Simultaneous growth of two silicon carbide layers

Abstract

A system (100) for simultaneously generating first and second epitaxial single crystal layers on each of the first and second substrates is provided, comprising: a first inner container (3) defining a first cavity for accommodating a first source material and a first substrate; a second inner container (4) defining a second cavity for accommodating a second source material and a second substrate; an insulating container (6) arranged to accommodate the first and second inner containers (3, 4) inside; an outer container (7) arranged to accommodate the insulating container (6) and the first and second inner containers (3, 4) inside; and a heating means (8) arranged outside the outer container (7) and configured to simultaneously heat the first and second cavities.

Description

Technology Field

[0001] The present invention generally relates to a system and method for the sublimation growth of a single-crystal silicon carbide layer. Specifically, it relates to a system and method for simultaneously growing two epitaxial single-crystal silicon carbide layers. Background Technology

[0002] Recently, there has been an increasing demand for improved energy efficiency in electronic devices capable of operating at high power levels and high temperatures. Silicon (Si) is currently the most commonly used material in semiconductors for power devices, and silicon carbide (SiC) is a very suitable material due to its high thermal conductivity, high saturation electron drift velocity, and high breakdown electric field strength.

[0003] The most common technique used to grow single-crystal SiC layers by sublimation is physical vapor transport (PVT). In this technique, a seed crystal on which the single-crystal layer is to be grown and a source material are placed in a crucible and heated to the sublimation temperature of the source material, which is often in powder form. Vapor species from the source material are subsequently deposited onto the seed crystal upon which the single-crystal layer can be grown. However, using powder as a source material has several disadvantages. Powder often contains impurities as a result of the manufacturing process. Additionally, the heat distribution of the powder may not be sufficiently homogeneous, which can lead to poor control of the powder's sublimation. Another disadvantage is the risk that solid particles of the powder may fall onto the seed, causing inclusions and impurities in the final crystal structure.

[0004] The PVT version is a sublimation sandwich method (SSM) in which monolithic SiC plates are used as the source material instead of powder. For example, using plates helps control the temperature uniformity of the source material. Another advantage of this method is the positive effect that the gaseous paper does not react with the crucible walls because the distance between the source material and the seed crystal / substrate is short.

[0005] However, this process is still time-consuming and is not suitable for producing more than one single crystal at a time. As the demand for SiC single crystals increases, there is a growing need to increase production capacity and efficiency while maintaining or improving quality. A system for growing one or more SiC single crystals simultaneously is disclosed in European patent application EP 2664695 A1. Two single crystals are produced in two growth compartments, respectively, and the source material is contained in a single compartment that supplies both growth compartments. Additionally, the source material is in powder form.

[0006] Therefore, improved systems and methods are still needed to overcome at least some of the problems described above.

[0007] The system and method described herein overcome this problem by providing a system for simultaneously creating first and second epitaxial single crystal layers on each of the first and second substrates, comprising: a first inner container defining a first cavity for accommodating a first source material and a first substrate; a second inner container defining a second cavity for accommodating a second source material and a second substrate; an insulating container disposed to accommodate the first and second inner containers inside; an outer container disposed to accommodate the insulating container and the first and second inner containers inside; and heating means disposed outside the outer container and configured to simultaneously heat the first and second cavities.

[0008] The production capacity can be doubled by providing two containers that define two cavities placed inside the same insulating container. Since two single-crystal layers can be produced using one system, the energy consumption per produced layer is reduced by at least 50%.

[0009] In one embodiment of the present disclosure, a heating element is further provided within an insulating container, disposed between a first inner container and a second inner container, and a heating means is further configured to heat the heating element and the first and second cavities simultaneously.

[0010] The heating element generally functions as a heat reservoir that distributes heat evenly and simultaneously to the system, particularly to the first and second cavities. With this arrangement, a single heating element is sufficient to heat two cavities, so energy efficiency is higher and energy consumption can be reduced.

[0011] In one embodiment of the present disclosure, a first inner container, a second inner container, and a heating element are integrally formed.

[0012] In one embodiment of the present disclosure, the first inner container is placed on top of the second inner container. Additionally, the first and second inner containers are cylindrical in shape and have the same diameter.

[0013] In one embodiment of the present disclosure, a first inner container comprises an upper portion and a bottom portion, and a second inner container comprises an upper portion and a bottom portion, wherein the bottom portion of the first inner container is essentially the same as the upper portion of the second inner container.

[0014] There is an advantage that the heat drop inside the two cavities becomes equal as the bottom of the first inner container and the top of the second inner container become essentially the same.

[0015] One embodiment of the present disclosure includes a first means for placing a first source material at a predetermined distance from a first substrate within a first cavity and a second means for placing a second source material at a predetermined distance from a second substrate within a second cavity.

[0016] By controlling the distance between the source material and each substrate, it is ensured that two single-crystal layers grow uniformly at the same time.

[0017] In one embodiment of the present disclosure, a first source material is disposed below a first substrate, and a second source material is disposed above a second substrate.

[0018] This arrangement is particularly useful when the first inner vessel is positioned above the second inner vessel to provide the first and second source materials closer to the center of the system. Additionally, if a heating element is placed between the inner vessels, the source material is brought closer to the heating element, so the initial temperature rise becomes sufficiently rapid to reach the sublimation temperature sufficiently quickly.

[0019] In one embodiment of the present disclosure, the insulating container and the outer container are cylindrical in shape, and the first and second source materials and the first and second substrates are disk-shaped.

[0020] One embodiment of the present disclosure further includes first and second carbon getters disposed inside each of the first and second inner containers.

[0021] In one embodiment of the present disclosure, the heating means can move along the outer container.

[0022] These features provide the effect of allowing the temperature and heat drop inside the first and second cavities to be adjusted.

[0023] Additionally, the object of the present disclosure is to provide a method for simultaneously forming first and second epitaxial single crystal layers on respective first and second substrates, comprising: providing a first inner container defining a first cavity for receiving a first source material and a first substrate; providing a second inner container defining a second cavity for receiving a second source material and a second substrate; disposing of the first source material and the first substrate in the first cavity and disposing of the second source material and the second substrate in the second cavity; disposing of the first and second inner containers within an insulating container; disposing of the insulating container within an outer container and providing a heating means outside the outer container to simultaneously heat the first and second cavities; emptying the first and second cavities to a predetermined pressure; introducing an inert gas into the first and second cavities; and simultaneously raising the temperature of the first and second cavities to a predetermined growth temperature by the heating means. It includes maintaining a predetermined growth temperature in the first and second cavities until a predetermined thickness of the first and second epitaxial single crystal layers on each of the first and second substrates is achieved; and cooling the first and second substrates.

[0024] By providing first and second inner containers and arranging both within the same insulating container, and by heating both using the same heating means, two epitaxial single-crystal layers can be manufactured simultaneously in one system. Production is more energy-efficient, space-efficient, and production time is reduced.

[0025] In one embodiment of the present disclosure, the first and second source materials are monolithic silicon carbide.

[0026] In one embodiment of the present disclosure, placing a first source material and a second source material and a first substrate and a second substrate in each of the first cavity and the second cavity comprises the steps of placing a first source material below a first substrate and placing a second source material on a second substrate.

[0027] In one embodiment of the present disclosure, placing a first and second inner container within an insulating container includes placing a first inner container on top of a second inner container.

[0028] One embodiment of the present disclosure further includes providing a heating element between a first inner container and a second inner container.

[0029] In one embodiment of the present disclosure, raising the temperature of the first and second cavities further includes simultaneously raising the temperature of a heating element disposed between the first and second inner containers. Brief explanation of the drawing

[0030] The present invention is now described by way of example with reference to the attached drawings: FIG. 1 illustrates a system according to the present disclosure. FIGS. 2a-2d illustrates the upper and lower portions of an inner container according to the present disclosure. FIG. 3 illustrates a heating element according to the present disclosure. FIG. 4 illustrates a first internal container arrangement according to the present disclosure. FIG. 5 illustrates a carbon getter according to the present disclosure. FIG. 6 illustrates a second internal container arrangement according to the present disclosure. FIG. 7 illustrates an insulating container according to the present disclosure. FIG. 8 illustrates the process flow of the method according to the present disclosure. Specific details for implementing the invention

[0031] A detailed description of a system (100) and a method for simultaneously generating two SiC single-crystal layers using an SSM will be described below with reference to the attached drawings. The configuration of the system (100) and method described herein is configured to simultaneously generate two essentially identical SiC single-crystal layers, and the space required in the system for generating each SiC single-crystal layer is minimized. The SiC single-crystal layers may be identical in terms of, for example, size / dimensions and quality, wherein quality may be measured, for example, by the number of carbon inclusions and dislocation density or stress within the crystal. For example, stress may be caused by warping. The quality of the SiC single-crystal layers generated using the system and method disclosed herein is further improved compared to using existing systems and generation methods.

[0032] In FIG. 1, a system (100) for simultaneously generating two SiC single crystal layers is shown and generally includes a first inner container (3), a second inner container (4), a heating element (5), an insulating container (6), an outer container (7), and a heating means (8).

[0033] The first inner container (3) defines a first cavity arranged to accommodate a first source material (1a) and a first substrate (1b), and the second inner container (4) defines a second cavity arranged to accommodate a second source material (2a) and a second substrate (2b).

[0034] The arrangement of the heating element (5) and the first and second inner containers (3, 4) is mirror-symmetric with respect to a symmetry plane that divides the heating element (5) into two equal parts, which is indicated by a dashed line in FIG. 1. For example, the distance between the heating element (5) and the first source material (1a) in the first inner container (3) is equal to the distance between the heating element (5) and the second source material (2a) in the second inner container (4). Also, the distance between the first source material (1a) and the first substrate (1b) is equal to the distance between the second source material (2a) and the second substrate (2b). Thermal properties provided by the system (100), such as temperature, heat drop, and heating rate, are essentially the same in the first cavity and the second cavity. Accordingly, the growth properties for the two SiC single crystal layers grown on the respective first and second substrates (1b, 2b) within the first and second inner containers (3, 4) are essentially the same. The result is two essentially identical SiC single-crystal layers.

[0035] In the embodiment illustrated in FIG. 1, the first inner container (3), the second inner container (4), and the heating element (5) are all placed within an insulating container (6). The insulating container (6) is placed within an outer container (7). A heating means (8) is placed externally and surrounds the outer container (7). The heating means (80) is positioned to simultaneously heat the first and second cavities and the heating element (5) so that the first and second source materials (1a, 2a) sublimate during use, causing a single crystal layer to grow on the first and second substrates (1b, 2b). In the embodiment illustrated in FIG. 1, the heating means (8) is an induction coil for radio frequency heating. Additionally, since the heating means (8) is movable along the height direction of the outer container (7), it has the effect of being adjustable so that the temperature and heat drop inside the first and second cavities are equal.

[0036] The system (100) further includes a pump for emptying the first and second inner containers (3, 4). The pump empties 10 cavities of the first and second inner containers (3, 4). 4 mbar and 10 6 It can provide pressure between mbar.

[0037] In the embodiment illustrated in FIG. 1, the first inner container (3) is placed on top of the second inner container (4), and the heating element (5) is placed between the first and second inner containers (3, 4) and comes into contact with them. In another embodiment, the heating element (5) is formed integrally with the first and second inner containers (3, 4). In another embodiment, the heating element (5) is formed integrally with the bottom portion (31b) of the first inner container (3) and the top portion (32a) of the second inner container. The inner containers (3, 4) and the heating element (5) may be formed, for example, by high-density graphite. Additionally, the heating element (5) may be coated. This configuration maximizes the number of SiC single-crystal layers that can be produced per unit of height in the system (100).

[0038] In the embodiment illustrated in FIG. 1, the second inner container (4) is placed on two container supports (9). The supports are seated on the bottom of the insulating container (6) and have a height such that when the inner containers (3, 4) and the heating element (5) are placed on the supports (9), the upper surface of the first inner container (3) is spaced apart from the top of the insulating container (6). Additionally, the supports (9) may have a height such that the bottom surface of the second inner container (4) is spaced apart from the bottom portion of the insulating container (6), which is equal to the distance between the upper surface of the first inner container (3) and the top of the insulating container (6). In another embodiment, the two container supports (9) may be a single container support or multiple container supports. The container supports (9) must be formed of a material that withstands high temperatures, preferably a high-melting-point metal such as high-density graphite or tantalum.

[0039] FIGS. 2A and 2B illustrate a first inner container (3). The first inner container (3) has a cylindrical shape and includes an upper portion (3a) and a bottom portion (3b). In the embodiment of FIGS. 2A and 2B, the bottom edge of the upper portion (3a) is inclined inward, and the upper edge of the bottom portion (3b) is inclined outward in the same way, so that when the upper portion (3a) and the bottom portion (31b) are mounted, the parts can be joined together without moving sideways. The upper portion (3a) and the bottom portion (3b) define a first cavity arranged to accommodate the first source material (1a) and the first substrate (1b) when fitted together, which will be described in more detail in relation to FIG. 4. The first inner container (3) may be formed of high-density graphite or other suitable material capable of withstanding high temperatures, and when a radio frequency induction coil is used as a heating means (8), this facilitates coupling with said radio frequency induction coil.

[0040] FIGS. 2C and FIGS. 2D illustrate a second inner container (4). The second inner container (4) has a cylindrical shape and includes an upper portion (4a) and a bottom portion (4b). The upper portion (4a) is essentially identical to the bottom portion (3b) of the first inner container (3). The bottom portion (4b) is essentially identical to the upper portion (3a) of the first inner container (3). Additionally, the second inner container (4) has an outer diameter and an inner diameter that are essentially identical to the outer diameter and inner diameter of the first inner container (3). Thus, the first and second inner containers are mirror-symmetric with respect to the heating element (5) when placed above and below the heating element (5). The upper portion (4a) and the bottom portion (4b) define a second cavity that is positioned to accommodate the second source material (2a) and the second substrate (2b) when fitted together, which will be described in more detail in relation to FIG. 6. The second inner container (4) may be formed of high-density graphite or other suitable material capable of withstanding high temperatures, and when a radio frequency induction coil is used as a heating means (8), this facilitates coupling with the radio frequency induction coil.

[0041] FIG. 3 illustrates a heating element (5). As mentioned in relation to FIG. 1, the heating element (5) is positioned above the second inner container (4) and below the first inner container (3), and is in contact with both the first and second inner containers (3, 4). The heating element (5) has the function of distributing heat to the first and second inner containers (3, 4) so ​​that the temperature distribution of the first and second cavities can be essentially the same by heating the first and second inner containers (3, 4) simultaneously. The heating element (5) is formed as a solid body having an essentially cylindrical shape. The diameter of the heating element (5) is preferably 50 to 150% of the outer diameter of the first and second inner containers (3, 4), and more preferably 70 to 110%. The height of the heating element (5) is preferably 2 to 4 times greater than the thickness of the bottom portion (3b) of the first inner container (or the top portion (4a) of the second inner container (4)), and more preferably 2.5 to 3 times greater. Since only one of the heating elements (5) is required to heat both the first cavity and the second cavity, the total height of the system can be reduced compared to the case where the first cavity and the second cavity each require one heating element (5). Thus, the number of SiC single crystal layers generated per unit of height of the system is maximized.

[0042] FIG. 4 illustrates the arrangement of a first source material (1a) and a first substrate (1b) within a first inner container (3). It is preferable that the diameter of the first source material (1a) be larger than the diameter of the first substrate (1b). For example, the diameter of the first substrate (1b) may be 150 mm, and the first source material (1a) may have a diameter of 160 mm. The first source material (1a) is placed on at least one first source material support (10a) placed on the bottom portion (3b) of the first inner container (3). Thus, the first source material (1a) is placed at a certain distance from the bottom portion (3b) of the first inner container (3). The first source material (1a) may be, for example, a monolithic polycrystalline SiC plate having a cylindrical microparticle structure. Other microstructures are also possible. At least one first substrate support (10b) is placed on the first source material (1a) and supports the first substrate (1b) placed above and spaced apart from the first source material (1a). It should be understood that the closer to the top (3a), the further it is from the heating element (5). The distance between the first source material (1a) and the first substrate (1b) is preferably 0.7 to 1.2 mm. At least one first substrate support (10b) may be, for example, in the shape of a cube. Additionally, there may be three substrate supports (10b) placed on the outer edge of the first source material (1a), for example. In the embodiment illustrated in FIG. 4, a first carbon getter (11) is placed on the bottom portion (3b) of the first inner container (3), which will be described in more detail with reference to FIG. 5.

[0043] FIG. 5 illustrates a first carbon getter (11). The carbon getter (11) has a ring shape having an outer diameter that is essentially equal to or slightly smaller than the inner diameter of the first inner container (3). For example, if the inner diameter of the first inner container (3) is 200 mm, the outer diameter of the first carbon getter (11) may be 198 mm. Since the inner diameter of the carbon getter (11) is larger than the diameter of the first source material (1a), the first carbon getter (11) can surround the first source material (1a). For example, if the first source material (1a) has a diameter of 160 mm, the first carbon getter (11) may have an inner diameter of 170 mm. The first source support (10a), the first substrate support (10b), and the carbon getter (11) are all formed of a material having a melting point of 2200°C or higher and capable of reacting with carbon species evaporated from the source material to form a carbide layer. Such materials may be tantalum, niobium, and tungsten, but are not limited thereto. In another embodiment, the first carbon getter (11) comprises a plurality of parts. The plurality of parts may be formed of the same or different materials.

[0044] FIG. 6 illustrates the arrangement of a second source material (2a) and a second substrate (2b) within a second inner container (4). The diameter of the second source material (2a) is larger than the diameter of the second substrate (2b). For example, the second substrate (2b) may have a diameter of 150 mm, and the second source material (2a) may have a diameter of 160 mm. The second substrate (2b) is placed on at least one second substrate support (12b). At least one second substrate support (12b) is placed on the bottom portion (4b) of the second inner container (4). The second substrate (2b) can be seen as being arranged in a manner similar to how the first source material (1a) is arranged in the first inner container (3). The second source material (2a) is placed on at least one second source support (12a). At least one second source support (12a) is also positioned on the bottom portion (4b) and also positioned outside of at least one second substrate support (12b), where the outside should be understood as being further from the central axis of the second inner container (4). The height of at least one second source support (12a) is greater than the height of at least one second substrate support (12b), so that when the second source material (2a) is placed on at least one second source support (12a), the second source material (2a) can be placed on the upper portion of the second substrate (2b). Here, the above should be understood as being closer to the upper portion (4a) and closer to the heating element (5). For example, the internal height of the second inner container (4) may be 20 mm, the height of at least one second source support (12a) may be 17 mm, and the height of at least one second substrate support (12b) may be such that the second substrate (2b) is placed at a 1 mm interval below the second source material (2a). The second source material (2a) may be, for example, a monolithic polycrystalline SiC plate having a cylindrical microparticle structure and must also be essentially the same as the first source material (1a). Other microstructures for the second source material (2a) are possible.

[0045] The embodiment of FIG. 6 also includes a second carbon getter (13).

[0046] The second carbon getter (13) may have the same shape as the first carbon getter (11) or a different shape. It is preferable that the second carbon getter (13) be placed on a shelf on the inner surface of the second inner container (4). For example, since the wall of the bottom portion (4b) may be thicker than the wall of the top portion (4a), when mounted, the inner edge of the bottom portion (4b) may be further extended in the direction of the central axis of the second inner container (4) to form a shelf. The second carbon getter (13) is formed of a material having a melting point of 2200°C or higher and reacting with carbon species evaporated from the source material to form a carbide layer. Such materials may be tantalum, niobium, and tungsten, but are not limited thereto. In another embodiment, the second carbon getter (13) comprises a plurality of parts. The plurality of parts may be formed of the same or different materials. The arrangement of the first source material (1a) and the first substrate (1b) inside the first inner container (3) and the arrangement of the second source material (2a) and the second substrate (2b) inside the second inner container (4) provide essentially the same growth characteristics for the two single crystal layers grown on the respective first and second substrates (1b, 2b).

[0047] FIG. 7 illustrates an insulating container (6). The insulating container is preferably cylindrical and formed of high-density graphite, and also includes an upper portion (6a), a middle portion (6b), and a bottom portion (6c). The upper portion (6a) and the bottom portion (6c) have a fiber direction perpendicular to the central axis of the cylindrical insulating container (6). The middle portion (6b) has a fiber direction parallel to the central axis. The preferred fiber direction is indicated by an arrow in FIG. 7. By having these fiber directions, heat dissipation is improved, and consequently, the temperature uniformity inside the insulating container (6) is improved. The upper portion (6a) further includes a measuring hole (6d). The hole (6d) must be suitable and sufficiently large to accommodate measuring equipment, such as a temperature measuring device. The measuring hole (6d) must also be configured to maintain sufficient pressure within the insulating container (6). In another embodiment, the measuring hole is instead located in the bottom portion (6c). In another embodiment, the upper portion (6a) and the bottom portion (6c) each include a measuring hole. In another embodiment, the insulating container (6) does not include a measuring hole (6d). In this embodiment, the internal temperature of the insulating container is calculated from the known energy input into the system. The insulating container (6) is placed within the outer container (7) on an insulating container support (not shown) located at the bottom of the outer container (7). The insulating container (6) is preferably a quartz (SiO2) tube.

[0048] Now, the present method will be described with reference to the system design described above, but those skilled in the art will know that this design is merely an example and that other designs may be used as long as desired growth conditions are achieved. The present method comprises the step of placing a first source material (1a) and a first substrate (1b) in a first inner container and placing a second source material (2a) and a second substrate (2b) in a second inner container by setting up a system (100) according to the embodiment described above, and the first and second SiC single crystal layers can be grown on the respective first and second substrates (1b, 2b).

[0049] FIG. 8 illustrates the process flow of the present method. The first step is an evacuation step (S101) comprising emptying the system (100) using a pump placed outside the outer container (7). Specifically, the pressure inside the first and second inner containers (3, 4) is preferably 10 4 It must be less than mbar. In the introduction step (S101), the system (100) is preheated. The second step is a flushing step (S102) in which the system (100) is flushed with an inert gas, preferably argon (Ar) gas. After the flushing step (S102), the pressure of the system (100) must not exceed preferably 5 mbar, more preferably 1 mbar. The third step is a heating step (S103) in which the system (100) is heated to the growth temperature of the single crystal layer. An exemplary growth temperature is 1900-2000°C. During the heating step, the temperature is increased at a rate that provides the desired initial sublimation of the first and second source materials and promotes the formation of crystal nucleations on the substrate. This temperature increase is preferably 10-50°C / m2, and more preferably 20-30°C / m2. The fourth step is a growth step (S104) in which the temperature within the system is maintained at a constant growth temperature and two single crystal layers are grown on the first and second substrates, respectively. The temperature is maintained at this temperature until the thickness of the single crystal layer reaches a desired thickness, preferably at least 50 μm. The fifth step is a cooling step (S105) in which the system (100) and the single crystal layer are cooled to room temperature.

[0050] Although the present invention has been described in detail in relation to the embodiments discussed, various modifications may be made by those skilled in the art within the scope of the appended claims without departing from the inventive spirit of the present disclosure. For example, the system disclosed herein may be suitable for producing a single-crystal layer from materials other than SiC, such as aluminum nitride (AIN). In such cases, it is naturally necessary to use a different source material, and those skilled in the art know that a source material having essentially the same properties as the source material disclosed herein is used. Furthermore, the present method may be used to produce one or more layers in the same cavity, as can be easily realized by those skilled in the art.

[0051] All alternative embodiments or parts of the embodiments described above may be freely combined without departing from the spirit of the invention, as long as the combination is not contradictory.

Claims

Claim 1 A system (100) for simultaneously generating a first epitaxial single crystal layer and a second epitaxial single crystal layer on each of a first substrate and a second substrate, comprising: a first inner container (3) having a first cavity defined for accommodating a first monolithic silicon carbide source material and a first substrate, wherein the first monolithic silicon carbide source material is disposed below the first substrate; a second inner container (4) having a second cavity defined for accommodating a second monolithic silicon carbide source material and a second substrate, wherein the second monolithic silicon carbide source material is disposed above the second substrate; an insulating container (6) disposed to accommodate the first inner container (3) and the second inner container (4) inside; and an outer container (7) disposed to accommodate the insulating container (6), the first inner container (3), and the second inner container (4) inside. A system (100) comprising a heating means (8) disposed outside the outer container (7) and configured to simultaneously heat the first cavity and the second cavity, wherein the first inner container (3) is disposed on the second inner container (4). Claim 2 A system (100) according to claim 1, further comprising a heating element (5) disposed between the first inner container (3) and the second inner container (4) inside the insulating container (6), and the heating means (8) further configured to simultaneously heat the heating element (5), the first cavity, and the second cavity. Claim 3 In paragraph 2, the first inner container (3), the second inner container (4), and the heating element (5) are formed integrally, in a system (100). Claim 4 A system (100) wherein, in any one of claims 1 to 3, the first inner container (3) and the second inner container (4) are cylindrical in shape and have the same diameter. Claim 5 A system (100) wherein, in any one of claims 1 to 3, the first inner container (3) comprises an upper portion and a bottom portion, and the second inner container (4) comprises an upper portion and a bottom portion, and the bottom portion of the first inner container (3) is essentially the same as the upper portion of the second inner container (4). Claim 6 A system (100) further comprising, in any one of claims 1 to 3, a first means (10a, 10b) for disposing of the first monolithic silicon carbide source material at a predetermined distance from the first substrate within the first cavity; and a second means (12a, 12b) for disposing of the second monolithic silicon carbide source material at a predetermined distance from the second substrate within the second cavity. Claim 7 A system (100) according to any one of claims 1 to 3, wherein the insulating container (6) and the outer container (7) are cylindrical in shape, and the first monolithic silicon carbide source material and the second monolithic silicon carbide source material and the first substrate and the second substrate are disk-shaped. Claim 8 A system (100) further comprising, in any one of claims 1 to 3, a first carbon getter disposed inside the first inner container (3) and a second carbon getter disposed inside the second inner container (4). Claim 9 In any one of claims 1 to 3, the heating means (8) is movable along the outer container (7), the system (100). Claim 10 A method for simultaneously forming a first epitaxial single crystal layer and a second epitaxial single crystal layer on each of a first substrate and a second substrate, comprising: providing a first inner container (3) defining a first cavity for accommodating a first monolithic silicon carbide source material and a first substrate; providing a second inner container (4) defining a second cavity for accommodating a second monolithic silicon carbide source material and a second substrate; disposing of the first monolithic silicon carbide source material below the first substrate in the first cavity and disposing of the second monolithic silicon carbide source material above the second substrate in the second cavity; disposing of the first inner container (3) and the second inner container (4) within an insulating container (6), wherein the first inner container (3) is disposed above the second inner container (4); disposing of the insulating container (6) within an outer container (7), and the first cavity and the second A method comprising: providing a heating means (8) outside the outer container (7) to simultaneously heat the cavities; emptying the first cavity and the second cavity to a predetermined pressure; introducing an inert gas into the first cavity and the second cavity; simultaneously raising the temperature of the first cavity and the second cavity to a predetermined growth temperature by the heating means (8); maintaining the predetermined growth temperature in the first cavity and the second cavity until a predetermined thickness of the first epitaxial single crystal layer and the second epitaxial single crystal layer on each of the first substrate and the second substrate is achieved; and cooling the first substrate and the second substrate. Claim 11 A method according to claim 10, further comprising providing a heating element (5) between the first inner container (3) and the second inner container (4). Claim 12 A method according to claim 11, wherein raising the temperature of the first cavity and the second cavity further includes raising the temperature of the heating element (5) simultaneously. Claim 13 delete Claim 14 delete Claim 15 delete Claim 16 delete Claim 17 delete

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