Ciochon et al., published in Applied Surface Science 528 (2020) 146917. To facilitate the formation of graphene layers MG1 and MG2 through this step, the SiC substrate is preferably formed of single-crystal SiC.

[0032] Alternatively, the graphene layer can be obtained by chemical vapor deposition (CVD). In this case, the SiC substrate can be polycrystalline or monocrystalline.

[0033] In the implantation step 150 of at least one light material, the substrate Sub1 is prepared for the step of separating a layer TrLay of a portion thickness originating from the substrate Sub1, for example according to Smart Cut™ technology.

[0034] Therefore, substrate Sub1 must be prepared by introducing at least one light substance (e.g., hydrogen or helium) into the substrate. This introduction can correspond to hydrogen implantation, i.e., ion bombardment of hydrogen, which occurs here through the graphene layer MG1. As is known per se, and as Figure 1 As shown, hydrogen ions H + A weakening plane Frgl is injected to form the layer TrLay to be transferred. Relative to this weakening plane Frgl, layer TrLay lies on the side of graphene layer MG1.

[0035] The properties, dosage, and implantation energy of the implanted material are selected based on the thickness of the layer to be transferred and the physicochemical properties of the substrate Sub1. When the substrate Sub1 is made of SiC, an implantation dosage between 10-1 can be selected. 16 Up to 5×10 17 at / cm 2Hydrogen with an energy level between 30 and 300 keV is used to define a layer TrLay with a thickness of approximately 200 to 2000 nm.

[0036] In oxygenation steps 160 and 170, graphene layers MG1 and MG2 are oxidized to form graphene oxide layers GO1 and GO2, respectively. These operations can be performed, for example, according to the Hummers method or one of its derivatives, which involves treating the graphene layers in concentrated sulfuric acid (H2SO4) using KMnO4 and NaO3. See the article “Improved synthesis of graphene oxide” by Daniela C. Marcano et al., published in ACS Nano 2010, 4, 8, 4806–4814.

[0037] There are two reasons for performing these oxygenation steps.

[0038] The first reason is that the oxygenation of the graphene layers adds functional groups (carbonyl, hydroxyl, epoxy groups) to them, making them more hydrophilic, which makes it easier for the two layers to bond together in the subsequent step 200.

[0039] The second reason is that the chemical bond between carbon and oxygen atoms strongly absorbs CO at a wavelength of approximately 1087 cm⁻¹. -1 Infrared radiation (e.g., between 9 µm and 11 µm). This characteristic will be... Figures 4 to 6 The method 300 shown is utilized in step 340.

[0040] In bonding step 200, two substrates, Sub1 and Sub2, are bonded together by directly contacting graphene oxide layer GO1 with graphene oxide layer GO2. The two layers adhere to each other through molecular bonding. This forms a stack, Stck, which sequentially comprises substrate Sub2, layer GO2, layer GO1, and substrate Sub1. Substrate Sub1 includes a weakening plane Frgl. Layers GO1 and GO2 can be considered to collectively form the graphene oxide layer GO.

[0041] In the detachment step 210 following step 200, the substrate Sub1 splits into two parts at the weakening plane Frgl, according to the Smart Cut™ process in this example.

[0042] Therefore, in this embodiment, a portion of substrate Sub1 detaches from the rest of its volume to form the layer of interest, namely layer TrLay. As described above, this layer is defined by the volume of substrate Sub1 located between the weakening plane Frgl and the graphene layer MG1 (now graphene oxide layer GO1). After the bonding step of substrates Sub1 and Sub2, layer TrLay detaches from the rest of substrate Sub1 by breaking at the weakening plane Frgl and is thereby attached to support Sub2. The resulting assembly is labeled Struct_0, which is a structure that sequentially includes substrate Sub2, layer GO2, layer GO1, and layer TrLay transferred from substrate Sub1 to substrate Sub2.

[0043] The detachment step may therefore include applying a heat treatment to the stack Stck at a temperature ranging from approximately 80°C to 500°C, so that layer TrLay can detach and thus complete its transfer to the substrate Sub2. Alternatively or supplementing the heat treatment, this step may include applying a blade or a jet of gaseous or liquid fluid, or any other mechanical force, at the weakening plane Frgl.

[0044] In an optional step 220 following step 210, which leads to the detachment of the stack Stck, a stabilizing heat treatment may be applied to the stack Stck. The stabilizing heat treatment allows for the correction of crystal defects present in the TrLay layer. This heat treatment may be provided by bringing the stack to a temperature between 300°C and 600°C for a period between 30 minutes and 10 hours. This heat treatment is preferably performed by exposing the free surfaces of the dielectric layer to a neutral gas atmosphere.

[0045] After the layer TrLay detaches from the rest of the substrate Sub1, its free surface is not flat. In order to make it usable as a support, for example in the step of growing the layer by epitaxy, in the attachment to a third substrate, or in any other operation such as those commonly used in the semiconductor industry, it is necessary to prepare this surface, in particular to reduce its roughness, ideally making it atomically flat.

[0046] Therefore, in surface preparation step 230 (which may be before or after step 220), planarization and polishing are applied to layer TrLay. This may be a chemical mechanical polishing (CMP) process.

[0047] After surface treatment step 230 and (where applicable) stabilization step 220, structure Struct_0 can be considered usable, for example as a support when passing through an epitaxial layer.

[0048] Figure 3A variation of method 100 is illustrated. In this variation, a single graphene layer is formed and then oxidized. Preferably, a graphene layer that is not penetrated by ions during the formation of the weakening plane Frgl is retained. More specifically, method 100 remains unchanged except that a multilayer graphene MG1 is not formed and therefore not oxidized. Thus, during bonding step 200, the graphene oxide layer GO2 is in direct contact with the substrate Sub1. Therefore, this layer is formed directly on the material volume of the substrate Sub1 intended to form layer TrLay. In the stack Stck, layer TrLay is defined by the volume of the substrate Sub1 located between the weakening plane Frgl and the graphene layer GO2. Here, the graphene layer GO is formed solely by the graphene layer GO2.

[0049] An unillustrated variation of obtaining oxidized or oxygenated graphene layers is via a wet route: according to known methods, graphite powder can be suspended in an oxygen-containing liquid solution (typically the solution used in Hummers' method) to obtain graphene oxide in suspension, for example, via ultrasonic treatment. This suspension can then be directly spread onto a substrate to obtain an oxidized or oxygenated graphene layer.

[0050] The thickness of the graphene oxide layer GO2 and (where applicable) GO1 can be adjusted to define the thickness of the GO layer, with the aim of absorbing more or less a significant portion of the incident infrared radiation during subsequent laser separation steps. These thicknesses will be determined by the operator according to standards, depending on the properties of the layers to be separated.

[0051] Embodiments of the present invention—Struct_1

[0052] Figures 4 to 6 An example of using the method of structure Struct_0 is shown, in which the epitaxial layer Epi is formed directly on layer TrLay and then transferred to support Sub3.

[0053] This example illustrates obtaining an advanced structure Struct_1, which includes a support Sub3 that supports an epitaxial layer of gallium nitride (GaN).

[0054] The method 300 according to the invention begins with step 310 of providing a structure Struct_0, which, for example, is achieved through... Figures 1 to 3 The method shown in 100 is used to obtain it.

[0055] In epitaxial step 320, a gallium nitride (GaN) layer Epi is formed on a silicon carbide layer TrLay by epitaxy. Silicon carbide is known to be a good substrate for growing GaN with excellent crystal quality, and the GaN layer formed thereby can be considered as a single crystal.

[0056] In bonding step 330, substrate Sub3 is bonded to structure Struct_0 via layer Epi. Substrate Sub3 and layer Epi are in close contact and fixed to each other by molecular bonding, for example by direct hydrophilic bonding.

[0057] The substrate Sub3 is selected to be sufficiently flat and smooth to allow direct bonding to layer Epi. It can be, for example, a single-crystal silicon wafer or any other material used in the semiconductor industry, such as sapphire, polycrystalline SiC, single-crystal or polycrystalline AlN, or glass, or a combination of these materials. The substrate Sub3 is also selected to be compatible with the fabrication steps intended to be subsequently applied to layer Epi, such as photolithography, plasma processing, deposition of electrically insulating or conductive layers, ion implantation, thermal processing, or other fabrication steps used in the semiconductor industry.

[0058] In irradiation step 340, a laser beam with a wavelength in the infrared region (preferably between 9 µm and 11 µm) passes through the substrate Sub2 to irradiate the GO layer. The power density, beam scanning speed, and other parameters (e.g., the length and frequency of the irradiation pulses) are adjusted by the operator based on the transparency and thickness of the material through which the GO layer is irradiated, as well as the thickness of the GO layer itself. Under this irradiation Irr, the GO layer can be degraded through decomposition, such as... Figure 4 As shown and in Figure 5 The “X” indicates this. Alternatively and possibly commonly, depending on the irradiation parameters and therefore the temperature reached by the GO layer, irradiation Irr can induce a chemical reduction of the graphene oxide layer GO to form a reduced graphene oxide rGO with a volume much larger than that of graphene oxide. See Tung XuanTran et al., “Laser-Induced Reduction of Graphene Oxide by Intensity-Modulated Line Beam for Supercapacitor Applications”, ACS Appl. Mater. Interfaces, 2018, Nov 21; 10(46):39777-39784. This increase in volume can help push aside one of the other two layers surrounding the GO layer.

[0059] Therefore, the irradiation in step 340 allows the layer TrLay to be separated from the substrate Sub2 in step 350. This forms a structure that sequentially comprises the substrate Sub3, the epitaxial layer Epi, the transfer layer TrLay, and the remainder of the layer GO formed from graphene oxide and / or reduced graphene oxide rGO. Steps 340 and 350 can also be considered as a single irradiation and separation step.

[0060] In step 360, the remaining portion of layer GO and layer TrLay are removed to remove layer Epi. This cleaning can be performed by chemical mechanical polishing (CMP). This forms a structure that sequentially comprises a substrate Sub3 and a GaN layer Epi.

[0061] At any time after the step of bonding the substrate Sub3 to the structure Struct_0, a stabilization heat treatment step 370 can be applied to the formed assembly. The stabilization heat treatment allows for the correction of crystal defects present in the layer Epi and helps to solidify the bond between the layer Epi and the substrate Sub3. This heat treatment can be provided by bringing the stack to a temperature between 300°C and 600°C for a period between 30 minutes and 10 hours. This heat treatment is preferably performed by exposing the free surface of the dielectric layer to a neutral gas atmosphere. Performed after the step 360 of removing the layer TrLay, this treatment can advantageously repair the damage to the layer Epi caused by step 350. At the end of the above steps, the structure Struct_1 is obtained.

[0062] Other methods exist for obtaining thin gallium nitride (GaN) layers and transferring them onto acceptor substrates, particularly those using SmartCut™ technology. This technology is based on forming a weakening plane in a thick donor substrate, such as a single-crystal wafer obtained from a bulk single-crystal ball of the desired material. The depth of this weakening plane defines the thickness of the material layer that can be detached from the wafer. This weakening plane is obtained by implanting light matter ions into the wafer through one surface. However, the depth of this implantation plane is limited by the maximum accelerating voltage of commercially available ion implantation equipment. Therefore, the thickness of the layer that can detach from the donor substrate is limited by the maximum implantation depth of the ions used to form the weakening plane.

[0063] In contrast, the method 300 described above (applied herein to gallium nitride) advantageously allows for the avoidance of this thickness limitation while permitting easy transfer of the resulting layer. Specifically, the Epi layer can be epitaxial at any thickness (while still limited by the critical epitaxial thickness), independent of the available ion implantation equipment. Next, a support substrate is bonded to the epitaxial layer.

[0064] Alternative implementation methods

[0065] The above example involves forming layer Struct_0 using silicon carbide (SiC) substrates Sub1 and Sub2. Other substrates may be used, provided that at least one of them is compatible with the formation and oxygenation process of the graphene layer. Substrates such as sapphire, polycrystalline SiC, single-crystal or polycrystalline AlN, or glass, or combinations of these materials, may be mentioned, but any other substrate that meets the above compatibility requirements may be used, such as those used in the semiconductor industry.

[0066] Regarding the formation of structure Struct_1, in addition to the conditions described above, an additional condition is that the substrate Sub2 (via the GO layer support layer TrLay) is substantially transparent to the wavelength used during the GO irradiation step. Again, it can be mentioned that silicon carbide and silicon substrates are used for Sub2. "Substantially transparent" means that at least 10% of the wavelength in question is transmitted through the substrate.

[0067] Alternatively, although this is not the preferred method, the GO layer can be irradiated through the substrate Sub3 and the TrLay layer. In this case, the substrate Sub3 must be substantially transparent to the wavelength used during the GO irradiation step. In this case, silicon carbide and silicon substrates can again be mentioned for Sub3.

[0068] In this document, the accompanying drawings are not necessarily drawn to scale. Some features and components may be shown in an exaggerated or schematic manner relative to other components, and for the purpose of clarity and brevity, some details of conventional elements may not be shown.

[0069] Of course, the present invention is not limited to the described embodiments, and variations may be introduced without departing from the scope of the invention as defined by the claims.

Claims

1. A starting structure (Struct_0) designed to withstand laser irradiation separation, the starting structure comprising a substrate (Sub2), a transfer layer (TrLay), and a graphene oxide layer (GO, GO2) interposed between the substrate (Sub2) and the transfer layer (TrLay), wherein, The transfer layer is composed of single-crystal silicon carbide (SiC) or sapphire.

2. The structure according to claim 1, wherein, The substrate (Sub2) is transparent to infrared radiation.

3. The structure according to claim 1, wherein, The substrate (Sub2) is transparent to radiation with wavelengths between 9 µm and 11 µm.

4. The structure according to any one of claims 1 to 3, wherein, The substrate is made of silicon (Si) or silicon carbide (SiC).

5. A method (100) for manufacturing a starting structure (Struct_0) designed to be separated by laser irradiation, the starting structure comprising a substrate (Sub2), a transfer layer (TrLay), and a graphene oxide layer (GO, GO2) interposed between the substrate (Sub2) and the transfer layer (TrLay), the method comprising: - Steps (110, 120) to provide two substrates (Sub1, Sub2); - Step (130, 140) to form at least one multilayer graphene layer (MG1, MG2) on at least one of the two substrates (Sub1, Sub2). - The step (160, 170) of oxidizing the at least one multilayer graphene layer to form at least one graphene oxide layer (GO1, GO2). - Step (200) of bonding the two substrates (Sub1, Sub2) via the at least one graphene oxide layer (GO1, GO2, GO). as well as - Step (210) of removing a portion of one of the two substrates (Sub1) to leave the transfer layer (TrLay) on the other substrate (Sub2) of the two substrates.

6. The manufacturing method according to claim 5, wherein, The joining step (200) is performed by direct contact.

7. The manufacturing method according to claim 5 or 6, wherein, A multilayer graphene layer (MG1, MG2) is formed on each of the two substrates (Sub1, Sub2).

8. The method according to any one of claims 5 to 7, the method further comprising the step (150) of ion implantation in the first substrate (Sub1) to form a weakening plane (Frgl) in the first substrate (Sub1) thereby defining the transfer layer (TrLay).

9. The method according to any one of claims 5 to 8, wherein, The transfer layer (TrLay) is composed of single-crystal silicon carbide (SiC) or sapphire.

10. A method (300) for manufacturing an advanced structure (Struct_1), the advanced structure comprising a layer (Epi) epitaxially formed on a transfer layer (TrLay) of a starting structure (Struct_0), the starting structure being designed to be separated by laser irradiation, the starting structure comprising a substrate (Sub2), the transfer layer (TrLay), and a graphene oxide layer (GO, GO2) interposed between the substrate (Sub2) and the transfer layer (TrLay), the method comprising the following steps: - Provide the starting structure (Struct_0) described in (310); - The layer (Epi) is formed by epitaxy on the transfer layer (TrLay) of the provided structure (Struct_0). - The third substrate (Sub3) is bonded (330) to the structure (Struct_0) by directly contacting the third substrate (Sub3) with the epitaxial layer (Epi); and - Irradiate (340) the graphene oxide layer (GO) by infrared irradiation (Irr) in order to separate the transfer layer (TrLay), the epitaxial layer (Epi) and the third substrate (Sub3) from the substrate (Sub2) of the starting structure (Struct_0) (350).

11. The method according to claim 10, wherein, The irradiation (Irr) uses electromagnetic waves with wavelengths between 9 µm and 11 µm.

12. The method according to claim 10 or 11, the method further comprising a step (360) of removing the layer (Epi) after the separation step (350).

13. The method according to any one of claims 10 to 12, wherein, The epitaxial layer is a gallium nitride (GaN) layer.

14. The method according to any one of claims 10 to 13, wherein, The transfer layer (TrLay) is composed of single-crystal silicon carbide (SiC) or sapphire.

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