A device comprising a thick (AlzGa1-z)2O3 layer on a (001)Ga2O3 substrate using an (AlxGa1-x)2O3 buffer layer, and a method for manufacturing and using the same.

Abstract

This specification includes (Al x Ga 1-x (001) A thick (Al) buffer layer is used on a Ga2O3 substrate. z Ga 1-z Devices comprising a 2O3 (e.g., Ga2O3) layer and methods for manufacturing and using the same are disclosed. For example, this specification discloses (001) a Ga2O3 substrate and (Al x Ga 1-x A first layer containing )2O3 (where x is 0 to 0.5), and (Al z Ga 1-z A device is disclosed comprising a first layer and a second layer comprising 2O3 (where z is 0 to 0.2) (e.g., Ga2O3), wherein the first layer is disposed on a substrate and the second layer is disposed on the first layer, so that the first layer is sandwiched between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 1000 μm (e.g., 5 μm to 15 μm). The Specified also discloses a method for manufacturing any of the devices disclosed herein, for example, using metal-organic chemical vapor deposition (MOCVD).

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims priority under U.S. Provisional Patent Application No. 63 / 463,931, filed 4 May 2023, which is incorporated herein by reference in its entirety.

[0002] Description of government aid This invention was made with government assistance under license / contract number FA9950-18-1-0479 granted by the U.S. Air Force Chemical Research Office. The U.S. Government reserves certain rights in this invention. [Background technology]

[0003] β-Ga2O3 is considered a promising semiconductor material for next-generation high-power electronic devices due to its outstanding properties, including a large energy bandgap (4.8 eV), controllable n-type doping, and high predicted breakdown field strength (8 MV / cm). Further development of high-power electronic devices with even higher reverse breakdown voltages requires a thick drift layer with a smooth surface morphology and controllable low doping. Therefore, particularly on (001)-oriented β-Ga2O3 substrates, growth of high-quality, thick β-Ga2O3 at relatively fast growth rates is necessary. The compositions, methods, and devices discussed herein address these and other needs. [Overview of the project]

[0004] According to the purpose of the compositions, methods and devices disclosed herein, which are embodied and described in general terms, the subject matter disclosed is (Al x Ga 1-x (001) A thick (Al) layer is used on a Ga2O3 substrate. z Ga 1-z This invention relates to a device containing a 2O3 (e.g., Ga2O3) layer, and to methods for manufacturing and using the same.

[0005] For example, this specification includes (Al x Ga 1-x)A method for depositing a thick β-Ga2O3 film on a (001) Ga2O3 substrate using a 2O3 buffer layer is disclosed.

[0006] For example, this specification discloses a device including a (001) Ga2O3 substrate. The device further includes a first layer containing (Al x Ga 1-x )2O3 where x ranges from 0 to 0.5. The device further includes a second layer containing (Al z Ga 1-z )2O3 where z ranges from 0 to 0.2. The first layer is disposed on the substrate, and the second layer is disposed on the first layer, such that the first layer is sandwiched between the substrate and the second layer. In some embodiments, the second layer has an average thickness of 5 μm to 1000 μm.

[0007] In some embodiments, the substrate includes a (001) β-Ga2O3 substrate.

[0008] In some embodiments, the first layer contains (Al x Ga 1-x )2O3 where x ranges from 0 to 0.3.

[0009] In some embodiments, the first layer has an average thickness of 5 to 1000 nm, 5 nm to 500 nm, 10 nm to 100 nm, or 15 to 25 nm.

[0010] In some embodiments, the second layer contains Ga2O3. In some embodiments, the second layer contains β-Ga2O3.

[0011] In some embodiments, the second layer has an average thickness of 5 μm to 100 μm. In some embodiments, the second layer has an average thickness of 5 μm to 15 μm. In some embodiments, the second layer has an average thickness of 6 μm to 9 μm.

[0012] In some embodiments, the device includes a (001) Ga2O3 substrate and (Al x Ga 1-xThe material comprises a first layer containing 2O3 (where x is 0 to 0.5) and a second layer containing Ga2O3, wherein the first layer is placed on a substrate and the second layer is placed on top of the first layer, so that the first layer is sandwiched between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 15 μm.

[0013] In some embodiments, the second layer has a lower surface roughness than the same device in the absence of the first layer.

[0014] In some embodiments, the second layer is relatively smooth and / or substantially free of cracks.

[0015] In some embodiments, the device includes optical devices, electronic devices, optoelectronic devices, or combinations thereof.

[0016] In some embodiments, the device includes a horizontal device, a vertical device, or a combination thereof.

[0017] Furthermore, this specification also discloses methods for manufacturing any of the devices described herein. For example, the method may include depositing a first layer on a substrate and depositing a second layer on the first layer.

[0018] In some embodiments, the first and / or second layers are deposited using metal-organic chemical vapor deposition (MOCVD).

[0019] In some embodiments, the first layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof. In some embodiments, the aluminum concentration in the first layer can be controlled by controlling the concentration and / or ratio of the precursors, temperature, pressure, or a combination thereof.

[0020] In some embodiments, this method generates a first layer at a growth rate of 100-2000 nm / hour. In some embodiments, this method generates a first layer at a growth rate of 100-800 nm / hour, for example, 400 nm / hour.

[0021] In some embodiments, the second layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof. In some embodiments, the second layer is deposited using MOCVD with a Ga-containing precursor and an oxygen-containing precursor.

[0022] In some embodiments, this method generates a second layer at a growth rate of 1 to 20 μm / hour. In some embodiments, this method generates a second layer at a growth rate of 1 to 10 μm / hour, for example, 3 μm / hour.

[0023] In some embodiments, the Al-containing precursor, the Ga-containing precursor, and / or the oxygen-containing precursor independently contain a fluid such as a gas.

[0024] In some embodiments, the Al-containing precursor includes trimethylaluminum (TMAl), triethylaluminum (TEAl), or a combination thereof. In some embodiments, the Al-containing precursor includes trimethylaluminum (TMAl).

[0025] In some embodiments, the Ga-containing precursor includes trimethylgallium (TMGa), triethylgallium (TEGa), or a combination thereof.

[0026] In some embodiments, the oxygen-containing precursor contains O2.

[0027] In some embodiments, the method further comprises introducing an additional precursor containing a dopant, thereby the first layer and / or second layer further containing the dopant. In some embodiments, the additional precursor is provided as a fluid such as a gas. In some embodiments, the additional precursor contains an n-type dopant such as a silicon-containing precursor.

[0028] In some embodiments, a carrier gas is supplied independently to an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, an additional precursor (if any), or a combination thereof. In some embodiments, the carrier gas includes argon, helium, N2, or a combination thereof.

[0029] In some embodiments, the method is carried out at a temperature of 650 to 1100°C and / or a pressure of 5 to 600 Torrell. In some embodiments, the method is carried out at a temperature of 650 to 1000°C and / or a pressure of 5 to 600 Torrell.

[0030] Further advantages of the disclosed compositions, devices, and methods will be partially described below and partially apparent from the specification. The advantages of the disclosed compositions, devices, and methods are realized and achieved by the elements and combinations specifically pointed out in the appended claims. It should be understood that both the above summary and the following detailed description are merely illustrative and explanatory and do not limit the claimed disclosed devices and methods.

[0031] Details of one or more embodiments of the present invention are described in the accompanying drawings and the following description. Other characteristics, purposes, and advantages of the present invention will become apparent from the description and drawings, as well as from the claims.

[0032] The accompanying drawings, which are incorporated herein by reference and constitute part of this specification, illustrate several aspects of this disclosure and, together with the description, serve to illustrate the principles of this disclosure. [Brief explanation of the drawing]

[0033] [Figure 1A] (001) Surface SEM image of a β-Ga2O3 film (9 μm) grown with TMGa on a Sn-doped β-Ga2O3 substrate: Wide field of view of the cracking region. The film was grown at a growth rate of 3 μm / hour without using an AlGaO buffer layer. [Figure 1B] (001) Surface SEM image of a β-Ga2O3 film (9 μm) grown with TMGa on a Sn-doped β-Ga2O3 substrate: Wide field of view of the non-cracking region. The film was grown at a growth rate of 3 μm / hour without using an AlGaO buffer layer. [Figure 1C] (001) Surface SEM image of a β-Ga2O3 film (9 μm) grown with TMGa on a Sn-doped β-Ga2O3 substrate: High magnification of the cracking region. The film was grown at a growth rate of 3 μm / hour without using an AlGaO buffer layer. [Figure 1D] (001) Surface SEM image of a β-Ga2O3 film (9 μm) grown with TMGa on a Sn-doped β-Ga2O3 substrate: High magnification of the non-cracking region. The film was grown at a growth rate of 3 μm / hour without using an AlGaO buffer layer. [Figure 2] This is a schematic diagram of a relatively thick β-Ga2O3 film grown on a (001) oriented β-Ga2O3 substrate, using a thin β-(AlxGa1-x)2O3 buffer layer as a buffer to suppress cracking of the topmost Ga2O3 layer. [Figure 3] This is a schematic diagram of a β-Ga2O3 film grown on a (001) oriented β-Ga2O3 substrate, using a 20 nm thin β-(AlxGa1-x)2O3 buffer layer with a different Al composition between the β-Ga2O3 epitaxial layer and the substrate. [Figure 4A] This is an optical macroscopic surface image of a β-Ga2O3 film (6 μm) grown with TMGa on a (001)β-Ga2O3 substrate equipped with a thin β-(AlxGa1-x)2O3 buffer layer (x=0%). [Figure 4B] This is an optical macroscopic surface image of a β-Ga2O3 film (6 μm) grown with TMGa on a (001)β-Ga2O3 substrate equipped with a thin β-(AlxGa1-x)2O3 buffer layer (x=8%). [Figure 4C] This is an optical macroscopic surface image of a β-Ga2O3 film (6 μm) grown with TMGa on a (001)β-Ga2O3 substrate equipped with a thin β-(AlxGa1-x)2O3 buffer layer (x=15%). [Figure 4D] This is an optical macroscopic surface image of a β-Ga2O3 film (6 μm) grown with TMGa on a (001)β-Ga2O3 substrate having a thin β-(AlxGa1-x)2O3 buffer layer (x=22%). [Figure 4E] This is an optical macroscopic surface image of a β-Ga2O3 film (6 μm) grown with TMGa on a (001)β-Ga2O3 substrate having a thin β-(AlxGa1-x)2O3 buffer layer (x=29%). [Figure 5A] This is an optical macroscopic surface image of a β-Ga2O3 film (9 μm) grown with TMGa on a (001)β-Ga2O3 substrate equipped with a thin β-(AlxGa1-x)2O3 buffer layer (x=0%). [Figure 5B] This is an optical macroscopic surface image of a β-Ga2O3 film (9 μm) grown with TMGa on a (001)β-Ga2O3 substrate equipped with a thin β-(AlxGa1-x)2O3 buffer layer (x=29%). [Figure 6] This is a schematic diagram of a β-Ga2O3 film approximately 6 μm thick grown on a (001) oriented β-Ga2O3 substrate using a thin (AlxGa1-x)2O3 buffer layer. [Figure 7] This is an optical macroscopic surface image of a Ga2O3 film (approximately 6 μm thick) grown with TMGa on a (001)β-Ga2O3 substrate equipped with an (AlxGa1-x)2O3 buffer layer. [Figure 8] This is an optical macroscopic surface image of a Ga2O3 film (approximately 6 μm thick) grown with TMGa on a (001)β-Ga2O3 substrate equipped with an (AlxGa1-x)2O3 buffer layer. Two cracks were observed, indicated by arrows. [Figure 9] This is an SEM image of the surface of a Ga2O3 film (approximately 6 μm thick) grown with TMGa on a (001)β-Ga2O3 substrate equipped with an (AlxGa1-x)2O3 buffer layer. [Figure 10]This is an SEM image of the surface of a Ga2O3 film (approximately 6 μm thick) grown with TMGa on a (001)β-Ga2O3 substrate equipped with an (AlxGa1-x)2O3 buffer layer. [Figure 11] This is an AFM of the surface of a Ga2O3 film (approximately 6 μm thick) grown with TMGa on a (001)β-Ga2O3 substrate equipped with an (AlxGa1-x)2O3 buffer layer. [Modes for carrying out the invention]

[0034] The compositions, methods, and devices described herein may be more readily understood by referring to the following detailed descriptions of specific aspects of the disclosed subject matter and the examples contained herein.

[0035] Before disclosing and describing the compositions, methods, and devices of the present invention, it should be understood that the embodiments described below are not limited to specific synthesis methods or specific reagents, and therefore may vary considerably. It should also be understood that the terms used herein are intended solely to describe specific embodiments and are not intended to limit them.

[0036] Furthermore, various publications are referenced throughout this specification. The disclosures of those publications as a whole are incorporated herein by reference to more completely explain the current art to which the subject matter of this disclosure pertains. The disclosed references are also incorporated herein by reference individually and specifically with respect to the material contained therein, as considered in the sentences on which the references are based.

[0037] In this specification and the subsequent claims, several terms are referenced and defined as follows:

[0038] Throughout this description and the claims, the word “comprise” and other forms thereof, such as “comprising” and “comprises,” mean “including but not limited to,” and are not intended to exclude, for example, other appendages, components, integers, or steps.

[0039] As used herein and in the appended claims, the singular forms "a," "an," and "the" include multiple references unless the context clearly indicates otherwise. Thus, for example, a reference to "composition" includes mixtures of two or more such compositions; a reference to "agent" includes mixtures of two or more such agents; a reference to "component" includes mixtures of two or more such components, and so on.

[0040] "Optional" or "optional" means that the event or situation described thereafter may or may not occur, and that the description includes both instances in which the event or situation occurs and instances in which it does not occur.

[0041] A range may be expressed herein as "approximately" from one particular value and / or "approximately" to another particular value. "Approximately" means within 5% of a value, for example, within 4, 3, 2, or 1% of the value. Where such a range is expressed, another aspect includes from one particular value and / or to another particular value. Similarly, where a value is expressed as an approximation using the preceding "approximately," it will be understood that the particular value forms another aspect. It will be further understood that each endpoint of a range is significant in relation to and independently of the other endpoints.

[0042] In this specification, values ​​may be expressed as "mean" values. "Mean" generally refers to the statistical mean.

[0043] "Effectively" means within 5%, for example, within 4%, 3%, 2%, or 1%.

[0044] "Exemplary" means "an example of ~" and is not intended to indicate a preferred or ideal embodiment. "Such as" is used for explanatory purposes, not in a restrictive sense.

[0045] Throughout this specification, it should be understood that the identifiers “First” and “Second” are used simply to facilitate the distinction between the various components and steps of the disclosed subject matter. The identifiers “First” and “Second” are not intended to indicate any particular order, quantity, priority, or importance of the components or steps to which these terms are applied.

[0046] In this specification and the concluding claims, any reference to parts by weight of a particular element or component in a composition indicates a weight relationship between the element or component in the composition or article in which the parts by weight are expressed and any other element or component. Thus, in a compound containing 2 parts by weight of component X and 5 parts by weight of component Y, X and Y are present in a weight ratio of 2:5, and in such a ratio whether or not further components are present in the compound.

[0047] The weight percentage (W%) of a component is based on the total weight of the preparation or composition containing that component, unless otherwise specified.

[0048] As used herein, the term “or any combination thereof” refers to all permutations and combinations of the listed items preceding that term. For example, “A, B, C, or any combination thereof” is intended to include A, B, C, AB, AC, BC, or ABC, and, where the order is important in a particular context, at least one of BA, CA, CB, CBA, BCA, ACB, BAC, or CAB. Continuing with this embodiment, combinations containing repetitions of one or more items or terms, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, etc. A person skilled in the art will typically understand that there is no limit to the number of items or terms in any combination, unless otherwise evident from the context.

[0049] Device, manufacturing method thereof, and method of use thereof This specification includes (Al x Ga 1-x (001) A thick (Al) buffer layer is used on a Ga2O3 substrate. z Ga 1-z A device comprising a 2O3 layer and a method for manufacturing and using the same are disclosed. For example, this specification discloses (Al x Ga 1-x A device comprising a thick Ga2O3 layer on a Ga2O3 substrate using a 2O3 buffer layer (001) is disclosed, as well as a method for manufacturing and using the same.

[0050] For example, this specification discloses a device including a (001)Ga2O3 substrate.

[0051] In some embodiments, the substrate contains (001)β-Ga2O3.

[0052] The device further includes a first layer disposed on the substrate. The first layer is (Al x Ga 1-x)2O3 (where x is between 0 and 0.5). For example, x is 0 or greater (e.g., 0.01 or greater, 0.02 or greater, 0.03 or greater, 0.04 or greater, 0.05 or greater, 0.06 or greater, 0.07 or greater, 0.08 or greater, 0.09 or greater, 0.10 or greater, 0.11 or greater, 0.12 or greater, 0.13 or greater, 0.14 or greater, 0.15 or greater, 0.16 or greater, 0.17 or greater, 0.18 or greater, 0.19 or greater, 0.20 or greater, 0.21 or greater, 0.22 or greater, 0.23 or greater, 0.24 or greater) (0.25 or higher, 0.26 or higher, 0.27 or higher, 0.28 or higher, 0.29 or higher, 0.30 or higher, 0.31 or higher, 0.32 or higher, 0.33 or higher, 0.34 or higher, 0.35 or higher, 0.36 or higher, 0.37 or higher, 0.38 or higher, 0.39 or higher, 0.40 or higher, 0.41 or higher, 0.42 or higher, 0.43 or higher, 0.44 or higher, 0.45 or higher, 0.46 or higher, 0.47 or higher, 0.48 or higher, or 0.49 or higher). In several trials, x was found to be less than or equal to 0.5 (for example, less than or equal to 0.49, less than or equal to 0.48, less than or equal to 0.47, less than or equal to 0.46, less than or equal to 0.45, less than or equal to 0.44, less than or equal to 0.43, less than or equal to 0.42, less than or equal to 0.41, less than or equal to 0.40, less than or equal to 0.39, less than or equal to 0.38, less than or equal to 0.37, less than or equal to 0.36, less than or equal to 0.35, less than or equal to 0.34, less than or equal to 0.33, less than or equal to 0.32, less than or equal to 0.31, less than or equal to 0.30, less than or equal to 0.29, less than or equal to 0.28, less than or equal to 0.27, 0. (26 or less, 0.25 or less, 0.24 or less, 0.23 or less, 0.22 or less, 0.21 or less, 0.20 or less, 0.19 or less, 0.18 or less, 0.17 or less, 0.16 or less, 0.15 or less, 0.14 or less, 0.13 or less, 0.12 or less, 0.11 or less, 0.10 or less, 0.09 or less, 0.08 or less, 0.07 or less, 0.06 or less, 0.05 or less, 0.04 or less, 0.03 or less, 0.02 or less, or 0.01 or less). The value of x can be within the range of any of the minimum and maximum values ​​above. For example, x can be 0 to 0.5 (e.g., 0 to 0.25, 0.25 to 0.5, 0 to 0.1, 0.1 to 0.2, 0.2 to 0.3, 0.3 to 0.4, 0.4 to 0.5, 0 to 0.4, 0 to 0.3, 0 to 0.2, 0.1 to 0.5, 0.2 to 0.5, 0.3 to 0.5, or 0.1 to 0.4). In some embodiments, the first layer is (Al x Ga 1-x ) contains 2O3 (where x is between 0 and 0.3).

[0053] The first layer may have an average thickness of 5 nanometers (nm) or more (for example, 10 nm or more, 15 nm or more, 20 nm or more, 25 nm or more, 30 nm or more, 35 nm or more, 40 nm or more, 45 nm or more, 50 nm or more, 60 nm or more, 70 nm or more, 80 nm or more, 90 nm or more, 100 nm or more, 125 nm or more, 150 nm or more, 175 nm or more, 200 nm or more, 225 nm or more, 250 nm or more, 300 nm or more, 350 nm or more, 400 nm or more, 450 nm or more, 500 nm or more, 550 nm or more, 600 nm or more, 650 nm or more, 700 nm or more, 750 nm or more, 800 nm or more, 850 nm or more, or 900 nm or more). In some embodiments, the first layer may have an average thickness of 1000 nm or less (e.g., 950 nm or less, 900 nm or less, 850 nm or less, 800 nm or less, 750 nm or less, 700 nm or less, 650 nm or less, 600 nm or less, 550 nm or less, 500 nm or less, 450 nm or less, 400 nm or less, 350 nm or less, 300 nm or less, 250 nm or less, 225 nm or less, 200 nm or less, 175 nm or less, 150 nm or less, 125 nm or less, 100 nm or less, 90 nm or less, 80 nm or less, 70 nm or less, 60 nm or less, 50 nm or less, 45 nm or less, 40 nm or less, 35 nm or less, 30 nm or less, 25 nm or less, 20 nm or less, 15 nm or less, or 10 nm or less). The average thickness of the first layer may be in the range from any of the above minimum values ​​to any of the above maximum values.For example, the first layer is 5nm~1000nm (e.g., 5~500nm, 500nm~1000nm, 5~250nm, 250~500nm, 500nm~750nm, 750nm~1000nm, 5nm~100nm, 100nm~200nm, 200nm~300nm, 300nm~400nm, 400nm~500nm, 500~600nm, 600~700nm, 700~800nm, 800~900nm, 900~1000nm, 5nm~900nm, 5~800nm, 5~700nm, 5~600nm, 5nm~400nm, 5nm~300nm, 5nm~200nm, It can have an average thickness of 5nm~100nm, 5nm~50nm, 5nm~25nm, 10~1000nm, 25~1000nm, 50~1000nm, 100~1000nm, 200~1000nm, 300~1000nm, 400~1000nm, 600~1000nm, 700~1000nm, 800~1000nm, 10~900nm, 25~800nm, 10nm~500nm, 25nm~500nm, 50~500nm, 100~500nm, 200~500nm, 300~500nm, 10nm~450nm, 10nm~100nm, or 15~25nm).

[0054] In some embodiments, the first layer is (Al x Ga 1-x )2O3 (where x is 0 to 0.5) has an average thickness of 5 to 500 nm. In some examples, the first layer is (Al x Ga 1-x )2O3 (where x is 0 to 0.5) has an average thickness of 10 to 100 nm. In some examples, the first layer is (Al x Ga 1-x It contains 2O3 (where x is 0 to 0.5) and has an average thickness of 15 to 25 nm.

[0055] In some embodiments, the first layer is (Al x Ga 1-x )2O3 (where x is 0 to 0.3) has an average thickness of 5 to 500 nm. In some examples, the first layer is (Al x Ga 1-x)2O3 (where x is 0 to 0.3) has an average thickness of 10 to 100 nm. In some examples, the first layer is (Al x Ga 1-x It contains 2O3 (where x is 0 to 0.3) and has an average thickness of 15 to 25 nm.

[0056] The device further includes a second layer, the second layer being placed on top of the first layer, thereby sandwiching the first layer between the substrate and the second layer.

[0057] In some embodiments, the second layer is (Al x Ga 1-z )2O3 (where z is between 0 and 0.2). For example, z is 0 or greater (e.g., 0.01 or greater, 0.02 or greater, 0.03 or greater, 0.04 or greater, 0.05 or greater, 0.06 or greater, 0.07 or greater, 0.08 or greater, 0.09 or greater, 0.10 or greater, 0.11 or greater, 0.12 or greater, 0.13 or greater, 0.14 or greater, 0.15 or greater, 0.16 or greater, 0.17 or greater, 0.18 or greater, 0.19 or greater). In some embodiments, z is less than or equal to 0.2 (e.g., less than or equal to 0.19, less than or equal to 0.18, less than or equal to 0.17, less than or equal to 0.16, less than or equal to 0.15, less than or equal to 0.14, less than or equal to 0.13, less than or equal to 0.12, less than or equal to 0.11, less than or equal to 0.10, less than or equal to 0.09, less than or equal to 0.08, less than or equal to 0.07, less than or equal to 0.06, less than or equal to 0.05, less than or equal to 0.04, less than or equal to 0.03, less than or equal to 0.02, or less than or equal to 0.01). The value of z can be in the range from any of the minimum values ​​above to any of the maximum values ​​above. For example, z can be 0 to 0.2 (e.g., 0 to 0.1, 0.1 to 0.2, 0 to 0.05, 0.05 to 0.1, 0.1 to 0.15, 0.15 to 0.2, 0 to 0.15, 0.05 to 0.2, or 0.05 to 0.15). In some embodiments, x is 0, and the second layer contains Ga2O3. In some embodiments, the second layer contains β-Ga2O3.

[0058] The second layer is, for example, 5 micrometers (microns, μm) or larger (for example, 5.5 μm or larger, 6 μm or larger, 6.5 μm or larger, 7 μm or larger, 7.5 μm or larger, 8 μm or larger, 8.5 μm or larger, 9 μm or larger, 9.5 μm or larger, 10 μm or larger, 10.5 μm or larger, 11 μm or larger, 11.5 μm or larger, 12 μm or larger, 12.5 μm or larger, 13 μm or larger, 13.5 μm or larger, 14 μm or larger, 14.5 μm or larger, 15 μm or larger, 16 μm or larger, 17 μm or larger, 18 μm or larger, 19 μm or larger, 20 μm or larger). The average thickness can be 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, 45 μm or more, 50 μm or more, 60 μm or more, 70 μm or more, 80 μm or more, 90 μm or more, 100 μm or more, 125 μm or more, 150 μm or more, 175 μm or more, 200 μm or more, 225 μm or more, 250 μm or more, 300 μm or more, 350 μm or more, 400 μm or more, 450 μm or more, 500 μm or more, 600 μm or more, 700 μm or more, 800 μm or more, or 900 μm or more. In some examples, the second layer is 1000 μm or less (for example, 900 μm or less, 800 μm or less, 700 μm or less, 600 μm or less, 500 μm or less, 450 μm or less, 400 μm or less, 350 μm or less, 300 μm or less, 250 μm or less, 225 μm or less, 200 μm or less, 175 μm or less, 150 μm or less, 125 μm or less, 100 μm or less, 90 μm or less, 80 μm or less, 70 μm or less, 60 μm or less, 50 μm or less, 45 μm or less, 40 μm or less, 35 μm or less). The average thickness of the second layer may be 30 μm or less, 25 μm or less, 20 μm or less, 19 μm or less, 18 μm or less, 17 μm or less, 16 μm or less, 15 μm or less, 14.5 μm or less, 14 μm or less, 13.5 μm or less, 13 μm or less, 12.5 μm or less, 12 μm or less, 11.5 μm or less, 11 μm or less, 10.5 μm or less, 10 μm or less, 9.5 μm or less, 9 μm or less, 8.5 μm or less, 8 μm or less, 7.5 μm or less, 7 μm or less, 6.5 μm or less, or 6 μm or less. The average thickness of the second layer may be in the range from any of the above minimum values ​​to any of the above maximum values.For example, the second layer is 5-1000 μm (e.g., 5-500 μm, 500-1000 μm, 5-200 μm, 200-400 μm, 400-600 μm, 600-800 μm, 800-1000 μm, 5-800 μm, 5-600 μm, 5-400 μm, 5-100 μm, 5-50 μm, 5-25 μm, 5 The average thickness can be ~15 μm, 10~1000 μm, 15~1000 μm, 25~1000 μm, 50~1000 μm, 100~1000 μm, 200~1000 μm, 400~1000 μm, 600~1000 μm, 10~1900 μm, 15~1800 μm, or 25~1500 μm. In some examples, the second layer can have an average thickness of 5~100 μm. The second layer may have an average thickness of 5 μm to 15 μm (for example, 5 to 10 μm, 10 to 15 μm, 5 to 7.5 μm, 7.5 to 10 μm, 10 to 12.5 μm, 12.5 to 15 μm, 5 to 14 μm, 5 to 13 μm, 5 to 12 μm, 5 to 11 μm, 5 to 9 μm, 5 to 8 μm, 5 to 7 μm, 6 to 15 μm, 7 to 15 μm, 8 to 15 μm, 9 to 15 μm, 11 to 15 μm, 12 to 15 μm, 13 to 15 μm, 5.5 to 14.5 μm, or 6 to 9 μm).

[0059] For example, this specification includes (001) a Ga2O3 substrate and (Al x Ga 1-x A first layer containing )2O3 (where x is 0 to 0.5), and (Al z Ga 1-z A device is disclosed comprising a first layer and a second layer comprising 2O3 (where z is 0 to 0.2), wherein the first layer is disposed on a substrate and the second layer is disposed on the first layer, thereby sandwiching the first layer between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 1000 μm.

[0060] For example, this specification includes (001) a Ga2O3 substrate and (Al x Ga 1-xA device is disclosed comprising a first layer containing 2O3 (where x is 0 to 0.5) and a second layer containing Ga2O3, wherein the first layer is disposed on a substrate and the second layer is disposed on the first layer, so that the first layer is sandwiched between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 15 μm.

[0061] In some embodiments, the first layer is (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.5), the first layer has an average thickness of 5 to 500 nm, and the second layer has an average thickness of 5 to 15 μm. In some examples, the first layer is made of (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.5), and the second layer has an average thickness of 10 to 100 nm, and the second layer has an average thickness of 5 to 15 μm. In some examples, the first layer is made of (Al x Ga 1-x The material contains 2O3 (where x is 0 to 0.5), the first layer has an average thickness of 15 to 25 nm, and the second layer has an average thickness of 5 to 15 μm.

[0062] In some embodiments, the first layer is (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.5), the first layer has an average thickness of 5 to 500 nm, and the second layer has an average thickness of 6 to 9 μm. In some examples, the first layer is made of (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.5), and the second layer has an average thickness of 10 to 100 nm, and the second layer has an average thickness of 6 to 9 μm. In some examples, the first layer is made of (Al x Ga 1-x The material contains 2O3 (where x is 0 to 0.5), the first layer has an average thickness of 15 to 25 nm, and the second layer has an average thickness of 6 to 9 μm.

[0063] In some embodiments, the first layer is (Al x Ga 1-xThe first layer contains 2O3 (where x is 0 to 0.3), the first layer has an average thickness of 5 to 500 nm, and the second layer has an average thickness of 5 to 15 μm. In some examples, the first layer is made of (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.3), and the second layer has an average thickness of 10 to 100 nm, and the second layer has an average thickness of 5 to 15 μm. In some examples, the first layer is made of (Al x Ga 1-x The material contains 2O3 (where x is 0 to 0.3), the first layer has an average thickness of 15 to 25 nm, and the second layer has an average thickness of 5 to 15 μm.

[0064] In some embodiments, the first layer is (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.3), the first layer has an average thickness of 5 to 500 nm, and the second layer has an average thickness of 6 to 9 μm. In some examples, the first layer is made of (Al x Ga 1-x The first layer contains 2O3 (where x is 0 to 0.3), and the second layer has an average thickness of 10 to 100 nm, and the second layer has an average thickness of 6 to 9 μm. In some examples, the first layer is made of (Al x Ga 1-x The material contains 2O3 (where x is 0 to 0.3), the first layer has an average thickness of 15 to 25 nm, and the second layer has an average thickness of 6 to 9 μm.

[0065] In some embodiments, the second layer has a lower surface roughness than the same device in the absence of the first layer.

[0066] In some embodiments, the second layer is relatively smooth and / or substantially free of cracks.

[0067] In some embodiments, the device includes optical devices, electronic devices, optoelectronic devices, or combinations thereof. In some embodiments, the device includes lateral devices, vertical devices, or combinations thereof.

[0068] This specification also discloses methods for manufacturing any of the devices disclosed herein. For example, a method may include depositing a first layer on a substrate and depositing a second layer on the first layer. In some embodiments, the first and / or second layer is deposited using metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), hydride gas-phase epitaxy (HVPE), pulsed laser deposition (PLD), low-pressure chemical vapor deposition (LPCVD), mist CVD, or a combination thereof. In some embodiments, the first and / or second layer is deposited using metal-organic chemical vapor deposition (MOCVD).

[0069] In some embodiments, the first layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof. In some embodiments, the aluminum concentration in the first layer can be controlled by controlling the concentration and / or ratio of the precursors, temperature, pressure, or a combination thereof.

[0070] In some embodiments, the method involves pouring the first layer at a rate of 100 nanometers per hour (nm / hour) or more (for example, 125 nm / hour or more, 150 nm / hour or more, 175 nm / hour or more, 200 nm / hour or more, 225 nm / hour or more, 250 nm / hour or more, 275 nm / hour or more, 300 nm / hour or more, 325 nm / hour or more, 350 nm / hour or more, 375 nm / hour or more, 400 nm / hour or more, 425 nm / hour or more, 450 nm / hour or more, 475 nm / hour or more, 500 nm / hour or more, 525 nm / hour or more, 550 nm / hour or more, 575 nm / hour or more, 600 nm / hour or more, 625 nm / hour or more, 650 nm / hour or more, 675 nm / hour or more, 700 nm / hour or more, 72 It is produced at a growth rate of 5 nm / hour or more, 750 nm / hour or more, 775 nm / hour or more, 800 nm / hour or more, 825 nm / hour or more, 850 nm / hour or more, 875 nm / hour or more, 900 nm / hour or more, 925 nm / hour or more, 950 nm / hour or more, 975 nm / hour or more, 1000 nm / hour or more, 1050 nm / hour or more, 1100 nm / hour or more, 1150 nm / hour or more, 1200 nm / hour or more, 1250 nm / hour or more, 1300 nm / hour or more, 1350 nm / hour or more, 1400 nm / hour or more, 1450 nm / hour or more, 1500 nm / hour or more, 1600 nm / hour or more, 1700 nm / hour or more, 1800 nm / hour or more, or 1900 nm / hour or more.In some embodiments, this method has been used to make the first layer 2000 nm / hour or less (for example, 1900 nm / hour or less, 1800 nm / hour or less, 1700 nm / hour or less, 1600 nm / hour or less, 1500 nm / hour or less, 1450 nm / hour or less, 1400 nm / hour or less, 1350 nm / hour or less, 1300 nm / hour or less, 1250 nm / hour or less, 1200 nm / hour or less, 1150 nm / hour or less, 1100 nm / hour or less, 1050 nm / hour or less, 1000 nm / hour or less, 975 nm / hour or less, 950 nm / hour or less, 925 nm / hour or less, 900 nm / hour or less, 875 nm / hour or less, 850 nm / hour or less, 825 nm / hour or less, 800 nm / hour or less, 7 The first layer is generated at a growth rate of 75 nm / hour or less, 750 nm / hour or less, 725 nm / hour or less, 700 nm / hour or less, 675 nm / hour or less, 650 nm / hour or less, 625 nm / hour or less, 600 nm / hour or less, 575 nm / hour or less, 550 nm / hour or less, 525 nm / hour or less, 500 nm / hour or less, 475 nm / hour or less, 450 nm / hour or less, 425 nm / hour or less, 400 nm / hour or less, 375 nm / hour or less, 350 nm / hour or less, 325 nm / hour or less, 300 nm / hour or less, 275 nm / hour or less, 250 nm / hour or less, 225 nm / hour or less, 200 nm / hour or less, 175 nm / hour or less, 150 nm / hour or less, or 125 nm / hour or less. The growth rate of the first layer may be in the range from any of the minimum values ​​to any of the maximum values ​​above.For example, this method involves applying a first layer at 100-2000 nm / hour (for example, 100-1000 nm / hour, 1000-2000 nm / hour, 100-450 nm / hour, 450-800 nm / hour, 800-1400 nm / hour, 1400-2000 nm / hour, 100-300 nm / hour, 300-500 nm / hour, 500-800 nm / hour, 800-1000 nm / hour) hour, 1000~1200nm / hour, 1200~1400nm / hour, 1400~1600nm / hour, 1600~1800nm / hour, 1800~2000nm / hour, 100~18 00nm / hr, 100~1600nm / hr, 100~1400nm / hr, 100~1200nm / hr, 100~800nm / hr, 100~700nm / hr, 100~600nm / hour, 100~500nm / hour, 100~400nm / hour, 100~200nm / hour, 200~2000nm / hour, 300~2000nm / hour, 400~2000nm / hour, 500~2000nm / hr, 600~2000nm / hr, 700~2000nm / hr, 800~2000nm / hr, 1200~2000nm / hr, 1400~2000nm / hr The first layer can be produced at growth rates of 1600-2000 nm / hour, 200-1800 nm / hour, 300-1600 nm / hour, 200-800 nm / hour, 300-800 nm / hour, 400-800 nm / hour, 600-800 nm / hour, 700-800 nm / hour, 150-750 nm / hour, 200-600 nm / hour, or 350-450 nm / hour. In some embodiments, the method can produce the first layer at a growth rate of 100-800 nm / hour. In some embodiments, the method can produce the first layer at a growth rate of 400 nm / hour.

[0071] In some embodiments, the second layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof. In some embodiments, the second layer is deposited using MOCVD with a Ga-containing precursor and an oxygen-containing precursor.

[0072] In some embodiments, this method involves layering the second layer at a rate of 1 μm / hour or more (for example, 1.5 μm / hour or more, 2 μm / hour or more, 2.5 μm / hour or more, 3 μm / hour or more, 3.5 μm / hour or more, 4 μm / hour or more, 4.5 μm / hour or more, 5 μm / hour or more, 5.5 μm / hour or more, 6 μm / hour or more, 6.5 μm / hour or more, 7 μm / hour or more, 7.5 μm / hour or more, 8 μm / hour or more, 8.5 μm / hour or more, 9 μm / hour or more, 9.5 μm / hour or more, 10 μm / hour or more, 10 It can be produced at growth rates of 0.5 μm / hour or more, 11 μm / hour or more, 11.5 μm / hour or more, 12 μm / hour or more, 12.5 μm / hour or more, 13 μm / hour or more, 13.5 μm / hour or more, 14 μm / hour or more, 14.5 μm / hour or more, 15 μm / hour or more, 15.5 μm / hour or more, 16 μm / hour or more, 16.5 μm / hour or more, 17 μm / hour or more, 17.5 μm / hour or more, 18 μm / hour or more, 18.5 μm / hour or more, or 19 μm / hour or more. In some embodiments, this method allows the second layer to be made at a rate of 20 μm / hour or less (for example, 19.5 μm / hour or less, 19 μm / hour or less, 18.5 μm / hour or less, 18 μm / hour or less, 17.5 μm / hour or less, 17 μm / hour or less, 16.5 μm / hour or less, 16 μm / hour or less, 15.5 μm / hour or less, 15 μm / hour or less, 14.5 μm / hour or less, 14 μm / hour or less, 13.5 μm / hour or less, 13 μm / hour or less, 12.5 μm / hour or less, 12 μm / hour or less, 11.5 μm / hour or less). It can be produced at growth rates of m / hour or less, 11 μm / hour or less, 10.5 μm / hour or less, 10 μm / hour or less, 9.5 μm / hour or less, 9 μm / hour or less, 8.5 μm / hour or less, 8 μm / hour or less, 7.5 μm / hour or less, 7 μm / hour or less, 6.5 μm / hour or less, 6 μm / hour or less, 5.5 μm / hour or less, 5 μm / hour or less, 4.5 μm / hour or less, 4 μm / hour or less, 3.5 μm / hour or less, 3 μm / hour or less, 2.5 μm / hour or less, or 2 μm / hour or less. The growth rate of the second layer may be in the range from any of the minimum values ​​to any of the maximum values ​​above.For example, this method applies a second layer of 1-20 μm / hour (e.g., 1-10 μm / hour, 10-20 μm / hour, 1-5 μm / hour, 5-10 μm / hour, 10-15 μm / hour, 15-20 μm / hour, 1-4 μm / hour, 4-7 μm / hour, 7-10 μm / hour, 10-13 μm / hour, 13-16 μm / hour, 16-20 μm / hour, 1-18 μm / hour, 1-16 μm / hour, 1-14 μm / hour, 1-12 μm / hour, 1-9 μm / hour, 1-8 μm / hour, 1-7 μm / hour, 1-6 μm / hour, 1-3 μm / hour, 2-20 μm / hour, 3-20 μm It can be produced at growth rates of 1-10 μm / hour, 4-20 μm / hour, 5-20 μm / hour, 6-20 μm / hour, 7-20 μm / hour, 8-20 μm / hour, 9-20 μm / hour, 12-20 μm / hour, 14-20 μm / hour, 16-20 μm / hour, 18-20 μm / hour, 2-18 μm / hour, 3-17 μm / hour, 5-15 μm / hour, 2-10 μm / hour, 3-10 μm / hour, 4-10 μm / hour, 6-10 μm / hour, 8-10 μm / hour, 1.5-9.5 μm / hour, 2-6 μm / hour, 2-4 μm / hour, or 2.5-3.5 μm / hour. In some embodiments, this method can produce a second layer at a growth rate of 1-10 μm / hour. In some embodiments, this method can generate a second layer at a growth rate of 3 μm / hour.

[0073] In some embodiments, the Al-containing precursor, the Ga-containing precursor, and / or the oxygen-containing precursor independently contain a fluid such as a gas.

[0074] In some embodiments, the Al-containing precursor includes trimethylaluminum (TMAl), triethylaluminum (TEAl), or a combination thereof. In some embodiments, the Al-containing precursor includes trimethylaluminum (TMAl).

[0075] In some embodiments, the Ga-containing precursor includes trimethylgallium (TMGa), triethylgallium (TEGa), or a combination thereof.

[0076] In some embodiments, the oxygen-containing precursor contains O2.

[0077] In some embodiments, the method further comprises introducing an additional precursor containing a dopant, thereby the first layer and / or second layer further containing the dopant. In some embodiments, the additional precursor is provided as a fluid such as a gas. In some embodiments, the additional precursor contains an n-type dopant such as a silicon-containing precursor.

[0078] In some embodiments, a carrier gas is supplied independently to an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, an additional precursor (if any), or a combination thereof. In some embodiments, the carrier gas includes argon, helium, N2, or a combination thereof.

[0079] In some embodiments, the method is carried out at a temperature of 650°C or higher (for example, 675°C or higher, 700°C or higher, 725°C or higher, 750°C or higher, 775°C or higher, 800°C or higher, 825°C or higher, 850°C or higher, 875°C or higher, 900°C or higher, 925°C or higher, 950°C or higher, 975°C or higher, 1000°C or higher, 1025°C or higher, 1050°C or higher, or 1075°C or higher). In some embodiments, the temperature is 1100°C or less (e.g., 1075°C or less, 1050°C or less, 1025°C or less, 1000°C or less, 975°C or less, 950°C or less, 925°C or less, 900°C or less, 875°C or less, 850°C or less, 825°C or less, 800°C or less, 775°C or less, 750°C or less, 725°C or less, 700°C or less, or 675°C or less). The temperature may range from any of the minimum values ​​above to any of the maximum values ​​above. For example, the temperature range is 650℃~1100℃ (for example, 650℃~875℃, 875℃~1100℃, 650℃~750℃, 750℃~850℃, 850℃~950℃, 950℃~1100℃, 650℃~1000℃, 650℃~900℃, 650℃~825℃, 650℃~800℃, 750℃~1100℃, 850℃~1100℃, 900℃~1100℃, 675℃~1075℃, 700℃~1000℃, 750℃~1000℃, 825℃~1000℃, 850℃~1000℃, 900℃~1000℃, 950℃~1000℃, 675℃~975℃, Alternatively, the temperature may be between 700°C and 950°C. In some examples, the temperature may be between 650°C and 1000°C.

[0080] In some embodiments, the method is carried out at a pressure of 5 Tors or more (for example, 10 Tors or more, 15 Tors or more, 20 Tors or more, 25 Tors or more, 30 Tors or more, 35 Tors or more, 40 Tors or more, 45 Tors or more, 50 Tors or more, 60 Tors or more, 70 Tors or more, 80 Tors or more, 90 Tors or more, 100 Tors or more, 125 Tors or more, 150 Tors or more, 175 Tors or more, 200 Tors or more, 225 Tors or more, 250 Tors or more, 300 Tors or more, 350 Tors or more, 400 Tors or more, 450 Tors or more, 500 Tors or more, or 550 Tors or more). In some embodiments, the pressure is 600 Torr or less (e.g., 550 Torr or less, 500 Torr or less, 450 Torr or less, 400 Torr or less, 350 Torr or less, 300 Torr or less, 250 Torr or less, 225 Torr or less, 200 Torr or less, 175 Torr or less, 150 Torr or less, 125 Torr or less, 100 Torr or less, 90 Torr or less, 80 Torr or less, 70 Torr or less, 60 Torr or less, 50 Torr or less, 45 Torr or less, 40 Torr or less, 35 Torr or less, 30 Torr or less, 25 Torr or less, 20 Torr or less, 15 Torr or less, or 10 Torr or less). The pressure may range from any of the minimum values ​​above to any of the maximum values ​​above. For example, the pressure could be between 5 and 600 Torr (e.g., 5 to 300 Torr, 300 to 600 Torr, 5 to 200 Torr, 200 to 400 Torr, 400 to 600 Torr, 5 to 500 Torr, 5 to 400 Torr, 5 to 100 Torr, 5 to 50 Torr, 5 to 25 Torr, 25 to 600 Torr, 50 to 600 Torr, 100 to 600 Torr, 200 to 600 Torr, 500 to 600 Torr, 10 to 550 Torr, or 25 to 500 Torr).

[0081] In some embodiments, the method is carried out at a temperature of 650 to 1000°C and / or a pressure of 5 to 600 Torr.

[0082] Numerous embodiments of the present invention have been described. Needless to say, it is understood that various modifications can be made without departing from the spirit and scope of the invention. Therefore, other embodiments are within the scope of the following claims.

[0083] The following examples are intended to further illustrate specific embodiments of the devices and methods described herein and are not intended to limit the scope of the claims. [Examples]

[0084] The following examples are provided below to illustrate the methods and results according to the subject matter disclosed herein. These examples are not intended to include all aspects of the subject matter disclosed herein, but rather to illustrate representative methods and results. These examples are not intended to exclude equivalents and variations of the invention that would be apparent to those skilled in the art.

[0085] While we strive to ensure accuracy in numerical values ​​(e.g., quantity, temperature, etc.), please allow for a certain degree of error and deviation. Unless otherwise specified, parts refer to parts by weight, temperature to °C or ambient temperature, and pressure to atmospheric pressure or near atmospheric pressure. There are many variations and combinations of measurement conditions, such as component concentration, temperature, pressure, and other measurement ranges and conditions that can be used to optimize the described process.

[0086] Example 1 - (Al x Ga 1-x (001) A method for deploying a thick β-Ga2O3 film on a Ga2O3 substrate using a 2O3 buffer layer. β-Ga2O3 is considered a promising semiconductor material for next-generation high-power electronic devices due to its outstanding properties, including a large energy bandgap (4.8 eV), controllable n-type doping, and a high predicted breakdown field strength (8 MV / cm) [1]. Another significant advantage of β-Ga2O3 over other broad-bandgap (GaN, SiC) and ultra-broad-bandgap (diamond, AlN) materials is the availability of high-quality single-crystal native substrates in various orientations, grown using cost-effective and scalable melt growth techniques [2].

[0087] In recent years, significant progress has been demonstrated in the development of β-Ga2O3-based lateral and vertical devices for high-voltage and high-power electronic applications. Recently, lateral β-Ga2O3 Schottky barrier diodes (SBDs) with high dielectric constant (high-k) dielectric superjunction (SJ) structures have demonstrated high breakdown voltages of 1.487 kV and 1.34 GW / cm². 2 The power figure of merit (PFOM) of has been demonstrated [3]. Meanwhile, β-Ga2O3 vertical rectifiers using planar or trench metal oxide semiconductor (MOS) technology have been reported to have breakdown voltages exceeding 2kV and are an attractive approach due to their large current-carrying capacitance in vertical form factor devices [4,5]. A β-Ga2O3 vertical Schottky barrier diode with a stepped field plate on a SiO2-filled deep trench has been shown to have a voltage of 7.6 mΩcm 2 The device was successfully demonstrated with excellent device characteristics, including a low on-resistance and an off-state breakdown voltage of 1.66 kV.[6] A vertical fin structure SBD was used to achieve a breakdown voltage of 2.89 kV and a power output of 0.80 GW / cm². 2 (BV 2 / R on,sp The figure of merit (BFOM) of the ) barrier diode has been achieved [4]. More recently, a vertical β-Ga2O3 Schottky barrier diode utilizing a vertical structure with deep trenches of SiO2 has achieved a record high breakdown voltage of up to 6kV and 3.4mΩcm 2 The low on-resistance provides edge termination, with a capacity of 7.4-10.6 GW / cm². 2 It has been reported that this results in a record-breaking power figure of merit for variga in the range of [7]. Because β-Ga2O3 does not have a shallow p-type dopant, the integration of n-type Ga2O3 and p-type NiO in vertical PN heterojunction power diodes results in lower leakage current and on-resistance than conventional planar rectifiers [8,9]. For example, the β-Ga2O3 / NiO heterojunction PN diode has a record-high breakdown voltage of 8.32kV and an on-resistance of 5.24mΩcm 2 Ratio on-resistance: 13.2 GW / cm² 2 The power performance figure and turn-on voltage of 1.8V have been demonstrated.[9] β- Ga2O3 / NiO heterozygous 接合The power figure of merit of PN diodes has already exceeded the 1-D unipolar limit of GaN and SiC [9], demonstrating the immense potential of vertical devices for higher voltage applications of β-Ga2O3-based power electronics.

[0088] To develop high-power electronic devices with even higher reverse breakdown voltages, a thick drift layer with a smooth surface morphology and controllable low doping is required. Therefore, growth of high-quality, thick β-Ga2O3 at a relatively fast growth rate is necessary. Relatively fast growth rates of epitaxial β-Ga2O3 layers on (010)-oriented β-Ga2O3 substrates have been demonstrated using various methods such as low-pressure chemical vapor deposition (LPCVD)

[10] and metal-organic chemical vapor deposition (MOCVD)

[11] , but thick film growth often results in the formation of three-dimensional (3D) island-like structures on the growth surface, which is undesirable for device fabrication. Previous studies on MOCVD homoepitaxial growth of (100)β-Ga2O3 on axial β-Ga2O3 substrates have revealed stacking faults and twin lamellar formation in epitaxial films

[12] . By introducing an appropriate miscut angle to the substrate, step-flow growth of β-Ga2O3 thin films on the (100) plane is possible, but the growth rate on this plane was found to be considerably slower than the growth rate on the (010) plane

[13] , suggesting a challenge in developing a thick β-Ga2O3 drift layer on a (100) oriented β-Ga2O3 substrate.

[0089] (001)-oriented β-Ga2O3 substrates are primarily used for the homoepitaxial growth of β-Ga2O3 films at high growth rates (>10 μm / hour) via halide vapor phase epitaxy (HVPE)

[14] . The majority of reported vertical β-Ga2O3 devices, such as Schottky barrier diodes, pn heterojunctions, or metal-insulator-semiconductor (MIS) diodes, are fabricated on (001)-oriented β-Ga2O3 films. However, HVPE growth at high growth rates tends to result in significant surface roughness, including surface steps and depressions [15,16], requiring chemical mechanical polishing (CMP) processes for device fabrication. The CMP process can lead to impurity incorporation and also limits the possibility of developing heterostructures in situ.

[0090] Recently, we demonstrated MOCVD growth of high-quality β-Ga2O3 thin films on a (001) orientation axis β-Ga2O3 substrate at a growth rate of 3 μm / hour using trimethylgallium (TMGa) as the Ga precursor. The surface morphology is very smooth across the entire sample, which is significantly different from when a (010)β-Ga2O3 substrate is used

[11] . However, one different problem arises with MOCVD growth of β-Ga2O3 on a (001)Ga2O3 substrate: the epitaxial film forms cracking across the surface. This problem becomes more severe as the film thickness increases. Figures 1A–1D show typical surface morphology of an MOCVD-grown (001)β-Ga2O3 film. The surface remains very smooth between the cracking lines. In this particular example, the (001) epitaxial layer was grown at a growth rate of 3 μm / hour to a film thickness of 9 μm. Therefore, it is important to address the problem of surface cracking of the β-Ga2O3 epitaxy on (001)Ga2O3 substrates. Addressing this problem is highly promising for paving new avenues for realizing high-performance vertical power devices based on ultra-wide bandgap β-Ga2O3 materials.

[0091] In this specification, as shown in Figure 2, thin β-(Al x Ga 1-xTechniques for depositing thick β-Ga2O3 films on (001)Ga2O3 substrates by inserting a (001)Al2O3 buffer layer are described. The Al composition can be varied between, for example, 0% and 50%, and the buffer layer thickness can be varied between a few nanometers and several hundred nanometers. The AlGaO buffer layer can suppress cracking of the top β-Ga2O3 epitaxial layer, especially when the Ga2O3 layer is grown at a relatively thick thickness and a relatively fast growth rate.

[0092] In an example of MOCVD growth of (001)β-Ga2O3 on top of a (001)Ga2O3 substrate, the effect of different Al compositions in the β-(Al x Ga 1-x )2O3 buffer layer was investigated. The thickness of the β-(Al x Ga 1-x )2O3 buffer layer was about 20 nm. A schematic cross-sectional view is shown in FIG. 3. For MOCVD growth of the thin β-(Al x Ga 1-x )2O3 buffer layer, triethylgallium (TEGa), trimethylaluminum (TMAl), and pure O2 were used as Ga, Al, and O precursors, respectively. Argon (Ar) was used as the carrier gas. Phase-pure β-(Al x Ga 1-x )2O3 thin films with various Al compositions can be achieved by systematically adjusting the VI / III molar ratio, temperature, and chamber pressure. For growth of the top β-Ga2O3 layer, TMGa was utilized as the Ga precursor and Ar was used as the carrier gas. Typical growth temperatures are in the range of 650 to 1000 °C, and typical chamber pressures vary from 5 to 600 Torr. Silicon donors can be used as effective n-type dopants in MOCVD-grown β-Ga2O3 and β-(Al x Ga 1-x )2O3 films.

[0093] In this example, the thin β-(Al x Ga 1-x) The 2O3 buffer layer (20 nm) was grown at a low growth rate (400 nm / h) prior to the growth of a thick β-Ga2O3 layer (6 μm) at a high growth rate (3 μm / h). Figures 4A to 4E show low-amplitude optical macroscopic surface images of β-Ga2O3 films grown using TMGa on a (001) β-Ga2O3 substrate with thin β-(Al x Ga 1-x )2O3 buffer layers with different Al compositions. As the Al composition increases from 0% to 29%, the crack density decreases. Note that for the sample with a 29% β-(Al × Ga 1-x )2O3 buffer layer, there are only two cracks in the 5×5 mm 2 β-Ga2O3 epi-film, indicating a significant improvement.

[0094] A similar trend was observed for β-Ga2O3 films (about 9 μm) grown with TMGa on a (001) β-Ga2O3 substrate with a thin β-(Al x Ga 1-x )2O3 layer. As shown in Figures 5A to 5B, the surface of the 9-μm β-Ga2O3 film with a 29% β-(Al x Ga 1-x )2O3 buffer layer shows a much lower crack density compared to that without a buffer layer.

[0095] For device applications, the thickness and Al composition of the β-(Al × Ga 1-x )2O3 buffer layer can be optimized with respect to the growth rate and total layer thickness of the target β-Ga2O3 film.

[0096] References 1. A.J. Green et al. APL Mater. 10, 029201 (2022). 2. A. Kuramata et al. Jpn. J. Appl. Phys. 55, 1202A2 (2016). 3. S. Roy et al. IEEE Electron Device Lett. 43(12), 2037 (2022). 4. W. Li et al., IEEE Electron Device Lett. 41, 107 (2020). 5. J. Yang et al., ECS J. Solid State Sci. Technol. 7, Q92 (2018). 6. S. Kumar et al., Appl. Phys. Express 15, 054001 (2022). 7. P. Dong et al., IEEE Electron Device Lett. 43(5), 765 (2022). 8. J.-S. Li et al., Appl. Phys. Lett. 121, 042105 (2022). 9. J. Zhang et al., Nat. Commun. 13, 3900 (2022). 10. Y. Zhang et al., J. Vac. Sci. Technol. A 38, 050806 (2020). 11. L. Meng et al., Cryst. Growth Des. 22, 3896 (2022). 12. R. Schewski et al., J. Appl. Phys. 120, 225308 (2016). 13. S. Bin Anooz et al., Appl. Phys. Lett. 116, 182106 (2020). 14. Z. Hu et al., IEEE Electron Device Lett. 39, 1564 (2018). 15. H. Murakami et al., Appl. Phys. Express �, 015503 (2014). 16. J.H. Leach et al., APL Mater. 7, 022504 (2019).

[0097] Example 2 Figure 6 shows a schematic diagram of a 6 μm thick film of (001)Ga2O3 grown on an AlGaO buffer layer on a (001)GaO substrate.

[0098] Optical images of the Ga2O3 film are shown in Figures 7 and 8. Only two cracks were observed in the sample (indicated by arrows in Figure 8), and they were concentrated on one side.

[0099] SEM images of the Ga2O3 film are shown in Figures 9 and 10.

[0100] The surface was further analyzed using AFM (Figure 11).

[0101] Exemplary aspects Taking into consideration the compositions, devices, systems, and methods described herein, specific embodiments of the invention described in more detail are described below. However, the specific embodiments described herein should not be construed as having any limiting effect on any different claims, including different or more general teachings set forth herein, nor should the “specific” embodiments be construed as being somewhat limited in any way other than the literal meaning of the words and phrases used herein.

[0102] Example 1: (001)Ga2O3 substrate and (Al x Ga 1-x A first layer containing )2O3 (where x is 0 to 0.5), and (Al z Ga 1-z A device comprising a first layer and a second layer comprising 2O3 (where z is 0 to 0.2), wherein the first layer is disposed on the substrate and the second layer is disposed on the first layer, thereby sandwiching the first layer between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 1000 μm.

[0103] Example 2: The device according to any embodiment of this specification, particularly Example 1, wherein the substrate includes a (001)β-Ga2O3 substrate.

[0104] Example 3: The first layer is (Alx Ga 1-x A device according to any of the embodiments of this specification, particularly the device described in Example 1 or Example 2, comprising 2O3 (where x is between 0 and 0.3).

[0105] Example 4: A device according to any example of this specification, particularly Examples 1 to 3, wherein the first layer has an average thickness of 5 to 1000 nm, 5 nm to 500 nm, 10 nm to 100 nm, or 15 to 25 nm.

[0106] Example 5: The device according to any example of this specification, particularly Examples 1 to 4, wherein the second layer comprises Ga2O3.

[0107] Example 6: The device according to any example of this specification, particularly Examples 1 to 5, wherein the second layer comprises β-Ga2O3.

[0108] Example 7: The device according to any example of this specification, particularly Examples 1 to 6, wherein the second layer has an average thickness of 5 to 100 μm.

[0109] Example 8: The device according to any example of this specification, particularly Examples 1 to 7, wherein the second layer has an average thickness of 5 to 15 μm.

[0110] Example 9: The device according to any example of this specification, particularly Examples 1 to 8, wherein the second layer has an average thickness of 6 to 9 μm.

[0111] Example 10: The device comprises a (001)Ga2O3 substrate and (Al x Ga 1-x A device according to any embodiment of this specification, particularly any of Examples 1 to 9, comprising a first layer containing )2O3 (where x is 0 to 0.5) and a second layer containing Ga2O3, wherein the first layer is disposed on the substrate and the second layer is disposed on the first layer, so that the first layer is sandwiched between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 15 μm.

[0112] Example 11: The device according to any embodiment of this specification, in particular any of Examples 1 to 10, wherein the second layer has a lower surface roughness than the surface roughness of the same device in the absence of the first layer.

[0113] Example 12: The device according to any embodiment of this specification, particularly Examples 1 to 11, wherein the second layer is relatively smooth and / or substantially free of cracks.

[0114] Example 13: Any embodiment of this specification, particularly the devices described in Examples 1 to 12, wherein the device includes an optical device, an electronic device, an optoelectronic device, or a combination thereof.

[0115] Example 14: Any embodiment of this specification, particularly the devices described in Examples 1 to 13, wherein the device includes a horizontal device, a vertical device, or a combination thereof.

[0116] Example 15: A method for manufacturing a device according to any embodiment of this specification, particularly Examples 1 to 14, comprising depositing the first layer on the substrate and depositing the second layer on the first layer.

[0117] Example 16: Any example of this specification, particularly the method of Example 15, wherein the first layer and / or the second layer are deposited using metal-organic chemical vapor deposition (MOCVD).

[0118] Example 17: The method according to any of the embodiments herein, particularly the method according to Example 15 or Example 16, wherein the first layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof.

[0119] Example 18: The method according to any of the examples herein, particularly the method according to Examples 15-17, wherein the first layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, and an oxygen-containing precursor.

[0120] Example 19: The method according to any of the embodiments herein, particularly Example 17 or Example 18, wherein the concentration of aluminum in the first layer can be controlled by controlling the concentration and / or ratio of the precursor, temperature, pressure, or a combination thereof.

[0121] Example 20: The method according to any of the embodiments herein, particularly the method according to Examples 15-19, wherein the method generates the first layer at a growth rate of 100-2000 nm / hour.

[0122] Example 21: A device according to any example of this specification, particularly Examples 15-20, wherein the method generates the first layer at a growth rate of 100-800 nm / hour, for example, 400 nm / hour.

[0123] Example 22: The method according to any of the embodiments herein, particularly those according to Examples 15-21, wherein the second layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof.

[0124] Example 23: The device according to any example herein, particularly Examples 15-22, wherein the second layer is deposited using MOCVD with a Ga-containing precursor and an oxygen-containing precursor.

[0125] Example 24: The method according to any of the embodiments herein, particularly those according to Examples 15-23, wherein the method generates the second layer at a growth rate of 1-20 μm / hour.

[0126] Example 25: The device according to any example of this specification, particularly Examples 15-24, wherein the method generates the second layer at a growth rate of 1-10 μm / hour, for example, 3 μm / hour.

[0127] Example 26: The method according to any of the embodiments herein, particularly those according to Examples 17 to 25, wherein the Al-containing precursor, the Ga-containing precursor, and / or the oxygen-containing precursor independently contain a fluid such as a gas.

[0128] Example 27: The method according to any of the examples herein, particularly those according to Examples 17-26, wherein the Al-containing precursor comprises trimethylaluminum (TMAl), triethylaluminum (TEAl), or a combination thereof.

[0129] Example 28: The method according to any of the examples herein, particularly those of Examples 17 to 27, wherein the Al-containing precursor comprises trimethylaluminum (TMAl).

[0130] Example 29: The method according to any of the examples herein, particularly those according to Examples 17-28, wherein the Ga-containing precursor comprises trimethylgallium (TMGa), triethylgallium (TEGa), or a combination thereof.

[0131] Example 30: The method according to any of the examples specified herein, particularly those of Examples 17 to 29, wherein the oxygen-containing precursor contains O2.

[0132] Example 31: The method according to any of the embodiments herein, particularly the method according to Examples 17-30, further comprising introducing an additional precursor containing a dopant, thereby the first layer and / or the second layer further containing the dopant.

[0133] Example 32: The method according to any embodiment of this specification, in particular Example 31, wherein the additional precursor is provided as a fluid such as a gas.

[0134] Example 33: The method according to any example of this specification, particularly Example 31 or Example 32, wherein the additional precursor comprises an n-type dopant such as a silicon-containing precursor.

[0135] Example 34: Any example of this specification, particularly the method of Examples 17 to 33, wherein a carrier gas is supplied independently to the Al-containing precursor, the Ga-containing precursor, the oxygen-containing precursor, the additional precursor (if present), or a combination thereof.

[0136] Example 35: Any example of this specification, particularly the method of Example 34, wherein the carrier gas includes argon, helium, N2, or a combination thereof.

[0137] Example 36: The method according to any of the embodiments of this specification, particularly the methods of Examples 15 to 35, wherein the method is carried out at a temperature of 650 to 1100°C and / or at a pressure of 5 to 600 Torr.

[0138] Example 37: The method according to any of the embodiments of this specification, particularly the methods of Examples 15 to 36, wherein the method is carried out at a temperature of 650 to 1000°C and / or at a pressure of 5 to 600 Torr.

[0139] Other obvious and unique advantages of the present invention will be apparent to those skilled in the art. It will be understood that certain properties and partial combinations are beneficial and can be used regardless of other properties and partial combinations. It will be understood that all matters in this specification described or shown in the accompanying drawings should be interpreted as illustrative rather than restrictive, since many possible embodiments of the present invention contemplated and within the scope of the claims can be carried out without departing from that scope.

[0140] The methods of the appended claims are not limited by the specific methods described herein, which are intended to be illustrative of some aspects of the claims, and any functionally equivalent methods are intended to be included in the claims. In addition to those shown and described herein, various variations of the methods are intended to be included in the appended claims. Furthermore, although only certain representative method steps disclosed herein are specifically described, other combinations of method steps are also intended to be included in the appended claims, even if not specifically enumerated. Thus, combinations of steps, elements, components, or constituents may be explicitly mentioned herein, but other combinations of steps, elements, components, and constituents are included even if not explicitly mentioned.

Claims

1. (001) Ga ２ O ３ substrate, and a first layer containing (Al ｘ Ga １－ｘ ) ２ O ３ (where x is 0 to 0.5), and a second layer containing (Al ｚ Ga １－ｚ ) ２ O ３ (where z is 0 to 0.2), the device comprising: the first layer being disposed on the substrate, the second layer being disposed on the first layer, whereby the first layer is sandwiched between the substrate and the second layer, and the second layer having an average thickness of 5 μm to 1000 μm, said device.

2. The aforementioned substrate is (001)β-Ga ２ O ３ The device according to claim 1, including a substrate.

3. The first layer is (Al ｘ Ga １－ｘ ) ２ O ３ The device according to claim 1 or claim 2, comprising (where x is between 0 and 0.3).

4. The device according to any one of claims 1 to 3, wherein the first layer has an average thickness of 5 to 1000 nm, 5 nm to 500 nm, 10 nm to 100 nm, or 15 to 25 nm.

5. The second layer is Ga ２ O ３ A device according to any one of claims 1 to 4, including the device described in any one of claims 1 to 4.

6. The second layer is β-Ga ２ O ３ A device according to any one of claims 1 to 5, including the device described in any one of claims 1 to 5.

7. The device according to any one of claims 1 to 6, wherein the second layer has an average thickness of 5 to 100 μm.

8. The device according to any one of claims 1 to 7, wherein the second layer has an average thickness of 5 to 15 μm.

9. The device according to any one of claims 1 to 8, wherein the second layer has an average thickness of 6 to 9 μm.

10. The device is (001) Ga ２ O ３ The substrate and (Al ｘ Ga １－ｘ ) ２ O ３ A first layer containing (where x is between 0 and 0.5), and Ga ２ O ３ The device according to any one of claims 1 to 9, comprising a second layer including the first layer disposed on the substrate, the second layer disposed on the first layer, so that the first layer is sandwiched between the substrate and the second layer, and the second layer has an average thickness of 5 μm to 15 μm.

11. The device according to any one of claims 1 to 10, wherein the second layer has a lower surface roughness than the surface roughness of the same device in the absence of the first layer.

12. The device according to any one of claims 1 to 11, wherein the second layer is relatively smooth and / or substantially free of cracks.

13. The device according to any one of claims 1 to 12, wherein the device includes an optical device, an electronic device, an optoelectronic device, or a combination thereof.

14. The device according to any one of claims 1 to 13, wherein the device includes a horizontal device, a vertical device, or a combination thereof.

15. A method for manufacturing the device according to any one of claims 1 to 14, comprising depositing the first layer on the substrate and depositing the second layer on the first layer.

16. The method according to claim 15, wherein the first layer and / or the second layer are deposited using metal-organic chemical vapor deposition (MOCVD).

17. The method according to claim 15 or 16, wherein the first layer is deposited using MOCVD using an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof.

18. The method according to any one of claims 15 to 17, wherein the first layer is deposited using MOCVD with an Al-containing precursor, a Ga-containing precursor, and an oxygen-containing precursor.

19. The method according to claim 17 or 18, wherein the concentration of aluminum in the first layer can be controlled by controlling the concentration and / or ratio of the precursor, temperature, pressure, or a combination thereof.

20. The method according to any one of claims 15 to 19, wherein the method generates the first layer at a growth rate of 100 to 2000 nm / hour.

21. The device according to any one of claims 15 to 20, wherein the method generates the first layer at a growth rate of 100 to 800 nm / hour, for example, 400 nm / hour.

22. The method according to any one of claims 15 to 21, wherein the second layer is deposited using MOCVD using an Al-containing precursor, a Ga-containing precursor, an oxygen-containing precursor, or a combination thereof.

23. The device according to any one of claims 15 to 22, wherein the second layer is deposited using MOCVD with a Ga-containing precursor and an oxygen-containing precursor.

24. The method according to any one of claims 15 to 23, wherein the method generates the second layer at a growth rate of 1 to 20 μm / hour.

25. The device according to any one of claims 15 to 24, wherein the method generates the second layer at a growth rate of 1 to 10 μm / hour, for example, 3 μm / hour.

26. The method according to any one of claims 17 to 25, wherein the Al-containing precursor, the Ga-containing precursor, and / or the oxygen-containing precursor independently contain a fluid such as a gas.

27. The method according to any one of claims 17 to 26, wherein the Al-containing precursor comprises trimethylaluminum (TMAl), triethylaluminum (TEAl), or a combination thereof.

28. The method according to any one of claims 17 to 27, wherein the Al-containing precursor comprises trimethylaluminum (TMAl).

29. The method according to any one of claims 17 to 28, wherein the Ga-containing precursor comprises trimethylgallium (TMGa), triethylgallium (TEGa), or a combination thereof.

30. The oxygen-containing precursor is O ２ The method according to any one of claims 17 to 29, including the method described in any one of claims 17 to 29.

31. The method according to any one of claims 17 to 30, further comprising introducing an additional precursor comprising a dopant, thereby the first layer and / or the second layer further comprising the dopant.

32. The method according to claim 31, wherein the additional precursor is provided as a fluid such as a gas.

33. The method according to claim 31 or claim 32, wherein the additional precursor comprises an n-type dopant such as a silicon-containing precursor.

34. The method according to any one of claims 17 to 33, wherein a carrier gas is supplied independently to the Al-containing precursor, the Ga-containing precursor, the oxygen-containing precursor, the additional precursor (if any), or a combination thereof.

35. The carrier gas is argon, helium, N ２ The method according to claim 34, including, or a combination thereof.

36. The method according to any one of claims 15 to 35, wherein the method is carried out at a temperature of 650 to 1100°C and / or at a pressure of 5 to 600 Torr.

37. The method according to any one of claims 15 to 36, wherein the method is carried out at a temperature of 650 to 1000°C and / or at a pressure of 5 to 600 Torr.

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