Device and method for depositing two-dimensional coating

Abstract

To provide a device with which several different two-dimensional coatings may be deposited adjacently, on top of each other or side by side.SOLUTION: A device for depositing a heterostructure including a first two-dimensional layer and a second two-dimensional layer, which are different from each other, on a substrate 4 includes: a CVD reactor 1 which has a process chamber 3 and a gas inlet member 2; a first bubbler 32 configured to supply a first transition metal compound; a first reactive gas source configured to supply a first reactive gas comprising a first element of main group VI; a second bubbler 32' configured to supply a second transition metal compound; a second reactive gas source configured to supply a second reactive gas comprising a second element of main group VI; inert gas sources 39, 39' configured to supply an inert gas and a diluent gas; first and second switch devices; and a control unit 29 configured to control switch valves 33, 33' of the first and second switch devices.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for depositing a two-dimensional coating on a substrate in a CVD reactor, in which a process gas is supplied through a supply line into a gas distribution chamber of a gas inlet member having gas outlet holes opening into the process chamber, in which the process gas or its decomposition products are brought into contact with the surface of a substrate, and in which the substrate is raised to a process temperature by a heating device, whereby the process gas in the process chamber chemically reacts such that a two-dimensional coating is deposited on the surface.

[0002] The present invention further relates to an apparatus for depositing a two-dimensional coating on a substrate using a CVD reactor, the CVD reactor comprising a gas inlet member with a supply line opening into a gas distribution chamber, a process chamber into which gas outlet holes of the gas distribution chamber open, a susceptor for heating the substrate by a heating device and supporting the substrate, wherein the supply line is connected to a gas mixing system, wherein at least one inert gas from an inert gas source or an inert gas from a dilution gas source and at least one reactive gas from a reactive gas source are supplied, wherein the reactive gas has properties that, when introduced into the heated process chamber, chemically react with each other so that a two-dimensional coating is deposited on the substrate.

[0003] The invention further relates to the use of a CVD reactor for depositing a two-dimensional coating on a substrate.

[0004] Patent document 1 describes the deposition of two-dimensional coatings using a CVD reactor, where the gas inlet member is a showerhead. The deposition of graphene using a CVD reactor in which a showerhead is used as the gas inlet member is known from Patent document 2. CVD reactors are known from Patent documents 3 to 11.

[0005] US Pat. No. 6,299,499 describes a showerhead with a gas outlet region that includes two gas outlet zones.

[0006] US Pat. No. 6,299,499 describes a showerhead with multiple gas distribution chambers arranged one on top of the other. US Patent No. 5,999,949 describes a method and apparatus for depositing two-dimensional coatings on a substrate, in which two different starting materials are successively deposited as monolayers on the surface of the substrate, such that the second monolayer initiates a self-radiative reaction with the first monolayer. Atomic layer deposition is also known from US Pat. No. 5,629,999. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] DE 10 2013 111 791 [Patent Document 2] International Publication No. 2017 / 029470 [Patent Document 3] DE 10 2011 056 589 A1 [Patent Document 4] DE 10 2010 016 471 A1 [Patent Document 5] DE 10 2004 007 984 A1 [Patent Document 6] DE 10 2009 043 840 A1 [Patent Document 7] DE 11 2004 001 026 [Patent Document 8] European Patent No. 1 255 876 [Patent Document 9] DE 10 2005 055 468 A1 [Patent Document 10] US Patent Application Publication No. 2006 / 0191637 [Patent Document 11] DE 10 2011 002 145 A1 [Patent Document 12] International Publication No. 2014 / 066100 [Patent Document 13] US Patent Application Publication No. 2010 / 119727 [Patent Document 14] DE 10 2013 101 534 A1 [Patent Document 15] DE 10 2009 043 840 A1 [Patent Document 16] DE 10 2007 026 349 A1 [Patent Document 17] US Patent Application Publication No. 2009 / 00661083 [Patent Document 18] US Patent Application Publication No. 2015 / 0170908 Summary of the Invention [Problem to be solved by the invention]

[0008] The underlying objective of the present invention is to describe a CVD reactor and associated method in which several different two-dimensional coatings can be deposited adjacent to each other, either on top of or alongside each other.

[0009] This object is solved by the invention as defined in the claims, the dependent claims showing advantageous further developments as well as independent solutions of this object.

[0010] The CVD reactor of the present invention includes two volumes separated from each other and each forming a gas distribution chamber. A first process gas can be supplied to the first gas distribution chamber. The process gas can be a gas mixture of several reactive gases, for example, two reactive gases. The process gas can preferably be only one reactive gas. This first reactive gas is used to deposit a first two-dimensional coating. The second gas distribution chamber is designed so that a second process gas can be supplied therein, thereby depositing a second two-dimensional coating therein. The second process gas can be different from the first process gas and can consist of one or more reactive gases. However, the second process gas can preferably consist of only one reactive gas. When depositing a multilayer structure, one process gas is supplied to one gas distribution chamber, and different process gases are supplied alternately to each of the other gas distribution chambers. Thus, each process gas can be a mixture of several reactive gases, in particular one reactive gas or in particular two reactive gases. Preferably, a process gas is supplied to only one of the several gas distribution chambers at any given time. In each case, the gas supplied to the other several gas distribution chambers is a diluent gas, which may be an inert gas, for example a noble gas such as argon, or a reducing gas such as hydrogen.

[0011] In the method of the present invention, the gas inlet member includes at least two gas distribution chambers separated from one another, each of which is supplied with a different gas or gas mixture through a separate supply line. However, the apparatus may also include more than two gas distribution chambers, each of which is supplied separately by a supply line. The gases exit simultaneously through different gas outlet holes, each of which is assigned to one of the gas distribution chambers. The CVD reactor of the present invention may include gas distribution chambers arranged vertically one above the other, each extending across the entire gas outlet surface of the gas inlet member. The gas outlet surface may have the shape of a disk, with the gas outlet holes arranged flat thereon.

[0012] The gas outlet holes are connected to multiple gas distribution chambers, with each hole communicating with one gas distribution chamber. Process gases can flow through the gas outlet holes into the process chambers of the CVD reactor, where chemical reactions occur to deposit a two-dimensional coating on the surface of the substrate. The substrate may be a sapphire substrate, a silicon substrate, or the like. Each gas distribution chamber communicates with a gas outlet face through multiple gas outlet holes, where the gas outlet holes are arranged substantially flat across the gas outlet face.

[0013] According to a first variant of the invention, an inert or dilution gas is fed into a first distribution chamber and a reactive gas is fed into a second gas distribution chamber, the reactive gas being decomposed either by pyrolysis or in other ways, in particular by the introduction of energy in the process chamber, the decomposition products then forming a two-dimensional coating on the substrate.

[0014] In a second alternative embodiment of the present invention, different reactive gases can be supplied to each gas distribution chamber. In the process chamber, the reactive gases can chemically react with each other to form a two-dimensional coating. In the first alternative embodiment, graphene or hBN is preferably deposited, where methane or borodin is used as the reactive gas. In the second alternative embodiment of the method, a transition metal gas, such as tungsten, molybdenum, or the like, can be supplied to one gas distribution chamber. A VI main group gas, such as sulfur, selenium, or tellurium, can be supplied to the second gas distribution chamber. The two-dimensional coating can be a transition metal chalcogenide. In a preferred embodiment, the CVD reactor has a gas outlet plate facing the process chamber, the back surface of which is adjacent to a cooling chamber through which a coolant flows. The first gas distribution chamber, to which the first gas is supplied, can be located above the cooling chamber. The gas distribution chamber is connected to the gas outlet surface of the gas outlet plate of the gas inlet member through a pipe that crosses the cooling chamber.

[0015] The first pipes are arranged laterally alternately with the second pipes, the first pipes connecting the first gas distribution chamber to the gas outlet surface, and the second pipes traverse both the cooling chamber and the first gas distribution chamber and connect the second gas distribution chamber located above the first gas distribution chamber to the gas outlet surface. Meanwhile, the gas outlet member may have a shape as described in Patent Documents 14 to 16. The entire contents of these documents are therefore incorporated by reference in their entirety.

[0016] The floor of the process chamber is formed by a susceptor, which can be heated by a heating device to a process temperature preferably above 1000°C. In a further alternative, a mixture of reactive gases can be supplied to one of the gas distribution chambers, for example, to deposit tungsten sulfide. The gas mixture can be composed of tungsten hexacarbonyl W(CO)6 and di-tert-butyl-sulfide S(C44H9)2. In one embodiment, a multilayer structure is deposited on a sapphire substrate, where the multilayer structure includes at least one coating or several coatings of hexagonal boron nitride (hBN), e.g., 5 nm thick. A graphene coating or multiple graphene coatings (multilayer graphene) can be deposited one on top of the other on top of each other. Similarly, an hBN coating, e.g., 3 nm thick, can be deposited on the graphene coating. [Brief explanation of the drawings]

[0017] In the following, the invention will be explained in more detail with reference to exemplary embodiments. [Figure 1] FIG. 1 is a schematic diagram of a CVD reactor with an associated gas mixing system. [Figure 2] FIG. 2 is an enlarged view of region II in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] 1 shows a CVD reactor 1 comprising an airtight housing in which a gas inlet member 2 is provided. A process chamber 3 is located below the gas inlet member 2, the floor of which forms a susceptor 5, which may be made of graphite or coated graphite. The susceptor 5 may be heated from below by a heating device 6, which may be a resistance heater, an infrared heater, or a high-frequency induction heater. A gas outlet member 7, connected to a vacuum pump (not shown), extends around the susceptor, which has a circular bottom. The gas outlet member 7 may surround the susceptor 5.

[0019] The upper side of the susceptor 5 facing towards the process chamber 3 comprises a support surface 15 on which the substrate 4 is supported, which may be made of sapphire, silicon, metal or the like.

[0020] The gas inlet member 2 has the shape of a showerhead. Inside the gas inlet member 2, there is a cooling chamber 8 between a gas outlet plate 9 and an intermediate plate 23. Above the cooling chamber 8, a gas distribution chamber 21 is provided between the intermediate plate 23 and the intermediate plate 13. Furthermore, a gas distribution chamber 11 is provided between the intermediate plate 13 and a cover plate 16.

[0021] A supply line 20, through which gases can be supplied from outside the CVD reactor, opens into a gas distribution chamber 21. A supply line 10, through which gases can be supplied from outside the CVD reactor 1, opens into a gas distribution chamber 11.

[0022] The gas distribution chamber 11 is connected to the process chamber 3 via a number of pipes 12 distributed in a uniform arrangement across the gas outlet face 25 of the gas outlet plate 9. The pipes 12 open into gas outlet holes 14 through which gas supplied to the gas distribution chamber 11 can flow into the process chamber 3.

[0023] The gas distribution chamber 21 is connected to a gas outlet surface 25 via a number of pipes 22 so that gases supplied to the gas distribution chamber 21 can flow through gas outlet holes 24 assigned to the pipes 22 into the process chamber.

[0024] The supply line 8' opens into the cooling chamber 8, and coolant can be supplied to the cooling chamber 8 through the supply line. The coolant can flow out of the cooling chamber 8 again through the discharge line 8''.

[0025] Reference numeral 19 denotes a pyrometer, by means of which the surface of the substrate 4 can be observed during growth, thus enabling the surface temperature to be measured. The optical beam path 18 of the pyrometer 19 passes through a window 17 in the cover plate 16 that is transparent to the wavelength of the pyrometer 19, and through one of the pipes 12.

[0026] The gas mixing system comprises a control unit 29, which may be a supervisory computer. Various mass flow controllers 30, 30'; 37, 37'; 41, 41' may be operated using the control unit 29. The control unit 29 may also be used to regulate the temperature of the thermal bath (thermostat). Sources 32, 32' of liquid or solid starting materials are arranged therein in the form of bubblers 32, 32'. Reference numerals 31, 31' denote concentration meters, by means of which the concentration of vapor in the carrier gas stream can be measured. Reference numerals 39, 39' denote inert or diluent gas sources, which respectively provide inert or diluent gases, e.g., noble or reducing gases, e.g., hydrogen or mixtures thereof. Reference numerals 40, 40' denote sources of reactive gases, e.g., methane or other hydrocarbons.

[0027] Reference numerals 33, 33' indicate switching valves by means of which vapors generated in bubblers 32, 32' and carried by the carrier gas can be sent to a vent line 35 which bypasses the CVD reactor 1 or fed to one of the supply lines 10, 20 through flow lines 34, 34'.

[0028] The bubblers 32, 32' can be used to generate reactive gas. For this purpose, an inert or diluent gas from a source 39, 39' is supplied to the bubblers 32, 32' via a mass flow controller 30, 30'. The vapor concentration in the carrier gas flow can be measured downstream therefrom using a concentration meter 31, 31'. Before the reactive gas is supplied to the gas inlet member 2, the reactive gas is sent to the vent line 35 until the gas flow is stable. To begin depositing the two-dimensional coating, the switching valves 33, 33' are switched so that a stable gas flow can be supplied to one of the gas distribution chambers 11, 21 through the flow line 34, 34'. In the exemplary embodiment, two sources are shown, whereby the reactive gas can be generated from a powder or a liquid, respectively. In embodiments not shown, multiple sources of this type can be provided.

[0029] If no reactive gas is supplied to one of the gas distribution chambers 11, 21, an inert or diluent gas from an inert or diluent gas source can be supplied to the gas distribution chambers 11, 21 via valves 36, 36' and mass flow controllers 37, 37'.

[0030] Alternatively, however, starting materials available in gaseous form, such as methane or other hydrocarbons, may be drawn from gas sources 40, 40' and delivered via mass flow controllers 41, 41' to gas distribution chambers 11, 21. Borazine may be delivered from the gas source if it is available above its boiling point; otherwise, borazine may be delivered as a gas or vapor via bubblers 32, 32'.

[0031] To deposit a multilayer structure, a reactive gas or a mixture of two reactive gases is supplied to one of the gas distribution chambers 11, 21, and alternately, an inert gas or a diluent gas is supplied to the other gas distribution chamber 11, 21. In this way, multilayer structures of hBN and graphene can be deposited sequentially, for example, by switching between borazine and methane flows. A graphene coating or multilayer graphene coating can be incorporated between two hBN coatings, particularly monolayer coatings. Alternatively, however, lateral heterostructures can be deposited, in which various two-dimensional coatings are deposited side by side on the substrate surface or on the surface of a previously deposited coating. Coatings deposited alongside one another may be interconnected.

[0032] Alternatively, a first starting material may be supplied to a first gas distribution chamber 11, 21 and a second starting material may be supplied to a second gas distribution chamber 11, 21, or a process gas that is a mixture of two reactive gases may be supplied to one of the gas distribution chambers. For example, one of the reactive gases may be tungsten hexacarbonyl sene, which may be obtained via a bubbler 32, 32'. The other reactive gas may be a compound with sulfur, tellurium, or selenium. Thus, the starting materials may be supplied either to different gas distribution chambers 11, 21 or to the same gas distribution chamber 11, 21.

[0033] The present invention relates to all combinations of substances mentioned in WO 2005 / 024990. To this end, the entire disclosure of that document is also incorporated into the present application.

[0034] The foregoing is intended to serve as a description of an invention within the full scope of this application, which also independently advances the relevant art through at least the combination of the following features, and which may also combine two, more, or all of said combinations of features.

[0035] 1. A method according to claim 1, wherein the gas inlet member (2) comprises at least two gas distribution chambers (11, 21) which are separated from one another and which are supplied by one supply line (10, 20) with gases or gas mixtures which exit from mutually different and simultaneously gas outlet holes (14, 24), the gas outlet holes (14, 24) being mutually different and each assigned to one of the gas distribution chambers (11, 21).

[0036] 1. A method according to claim 1, wherein the gas inlet member (2) comprises at least two gas distribution chambers (11, 21) which are separated from one another and to which different gases or gas mixtures are supplied via one supply line (10, 20) respectively, which gases or gas mixtures exit simultaneously through gas outlet holes (14, 24), the gas outlet holes (14, 24) being different from one another and each assigned to one of the gas distribution chambers (11, 21).

[0037] 1. A method or use characterized in that an inert gas or a diluent gas is supplied to the first gas distribution chamber (11) and a reactive gas or a gas mixture of gases containing elements of which the two-dimensional coating is composed is supplied to the second gas distribution chamber (21), the reactive gas being decomposed, for example by pyrolysis, in the process chamber (3), whereby the decomposition products form the two-dimensional coating, or different reactive gases are supplied to the gas distribution chambers (11, 21) and chemically react with each other in the process chamber (3) so as to form the two-dimensional coating.

[0038] 1. A method or use characterized in that in a first step, on a first two-dimensional coating is deposited, during its deposition an inert or diluent gas is supplied through the first gas distribution chambers 11 and 20 and the gas outlet holes 14 assigned thereto, and a first reactive gas or gas mixture, in particular comprising a gas containing elements of the two-dimensional coating, is supplied through the second gas distribution chamber 21 and the gas outlet holes 24 assigned thereto into the process chamber, and in a second step a second two-dimensional coating is deposited, during its deposition a second reactive gas different from the first reactive gas is supplied through the first gas distribution chamber 1 and the gas outlet holes 14 assigned thereto, and an inert or diluent gas is supplied through the second gas distribution chamber 21 and the gas outlet holes 24 assigned thereto into the process chamber, in which case, in particular, two steps are provided to be carried out one or more times.

[0039] 1. A method or use characterized in that mutually different two-dimensional coatings are deposited one on top of the other in a number of successive steps, in which the reactive gases used therefor are supplied to different gas distribution chambers (11, 21), in particular alternately.

[0040] 1. An apparatus characterized in that the gas inlet member 2 comprises two gas distribution chambers 11, 21 which are separated from one another and each provided with a supply line 10, 20, wherein each of the two supply lines 10, 20 can be freely connected to one of an inert gas source, a diluent gas source or a reactive gas source.

[0041] A method, use or apparatus characterized in that the devices 33, 33'; 36, 36'; 38, 38' can be switched so that one of the inert or dilution gas sources 39, 39' or reactive gas sources 32, 32'; 40, 40' can be freely and alternately brought into communication with the gas distribution chamber 11, 21.

[0042] A method, use, or apparatus characterized in that a reactive gas source 32, 32' is freely or alternatively connected to a vent line 35 to bypass or deliver past the process chamber, or to a flow line 34, 34' to allow reactive gas to be introduced into the process chamber.

[0043] the gas inlet member 2 is a showerhead with a gas outlet surface 25, in which the gas outlet holes 14, 24 are arranged, in which two gas distribution chambers 11, 21 separated from each other by an intermediate plate 13 are arranged, each connected by a pipe 12, 12', 22 to the gas outlet holes 14, 24 that are uniformly arranged over the gas outlet surface 25; and / or the material of the two-dimensional coating is graphene, hBN or a transition metal dichalcogenide, in particular MoS2, WS2, MoSe2 or WSe2; and / or 1. A method, use or apparatus comprising the steps of: (a) providing a first reactive gas or a reactive gas mixture containing a hydrocarbon compound, for example methane, or a boron compound, for example borazine; and / or (b) providing a first reactive gas which is an element of a transition metal, in particular a molybdenum compound or tungsten, and a second reactive gas which contains an element of group VI and is in particular a sulfur compound, for example di-tert-butyl-sulfide, a selenium compound or a tellurium compound; and / or (c) providing an inert gas which is a noble gas, for example argon, and a diluent gas which is a reducing gas, for example hydrogen.

[0044] All disclosed features are essential to the invention (both by themselves and in combination with one another). The disclosure of the present application includes in its entirety the disclosure content of the relevant / attached priority documents (copies and earlier applications), also for the purpose of incorporating the features of these documents into the claims of the present application. The dependent claims are characterized by an independent, inventive further development of the prior art, even without the features of the claims cited therein, in particular for the purpose of filing a divisional application based on these claims. The invention specified in each claim may additionally have one or more features specified in the preceding description, in particular those given reference signs and / or specified in the sign explanations. The present invention also relates in particular to embodiments in which individual features set forth in the preceding description are not implemented, insofar as they are clearly unnecessary for the respective intended use or can be replaced by other means having the same technical effect. [Explanation of symbols]

[0045] 1 CVD reactor 2 Gas inlet member 3. Process chamber 4 boards 5 Susceptor 6 Heating device 7 Gas outlet member 8 Cooling Chamber 8' supply line 8" discharge line 9 Gas Outlet Plate 10 Supply Line 11 Gas distribution chamber 12 Pipes 12' pipe 13 Intermediate plate 14 Gas outlet hole 15 Support surface 16 Cover Plate 17 Windows 18 Beam Path 19 Optical devices, pyrometers 20 Supply Line 21 Gas distribution chamber 22 Gas inlet member 23 Intermediate plate 24 Gas outlet hole 25 Gas outlet surface 29 Control Device 30 Mass Flow Controller 30' Mass Flow Controller 31 Concentration meter 31' Concentration Meter 32 Bubbler 32' Bubbler 33 Switching valve 33' Switching Valve 34 Flow Line 34' flow line 35 Ventilation line 37 Mass Flow Controller 37' Mass Flow Controller 39 Inert Gas Source 39' Inert gas source 40 Reactive Gas Source 40' reactive gas source 41 Mass Flow Controller 41' Mass Flow Controller TP Process Temperature

Claims

1. 1. An apparatus for depositing a heterostructure comprising a first two-dimensional layer and a second two-dimensional layer that are different from each other on a substrate (4), comprising: a CVD reactor (1) comprising a process chamber (3) and a gas inlet member (2), the gas inlet member (2) comprising a first gas distribution chamber (11) and a second gas distribution chamber (21) separated from the first gas distribution chamber (11), the first gas distribution chamber (11) and the second gas distribution chamber (21) being arranged vertically relative to one another, and respective gas outlet holes (14) communicating with the first gas distribution chamber (11) and respective gas outlet holes (24) communicating with the second gas distribution chamber (21) being uniformly arranged over the entire gas outlet surface (25) of the gas inlet member (2); a first bubbler (32) configured to supply a first transition metal compound and a first reactive gas source configured to supply a first reactive gas comprising a first element of main group VI, wherein the first transition metal compound is capable of reacting with the first reactive gas to form the first two-dimensional layer of a first metal dichalcogenide on the substrate (4); a second bubbler (32') configured to supply a second transition metal compound and a second reactive gas source configured to supply a second reactive gas comprising a second element of main group VI, wherein the second transition metal compound is capable of reacting with the second reactive gas to form the second two-dimensional layer of a second metal dichalcogenide on the substrate (4); an inert gas source (39, 39') configured to supply an inert gas and a diluent gas; The first bubbler (32) and the second bubbler (32') have first and second switching devices configured to alternately connect to a vent line (35) through which the first transition metal compound or the second transition metal compound bypasses the process chamber (3) or to a first flow line (34) and a second flow line (34') through which the first transition metal compound and the second transition metal compound are introduced into the first gas distribution chamber (11) or the second gas distribution chamber (21), respectively; The device comprises a control unit (29) configured to control the switching valves (33, 33') of the first switching device and the second switching device.

2. supplying the first transition metal compound to the first gas distribution chamber (11) while supplying the first reactive gas to the second gas distribution chamber (21), wherein the substrate (4) is heated to a first process temperature to form the first two-dimensional layer, which is the first metal dichalcogenide, on a surface of the substrate (4); 2. The apparatus of claim 1, wherein the control unit (29) is configured to perform the steps of: supplying the inert gas or the dilution gas to a second gas distribution chamber (21) while supplying the second reactive gas to the first gas distribution chamber (11), and wherein the substrate (4) is heated to a second process temperature to form the second two-dimensional layer, which is the second metal dichalcogenide, on a surface of the substrate (4).

3. supplying the first transition metal compound to the first gas distribution chamber (11) while supplying the first reactive gas to the second gas distribution chamber (21), wherein the substrate (4) is heated to a first process temperature to form the first two-dimensional layer, which is the first metal dichalcogenide, on a surface of the substrate (4); supplying the inert gas or the dilution gas into a second gas distribution chamber (21) while supplying the second reactive gas into the first gas distribution chamber (11), wherein the substrate (4) is heated to a second process temperature to form the second two-dimensional layer of the second metal dichalcogenide on a surface of the substrate (4), 3. A method of using the device according to claim 1 or 2.

4. 3. The apparatus of claim 1 or 2, wherein the first bubbler (32) comprises a molybdenum compound.

5. 4. The apparatus of claim 2 or 3, wherein the second bubbler (32') comprises a tungsten compound.

6. 1. An apparatus for depositing a heterostructure comprising a first two-dimensional layer and a second two-dimensional layer that are different from each other on a substrate (4), comprising: a CVD reactor (1) comprising a process chamber (3) and a gas inlet member (2), the gas inlet member (2) comprising a first gas distribution chamber (11) and a second gas distribution chamber (21) separated from the first gas distribution chamber (11), the first gas distribution chamber (11) and the second gas distribution chamber (21) being arranged vertically relative to one another, and respective gas outlet holes (14) communicating with the first gas distribution chamber (11) and respective gas outlet holes (24) communicating with the second gas distribution chamber (21) being uniformly arranged over the entire gas outlet surface (25) of the gas inlet member (2); a first reactive gas source (40) configured to supply a first reactive gas, the first reactive gas being a hydrocarbon compound; a second reactive gas source (40') configured to supply a second reactive gas, the second reactive gas being borazine; an inert gas source (39, 39') configured to supply an inert gas or a diluent gas; a control unit (29) configured to control the valves (38, 38').

7. supplying the inert gas or the dilution gas into the first gas distribution chamber (11) while supplying the first reactive gas into the second gas distribution chamber (21), wherein the substrate (4) is heated to a first process temperature to form the first two-dimensional layer, which is graphene, on a surface of the substrate (4) from decomposition products of the first reactive gas; 7. The apparatus of claim 1, wherein the control unit (2) is configured to perform the steps of: supplying the inert gas or the dilution gas to the second gas distribution chamber (21) while supplying the second reactive gas to the first gas distribution chamber (11), and wherein the substrate (4) is heated to a second process temperature to form the second two-dimensional layer, which is hexagonal boron nitride (hBN), on the surface of the substrate (4) from decomposition products of the second reactive gas.

8. supplying the inert gas or the dilution gas into the first gas distribution chamber (11) while supplying the first reactive gas into the second gas distribution chamber (21), wherein the substrate (4) is heated to a first process temperature to form the first two-dimensional layer, which is graphene, on a surface of the substrate (4) from decomposition products of the first reactive gas; supplying the inert gas or the dilution gas into the second gas distribution chamber (21) while supplying the second reactive gas into the first gas distribution chamber (11), wherein the substrate (4) is heated to a second process temperature to form the second two-dimensional layer of hexagonal boron nitride (hBN) on the surface of the substrate (4) from decomposition products of the second reactive gas, 7. A method of using the device of claim 6.

9. 1. An apparatus for depositing a heterostructure comprising a first two-dimensional layer and a second two-dimensional layer that are different from each other on a substrate (4), comprising: a CVD reactor (1) comprising a process chamber (3) and a gas inlet member (2), the gas inlet member (2) comprising a first gas distribution chamber (11) and a second gas distribution chamber (21) separated from the first gas distribution chamber (11), the first gas distribution chamber (11) and the second gas distribution chamber (21) being arranged vertically relative to one another, and respective gas outlet holes (14) communicating with the first gas distribution chamber (11) and respective gas outlet holes (24) communicating with the second gas distribution chamber (21) being uniformly arranged over the entire gas outlet surface (25) of the gas inlet member (2); a first reactive gas source (40) configured to supply a first reactive gas; a second reactive gas source (40') configured to supply a second reactive gas; an inert gas source (39, 39') configured to supply an inert gas or a diluent gas; The apparatus, wherein the first reactive gas source (40) and the second reactive gas source (40') are configured to supply reactive gases that, in a chemical reaction, form a metal dichalcogenide, graphene, or hexagonal boron nitride (hBN).

10. 10. The apparatus of claim 9, wherein the first reactive gas source (40) and the second reactive gas source (40') comprise bubblers (32, 32') configured to deliver a transition metal compound.

11. The apparatus of claim 10, wherein the bubbler (32, 32') comprises a molybdenum compound or a tungsten compound.

12. a first switching device and a second switching device configured to alternately connect the first bubbler (32) and the second bubbler (32') to a vent line (35) through which the first transition metal compound or the second transition metal compound bypasses the process chamber (3) or to a first flow line (34) and a second flow line (34') through which the first transition metal compound and the second transition metal compound are introduced into the first gas distribution chamber (11) or the second gas distribution chamber (21), respectively; 12. The device according to claim 9, 10 or 11, further comprising a control unit (29) configured to control the valves (38, 38') of the first and second switching devices.

13. 13. The apparatus of claim 9 or 12, wherein at least one of the first reactive gas source (40) and the second reactive gas source (40') is configured to provide a hydrocarbon or borazine.

Images