Manufacturing method for single crystal diamond plate, single crystal diamond plate and large single crystal diamond wafer

Abstract

The present invention relates to a method (100) for producing a single crystal diamond plate from a plurality of single crystal diamond seeds (10, 11, 12, 13) comprising growth surfaces, the growth surfaces comprising terrace structures, the terrace structures having a plurality of crystal orientation planes (OC1, OC2), the crystal orientation planes (OC1, OC2) comprising a family of {100} planes or a family of {100} and {113} planes, the method comprising the following steps: providing (110) the single crystal diamond seeds (10, 11, 12, 13); arranging (130) the single crystal diamond seeds (10, 11, 12, 13) in a mosaic configuration; and performing lateral epitaxial overgrowth (140) of the terrace structures according to the crystal orientations (OC2).

Description

[Technical Field]

[0001] The present invention relates to the field of diamond production, and more particularly to the production of large single crystal diamonds. [Background technology]

[0002] The following describes the known prior art from which the present invention was developed.

[0003] Diamond is a material with physical properties that make it particularly valued in many fields. In particular, diamond has unparalleled properties as a semiconductor material, such as high thermal conductivity, high electron / hole mobility, high dielectric breakdown field strength, low dielectric loss, and wide band gap, radiation resistance, high chemical stability, and excellent optical properties.

[0004] Single crystal diamond remains one of the most promising materials for the fabrication of high power, high frequency, high temperature, high voltage, and quantum optoelectronic devices.

[0005] In particular, in order to put diamond to practical use as a semiconductor material, depending on the application, wafers made of single-crystal diamond with a large surface and high uniformity may be required.

[0006] Several growth methods have emerged to enable the formation of increasingly larger single crystal diamond wafers, among which the epitaxial step-flow growth method for producing single crystal diamond plates has made it possible to obtain single crystal diamond wafers of good quality.

[0007] Typically, large single-crystal diamond plates are produced by arranging multiple single-crystal diamond seeds in a mosaic pattern and growing them epitaxially by plasma-enhanced chemical vapor deposition (PECVD). Joints are formed between the seeds during epitaxial growth. The surface of the grown single-crystal diamond then needs to be polished to form a smooth surface before it can be used as a single-crystal diamond plate for growing single-crystal epitaxial layers.

[0008] The main technical difficulty relates to forming the junction between the seeds with few or no crystalline defects such as dislocations, twins, changes in the direction of wavefront propagation, etc. Indeed, the larger the size of the single crystal diamond plate, the more seeds are needed to form it, and the higher the risk of crystalline defects appearing at the junction.

[0009] The existence of these crystal defects is very serious because it not only affects the quality of the produced single crystal diamond, but also affects the polishing and cutting steps of the epitaxial layer formed on the growth surface. As a result, the joints of the single crystal become more brittle and may break more easily. Furthermore, the stress that often causes these crystal defects may cause breakage during the growth of the epitaxial layer.

[0010] Solutions aimed at partially resolving the above-mentioned problems have emerged. In particular, document WO2019139147 describes a method for producing single-crystal semiconductor substrates formed on large single-crystal diamond plates. The proposed solution limits the risk of breakage of the single-crystal diamond plate after cutting. To this end, it proposes using four 10 mm x 10 mm single-crystal diamond seeds with a crystal orientation of the family {100}, connected in a tessellated fashion. The plate formed by the single-crystal diamond seeds is recovered by a removal process using a "lift-off" method, i.e., removal of a sacrificial material. As a result, the processes of cutting and polishing the developed diamond plate are no longer necessary, thus limiting the risk of plate degradation during the polishing and cutting stages.

[0011] Another solution, described in document number CN114150376, proposes a method for splicing and growing large single-crystal diamonds with high crystalline quality at the splice junctions formed during the single-crystal diamond seed growth process. To this end, a single-crystal diamond epitaxial layer is formed on the surface of a single-crystal diamond seed with a {100} crystal orientation by chemical vapor deposition. The epitaxial layer is then recovered by laser cutting. This process is repeated to obtain multiple epitaxial layers with exactly the same crystal orientation. The epitaxial layers are then polished to reduce the difference in their heights. Next, a step-flow growth direction on the surface of the epitaxial layer is determined, and the epitaxial layer is aligned parallel to the step-flow growth direction and used as a seed for growing a single-crystal diamond epitaxial layer by chemical vapor deposition. In this way, a large single-crystal diamond epitaxial wafer is obtained.

[0012] Although it is possible to obtain thick diamond layers from seeds of the {100} family crystal orientation by plasma-enhanced chemical vapor deposition, which allows the production of single-crystal diamond mosaics with good joints, these methods do not allow the production of single-crystal diamond plates large enough to form substrates for electronic applications. Furthermore, the solutions proposed in the prior art involve the application of rather restrictive growth conditions, forcing relatively low growth rates and preventing the introduction of impurities by doping, which would alter the properties of the single-crystal diamond plate.

[0013] Therefore, there is a need to provide single crystal diamond plates with increased growth surface and improved quality.

[0014] The object of the present invention is to overcome the drawbacks of the prior art, and in particular to propose a method for manufacturing large single crystal diamond plates that makes it possible to ensure the formation of high-quality bonds between the seeds of single crystal diamond, i.e. bonds with few or no crystal defects. Summary of the Invention

[0015] The present invention is directed to overcoming these shortcomings. The following presents a simplified summary of selected aspects, embodiments, and examples of the invention in order to provide a basic understanding of the invention. However, this summary is not an exhaustive overview of all aspects, embodiments, and examples of the invention. Its sole purpose is to present selected aspects, embodiments, and examples of the invention in a simplified form as a prelude to the more detailed description of the aspects, embodiments, and examples of the invention that follows the summary.

[0016] The present invention particularly relates to a method for producing a single crystal diamond plate from a plurality of single crystal diamond seeds comprising growth surfaces, said growth surfaces comprising a terrace structure, said terrace structure having a plurality of crystal orientation planes, said crystal orientation planes comprising a family of {100} planes or a family of {100} and {113} planes, the method comprising the steps of: - providing single crystal diamond seeds, each of the seeds being associated with structural characteristics, said structural characteristics being at least a first value representing an angle indicating the direction of propagation of the wavefront, ○ Misorientation angle of terrace structure between 0° and 10° and - arranging the single crystal diamond seeds in a mosaic pattern, wherein two adjacent single crystal diamond seeds have a first value representing an angle indicative of the direction of propagation of the wavefront, the difference between which is no more than 5°, preferably no more than 1°; - performing lateral epitaxial growth of the terrace structure by enhanced chemical vapor deposition of a monocrystalline layer, preferably by plasma or hot filament deposition; Includes.

[0017] This therefore allows for the use of a larger number of single crystal diamond seeds, thereby increasing the available growth surface of the single crystal diamond plate from which single crystal diamond wafers can be produced, compared to prior art methods. In particular, the lateral epitaxial growth of the terrace structure is carried out according to crystal orientations including the {100} and {113} families of planes, preferably crystal orientations that form the step heights of the terrace structure. This lateral epitaxial growth allows for the formation of junctions between the seeds.

[0018] Moreover, such a method allows faster growth than that permitted by prior art methods while maintaining optimal crystal quality. The method according to the invention also makes use of a doping gas followed by irradiation, for example with an electron current, and in particular the central NV and NV - or XV and XV - It is also possible to modify the physical properties of the single crystal diamond or the surface of the single crystal diamond by the incorporation of X, where X is an element such as nitrogen N or silicon Si, for example.

[0019] It is a further object of the present invention to provide a large single crystal diamond plate having a larger growth surface than permitted by prior art methods and having optimum crystalline quality with few or no crystalline defects.

[0020] As will be shown below, the method according to the invention can be effective even if, during the seed placement step, two adjacent single crystal diamond seeds have a first value representing an angle indicative of the propagation direction of the wavefront, the difference between which is greater than 0°.

[0021] According to other optional features of the method for manufacturing a single crystal diamond plate, the latter may optionally include one or more of the following features, alone or in combination: - the step of lateral epitaxial growth is followed by a second vertical epitaxial growth in a stepped structure according to the crystal orientation of the {100} family of planes to form a monocrystalline diamond epitaxial layer, in particular a step of lateral epitaxial growth according to the crystal orientation of a monocrystalline diamond seed comprising the {100} family of planes or a monocrystalline diamond seed comprising the families of planes {100} and {113}, followed by a second vertical epitaxial growth. A first value, representing an angle indicating the direction of propagation of the wave front of the single crystal diamond seed, corresponds to the angle formed between the direction of propagation of the wave front and a side surface of the single crystal diamond seed. A first value, representing an angle indicating the propagation direction of the wavefront of the single crystal diamond seed, corresponds to a vector characteristic of the propagation direction of the wavefront relative to a side surface of the single crystal diamond seed. - calculating a second value representing an angle indicating the direction of propagation of the main wavefront of a plurality of single crystal diamond seeds from a first value representing the direction of propagation for each single crystal diamond seed, wherein during the step of arranging the single crystal diamond seeds in a mosaic, each single crystal diamond seed (10, 11, 12, 13) is arranged to have an angle of -5° to +5°, preferably -2.5° to +2.5°, relative to the second value. 10 ,FO 11) propagation direction (D 10 , D 11 ) includes the angle. - the method comprises a step of surface finishing the crystal orientation faces of a single crystal diamond seed by lithography or laser, so that the seeds have angles that indicate substantially identical wavefront propagation directions. In particular, the surface finishing step relates to the crystal orientation faces (OC1, OC2) of a single crystal diamond seed comprising the family of {100} faces or of a single crystal diamond seed comprising the families of {100} and {113} faces (10, 11, 12, 13). Preferably, the surface finishing step is carried out by laser. - the method includes a step of laser or lithographically refinishing the surface of the single crystal diamond plate after removal of the single crystal diamond epitaxial layer, the refinishing step comprising: Removal of a predetermined thickness of a single crystal diamond plate, Formation of predetermined new terrace structures having crystal orientation planes of a single crystal diamond seed including the family of {100} planes or crystal orientation planes of a single crystal diamond seed including the family of {100} and {113} planes Preferably, the re-surfacing step is performed by a laser. More preferably, the re-surfacing step involves the formation of a new structure with predetermined terraces having crystallographic orientation faces of the single crystal diamond seed comprising the {100} and {113} families of facets. This new terrace structure is preferably created on the single crystal diamond plate on the surface created during the removal step. The seeds of the new terrace structure are formed during a resurfacing process by laser or lithography and have angles that point to substantially the same wavefront propagation direction. The lateral epitaxial growth of the terrace structure following the crystallographic orientation of the monocrystalline diamond seeds comprises the introduction of a suitable gas to prevent the generation of stresses or the formation of crystal defects, preferably twins and dislocations, at the interface between the seeds. The terrace structure includes macroscopic growth steps. In particular, the terrace structure of the single crystal diamond seed can include growth steps with a height of, for example, at least 100 nm. This improves the properties of the bond and the resulting diamond layer. Furthermore, the macroscopic growth terraces can have a length L of at least 10 μm. 10 , L 11 It has. The method includes the step of creating a central portion "XV-" by doping with an appropriate gas "X" followed by electron beam irradiation and annealing, preferably after the lateral epitaxial growth step and / or the vertical epitaxial growth step. The step of positioning further comprises positioning the single crystal diamond seed at a distance of at most 200 μm relative to another single crystal diamond seed. The terrace structure of the single crystal diamond seed has a first planar misorientation along a horizontal axis and a second planar misorientation along a vertical axis that are less than 3° apart relative to each other. - each single crystal diamond seed has a thickness difference from another adjacent single crystal diamond seed of at most 50 μm, preferably at most 30 μm, however, a single crystal diamond seed may have a thickness difference from another adjacent single crystal diamond seed of at least 10 μm, for example at least 20 μm; - the single crystal diamond seeds are arranged in order of increasing thickness according to the propagation direction defined by one of the angles of the wavefront, so that the mosaic may include seeds with a thickness difference of at least 30 μm, for example at least 50 μm; The single crystal diamond seeds are arranged in order of decreasing thickness according to the propagation direction defined by one of the angles of the wavefront.

[0022] According to a second object, the present invention relates to a single crystal diamond plate comprising a plurality of single crystal diamond seeds comprising growth surfaces, said growth surfaces comprising a terrace structure, said terrace structure having a plurality of crystal orientation planes, said crystal orientation planes comprising a family of {100} planes or a family of {100} and {113} planes, a misorientation angle of the terrace structure being between 0° and 10°, and a single crystal joint connecting the single crystal diamond seeds - arranging the single crystal diamond seeds in a mosaic pattern, wherein two adjacent single crystal diamond seeds have a first value representing an angle indicative of the direction of propagation of the wavefront, the difference between which is less than or equal to 5°, preferably substantially equal to 0°; - performing lateral epitaxial growth of the terrace structure according to the crystal orientation by enhanced chemical vapor deposition of a monocrystalline layer, preferably by plasma or hot filament deposition; is obtained by

[0023] Similarly, a diamond plate according to the present invention will have the expected properties even if two adjacent single crystal diamond seeds have a first value representing the angle indicating the direction of propagation of the wavefront, the difference between which is greater than 0°.

[0024] Among other optional characteristics of the single crystal diamond plate, the latter may optionally include one or more of the following characteristics, alone or in combination: - at least 15%, preferably at least 50%, more preferably at least 85% of the joints formed between the single crystal diamond seeds have a Raman peak width at half height value of 2.5 cm -1 Over 2.9cm -1 is less than.

[0025] According to a third object, the present invention relates to a single crystal diamond wafer formed by removing the single crystal diamond epitaxial layer obtained by the method according to the present invention.

[0026] According to another aspect, the present invention also relates to a single crystal diamond having a surface including at least a first crystal face and a second crystal face, each of which is associated with a concentration of the central "XV-" element, the concentration of the central "XV-" element in the first crystal face being greater than the concentration of the central "XV-" element in the second crystal face. In particular, in the single crystal diamond according to the present invention, the first crystal face of the single crystal diamond belongs to the family of planes {113}. As will be described later, such a single crystal diamond can be obtained by the method according to the present invention.

[0027] According to a fourth object, the present invention relates to the use of a single crystal diamond plate according to the present invention, a single crystal diamond according to the present invention or a single crystal diamond wafer according to the present invention for the production of optical windows, substrates for semiconductors, substrates for thermal management, substrates for quantum technology or diamonds for gemstones, preferably diamonds larger than 5 carats, preferably larger than 15 carats. [Brief explanation of the drawings]

[0028] Other characteristics and advantages of the invention will be better understood on reading the following description and on referring to the accompanying drawings, which are given by way of example and not of limitation, and in which: FIG.

[0029] [Figure 1] Figure 1 shows a diagram of a method for manufacturing a single crystal diamond plate according to the present invention. Steps enclosed in dotted lines are optional. [Figure 2] FIG. 2 shows a cross-sectional view of a single crystal diamond seed from the side. [Figure 3] FIG. 3 shows a cross-sectional view of the single crystal diamond plate after growth of the single crystal diamond layer as viewed from the side. [Figure 4] FIG. 4 shows a first view of the cross section of two single crystal diamond seeds as viewed from the side. [Figure 5] FIG. 5 shows a perspective view of a single crystal diamond seed. [Figure 6]Figure 6 shows a top view of a single crystal diamond seed, whose step flow occurs along OC2, which belongs to either a) the family of planes {113} or b) the family {100}. [Figure 7] Figure 7 shows a top view of a mosaic containing nine single crystal diamond seeds. [Figure 8] Figure 8 shows a top view of four single crystal diamond seeds. [Figure 9] FIG. 9 shows a second view of the cross section of two single crystal diamond seeds from the side. [Figure 10] FIG. 10 corresponds to a photograph of a portion of a single crystal diamond plate according to the invention seen from above.

[0030] The figures are for illustrative purposes and are not necessarily drawn to scale, particularly with regard to thickness.

[0031] Aspects of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods according to embodiments of the invention.

[0032] In the figures, flowcharts and block diagrams illustrate the structure, functionality, and operation of possible implementations of systems and methods according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a system, device, module, or code that includes one or more executable instructions for implementing one or more specified logical functions. In some implementations, the functions associated with the blocks may occur in a different order than that shown in the figures. For example, two blocks shown in succession may, in fact, be performed substantially simultaneously, or the blocks may sometimes be performed in the reverse order, depending on the functionality involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a specific hardware system that performs the specified functions or acts or a combination of specific apparatus and computer instructions. DETAILED DESCRIPTION OF THE INVENTION

[0033] The following provides an overview of the invention and related terms, then presents shortcomings of the prior art, and finally describes in more detail how the present invention overcomes them.

[0034] In the remainder of this specification, the expression "single crystal diamond plate" may correspond to at least two single crystal diamond seeds that are joined together after the first crystal growth.

[0035] The expression "large" in the sense of the present invention means a growth surface of 2 cm 2 More than 3cm, preferably 2 More than 5cm, preferably 2 More than 10cm, more preferably 2 More than 20cm, preferably 2 More than 315cm, preferably 2 This may correspond to more than one plate or wafer.

[0036] The term "seed" in the sense of the present invention can correspond to the element on which the diamond layer or film is grown. In the case of single crystal layers, these are natural diamond single crystals, or are produced by the high pressure, high temperature (HPHT) method, or by a CVD (chemical vapor deposition, or plasma or hot filament enhanced chemical vapor deposition) process.

[0037] The term "junction" can refer to the part that physically connects two species together.

[0038] When the term "family of crystallographic orientation planes" is used, it usually refers to a family of crystallographic planes. Crystallographic planes whose surfaces are substantially flat and have a particular crystallographic morphology that constrains the crystal are conventionally displayed between curly brackets. This includes all variations in position that a crystallographic orientation plane can assume within a crystal. As an example, the family of crystallographic orientation planes in the family {100} also includes positive and negative variations, such as crystallographic planes (010) and (001); similarly, the family of crystallographic orientation planes in the family {113} includes positive and negative variations, such as crystallographic planes (131) and (311). These crystallographic planes are usually defined by three Miller indices "(hkl)" shown between brackets, where h, k, and l may be positive or negative integers.

[0039] A "terrace structure" according to the present invention may correspond to a stepped structure including steps characterized by a first crystal orientation and terraces characterized by a second crystal orientation. The second crystal orientation is preferably different from the first crystal orientation. The steps of the terrace structure are substantially linear and parallel to one another. The terraces are substantially linear and parallel to one another. As an illustrative example, the terraces are formed by crystal orientation planes of the {100} family of planes, and the steps are formed by crystal orientation planes of the {113} family of planes of the terrace structure. They may, for example, form an angle of 154.8° or 107.5° between them.

[0040] The term "growth" in the sense of the present invention may correspond to one or more steps of depositing carbon in the sp3 form of crystalline (single crystal) diamond that contributes to the production of a single crystal diamond layer. The growth conditions and deposition parameters represent a set of variable values: pressure, injected microwave power, total gas flow rate, carbon precursor flow rate, impurity and dopant flow rates, thermal resistance gas composition and their flow rates, temperature of the growth layer or layers in a given reactor.

[0041] The term "diamond" in the sense of the present invention may correspond to one or more monocrystalline diamond layers of different thickness resulting from the deposition of carbon in the sp3 form on crystalline (monocrystalline) diamond.

[0042] The expression "diamond layer" in the sense of the present invention can correspond to a layer (or film) of single-crystal, polycrystalline, nanocrystalline or ultrananocrystalline diamond formed after nucleation on the surface of a single-crystal diamond or other material. In the sense of the present invention, the production of single-crystal diamond is generally carried out by thickening the height and / or width of a strained (or seed) diamond single crystal, which originates from a single crystal of natural diamond, or is produced by the high-pressure, high-temperature (HPHT) method, or is produced by CVD (plasma or hot filament enhanced "chemical vapor deposition").

[0043] The term "plasma" in the sense of the present invention may correspond to the production of a medium that is electrically neutral overall but contains ions and electrons, as well as fragments of dissociated gas species and stable molecules, from an electrical discharge in a gas mixture.

[0044] In the sense of the present invention, the expression "terrace structure misorientation" (denoted δ) may correspond to the presence of an orientation angle characterizing the inclination of the terrace structure, more specifically the inclination of the terraces formed by the crystal orientation planes, for example of the family of faces {100}, relative to the rear face of the single crystal diamond seed.

[0045] The term "substantially" in the sense of the present invention means a value that varies by less than 30%, preferably less than 20%, and more preferably less than 10% from the comparison value. When "substantially the same" is used for comparing shapes, the vectorized shape varies by less than 30%, preferably less than 20%, and more preferably less than 10% from the vectorized shape being compared. In particular, when "substantially the same" is used for comparing angles, the angle value does not differ by more than 10°, preferably by more than 5°, more preferably by more than 2°, and more preferably by more than 1°.

[0046] Many industrial applications expect large single crystal diamond layers (e.g., greater than 20 centimeters in diameter). Many methods have already been proposed for producing large single crystal diamond layers. However, the single crystal diamonds obtained by these methods usually have crystal defects as their size increases. The applicant has developed a new method that can reduce these crystal defects.

[0047] The applicant proposes to use single crystal diamond seeds with crystal orientation planes of the {100} family of planes, preferably the {100} and {113} families of planes, to produce high-quality, large single crystal diamond plates by taking into account the structural characteristics of each seed and arranging them at the propagation angle of the wavefront. This allows for the formation of high-quality joints, i.e., joints with few or no crystal defects between the single crystal diamond seeds. In particular, the invention proposes that the first growth be produced under conditions favorable for the lateral growth of crystal orientation planes of the {113} family of planes, ensuring the formation of a single crystal layer of optimal quality between the seeds, thereby limiting the risk of crystal defect formation and cracking during the growth or cutting of the single crystal diamond wafer.

[0048] Thus, as shown in Figure 1, the present invention relates to a method 100 for producing a large single crystal diamond plate from a plurality of single crystal diamond seeds, the method comprising a step 110 of providing single crystal diamond seeds having related structural properties, a step 130 of arranging the single crystal diamond seeds, and a step 140 of lateral epitaxial growth.

[0049] The single crystal diamond seed 10 is shown in Figure 2. The single crystal diamond seed 10, and more generally the single crystal diamond seeds 11, 12, 13 according to the invention, has at least one face F which constitutes the growth plane of the crystal. SC This plane is composed of a crystal plane formed by crystal orientation planes OC1 and OC2, which are terraces and steps of the terrace structure, respectively. The seed also includes a plane F that constitutes the growth plane of the crystal.SC The rear face F on the opposite side of AR , on which the aforementioned seeds 10 are located during the growth process. SC Terrace OC1 front and rear F AR are substantially parallel, but they have an angle d between them. 10 This is called the misazimuth angle.

[0050] Thus, as shown in detail in Figure 3, the single crystal diamond seed 10 includes a stepped or stepped structure on its surface having crystal orientation planes OC1, OC2 in the family of planes {100} or the family of planes {100} and {113}. As shown in Figure 4, the terrace structure of the single crystal diamond seeds 10, 11 includes crystal orientation planes OC1 and OC2 with predetermined surfaces. More specifically, the terrace structure of the single crystal diamond seeds 10, 11 includes crystal orientation planes OC1 and OC2 with predetermined surfaces. 10 , L 11 and height H 10 , H 11 Indeed, as shown in Figure 4, the terrace structures of the single crystal diamond seeds 10, 11 used to form the single crystal diamond plate preferably have substantially identical or at least relatively similar misorientation angles δ 10 , δ 11 , which may be, for example, 0° to 10°.

[0051] Azimuth angle δ 10 , δ 11 is, for example, at least 0.1°, preferably at least 0.5°, more preferably at least 1°, and even more preferably at least 2°. 10 , δ 11 is, for example, at most 9.9°, preferably at most 9.5°, more preferably at most 9°, and even more preferably at most 8°. 10 , δ 11 is, for example, 0.1° to 9.9°, preferably 0.5° to 9.5°, more preferably 1° to 9°, and even more preferably 2° to 8°.

[0052] As mentioned above, different misorientation angles can be observed within the same seed.Advantageously, the misorientation angles within the same seed should not be significantly different.Therefore, preferably, the single crystal diamond seeds used in the context of the present invention will have a misorientation angle difference of at most 10%, more preferably at most 5%, and even more preferably at most 1%.

[0053] More specifically, as shown in FIGS. 4 and 5, the terrace structure of the single crystal diamond seed may have a height H 10 , H 11 may contain macroscopic growth steps of at least 100 nm and up to 5 μm.

[0054] The terrace structure of the single crystal diamond seed may include growth steps having a height of, for example, at least 100 nm, preferably at least 200 nm, more preferably at least 500 nm, and even more preferably at least 1000 nm. The height of the growth steps may be, for example, at most 4.5 μm, preferably at most 4 μm, more preferably at most 3.5 μm, and even more preferably at most 3 μm. Thus, the height of the growth steps may be, for example, 100 nm to 4.5 μm, preferably 200 nm to 4 μm, more preferably 500 nm to 3.5 μm, and even more preferably 1000 nm to 3 μm. The height of the growth steps may vary within a seed. Therefore, the above values ​​may correspond to the median values ​​observed within the seed.

[0055] Preferably, single crystal diamond seeds used in the context of the present invention have growth step height differences of less than 30%, more preferably less than 20%, even more preferably less than 10%.

[0056] Furthermore, the macroscopic growth terrace OC1 has a length L of 10 μm to 300 μm. 10 , L 11 It may have.

[0057] The terrace structure of the single crystal diamond seed may include growth terraces, for example, having lengths of at least 10 μm, preferably at least 20 μm, more preferably at least 30 μm, and even more preferably at least 50 μm. The length of the growth terraces may be, for example, at most 300 μm, preferably at most 250 μm, more preferably at most 200 μm, and even more preferably at most 150 μm. Thus, the length of the growth terraces may be, for example, 10 μm to 300 μm, preferably 20 μm to 250 μm, more preferably 30 μm to 200 μm, and even more preferably 50 μm to 150 μm. The length of the growth terraces may vary. Thus, the above values ​​may correspond to the median values ​​observed for the seeds.

[0058] Preferably, single crystal diamond seeds used in the context of the present invention have growth terrace lengths that vary by less than 30%, more preferably less than 20%, and even more preferably less than 10%.

[0059] The method according to the invention therefore comprises a step 110 of providing single crystal diamond seeds 10, 11, 12, 13, each of which is associated with a structural characteristic. In the context of the present invention, the structural characteristic is the wavefront FO 10 Propagation direction D 10 The angle includes at least a first value representing an angle indicating

[0060] Such an angle is determined by the side F of the single crystal diamond seed 10 oriented as shown in FIGS. BD The angle D can be formed by the step or the crystal orientation plane OC2 and the direction of movement of the axis x or y. 10 The value of the wavefront FO 10 It is possible to define a propagation direction of , which represents the movement of a step plane or crystal orientation plane OC2, called a wave front, as shown in FIG.

[0061] The method according to the present invention may further comprise the step (not shown) of determining the structural properties of each of the single crystal diamond seeds 10, 11, 12, 13 mentioned above.

[0062] As shown in Figure 7, for each species, the wavefront FO 10 Angle D indicating the direction of propagation of 10 , D 11 A first value is provided that represents the angle D 10 , D 11 are defined so that they belong to the interval [0, π / 2]. During diamond growth by microwave plasma-enhanced deposition, the wave fronts move at very specific angles, senses, and directions along the terrace structure of each single crystal diamond seed.

[0063] In addition, the structural characteristics are rear F AR The misorientation angle δ of the terrace structure is between 0° and 10° with respect to the surface of the substrate. Advantageously, the misorientation angle is strictly greater than 0°. Furthermore, when the misorientation angle is greater than 0° and less than or equal to 10°, growth by a step flow mechanism occurs, which makes it possible to limit the appearance of crystal defects, in particular the formation of twins, during the growth phase.

[0064] In addition, the structural characteristics may include the dimensions of the growth steps of the terrace structure, the propagation direction of the wavefront, and / or the thickness of each single crystal diamond seed 10, 11, 12, 13.

[0065] Known techniques can be used to determine the structural properties of the single crystal diamond seeds 10, 11, 12, 13, such as electron backscatter diffraction, which allows for microstructural and crystallographic characterization by optical or digital microscopy, scanning electron microscopy, etc. This provides information about the structure, crystallographic orientation, phase, or strain of the material.

[0066] Furthermore, it is possible to measure the crystal orientation of the seed faces by electron microscopy techniques and provide only seeds having faces with the same crystal orientation.

[0067] The manufacturing method 100 also includes a step of forming a diamond crystal in a propagation direction D 10 , D 11The method may also include a step 120 of calculating a second value representing an angle indicative of the propagation direction of the main wavefront FO of the plurality of single crystal diamond seeds 10, 11, 12, 13 from the value representing the angle indicative of

[0068] As a non-limiting example, the computing step 120 can be performed by a computer, or more generally by any type of computing device configured for this purpose.

[0069] In a first embodiment, the manufacturing method 100 according to the invention may comprise a step 115 of lithographically and / or laser finishing the surfaces of the crystal orientation planes OC1, OC2 of the family of faces {100} or of the families of faces {100} and {113} of the monocrystalline diamond seeds 10, 11, 12, 13, so that said seeds have a wavefront FO 10 ,FO 11 Propagation direction D 10 , D 11 This therefore makes it possible to limit the appearance of crystal defects during the growth stage.

[0070] As a non-limiting example, the surface finishing step 115 can be performed by a laser, such as a water jet, e.g., a laser guided by a 50 μm diameter, 532 nm wavelength, 50 W power, and 6 kHz frequency. In particular, the surface finishing step 115 can be performed by a laser having a diameter of at least 10 μm, preferably at least 20 μm, more preferably at least 30 μm, and even more preferably at least 50 μm. The surface finishing step 115 can be performed by a laser having a diameter of at most 200 μm, preferably at most 150 μm, more preferably at most 125 μm, and even more preferably at most 100 μm.

[0071] The surface finishing step 115 can be performed by scanning a laser over the surface of the single-crystal diamond plate. Alternatively, the surface finishing step 115 can be performed by lithography, specifically by using a photolithography mask containing a pattern to be generated on the surface of the diamond. Prior to photolithography, there is a step of depositing SiO2 in a PECVD (plasma-enhanced chemical vapor deposition) frame, followed by a step of depositing a photosensitive resin. The next step of depositing SiO2 and thus etching the diamond in a reactive ion etching frame allows for another surface finishing to be completed.

[0072] The manufacturing method 100 according to the present invention further includes a step 130 of arranging the single crystal diamond seeds in a mosaic pattern. The single crystal diamond seeds are arranged such that two adjacent single crystal diamond seeds have a wavefront FO 10 ,FO 11 Propagation direction D 10 , D 11 and the difference is preferably substantially equal to 0°, more preferably equal to 0°.

[0073] The single crystal diamond seeds are arranged such that two adjacent single crystal diamond seeds are aligned in a wavefront 10 ,FO 11 Propagation direction D 10 , D 11 and the difference between the first and second values ​​is at most 5°.

[0074] The single crystal diamond seeds are arranged such that two adjacent single crystal diamond seeds are aligned in a wavefront 10 ,FO 11 Propagation direction D 10 , D 11 and the difference is between 0° and 5°.

[0075] The single crystal diamond seeds are arranged such that two adjacent single crystal diamond seeds are aligned in a wavefront 10 ,FO 11Propagation direction D 10 , D 11 and may be arranged such that the difference is not more than 4°, preferably not more than 3°, preferably not more than 2°, more preferably not more than 1°, and more preferably equal to 0°.

[0076] In one embodiment, the single crystal diamond seed arrangement 130 is arranged in a wavefront FO to form a mosaic. 10 ,FO 11 and each single crystal diamond seed 10, 11, 12, 13 is propagated in the same direction of wavefront F0. 10 ,FO 11 Propagation direction D 10 , D 11 and the difference is between 0° and 5° and with respect to a second value representing the angle indicating the propagation direction of the main wavefront FO of the plurality of single crystal diamond seeds 10, 11, 12, 13 that make up the mosaic.

[0077] Optionally, as shown in Figure 7, the single crystal diamond seeds 10, 11, 12, and 13 may be parallelepiped-shaped, more specifically square-shaped, or even octahedral or triangular-shaped. Furthermore, they may be arranged offset from one another, so that at least one vertex S of each single crystal diamond seed 10, 11, 12, and 13 is located opposite the side of the adjacent single crystal diamond seed. Therefore, the vertices S of the seeds face each other, with or without contact with a maximum of two adjacent seeds. This makes it possible to limit the occurrence of mechanical stress during the growth stage.

[0078] In order to obtain a high quality joint and to enable the production of large single crystal diamond plates, the single crystal diamond seed may have a thickness difference of up to 50 μm, preferably up to 30 μm, compared to another adjacent single crystal diamond seed.

[0079] To further improve the formation of high quality joints and enable the production of large single crystal diamond plates, the single crystal diamond seed is formed using a wavefront FO 10 ,FO 11 Angle D 10 , D 11 More specifically, the single crystal diamond seeds can be arranged in order of increasing thickness according to a propagation direction defined by one of the angles D 10 , D 11 The wavefront FO is given by 10 ,FO 11 As an example to aid in understanding, a mosaic may be formed by placing a single crystal diamond seed having a first minimum thickness E1 at an associated angle D 10 , D 11 Then, a single crystal diamond seed having a second thickness E2 that increases with respect to the first thickness E1 by less than 5 μm can be placed adjacent to the single crystal diamond seed having such first thickness E1. Finally, a single crystal diamond seed having a third thickness E3 of increasing thickness, for example, a thickness greater than 5 μm and up to 50 μm different from the adjacent seed, can then be placed adjacent to the wavefront FO 10 ,FO 11 Angle D 10 , D 11 and the second single crystal diamond seed has a second thickness E2 that increases with respect to the first thickness E1 by less than 5 μm in a direction of propagation defined by one of: Accordingly, the difference in thickness between each adjacent single crystal diamond seed is preferably 30 μm or less, more preferably 25 μm or less, even more preferably 20 μm or less, for example 15 μm or less.

[0080] Optionally, the positioning step 130 may further comprise positioning the single crystal diamond seed relative to another single crystal diamond seed at a distance R1 of at most 200 μm, preferably at most 150 μm, more preferably at most 100 μm, and even more preferably at most 50 μm.

[0081] Further in accordance with the present invention, a method 100 for producing a large single crystal diamond plate includes depositing a single crystal diamond layer on a mosaic, the deposition step including one or more epitaxial growth steps. Depositing the single crystal diamond layer on the mosaic can include injection of gases under predetermined pressure, flow rate, and temperature conditions. To this end, the mosaic is placed, for example, in a microwave plasma-enhanced deposition reactor of known type, for example, under conditions of 200 mbar, 21 kW, 2000 sccm H2, 5% CH4, and a growth temperature in the range of 1000°C to 1060°C. By way of non-limiting example, the microwave plasma-enhanced deposition reactor can include: - a resonant cavity defined at least in part by the cylindrical inner wall of the reactor housing; - a process gas supply system capable of providing a process gas into the resonant cavity; - a microwave generator configured to generate microwaves having a frequency between 300 MHz and 3000 MHz; - a gas exhaust module capable of removing said gas from the resonant cavity; - a wave coupling module capable of transmitting microwaves from a microwave generator to a resonant cavity so as to form a uniform plasma at the plasma / surface interface; - a growth support present within the resonant cavity; - Surface growth temperature control module.

[0082] In particular, the manufacturing method 100 according to the invention comprises a step 140 of carrying out lateral epitaxial growth of a terraced structure by plasma enhanced chemical vapor deposition of a monocrystalline layer according to the crystal orientation OC2 of the planes of the family of planes {100} if the seeds only comprise the family of planes {100}, or according to the crystal orientation OC2 of the planes of the family of planes {113} if the seeds comprise the families of planes {100} and {113}.

[0083] The lateral epitaxial growth step 140 may be carried out in a plasma-enhanced deposition reactor of known type at predetermined conditions to allow growth C2 according to the crystal orientation OC2, as shown in FIG.

[0084] Preferably, the epitaxial growth step 140 involves epitaxial growth according to the crystal orientation OC2 of a plane of the {113} family of planes, which in fact allows the formation of a single crystal junction 10-1 between two high quality single crystal diamond seeds 10, 11, as shown in the examples.

[0085] The lateral epitaxial growth step 140 can optionally be performed by means suitable for hot-wire enhanced chemical vapor deposition.

[0086] As an example to aid in understanding, the growth conditions during the lateral epitaxial growth step 140 may include the creation of a pressure in the resonant cavity of 20 hPa to 500 hPa, a power of, for example, 0.5 kW to 100 kW (or more), depending on the type of generator used (frequency used), e.g., at least 150 standard cm 3 Injection of gases at a total flow rate of 1000 nm per minute (sccm), such as methane, argon, and dihydrogen, or mixtures of all or part of these gases, and additives such as oxygen, nitrogen, boron, phosphorus, and argon, or halogens, and operation of a cooling system for the enclosure, substrate, gas injection system, and substrate holder to control the temperature of one or more growth surfaces, preferably in the range of 800°C to 1200°C.

[0087] In a specific embodiment of the manufacturing method 100 according to the present invention, the lateral epitaxial growth step 140 of the terrace structure according to the crystal orientation OC2 of the single crystal diamond seeds 10, 11, 12, 13 comprising the family of {100} planes or the single crystal diamond seeds 10, 11, 12, 13 comprising the family of {100} and {113} planes can include a step 141 of introducing a suitable gas to prevent the generation of stress and the formation of twins at the interface between the seeds 10, 11, 12, 13. Such a gas can be introduced, for example, by a gas supply system, and allows the supply of nitrogen into the resonant cavity, for example, at a nitrogen concentration of at most 250 ppm, preferably at most 10 ppm, preferably at most 3 ppm. For example, using nitrogen with a content of at least 1 ppm during the lateral epitaxial growth step 140 can limit the generation of crystal defects, especially twins, and ensure higher crystal stability.

[0088] In a specific embodiment of the manufacturing method according to the present invention, the lateral epitaxial growth step 140 can further include step 142, which creates a colored center portion, referred to as "XV-," followed by electron beam irradiation and annealing. To this end, step 142, which creates the center portion XV-, involves the introduction of a doping gas "X," such as, but not limited to, nitrogen or silicon, into the resonant cavity via a gas supply system, for example, at a nitrogen concentration of 10 ppm to 1000 ppm. The use of such so-called doping gases allows for the modification of the properties of the synthetic diamond. This can, for example, modify its optical, electronic, and quantum properties. Advantageously, the creation step 142 can be performed during lateral epitaxial growth of a terrace structure according to the crystal orientation OC2 of a plane of the {113} family of planes.

[0089] In another particular embodiment of the manufacturing method according to the invention, the latter may comprise a second step of lateral epitaxial growth, as described above, further including the creation of a central "XV-" portion 142. Preferably, this step of creating the central "XV-" portion 142 will be performed after a surface polishing step.

[0090] In the manufacturing method 100 according to the present invention, the terraced lateral epitaxial growth step 140, which allows for the formation of a junction by lateral movement of the planes OC2, can be followed by a second vertical epitaxial growth 150 according to the crystal orientation OC1 of the planes of the family of {100} planes of the single crystal diamond seeds 10, 11, 12, 13 comprising the family of planes {100} or the single crystal diamond seeds 10, 11, 12, 13 comprising the families of planes {100} and {113}, thereby allowing for vertical growth to form the single crystal diamond epitaxial layer 10-2. The terraced vertical growth step 150 according to the crystal orientation OC1 of the family of planes {100} can be carried out in the microwave plasma enhanced deposition reactor described above under predetermined conditions for promoting growth C1 according to the crystal orientation OC1, as shown in Figure 3. The step flow growth mechanism (transfer of wave fronts from one seed to another) makes it possible to form a high quality single crystal junction 10-1 between two single crystal diamond seeds 10, 11. The vertical epitaxial growth step 150 according to the crystal orientation OC1 of the planes of the {100} family of planes also proceeds according to this mechanism, with the crystal growing according to C1 (vertical) and then according to C2 (lateral), but with the growth conditions adapted to promote either vertical or lateral growth, more pronounced according to the orientations OC1 and OC2.

[0091] If the manufacturing method 100 according to the invention includes a second vertical epitaxial growth 150, it may also require a step 160 of removing the single crystal diamond epitaxial layer 10-2. The removal step 160 may consist of cutting with a laser of known type, or another method, for example of the lift-off type.

[0092] As already mentioned, one of the objects of the present invention is to produce a single crystal diamond plate 1 having a high quality bond. Another object of the present invention is to enable the reuse of said single crystal diamond plate 1 once produced. For this purpose, the step 160 of removing the single crystal diamond epitaxial layer 10-2 can be followed by a step 115' of refinishing the surface of the single crystal diamond plate by laser or lithography. The step 115' of refinishing the surface by laser or lithography includes the following: - Removal of a predetermined thickness of a single crystal diamond plate; - optionally a polishing step; - forming a predetermined new terrace structure having crystal orientation planes OC1, OC2 of the single crystal diamond seeds 10, 11, 12, 13 comprising the family of planes {100}, or crystal orientation planes OC1, OC2 of the single crystal diamond seeds 10, 11, 12, 13 comprising the family of planes {100} and {113}, or crystal orientation planes OC1, OC2 of the single crystal diamond seeds 10, 11, 12, 13 comprising the family of planes {100} and {110}.

[0093] In order to maintain the same quality for the formation of the single crystal joint, the crystal orientations OC1, OC2 of the family of planes {100} or the family of planes {100} and {113} of the new terrace structure are aligned with the wavefronts FO of the single crystal diamond seeds of the placement step 130. 10 ,FO 11 Propagation direction D 10 , D 11 The angle is formed according to the angle shown.

[0094] Therefore, the seeds of the new terrace structure formed during the laser or lithographic resurfacing step 115' are substantially identical wavefronts FO 10 ,FO 11 Propagation direction D 10 , D 11 The angle indicates

[0095] As shown in Figures 8 and 9, the single crystal diamond seeds of the manufacturing method 100 according to the present invention may include terrace structures having planar misorientations along a horizontal axis Y1 and a vertical axis Z1 relative to each other.

[0096] The planar misorientation angle α along the horizontal axis Y1 and / or the vertical axis Z1 10 , α 11 , β 10 , β 11 each having a side F BD and / or face F constituting the rear face of the crystal AR , for example, less than 3°, preferably less than 2.5°, more preferably less than 2°, and even more preferably equal to 0°. The planar misorientation angle α 10 , α 11 each having a side F BD and / or face F constituting the rear face of the crystal AR The planar misorientation angle α along the horizontal axis Y1 and / or the vertical axis Z1 is, for example, 0° or more, preferably greater than 0.1°, more preferably greater than 0.2°, and even more preferably greater than 0.5°. 10 , α 11 each having a side F BD and / or face F constituting the rear face of the crystal AR , for example, 0° to 3°, preferably 0° to 2.5°, more preferably 0° to 1°, and even more preferably 0° to 0.5° (both inclusive). Alternatively, the plane misorientation has a plane misorientation degree along the horizontal axis Y1 and / or the vertical axis Z1, each of which is parallel to the side surface F BD and / or face F constituting the rear face of the crystal AR With respect to this, the angle may be, for example, 0.1° to 3°, preferably 0.2° to 2.5°, and more preferably 0.5° to 1°.

[0097] The planar misorientation angle may vary within a mosaic. Thus, the above values ​​of the planar misorientation angle may correspond to the median value observed for a species. Preferably, a mosaic used in the context of the present invention has a planar misorientation angle that varies by less than 30%, more preferably less than 20%, and even more preferably less than 10% relative to the median planar misorientation angle.

[0098] According to a second object, the invention relates to a preferably large single crystal diamond plate 1 obtainable by the invention. The single crystal diamond plate 1 can advantageously be obtained by a manufacturing method 100 according to the invention.

[0099] In particular, the present invention relates to a preferably large, single crystal diamond plate 1 comprising a growth surface, said growth surface comprising a terrace structure, said terrace structure having a plurality of crystal orientation planes OC1, OC2, said crystal orientation planes OC1, OC2 comprising a family of planes {100} or a family of planes {100} and {113}, the misorientation angle (δ) of the terrace structure being between 0° and 10°, and wherein the single crystal joints connecting the single crystal diamond seeds 10, 11, 12, 13 to one another are: - arranging the single crystal diamond seeds in a mosaic pattern, wherein two adjacent single crystal diamond seeds 10, 11, 12, 13 are arranged in a wavefront FO 10 ,FO 11 Propagation direction D 10 , D 11 a first value representing an angle indicating the difference between the first and second angles, the difference being 0° or more and 5° or less, preferably 1° or less; - performing lateral epitaxial growth of the terrace structure according to the crystal orientation OC2 by enhanced chemical vapor deposition of a monocrystalline layer, preferably by plasma or hot filament deposition; is obtained by

[0100] The single crystal diamond plate 1 according to the present invention comprises joints formed between single crystal diamond seeds, wherein at least 15%, preferably at least 50%, more preferably at least 85% of the joints have a width at half height of the Raman peak of less than 2.4 cm. -1 ~2.9cm -1 , preferably substantially 2.5 cm -1 is equal to.

[0101] The single crystal diamond plate 1 according to the present invention therefore allows for the formation of a single crystal diamond epitaxial layer 10-2 by growth according to the crystallographic orientation OC1 of the {100} plane. The quality of the bond in the single crystal diamond plate 1 allows for the epitaxial layer 10-2 to be removed to yield large single crystal diamond wafers, in particular suitable for use in the manufacture of optical windows, semiconductor substrates, thermal management substrates, substrates suitable for quantum technology, or gem diamonds at least larger than 5 carats, preferably larger than 10 carats, and preferably larger than 15 carats. Alternatively, the single crystal diamond plate 1 according to the present invention can be used directly for the above applications.

[0102] The present invention makes it possible to form a single crystal diamond (plate or wafer) having a surface including at least a first crystal face and a second crystal face, each of which is associated with a concentration of the central "XV-" element, with the concentration of the central "XV-" element in the first crystal face being greater than the concentration of the central "XV-" element in the second crystal face. Such single crystal diamonds have particularly promising properties. In fact, while many attempts to homogenize the concentration of the central "XV-" element on the surface of a single crystal diamond, the present invention focuses on the central "XV-" element and attempts to create regions of different concentrations. Furthermore, advantageously, the single crystal diamonds according to the present invention are large in size.

[0103] Preferably, the concentration of the central "XV-" in the crystal face is such that the ratio of the concentration of the central "XV-" in the first crystal face to the concentration of the central "XV-" in the second crystal face is greater than 1.1, preferably greater than 2, more preferably greater than 5, and even more preferably greater than 10. The concentration of the central "XV-" can be measured using several techniques, for example photoluminescence measurements by confocal microscopy coupled with Hanbury-Brown and Twiss interferometry (see Thesis L. Rondin, HAL Id: tel-00824468, 2013).

[0104] The concentration of the central "XV-" of the first crystal face is, for example, greater than 3 ppm, preferably greater than 5 ppm, and more preferably greater than 10 ppm.

[0105] Thus, the single crystal diamond plate or wafer may have a central "XV-" enriched band relative to adjacent single crystal diamond regions. Preferably, the single crystal diamond may comprise at least two bands at least 10 μm in height that have a greater concentration of central "XV-" than adjacent single crystal diamond regions.

[0106] These bands may correspond to a first crystallographic plane. Preferably, the single crystal diamond wafer may include at least two bands at least 10 μm in height corresponding to the first crystallographic plane.

[0107] Although the crystal faces may have the same crystallographic orientation (e.g., the {100} family of planes), the crystal faces preferably have crystallographic orientations of different plane families. Also, a single crystal diamond wafer may have bands corresponding to crystallographic orientation planes of a first family of planes and bands corresponding to crystallographic orientation planes of a second family of planes that are different from the first family of planes.

[0108] Preferably, the single crystal diamond may include at least two bands corresponding to crystal faces having a crystal orientation of a first family of faces and at least two bands corresponding to crystal faces having a crystal orientation of a second family of faces that is different from the first family of faces.

[0109] Furthermore, advantageously, the first crystallographic face may belong to the family of {113} or {110} faces, and the second crystallographic face may belong to the family of {100} faces.

[0110] Thus, single crystal diamonds may have bands distinguished by the concentration of central "XV-" and / or the family of crystallographic plane orientations.

[0111] Preferably, therefore, the present invention relates to a single crystal diamond (plate or wafer) having a surface comprising at least a first crystal face and a second crystal face, each of said crystal faces being associated with a concentration of the central "XV-" element, the concentration of the central "XV-" element of the first crystal face being greater than the concentration of the central "XV-" element of the second crystal face.

[0112] Such a single crystal diamond may have the properties described above in connection with the method, plate or wafer according to the invention. Advantageously, the first crystal face of the single crystal diamond belongs to the family of faces {113}.

[0113] As will be explained in the examples below, the present invention provides a solution based on the use of a mosaic of selected single crystal diamond seeds with specific structural properties and arranged in a specific manner. In particular, the seeds are selected and arranged according to the value of the angle that indicates the direction of propagation of the wavefront. This contributes to the formation of large single crystal diamond plates with high quality joints. [Example]

[0114] Formation of reference single crystal diamond plates 50 8mm x 8mm single crystal diamond seeds were selected and placed in a 32cm 2The single crystal diamond seed used had the following structural characteristics: - a growth surface comprising a terrace structure with crystal orientation planes of the family of planes {100} and {113}, - Terrace structure misorientation angle of approximately 3° (accuracy of approximately 1°).

[0115] For each single crystal diamond seed, an angular value is provided that indicates the direction of propagation of the wavefront.

[0116] The different single crystal diamond plates shown below are formed by plasma-assisted chemical vapor deposition as presented in C. Findeling-Dufour and al., Diamond and Related Materials 4 (1995) 428-434 or A. Tallaire and al. Growth of large size diamond single crystals by plasma assisted chemical vapor deposition: Recent achievements and remaining challenges / CRPhysics 14 (2013) 169-184.

[0117] Method for measuring the quality of the bond on a single crystal diamond seed: 1332.5cm -1 Measurements of the width at half height of the Raman peak of a single-crystal diamond plate located at are performed using a 473 nm laser with a 400 mW power output and a 100x objective lens at 298 K. Measurements are performed on the surface of the single-crystal diamond plate along a line including the single-crystal diamond seeds and their junctions, or as described in VG Ralchenko, et al., Thermal Conductivity of Diamond Mosaic Crystals Grown by Chemical Vapor Deposition: Thermal Resistance of Junctions; PHYS.REV.APPLIED 16, 014049 (2021).

[0118] The bond is defined by its quality, which reflects the presence or absence of crystal defects. Three types of bond are defined to allow assessment of the overall quality of the formed single crystal diamond plate: - Type 1 junctions are characterized by the presence of step and terrace wavefronts that may have different orientations from the adjacent species, but also by the presence of crystalline defects such as twins and dislocations. This type of junction has a width at half height of the Raman peak of 6 cm. -1 It is characterized by exceeding - Type 2 junctions are characterized by the presence of dislocations only. This type of junction has a width at half height of the Raman peak of 3 cm. -1 ~5.9cm -1 It is characterized in that: - Type 3 junctions are characterized by the absence of crystal defects, especially the absence of twins and dislocations. This type of junction has a width at half height of the Raman peak of 2.5 cm. -1 Over 2.9cm -1 It is characterized in that it is less than

[0119] Table 1 below shows the main characteristics of the various single crystal diamond seed configurations used to form the single crystal diamond plates and measurements of the quality of the bond produced relative to each reference single crystal diamond plate. - DIAM01: Adjacent single crystal diamond seeds are randomly arranged, and the angle values ​​indicating the propagation directions of different wavefronts are parts of a circle (0°~360°). - DIAM02: Adjacent single crystal diamond seeds are arranged in the same propagation direction of the wavefront, and the difference in the values ​​of the angles indicating the propagation directions of the wavefront of all single crystal diamond seeds is comprised within an interval of + or - 45°. - DIAM03: Adjacent single crystal diamond seeds are arranged in the same propagation direction of the wavefront, and the difference in the values ​​of the angles indicating the propagation direction of the wavefront of all single crystal diamond seeds is within an interval of + or - 15°. The single crystal diamond seeds are arranged in the order of decreasing thickness in the propagation direction of the wavefront of one of the seeds of the mosaic. - DIAM04: Adjacent single crystal diamond seeds are arranged in the same propagation direction of the wavefront FO, and the difference in the values ​​of the angles indicating the propagation direction of the wavefront FO of all single crystal diamond seeds is included within an interval of + or - 15°. The single crystal diamond seeds are arranged in the order of increasing thickness in the propagation direction of the wavefront of one of the seeds of the mosaic. - DIAM05: Adjacent single crystal diamond seeds are arranged in the same propagation direction of the wavefront, and the difference in the values ​​of the angles indicating the propagation direction of the wavefront of all single crystal diamond seeds is included in the interval [0°;5°].

[0120] [Table 1]

[0121] These results demonstrate that the placement of the single-crystal diamond seed during mosaic formation is particularly important. Indeed, these results show that the quality of the bond between the single-crystal diamond plates is significantly improved when the single-crystal diamond seed has a first value representing the angle indicating the wavefront propagation direction, and the difference between the first and second values ​​is 5° or less. As a result, Figure 10 shows a portion of the reference plate DIAM05, where the absence of crystal defects can be observed with the naked eye at the bond 10-1 between the plates.

[0122] Furthermore, these results show that arranging the single crystal diamond seeds according to increasing or decreasing thickness relative to the direction of propagation of the wavefront allows for an improvement in the quality of the bond formed.

[0123] The present invention may be subject to numerous variations and applications other than those described above. In particular, unless otherwise specified, the various structural and functional characteristics of each of the above implementations should not be considered as combined with each other and / or as closely and / or inseparably related to each other, but rather should be considered as simply arranged. Furthermore, the structural and / or functional characteristics of the various embodiments described above may be, in whole or in part, subject to any different arrangement or any different combination.

Claims

1. 1. A method (100) for producing a single crystal diamond plate from a plurality of single crystal diamond seeds (10, 11, 12, 13) comprising growth surfaces, the growth surfaces comprising terrace structures, the terrace structures having a plurality of crystal orientation planes (OC1, OC2), the crystal orientation planes (OC1, OC2) comprising a family of {100} planes or a family of {100} and {113} planes, the method comprising the steps of: Providing (110) said single crystal diamond seeds (10, 11, 12, 13), each of said seeds being associated with a structural characteristic, said structural characteristic being at least Wavefront (FO 10 , F.O. 11 ) propagation direction (D 10 , D 11 a first value representing an angle indicating the a misorientation angle (δ) of the terrace structure of 0° or more and 10° or less; and A step (130) of arranging the single crystal diamond seeds (10, 11, 12, 13) in a mosaic pattern, wherein two adjacent single crystal diamond seeds have a wavefront (FO 10 , F.O. 11 ) propagation direction (D 10 , D 11 ) the difference between the first and second values ​​being 5° or less, preferably 1° or less; a step (140) of lateral epitaxial growth of said terrace structure according to a crystal orientation (OC2) by enhanced chemical vapor deposition of a monocrystalline layer, preferably by plasma or hot filament; A manufacturing method (100) comprising:

2. 2. A method (100) according to claim 1, wherein the step (140) of lateral epitaxial growth according to the crystallographic orientation (OC2) is followed by a step (150) of second vertical epitaxial growth of the terraced structure according to a crystallographic orientation (OC1) of the family of planes {100}, to form a single-crystalline diamond epitaxial layer (10-2).

3. The method further comprises the step of calculating (120) a second value representing an angle indicating the direction of propagation of the principal wavefront (FO) of the plurality of single crystal diamond seeds (10, 11, 12, 13) from the first value representing the direction of propagation for each single crystal diamond seed (10, 11, 12, 13), wherein during the step of arranging the single crystal diamond seeds in a mosaic, each single crystal diamond seed (10, 11, 12, 13) has a wavefront (FO) angle ranging from -5° to +5°, preferably from -2.5° to +2.5° relative to the second value. 10 , F.O. 11 ) propagation direction (D 10 , D 11 3. The method of claim 1 or 2, comprising an angle representing

4. The method further comprises a step (115) of finishing the surface of the crystal orientation planes (OC1, OC2) of the single crystal diamond seeds (10, 11, 12, 13) by lithography or laser, wherein the seeds are oriented in substantially identical wavefronts (FO 10 , F.O. 11 ) propagation direction (D 10 , D 11 4. The method of claim 1, further comprising the step of: forming a groove having an angle indicative of a slit in the groove;

5. The method comprises a step (115') of laser or lithographically refinishing the surface of the single crystal diamond plate after removing (160) the single crystal diamond epitaxial layer (10-2), wherein said step (115') of refinishing the surface comprises: removing a predetermined thickness of said single crystal diamond plate; Formation of predetermined new terrace structures having crystal orientation planes (OC1, OC2) of single crystal diamond seeds (10, 11, 12, 13) including a family of {100} planes or crystal orientation planes (OC1, OC2) of single crystal diamond seeds (10, 11, 12, 13) including a family of {100} and {113} planes The manufacturing method (100) according to claim 2 or claim 3 or claim 4 depending on claim 2, comprising:

6. The seeds of the new terrace structure are formed during the step (115') of resurfacing by laser or lithography, resulting in a substantially identical wavefront (FO 10 , F.O. 11 ) propagation direction (D 10 , D 11 6. The method of claim 5, wherein the angle indicates a

7. 7. A method (100) according to any one of claims 1 to 6, wherein the step (140) of epitaxial lateral growth of the terraced structures following the crystallographic orientation (OC2) of the single crystal diamond seeds (10, 11, 12, 13) comprises the step (141) of introducing a suitable gas to prevent the generation of stress or the formation of crystal defects, preferably twins and dislocations, at the interface between the seeds.

8. The method (100) according to any one of the preceding claims, wherein the terrace structure comprises a macroscopic growth step.

9. The manufacturing method (100) of any one of claims 1 to 8, wherein the method further comprises the step of making the core (142) "XV-" by doping with an appropriate gas "X" followed by electron beam irradiation and annealing.

10. The single crystal diamond seed has a wavefront (FO 10 , F.O. 11 ) angle (D 10 , D 11 10. The method (100) according to any one of claims 1 to 9, wherein the layers are arranged in order of increasing thickness according to a propagation direction defined by one of the following:

11. A single crystal diamond plate (1) obtainable by the manufacturing method (100) according to any one of claims 1 to 10, wherein at least 15%, preferably at least 50%, more preferably at least 85% of the joints formed between the single crystal diamond seeds have a width at half height of the Raman peak of 2.5 cm -1 Over 2.9 cm -1 A single crystal diamond plate (1) having a thickness of less than 1000 nm.

12. A single crystal diamond obtainable by the manufacturing method (100) according to any one of claims 1 to 10, having a surface comprising at least a first crystal face and a second crystal face, wherein each of the crystal faces is associated with a concentration of a central "XV-", and the concentration of the central "XV-" of the first crystal face is greater than the concentration of the central "XV-" of the second crystal face.

13. 13. A single crystal diamond according to claim 12, wherein said first crystallographic face of said single crystal diamond belongs to the family of {113} planes.

14. 14. Use of a single crystal diamond plate according to claim 11 or a single crystal diamond according to claim 12 or 13 for the production of optical windows, substrates for semiconductors, substrates for thermal management, substrates for quantum technology, or gem diamonds, preferably diamonds larger than 5 carats, preferably larger than 15 carats.

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