Device for diffusing precursor including container having at least one porous element for generating aerosol to growth surface

Abstract

To provide a precursor diffusion device configured to diffuse a growth precursor towards an external growth surface included on an external growth member.SOLUTION: A diffusion device (1) includes a container (10) including at least one porous element (30) having a porosity configured to allow or prevent the passage of a precursor fluid (15) through a thickness (e31) of the porous element (30), the porous element (30) being configured so that the precursor fluid (15) which passes through the thickness (e31) of the porous element (30) generates an aerosol (17) by fragmentation of the precursor fluid (15), the aerosol (17) being formed of droplets of the precursor fluid (15). Also, there is provided a method for depositing a layer (103) on a growth surface (s101) by such a diffusion device (1).SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a precursor diffusion device configured to diffuse growth precursors towards an outgrowth surface configured on an outgrowth member.

[0002] The present invention also relates to a deposition method for growing a layer on a growth surface, the deposition method comprising the step of providing a diffusion device as described above, in which at least one receiving enclosure is at least partially filled with a precursor fluid. [Background technology]

[0003] The increasing share of renewable energies in the global energy mix will increase the intermittency of electrical energy supplies. To compensate for this intermittency, it will be necessary to combine intermittent energy sources with stable and flexible third-party energy sources. If this third-party energy source is nuclear power, this compensation will increase the number of power transients (shortage periods), which occur more frequently at nuclear power plants.

[0004] This increase in power transients directly affects certain components, such as the fuel pellets and the cladding they are housed in. It is necessary to find a solution to suppress this problem, known as PCI (pellet-cladding interaction).

[0005] During an event or accident resulting in a power increase (total or partial), the PCI expands more strongly compared to the cladding, corresponding to the tension on the fuel rod cladding due to the interaction with the fuel pellets. When the interaction between the pellets and the cladding is essentially mechanical, this is called PCmI. PCmI occurs after a power pulse, i.e., when the power level is not maintained after a sudden increase in power. Therefore, in such situations and at medium or high burnups, the deformation of the fuel cladding should be limited to prevent cladding failure, which could lead to fuel diffusion in the main circuit, especially in the presence of insertion reaction transients.

[0006] Accidents characterized by sustained power after a power surge pose a risk of cladding failure known as PCI I-SCC, an iodine-induced stress corrosion cracking that can cause rupture without threatening fuel proliferation. Summary of the Invention [Problem to be solved by the invention]

[0007] It is known in the art to propose cladding tubes with internal layers that can reduce or eliminate the effects of PCI, but most mature methods for creating such internal layers result in large thickness non-uniformities over lengths measured in centimeters or meters.

[0008] The object of the present invention is to propose a solution that addresses all or some of the above mentioned problems. [Means for solving the problem]

[0009] This object can be achieved by implementing a precursor diffusion device configured to diffuse growth precursors towards an external growth surface included in an external growth member, said diffusion device comprising a container defining at least one receiving enclosure therein, said container being at least partially constituted by at least one porous element, said porous element defining an internal inner surface, said internal surface at least partially defining the at least one receiving enclosure, said porous element defining an external diffusion surface facing towards the external growth surface.

[0010] The at least one receiving enclosure is configured to contain a precursor fluid including the growth precursor.

[0011] The diffusion device includes a precursor fluid contained in the receiving enclosure.

[0012] The porous element has a porosity configured, on the one hand, to allow the precursor fluid to pass through the thickness of the porous element measured between the inner surface and the diffusion surface (pass through the porous element in the thickness direction) as long as the pressure of the precursor fluid contained in the receiving enclosure is strictly higher than a threshold pressure, and, on the other hand, to prevent the precursor fluid from passing through the thickness of the porous element when the pressure of the precursor fluid contained in the receiving enclosure is lower than the threshold pressure, which is strictly higher than the external pressure prevailing outside the container.

[0013] The porous element is configured such that the precursor fluid passing through the thickness of said porous element generates an aerosol from the diffusion surface by atomization of the precursor fluid.

[0014] The aerosol is formed from droplets of a precursor fluid and is contained between a diffusion surface and an external growth surface.

[0015] The above-described configuration provides a diffuser device configured to generate an aerosol containing droplets of a precursor fluid at the growth surface. Advantageously, the diffuser device allows for control of both the type of precursor fluid contained in the diffused aerosol and the amount of the diffused aerosol. Furthermore, the aerosol can be locally diffused near the growth surface, thus limiting precursor fluid losses. The diffuser device also allows for the precursor fluid to be uniformly dispersed over the entire growth surface, avoiding inhomogeneities, even in a highly dispersed or gaseous liquid form. The fragmentation of the precursor fluid can improve its volatility and reactivity, especially when used for chemical vapor deposition in a chemical growth reactor.

[0016] The diffusion device may have one or more of the following features, either alone or in combination:

[0017] According to one embodiment, the porous element comprises a metallic material, for example the porous element is made of a metallic material.

[0018] According to one embodiment, the metallic material of the porous element is steel.

[0019] According to one embodiment, the metallic material of the porous element is based on nickel, aluminum or tungsten.

[0020] According to one embodiment, the porous element is configured to withstand the pressures and temperatures used in chemical vapor deposition processes, for example, the porous element is configured to survive temperatures comprised between 1000°C and 1500°C.

[0021] Thus, the diffusion device is suitable for use in chemical vapor deposition processes.

[0022] According to one embodiment, the diffuser is configured to deliver an aerosol comprising at least one precursor agent to the growth surface in a manner that allows for the growth of a layer on the growth surface. For example, the layer may be a protective layer. Advantageously, the diffuser allows for the thickness of the protective layer grown on the growth surface to be controlled.

[0023] According to one embodiment, the precursor fluid is a liquid, for example the precursor fluid may comprise a solid precursor agent dissolved in a solvent, or the precursor fluid may comprise a mixture of a solvent and a liquid precursor agent.

[0024] According to one embodiment, the precursor agent comprises chromium oxide (Cr2O3).

[0025] According to one embodiment, the container is formed entirely of a porous element.

[0026] According to one embodiment, the porous element is a porous filtering material obtained by a process carried out according to one of the embodiments described in patent application FR 3118429 (FR 2014263), the contents of which are incorporated herein by reference to the extent permitted by law.

[0027] According to one embodiment, the porous element has pores with an average diameter between 2 μm and 100 μm.

[0028] According to one embodiment, the threshold pressure is 2·10 5 Pa and 20·10 5 Between Pa.

[0029] According to one embodiment, the diffusion device comprises at least one pressurizing member configured to change the pressure of the precursor fluid in the receiving enclosure so as to set the precursor fluid at a pressure higher than a threshold pressure, allowing the precursor fluid to pass through the porous element from the inner surface towards the diffusion surface.

[0030] According to one embodiment, the pressure member comprises a pneumatic pump.

[0031] According to one embodiment, the container extends generally along a longitudinal axis and has a sealed end and a fluid inlet end spaced apart from one another along the longitudinal axis, the porous element is disposed between the two ends, and the receiving enclosure is configured to receive the precursor fluid at the fluid inlet end and to be closed at the sealed end.

[0032] According to one embodiment, at least one pressure member is disposed at the fluid inlet end of the porous element.

[0033] According to one embodiment, the diffusing surface of the porous element has a first prismatic shape characterized by a first basic contour, the first prismatic shape being formed by linearly translating the first basic contour along the longitudinal axis, and the inner surface of the porous element has a second prismatic shape characterized by a second basic contour, the second prismatic shape being formed by linearly translating the second basic contour along the longitudinal axis.

[0034] According to one embodiment, at least one surface selected from the diffusing surface and the internal surface of the porous element is in the full or partial shape of a cylindrical surface.

[0035] A "cylindrical surface" is to be understood mathematically as a three-dimensional surface generated by a generatrix moving in a given direction based on a closed curve called the directrix. In this example, the directrix corresponds to the cross-sectional outline of the container in the porous element, and the generatrix is ​​oriented parallel to the longitudinal axis.

[0036] According to one embodiment, the diffusing surface is tubular.

[0037] According to one embodiment, the inner surface is tubular.

[0038] According to one embodiment, the cross section of the container is circular.

[0039] According to one embodiment, the first basic contour is a circle of a first radius and the second basic contour is a circle of a second radius that is strictly smaller than the first radius, and the thickness of the porous element is equal to the difference between the first and second radii.

[0040] According to one embodiment, the porous element has a length, measured longitudinally along its longitudinal axis, said length being precisely greater than 80 cm, in particular precisely greater than 2 m.

[0041] According to one embodiment, the diffusion device comprises: a first receiving enclosure defined by a first inner surface and configured to receive a first precursor fluid; a second receiving enclosure defined by a second inner surface and configured to receive a second precursor fluid; It has.

[0042] It is clear that the use of the terms "first" and "second" is not limiting and that according to this embodiment there may be at least one additional receiving enclosure having the same properties and to which the same principles apply as the first and second receiving enclosures. In other words, the container may define at least three separate receiving enclosures, each capable of containing the same or different precursor fluids from one enclosure to the other.

[0043] According to one embodiment, the first precursor fluid is different from the second precursor fluid.

[0044] In this way, two different types of aerosols can be generated through a single diffuser, for example, which allows for localized diffusion of two different precursor types at the growth surface.

[0045] According to one embodiment, the first precursor fluid and the second precursor fluid are the same.

[0046] According to one embodiment, the first thickness measured between the first inner surface of the porous element and the diffusing surface is strictly greater than the second thickness measured between the second inner surface of the porous element and the diffusing surface.

[0047] In this way, the thickness through which the precursor fluid passes can be adapted depending on the receiving enclosure containing the precursor fluid and / or the properties of this precursor fluid, and therefore the diameter of the aerosol produced or of the droplets that compose it can vary.

[0048] According to one embodiment, the diffusion device comprises a pressure member associated with each receiving enclosure, so that the pressure set by the first precursor fluid and the pressure set by the second precursor fluid can be adapted depending on the properties of the precursor fluids used.

[0049] According to one embodiment, the second precursor fluid comprises a coolant configured to cool the porous element.

[0050] According to one embodiment, the diffusion device comprises an assembly member arranged at an assembly end of the diffusion device, the assembly member being configured to allow an external element selected from another diffusion device and a growth member to be fixed to the assembly end.

[0051] The above configuration allows multiple diffusers to be combined together to match the shape of the growth surface.

[0052] According to one embodiment, the assembly end is located at the fluid inlet end of the container as viewed along the longitudinal axis.

[0053] According to one embodiment, the porous element is obtained by three-dimensional fabrication (commonly called 3D printing).

[0054] Advantageously, manufacturing the porous element by three-dimensional fabrication allows both to easily define the shape of the porous element, even if this shape is complex, and to reduce manufacturing costs.

[0055] Furthermore, it is possible to obtain particular geometries of the porous element, for example geometries that integrate several receiving enclosures in which different precursor fluids can be stored before the pressurization step is carried out.

[0056] Furthermore, 3D printing can easily provide at least one assembly member at the assembly end of the diffusion device.

[0057] According to one embodiment, the porous element is obtained by powder fusion.

[0058] According to one embodiment, the container is configured to be insertable into the tubular cladding.

[0059] According to one embodiment, the growth member has a tubular cladding.

[0060] According to one embodiment, the growth member has at least one flange adapted to mate with the diffuser, for example at the assembly end of the diffuser.

[0061] The object of the present invention can also be achieved by implementing a film formation method for growing a layer on a growth surface, the film formation method comprising: a preparation step in which the aforementioned diffusion device is provided, wherein at least a portion of at least one receiving enclosure is filled with a precursor fluid; providing a growth member having a growth surface; a positioning step in which the growth surface is positioned opposite a diffusion surface of a diffusion device; pressurizing the receiving enclosure of the diffusion device by setting the precursor fluid at a pressure higher than a threshold value so that the precursor fluid can pass through the thickness of the porous element to generate an aerosol by atomization of the precursor fluid as it passes through the thickness of the porous element and direct the aerosol formed of droplets of the precursor fluid towards the growth surface; a growing step in which the aerosol undergoes a chemical reaction at the growing surface to form the layer; Includes.

[0062] The above-described configuration allows for a film formation method in which an aerosol containing droplets of a precursor fluid is sprayed locally onto the growth surface. In this way, both the type and amount of the aerosol dispersed can be controlled, thereby minimizing loss of the precursor fluid.

[0063] The deposition method may also have one or more of the following features, either alone or in combination.

[0064] According to one embodiment, the positioning step is performed before the pressing step.

[0065] In this way, the outer surface of the porous element can be placed opposite the growth surface to ensure that local aerosol generation close to the growth surface is uniform across the growth surface.

[0066] According to one embodiment, the diffusion device is provided with at least one pressure member configured to perform the pressure step.

[0067] According to one embodiment, the at least one pressurizing member is configured to inject pressurized gas into the receiving enclosure.

[0068] According to one embodiment, at least one step selected from the placing step, the pressurizing step, and the growing step is carried out in a growth chamber of a chemical growth furnace, preferably in a growth chamber of a chemical vapor deposition furnace.

[0069] In this way, the pressurization step allows the precursor agents contained in the precursor fluid to be supplied locally at the growth surface in order to enable the growth of a layer in the chemical vapor deposition furnace during the growth step.

[0070] According to one embodiment, the growth step is carried out in a chemical growth furnace such that the chemical growth furnace brings the growth chamber to a growth temperature and heats the growth member and the diffusion device at said growth temperature to promote chemical reaction of the aerosol at the growth surface.

[0071] According to one embodiment, the growth temperature is comprised between 1000 and 1500°C.

[0072] According to one embodiment, during the growth step, the chemical growth furnace sets the growth chamber to a growth pressure to create a growth vacuum that allows for the growth of a layer on the growth surface.

[0073] According to one embodiment, the growth pressure is 10 -6 Lower than Pa.

[0074] According to one embodiment, the growth chamber is placed in an inert atmosphere during the growth step, said inert atmosphere being obtained by injection of an inert gas, for example argon or nitrogen.

[0075] According to one embodiment, the pressurizing gas used during the pressurizing step is the same as the inert gas used to place the growth chamber in an inert atmosphere.

[0076] According to an embodiment in which the porous element comprises a first receiving enclosure and a second receiving enclosure, the second receiving enclosure can be configured to receive a coolant configured to cool the porous element during the growth step, so that the porous element can be cooled to avoid undesired growth of the precursor fluid in the pores of the porous element, which may lead to clogging of said pores of the porous element and / or disruption of uniform growth on the growth surface.

[0077] According to one embodiment, the step of preparing the diffusion device comprises manufacturing the porous element by three-dimensional fabrication.

[0078] Advantageously, manufacturing the porous element by 3D printing allows for easy shaping of the porous element, even complex shapes, and reduces manufacturing costs.

[0079] Furthermore, the porous element may have a particular shape, for example one that integrates several receiving enclosures in which different precursor fluids can be stored before the pressurization step is carried out.

[0080] Furthermore, 3D printing can easily provide at least one assembly member at the assembly end of the diffusion device.

[0081] According to one embodiment, the porous element is obtained by powder fusion.

[0082] According to one embodiment, the deposition method includes a filling step of introducing a precursor fluid into at least one receiving enclosure of the diffusion device.

[0083] According to one embodiment, the filling step is carried out before the pressurizing step.

[0084] According to one embodiment, the providing step includes providing a diffusion device, the first basic outer shape being a circle with a first radius and the second basic outer shape being a circle with a second radius strictly smaller than the first radius, the thickness of the porous element being equal to the difference between the first and second radii. The providing step includes providing a generally tubular growth member along a major axis, the growth member defining an outwardly opening cavity therein with an insertion opening located at one end of the growth member considered to be along the major axis, the cavity being formed into a third prismatic shape defining at least the growth surface and characterized by a third basic outer shape, the third prismatic shape being formed by linear translation of the third basic outer shape along the major axis, the third basic outer shape being a circle with a radius strictly larger than the first radius. The disposing step includes inserting a diffusion device into the cavity of the growth member through the insertion opening along the major axis.

[0085] According to one embodiment, the main axis is parallel to or coincident with the longitudinal axis.

[0086] According to one embodiment, the length of the porous element measured along the longitudinal axis of the container is strictly greater than the length of the growth member measured along the main axis, and after the step of inserting the diffusion device inside the growth member, the entire growth surface faces at least a portion of the outer surface of the porous element.

[0087] In this way, the aerosol is generated uniformly along the entire length of the growth member and uniformly across the entire growth surface.

[0088] Finally, the object of the invention can be achieved by implementing a system comprising a diffusion device of one of the types described above and a growth member.

[0089] Other aspects, objects, advantages and features of the present invention will become more apparent from the following detailed description of preferred embodiments given by way of non-limiting example and illustrated with reference to the accompanying drawings. [Brief explanation of the drawings]

[0090] [Figure 1] FIG. 1 is a schematic cross-sectional view of a precursor diffusion device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view of a precursor diffusion device according to a second embodiment of the present invention. [Figure 3] FIG. 3 is a schematic perspective view of two precursor diffusion devices according to one embodiment of the present invention. [Figure 4] FIG. 4 is a schematic cross-sectional view of the precursor diffusion device and growth member according to the embodiment of FIG. [Figure 5] FIG. 5 is a schematic diagram illustrating some steps of a deposition method according to a particular embodiment of the present invention. [Figure 6] FIG. 6 is a schematic diagram illustrating some steps of a deposition method according to a particular embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0091] In the figures and in the following description, the same reference numerals represent the same or similar elements. Also, for clarity of the figures, different elements are not drawn to scale. Furthermore, different embodiments and variants are not mutually exclusive and can be combined together.

[0092] As shown in Figures 1 to 6, the present invention relates to a precursor diffusion device 1 configured to diffuse growth precursors towards a growth surface s101. The growth surface is included in an external growth element 100, for example having a tubular cladding 101. Such a growth element 100 can advantageously be used to house fuel pellets. The present invention also relates to a deposition method for depositing a layer 103 on the growth surface s101. Advantageously, this deposition method can therefore be used to deposit a protective layer 103 on the cladding housing the fuel pellets in order to limit or eliminate the effects of PCI.

[0093] As will be explained in more detail below regarding this deposition method, the diffusion device 1 is suitable for use in chemical vapor deposition. Therefore, the diffusion device 1 is suitable for use at temperatures between 1000°C and 1500°C, and / or generally above 1000°C. -6 It is configured to maintain its original shape at low pressures of less than 100 Pa.

[0094] 1 and 2, the diffusion device 1 comprises a container 10 defining at least one receiving enclosure 11 therein. The container 10 is at least partially comprised of at least one porous element 30 defining an interior surface s31 therein and a diffusion surface s33 therein facing the external growth surface s101. The interior surface s31 then at least partially defines the at least one receiving enclosure 11.

[0095] Advantageously, the porous element 30 consists essentially of or includes a metallic material, which includes at least one of aluminum, stainless steel, nickel, or tungsten in elemental, alloy, or oxide form.

[0096] 1 and 2, the container 10 extends generally along a longitudinal axis X and has a sealing end 19 and a fluid inlet end 21 spaced apart from one another along the longitudinal axis X. A porous element 30 is located between these ends, and the receiving enclosure 11 can be closed at the sealing end 19. According to these variations, the container 10 is entirely formed by the porous element 30. The porous element 30 has, for example, a length L1 measured longitudinally along the longitudinal axis X that is precisely greater than 80 cm, and in particular, precisely greater than 2 m. Furthermore, the diffusing surface s33 of the porous element 30 can have a first prismatic shape (a rectangular column shape) characterized by a first basic contour, which is created by linearly translating the first basic contour along the longitudinal axis X. The inner surface s31 of the porous element 30 has a second prismatic shape characterized by a second basic contour, which is created by linearly translating the second basic contour along the longitudinal axis X. More specifically, at least one surface selected from the diffusing surface s33 and the inner surface s31 of the porous element 30 has the shape of a whole or part of a cylindrical surface. FIG. 1 particularly illustrates a variant in which the diffusing surface s33 and the inner surface s31 have the shape of a cylindrical surface. Mathematically, a "cylindrical surface" refers to a three-dimensional curved surface generated by a generatrix that moves in a predetermined direction based on a closed curve called a directrix. In this example, the directrix corresponds to the outer shape of the cross section of the container 10 in the porous element 30, and the generatrix is ​​oriented parallel to the longitudinal axis X. According to this embodiment, the cross section of the container 10 is circular so that the container 10 can be inserted into the tubular cladding 101. Therefore, according to the variant illustrated in FIG. 1, it is clear that the diffusing surface s33 and the inner surface s31 are tubular. In other words, the first basic outer shape is a circle having a first radius r1, and the second basic outer shape is a circle having a second radius r2 that is strictly smaller than the first radius r1.

[0097] The at least one receiving enclosure 11 of the diffusion device 1 is configured to contain a precursor fluid 15 containing a growth precursor. Generally, the receiving enclosure 11 is configured to receive the precursor fluid 15 at the fluid inlet end 21. Thus, the diffusion device 1 includes the precursor fluid 15 contained in the receiving enclosure 11. According to a first embodiment, the precursor fluid 15 is liquid. For example, the precursor fluid 15 may include a solid precursor agent dissolved in a solvent. Alternatively, the precursor fluid 15 may include a mixture of a solvent and a liquid precursor agent. According to one embodiment, the precursor agent includes chromium oxide Cr2O3. In a non-limiting variation shown in FIG. 2, the diffusion device 1 includes a first receiving enclosure 11a defined by a first inner surface s31a and configured to receive the first precursor fluid 15a, and a second receiving enclosure 11b defined by a second inner surface s31b and configured to receive the second precursor fluid 15b. The use of the terms "first" and "second" is not limiting, and it is clear that this embodiment allows for at least one additional receiving enclosure 11 of the same nature and to which the same principles apply as the first and second receiving enclosures 11a, 11b. In other words, the container 10 may separate at least three separate receiving enclosures 11, each containing the same or different precursor fluids 15 from one enclosure to the other. Thus, the first precursor fluid 15a may be different from the second precursor fluid 15b. In this way, two different types of aerosols can be generated using a single diffusion device 1. This allows, for example, two different types of precursors to be locally diffused alternately or simultaneously at the growth surface s101. For example, the second precursor fluid 15b may contain a coolant configured to cool the porous element 30. Alternatively, the first precursor fluid 15a and the second precursor fluid 15b may be identical.

[0098] The porous element 30 has a porosity configured to allow the precursor fluid 15 to pass through the thickness e31 of the porous element 30, measured between the inner surface s31 and the diffusion surface s33, as long as the pressure of the precursor fluid 15 contained in the receiving enclosure 11 is strictly higher than a threshold pressure, and to prevent the precursor fluid 15 from passing through the thickness e31 of the porous element 30 when the pressure of the precursor fluid 15 contained in the receiving enclosure 11 is lower than the threshold pressure. For example, the porous element 30 may have pores with an average diameter between 2 μm and 100 μm. The threshold pressure is strictly higher than the external pressure prevailing outside the container 10. For example, the threshold pressure is between 2·105 Pa and 20·105 Pa. The porous element 30 is further configured so that the precursor fluid 15 that has penetrated the thickness e31 of the porous element 30 generates an aerosol 17 by fragmentation of the precursor fluid 15 from the diffusion surface s33. The aerosol 17 takes the form of droplets of precursor fluid 15 and is contained between the diffusion surface s33 and the external growth surface s101. According to the variant shown in FIG. 1, the thickness e31 of the porous element 30 is equal to the difference between the first radius r1 and the second radius r2. According to the variant shown in FIG. 2, a first thickness e31a is measured between the first inner surface s31a of the porous element 30 and the diffusion surface s33, and a second thickness e31b is measured between the second inner surface s31b of the porous element 30 and the diffusion surface s33. The first thickness e31a is strictly greater than the second thickness e31b. In this way, the thickness e31 through which the precursor fluid 15 passes can be adapted depending on the receiving enclosures 11a, 11b containing it and / or the nature of this precursor fluid 15. The diameter of the generated aerosol 17 or the droplets that compose it may therefore vary.

[0099] In general, the diffusion device 1 is configured to deliver an aerosol 17 comprising at least one precursor agent to the growth surface s101 so as to enable the growth of a layer 103 on the growth surface s101. For example, the layer 103 may be a protective layer 103. Advantageously, the diffusion device 1 allows for control of the thickness of the protective layer 103 deposited on the growth surface s101.

[0100] FIG. 3 illustrates the formation of the aerosol 17 by two different diffusion devices 1. As shown in FIG. 3, the diffusion device 1 may have at least one pressurizing member 50 configured to change the pressure of the precursor fluid 15 in the receiving enclosure 11 so as to set the precursor fluid 15 at a pressure higher than a threshold pressure, allowing the precursor fluid 15 to pass through the porous element 30 from the inner surface s31 toward the diffusion surface s33. For example, the pressurizing member 50 may comprise an air pressure pump. The at least one pressurizing member 50 may be disposed at the fluid inlet end 21 of the porous element 30. In a non-limiting example in which the diffusion device 1 has two receiving enclosures 11a, 11b, the diffusion device 1 may have a pressurizing member 50 associated with each receiving enclosure 11a, 11b. Thus, the pressure at which the first precursor fluid 15a and the second precursor fluid 15b are set can be adapted depending on the properties of the precursor fluids 15a, 15b used.

[0101] Finally, with particular reference to FIG. 4 , the diffuser 1 may have an assembly element 53 arranged at the assembly end 55 of the diffuser 1. For example, the assembly end 55 may be arranged at the fluid inlet end 21 of the vessel 10, as viewed along the longitudinal axis X. The assembly element 53 is configured to fasten an external element selected from another diffuser and a growth element 100 at the assembly end 55. This configuration allows several diffusers to be assembled together to match the shapes of the growth surfaces s101. However, as shown in FIG. 4 , the assembly element 53 is configured to fasten a growth element 100. According to this variant, the diffuser has two assembly elements 53 integrally formed with the porous element. These assembly elements 53 have an annular shoulder disposed about the longitudinal axis X. In this case, the growth element 100 may have at least one flange 105 configured to cooperate with the diffuser 1, for example, at the assembly end 55 of the diffuser 1. FIG. 4 therefore represents a non-limiting variant in which two flanges 105 cooperate with the assembly member 53 of the diffusion device 1 .

[0102] Advantageously, the porous element 30 can be obtained by three-dimensional shaping. Indeed, the production of the porous element 30 by three-dimensional shaping allows both a simple definition of the shape of the porous element 30, even if the shape is complex, and a reduction in production costs. Furthermore, the porous element 30 can also be shaped in a specific way, for example to integrate several receiving enclosures 11 a, 11 b capable of storing different precursor fluids 15 a, 15 b before the pressurization step is carried out. Furthermore, three-dimensional shaping allows a simple provision of at least one assembly element 53 at the assembly end 55 of the diffusion device 1.

[0103] Alternatively, the porous element 30 may be obtained by a powder fusion process.

[0104] The above-described configuration provides a diffuser 1 configured to generate an aerosol 17 comprising droplets of a precursor fluid 15 at the growth surface s101. Advantageously, the above-described diffuser 1 allows for control of both the type of precursor fluid 15 contained in the diffused aerosol 17 and the amount of the diffused aerosol 17. Furthermore, the aerosol 17 can be locally diffused near the growth surface s101. Any loss of the precursor fluid 15 is therefore minimized. Finally, the diffuser 1 allows for the precursor fluid 15, in highly atomized or gaseous liquid form, to be uniformly diffused over the entire growth surface s101, avoiding inhomogeneities. The atomization of the precursor fluid 15 can improve its volatility and reactivity, especially when used in chemical vapor deposition in a chemical growth reactor.

[0105] As mentioned above, the present invention also relates to a deposition method for depositing 103 on the growth surface s101 of the growth member 100.

[0106] For example, the deposition method shown in FIGS. 5 and 6 begins with a preparation step E10 in which a diffusion device 1, as described above, is prepared. The preparation step E10 of the diffusion device 1 may include a step E01 of manufacturing the porous element 30 by three-dimensional printing. Alternatively, the porous element 30 may be obtained by a powder fusion process. Advantageously, manufacturing the porous element 30 by 3D printing allows both easy definition of the shape of the porous element 30, even if it has a complex shape, and reduced manufacturing costs. Furthermore, 3D printing can provide at least one assembly member 53 at the assembly end 55 of the diffusion device 1, thereby facilitating the placement step E30, described below. Finally, the porous element 30 can be 3D printed to have a specific shape, for example, a shape that integrates multiple receiving enclosures 11a, 11b to store different precursor fluids 15a, 15b before performing the pressurization step E50, described below.

[0107] The deposition method then comprises a filling step E03 in which a precursor fluid 15 is introduced into at least one receiving enclosure 11 of the diffusion device 1. This filling step E03 is carried out before the pressurizing step E50. In this way, at least a portion of the at least one receiving enclosure 11 is filled with precursor fluid 15 during the preparation step E10.

[0108] The deposition method also includes a step E20 of providing a growth element 100 having a growth surface s101. According to a non-limiting variant illustrated in Figure 5, the growth element 100 is generally tubular along a major axis X2 and defines therein a cavity 107 that opens outward at an insertion opening 109 located at one end of the growth element 100 considered along the major axis X2. This cavity 107 defines, at least in part, said growth surface s101.

[0109] The deposition method further includes a disposing step E30 of disposing the growth surface s101 opposite the diffusion surface s33 of the diffusion device 1. As shown in FIG. 5, the preparing step E10 may include preparing a diffusion device 1 in which the thickness e31 of the porous element 30 is equal to the difference between the first radius r1 and the second radius r2, the first basic contour being a circle with a first radius r1 and the second basic contour being a circle with a second radius r2 that is strictly smaller than the first radius r1. The providing step E20 of the growth member 100 includes providing the growth member 100 in which the growth surface s101 is in the form of a third prismatic shape characterized by a third basic contour, the third prismatic shape being created by linearly moving the third basic contour along the major axis X2, the third basic contour being a circle with a radius r3 that is strictly larger than the first radius r1. Thus, the positioning step E30 may include a step E31 of inserting the diffusion device 1 into the cavity 107 of the growth member 100 through the insertion opening 109 along the main axis X2, which is parallel to or coincides with the longitudinal axis X. Advantageously, the length L1 of the porous element 30 measured along the longitudinal axis X of the container 10 is strictly greater than the length L2 of the growth member 100 determined along the main axis X2, so that after the step E31 of inserting the diffusion device 1 into the growth member 100, the entire growth surface s101 faces at least a portion of the outer surface of the porous element 30. In this way, the generation of aerosol 17 is uniform over the entire length L1 of the growth member 100 and the entire growth surface s101.

[0110] The deposition method further includes a step E50 of pressurizing the receiving enclosure 11 of the diffusion device 1, which is typically performed after the positioning step E30. In this way, the outer surface of the porous element 30 is positioned opposite the growth surface s101, ensuring that the local generation of aerosol 17 near the growth surface s101 is uniform throughout the growth surface s101. During this pressurizing step E50, the precursor fluid 15 is placed at a pressure higher than a threshold pressure so that it can pass through the thickness e31 of the porous element 30 to generate aerosol 17 by fragmentation of the precursor fluid 15 as it passes through the thickness e31 of the porous element 30, and the aerosol 17 is formed from droplets of the precursor fluid 15 and directed toward the growth surface s101. According to the embodiment shown in FIG. 6, the diffusion device 1 is provided with at least one pressurizing member 50 configured to perform the pressurizing step E50. For example, the pressurizing member 50 is configured to inject pressurized gas into the receiving enclosure 11.

[0111] Finally, this deposition method includes a growth step E60 in which the aerosol 17 undergoes a chemical reaction on the growth surface s101 to form the layer 103. Therefore, the growth step E60 can be performed in a chemical growth furnace, which sets the growth chamber to a growth temperature and heats the growth member 100 and the diffusion device 1 to the growth temperature to promote the chemical reaction of the aerosol 17 on the growth surface s101. For example, the growth temperature is between 1000°C and 1500°C. Furthermore, during this growth step E60, the chemical growth furnace can set the growth chamber to a growth pressure to generate a growth vacuum that enables the growth of the layer 103 on the growth surface s101. For example, the growth pressure is lower than 10 Pa. Finally, during the growth step E60, the growth chamber can be placed in an inert atmosphere, which can be achieved by injecting an inert gas, such as argon or nitrogen. Advantageously, the pressurizing gas used in the pressurizing step E50 is the same as the inert gas used to place the growth chamber in an inert atmosphere.

[0112] Typically, at least one step selected from the placing step E30, the pressurizing step E50 and the growing step E60 is carried out in a growth chamber of a chemical growth furnace, preferably a chemical vapor deposition furnace. Thus, the pressurizing step E50 allows the precursor agents contained in the precursor fluid 15 to be supplied locally at the growth surface s101, so that the layer 103 is grown in the chemical vapor deposition furnace during the growing step E60.

[0113] If the porous element 30 has a first receiving enclosure 11 a and a second receiving enclosure 11 b, the second receiving enclosure 11 b can be configured to receive a coolant configured to cool the porous element 30 during the growth step E60. Thus, the porous element 30 can be cooled to avoid unwanted growth of the precursor fluid 15 in the pores of the porous element 30, which could lead to clogging of said pores of the porous element 30 and / or disruption of the homogeneous growth on the growth surface s101.

[0114] The above-described configuration makes it possible to propose a deposition method in which an aerosol 17 comprising droplets of precursor fluid 15 is injected locally at the growth surface s101. In this way, both the type of aerosol 17 dispersed and the amount of aerosol 17 dispersed can be controlled. Any losses of precursor fluid 15 are therefore limited.

Claims

1. A precursor diffusion device (1) configured to diffuse a growth precursor towards an external growth surface (s101) comprised in an external growth element (100), said diffusion device (1) comprising a container (10) defining at least one receiving enclosure (11) therein, said container (10) being at least partially constituted by at least one porous element (30), said porous element (30) defining an internal surface (s31) therein, said internal surface (s31) defining at least partially said at least one receiving enclosure (11), said porous element (30) defining a diffusion surface (s33) facing towards said external growth surface (s101), said at least one receiving enclosure (11) being configured to contain a precursor fluid (15) comprising said growth precursor, The diffusion device (1) comprises the precursor fluid (15) contained in the receiving enclosure (11); the porous element (30) has a porosity configured, on the one hand, to allow the precursor fluid (15) to pass through a thickness (e31) of the porous element (30), measured between the inner surface (s31) and the diffusion surface (s33), as long as the pressure of the precursor fluid (15) contained in the receiving enclosure (11) is strictly higher than a threshold pressure, and, on the other hand, to prevent the precursor fluid (15) from passing through said thickness (e31) of the porous element (30) when the pressure of the precursor fluid (15) contained in the receiving enclosure (11) is lower than said threshold pressure, said threshold pressure being strictly higher than the external pressure prevailing outside the container (10), The porous element (30) is configured such that the precursor fluid (15) passing through the thickness (e31) of the porous element (30) generates an aerosol (17) by atomization of the precursor fluid (15) from the diffusion surface (s33), A diffusion device (1) in which the aerosol (17) is formed of droplets of the precursor fluid (15) and is contained between the diffusion surface (s33) and the external growth surface (s101).

2. Diffusion device (1) according to claim 1, The container (10) is a diffusion device (1) formed entirely of the porous element (30).

3. Diffusion device (1) according to claim 1, A diffusion device (1) comprising at least one pressurizing member (50) configured to change the pressure of the precursor fluid (15) in the receiving enclosure (11) so as to set the precursor fluid (15) at a pressure higher than a threshold pressure, and the precursor fluid (15) is able to pass through the porous element (30) from the inner surface (s31) towards the diffusion surface (s33).

4. Diffusion device (1) according to claim 1, The container (10) extends generally along a longitudinal axis (X) and has a sealing end (19) and a fluid inlet end (21) spaced apart from one another along the longitudinal axis (X), a porous element (30) is disposed between the two ends, and the receiving enclosure (11) is configured to receive a precursor fluid (15) at the fluid inlet end (21) and to be closed at the sealing end (19).

5. Diffusion device (1) according to claim 4, The diffusion surface (s33) of the porous element (30) has a first prism shape characterized by a first basic contour, and the first prism shape is formed by linearly translating the first basic contour along the longitudinal axis (X), and the inner surface (s31) of the porous element (30) has a second prism shape characterized by a second basic contour, and the second prism shape is generated by linearly translating the second basic contour along the longitudinal axis (X).

6. Diffusion device (1) according to claim 5, A diffusion device (1) in which the first basic outer shape is a circle with a first radius (r1) and the second basic outer shape is a circle with a second radius (r2) that is strictly smaller than the first radius (r1), and the thickness (e31) of the porous element (30) is equal to the difference between the first radius (r1) and the second radius (r2).

7. Diffusion device (1) according to claim 4, The porous element (30) has a length (L1) measured longitudinally along the longitudinal axis (X), said length (L1) being precisely greater than 80 cm, in particular precisely greater than 2 m.

8. Diffusion device (1) according to claim 1, a first receiving enclosure (11a) defined by a first inner surface (s31a) and configured to receive a first precursor fluid (15a); a second receiving enclosure (11b) defined by a second inner surface (s31b) and configured to receive a second precursor fluid (15b); A diffusion device (1) having:

9. Diffusion device (1) according to claim 1, The diffusion device (1) comprises an assembly member (53) disposed at an assembly end (55) of the diffusion device (1), the assembly member (53) being configured so that an external element selected from another diffusion device and a growth member (100) can be fixed to the assembly end (55).

10. Diffusion device (1) according to claim 1, A diffusion device (1) in which the porous element (30) is obtained by three-dimensional shaping.

11. Diffusion device (1) according to claim 1, A diffusion device (1) in which a container (10) is formed so as to be insertable into a tubular cladding (101).

12. A method for growing a layer (103) on a growth surface (s101), comprising: a preparation step (E10) in which a diffusion device (1) according to any one of claims 1 to 11 is prepared, in which at least one receiving enclosure (11) is at least partially filled with the precursor fluid (15); a step (E20) of providing a growth element (100) having a growth surface (s101); An arrangement step (E30) in which the growth surface (s101) is arranged opposite to the diffusion surface (s33) of the diffusion device (1); a pressurizing step (E50) of pressurizing the receiving enclosure (11) of the diffusion device (1) by setting the precursor fluid (15) at a pressure higher than the threshold pressure so that the precursor fluid (15) can pass through the thickness (e31) of the porous element (30) to generate an aerosol (17) by atomization of the precursor fluid (15) as it passes through the thickness (e31) of the porous element (30) and direct the aerosol (17) formed of droplets of the precursor fluid (15) towards the growth surface (s101); a growing step (E60) in which the aerosol (17) undergoes a chemical reaction on the growing surface (s101) to form the layer (103); A film forming method comprising:

13. The film forming method according to claim 12, The film forming method, wherein the placing step (E30) is performed before the pressing step (E50).

14. The film forming method according to claim 12, The film formation method, wherein at least one step selected from the placing step (E30), the pressurizing step (E50), and the growing step (E60) is carried out in a growth chamber of a chemical growth furnace, preferably in a growth chamber of a chemical vapor deposition furnace.

15. The film forming method according to claim 14, The film formation method, wherein the growth step (E60) is carried out in a chemical growth furnace such that the chemical growth furnace brings the growth chamber to a growth temperature, heats the growth member (100) and the diffusion device (1) at the growth temperature, and promotes a chemical reaction of the aerosol (17) on the growth surface (s101).

16. The film forming method according to claim 12, The film-forming method, wherein the preparation step (E10) of preparing the diffusion device (1) includes a step (E01) of manufacturing the porous element (30) by three-dimensional shaping.

17. The film forming method according to claim 12, A method of deposition comprising a filling step (E03) of introducing a precursor fluid (15) into at least one receiving enclosure (11) of the diffusion device (1).

18. A method for growing a layer (103) on a growth surface (s101), comprising: a preparation step (E10) in which a diffusion device (1) according to claim 6 is prepared, in which at least a part of said at least one receiving enclosure (11) is filled with said precursor fluid (15); a step (E20) of providing a growth element (100) having a growth surface (s101); An arrangement step (E30) in which the growth surface (s101) is arranged opposite to the diffusion surface (s33) of the diffusion device (1); a pressurizing step (E50) of pressurizing the receiving enclosure (11) of the diffusion device (1) by setting the precursor fluid (15) at a pressure higher than the threshold pressure so that the precursor fluid (15) can pass through the thickness (e31) of the porous element (30) to generate an aerosol (17) by atomization of the precursor fluid (15) as it passes through the thickness (e31) of the porous element (30) and direct the aerosol (17) formed of droplets of the precursor fluid (15) towards the growth surface (s101); a growing step (E60) in which the aerosol (17) undergoes a chemical reaction on the growing surface (s101) to form the layer (103); Including, the step (E20) of providing the growth element (100) comprises providing a generally tubular growth element (100) along a major axis (X2), the growth element (100) defining an internal cavity (107) open to the outside by an insertion opening (109) located at one end of the growth element (100) considered to be along the major axis (X2), the cavity (107) being formed in a third prismatic shape defining at least the growth surface (s101) and characterized by a third basic outer shape, the third prismatic shape being formed by a linear translation of the third basic outer shape along the major axis (X2), the third basic outer shape being a circle of radius (r3) greater than the first radius (r1); The method of forming a film, wherein the positioning step (E30) includes a step (E31) of inserting the diffusion device (1) into the cavity (107) of the growth member (100) through the insertion opening (109) along the major axis (X2).

19. 19. The film forming method according to claim 18, A film formation method in which the length (L1) of the porous element (30) measured along the longitudinal axis (X) of the container (10) is strictly greater than the length (L1) of the growth member (100) measured along the main axis (X2), and after step (E31) of inserting the diffusion device (1) inside the growth member (100), the entire growth surface (s101) faces at least a part of the outer surface of the porous element (30).

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