Process for manufacturing a crystal on a crystalline substrate

Abstract

A process for manufacturing a crystal (1) on a crystalline substrate (2), comprising the steps: a) modeling an interface (I) between a crystalline lattice of the crystal (1) and a crystalline lattice of the crystalline substrate (2); b) determining a spatial distribution of an elastic potential energy at the interface (I) modeled in step a); c) identifying minima (Emin) of the elastic potential energy from the spatial distribution determined in step b); d) forming a nanostructured interfacial layer on the crystalline substrate (2); the interfacial layer comprising through-channel nanotunnels arranged according to a distribution corresponding to the minima (Emin) of the elastic potential energy identified in step c); the interfacial layer being formed of a material different from the crystal (1) and the crystalline substrate (2);e) form the crystal (1) on the interfacial layer, via the traversing nanotunnels delimiting nucleation sites (20) of the crystalline substrate (2). Figure 5;

Description

Title of the invention: Method for manufacturing a crystal on a crystalline substrate Technical field

[0001] The invention relates to the technical field of manufacturing a crystal on a crystalline substrate.

[0002] The invention finds its application in particular in the epitaxy of a supercrystal on a surface of a crystalline substrate, the supercrystal and the crystalline substrate having a lattice mismatch. State of the art

[0003] A method known from the state of the art consists of conventional epitaxy of a crystal on a crystalline substrate. When the crystal and the crystalline substrate have a lattice mismatch, such conventional epitaxy is generally defective beyond a critical thickness of the crystal. Indeed, the elastic potential energy resulting from the deformations is likely to generate defects such as dislocations.

[0004] Solutions have been considered, such as the growth of a buffer layer intercalated between the crystalline substrate and the crystal to be epitaxially grown. However, such a solution is not entirely satisfactory because it always generates the presence of defects, as well as fluctuations in residual deformations, and requires a significant operating time with numerous technological steps.

[0005] Processes of nano-heteroepitaxy of the crystal and nano-structuring (“nano-patterning” in English) of the crystalline substrate are also known, but also lead to residual defects.

[0006] The person skilled in the art is therefore seeking a solution for manufacturing a crystal on a crystalline substrate which makes it possible to drastically reduce the formation of defects within the crystal, in particular in the case of a strong lattice mismatch (>10%) between the crystal and the crystalline substrate. Statement of the invention

[0007] The invention aims to remedy all or part of the aforementioned drawbacks. To this end, the invention relates to a method for manufacturing a crystal on a crystalline substrate, comprising the steps: a) model an interface between a crystal lattice of the crystal and a crystal lattice of the crystalline substrate; b) determine a spatial distribution of an elastic potential energy at the interface modeled during step a); c) identify minima of the elastic potential energy from the spatial distribution determined during step b); d) forming a nanostructured interfacial layer on the crystalline substrate; the interfacial layer comprising through nanotunnels, arranged according to a distribution corresponding to the minima of the elastic potential energy identified during step c); the interfacial layer being formed from a material different from the crystal and the crystalline substrate; e) form the crystal on the interfacial layer, via the crossing nanotunnels delimiting nucleation sites of the crystalline substrate.

[0008] Thus, such a method according to the invention makes it possible to envisage epitaxy of a crystal (in particular a supercrystal) over a large surface area of ​​the crystalline substrate, thanks to a prior identification of the minima of elastic potential energy resulting from steps a), b) and c). The nanostructured interfacial layer, formed during step d), makes it possible to expose only areas of the crystalline substrate favorable to epitaxial growth, thanks to the distribution of the through nanotunnels. Indeed, these areas of the crystalline substrate exposed at the end of step d) have minima of elastic potential energy, thus minimizing the interfacial defect, and thus constituting privileged nucleation sites. The areas of the crystalline substrate unfavorable to epitaxial growth (i.e.with a high elastic potential energy, above the threshold energy for crystal defect formation) are reservoirs of crystal defects masked by the interfacial layer and are therefore not accessible as nucleation sites during step e).

[0009] The interfacial layer is formed from a material different from the crystal and different from the crystalline substrate in order to avoid future competition of the materials, for example during the formation of the crystal by epitaxy during step e).

[0010] The method according to the invention may comprise one or more of the following characteristics.

[0011] According to a characteristic of the invention, the interfacial layer formed during step d) is a monolayer forming a two-dimensional material.

[0012] Thus, one advantage provided is to be able to spatially delimit the distribution of the through nanotunnels with great precision. Another advantage lies in the great ability of the majority of two-dimensional materials to accommodate higher shears than three-dimensional materials. This significant local translational flexibility ("compliance" in English) makes it possible to obtain a very broad distribution of interfacial atomic bond angles, instead of forming more extensive defects such as dislocations classically observed for three-dimensional materials.

[0013] According to a characteristic of the invention, the material of the interfacial layer formed during step d) is in solid phase or in gas phase.

[0014] According to a characteristic of the invention, the solid phase material of the interfacial layer formed during step d) is chosen from: - a dichalcogenide of a transition metal, preferably molybdenum disulfide MoS2, tin disulfide SnS2, tungsten disulfide WS2, vanadium disulfide VS2, titanium disulfide TiS2; - graphene or a graphene derivative, the graphene derivative preferably being an amorphous carbon, in particular hydrogenated, a diamond-type carbon, a haeckelite structure; - a boron nitride BN, in particular hydrogenated, preferably hexagonal; - a material with the empirical formula SiOxCyHz; - a block copolymer, preferably self-organized; - a carbide of a transition metal, preferably of the MXene type; - a metallo-organic network, - borophene, silicene, germanene, stanene, phosphorene.

[0015] According to a characteristic of the invention, the gaseous phase material of the interfacial layer formed during step d) is chosen from dihydrogen H2, dinitrogen N2, dioxygen O2, argon Ar, helium He, air, neon Ne, krypton Kr, xenon Xe, carbon monoxide CO, carbon dioxide CO2.

[0016] According to a characteristic of the invention, the interfacial layer formed during step d) has a thickness of between 1 μm and 5 nm.

[0017] According to a characteristic of the invention, step d) comprises the steps: di) forming an interfacial layer on the crystalline substrate; d2) nanostructuring the interfacial layer by forming through nanotunnels, arranged according to a distribution corresponding to the minima of the elastic potential energy identified during step c).

[0018] According to a characteristic of the invention, step dj is executed by a technique chosen from: - a collage, a collage with surface activation, a hybrid collage, a collage by atomic diffusion; - a pulsed laser deposit; - physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic layer deposition, plasma-enhanced atomic layer deposition, ion beam-enhanced deposition, electron beam-enhanced deposition, ion beam-enhanced deposition; - a spray; - evaporation; - additive growth; - epitaxy, molecular beam epitaxy, solid phase epitaxy, pulsed laser induced epitaxy.

[0019] According to a characteristic of the invention, step d2) is executed by a technique chosen from: - etching through a mask, the etching being able to be dry etching, wet etching or plasma etching; the mask preferably being self-organized; - ion beam lithography, preferably helium ions; - electron beam lithography; - proton beam lithography; - nano-imprint lithography, preferably with pyramidal patterns; - scanning probe lithography, preferably thermal scanning; - extreme ultraviolet lithography.

[0020] According to a characteristic of the invention, step d2) is followed by a step d20) applying a cleaning of the nanostructured interfacial layer, adapted to remove residues from the nanostructuring carried out during step d2).

[0021] According to a characteristic of the invention, step d20) is executed by: - chemical, vapor phase, liquid phase, or plasma type cleaning; or by - ion beam etching.

[0022] Thus, an advantage provided is to be able to remove residues from the nanostructuring, as well as possibly modifying the selectivity of the crystal deposits in the nanotunnels.

[0023] According to a characteristic of the invention, step d2) is followed by a step d2i) applying a surface treatment of the nanostructured interfacial layer with hydrogen ions, preferably implanted or in the form of a plasma.

[0024] Thus, an advantage provided is to deoxidize the surface, passivate the dangling bonds, and reduce the defectivity of the epitaxial interface. Such a surface treatment can also modify the selectivity of the crystal depositions in the nanotunnels because the passivation of the dangling bonds temporarily blocks the formation of interatomic bonds.

[0025] According to a characteristic of the invention, step e) is carried out by a technique chosen from: - bonding, direct bonding, laser-assisted direct bonding, bonding with surface activation which may be under vacuum, hybrid bonding, eutectic bonding, thermocompression bonding, atomic diffusion bonding, anodic bonding, wet bonding which may be hydrophilic or hydrophobic, plasma-activated bonding, ultraviolet bonding; - a pulsed laser deposit; - physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic layer deposition, plasma-enhanced atomic layer deposition, ion beam-enhanced deposition, electron beam-enhanced deposition, ion beam-enhanced deposition; - a spray; - evaporation, preferably under vacuum; - additive growth; - a deposit with a toumette; - a screen print; - epitaxy, remote epitaxy, molecular beam epitaxy, solid phase epitaxy, pulsed laser induced epitaxy, organometallic vapor phase epitaxy.

[0026] According to a characteristic of the invention, step b) comprises a step chosen from: (bi) performing an atomistic calculation of the interface modeled in step (a) using an interatomic potential; or b'i) obtain a Moiré pattern of the interface modeled in step a); or b”i) perform an initial ah calculation of a structure of the interface modeled in step a); steps bj, b'i) and b” J being implemented by means of a computer.

[0027] According to a characteristic of the invention, step a) comprises a step aj of constructing crystal meshes of the crystal on crystal meshes of the crystalline substrate; step aO being implemented by means of a computer.

[0028] Definitions

[0029] - By "crystal / crystalline" we mean a solid whose constituents are assembled in regular manner. In other words, the diffraction pattern is essentially discrete, according to the definition officially given by the International Union of Crystallography (IUCR). The solid can be monocrystalline or polycrystalline, but not amorphous.

[0030] - By "substrate" is meant a self-supporting physical medium. A substrate may be a slice (also called "platelet", "wafer" in English) which generally comes in the form of a disc resulting from a cut in an ingot of a crystalline material.

[0031] - By "crystal lattice" is meant the periodic spatial repetition of patterns (called crystal lattices) defining the crystalline structure of the crystal or crystalline substrate.

[0032] - By "elastic potential energy" we mean the elastic energy of deformation in a crystalline solid, linked to the elastic interaction between the constituents (eg atoms) of the crystalline solid. We also speak of potential interaction energy or elastic energy.

[0033] - By "interfacial layer" is meant a layer forming an interface between the crystalline substrate and the crystal.

[0034] - By "nanostructured" we mean a layer comprising patterns, generally periodic, nanometric or subnanometric size.

[0035] - By "through nanotunnels" we mean nanometric sized orifices, crossing the interfacial layer from one side to the other.

[0036] - By "arranged according to a distribution corresponding to the minima of the energy po elastic potential energy”, we mean that each crossing nanotunnel is located in a region of the interfacial layer centered on a minimum of the elastic potential energy. The region of the interfacial layer, centered on a minimum of the elastic potential energy, is circumscribed by a region of the interfacial layer where the elastic potential energy is strictly lower than the minimum energy for the formation of extended defects. In other words, the iso-energy curve of each crossing nanotunnel, defining their contour, is inscribed in a region of the interfacial layer where the elastic potential energy is strictly lower than the minimum energy for the formation of extended defects.

[0037] - By "nucleation sites" is meant areas of the crystalline substrate conducive to the formation of a transition between two crystalline solid phases. These are also called nucleation sites.

[0038] - By "two-dimensional material" is meant a material consisting of a single layer of constituents (eg atoms, molecules). We also speak of monolayer material or 2D material.

[0039] - By "thickness" is meant the dimension along the normal to the surface of the substrate crystalline on which the interfacial layer is formed.

[0040] - By "atomistic calculation" we mean the calculation of the elastic potential energy at the atomic scale, for example using an (empirical) interatomic potential or an ab initio calculation. This type of calculation makes it possible to predict the position of all atoms, particularly at the interface, by global minimization of the total energy of the system.

[0041] - By "Moire pattern" we mean a pattern resulting from the superposition of spots representative of the atoms of the crystal lattice of the crystal and spots representative of the atoms of the lattice of the crystal substrate, and resulting from a phenomenon of spatial interference between the two lattices.

[0042] - By "ab initia calculation" we mean a calculation of the elastic potential energy which is based on basic physical laws, such as the Schrodinger equation. Brief description of the drawings

[0043] Other characteristics and advantages will appear in the detailed description of different embodiments of the invention, the description being accompanied by examples and references to the attached drawings.

[0044] [Fig-1] is a schematic perspective view, illustrating a step d) of a method according to the invention.

[0045] [Fig.2] is a schematic sectional view, illustrating a step d) of a method according to the invention.

[0046] [Fig.3] is a schematic perspective view, illustrating a step d) of a method according to the invention.

[0047] [Fig.4] is a schematic perspective view, illustrating a formation of a interfacial layer on a crystalline substrate, the minima of the elastic potential energy of the interface being visible in transparency.

[0048] [Fig.5] is a schematic perspective view, illustrating a nanostructuring of the interfacial layer illustrated in [Fig.4].

[0049] [Fig.6] is a schematic top view, in transparency, illustrating a step b'i) of a method according to the invention.

[0050] [Fig.7] is a schematic top view, in transparency, illustrating a step c) of a method according to the invention.

[0051] [Fig.8] is a schematic perspective view, illustrating the formation of defects in the vicinity of through nanotunnels of too small size.

[0052] [Fig.9] is a schematic top view, in transparency, illustrating a step a) of a method according to the invention.

[0053] [Fig. 10] is a schematic top view, in transparency, illustrating a step of determining an elastic iso-energy line corresponding to the formation energy of an interfacial defect.

[0054] It should be noted that the drawings described above are schematic, and are not necessarily to scale for the sake of readability and to simplify their understanding. The sections are made along the normal to the surface of the crystalline substrate on which the interfacial layer is formed. Detailed description of the implementation methods

[0055] Elements that are identical or provide the same function will bear the same references for the different embodiments, for the sake of simplification.

[0056] An object of the invention is a method of manufacturing a crystal 1 on a crystalline substrate 2, comprising the steps: a) model an interface I between a crystal lattice of crystal 1 and a crystal lattice of crystalline substrate 2; b) determine a spatial distribution of an elastic potential energy at the interface I modeled during step a); c) identify minima Emin of the elastic potential energy from the spatial distribution determined during step b); d) forming a nanostructured interfacial layer 3 on the crystalline substrate 2; the interfacial layer 3 comprising through nanotunnels 30, arranged according to a distribution corresponding to the minima Emin of the elastic potential energy identified during step c); the interfacial layer 3 being formed from a material different from the crystal and the crystalline substrate; e) forming the crystal 1 on the interfacial layer 3, via the through nanotunnels 30 delimiting nucleation sites 20 of the crystalline substrate 2.

[0057] Step a)

[0058] An interface I between a crystal lattice of crystal 1 and a crystal lattice of crystalline substrate 2 is modeled during step a). As a non-limiting example, crystal 1 may be aluminum nitride AIN

[001] and crystalline substrate 2 may be gallium nitride GaN

[001] . Of course, any interface I between two crystalline materials having a lattice mismatch may be modeled during step a).

[0059] Step a) advantageously comprises a step ai) constructing crystal meshes of crystal 1 on crystal meshes of crystalline substrate 2. Step ai) is advantageously implemented using a computer. By way of non-limiting example, step aO can be executed using the VESTA software in order to visualize the positions of the atoms from position files. In the case of new and unpublished crystals, an ab initio calculation makes it possible to predict the atomic positions and to generate the position file.

[0060] Step b)

[0061] A spatial distribution of an elastic potential energy at the interface I modeled during step a) is determined during step b).

[0062] Step b) advantageously comprises a step chosen from: (bi) performing an atomistic calculation of the interface I modeled in step (a) using an interatomic potential; or b) obtain a Moiré pattern of the interface I modeled in step a); or b”i) perform an ab initio calculation of a structure of the interface I modeled in step a).

[0063] Steps bi), b'i) and b”i) are advantageously implemented by means of a computer.

[0064] As a non-limiting example, the (empirical) interatomic potential used during step bi) can be calculated by a Keating-type potential known to those skilled in the art, or for example using an interatomic potential obtained by a technique artificial intelligence. Other interatomic potentials can be used, for example the Embedded Atom Method (EAM) potential, the Modified Embedded Atom Method (MEAM) potential, the Angular Dependent Potential (ADP) etc. Step bj can be performed by a molecular dynamics type method, or similar.

[0065] As a non-limiting example, the Moiré pattern can be obtained during step b' i ) by digitally superimposing the spots representative of the atoms using software for representing atomic positions (eg VESTA). The exploratory variation of the size of the atomic spots in the software makes it possible to adjust the contrast of the Moiré.

[0066] As a non-limiting example, the ab initio calculation of the structure can be carried out by a so-called mean field approach, or by a so-called perturbative approach, these approaches being known to those skilled in the art.

[0067] Step c)

[0068] Minima Emin of the elastic potential energy are identified during step c), from the spatial distribution determined during step b).

[0069] The spatial distribution determined during step b) can also highlight maxima Emax of the elastic potential energy, potential reservoirs of defects, which will be masked by the interfacial layer 3 covering these zones.

[0070] Step d)

[0071] A nanostructured interfacial layer 3 is formed on the crystalline substrate 2 during step c).

[0072] The interfacial layer 3 comprises through nanotunnels 30, arranged according to a distribution corresponding to the minima Emin of the elastic potential energy identified during step c). More precisely, the through nanotunnels 30 are arranged according to a distribution corresponding to all or part of the minima Emin of the elastic potential energy identified during step c). Each through nanotunnel 30 is located in a zone of the interfacial layer 3 centered on a minimum Emin of the elastic potential energy. The zone of the interfacial layer 3, centered on a minimum Emin of the elastic potential energy, is circumscribed by a region of the interfacial layer 3 where the elastic potential energy is strictly lower than the minimum energy for the formation of extended defects.In other words, the iso-energy curve of each nanotunnel 30 crossing, defining their contour, is inscribed in a region of the interfacial layer 3 where the elastic potential energy is strictly lower than the minimum energy for the formation of extended defects.

[0073] The dimension of the through nanotunnels 30 is advantageously calculated from atomistically by comparing the local elastic potential energy and the formation energy of extended defects that would be likely to form in the absence of through-nanotunnels 30. If the local elastic potential energy is greater than the critical threshold of formation energy of extended defects, then this type of defect is likely to be formed. Thus, any area with an elastic potential energy locally greater than the threshold of formation of extended defects is masked by the through-nanotunnels 30 to avoid the germination of this type of defect. The optimal size of the through-nanotunnels 30 is obtained by iterations, for example by replacing atoms followed by minimizing the energy of the system, so as to obtain an interfacial elastic potential energy always below the critical threshold of formation of extended defects.More precisely, an atomistic calculation makes it possible to obtain iso-energy curves Eiso, for a given formation energy of a defect (denoted Ef), defining the limit of the contour to be respected for the nanostructuring, i.e. the critical contour not to be exceeded for the through-nanotunnels 30. In other words, the through-nanotunnels 30 must extend over an area less than or equal to the area of ​​the contour delimited by the iso-energy curve Eiso. The geometry of the through-nanotunnels 30 depends on the crystalline phases and the crystalline orientations at the interface I modeled during step a). In particular, when the dimensions of the through-nanotunnels 30 are too large (i.e. area greater than the area of ​​the contour delimited by the iso-energy curve Eiso), defects form in the most constrained regions corresponding to the locally highest elastic potential energy.It is therefore necessary to choose the iso-energy curve Eiso, defining the contour of the crossing nanotunnels 30, allowing the relation Eiso < Ef to be verified.

[0074] The interfacial layer 3 is formed from a material that is different from both the material of the crystal and the material of the crystalline substrate. The material of the interfacial layer 3 formed during step d) may be in the solid phase or in the gas phase.

[0075] The solid phase material of the interfacial layer 3 formed during step d) is advantageously chosen from: - a dichalcogenide of a transition metal, preferably molybdenum disulfide MoS2, tin disulfide SnS2, tungsten disulfide WS2, vanadium disulfide VS2, titanium disulfide TiS2; - graphene or a graphene derivative, the graphene derivative preferably being an amorphous carbon, in particular hydrogenated, a diamond-type carbon, a haeckelite structure; - a boron nitride BN, in particular hydrogenated, preferably hexagonal; - a material with the empirical formula SiOxCyHz; - a block copolymer, preferably self-organized; - a carbide of a transition metal, preferably of the MXene type; - a metallo-organic network, - borophene, silicene, germanene, stanene, phosphorene.

[0076] The gas-phase material of the interfacial layer 3 formed during step d) is advantageously chosen from dihydrogen H2, dinitrogen N2, dioxygen O2, argon Ar, helium He, air, neon Ne, krypton Kr, xenon Xe, carbon monoxide CO, carbon dioxide CO2. In this embodiment, the through nanotunnels 30 are filled with the gas-phase material and are formed concomitantly with the interfacial layer 3. The gas-phase material of the interfacial layer 3 formed during step d) may be precursor gases, more precisely growth gas residues that have not reacted.

[0077] The interfacial layer 3 formed during step d) advantageously has a thickness of between 1 μm and 5 nm. The interfacial layer 3 formed during step d) is advantageously a monolayer forming a two-dimensional material. However, it is possible to stack several monolayers (each forming a two-dimensional material) to adjust the thickness of the interfacial layer 3 formed during step d). It is the atomistic simulation which gives the optimal thickness of the interfacial layer 3.

[0078] Step d) advantageously comprises the steps: di) forming an interfacial layer 3 on the crystalline substrate 2; d2) nanostructuring the interfacial layer 3 by forming through nanotunnels 30, arranged according to a distribution corresponding to the minima Emin of the elastic potential energy identified during step c).

[0079] Step di) is advantageously carried out by a technique chosen from: - a collage, a collage with surface activation, a hybrid collage, a collage by atomic diffusion; - a pulsed laser deposit; - physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic layer deposition, plasma-enhanced atomic layer deposition, ion beam-enhanced deposition, electron beam-enhanced deposition, ion beam-enhanced deposition; - a spray; - evaporation; - additive growth; - epitaxy, molecular beam epitaxy, solid phase epitaxy, pulsed laser induced epitaxy.

[0080] Step d2) is advantageously carried out by a technique chosen from: - etching through a mask, the etching being able to be dry etching, wet etching or plasma etching; the mask preferably being self-organized; - ion beam lithography, preferably helium ions; - electron beam lithography; - proton beam lithography; - nano-imprint lithography, preferably with pyramidal patterns; - scanning probe lithography, preferably thermal scanning; - extreme ultraviolet lithography.

[0081] Step d2) is advantageously followed by a step d20) applying a cleaning of the nanostructured interfacial layer 3, the cleaning being adapted to remove residues from the nanostructuring carried out during step d2). Step d20) is advantageously carried out by: - chemical, vapor phase, liquid phase, or plasma type cleaning; or by - ion beam etching.

[0082] Step d2) is advantageously followed by a step d2i) applying a surface treatment of the nanostructured interfacial layer 3 with hydrogen ions. The hydrogen ions are preferably implanted or in the form of a plasma.

[0083] As an example of a simple implementation of step d), it is possible to nano-structure beforehand an interfacial layer 3 (e.g. a two-dimensional material) on a temporary support. Through nanotunnels 30 can be formed within the two-dimensional material, for example with a helium beam, an electron beam, or with a heated tip. The assembly comprising the temporary support and the nanostructured two-dimensional material is then turned over and bonded to the crystalline substrate 2. Then the temporary support is removed, as are any residues. An advantage of this example of implementation is that the crystalline substrate 2 is not impacted by the step of forming the through nanotunnels 30.

[0084] Step e)

[0085] The crystal 1 is formed on the interfacial layer 3 during step e), via the through nanotunnels 30 delimiting nucleation sites 20 of the crystalline substrate 2.

[0086] Step e) is advantageously carried out by a technique chosen from: - bonding, direct bonding, laser-assisted direct bonding, bonding with surface activation which may be under vacuum, hybrid bonding, eutectic bonding, thermocompression bonding, atomic diffusion bonding, anodic bonding, wet bonding which may be hydrophilic or hydrophobic, plasma-activated bonding, ultraviolet bonding; - a pulsed laser deposit; - physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic layer deposition, deposition plasma-assisted atomic layer deposition, ion beam-assisted deposition, electron beam-assisted deposition, ion beam deposition; - a spray; - evaporation, preferably under vacuum; - additive growth; - a deposit with a toumette; - a screen print; - epitaxy, remote epitaxy, molecular beam epitaxy, solid phase epitaxy, pulsed laser induced epitaxy, organometallic vapor phase epitaxy.

[0087] Step e) may be followed by a step ej applying thermal annealing, preferably in a chemically controlled atmosphere, adapted to vaporize the interfacial layer 3. According to an alternative, the thermal annealing may be adapted to recrystallize layers.

[0088] As an example of a simple implementation of step e), after removal of the temporary support and any residues, crystal 1 is deposited and thermal annealing is applied to obtain epitaxy inside the through nanotunnels 30. The extension of the crystalline zones around the through nanotunnels 30 is calculated to result in a single crystal by extension and fusion of the epitaxial growth grains initiated in the through nanotunnels 30.

[0089] The invention is not limited to the embodiments disclosed. Those skilled in the art are able to consider their technically effective combinations and to substitute equivalents for them.

Claims

Claims

1. Method for manufacturing a crystal (1) on a crystalline substrate (2), comprising the steps: a) modeling an interface (I) between a crystal lattice of the crystal (1) and a crystal lattice of the crystalline substrate (2); b) determining a spatial distribution of an elastic potential energy at the interface (I) modeled during step a); c) identifying minima (Emin) of the elastic potential energy from the spatial distribution determined during step b); d) forming a nanostructured interfacial layer (3) on the crystalline substrate (2); the interfacial layer comprising through nanotunnels (30), arranged according to a distribution corresponding to the minima (Emin) of the elastic potential energy identified during step c); the interfacial layer (3) being formed of a material different from the crystal (1) and the crystalline substrate (2);e) forming the crystal (1) on the interfacial layer (30), via the through nanotunnels (30) delimiting nucleation sites (20) of the crystalline substrate (2);

2. A method according to claim 1, wherein the interfacial layer (3) formed in step d) is a monolayer forming a two-dimensional material.

3. A method according to claim 1 or 2, wherein the material of the interfacial layer (3) formed during step d) is in the solid phase or in the gas phase.

4. Method according to claim 3, wherein the solid phase material of the interfacial layer (3) formed during step d) is chosen from: - a dichalcogenide of a transition metal, preferably molybdenum disulfide MoS2, tin disulfide SnS2, tungsten disulfide WS2, vanadium disulfide VS2, titanium disulfide TiS2; - graphene or a graphene derivative, the graphene derivative preferably being an amorphous carbon, in particular hydrogenated, a diamond-type carbon, a haeckelite structure; - a boron nitride BN, in particular hydrogenated, preferably hexagonal; - a material of empirical formula SiOxCyHz; - a block copolymer, preferably self-organized; - a carbide of a transition metal, preferably of the MXene type; - a metallo-organic network, - borophene, silicene, germanene, stanene, phosphorene.

5. Method according to claim 3, in which the gaseous phase material of the interfacial layer (3) formed during step d) is chosen from dihydrogen H2, dinitrogen N2, dioxygen O2, argon Ar, helium He, air, neon Ne, krypton Kr, xenon Xe, carbon monoxide CO, carbon dioxide CO2.

6. Method according to one of claims 1 to 5, in which the interfacial layer (3) formed during step d) has a thickness of between 1 pm and 5 nm.

7. Method according to one of claims 1 to 6, in which step d) comprises the steps: di) forming an interfacial layer (3) on the crystalline substrate (2); d2) nanostructuring the interfacial layer (3) by forming through nanotunnels (30), arranged according to a distribution corresponding to the minima (Emin) of the elastic potential energy identified during step c).

8. The method of claim 7, wherein step di) is performed by a technique selected from: - bonding, surface-activated bonding, hybrid bonding, atomic diffusion bonding; - pulsed laser deposition; - physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic layer deposition, plasma-enhanced atomic layer deposition, ion beam-enhanced deposition, electron beam-enhanced deposition, ion beam-enhanced deposition; - sputtering; - evaporation; - additive growth; - epitaxy, molecular beam epitaxy, solid-phase epitaxy, pulsed laser-induced epitaxy.

9. Method according to claim 7 or 8, in which step d2) is carried out by a technique chosen from: - etching through a mask, the etching being able to be a dry etching, a wet etching or a plasma etching; the mask preferably being self-organized; - ion beam lithography, preferably helium ions; - electron beam lithography; - proton beam lithography; - nanoimprint lithography, preferably with pyramidal patterns; - scanning probe lithography, preferably thermal scanning; - extreme ultraviolet lithography.

10. Method according to one of claims 7 to 9, in which step d2) is followed by a step d20) applying a cleaning of the nanostructured interfacial layer (3), adapted to remove residues from the nanostructuring carried out during step d2).

11. Method according to claim 10, wherein step d20) is carried out by: - ​​chemical, vapor phase, liquid phase, or plasma type cleaning; or by - ion beam etching.

12. Method according to one of claims 7 to 11, in which step d2) is followed by a step d2[) applying a surface treatment of the nanostructured interfacial layer (3) with hydrogen ions, preferably implanted or in the form of a plasma.

13. Method according to one of claims 1 to 12, wherein step e) is carried out by a technique chosen from: - bonding, direct bonding, laser-assisted direct bonding, bonding with surface activation which may be under vacuum, hybrid bonding, eutectic bonding, thermocompression bonding, atomic diffusion bonding, anodic bonding, wet bonding which may be hydrophilic or hydrophobic, bonding with plasma activation, ultraviolet bonding; - pulsed laser deposition; - physical vapor deposition, chemical vapor deposition, plasma-enhanced chemical vapor deposition, atomic layer deposition, plasma-enhanced atomic layer deposition, ion beam-enhanced deposition, electron beam-enhanced deposition, ion beam-enhanced deposition; - sputtering; - evaporation, preferably under vacuum; - additive growth; - spin coating; - a screen print; - epitaxy, remote epitaxy, molecular beam epitaxy, solid phase epitaxy, pulsed laser induced epitaxy, organometallic vapor phase epitaxy.

14. Method according to one of claims 1 to 13, in which step b) comprises a step chosen from: (bi) performing an atomistic calculation of the interface (I) modeled in step (a) using an interatomic potential; or b'i) obtain a Moiré pattern of the interface (I) modeled during step a); or b”i) perform an initial calculation of a structure of the interface (I) modeled during step a); steps bj, b'i) and b” J being implemented by means of a computer.

15. Method according to one of claims 1 to 14, in which step a) comprises a step ai) constructing crystal meshes of the crystal (1) on crystal meshes of the crystalline substrate (2); step ai) being implemented by means of a computer.

Images